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v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * TI TRF7970a RFID/NFC Transceiver Driver
   4 *
   5 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
   6 *
   7 * Author: Erick Macias <emacias@ti.com>
   8 * Author: Felipe Balbi <balbi@ti.com>
   9 * Author: Mark A. Greer <mgreer@animalcreek.com>
 
 
 
 
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/device.h>
  14#include <linux/netdevice.h>
  15#include <linux/interrupt.h>
  16#include <linux/pm_runtime.h>
  17#include <linux/nfc.h>
  18#include <linux/skbuff.h>
  19#include <linux/delay.h>
  20#include <linux/gpio/consumer.h>
  21#include <linux/of.h>
 
  22#include <linux/spi/spi.h>
  23#include <linux/regulator/consumer.h>
  24
  25#include <net/nfc/nfc.h>
  26#include <net/nfc/digital.h>
  27
  28/* There are 3 ways the host can communicate with the trf7970a:
  29 * parallel mode, SPI with Slave Select (SS) mode, and SPI without
  30 * SS mode.  The driver only supports the two SPI modes.
  31 *
  32 * The trf7970a is very timing sensitive and the VIN, EN2, and EN
  33 * pins must asserted in that order and with specific delays in between.
  34 * The delays used in the driver were provided by TI and have been
  35 * confirmed to work with this driver.  There is a bug with the current
  36 * version of the trf7970a that requires that EN2 remain low no matter
  37 * what.  If it goes high, it will generate an RF field even when in
  38 * passive target mode.  TI has indicated that the chip will work okay
  39 * when EN2 is left low.  The 'en2-rf-quirk' device tree property
  40 * indicates that trf7970a currently being used has the erratum and
  41 * that EN2 must be kept low.
  42 *
  43 * Timeouts are implemented using the delayed workqueue kernel facility.
  44 * Timeouts are required so things don't hang when there is no response
  45 * from the trf7970a (or tag).  Using this mechanism creates a race with
  46 * interrupts, however.  That is, an interrupt and a timeout could occur
  47 * closely enough together that one is blocked by the mutex while the other
  48 * executes.  When the timeout handler executes first and blocks the
  49 * interrupt handler, it will eventually set the state to IDLE so the
  50 * interrupt handler will check the state and exit with no harm done.
  51 * When the interrupt handler executes first and blocks the timeout handler,
  52 * the cancel_delayed_work() call will know that it didn't cancel the
  53 * work item (i.e., timeout) and will return zero.  That return code is
  54 * used by the timer handler to indicate that it should ignore the timeout
  55 * once its unblocked.
  56 *
  57 * Aborting an active command isn't as simple as it seems because the only
  58 * way to abort a command that's already been sent to the tag is so turn
  59 * off power to the tag.  If we do that, though, we'd have to go through
  60 * the entire anticollision procedure again but the digital layer doesn't
  61 * support that.  So, if an abort is received before trf7970a_send_cmd()
  62 * has sent the command to the tag, it simply returns -ECANCELED.  If the
  63 * command has already been sent to the tag, then the driver continues
  64 * normally and recieves the response data (or error) but just before
  65 * sending the data upstream, it frees the rx_skb and sends -ECANCELED
  66 * upstream instead.  If the command failed, that error will be sent
  67 * upstream.
  68 *
  69 * When recieving data from a tag and the interrupt status register has
  70 * only the SRX bit set, it means that all of the data has been received
  71 * (once what's in the fifo has been read).  However, depending on timing
  72 * an interrupt status with only the SRX bit set may not be recived.  In
  73 * those cases, the timeout mechanism is used to wait 20 ms in case more
  74 * data arrives.  After 20 ms, it is assumed that all of the data has been
  75 * received and the accumulated rx data is sent upstream.  The
  76 * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
  77 * (i.e., it indicates that some data has been received but we're not sure
  78 * if there is more coming so a timeout in this state means all data has
  79 * been received and there isn't an error).  The delay is 20 ms since delays
  80 * of ~16 ms have been observed during testing.
  81 *
  82 * When transmitting a frame larger than the FIFO size (127 bytes), the
  83 * driver will wait 20 ms for the FIFO to drain past the low-watermark
  84 * and generate an interrupt.  The low-watermark set to 32 bytes so the
  85 * interrupt should fire after 127 - 32 = 95 bytes have been sent.  At
  86 * the lowest possible bit rate (6.62 kbps for 15693), it will take up
  87 * to ~14.35 ms so 20 ms is used for the timeout.
  88 *
  89 * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
  90 * Having only 4 bits in the FIFO won't normally generate an interrupt so
  91 * driver enables the '4_bit_RX' bit of the Special Functions register 1
  92 * to cause an interrupt in that case.  Leaving that bit for a read command
  93 * messes up the data returned so it is only enabled when the framing is
  94 * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
  95 * Unfortunately, that means that the driver has to peek into tx frames
  96 * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'.  This is done by
  97 * the trf7970a_per_cmd_config() routine.
  98 *
  99 * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
 100 * frequencies and whether to use low or high data rates in the flags byte
 101 * of the frame.  This means that the driver has to peek at all 15693 frames
 102 * to determine what speed to set the communication to.  In addition, write
 103 * and lock commands use the OPTION flag to indicate that an EOF must be
 104 * sent to the tag before it will send its response.  So the driver has to
 105 * examine all frames for that reason too.
 106 *
 107 * It is unclear how long to wait before sending the EOF.  According to the
 108 * Note under Table 1-1 in section 1.6 of
 109 * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
 110 * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
 111 * enough so 20 ms is used.  So the timer is set to 40 ms - 20 ms to drain
 112 * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
 113 * ensure the wait is long enough before sending the EOF.  This seems to work
 114 * reliably.
 115 */
 116
 117#define TRF7970A_SUPPORTED_PROTOCOLS \
 118		(NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |	\
 119		 NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
 120		 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
 121
 122#define TRF7970A_AUTOSUSPEND_DELAY		30000	/* 30 seconds */
 123#define TRF7970A_13MHZ_CLOCK_FREQUENCY		13560000
 124#define TRF7970A_27MHZ_CLOCK_FREQUENCY		27120000
 125
 126#define TRF7970A_RX_SKB_ALLOC_SIZE		256
 127
 128#define TRF7970A_FIFO_SIZE			127
 129
 130/* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
 131#define TRF7970A_TX_MAX				(4096 - 1)
 132
 133#define TRF7970A_WAIT_FOR_TX_IRQ		20
 134#define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT	20
 135#define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT	20
 136#define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF	40
 137
 138/* Guard times for various RF technologies (in us) */
 139#define TRF7970A_GUARD_TIME_NFCA		5000
 140#define TRF7970A_GUARD_TIME_NFCB		5000
 141#define TRF7970A_GUARD_TIME_NFCF		20000
 142#define TRF7970A_GUARD_TIME_15693		1000
 143
 144/* Quirks */
 145/* Erratum: When reading IRQ Status register on trf7970a, we must issue a
 146 * read continuous command for IRQ Status and Collision Position registers.
 147 */
 148#define TRF7970A_QUIRK_IRQ_STATUS_READ		BIT(0)
 149#define TRF7970A_QUIRK_EN2_MUST_STAY_LOW	BIT(1)
 
 150
 151/* Direct commands */
 152#define TRF7970A_CMD_IDLE			0x00
 153#define TRF7970A_CMD_SOFT_INIT			0x03
 154#define TRF7970A_CMD_RF_COLLISION		0x04
 155#define TRF7970A_CMD_RF_COLLISION_RESPONSE_N	0x05
 156#define TRF7970A_CMD_RF_COLLISION_RESPONSE_0	0x06
 157#define TRF7970A_CMD_FIFO_RESET			0x0f
 158#define TRF7970A_CMD_TRANSMIT_NO_CRC		0x10
 159#define TRF7970A_CMD_TRANSMIT			0x11
 160#define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC	0x12
 161#define TRF7970A_CMD_DELAY_TRANSMIT		0x13
 162#define TRF7970A_CMD_EOF			0x14
 163#define TRF7970A_CMD_CLOSE_SLOT			0x15
 164#define TRF7970A_CMD_BLOCK_RX			0x16
 165#define TRF7970A_CMD_ENABLE_RX			0x17
 166#define TRF7970A_CMD_TEST_INT_RF		0x18
 167#define TRF7970A_CMD_TEST_EXT_RF		0x19
 168#define TRF7970A_CMD_RX_GAIN_ADJUST		0x1a
 169
 170/* Bits determining whether its a direct command or register R/W,
 171 * whether to use a continuous SPI transaction or not, and the actual
 172 * direct cmd opcode or register address.
 173 */
 174#define TRF7970A_CMD_BIT_CTRL			BIT(7)
 175#define TRF7970A_CMD_BIT_RW			BIT(6)
 176#define TRF7970A_CMD_BIT_CONTINUOUS		BIT(5)
 177#define TRF7970A_CMD_BIT_OPCODE(opcode)		((opcode) & 0x1f)
 178
 179/* Registers addresses */
 180#define TRF7970A_CHIP_STATUS_CTRL		0x00
 181#define TRF7970A_ISO_CTRL			0x01
 182#define TRF7970A_ISO14443B_TX_OPTIONS		0x02
 183#define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS	0x03
 184#define TRF7970A_TX_TIMER_SETTING_H_BYTE	0x04
 185#define TRF7970A_TX_TIMER_SETTING_L_BYTE	0x05
 186#define TRF7970A_TX_PULSE_LENGTH_CTRL		0x06
 187#define TRF7970A_RX_NO_RESPONSE_WAIT		0x07
 188#define TRF7970A_RX_WAIT_TIME			0x08
 189#define TRF7970A_MODULATOR_SYS_CLK_CTRL		0x09
 190#define TRF7970A_RX_SPECIAL_SETTINGS		0x0a
 191#define TRF7970A_REG_IO_CTRL			0x0b
 192#define TRF7970A_IRQ_STATUS			0x0c
 193#define TRF7970A_COLLISION_IRQ_MASK		0x0d
 194#define TRF7970A_COLLISION_POSITION		0x0e
 195#define TRF7970A_RSSI_OSC_STATUS		0x0f
 196#define TRF7970A_SPECIAL_FCN_REG1		0x10
 197#define TRF7970A_SPECIAL_FCN_REG2		0x11
 198#define TRF7970A_RAM1				0x12
 199#define TRF7970A_RAM2				0x13
 200#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS	0x14
 201#define TRF7970A_NFC_LOW_FIELD_LEVEL		0x16
 202#define TRF7970A_NFCID1				0x17
 203#define TRF7970A_NFC_TARGET_LEVEL		0x18
 204#define TRF79070A_NFC_TARGET_PROTOCOL		0x19
 205#define TRF7970A_TEST_REGISTER1			0x1a
 206#define TRF7970A_TEST_REGISTER2			0x1b
 207#define TRF7970A_FIFO_STATUS			0x1c
 208#define TRF7970A_TX_LENGTH_BYTE1		0x1d
 209#define TRF7970A_TX_LENGTH_BYTE2		0x1e
 210#define TRF7970A_FIFO_IO_REGISTER		0x1f
 211
 212/* Chip Status Control Register Bits */
 213#define TRF7970A_CHIP_STATUS_VRS5_3		BIT(0)
 214#define TRF7970A_CHIP_STATUS_REC_ON		BIT(1)
 215#define TRF7970A_CHIP_STATUS_AGC_ON		BIT(2)
 216#define TRF7970A_CHIP_STATUS_PM_ON		BIT(3)
 217#define TRF7970A_CHIP_STATUS_RF_PWR		BIT(4)
 218#define TRF7970A_CHIP_STATUS_RF_ON		BIT(5)
 219#define TRF7970A_CHIP_STATUS_DIRECT		BIT(6)
 220#define TRF7970A_CHIP_STATUS_STBY		BIT(7)
 221
 222/* ISO Control Register Bits */
 223#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662	0x00
 224#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662	0x01
 225#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648	0x02
 226#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648	0x03
 227#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a	0x04
 228#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667	0x05
 229#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669	0x06
 230#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669	0x07
 231#define TRF7970A_ISO_CTRL_14443A_106		0x08
 232#define TRF7970A_ISO_CTRL_14443A_212		0x09
 233#define TRF7970A_ISO_CTRL_14443A_424		0x0a
 234#define TRF7970A_ISO_CTRL_14443A_848		0x0b
 235#define TRF7970A_ISO_CTRL_14443B_106		0x0c
 236#define TRF7970A_ISO_CTRL_14443B_212		0x0d
 237#define TRF7970A_ISO_CTRL_14443B_424		0x0e
 238#define TRF7970A_ISO_CTRL_14443B_848		0x0f
 239#define TRF7970A_ISO_CTRL_FELICA_212		0x1a
 240#define TRF7970A_ISO_CTRL_FELICA_424		0x1b
 241#define TRF7970A_ISO_CTRL_NFC_NFCA_106		0x01
 242#define TRF7970A_ISO_CTRL_NFC_NFCF_212		0x02
 243#define TRF7970A_ISO_CTRL_NFC_NFCF_424		0x03
 244#define TRF7970A_ISO_CTRL_NFC_CE_14443A		0x00
 245#define TRF7970A_ISO_CTRL_NFC_CE_14443B		0x01
 246#define TRF7970A_ISO_CTRL_NFC_CE		BIT(2)
 247#define TRF7970A_ISO_CTRL_NFC_ACTIVE		BIT(3)
 248#define TRF7970A_ISO_CTRL_NFC_INITIATOR		BIT(4)
 249#define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE	BIT(5)
 250#define TRF7970A_ISO_CTRL_RFID			BIT(5)
 251#define TRF7970A_ISO_CTRL_DIR_MODE		BIT(6)
 252#define TRF7970A_ISO_CTRL_RX_CRC_N		BIT(7)	/* true == No CRC */
 253
 254#define TRF7970A_ISO_CTRL_RFID_SPEED_MASK	0x1f
 255
 256/* Modulator and SYS_CLK Control Register Bits */
 257#define TRF7970A_MODULATOR_DEPTH(n)		((n) & 0x7)
 258#define TRF7970A_MODULATOR_DEPTH_ASK10		(TRF7970A_MODULATOR_DEPTH(0))
 259#define TRF7970A_MODULATOR_DEPTH_OOK		(TRF7970A_MODULATOR_DEPTH(1))
 260#define TRF7970A_MODULATOR_DEPTH_ASK7		(TRF7970A_MODULATOR_DEPTH(2))
 261#define TRF7970A_MODULATOR_DEPTH_ASK8_5		(TRF7970A_MODULATOR_DEPTH(3))
 262#define TRF7970A_MODULATOR_DEPTH_ASK13		(TRF7970A_MODULATOR_DEPTH(4))
 263#define TRF7970A_MODULATOR_DEPTH_ASK16		(TRF7970A_MODULATOR_DEPTH(5))
 264#define TRF7970A_MODULATOR_DEPTH_ASK22		(TRF7970A_MODULATOR_DEPTH(6))
 265#define TRF7970A_MODULATOR_DEPTH_ASK30		(TRF7970A_MODULATOR_DEPTH(7))
 266#define TRF7970A_MODULATOR_EN_ANA		BIT(3)
 267#define TRF7970A_MODULATOR_CLK(n)		(((n) & 0x3) << 4)
 268#define TRF7970A_MODULATOR_CLK_DISABLED		(TRF7970A_MODULATOR_CLK(0))
 269#define TRF7970A_MODULATOR_CLK_3_6		(TRF7970A_MODULATOR_CLK(1))
 270#define TRF7970A_MODULATOR_CLK_6_13		(TRF7970A_MODULATOR_CLK(2))
 271#define TRF7970A_MODULATOR_CLK_13_27		(TRF7970A_MODULATOR_CLK(3))
 272#define TRF7970A_MODULATOR_EN_OOK		BIT(6)
 273#define TRF7970A_MODULATOR_27MHZ		BIT(7)
 274
 275#define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM	BIT(0)
 276#define TRF7970A_RX_SPECIAL_SETTINGS_AGCR	BIT(1)
 277#define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB	(0x0 << 2)
 278#define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB	(0x1 << 2)
 279#define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB	(0x2 << 2)
 280#define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB	(0x3 << 2)
 281#define TRF7970A_RX_SPECIAL_SETTINGS_HBT	BIT(4)
 282#define TRF7970A_RX_SPECIAL_SETTINGS_M848	BIT(5)
 283#define TRF7970A_RX_SPECIAL_SETTINGS_C424	BIT(6)
 284#define TRF7970A_RX_SPECIAL_SETTINGS_C212	BIT(7)
 285
 286#define TRF7970A_REG_IO_CTRL_VRS(v)		((v) & 0x07)
 287#define TRF7970A_REG_IO_CTRL_IO_LOW		BIT(5)
 288#define TRF7970A_REG_IO_CTRL_EN_EXT_PA		BIT(6)
 289#define TRF7970A_REG_IO_CTRL_AUTO_REG		BIT(7)
 290
 291/* IRQ Status Register Bits */
 292#define TRF7970A_IRQ_STATUS_NORESP		BIT(0)	/* ISO15693 only */
 293#define TRF7970A_IRQ_STATUS_NFC_COL_ERROR	BIT(0)
 294#define TRF7970A_IRQ_STATUS_COL			BIT(1)
 295#define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR	BIT(2)
 296#define TRF7970A_IRQ_STATUS_NFC_RF		BIT(2)
 297#define TRF7970A_IRQ_STATUS_PARITY_ERROR	BIT(3)
 298#define TRF7970A_IRQ_STATUS_NFC_SDD		BIT(3)
 299#define TRF7970A_IRQ_STATUS_CRC_ERROR		BIT(4)
 300#define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR	BIT(4)
 301#define TRF7970A_IRQ_STATUS_FIFO		BIT(5)
 302#define TRF7970A_IRQ_STATUS_SRX			BIT(6)
 303#define TRF7970A_IRQ_STATUS_TX			BIT(7)
 304
 305#define TRF7970A_IRQ_STATUS_ERROR				\
 306		(TRF7970A_IRQ_STATUS_COL |			\
 307		 TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR |	\
 308		 TRF7970A_IRQ_STATUS_PARITY_ERROR |		\
 309		 TRF7970A_IRQ_STATUS_CRC_ERROR)
 310
 311#define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK	(BIT(2) | BIT(1) | BIT(0))
 312#define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK	(BIT(5) | BIT(4) | BIT(3))
 313#define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK	BIT(6)
 314
 315#define TRF7970A_SPECIAL_FCN_REG1_COL_7_6		BIT(0)
 316#define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL		BIT(1)
 317#define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX		BIT(2)
 318#define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE		BIT(3)
 319#define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US	BIT(4)
 320#define TRF7970A_SPECIAL_FCN_REG1_PAR43			BIT(5)
 321
 322#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124	(0x0 << 2)
 323#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120	(0x1 << 2)
 324#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112	(0x2 << 2)
 325#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96	(0x3 << 2)
 326#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4	0x0
 327#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8	0x1
 328#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16	0x2
 329#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32	0x3
 330
 331#define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v)	((v) & 0x07)
 332#define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS	BIT(7)
 333
 334#define TRF7970A_NFC_TARGET_LEVEL_RFDET(v)	((v) & 0x07)
 335#define TRF7970A_NFC_TARGET_LEVEL_HI_RF		BIT(3)
 336#define TRF7970A_NFC_TARGET_LEVEL_SDD_EN	BIT(5)
 337#define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES	(0x0 << 6)
 338#define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES	(0x1 << 6)
 339#define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES	(0x2 << 6)
 340
 341#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106		BIT(0)
 342#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212		BIT(1)
 343#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424		(BIT(0) | BIT(1))
 344#define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B	BIT(2)
 345#define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106		BIT(3)
 346#define TRF79070A_NFC_TARGET_PROTOCOL_FELICA		BIT(4)
 347#define TRF79070A_NFC_TARGET_PROTOCOL_RF_L		BIT(6)
 348#define TRF79070A_NFC_TARGET_PROTOCOL_RF_H		BIT(7)
 349
 350#define TRF79070A_NFC_TARGET_PROTOCOL_106A		\
 351	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 352	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 353	  TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 |	\
 354	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 355
 356#define TRF79070A_NFC_TARGET_PROTOCOL_106B		\
 357	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 358	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 359	  TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B |	\
 360	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 361
 362#define TRF79070A_NFC_TARGET_PROTOCOL_212F		\
 363	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 364	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 365	  TRF79070A_NFC_TARGET_PROTOCOL_FELICA |	\
 366	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
 367
 368#define TRF79070A_NFC_TARGET_PROTOCOL_424F		\
 369	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 370	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 371	  TRF79070A_NFC_TARGET_PROTOCOL_FELICA |	\
 372	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424)
 373
 374#define TRF7970A_FIFO_STATUS_OVERFLOW		BIT(7)
 375
 376/* NFC (ISO/IEC 14443A) Type 2 Tag commands */
 377#define NFC_T2T_CMD_READ			0x30
 378
 379/* ISO 15693 commands codes */
 380#define ISO15693_CMD_INVENTORY			0x01
 381#define ISO15693_CMD_READ_SINGLE_BLOCK		0x20
 382#define ISO15693_CMD_WRITE_SINGLE_BLOCK		0x21
 383#define ISO15693_CMD_LOCK_BLOCK			0x22
 384#define ISO15693_CMD_READ_MULTIPLE_BLOCK	0x23
 385#define ISO15693_CMD_WRITE_MULTIPLE_BLOCK	0x24
 386#define ISO15693_CMD_SELECT			0x25
 387#define ISO15693_CMD_RESET_TO_READY		0x26
 388#define ISO15693_CMD_WRITE_AFI			0x27
 389#define ISO15693_CMD_LOCK_AFI			0x28
 390#define ISO15693_CMD_WRITE_DSFID		0x29
 391#define ISO15693_CMD_LOCK_DSFID			0x2a
 392#define ISO15693_CMD_GET_SYSTEM_INFO		0x2b
 393#define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS	0x2c
 394
 395/* ISO 15693 request and response flags */
 396#define ISO15693_REQ_FLAG_SUB_CARRIER		BIT(0)
 397#define ISO15693_REQ_FLAG_DATA_RATE		BIT(1)
 398#define ISO15693_REQ_FLAG_INVENTORY		BIT(2)
 399#define ISO15693_REQ_FLAG_PROTOCOL_EXT		BIT(3)
 400#define ISO15693_REQ_FLAG_SELECT		BIT(4)
 401#define ISO15693_REQ_FLAG_AFI			BIT(4)
 402#define ISO15693_REQ_FLAG_ADDRESS		BIT(5)
 403#define ISO15693_REQ_FLAG_NB_SLOTS		BIT(5)
 404#define ISO15693_REQ_FLAG_OPTION		BIT(6)
 405
 406#define ISO15693_REQ_FLAG_SPEED_MASK \
 407		(ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
 408
 409enum trf7970a_state {
 410	TRF7970A_ST_PWR_OFF,
 411	TRF7970A_ST_RF_OFF,
 412	TRF7970A_ST_IDLE,
 413	TRF7970A_ST_IDLE_RX_BLOCKED,
 414	TRF7970A_ST_WAIT_FOR_TX_FIFO,
 415	TRF7970A_ST_WAIT_FOR_RX_DATA,
 416	TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
 417	TRF7970A_ST_WAIT_TO_ISSUE_EOF,
 418	TRF7970A_ST_LISTENING,
 419	TRF7970A_ST_LISTENING_MD,
 420	TRF7970A_ST_MAX
 421};
 422
 423struct trf7970a {
 424	enum trf7970a_state		state;
 425	struct device			*dev;
 426	struct spi_device		*spi;
 427	struct regulator		*regulator;
 428	struct nfc_digital_dev		*ddev;
 429	u32				quirks;
 430	bool				is_initiator;
 431	bool				aborting;
 432	struct sk_buff			*tx_skb;
 433	struct sk_buff			*rx_skb;
 434	nfc_digital_cmd_complete_t	cb;
 435	void				*cb_arg;
 436	u8				chip_status_ctrl;
 437	u8				iso_ctrl;
 438	u8				iso_ctrl_tech;
 439	u8				modulator_sys_clk_ctrl;
 440	u8				special_fcn_reg1;
 441	u8				io_ctrl;
 442	unsigned int			guard_time;
 443	int				technology;
 444	int				framing;
 445	u8				md_rf_tech;
 446	u8				tx_cmd;
 447	bool				issue_eof;
 448	struct gpio_desc		*en_gpiod;
 449	struct gpio_desc		*en2_gpiod;
 
 450	struct mutex			lock;
 451	unsigned int			timeout;
 452	bool				ignore_timeout;
 453	struct delayed_work		timeout_work;
 454};
 455
 
 456static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
 457{
 458	u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
 459	int ret;
 460
 461	dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
 462
 463	ret = spi_write(trf->spi, &cmd, 1);
 464	if (ret)
 465		dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
 466			ret);
 467	return ret;
 468}
 469
 470static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
 471{
 472	u8 addr = TRF7970A_CMD_BIT_RW | reg;
 473	int ret;
 474
 475	ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
 476	if (ret)
 477		dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 478			ret);
 479
 480	dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
 481
 482	return ret;
 483}
 484
 485static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf,
 486			      size_t len)
 487{
 488	u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
 489	struct spi_transfer t[2];
 490	struct spi_message m;
 491	int ret;
 492
 493	dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
 494
 495	spi_message_init(&m);
 496
 497	memset(&t, 0, sizeof(t));
 498
 499	t[0].tx_buf = &addr;
 500	t[0].len = sizeof(addr);
 501	spi_message_add_tail(&t[0], &m);
 502
 503	t[1].rx_buf = buf;
 504	t[1].len = len;
 505	spi_message_add_tail(&t[1], &m);
 506
 507	ret = spi_sync(trf->spi, &m);
 508	if (ret)
 509		dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 510			ret);
 511	return ret;
 512}
 513
 514static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
 515{
 516	u8 buf[2] = { reg, val };
 517	int ret;
 518
 519	dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
 520
 521	ret = spi_write(trf->spi, buf, 2);
 522	if (ret)
 523		dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
 524			buf[0], buf[1], ret);
 525
 526	return ret;
 527}
 528
 529static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
 530{
 531	int ret;
 532	u8 buf[2];
 533	u8 addr;
 534
 535	addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
 536
 537	if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
 538		addr |= TRF7970A_CMD_BIT_CONTINUOUS;
 539		ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 540	} else {
 541		ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
 542	}
 543
 544	if (ret)
 545		dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
 546			__func__, ret);
 547	else
 548		*status = buf[0];
 549
 550	return ret;
 551}
 552
 553static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
 554{
 555	int ret;
 556	u8 buf[2];
 557	u8 addr;
 558
 559	addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
 560	       TRF7970A_CMD_BIT_CONTINUOUS;
 561
 562	ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 563	if (ret)
 564		dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
 565			__func__, ret);
 566	else
 567		*target_proto = buf[0];
 568
 569	return ret;
 570}
 571
 572static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
 573{
 574	int ret;
 575	u8 target_proto, tech;
 576
 577	ret = trf7970a_read_target_proto(trf, &target_proto);
 578	if (ret)
 579		return ret;
 580
 581	switch (target_proto) {
 582	case TRF79070A_NFC_TARGET_PROTOCOL_106A:
 583		tech = NFC_DIGITAL_RF_TECH_106A;
 584		break;
 585	case TRF79070A_NFC_TARGET_PROTOCOL_106B:
 586		tech = NFC_DIGITAL_RF_TECH_106B;
 587		break;
 588	case TRF79070A_NFC_TARGET_PROTOCOL_212F:
 589		tech = NFC_DIGITAL_RF_TECH_212F;
 590		break;
 591	case TRF79070A_NFC_TARGET_PROTOCOL_424F:
 592		tech = NFC_DIGITAL_RF_TECH_424F;
 593		break;
 594	default:
 595		dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
 596			__func__, target_proto);
 597		return -EIO;
 598	}
 599
 600	*rf_tech = tech;
 601
 602	return ret;
 603}
 604
 605static void trf7970a_send_upstream(struct trf7970a *trf)
 606{
 607	dev_kfree_skb_any(trf->tx_skb);
 608	trf->tx_skb = NULL;
 609
 610	if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
 611		print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
 612				     16, 1, trf->rx_skb->data, trf->rx_skb->len,
 613				     false);
 614
 615	trf->state = TRF7970A_ST_IDLE;
 616
 617	if (trf->aborting) {
 618		dev_dbg(trf->dev, "Abort process complete\n");
 619
 620		if (!IS_ERR(trf->rx_skb)) {
 621			kfree_skb(trf->rx_skb);
 622			trf->rx_skb = ERR_PTR(-ECANCELED);
 623		}
 624
 625		trf->aborting = false;
 626	}
 627
 
 
 
 
 
 
 
 628	trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
 629
 630	trf->rx_skb = NULL;
 631}
 632
 633static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
 634{
 635	dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
 636
 637	cancel_delayed_work(&trf->timeout_work);
 638
 639	kfree_skb(trf->rx_skb);
 640	trf->rx_skb = ERR_PTR(errno);
 641
 642	trf7970a_send_upstream(trf);
 643}
 644
 645static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
 646			     unsigned int len, const u8 *prefix,
 647			     unsigned int prefix_len)
 648{
 649	struct spi_transfer t[2];
 650	struct spi_message m;
 651	unsigned int timeout;
 652	int ret;
 653
 654	print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
 655			     16, 1, skb->data, len, false);
 656
 657	spi_message_init(&m);
 658
 659	memset(&t, 0, sizeof(t));
 660
 661	t[0].tx_buf = prefix;
 662	t[0].len = prefix_len;
 663	spi_message_add_tail(&t[0], &m);
 664
 665	t[1].tx_buf = skb->data;
 666	t[1].len = len;
 667	spi_message_add_tail(&t[1], &m);
 668
 669	ret = spi_sync(trf->spi, &m);
 670	if (ret) {
 671		dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
 672			ret);
 673		return ret;
 674	}
 675
 676	skb_pull(skb, len);
 677
 678	if (skb->len > 0) {
 679		trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
 680		timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
 681	} else {
 682		if (trf->issue_eof) {
 683			trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
 684			timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
 685		} else {
 686			trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
 687
 688			if (!trf->timeout)
 689				timeout = TRF7970A_WAIT_FOR_TX_IRQ;
 690			else
 691				timeout = trf->timeout;
 692		}
 693	}
 694
 695	dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
 696		trf->state);
 697
 698	schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
 699
 700	return 0;
 701}
 702
 703static void trf7970a_fill_fifo(struct trf7970a *trf)
 704{
 705	struct sk_buff *skb = trf->tx_skb;
 706	unsigned int len;
 707	int ret;
 708	u8 fifo_bytes;
 709	u8 prefix;
 710
 711	ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 712	if (ret) {
 713		trf7970a_send_err_upstream(trf, ret);
 714		return;
 715	}
 716
 717	dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 718
 719	fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 720
 721	/* Calculate how much more data can be written to the fifo */
 722	len = TRF7970A_FIFO_SIZE - fifo_bytes;
 723	if (!len) {
 724		schedule_delayed_work(&trf->timeout_work,
 725			msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
 726		return;
 727	}
 728
 729	len = min(skb->len, len);
 730
 731	prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
 732
 733	ret = trf7970a_transmit(trf, skb, len, &prefix, sizeof(prefix));
 734	if (ret)
 735		trf7970a_send_err_upstream(trf, ret);
 736}
 737
 738static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
 739{
 740	struct sk_buff *skb = trf->rx_skb;
 741	int ret;
 742	u8 fifo_bytes;
 743
 744	if (status & TRF7970A_IRQ_STATUS_ERROR) {
 745		trf7970a_send_err_upstream(trf, -EIO);
 746		return;
 747	}
 748
 749	ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 750	if (ret) {
 751		trf7970a_send_err_upstream(trf, ret);
 752		return;
 753	}
 754
 755	dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 756
 757	fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 758
 759	if (!fifo_bytes)
 760		goto no_rx_data;
 761
 762	if (fifo_bytes > skb_tailroom(skb)) {
 763		skb = skb_copy_expand(skb, skb_headroom(skb),
 764				      max_t(int, fifo_bytes,
 765					    TRF7970A_RX_SKB_ALLOC_SIZE),
 766				      GFP_KERNEL);
 767		if (!skb) {
 768			trf7970a_send_err_upstream(trf, -ENOMEM);
 769			return;
 770		}
 771
 772		kfree_skb(trf->rx_skb);
 773		trf->rx_skb = skb;
 774	}
 775
 776	ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
 777				 skb_put(skb, fifo_bytes), fifo_bytes);
 778	if (ret) {
 779		trf7970a_send_err_upstream(trf, ret);
 780		return;
 781	}
 782
 783	/* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
 784	if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
 785	    (trf->special_fcn_reg1 == TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
 
 786		skb->data[0] >>= 4;
 787		status = TRF7970A_IRQ_STATUS_SRX;
 788	} else {
 789		trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
 790
 791		ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 792		if (ret) {
 793			trf7970a_send_err_upstream(trf, ret);
 794			return;
 795		}
 796
 797		fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 798
 799		/* If there are bytes in the FIFO, set status to '0' so
 800		 * the if stmt below doesn't fire and the driver will wait
 801		 * for the trf7970a to generate another RX interrupt.
 802		 */
 803		if (fifo_bytes)
 804			status = 0;
 805	}
 806
 807no_rx_data:
 808	if (status == TRF7970A_IRQ_STATUS_SRX) {	/* Receive complete */
 809		trf7970a_send_upstream(trf);
 810		return;
 811	}
 812
 813	dev_dbg(trf->dev, "Setting timeout for %d ms\n",
 814		TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
 815
 816	schedule_delayed_work(&trf->timeout_work,
 817			   msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
 818}
 819
 820static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 821{
 822	struct trf7970a *trf = dev_id;
 823	int ret;
 824	u8 status, fifo_bytes, iso_ctrl;
 825
 826	mutex_lock(&trf->lock);
 827
 828	if (trf->state == TRF7970A_ST_RF_OFF) {
 829		mutex_unlock(&trf->lock);
 830		return IRQ_NONE;
 831	}
 832
 833	ret = trf7970a_read_irqstatus(trf, &status);
 834	if (ret) {
 835		mutex_unlock(&trf->lock);
 836		return IRQ_NONE;
 837	}
 838
 839	dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
 840		status);
 841
 842	if (!status) {
 843		mutex_unlock(&trf->lock);
 844		return IRQ_NONE;
 845	}
 846
 847	switch (trf->state) {
 848	case TRF7970A_ST_IDLE:
 849	case TRF7970A_ST_IDLE_RX_BLOCKED:
 850		/* If initiator and getting interrupts caused by RF noise,
 851		 * turn off the receiver to avoid unnecessary interrupts.
 852		 * It will be turned back on in trf7970a_send_cmd() when
 853		 * the next command is issued.
 854		 */
 855		if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
 856			trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
 857			trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
 858		}
 859
 860		trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 861		break;
 862	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
 863		if (status & TRF7970A_IRQ_STATUS_TX) {
 864			trf->ignore_timeout =
 865			    !cancel_delayed_work(&trf->timeout_work);
 866			trf7970a_fill_fifo(trf);
 867		} else {
 868			trf7970a_send_err_upstream(trf, -EIO);
 869		}
 870		break;
 871	case TRF7970A_ST_WAIT_FOR_RX_DATA:
 872	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
 873		if (status & TRF7970A_IRQ_STATUS_SRX) {
 874			trf->ignore_timeout =
 875			    !cancel_delayed_work(&trf->timeout_work);
 876			trf7970a_drain_fifo(trf, status);
 877		} else if (status & TRF7970A_IRQ_STATUS_FIFO) {
 878			ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
 879					    &fifo_bytes);
 880
 881			fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 882
 883			if (ret)
 884				trf7970a_send_err_upstream(trf, ret);
 885			else if (!fifo_bytes)
 886				trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 887		} else if ((status == TRF7970A_IRQ_STATUS_TX) ||
 888			   (!trf->is_initiator &&
 889			    (status == (TRF7970A_IRQ_STATUS_TX |
 890					TRF7970A_IRQ_STATUS_NFC_RF)))) {
 891			trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 892
 893			if (!trf->timeout) {
 894				trf->ignore_timeout =
 895				    !cancel_delayed_work(&trf->timeout_work);
 896				trf->rx_skb = ERR_PTR(0);
 897				trf7970a_send_upstream(trf);
 898				break;
 899			}
 900
 901			if (trf->is_initiator)
 902				break;
 903
 904			iso_ctrl = trf->iso_ctrl;
 905
 906			switch (trf->framing) {
 907			case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
 908				trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
 909				iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
 910				trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 911				break;
 912			case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
 913				trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
 914				iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
 915				trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 916				break;
 917			case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
 918				ret = trf7970a_write(trf,
 919					 TRF7970A_SPECIAL_FCN_REG1,
 920					 TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
 921				if (ret)
 922					goto err_unlock_exit;
 923
 924				trf->special_fcn_reg1 =
 925				    TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
 926				break;
 927			default:
 928				break;
 929			}
 930
 931			if (iso_ctrl != trf->iso_ctrl) {
 932				ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
 933						     iso_ctrl);
 934				if (ret)
 935					goto err_unlock_exit;
 936
 937				trf->iso_ctrl = iso_ctrl;
 938			}
 939		} else {
 940			trf7970a_send_err_upstream(trf, -EIO);
 941		}
 942		break;
 943	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
 944		if (status != TRF7970A_IRQ_STATUS_TX)
 945			trf7970a_send_err_upstream(trf, -EIO);
 946		break;
 947	case TRF7970A_ST_LISTENING:
 948		if (status & TRF7970A_IRQ_STATUS_SRX) {
 949			trf->ignore_timeout =
 950			    !cancel_delayed_work(&trf->timeout_work);
 951			trf7970a_drain_fifo(trf, status);
 952		} else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 953			trf7970a_send_err_upstream(trf, -EIO);
 954		}
 955		break;
 956	case TRF7970A_ST_LISTENING_MD:
 957		if (status & TRF7970A_IRQ_STATUS_SRX) {
 958			trf->ignore_timeout =
 959			    !cancel_delayed_work(&trf->timeout_work);
 960
 961			ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
 962			if (ret) {
 963				trf7970a_send_err_upstream(trf, ret);
 964			} else {
 965				trf->state = TRF7970A_ST_LISTENING;
 966				trf7970a_drain_fifo(trf, status);
 967			}
 968		} else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 969			trf7970a_send_err_upstream(trf, -EIO);
 970		}
 971		break;
 972	default:
 973		dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
 974			__func__, trf->state);
 975	}
 976
 977err_unlock_exit:
 978	mutex_unlock(&trf->lock);
 979	return IRQ_HANDLED;
 980}
 981
 982static void trf7970a_issue_eof(struct trf7970a *trf)
 983{
 984	int ret;
 985
 986	dev_dbg(trf->dev, "Issuing EOF\n");
 987
 988	ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 989	if (ret)
 990		trf7970a_send_err_upstream(trf, ret);
 991
 992	ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
 993	if (ret)
 994		trf7970a_send_err_upstream(trf, ret);
 995
 996	trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
 997
 998	dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
 999		trf->timeout, trf->state);
1000
1001	schedule_delayed_work(&trf->timeout_work,
1002			      msecs_to_jiffies(trf->timeout));
1003}
1004
1005static void trf7970a_timeout_work_handler(struct work_struct *work)
1006{
1007	struct trf7970a *trf = container_of(work, struct trf7970a,
1008					    timeout_work.work);
1009
1010	dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1011		trf->state, trf->ignore_timeout);
1012
1013	mutex_lock(&trf->lock);
1014
1015	if (trf->ignore_timeout)
1016		trf->ignore_timeout = false;
1017	else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1018		trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1019	else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1020		trf7970a_issue_eof(trf);
1021	else
1022		trf7970a_send_err_upstream(trf, -ETIMEDOUT);
1023
1024	mutex_unlock(&trf->lock);
1025}
1026
1027static int trf7970a_init(struct trf7970a *trf)
1028{
1029	int ret;
1030
1031	dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1032
1033	ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1034	if (ret)
1035		goto err_out;
1036
1037	ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1038	if (ret)
1039		goto err_out;
1040
1041	ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1042			     trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1043	if (ret)
1044		goto err_out;
1045
1046	ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1047	if (ret)
1048		goto err_out;
1049
1050	usleep_range(1000, 2000);
1051
1052	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1053
1054	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1055			     trf->modulator_sys_clk_ctrl);
1056	if (ret)
1057		goto err_out;
1058
 
 
1059	ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1060			     TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1061			     TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1062	if (ret)
1063		goto err_out;
1064
1065	ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1066	if (ret)
1067		goto err_out;
1068
1069	trf->special_fcn_reg1 = 0;
1070
1071	trf->iso_ctrl = 0xff;
1072	return 0;
1073
1074err_out:
1075	dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1076	return ret;
1077}
1078
1079static void trf7970a_switch_rf_off(struct trf7970a *trf)
1080{
1081	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1082	    (trf->state == TRF7970A_ST_RF_OFF))
1083		return;
1084
1085	dev_dbg(trf->dev, "Switching rf off\n");
1086
1087	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1088
1089	trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1090
1091	trf->aborting = false;
1092	trf->state = TRF7970A_ST_RF_OFF;
1093
1094	pm_runtime_mark_last_busy(trf->dev);
1095	pm_runtime_put_autosuspend(trf->dev);
1096}
1097
1098static int trf7970a_switch_rf_on(struct trf7970a *trf)
1099{
1100	int ret;
1101
1102	dev_dbg(trf->dev, "Switching rf on\n");
1103
1104	pm_runtime_get_sync(trf->dev);
1105
1106	if (trf->state != TRF7970A_ST_RF_OFF) {	/* Power on, RF off */
1107		dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1108			trf->state);
1109		return -EINVAL;
1110	}
1111
1112	ret = trf7970a_init(trf);
1113	if (ret) {
1114		dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1115		return ret;
1116	}
1117
1118	trf->state = TRF7970A_ST_IDLE;
1119
1120	return 0;
1121}
1122
1123static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1124{
1125	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1126	int ret = 0;
1127
1128	dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1129
1130	mutex_lock(&trf->lock);
1131
1132	if (on) {
1133		switch (trf->state) {
1134		case TRF7970A_ST_PWR_OFF:
1135		case TRF7970A_ST_RF_OFF:
1136			ret = trf7970a_switch_rf_on(trf);
1137			break;
1138		case TRF7970A_ST_IDLE:
1139		case TRF7970A_ST_IDLE_RX_BLOCKED:
1140			break;
1141		default:
1142			dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1143				__func__, trf->state, on);
1144			trf7970a_switch_rf_off(trf);
1145			ret = -EINVAL;
1146		}
1147	} else {
1148		switch (trf->state) {
1149		case TRF7970A_ST_PWR_OFF:
1150		case TRF7970A_ST_RF_OFF:
1151			break;
1152		default:
1153			dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1154				__func__, trf->state, on);
1155			ret = -EINVAL;
1156			fallthrough;
1157		case TRF7970A_ST_IDLE:
1158		case TRF7970A_ST_IDLE_RX_BLOCKED:
1159		case TRF7970A_ST_WAIT_FOR_RX_DATA:
1160		case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1161			trf7970a_switch_rf_off(trf);
1162		}
1163	}
1164
1165	mutex_unlock(&trf->lock);
1166	return ret;
1167}
1168
1169static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1170{
1171	int ret = 0;
1172
1173	dev_dbg(trf->dev, "rf technology: %d\n", tech);
1174
1175	switch (tech) {
1176	case NFC_DIGITAL_RF_TECH_106A:
1177		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1178		trf->modulator_sys_clk_ctrl =
1179		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1180		    TRF7970A_MODULATOR_DEPTH_OOK;
1181		trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1182		break;
1183	case NFC_DIGITAL_RF_TECH_106B:
1184		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1185		trf->modulator_sys_clk_ctrl =
1186		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1187		    TRF7970A_MODULATOR_DEPTH_ASK10;
1188		trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1189		break;
1190	case NFC_DIGITAL_RF_TECH_212F:
1191		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1192		trf->modulator_sys_clk_ctrl =
1193		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1194		    TRF7970A_MODULATOR_DEPTH_ASK10;
1195		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1196		break;
1197	case NFC_DIGITAL_RF_TECH_424F:
1198		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1199		trf->modulator_sys_clk_ctrl =
1200		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1201		    TRF7970A_MODULATOR_DEPTH_ASK10;
1202		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1203		break;
1204	case NFC_DIGITAL_RF_TECH_ISO15693:
1205		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1206		trf->modulator_sys_clk_ctrl =
1207		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1208		    TRF7970A_MODULATOR_DEPTH_OOK;
1209		trf->guard_time = TRF7970A_GUARD_TIME_15693;
1210		break;
1211	default:
1212		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1213		return -EINVAL;
1214	}
1215
1216	trf->technology = tech;
1217
1218	/* If in initiator mode and not changing the RF tech due to a
1219	 * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1220	 * trf7970a_init()), clear the NFC Target Detection Level register
1221	 * due to erratum.
1222	 */
1223	if (trf->iso_ctrl == 0xff)
1224		ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1225
1226	return ret;
1227}
1228
1229static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1230{
1231	int ret;
1232	u8 rssi;
1233
1234	ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1235			     trf->chip_status_ctrl |
1236			     TRF7970A_CHIP_STATUS_REC_ON);
1237	if (ret)
1238		return ret;
1239
1240	ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1241	if (ret)
1242		return ret;
1243
1244	usleep_range(50, 60);
1245
1246	ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1247	if (ret)
1248		return ret;
1249
1250	ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1251			     trf->chip_status_ctrl);
1252	if (ret)
1253		return ret;
1254
1255	if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1256		*is_rf_field = true;
1257	else
1258		*is_rf_field = false;
1259
1260	return 0;
1261}
1262
1263static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1264{
1265	u8 iso_ctrl = trf->iso_ctrl_tech;
1266	bool is_rf_field = false;
1267	int ret;
1268
1269	dev_dbg(trf->dev, "framing: %d\n", framing);
1270
1271	switch (framing) {
1272	case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1273	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1274		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1275		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1276		break;
1277	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1278	case NFC_DIGITAL_FRAMING_NFCA_T4T:
1279	case NFC_DIGITAL_FRAMING_NFCB:
1280	case NFC_DIGITAL_FRAMING_NFCB_T4T:
1281	case NFC_DIGITAL_FRAMING_NFCF:
1282	case NFC_DIGITAL_FRAMING_NFCF_T3T:
1283	case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1284	case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1285	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1286	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1287		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1288		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1289		break;
1290	case NFC_DIGITAL_FRAMING_NFCA_T2T:
1291		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1292		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1293		break;
1294	default:
1295		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1296		return -EINVAL;
1297	}
1298
1299	trf->framing = framing;
1300
1301	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1302		ret = trf7970a_is_rf_field(trf, &is_rf_field);
1303		if (ret)
1304			return ret;
1305
1306		if (is_rf_field)
1307			return -EBUSY;
1308	}
1309
1310	if (iso_ctrl != trf->iso_ctrl) {
1311		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1312		if (ret)
1313			return ret;
1314
1315		trf->iso_ctrl = iso_ctrl;
1316
1317		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1318				     trf->modulator_sys_clk_ctrl);
1319		if (ret)
1320			return ret;
1321	}
1322
1323	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1324		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1325				     trf->chip_status_ctrl |
1326				     TRF7970A_CHIP_STATUS_RF_ON);
1327		if (ret)
1328			return ret;
1329
1330		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1331
1332		usleep_range(trf->guard_time, trf->guard_time + 1000);
1333	}
1334
1335	return 0;
1336}
1337
1338static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1339				    int param)
1340{
1341	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1342	int ret;
1343
1344	dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1345
1346	mutex_lock(&trf->lock);
1347
1348	trf->is_initiator = true;
1349
1350	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1351	    (trf->state == TRF7970A_ST_RF_OFF)) {
1352		ret = trf7970a_switch_rf_on(trf);
1353		if (ret)
1354			goto err_unlock;
1355	}
1356
1357	switch (type) {
1358	case NFC_DIGITAL_CONFIG_RF_TECH:
1359		ret = trf7970a_in_config_rf_tech(trf, param);
1360		break;
1361	case NFC_DIGITAL_CONFIG_FRAMING:
1362		ret = trf7970a_in_config_framing(trf, param);
1363		break;
1364	default:
1365		dev_dbg(trf->dev, "Unknown type: %d\n", type);
1366		ret = -EINVAL;
1367	}
1368
1369err_unlock:
1370	mutex_unlock(&trf->lock);
1371	return ret;
1372}
1373
1374static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1375{
1376	switch (cmd) {
1377	case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1378	case ISO15693_CMD_LOCK_BLOCK:
1379	case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1380	case ISO15693_CMD_WRITE_AFI:
1381	case ISO15693_CMD_LOCK_AFI:
1382	case ISO15693_CMD_WRITE_DSFID:
1383	case ISO15693_CMD_LOCK_DSFID:
1384		return 1;
 
1385	default:
1386		return 0;
1387	}
1388}
1389
1390static int trf7970a_per_cmd_config(struct trf7970a *trf,
1391				   const struct sk_buff *skb)
1392{
1393	const u8 *req = skb->data;
1394	u8 special_fcn_reg1, iso_ctrl;
1395	int ret;
1396
1397	trf->issue_eof = false;
1398
1399	/* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1400	 * special functions register 1 is cleared; otherwise, its a write or
1401	 * sector select command and '4_bit_RX' must be set.
1402	 *
1403	 * When issuing an ISO 15693 command, inspect the flags byte to see
1404	 * what speed to use.  Also, remember if the OPTION flag is set on
1405	 * a Type 5 write or lock command so the driver will know that it
1406	 * has to send an EOF in order to get a response.
1407	 */
1408	if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1409	    (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1410		if (req[0] == NFC_T2T_CMD_READ)
1411			special_fcn_reg1 = 0;
1412		else
1413			special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1414
1415		if (special_fcn_reg1 != trf->special_fcn_reg1) {
1416			ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1417					     special_fcn_reg1);
1418			if (ret)
1419				return ret;
1420
1421			trf->special_fcn_reg1 = special_fcn_reg1;
1422		}
1423	} else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1424		iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1425
1426		switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1427		case 0x00:
1428			iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1429			break;
1430		case ISO15693_REQ_FLAG_SUB_CARRIER:
1431			iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1432			break;
1433		case ISO15693_REQ_FLAG_DATA_RATE:
1434			iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1435			break;
1436		case (ISO15693_REQ_FLAG_SUB_CARRIER |
1437		      ISO15693_REQ_FLAG_DATA_RATE):
1438			iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1439			break;
1440		}
1441
1442		if (iso_ctrl != trf->iso_ctrl) {
1443			ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1444			if (ret)
1445				return ret;
1446
1447			trf->iso_ctrl = iso_ctrl;
1448		}
1449
1450		if ((trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) &&
1451		    trf7970a_is_iso15693_write_or_lock(req[1]) &&
1452		    (req[0] & ISO15693_REQ_FLAG_OPTION))
1453			trf->issue_eof = true;
 
 
 
 
 
1454	}
1455
1456	return 0;
1457}
1458
1459static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1460			     struct sk_buff *skb, u16 timeout,
1461			     nfc_digital_cmd_complete_t cb, void *arg)
1462{
1463	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1464	u8 prefix[5];
1465	unsigned int len;
1466	int ret;
1467	u8 status;
1468
1469	dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1470		trf->state, timeout, skb->len);
1471
1472	if (skb->len > TRF7970A_TX_MAX)
1473		return -EINVAL;
1474
1475	mutex_lock(&trf->lock);
1476
1477	if ((trf->state != TRF7970A_ST_IDLE) &&
1478	    (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1479		dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1480			trf->state);
1481		ret = -EIO;
1482		goto out_err;
1483	}
1484
1485	if (trf->aborting) {
1486		dev_dbg(trf->dev, "Abort process complete\n");
1487		trf->aborting = false;
1488		ret = -ECANCELED;
1489		goto out_err;
1490	}
1491
1492	if (timeout) {
1493		trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1494						 GFP_KERNEL);
1495		if (!trf->rx_skb) {
1496			dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1497			ret = -ENOMEM;
1498			goto out_err;
1499		}
1500	}
1501
1502	if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1503		ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1504		if (ret)
1505			goto out_err;
1506
1507		trf->state = TRF7970A_ST_IDLE;
1508	}
1509
1510	if (trf->is_initiator) {
1511		ret = trf7970a_per_cmd_config(trf, skb);
1512		if (ret)
1513			goto out_err;
1514	}
1515
1516	trf->ddev = ddev;
1517	trf->tx_skb = skb;
1518	trf->cb = cb;
1519	trf->cb_arg = arg;
1520	trf->timeout = timeout;
1521	trf->ignore_timeout = false;
1522
1523	len = skb->len;
1524
1525	/* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1526	 * on what the current framing is, the address of the TX length byte 1
1527	 * register (0x1d), and the 2 byte length of the data to be transmitted.
1528	 * That totals 5 bytes.
1529	 */
1530	prefix[0] = TRF7970A_CMD_BIT_CTRL |
1531	    TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1532	prefix[1] = TRF7970A_CMD_BIT_CTRL |
1533	    TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1534	prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1535
1536	if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1537		prefix[3] = 0x00;
1538		prefix[4] = 0x0f;	/* 7 bits */
1539	} else {
1540		prefix[3] = (len & 0xf00) >> 4;
1541		prefix[3] |= ((len & 0xf0) >> 4);
1542		prefix[4] = ((len & 0x0f) << 4);
1543	}
1544
1545	len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1546
1547	/* Clear possible spurious interrupt */
1548	ret = trf7970a_read_irqstatus(trf, &status);
1549	if (ret)
1550		goto out_err;
1551
1552	ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1553	if (ret) {
1554		kfree_skb(trf->rx_skb);
1555		trf->rx_skb = NULL;
1556	}
1557
1558out_err:
1559	mutex_unlock(&trf->lock);
1560	return ret;
1561}
1562
1563static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1564{
1565	int ret = 0;
1566
1567	dev_dbg(trf->dev, "rf technology: %d\n", tech);
1568
1569	switch (tech) {
1570	case NFC_DIGITAL_RF_TECH_106A:
1571		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1572		    TRF7970A_ISO_CTRL_NFC_CE | TRF7970A_ISO_CTRL_NFC_CE_14443A;
1573		trf->modulator_sys_clk_ctrl =
1574		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1575		    TRF7970A_MODULATOR_DEPTH_OOK;
1576		break;
1577	case NFC_DIGITAL_RF_TECH_212F:
1578		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1579		    TRF7970A_ISO_CTRL_NFC_NFCF_212;
1580		trf->modulator_sys_clk_ctrl =
1581		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1582		    TRF7970A_MODULATOR_DEPTH_ASK10;
1583		break;
1584	case NFC_DIGITAL_RF_TECH_424F:
1585		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1586		    TRF7970A_ISO_CTRL_NFC_NFCF_424;
1587		trf->modulator_sys_clk_ctrl =
1588		    (trf->modulator_sys_clk_ctrl & 0xf8) |
1589		    TRF7970A_MODULATOR_DEPTH_ASK10;
1590		break;
1591	default:
1592		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1593		return -EINVAL;
1594	}
1595
1596	trf->technology = tech;
1597
1598	/* Normally we write the ISO_CTRL register in
1599	 * trf7970a_tg_config_framing() because the framing can change
1600	 * the value written.  However, when sending a PSL RES,
1601	 * digital_tg_send_psl_res_complete() doesn't call
1602	 * trf7970a_tg_config_framing() so we must write the register
1603	 * here.
1604	 */
1605	if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1606	    (trf->iso_ctrl_tech != trf->iso_ctrl)) {
1607		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1608				     trf->iso_ctrl_tech);
1609
1610		trf->iso_ctrl = trf->iso_ctrl_tech;
1611	}
1612
1613	return ret;
1614}
1615
1616/* Since this is a target routine, several of the framing calls are
1617 * made between receiving the request and sending the response so they
1618 * should take effect until after the response is sent.  This is accomplished
1619 * by skipping the ISO_CTRL register write here and doing it in the interrupt
1620 * handler.
1621 */
1622static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1623{
1624	u8 iso_ctrl = trf->iso_ctrl_tech;
1625	int ret;
1626
1627	dev_dbg(trf->dev, "framing: %d\n", framing);
1628
1629	switch (framing) {
1630	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1631		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1632		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1633		break;
1634	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1635	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1636	case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1637		/* These ones are applied in the interrupt handler */
1638		iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1639		break;
1640	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1641		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1642		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1643		break;
1644	case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1645		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1646		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1647		break;
1648	default:
1649		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1650		return -EINVAL;
1651	}
1652
1653	trf->framing = framing;
1654
1655	if (iso_ctrl != trf->iso_ctrl) {
1656		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1657		if (ret)
1658			return ret;
1659
1660		trf->iso_ctrl = iso_ctrl;
1661
1662		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1663				     trf->modulator_sys_clk_ctrl);
1664		if (ret)
1665			return ret;
1666	}
1667
1668	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1669		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1670				     trf->chip_status_ctrl |
1671				     TRF7970A_CHIP_STATUS_RF_ON);
1672		if (ret)
1673			return ret;
1674
1675		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1676	}
1677
1678	return 0;
1679}
1680
1681static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1682				    int param)
1683{
1684	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1685	int ret;
1686
1687	dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1688
1689	mutex_lock(&trf->lock);
1690
1691	trf->is_initiator = false;
1692
1693	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1694	    (trf->state == TRF7970A_ST_RF_OFF)) {
1695		ret = trf7970a_switch_rf_on(trf);
1696		if (ret)
1697			goto err_unlock;
1698	}
1699
1700	switch (type) {
1701	case NFC_DIGITAL_CONFIG_RF_TECH:
1702		ret = trf7970a_tg_config_rf_tech(trf, param);
1703		break;
1704	case NFC_DIGITAL_CONFIG_FRAMING:
1705		ret = trf7970a_tg_config_framing(trf, param);
1706		break;
1707	default:
1708		dev_dbg(trf->dev, "Unknown type: %d\n", type);
1709		ret = -EINVAL;
1710	}
1711
1712err_unlock:
1713	mutex_unlock(&trf->lock);
1714	return ret;
1715}
1716
1717static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1718			       nfc_digital_cmd_complete_t cb, void *arg,
1719			       bool mode_detect)
1720{
1721	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1722	int ret;
1723
1724	mutex_lock(&trf->lock);
1725
1726	if ((trf->state != TRF7970A_ST_IDLE) &&
1727	    (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1728		dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1729			trf->state);
1730		ret = -EIO;
1731		goto out_err;
1732	}
1733
1734	if (trf->aborting) {
1735		dev_dbg(trf->dev, "Abort process complete\n");
1736		trf->aborting = false;
1737		ret = -ECANCELED;
1738		goto out_err;
1739	}
1740
1741	trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1742					 GFP_KERNEL);
1743	if (!trf->rx_skb) {
1744		dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1745		ret = -ENOMEM;
1746		goto out_err;
1747	}
1748
1749	ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1750			     TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1751			     TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1752			     TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1753			     TRF7970A_RX_SPECIAL_SETTINGS_C212);
1754	if (ret)
1755		goto out_err;
1756
1757	ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1758			     trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1759	if (ret)
1760		goto out_err;
1761
1762	ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1763			     TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1764	if (ret)
1765		goto out_err;
1766
1767	ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1768			     TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1769	if (ret)
1770		goto out_err;
1771
1772	trf->ddev = ddev;
1773	trf->cb = cb;
1774	trf->cb_arg = arg;
1775	trf->timeout = timeout;
1776	trf->ignore_timeout = false;
1777
1778	ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1779	if (ret)
1780		goto out_err;
1781
1782	trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1783				   TRF7970A_ST_LISTENING;
1784
1785	schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1786
1787out_err:
1788	mutex_unlock(&trf->lock);
1789	return ret;
1790}
1791
1792static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1793			      nfc_digital_cmd_complete_t cb, void *arg)
1794{
1795	const struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1796
1797	dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1798		trf->state, timeout);
1799
1800	return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1801}
1802
1803static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1804				 u16 timeout, nfc_digital_cmd_complete_t cb,
1805				 void *arg)
1806{
1807	const struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1808	int ret;
1809
1810	dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1811		trf->state, timeout);
1812
1813	ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1814				       NFC_DIGITAL_RF_TECH_106A);
1815	if (ret)
1816		return ret;
1817
1818	ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1819				       NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1820	if (ret)
1821		return ret;
1822
1823	return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1824}
1825
1826static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1827{
1828	const struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1829
1830	dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1831		trf->state, trf->md_rf_tech);
1832
1833	*rf_tech = trf->md_rf_tech;
1834
1835	return 0;
1836}
1837
1838static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1839{
1840	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1841
1842	dev_dbg(trf->dev, "Abort process initiated\n");
1843
1844	mutex_lock(&trf->lock);
1845
1846	switch (trf->state) {
1847	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1848	case TRF7970A_ST_WAIT_FOR_RX_DATA:
1849	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1850	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1851		trf->aborting = true;
1852		break;
1853	case TRF7970A_ST_LISTENING:
1854		trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1855		trf7970a_send_err_upstream(trf, -ECANCELED);
1856		dev_dbg(trf->dev, "Abort process complete\n");
1857		break;
1858	default:
1859		break;
1860	}
1861
1862	mutex_unlock(&trf->lock);
1863}
1864
1865static const struct nfc_digital_ops trf7970a_nfc_ops = {
1866	.in_configure_hw	= trf7970a_in_configure_hw,
1867	.in_send_cmd		= trf7970a_send_cmd,
1868	.tg_configure_hw	= trf7970a_tg_configure_hw,
1869	.tg_send_cmd		= trf7970a_send_cmd,
1870	.tg_listen		= trf7970a_tg_listen,
1871	.tg_listen_md		= trf7970a_tg_listen_md,
1872	.tg_get_rf_tech		= trf7970a_tg_get_rf_tech,
1873	.switch_rf		= trf7970a_switch_rf,
1874	.abort_cmd		= trf7970a_abort_cmd,
1875};
1876
1877static int trf7970a_power_up(struct trf7970a *trf)
1878{
1879	int ret;
1880
1881	dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1882
1883	if (trf->state != TRF7970A_ST_PWR_OFF)
1884		return 0;
1885
1886	ret = regulator_enable(trf->regulator);
1887	if (ret) {
1888		dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1889		return ret;
1890	}
1891
1892	usleep_range(5000, 6000);
1893
1894	if (trf->en2_gpiod &&
1895	    !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1896		gpiod_set_value_cansleep(trf->en2_gpiod, 1);
1897		usleep_range(1000, 2000);
1898	}
1899
1900	gpiod_set_value_cansleep(trf->en_gpiod, 1);
1901
1902	usleep_range(20000, 21000);
1903
1904	trf->state = TRF7970A_ST_RF_OFF;
1905
1906	return 0;
1907}
1908
1909static int trf7970a_power_down(struct trf7970a *trf)
1910{
1911	int ret;
1912
1913	dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1914
1915	if (trf->state == TRF7970A_ST_PWR_OFF)
1916		return 0;
1917
1918	if (trf->state != TRF7970A_ST_RF_OFF) {
1919		dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1920			trf->state);
1921		return -EBUSY;
1922	}
1923
1924	gpiod_set_value_cansleep(trf->en_gpiod, 0);
1925
1926	if (trf->en2_gpiod && !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW))
1927		gpiod_set_value_cansleep(trf->en2_gpiod, 0);
1928
1929	ret = regulator_disable(trf->regulator);
1930	if (ret)
1931		dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1932			ret);
1933
1934	trf->state = TRF7970A_ST_PWR_OFF;
1935
1936	return ret;
1937}
1938
1939static int trf7970a_startup(struct trf7970a *trf)
1940{
1941	int ret;
1942
1943	ret = trf7970a_power_up(trf);
1944	if (ret)
1945		return ret;
1946
1947	pm_runtime_set_active(trf->dev);
1948	pm_runtime_enable(trf->dev);
1949	pm_runtime_mark_last_busy(trf->dev);
1950
1951	return 0;
1952}
1953
1954static void trf7970a_shutdown(struct trf7970a *trf)
1955{
1956	switch (trf->state) {
1957	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1958	case TRF7970A_ST_WAIT_FOR_RX_DATA:
1959	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1960	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1961	case TRF7970A_ST_LISTENING:
1962		trf7970a_send_err_upstream(trf, -ECANCELED);
1963		fallthrough;
1964	case TRF7970A_ST_IDLE:
1965	case TRF7970A_ST_IDLE_RX_BLOCKED:
1966		trf7970a_switch_rf_off(trf);
1967		break;
1968	default:
1969		break;
1970	}
1971
1972	pm_runtime_disable(trf->dev);
1973	pm_runtime_set_suspended(trf->dev);
1974
1975	trf7970a_power_down(trf);
1976}
1977
1978static int trf7970a_get_autosuspend_delay(const struct device_node *np)
1979{
1980	int autosuspend_delay, ret;
1981
1982	ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
1983	if (ret)
1984		autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
1985
1986	return autosuspend_delay;
1987}
1988
 
 
 
 
 
 
1989static int trf7970a_probe(struct spi_device *spi)
1990{
1991	const struct device_node *np = spi->dev.of_node;
1992	struct trf7970a *trf;
1993	int uvolts, autosuspend_delay, ret;
1994	u32 clk_freq = TRF7970A_13MHZ_CLOCK_FREQUENCY;
1995
1996	if (!np) {
1997		dev_err(&spi->dev, "No Device Tree entry\n");
1998		return -EINVAL;
1999	}
2000
2001	trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
2002	if (!trf)
2003		return -ENOMEM;
2004
2005	trf->state = TRF7970A_ST_PWR_OFF;
2006	trf->dev = &spi->dev;
2007	trf->spi = spi;
2008
2009	spi->mode = SPI_MODE_1;
2010	spi->bits_per_word = 8;
2011
2012	ret = spi_setup(spi);
2013	if (ret < 0) {
2014		dev_err(trf->dev, "Can't set up SPI Communication\n");
2015		return ret;
2016	}
2017
 
 
 
2018	if (of_property_read_bool(np, "irq-status-read-quirk"))
2019		trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
2020
2021	/* There are two enable pins - only EN must be present in the DT */
2022	trf->en_gpiod = devm_gpiod_get_index(trf->dev, "ti,enable", 0,
2023					     GPIOD_OUT_LOW);
2024	if (IS_ERR(trf->en_gpiod)) {
2025		dev_err(trf->dev, "No EN GPIO property\n");
2026		return PTR_ERR(trf->en_gpiod);
2027	}
2028
2029	trf->en2_gpiod = devm_gpiod_get_index_optional(trf->dev, "ti,enable", 1,
2030						       GPIOD_OUT_LOW);
2031	if (!trf->en2_gpiod) {
2032		dev_info(trf->dev, "No EN2 GPIO property\n");
2033	} else if (IS_ERR(trf->en2_gpiod)) {
2034		dev_err(trf->dev, "Error getting EN2 GPIO property: %ld\n",
2035			PTR_ERR(trf->en2_gpiod));
2036		return PTR_ERR(trf->en2_gpiod);
2037	} else if (of_property_read_bool(np, "en2-rf-quirk")) {
2038		trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2039	}
2040
2041	of_property_read_u32(np, "clock-frequency", &clk_freq);
2042	if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) &&
2043	    (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
2044		dev_err(trf->dev,
2045			"clock-frequency (%u Hz) unsupported\n", clk_freq);
2046		return -EINVAL;
2047	}
2048
2049	if (clk_freq == TRF7970A_27MHZ_CLOCK_FREQUENCY) {
2050		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
2051		dev_dbg(trf->dev, "trf7970a configured for 27MHz crystal\n");
2052	} else {
2053		trf->modulator_sys_clk_ctrl = 0;
2054	}
2055
 
 
 
2056	ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2057					trf7970a_irq,
2058					IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2059					"trf7970a", trf);
2060	if (ret) {
2061		dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2062		return ret;
2063	}
2064
2065	mutex_init(&trf->lock);
2066	INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2067
2068	trf->regulator = devm_regulator_get(&spi->dev, "vin");
2069	if (IS_ERR(trf->regulator)) {
2070		ret = PTR_ERR(trf->regulator);
2071		dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2072		goto err_destroy_lock;
2073	}
2074
2075	ret = regulator_enable(trf->regulator);
2076	if (ret) {
2077		dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2078		goto err_destroy_lock;
2079	}
2080
2081	uvolts = regulator_get_voltage(trf->regulator);
 
 
 
2082	if (uvolts > 4000000)
2083		trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2084
2085	trf->regulator = devm_regulator_get(&spi->dev, "vdd-io");
2086	if (IS_ERR(trf->regulator)) {
2087		ret = PTR_ERR(trf->regulator);
2088		dev_err(trf->dev, "Can't get VDD_IO regulator: %d\n", ret);
2089		goto err_destroy_lock;
2090	}
2091
2092	ret = regulator_enable(trf->regulator);
2093	if (ret) {
2094		dev_err(trf->dev, "Can't enable VDD_IO: %d\n", ret);
2095		goto err_destroy_lock;
2096	}
2097
2098	if (regulator_get_voltage(trf->regulator) == 1800000) {
2099		trf->io_ctrl = TRF7970A_REG_IO_CTRL_IO_LOW;
2100		dev_dbg(trf->dev, "trf7970a config vdd_io to 1.8V\n");
2101	}
2102
2103	trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2104						TRF7970A_SUPPORTED_PROTOCOLS,
2105						NFC_DIGITAL_DRV_CAPS_IN_CRC |
2106						NFC_DIGITAL_DRV_CAPS_TG_CRC, 0,
2107						0);
2108	if (!trf->ddev) {
2109		dev_err(trf->dev, "Can't allocate NFC digital device\n");
2110		ret = -ENOMEM;
2111		goto err_disable_regulator;
2112	}
2113
2114	nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2115	nfc_digital_set_drvdata(trf->ddev, trf);
2116	spi_set_drvdata(spi, trf);
2117
2118	autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2119
2120	pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2121	pm_runtime_use_autosuspend(trf->dev);
2122
2123	ret = trf7970a_startup(trf);
2124	if (ret)
2125		goto err_free_ddev;
2126
2127	ret = nfc_digital_register_device(trf->ddev);
2128	if (ret) {
2129		dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2130			ret);
2131		goto err_shutdown;
2132	}
2133
2134	return 0;
2135
2136err_shutdown:
2137	trf7970a_shutdown(trf);
2138err_free_ddev:
2139	nfc_digital_free_device(trf->ddev);
2140err_disable_regulator:
2141	regulator_disable(trf->regulator);
2142err_destroy_lock:
2143	mutex_destroy(&trf->lock);
2144	return ret;
2145}
2146
2147static void trf7970a_remove(struct spi_device *spi)
2148{
2149	struct trf7970a *trf = spi_get_drvdata(spi);
2150
2151	mutex_lock(&trf->lock);
2152
2153	trf7970a_shutdown(trf);
2154
2155	mutex_unlock(&trf->lock);
2156
2157	nfc_digital_unregister_device(trf->ddev);
2158	nfc_digital_free_device(trf->ddev);
2159
2160	regulator_disable(trf->regulator);
2161
2162	mutex_destroy(&trf->lock);
 
 
2163}
2164
2165#ifdef CONFIG_PM_SLEEP
2166static int trf7970a_suspend(struct device *dev)
2167{
2168	struct spi_device *spi = to_spi_device(dev);
2169	struct trf7970a *trf = spi_get_drvdata(spi);
2170
 
 
2171	mutex_lock(&trf->lock);
2172
2173	trf7970a_shutdown(trf);
2174
2175	mutex_unlock(&trf->lock);
2176
2177	return 0;
2178}
2179
2180static int trf7970a_resume(struct device *dev)
2181{
2182	struct spi_device *spi = to_spi_device(dev);
2183	struct trf7970a *trf = spi_get_drvdata(spi);
2184	int ret;
2185
 
 
2186	mutex_lock(&trf->lock);
2187
2188	ret = trf7970a_startup(trf);
2189
2190	mutex_unlock(&trf->lock);
2191
2192	return ret;
2193}
2194#endif
2195
2196#ifdef CONFIG_PM
2197static int trf7970a_pm_runtime_suspend(struct device *dev)
2198{
2199	struct spi_device *spi = to_spi_device(dev);
2200	struct trf7970a *trf = spi_get_drvdata(spi);
2201	int ret;
2202
 
 
2203	mutex_lock(&trf->lock);
2204
2205	ret = trf7970a_power_down(trf);
2206
2207	mutex_unlock(&trf->lock);
2208
2209	return ret;
2210}
2211
2212static int trf7970a_pm_runtime_resume(struct device *dev)
2213{
2214	struct spi_device *spi = to_spi_device(dev);
2215	struct trf7970a *trf = spi_get_drvdata(spi);
2216	int ret;
2217
 
 
2218	ret = trf7970a_power_up(trf);
2219	if (!ret)
2220		pm_runtime_mark_last_busy(dev);
2221
2222	return ret;
2223}
2224#endif
2225
2226static const struct dev_pm_ops trf7970a_pm_ops = {
2227	SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2228	SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2229			   trf7970a_pm_runtime_resume, NULL)
2230};
2231
2232static const struct of_device_id trf7970a_of_match[] __maybe_unused = {
2233	{.compatible = "ti,trf7970a",},
2234	{},
2235};
2236
2237MODULE_DEVICE_TABLE(of, trf7970a_of_match);
2238
2239static const struct spi_device_id trf7970a_id_table[] = {
2240	{"trf7970a", 0},
2241	{}
2242};
2243
2244MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2245
2246static struct spi_driver trf7970a_spi_driver = {
2247	.probe		= trf7970a_probe,
2248	.remove		= trf7970a_remove,
2249	.id_table	= trf7970a_id_table,
2250	.driver	= {
2251		.name		= "trf7970a",
2252		.of_match_table	= of_match_ptr(trf7970a_of_match),
2253		.pm		= &trf7970a_pm_ops,
2254	},
2255};
2256
2257module_spi_driver(trf7970a_spi_driver);
2258
2259MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2260MODULE_LICENSE("GPL v2");
2261MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");
v4.10.11
 
   1/*
   2 * TI TRF7970a RFID/NFC Transceiver Driver
   3 *
   4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
   5 *
   6 * Author: Erick Macias <emacias@ti.com>
   7 * Author: Felipe Balbi <balbi@ti.com>
   8 * Author: Mark A. Greer <mgreer@animalcreek.com>
   9 *
  10 * This program is free software: you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License version 2  of
  12 * the License as published by the Free Software Foundation.
  13 */
  14
  15#include <linux/module.h>
  16#include <linux/device.h>
  17#include <linux/netdevice.h>
  18#include <linux/interrupt.h>
  19#include <linux/pm_runtime.h>
  20#include <linux/nfc.h>
  21#include <linux/skbuff.h>
  22#include <linux/delay.h>
  23#include <linux/gpio.h>
  24#include <linux/of.h>
  25#include <linux/of_gpio.h>
  26#include <linux/spi/spi.h>
  27#include <linux/regulator/consumer.h>
  28
  29#include <net/nfc/nfc.h>
  30#include <net/nfc/digital.h>
  31
  32/* There are 3 ways the host can communicate with the trf7970a:
  33 * parallel mode, SPI with Slave Select (SS) mode, and SPI without
  34 * SS mode.  The driver only supports the two SPI modes.
  35 *
  36 * The trf7970a is very timing sensitive and the VIN, EN2, and EN
  37 * pins must asserted in that order and with specific delays in between.
  38 * The delays used in the driver were provided by TI and have been
  39 * confirmed to work with this driver.  There is a bug with the current
  40 * version of the trf7970a that requires that EN2 remain low no matter
  41 * what.  If it goes high, it will generate an RF field even when in
  42 * passive target mode.  TI has indicated that the chip will work okay
  43 * when EN2 is left low.  The 'en2-rf-quirk' device tree property
  44 * indicates that trf7970a currently being used has the erratum and
  45 * that EN2 must be kept low.
  46 *
  47 * Timeouts are implemented using the delayed workqueue kernel facility.
  48 * Timeouts are required so things don't hang when there is no response
  49 * from the trf7970a (or tag).  Using this mechanism creates a race with
  50 * interrupts, however.  That is, an interrupt and a timeout could occur
  51 * closely enough together that one is blocked by the mutex while the other
  52 * executes.  When the timeout handler executes first and blocks the
  53 * interrupt handler, it will eventually set the state to IDLE so the
  54 * interrupt handler will check the state and exit with no harm done.
  55 * When the interrupt handler executes first and blocks the timeout handler,
  56 * the cancel_delayed_work() call will know that it didn't cancel the
  57 * work item (i.e., timeout) and will return zero.  That return code is
  58 * used by the timer handler to indicate that it should ignore the timeout
  59 * once its unblocked.
  60 *
  61 * Aborting an active command isn't as simple as it seems because the only
  62 * way to abort a command that's already been sent to the tag is so turn
  63 * off power to the tag.  If we do that, though, we'd have to go through
  64 * the entire anticollision procedure again but the digital layer doesn't
  65 * support that.  So, if an abort is received before trf7970a_send_cmd()
  66 * has sent the command to the tag, it simply returns -ECANCELED.  If the
  67 * command has already been sent to the tag, then the driver continues
  68 * normally and recieves the response data (or error) but just before
  69 * sending the data upstream, it frees the rx_skb and sends -ECANCELED
  70 * upstream instead.  If the command failed, that error will be sent
  71 * upstream.
  72 *
  73 * When recieving data from a tag and the interrupt status register has
  74 * only the SRX bit set, it means that all of the data has been received
  75 * (once what's in the fifo has been read).  However, depending on timing
  76 * an interrupt status with only the SRX bit set may not be recived.  In
  77 * those cases, the timeout mechanism is used to wait 20 ms in case more
  78 * data arrives.  After 20 ms, it is assumed that all of the data has been
  79 * received and the accumulated rx data is sent upstream.  The
  80 * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
  81 * (i.e., it indicates that some data has been received but we're not sure
  82 * if there is more coming so a timeout in this state means all data has
  83 * been received and there isn't an error).  The delay is 20 ms since delays
  84 * of ~16 ms have been observed during testing.
  85 *
  86 * When transmitting a frame larger than the FIFO size (127 bytes), the
  87 * driver will wait 20 ms for the FIFO to drain past the low-watermark
  88 * and generate an interrupt.  The low-watermark set to 32 bytes so the
  89 * interrupt should fire after 127 - 32 = 95 bytes have been sent.  At
  90 * the lowest possible bit rate (6.62 kbps for 15693), it will take up
  91 * to ~14.35 ms so 20 ms is used for the timeout.
  92 *
  93 * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
  94 * Having only 4 bits in the FIFO won't normally generate an interrupt so
  95 * driver enables the '4_bit_RX' bit of the Special Functions register 1
  96 * to cause an interrupt in that case.  Leaving that bit for a read command
  97 * messes up the data returned so it is only enabled when the framing is
  98 * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
  99 * Unfortunately, that means that the driver has to peek into tx frames
 100 * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'.  This is done by
 101 * the trf7970a_per_cmd_config() routine.
 102 *
 103 * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
 104 * frequencies and whether to use low or high data rates in the flags byte
 105 * of the frame.  This means that the driver has to peek at all 15693 frames
 106 * to determine what speed to set the communication to.  In addition, write
 107 * and lock commands use the OPTION flag to indicate that an EOF must be
 108 * sent to the tag before it will send its response.  So the driver has to
 109 * examine all frames for that reason too.
 110 *
 111 * It is unclear how long to wait before sending the EOF.  According to the
 112 * Note under Table 1-1 in section 1.6 of
 113 * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
 114 * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
 115 * enough so 20 ms is used.  So the timer is set to 40 ms - 20 ms to drain
 116 * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
 117 * ensure the wait is long enough before sending the EOF.  This seems to work
 118 * reliably.
 119 */
 120
 121#define TRF7970A_SUPPORTED_PROTOCOLS \
 122		(NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |	\
 123		 NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
 124		 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
 125
 126#define TRF7970A_AUTOSUSPEND_DELAY		30000 /* 30 seconds */
 
 
 127
 128#define TRF7970A_RX_SKB_ALLOC_SIZE		256
 129
 130#define TRF7970A_FIFO_SIZE			127
 131
 132/* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
 133#define TRF7970A_TX_MAX				(4096 - 1)
 134
 135#define TRF7970A_WAIT_FOR_TX_IRQ		20
 136#define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT	20
 137#define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT	20
 138#define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF	40
 139
 140/* Guard times for various RF technologies (in us) */
 141#define TRF7970A_GUARD_TIME_NFCA		5000
 142#define TRF7970A_GUARD_TIME_NFCB		5000
 143#define TRF7970A_GUARD_TIME_NFCF		20000
 144#define TRF7970A_GUARD_TIME_15693		1000
 145
 146/* Quirks */
 147/* Erratum: When reading IRQ Status register on trf7970a, we must issue a
 148 * read continuous command for IRQ Status and Collision Position registers.
 149 */
 150#define TRF7970A_QUIRK_IRQ_STATUS_READ		BIT(0)
 151#define TRF7970A_QUIRK_EN2_MUST_STAY_LOW	BIT(1)
 152#define TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE	BIT(2)
 153
 154/* Direct commands */
 155#define TRF7970A_CMD_IDLE			0x00
 156#define TRF7970A_CMD_SOFT_INIT			0x03
 157#define TRF7970A_CMD_RF_COLLISION		0x04
 158#define TRF7970A_CMD_RF_COLLISION_RESPONSE_N	0x05
 159#define TRF7970A_CMD_RF_COLLISION_RESPONSE_0	0x06
 160#define TRF7970A_CMD_FIFO_RESET			0x0f
 161#define TRF7970A_CMD_TRANSMIT_NO_CRC		0x10
 162#define TRF7970A_CMD_TRANSMIT			0x11
 163#define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC	0x12
 164#define TRF7970A_CMD_DELAY_TRANSMIT		0x13
 165#define TRF7970A_CMD_EOF			0x14
 166#define TRF7970A_CMD_CLOSE_SLOT			0x15
 167#define TRF7970A_CMD_BLOCK_RX			0x16
 168#define TRF7970A_CMD_ENABLE_RX			0x17
 169#define TRF7970A_CMD_TEST_INT_RF		0x18
 170#define TRF7970A_CMD_TEST_EXT_RF		0x19
 171#define TRF7970A_CMD_RX_GAIN_ADJUST		0x1a
 172
 173/* Bits determining whether its a direct command or register R/W,
 174 * whether to use a continuous SPI transaction or not, and the actual
 175 * direct cmd opcode or regster address.
 176 */
 177#define TRF7970A_CMD_BIT_CTRL			BIT(7)
 178#define TRF7970A_CMD_BIT_RW			BIT(6)
 179#define TRF7970A_CMD_BIT_CONTINUOUS		BIT(5)
 180#define TRF7970A_CMD_BIT_OPCODE(opcode)		((opcode) & 0x1f)
 181
 182/* Registers addresses */
 183#define TRF7970A_CHIP_STATUS_CTRL		0x00
 184#define TRF7970A_ISO_CTRL			0x01
 185#define TRF7970A_ISO14443B_TX_OPTIONS		0x02
 186#define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS	0x03
 187#define TRF7970A_TX_TIMER_SETTING_H_BYTE	0x04
 188#define TRF7970A_TX_TIMER_SETTING_L_BYTE	0x05
 189#define TRF7970A_TX_PULSE_LENGTH_CTRL		0x06
 190#define TRF7970A_RX_NO_RESPONSE_WAIT		0x07
 191#define TRF7970A_RX_WAIT_TIME			0x08
 192#define TRF7970A_MODULATOR_SYS_CLK_CTRL		0x09
 193#define TRF7970A_RX_SPECIAL_SETTINGS		0x0a
 194#define TRF7970A_REG_IO_CTRL			0x0b
 195#define TRF7970A_IRQ_STATUS			0x0c
 196#define TRF7970A_COLLISION_IRQ_MASK		0x0d
 197#define TRF7970A_COLLISION_POSITION		0x0e
 198#define TRF7970A_RSSI_OSC_STATUS		0x0f
 199#define TRF7970A_SPECIAL_FCN_REG1		0x10
 200#define TRF7970A_SPECIAL_FCN_REG2		0x11
 201#define TRF7970A_RAM1				0x12
 202#define TRF7970A_RAM2				0x13
 203#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS	0x14
 204#define TRF7970A_NFC_LOW_FIELD_LEVEL		0x16
 205#define TRF7970A_NFCID1				0x17
 206#define TRF7970A_NFC_TARGET_LEVEL		0x18
 207#define TRF79070A_NFC_TARGET_PROTOCOL		0x19
 208#define TRF7970A_TEST_REGISTER1			0x1a
 209#define TRF7970A_TEST_REGISTER2			0x1b
 210#define TRF7970A_FIFO_STATUS			0x1c
 211#define TRF7970A_TX_LENGTH_BYTE1		0x1d
 212#define TRF7970A_TX_LENGTH_BYTE2		0x1e
 213#define TRF7970A_FIFO_IO_REGISTER		0x1f
 214
 215/* Chip Status Control Register Bits */
 216#define TRF7970A_CHIP_STATUS_VRS5_3		BIT(0)
 217#define TRF7970A_CHIP_STATUS_REC_ON		BIT(1)
 218#define TRF7970A_CHIP_STATUS_AGC_ON		BIT(2)
 219#define TRF7970A_CHIP_STATUS_PM_ON		BIT(3)
 220#define TRF7970A_CHIP_STATUS_RF_PWR		BIT(4)
 221#define TRF7970A_CHIP_STATUS_RF_ON		BIT(5)
 222#define TRF7970A_CHIP_STATUS_DIRECT		BIT(6)
 223#define TRF7970A_CHIP_STATUS_STBY		BIT(7)
 224
 225/* ISO Control Register Bits */
 226#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662	0x00
 227#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662	0x01
 228#define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648	0x02
 229#define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648	0x03
 230#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a	0x04
 231#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667	0x05
 232#define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669	0x06
 233#define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669	0x07
 234#define TRF7970A_ISO_CTRL_14443A_106		0x08
 235#define TRF7970A_ISO_CTRL_14443A_212		0x09
 236#define TRF7970A_ISO_CTRL_14443A_424		0x0a
 237#define TRF7970A_ISO_CTRL_14443A_848		0x0b
 238#define TRF7970A_ISO_CTRL_14443B_106		0x0c
 239#define TRF7970A_ISO_CTRL_14443B_212		0x0d
 240#define TRF7970A_ISO_CTRL_14443B_424		0x0e
 241#define TRF7970A_ISO_CTRL_14443B_848		0x0f
 242#define TRF7970A_ISO_CTRL_FELICA_212		0x1a
 243#define TRF7970A_ISO_CTRL_FELICA_424		0x1b
 244#define TRF7970A_ISO_CTRL_NFC_NFCA_106		0x01
 245#define TRF7970A_ISO_CTRL_NFC_NFCF_212		0x02
 246#define TRF7970A_ISO_CTRL_NFC_NFCF_424		0x03
 247#define TRF7970A_ISO_CTRL_NFC_CE_14443A		0x00
 248#define TRF7970A_ISO_CTRL_NFC_CE_14443B		0x01
 249#define TRF7970A_ISO_CTRL_NFC_CE		BIT(2)
 250#define TRF7970A_ISO_CTRL_NFC_ACTIVE		BIT(3)
 251#define TRF7970A_ISO_CTRL_NFC_INITIATOR		BIT(4)
 252#define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE	BIT(5)
 253#define TRF7970A_ISO_CTRL_RFID			BIT(5)
 254#define TRF7970A_ISO_CTRL_DIR_MODE		BIT(6)
 255#define TRF7970A_ISO_CTRL_RX_CRC_N		BIT(7)	/* true == No CRC */
 256
 257#define TRF7970A_ISO_CTRL_RFID_SPEED_MASK	0x1f
 258
 259/* Modulator and SYS_CLK Control Register Bits */
 260#define TRF7970A_MODULATOR_DEPTH(n)		((n) & 0x7)
 261#define TRF7970A_MODULATOR_DEPTH_ASK10		(TRF7970A_MODULATOR_DEPTH(0))
 262#define TRF7970A_MODULATOR_DEPTH_OOK		(TRF7970A_MODULATOR_DEPTH(1))
 263#define TRF7970A_MODULATOR_DEPTH_ASK7		(TRF7970A_MODULATOR_DEPTH(2))
 264#define TRF7970A_MODULATOR_DEPTH_ASK8_5		(TRF7970A_MODULATOR_DEPTH(3))
 265#define TRF7970A_MODULATOR_DEPTH_ASK13		(TRF7970A_MODULATOR_DEPTH(4))
 266#define TRF7970A_MODULATOR_DEPTH_ASK16		(TRF7970A_MODULATOR_DEPTH(5))
 267#define TRF7970A_MODULATOR_DEPTH_ASK22		(TRF7970A_MODULATOR_DEPTH(6))
 268#define TRF7970A_MODULATOR_DEPTH_ASK30		(TRF7970A_MODULATOR_DEPTH(7))
 269#define TRF7970A_MODULATOR_EN_ANA		BIT(3)
 270#define TRF7970A_MODULATOR_CLK(n)		(((n) & 0x3) << 4)
 271#define TRF7970A_MODULATOR_CLK_DISABLED		(TRF7970A_MODULATOR_CLK(0))
 272#define TRF7970A_MODULATOR_CLK_3_6		(TRF7970A_MODULATOR_CLK(1))
 273#define TRF7970A_MODULATOR_CLK_6_13		(TRF7970A_MODULATOR_CLK(2))
 274#define TRF7970A_MODULATOR_CLK_13_27		(TRF7970A_MODULATOR_CLK(3))
 275#define TRF7970A_MODULATOR_EN_OOK		BIT(6)
 276#define TRF7970A_MODULATOR_27MHZ		BIT(7)
 277
 278#define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM	BIT(0)
 279#define TRF7970A_RX_SPECIAL_SETTINGS_AGCR	BIT(1)
 280#define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB	(0x0 << 2)
 281#define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB	(0x1 << 2)
 282#define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB	(0x2 << 2)
 283#define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB	(0x3 << 2)
 284#define TRF7970A_RX_SPECIAL_SETTINGS_HBT	BIT(4)
 285#define TRF7970A_RX_SPECIAL_SETTINGS_M848	BIT(5)
 286#define TRF7970A_RX_SPECIAL_SETTINGS_C424	BIT(6)
 287#define TRF7970A_RX_SPECIAL_SETTINGS_C212	BIT(7)
 288
 289#define TRF7970A_REG_IO_CTRL_VRS(v)		((v) & 0x07)
 290#define TRF7970A_REG_IO_CTRL_IO_LOW		BIT(5)
 291#define TRF7970A_REG_IO_CTRL_EN_EXT_PA		BIT(6)
 292#define TRF7970A_REG_IO_CTRL_AUTO_REG		BIT(7)
 293
 294/* IRQ Status Register Bits */
 295#define TRF7970A_IRQ_STATUS_NORESP		BIT(0) /* ISO15693 only */
 296#define TRF7970A_IRQ_STATUS_NFC_COL_ERROR	BIT(0)
 297#define TRF7970A_IRQ_STATUS_COL			BIT(1)
 298#define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR	BIT(2)
 299#define TRF7970A_IRQ_STATUS_NFC_RF		BIT(2)
 300#define TRF7970A_IRQ_STATUS_PARITY_ERROR	BIT(3)
 301#define TRF7970A_IRQ_STATUS_NFC_SDD		BIT(3)
 302#define TRF7970A_IRQ_STATUS_CRC_ERROR		BIT(4)
 303#define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR	BIT(4)
 304#define TRF7970A_IRQ_STATUS_FIFO		BIT(5)
 305#define TRF7970A_IRQ_STATUS_SRX			BIT(6)
 306#define TRF7970A_IRQ_STATUS_TX			BIT(7)
 307
 308#define TRF7970A_IRQ_STATUS_ERROR				\
 309		(TRF7970A_IRQ_STATUS_COL |			\
 310		 TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR |	\
 311		 TRF7970A_IRQ_STATUS_PARITY_ERROR |		\
 312		 TRF7970A_IRQ_STATUS_CRC_ERROR)
 313
 314#define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK	(BIT(2) | BIT(1) | BIT(0))
 315#define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK	(BIT(5) | BIT(4) | BIT(3))
 316#define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK	BIT(6)
 317
 318#define TRF7970A_SPECIAL_FCN_REG1_COL_7_6		BIT(0)
 319#define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL		BIT(1)
 320#define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX		BIT(2)
 321#define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE		BIT(3)
 322#define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US	BIT(4)
 323#define TRF7970A_SPECIAL_FCN_REG1_PAR43			BIT(5)
 324
 325#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124	(0x0 << 2)
 326#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120	(0x1 << 2)
 327#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112	(0x2 << 2)
 328#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96	(0x3 << 2)
 329#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4	0x0
 330#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8	0x1
 331#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16	0x2
 332#define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32	0x3
 333
 334#define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v)	((v) & 0x07)
 335#define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS	BIT(7)
 336
 337#define TRF7970A_NFC_TARGET_LEVEL_RFDET(v)	((v) & 0x07)
 338#define TRF7970A_NFC_TARGET_LEVEL_HI_RF		BIT(3)
 339#define TRF7970A_NFC_TARGET_LEVEL_SDD_EN	BIT(5)
 340#define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES	(0x0 << 6)
 341#define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES	(0x1 << 6)
 342#define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES	(0x2 << 6)
 343
 344#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106		BIT(0)
 345#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212		BIT(1)
 346#define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424		(BIT(0) | BIT(1))
 347#define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B	BIT(2)
 348#define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106		BIT(3)
 349#define TRF79070A_NFC_TARGET_PROTOCOL_FELICA		BIT(4)
 350#define TRF79070A_NFC_TARGET_PROTOCOL_RF_L		BIT(6)
 351#define TRF79070A_NFC_TARGET_PROTOCOL_RF_H		BIT(7)
 352
 353#define TRF79070A_NFC_TARGET_PROTOCOL_106A		\
 354	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 355	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 356	  TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 |	\
 357	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 358
 359#define TRF79070A_NFC_TARGET_PROTOCOL_106B		\
 360	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 361	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 362	  TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B |	\
 363	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 364
 365#define TRF79070A_NFC_TARGET_PROTOCOL_212F		\
 366	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 367	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 368	  TRF79070A_NFC_TARGET_PROTOCOL_FELICA |	\
 369	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
 370
 371#define TRF79070A_NFC_TARGET_PROTOCOL_424F		\
 372	 (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |		\
 373	  TRF79070A_NFC_TARGET_PROTOCOL_RF_L |		\
 374	  TRF79070A_NFC_TARGET_PROTOCOL_FELICA |	\
 375	  TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424)
 376
 377#define TRF7970A_FIFO_STATUS_OVERFLOW		BIT(7)
 378
 379/* NFC (ISO/IEC 14443A) Type 2 Tag commands */
 380#define NFC_T2T_CMD_READ			0x30
 381
 382/* ISO 15693 commands codes */
 383#define ISO15693_CMD_INVENTORY			0x01
 384#define ISO15693_CMD_READ_SINGLE_BLOCK		0x20
 385#define ISO15693_CMD_WRITE_SINGLE_BLOCK		0x21
 386#define ISO15693_CMD_LOCK_BLOCK			0x22
 387#define ISO15693_CMD_READ_MULTIPLE_BLOCK	0x23
 388#define ISO15693_CMD_WRITE_MULTIPLE_BLOCK	0x24
 389#define ISO15693_CMD_SELECT			0x25
 390#define ISO15693_CMD_RESET_TO_READY		0x26
 391#define ISO15693_CMD_WRITE_AFI			0x27
 392#define ISO15693_CMD_LOCK_AFI			0x28
 393#define ISO15693_CMD_WRITE_DSFID		0x29
 394#define ISO15693_CMD_LOCK_DSFID			0x2a
 395#define ISO15693_CMD_GET_SYSTEM_INFO		0x2b
 396#define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS	0x2c
 397
 398/* ISO 15693 request and response flags */
 399#define ISO15693_REQ_FLAG_SUB_CARRIER		BIT(0)
 400#define ISO15693_REQ_FLAG_DATA_RATE		BIT(1)
 401#define ISO15693_REQ_FLAG_INVENTORY		BIT(2)
 402#define ISO15693_REQ_FLAG_PROTOCOL_EXT		BIT(3)
 403#define ISO15693_REQ_FLAG_SELECT		BIT(4)
 404#define ISO15693_REQ_FLAG_AFI			BIT(4)
 405#define ISO15693_REQ_FLAG_ADDRESS		BIT(5)
 406#define ISO15693_REQ_FLAG_NB_SLOTS		BIT(5)
 407#define ISO15693_REQ_FLAG_OPTION		BIT(6)
 408
 409#define ISO15693_REQ_FLAG_SPEED_MASK \
 410		(ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
 411
 412enum trf7970a_state {
 413	TRF7970A_ST_PWR_OFF,
 414	TRF7970A_ST_RF_OFF,
 415	TRF7970A_ST_IDLE,
 416	TRF7970A_ST_IDLE_RX_BLOCKED,
 417	TRF7970A_ST_WAIT_FOR_TX_FIFO,
 418	TRF7970A_ST_WAIT_FOR_RX_DATA,
 419	TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
 420	TRF7970A_ST_WAIT_TO_ISSUE_EOF,
 421	TRF7970A_ST_LISTENING,
 422	TRF7970A_ST_LISTENING_MD,
 423	TRF7970A_ST_MAX
 424};
 425
 426struct trf7970a {
 427	enum trf7970a_state		state;
 428	struct device			*dev;
 429	struct spi_device		*spi;
 430	struct regulator		*regulator;
 431	struct nfc_digital_dev		*ddev;
 432	u32				quirks;
 433	bool				is_initiator;
 434	bool				aborting;
 435	struct sk_buff			*tx_skb;
 436	struct sk_buff			*rx_skb;
 437	nfc_digital_cmd_complete_t	cb;
 438	void				*cb_arg;
 439	u8				chip_status_ctrl;
 440	u8				iso_ctrl;
 441	u8				iso_ctrl_tech;
 442	u8				modulator_sys_clk_ctrl;
 443	u8				special_fcn_reg1;
 
 444	unsigned int			guard_time;
 445	int				technology;
 446	int				framing;
 447	u8				md_rf_tech;
 448	u8				tx_cmd;
 449	bool				issue_eof;
 450	bool				adjust_resp_len;
 451	int				en2_gpio;
 452	int				en_gpio;
 453	struct mutex			lock;
 454	unsigned int			timeout;
 455	bool				ignore_timeout;
 456	struct delayed_work		timeout_work;
 457};
 458
 459
 460static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
 461{
 462	u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
 463	int ret;
 464
 465	dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
 466
 467	ret = spi_write(trf->spi, &cmd, 1);
 468	if (ret)
 469		dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
 470				ret);
 471	return ret;
 472}
 473
 474static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
 475{
 476	u8 addr = TRF7970A_CMD_BIT_RW | reg;
 477	int ret;
 478
 479	ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
 480	if (ret)
 481		dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 482				ret);
 483
 484	dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
 485
 486	return ret;
 487}
 488
 489static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf, size_t len)
 
 490{
 491	u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
 492	struct spi_transfer t[2];
 493	struct spi_message m;
 494	int ret;
 495
 496	dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
 497
 498	spi_message_init(&m);
 499
 500	memset(&t, 0, sizeof(t));
 501
 502	t[0].tx_buf = &addr;
 503	t[0].len = sizeof(addr);
 504	spi_message_add_tail(&t[0], &m);
 505
 506	t[1].rx_buf = buf;
 507	t[1].len = len;
 508	spi_message_add_tail(&t[1], &m);
 509
 510	ret = spi_sync(trf->spi, &m);
 511	if (ret)
 512		dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 513				ret);
 514	return ret;
 515}
 516
 517static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
 518{
 519	u8 buf[2] = { reg, val };
 520	int ret;
 521
 522	dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
 523
 524	ret = spi_write(trf->spi, buf, 2);
 525	if (ret)
 526		dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
 527				buf[0], buf[1], ret);
 528
 529	return ret;
 530}
 531
 532static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
 533{
 534	int ret;
 535	u8 buf[2];
 536	u8 addr;
 537
 538	addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
 539
 540	if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
 541		addr |= TRF7970A_CMD_BIT_CONTINUOUS;
 542		ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 543	} else {
 544		ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
 545	}
 546
 547	if (ret)
 548		dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
 549				__func__, ret);
 550	else
 551		*status = buf[0];
 552
 553	return ret;
 554}
 555
 556static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
 557{
 558	int ret;
 559	u8 buf[2];
 560	u8 addr;
 561
 562	addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
 563		TRF7970A_CMD_BIT_CONTINUOUS;
 564
 565	ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 566	if (ret)
 567		dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
 568				__func__, ret);
 569	else
 570		*target_proto = buf[0];
 571
 572	return ret;
 573}
 574
 575static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
 576{
 577	int ret;
 578	u8 target_proto, tech;
 579
 580	ret = trf7970a_read_target_proto(trf, &target_proto);
 581	if (ret)
 582		return ret;
 583
 584	switch (target_proto) {
 585	case TRF79070A_NFC_TARGET_PROTOCOL_106A:
 586		tech = NFC_DIGITAL_RF_TECH_106A;
 587		break;
 588	case TRF79070A_NFC_TARGET_PROTOCOL_106B:
 589		tech = NFC_DIGITAL_RF_TECH_106B;
 590		break;
 591	case TRF79070A_NFC_TARGET_PROTOCOL_212F:
 592		tech = NFC_DIGITAL_RF_TECH_212F;
 593		break;
 594	case TRF79070A_NFC_TARGET_PROTOCOL_424F:
 595		tech = NFC_DIGITAL_RF_TECH_424F;
 596		break;
 597	default:
 598		dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
 599				__func__, target_proto);
 600		return -EIO;
 601	}
 602
 603	*rf_tech = tech;
 604
 605	return ret;
 606}
 607
 608static void trf7970a_send_upstream(struct trf7970a *trf)
 609{
 610	dev_kfree_skb_any(trf->tx_skb);
 611	trf->tx_skb = NULL;
 612
 613	if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
 614		print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
 615				16, 1, trf->rx_skb->data, trf->rx_skb->len,
 616				false);
 617
 618	trf->state = TRF7970A_ST_IDLE;
 619
 620	if (trf->aborting) {
 621		dev_dbg(trf->dev, "Abort process complete\n");
 622
 623		if (!IS_ERR(trf->rx_skb)) {
 624			kfree_skb(trf->rx_skb);
 625			trf->rx_skb = ERR_PTR(-ECANCELED);
 626		}
 627
 628		trf->aborting = false;
 629	}
 630
 631	if (trf->adjust_resp_len) {
 632		if (trf->rx_skb)
 633			skb_trim(trf->rx_skb, trf->rx_skb->len - 1);
 634
 635		trf->adjust_resp_len = false;
 636	}
 637
 638	trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
 639
 640	trf->rx_skb = NULL;
 641}
 642
 643static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
 644{
 645	dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
 646
 647	cancel_delayed_work(&trf->timeout_work);
 648
 649	kfree_skb(trf->rx_skb);
 650	trf->rx_skb = ERR_PTR(errno);
 651
 652	trf7970a_send_upstream(trf);
 653}
 654
 655static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
 656		unsigned int len, u8 *prefix, unsigned int prefix_len)
 
 657{
 658	struct spi_transfer t[2];
 659	struct spi_message m;
 660	unsigned int timeout;
 661	int ret;
 662
 663	print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
 664			16, 1, skb->data, len, false);
 665
 666	spi_message_init(&m);
 667
 668	memset(&t, 0, sizeof(t));
 669
 670	t[0].tx_buf = prefix;
 671	t[0].len = prefix_len;
 672	spi_message_add_tail(&t[0], &m);
 673
 674	t[1].tx_buf = skb->data;
 675	t[1].len = len;
 676	spi_message_add_tail(&t[1], &m);
 677
 678	ret = spi_sync(trf->spi, &m);
 679	if (ret) {
 680		dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
 681				ret);
 682		return ret;
 683	}
 684
 685	skb_pull(skb, len);
 686
 687	if (skb->len > 0) {
 688		trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
 689		timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
 690	} else {
 691		if (trf->issue_eof) {
 692			trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
 693			timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
 694		} else {
 695			trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
 696
 697			if (!trf->timeout)
 698				timeout = TRF7970A_WAIT_FOR_TX_IRQ;
 699			else
 700				timeout = trf->timeout;
 701		}
 702	}
 703
 704	dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
 705			trf->state);
 706
 707	schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
 708
 709	return 0;
 710}
 711
 712static void trf7970a_fill_fifo(struct trf7970a *trf)
 713{
 714	struct sk_buff *skb = trf->tx_skb;
 715	unsigned int len;
 716	int ret;
 717	u8 fifo_bytes;
 718	u8 prefix;
 719
 720	ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 721	if (ret) {
 722		trf7970a_send_err_upstream(trf, ret);
 723		return;
 724	}
 725
 726	dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 727
 728	fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 729
 730	/* Calculate how much more data can be written to the fifo */
 731	len = TRF7970A_FIFO_SIZE - fifo_bytes;
 732	if (!len) {
 733		schedule_delayed_work(&trf->timeout_work,
 734			msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
 735		return;
 736	}
 737
 738	len = min(skb->len, len);
 739
 740	prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
 741
 742	ret = trf7970a_transmit(trf, skb, len, &prefix, sizeof(prefix));
 743	if (ret)
 744		trf7970a_send_err_upstream(trf, ret);
 745}
 746
 747static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
 748{
 749	struct sk_buff *skb = trf->rx_skb;
 750	int ret;
 751	u8 fifo_bytes;
 752
 753	if (status & TRF7970A_IRQ_STATUS_ERROR) {
 754		trf7970a_send_err_upstream(trf, -EIO);
 755		return;
 756	}
 757
 758	ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 759	if (ret) {
 760		trf7970a_send_err_upstream(trf, ret);
 761		return;
 762	}
 763
 764	dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 765
 766	fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 767
 768	if (!fifo_bytes)
 769		goto no_rx_data;
 770
 771	if (fifo_bytes > skb_tailroom(skb)) {
 772		skb = skb_copy_expand(skb, skb_headroom(skb),
 773				max_t(int, fifo_bytes,
 774					TRF7970A_RX_SKB_ALLOC_SIZE),
 775				GFP_KERNEL);
 776		if (!skb) {
 777			trf7970a_send_err_upstream(trf, -ENOMEM);
 778			return;
 779		}
 780
 781		kfree_skb(trf->rx_skb);
 782		trf->rx_skb = skb;
 783	}
 784
 785	ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
 786			skb_put(skb, fifo_bytes), fifo_bytes);
 787	if (ret) {
 788		trf7970a_send_err_upstream(trf, ret);
 789		return;
 790	}
 791
 792	/* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
 793	if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
 794			(trf->special_fcn_reg1 ==
 795				 TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
 796		skb->data[0] >>= 4;
 797		status = TRF7970A_IRQ_STATUS_SRX;
 798	} else {
 799		trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
 800
 801		ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 802		if (ret) {
 803			trf7970a_send_err_upstream(trf, ret);
 804			return;
 805		}
 806
 807		fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 808
 809		/* If there are bytes in the FIFO, set status to '0' so
 810		 * the if stmt below doesn't fire and the driver will wait
 811		 * for the trf7970a to generate another RX interrupt.
 812		 */
 813		if (fifo_bytes)
 814			status = 0;
 815	}
 816
 817no_rx_data:
 818	if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
 819		trf7970a_send_upstream(trf);
 820		return;
 821	}
 822
 823	dev_dbg(trf->dev, "Setting timeout for %d ms\n",
 824			TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
 825
 826	schedule_delayed_work(&trf->timeout_work,
 827			msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
 828}
 829
 830static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 831{
 832	struct trf7970a *trf = dev_id;
 833	int ret;
 834	u8 status, fifo_bytes, iso_ctrl;
 835
 836	mutex_lock(&trf->lock);
 837
 838	if (trf->state == TRF7970A_ST_RF_OFF) {
 839		mutex_unlock(&trf->lock);
 840		return IRQ_NONE;
 841	}
 842
 843	ret = trf7970a_read_irqstatus(trf, &status);
 844	if (ret) {
 845		mutex_unlock(&trf->lock);
 846		return IRQ_NONE;
 847	}
 848
 849	dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
 850			status);
 851
 852	if (!status) {
 853		mutex_unlock(&trf->lock);
 854		return IRQ_NONE;
 855	}
 856
 857	switch (trf->state) {
 858	case TRF7970A_ST_IDLE:
 859	case TRF7970A_ST_IDLE_RX_BLOCKED:
 860		/* If initiator and getting interrupts caused by RF noise,
 861		 * turn off the receiver to avoid unnecessary interrupts.
 862		 * It will be turned back on in trf7970a_send_cmd() when
 863		 * the next command is issued.
 864		 */
 865		if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
 866			trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
 867			trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
 868		}
 869
 870		trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 871		break;
 872	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
 873		if (status & TRF7970A_IRQ_STATUS_TX) {
 874			trf->ignore_timeout =
 875				!cancel_delayed_work(&trf->timeout_work);
 876			trf7970a_fill_fifo(trf);
 877		} else {
 878			trf7970a_send_err_upstream(trf, -EIO);
 879		}
 880		break;
 881	case TRF7970A_ST_WAIT_FOR_RX_DATA:
 882	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
 883		if (status & TRF7970A_IRQ_STATUS_SRX) {
 884			trf->ignore_timeout =
 885				!cancel_delayed_work(&trf->timeout_work);
 886			trf7970a_drain_fifo(trf, status);
 887		} else if (status & TRF7970A_IRQ_STATUS_FIFO) {
 888			ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
 889					&fifo_bytes);
 890
 891			fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 892
 893			if (ret)
 894				trf7970a_send_err_upstream(trf, ret);
 895			else if (!fifo_bytes)
 896				trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 897		} else if ((status == TRF7970A_IRQ_STATUS_TX) ||
 898				(!trf->is_initiator &&
 899				 (status == (TRF7970A_IRQ_STATUS_TX |
 900					     TRF7970A_IRQ_STATUS_NFC_RF)))) {
 901			trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 902
 903			if (!trf->timeout) {
 904				trf->ignore_timeout = !cancel_delayed_work(
 905						&trf->timeout_work);
 906				trf->rx_skb = ERR_PTR(0);
 907				trf7970a_send_upstream(trf);
 908				break;
 909			}
 910
 911			if (trf->is_initiator)
 912				break;
 913
 914			iso_ctrl = trf->iso_ctrl;
 915
 916			switch (trf->framing) {
 917			case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
 918				trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
 919				iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
 920				trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 921				break;
 922			case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
 923				trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
 924				iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
 925				trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 926				break;
 927			case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
 928				ret = trf7970a_write(trf,
 929					TRF7970A_SPECIAL_FCN_REG1,
 930					TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
 931				if (ret)
 932					goto err_unlock_exit;
 933
 934				trf->special_fcn_reg1 =
 935					TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
 936				break;
 937			default:
 938				break;
 939			}
 940
 941			if (iso_ctrl != trf->iso_ctrl) {
 942				ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
 943						iso_ctrl);
 944				if (ret)
 945					goto err_unlock_exit;
 946
 947				trf->iso_ctrl = iso_ctrl;
 948			}
 949		} else {
 950			trf7970a_send_err_upstream(trf, -EIO);
 951		}
 952		break;
 953	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
 954		if (status != TRF7970A_IRQ_STATUS_TX)
 955			trf7970a_send_err_upstream(trf, -EIO);
 956		break;
 957	case TRF7970A_ST_LISTENING:
 958		if (status & TRF7970A_IRQ_STATUS_SRX) {
 959			trf->ignore_timeout =
 960				!cancel_delayed_work(&trf->timeout_work);
 961			trf7970a_drain_fifo(trf, status);
 962		} else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 963			trf7970a_send_err_upstream(trf, -EIO);
 964		}
 965		break;
 966	case TRF7970A_ST_LISTENING_MD:
 967		if (status & TRF7970A_IRQ_STATUS_SRX) {
 968			trf->ignore_timeout =
 969				!cancel_delayed_work(&trf->timeout_work);
 970
 971			ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
 972			if (ret) {
 973				trf7970a_send_err_upstream(trf, ret);
 974			} else {
 975				trf->state = TRF7970A_ST_LISTENING;
 976				trf7970a_drain_fifo(trf, status);
 977			}
 978		} else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 979			trf7970a_send_err_upstream(trf, -EIO);
 980		}
 981		break;
 982	default:
 983		dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
 984				__func__, trf->state);
 985	}
 986
 987err_unlock_exit:
 988	mutex_unlock(&trf->lock);
 989	return IRQ_HANDLED;
 990}
 991
 992static void trf7970a_issue_eof(struct trf7970a *trf)
 993{
 994	int ret;
 995
 996	dev_dbg(trf->dev, "Issuing EOF\n");
 997
 998	ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 999	if (ret)
1000		trf7970a_send_err_upstream(trf, ret);
1001
1002	ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
1003	if (ret)
1004		trf7970a_send_err_upstream(trf, ret);
1005
1006	trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
1007
1008	dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
1009			trf->timeout, trf->state);
1010
1011	schedule_delayed_work(&trf->timeout_work,
1012			msecs_to_jiffies(trf->timeout));
1013}
1014
1015static void trf7970a_timeout_work_handler(struct work_struct *work)
1016{
1017	struct trf7970a *trf = container_of(work, struct trf7970a,
1018			timeout_work.work);
1019
1020	dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1021			trf->state, trf->ignore_timeout);
1022
1023	mutex_lock(&trf->lock);
1024
1025	if (trf->ignore_timeout)
1026		trf->ignore_timeout = false;
1027	else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1028		trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1029	else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1030		trf7970a_issue_eof(trf);
1031	else
1032		trf7970a_send_err_upstream(trf, -ETIMEDOUT);
1033
1034	mutex_unlock(&trf->lock);
1035}
1036
1037static int trf7970a_init(struct trf7970a *trf)
1038{
1039	int ret;
1040
1041	dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1042
1043	ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1044	if (ret)
1045		goto err_out;
1046
1047	ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1048	if (ret)
1049		goto err_out;
1050
 
 
 
 
 
1051	ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1052	if (ret)
1053		goto err_out;
1054
1055	usleep_range(1000, 2000);
1056
1057	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1058
1059	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
 
1060	if (ret)
1061		goto err_out;
1062
1063	trf->modulator_sys_clk_ctrl = 0;
1064
1065	ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1066			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1067			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1068	if (ret)
1069		goto err_out;
1070
1071	ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1072	if (ret)
1073		goto err_out;
1074
1075	trf->special_fcn_reg1 = 0;
1076
1077	trf->iso_ctrl = 0xff;
1078	return 0;
1079
1080err_out:
1081	dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1082	return ret;
1083}
1084
1085static void trf7970a_switch_rf_off(struct trf7970a *trf)
1086{
1087	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1088			(trf->state == TRF7970A_ST_RF_OFF))
1089		return;
1090
1091	dev_dbg(trf->dev, "Switching rf off\n");
1092
1093	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1094
1095	trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1096
1097	trf->aborting = false;
1098	trf->state = TRF7970A_ST_RF_OFF;
1099
1100	pm_runtime_mark_last_busy(trf->dev);
1101	pm_runtime_put_autosuspend(trf->dev);
1102}
1103
1104static int trf7970a_switch_rf_on(struct trf7970a *trf)
1105{
1106	int ret;
1107
1108	dev_dbg(trf->dev, "Switching rf on\n");
1109
1110	pm_runtime_get_sync(trf->dev);
1111
1112	if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1113		dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1114				trf->state);
1115		return -EINVAL;
1116	}
1117
1118	ret = trf7970a_init(trf);
1119	if (ret) {
1120		dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1121		return ret;
1122	}
1123
1124	trf->state = TRF7970A_ST_IDLE;
1125
1126	return 0;
1127}
1128
1129static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1130{
1131	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1132	int ret = 0;
1133
1134	dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1135
1136	mutex_lock(&trf->lock);
1137
1138	if (on) {
1139		switch (trf->state) {
1140		case TRF7970A_ST_PWR_OFF:
1141		case TRF7970A_ST_RF_OFF:
1142			ret = trf7970a_switch_rf_on(trf);
1143			break;
1144		case TRF7970A_ST_IDLE:
1145		case TRF7970A_ST_IDLE_RX_BLOCKED:
1146			break;
1147		default:
1148			dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1149					__func__, trf->state, on);
1150			trf7970a_switch_rf_off(trf);
1151			ret = -EINVAL;
1152		}
1153	} else {
1154		switch (trf->state) {
1155		case TRF7970A_ST_PWR_OFF:
1156		case TRF7970A_ST_RF_OFF:
1157			break;
1158		default:
1159			dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1160					__func__, trf->state, on);
1161			ret = -EINVAL;
1162			/* FALLTHROUGH */
1163		case TRF7970A_ST_IDLE:
1164		case TRF7970A_ST_IDLE_RX_BLOCKED:
1165		case TRF7970A_ST_WAIT_FOR_RX_DATA:
1166		case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1167			trf7970a_switch_rf_off(trf);
1168		}
1169	}
1170
1171	mutex_unlock(&trf->lock);
1172	return ret;
1173}
1174
1175static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1176{
1177	int ret = 0;
1178
1179	dev_dbg(trf->dev, "rf technology: %d\n", tech);
1180
1181	switch (tech) {
1182	case NFC_DIGITAL_RF_TECH_106A:
1183		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1184		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
 
 
1185		trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1186		break;
1187	case NFC_DIGITAL_RF_TECH_106B:
1188		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1189		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
 
 
1190		trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1191		break;
1192	case NFC_DIGITAL_RF_TECH_212F:
1193		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1194		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
 
 
1195		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1196		break;
1197	case NFC_DIGITAL_RF_TECH_424F:
1198		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1199		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
 
 
1200		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1201		break;
1202	case NFC_DIGITAL_RF_TECH_ISO15693:
1203		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1204		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
 
 
1205		trf->guard_time = TRF7970A_GUARD_TIME_15693;
1206		break;
1207	default:
1208		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1209		return -EINVAL;
1210	}
1211
1212	trf->technology = tech;
1213
1214	/* If in initiator mode and not changing the RF tech due to a
1215	 * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1216	 * trf7970a_init()), clear the NFC Target Detection Level register
1217	 * due to erratum.
1218	 */
1219	if (trf->iso_ctrl == 0xff)
1220		ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1221
1222	return ret;
1223}
1224
1225static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1226{
1227	int ret;
1228	u8 rssi;
1229
1230	ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1231			trf->chip_status_ctrl | TRF7970A_CHIP_STATUS_REC_ON);
 
1232	if (ret)
1233		return ret;
1234
1235	ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1236	if (ret)
1237		return ret;
1238
1239	usleep_range(50, 60);
1240
1241	ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1242	if (ret)
1243		return ret;
1244
1245	ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1246			trf->chip_status_ctrl);
1247	if (ret)
1248		return ret;
1249
1250	if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1251		*is_rf_field = true;
1252	else
1253		*is_rf_field = false;
1254
1255	return 0;
1256}
1257
1258static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1259{
1260	u8 iso_ctrl = trf->iso_ctrl_tech;
1261	bool is_rf_field = false;
1262	int ret;
1263
1264	dev_dbg(trf->dev, "framing: %d\n", framing);
1265
1266	switch (framing) {
1267	case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1268	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1269		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1270		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1271		break;
1272	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1273	case NFC_DIGITAL_FRAMING_NFCA_T4T:
1274	case NFC_DIGITAL_FRAMING_NFCB:
1275	case NFC_DIGITAL_FRAMING_NFCB_T4T:
1276	case NFC_DIGITAL_FRAMING_NFCF:
1277	case NFC_DIGITAL_FRAMING_NFCF_T3T:
1278	case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1279	case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1280	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1281	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1282		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1283		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1284		break;
1285	case NFC_DIGITAL_FRAMING_NFCA_T2T:
1286		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1287		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1288		break;
1289	default:
1290		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1291		return -EINVAL;
1292	}
1293
1294	trf->framing = framing;
1295
1296	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1297		ret = trf7970a_is_rf_field(trf, &is_rf_field);
1298		if (ret)
1299			return ret;
1300
1301		if (is_rf_field)
1302			return -EBUSY;
1303	}
1304
1305	if (iso_ctrl != trf->iso_ctrl) {
1306		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1307		if (ret)
1308			return ret;
1309
1310		trf->iso_ctrl = iso_ctrl;
1311
1312		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1313				trf->modulator_sys_clk_ctrl);
1314		if (ret)
1315			return ret;
1316	}
1317
1318	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1319		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1320				trf->chip_status_ctrl |
1321					TRF7970A_CHIP_STATUS_RF_ON);
1322		if (ret)
1323			return ret;
1324
1325		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1326
1327		usleep_range(trf->guard_time, trf->guard_time + 1000);
1328	}
1329
1330	return 0;
1331}
1332
1333static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1334		int param)
1335{
1336	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1337	int ret;
1338
1339	dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1340
1341	mutex_lock(&trf->lock);
1342
1343	trf->is_initiator = true;
1344
1345	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1346			(trf->state == TRF7970A_ST_RF_OFF)) {
1347		ret = trf7970a_switch_rf_on(trf);
1348		if (ret)
1349			goto err_unlock;
1350	}
1351
1352	switch (type) {
1353	case NFC_DIGITAL_CONFIG_RF_TECH:
1354		ret = trf7970a_in_config_rf_tech(trf, param);
1355		break;
1356	case NFC_DIGITAL_CONFIG_FRAMING:
1357		ret = trf7970a_in_config_framing(trf, param);
1358		break;
1359	default:
1360		dev_dbg(trf->dev, "Unknown type: %d\n", type);
1361		ret = -EINVAL;
1362	}
1363
1364err_unlock:
1365	mutex_unlock(&trf->lock);
1366	return ret;
1367}
1368
1369static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1370{
1371	switch (cmd) {
1372	case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1373	case ISO15693_CMD_LOCK_BLOCK:
1374	case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1375	case ISO15693_CMD_WRITE_AFI:
1376	case ISO15693_CMD_LOCK_AFI:
1377	case ISO15693_CMD_WRITE_DSFID:
1378	case ISO15693_CMD_LOCK_DSFID:
1379		return 1;
1380		break;
1381	default:
1382		return 0;
1383	}
1384}
1385
1386static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
 
1387{
1388	u8 *req = skb->data;
1389	u8 special_fcn_reg1, iso_ctrl;
1390	int ret;
1391
1392	trf->issue_eof = false;
1393
1394	/* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1395	 * special functions register 1 is cleared; otherwise, its a write or
1396	 * sector select command and '4_bit_RX' must be set.
1397	 *
1398	 * When issuing an ISO 15693 command, inspect the flags byte to see
1399	 * what speed to use.  Also, remember if the OPTION flag is set on
1400	 * a Type 5 write or lock command so the driver will know that it
1401	 * has to send an EOF in order to get a response.
1402	 */
1403	if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1404			(trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1405		if (req[0] == NFC_T2T_CMD_READ)
1406			special_fcn_reg1 = 0;
1407		else
1408			special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1409
1410		if (special_fcn_reg1 != trf->special_fcn_reg1) {
1411			ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1412					special_fcn_reg1);
1413			if (ret)
1414				return ret;
1415
1416			trf->special_fcn_reg1 = special_fcn_reg1;
1417		}
1418	} else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1419		iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1420
1421		switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1422		case 0x00:
1423			iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1424			break;
1425		case ISO15693_REQ_FLAG_SUB_CARRIER:
1426			iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1427			break;
1428		case ISO15693_REQ_FLAG_DATA_RATE:
1429			iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1430			break;
1431		case (ISO15693_REQ_FLAG_SUB_CARRIER |
1432				ISO15693_REQ_FLAG_DATA_RATE):
1433			iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1434			break;
1435		}
1436
1437		if (iso_ctrl != trf->iso_ctrl) {
1438			ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1439			if (ret)
1440				return ret;
1441
1442			trf->iso_ctrl = iso_ctrl;
1443		}
1444
1445		if (trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) {
1446			if (trf7970a_is_iso15693_write_or_lock(req[1]) &&
1447					(req[0] & ISO15693_REQ_FLAG_OPTION))
1448				trf->issue_eof = true;
1449			else if ((trf->quirks &
1450					TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE) &&
1451				 (req[1] == ISO15693_CMD_READ_MULTIPLE_BLOCK))
1452				trf->adjust_resp_len = true;
1453		}
1454	}
1455
1456	return 0;
1457}
1458
1459static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1460		struct sk_buff *skb, u16 timeout,
1461		nfc_digital_cmd_complete_t cb, void *arg)
1462{
1463	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1464	u8 prefix[5];
1465	unsigned int len;
1466	int ret;
1467	u8 status;
1468
1469	dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1470			trf->state, timeout, skb->len);
1471
1472	if (skb->len > TRF7970A_TX_MAX)
1473		return -EINVAL;
1474
1475	mutex_lock(&trf->lock);
1476
1477	if ((trf->state != TRF7970A_ST_IDLE) &&
1478			(trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1479		dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1480				trf->state);
1481		ret = -EIO;
1482		goto out_err;
1483	}
1484
1485	if (trf->aborting) {
1486		dev_dbg(trf->dev, "Abort process complete\n");
1487		trf->aborting = false;
1488		ret = -ECANCELED;
1489		goto out_err;
1490	}
1491
1492	if (timeout) {
1493		trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1494				GFP_KERNEL);
1495		if (!trf->rx_skb) {
1496			dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1497			ret = -ENOMEM;
1498			goto out_err;
1499		}
1500	}
1501
1502	if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1503		ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1504		if (ret)
1505			goto out_err;
1506
1507		trf->state = TRF7970A_ST_IDLE;
1508	}
1509
1510	if (trf->is_initiator) {
1511		ret = trf7970a_per_cmd_config(trf, skb);
1512		if (ret)
1513			goto out_err;
1514	}
1515
1516	trf->ddev = ddev;
1517	trf->tx_skb = skb;
1518	trf->cb = cb;
1519	trf->cb_arg = arg;
1520	trf->timeout = timeout;
1521	trf->ignore_timeout = false;
1522
1523	len = skb->len;
1524
1525	/* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1526	 * on what the current framing is, the address of the TX length byte 1
1527	 * register (0x1d), and the 2 byte length of the data to be transmitted.
1528	 * That totals 5 bytes.
1529	 */
1530	prefix[0] = TRF7970A_CMD_BIT_CTRL |
1531			TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1532	prefix[1] = TRF7970A_CMD_BIT_CTRL |
1533			TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1534	prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1535
1536	if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1537		prefix[3] = 0x00;
1538		prefix[4] = 0x0f; /* 7 bits */
1539	} else {
1540		prefix[3] = (len & 0xf00) >> 4;
1541		prefix[3] |= ((len & 0xf0) >> 4);
1542		prefix[4] = ((len & 0x0f) << 4);
1543	}
1544
1545	len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1546
1547	/* Clear possible spurious interrupt */
1548	ret = trf7970a_read_irqstatus(trf, &status);
1549	if (ret)
1550		goto out_err;
1551
1552	ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1553	if (ret) {
1554		kfree_skb(trf->rx_skb);
1555		trf->rx_skb = NULL;
1556	}
1557
1558out_err:
1559	mutex_unlock(&trf->lock);
1560	return ret;
1561}
1562
1563static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1564{
1565	int ret = 0;
1566
1567	dev_dbg(trf->dev, "rf technology: %d\n", tech);
1568
1569	switch (tech) {
1570	case NFC_DIGITAL_RF_TECH_106A:
1571		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1572			TRF7970A_ISO_CTRL_NFC_CE |
1573			TRF7970A_ISO_CTRL_NFC_CE_14443A;
1574		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
 
1575		break;
1576	case NFC_DIGITAL_RF_TECH_212F:
1577		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1578			TRF7970A_ISO_CTRL_NFC_NFCF_212;
1579		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
 
 
1580		break;
1581	case NFC_DIGITAL_RF_TECH_424F:
1582		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1583			TRF7970A_ISO_CTRL_NFC_NFCF_424;
1584		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
 
 
1585		break;
1586	default:
1587		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1588		return -EINVAL;
1589	}
1590
1591	trf->technology = tech;
1592
1593	/* Normally we write the ISO_CTRL register in
1594	 * trf7970a_tg_config_framing() because the framing can change
1595	 * the value written.  However, when sending a PSL RES,
1596	 * digital_tg_send_psl_res_complete() doesn't call
1597	 * trf7970a_tg_config_framing() so we must write the register
1598	 * here.
1599	 */
1600	if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1601			(trf->iso_ctrl_tech != trf->iso_ctrl)) {
1602		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1603				trf->iso_ctrl_tech);
1604
1605		trf->iso_ctrl = trf->iso_ctrl_tech;
1606	}
1607
1608	return ret;
1609}
1610
1611/* Since this is a target routine, several of the framing calls are
1612 * made between receiving the request and sending the response so they
1613 * should take effect until after the response is sent.  This is accomplished
1614 * by skipping the ISO_CTRL register write here and doing it in the interrupt
1615 * handler.
1616 */
1617static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1618{
1619	u8 iso_ctrl = trf->iso_ctrl_tech;
1620	int ret;
1621
1622	dev_dbg(trf->dev, "framing: %d\n", framing);
1623
1624	switch (framing) {
1625	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1626		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1627		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1628		break;
1629	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1630	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1631	case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1632		/* These ones are applied in the interrupt handler */
1633		iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1634		break;
1635	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1636		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1637		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1638		break;
1639	case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1640		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1641		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1642		break;
1643	default:
1644		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1645		return -EINVAL;
1646	}
1647
1648	trf->framing = framing;
1649
1650	if (iso_ctrl != trf->iso_ctrl) {
1651		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1652		if (ret)
1653			return ret;
1654
1655		trf->iso_ctrl = iso_ctrl;
1656
1657		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1658				trf->modulator_sys_clk_ctrl);
1659		if (ret)
1660			return ret;
1661	}
1662
1663	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1664		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1665				trf->chip_status_ctrl |
1666					TRF7970A_CHIP_STATUS_RF_ON);
1667		if (ret)
1668			return ret;
1669
1670		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1671	}
1672
1673	return 0;
1674}
1675
1676static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1677		int param)
1678{
1679	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1680	int ret;
1681
1682	dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1683
1684	mutex_lock(&trf->lock);
1685
1686	trf->is_initiator = false;
1687
1688	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1689			(trf->state == TRF7970A_ST_RF_OFF)) {
1690		ret = trf7970a_switch_rf_on(trf);
1691		if (ret)
1692			goto err_unlock;
1693	}
1694
1695	switch (type) {
1696	case NFC_DIGITAL_CONFIG_RF_TECH:
1697		ret = trf7970a_tg_config_rf_tech(trf, param);
1698		break;
1699	case NFC_DIGITAL_CONFIG_FRAMING:
1700		ret = trf7970a_tg_config_framing(trf, param);
1701		break;
1702	default:
1703		dev_dbg(trf->dev, "Unknown type: %d\n", type);
1704		ret = -EINVAL;
1705	}
1706
1707err_unlock:
1708	mutex_unlock(&trf->lock);
1709	return ret;
1710}
1711
1712static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1713		nfc_digital_cmd_complete_t cb, void *arg, bool mode_detect)
 
1714{
1715	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1716	int ret;
1717
1718	mutex_lock(&trf->lock);
1719
1720	if ((trf->state != TRF7970A_ST_IDLE) &&
1721			(trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1722		dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1723				trf->state);
1724		ret = -EIO;
1725		goto out_err;
1726	}
1727
1728	if (trf->aborting) {
1729		dev_dbg(trf->dev, "Abort process complete\n");
1730		trf->aborting = false;
1731		ret = -ECANCELED;
1732		goto out_err;
1733	}
1734
1735	trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1736			GFP_KERNEL);
1737	if (!trf->rx_skb) {
1738		dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1739		ret = -ENOMEM;
1740		goto out_err;
1741	}
1742
1743	ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1744			TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1745			TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1746			TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1747			TRF7970A_RX_SPECIAL_SETTINGS_C212);
1748	if (ret)
1749		goto out_err;
1750
1751	ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1752			TRF7970A_REG_IO_CTRL_VRS(0x1));
1753	if (ret)
1754		goto out_err;
1755
1756	ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1757			TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1758	if (ret)
1759		goto out_err;
1760
1761	ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1762			TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1763	if (ret)
1764		goto out_err;
1765
1766	trf->ddev = ddev;
1767	trf->cb = cb;
1768	trf->cb_arg = arg;
1769	trf->timeout = timeout;
1770	trf->ignore_timeout = false;
1771
1772	ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1773	if (ret)
1774		goto out_err;
1775
1776	trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1777				   TRF7970A_ST_LISTENING;
1778
1779	schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1780
1781out_err:
1782	mutex_unlock(&trf->lock);
1783	return ret;
1784}
1785
1786static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1787		nfc_digital_cmd_complete_t cb, void *arg)
1788{
1789	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1790
1791	dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1792			trf->state, timeout);
1793
1794	return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1795}
1796
1797static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1798		u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
 
1799{
1800	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1801	int ret;
1802
1803	dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1804			trf->state, timeout);
1805
1806	ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1807			NFC_DIGITAL_RF_TECH_106A);
1808	if (ret)
1809		return ret;
1810
1811	ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1812			NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1813	if (ret)
1814		return ret;
1815
1816	return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1817}
1818
1819static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1820{
1821	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1822
1823	dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1824			trf->state, trf->md_rf_tech);
1825
1826	*rf_tech = trf->md_rf_tech;
1827
1828	return 0;
1829}
1830
1831static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1832{
1833	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1834
1835	dev_dbg(trf->dev, "Abort process initiated\n");
1836
1837	mutex_lock(&trf->lock);
1838
1839	switch (trf->state) {
1840	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1841	case TRF7970A_ST_WAIT_FOR_RX_DATA:
1842	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1843	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1844		trf->aborting = true;
1845		break;
1846	case TRF7970A_ST_LISTENING:
1847		trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1848		trf7970a_send_err_upstream(trf, -ECANCELED);
1849		dev_dbg(trf->dev, "Abort process complete\n");
1850		break;
1851	default:
1852		break;
1853	}
1854
1855	mutex_unlock(&trf->lock);
1856}
1857
1858static struct nfc_digital_ops trf7970a_nfc_ops = {
1859	.in_configure_hw	= trf7970a_in_configure_hw,
1860	.in_send_cmd		= trf7970a_send_cmd,
1861	.tg_configure_hw	= trf7970a_tg_configure_hw,
1862	.tg_send_cmd		= trf7970a_send_cmd,
1863	.tg_listen		= trf7970a_tg_listen,
1864	.tg_listen_md		= trf7970a_tg_listen_md,
1865	.tg_get_rf_tech		= trf7970a_tg_get_rf_tech,
1866	.switch_rf		= trf7970a_switch_rf,
1867	.abort_cmd		= trf7970a_abort_cmd,
1868};
1869
1870static int trf7970a_power_up(struct trf7970a *trf)
1871{
1872	int ret;
1873
1874	dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1875
1876	if (trf->state != TRF7970A_ST_PWR_OFF)
1877		return 0;
1878
1879	ret = regulator_enable(trf->regulator);
1880	if (ret) {
1881		dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1882		return ret;
1883	}
1884
1885	usleep_range(5000, 6000);
1886
1887	if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1888		gpio_set_value(trf->en2_gpio, 1);
 
1889		usleep_range(1000, 2000);
1890	}
1891
1892	gpio_set_value(trf->en_gpio, 1);
1893
1894	usleep_range(20000, 21000);
1895
1896	trf->state = TRF7970A_ST_RF_OFF;
1897
1898	return 0;
1899}
1900
1901static int trf7970a_power_down(struct trf7970a *trf)
1902{
1903	int ret;
1904
1905	dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1906
1907	if (trf->state == TRF7970A_ST_PWR_OFF)
1908		return 0;
1909
1910	if (trf->state != TRF7970A_ST_RF_OFF) {
1911		dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1912				trf->state);
1913		return -EBUSY;
1914	}
1915
1916	gpio_set_value(trf->en_gpio, 0);
1917	gpio_set_value(trf->en2_gpio, 0);
 
 
1918
1919	ret = regulator_disable(trf->regulator);
1920	if (ret)
1921		dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1922				ret);
1923
1924	trf->state = TRF7970A_ST_PWR_OFF;
1925
1926	return ret;
1927}
1928
1929static int trf7970a_startup(struct trf7970a *trf)
1930{
1931	int ret;
1932
1933	ret = trf7970a_power_up(trf);
1934	if (ret)
1935		return ret;
1936
1937	pm_runtime_set_active(trf->dev);
1938	pm_runtime_enable(trf->dev);
1939	pm_runtime_mark_last_busy(trf->dev);
1940
1941	return 0;
1942}
1943
1944static void trf7970a_shutdown(struct trf7970a *trf)
1945{
1946	switch (trf->state) {
1947	case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1948	case TRF7970A_ST_WAIT_FOR_RX_DATA:
1949	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1950	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1951	case TRF7970A_ST_LISTENING:
1952		trf7970a_send_err_upstream(trf, -ECANCELED);
1953		/* FALLTHROUGH */
1954	case TRF7970A_ST_IDLE:
1955	case TRF7970A_ST_IDLE_RX_BLOCKED:
1956		trf7970a_switch_rf_off(trf);
1957		break;
1958	default:
1959		break;
1960	}
1961
1962	pm_runtime_disable(trf->dev);
1963	pm_runtime_set_suspended(trf->dev);
1964
1965	trf7970a_power_down(trf);
1966}
1967
1968static int trf7970a_get_autosuspend_delay(struct device_node *np)
1969{
1970	int autosuspend_delay, ret;
1971
1972	ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
1973	if (ret)
1974		autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
1975
1976	return autosuspend_delay;
1977}
1978
1979static int trf7970a_get_vin_voltage_override(struct device_node *np,
1980		u32 *vin_uvolts)
1981{
1982	return of_property_read_u32(np, "vin-voltage-override", vin_uvolts);
1983}
1984
1985static int trf7970a_probe(struct spi_device *spi)
1986{
1987	struct device_node *np = spi->dev.of_node;
1988	struct trf7970a *trf;
1989	int uvolts, autosuspend_delay, ret;
 
1990
1991	if (!np) {
1992		dev_err(&spi->dev, "No Device Tree entry\n");
1993		return -EINVAL;
1994	}
1995
1996	trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
1997	if (!trf)
1998		return -ENOMEM;
1999
2000	trf->state = TRF7970A_ST_PWR_OFF;
2001	trf->dev = &spi->dev;
2002	trf->spi = spi;
2003
2004	spi->mode = SPI_MODE_1;
2005	spi->bits_per_word = 8;
2006
2007	ret = spi_setup(spi);
2008	if (ret < 0) {
2009		dev_err(trf->dev, "Can't set up SPI Communication\n");
2010		return ret;
2011	}
2012
2013	if (of_property_read_bool(np, "t5t-rmb-extra-byte-quirk"))
2014		trf->quirks |= TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE;
2015
2016	if (of_property_read_bool(np, "irq-status-read-quirk"))
2017		trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
2018
2019	/* There are two enable pins - both must be present */
2020	trf->en_gpio = of_get_named_gpio(np, "ti,enable-gpios", 0);
2021	if (!gpio_is_valid(trf->en_gpio)) {
 
2022		dev_err(trf->dev, "No EN GPIO property\n");
2023		return trf->en_gpio;
2024	}
2025
2026	ret = devm_gpio_request_one(trf->dev, trf->en_gpio,
2027			GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN");
2028	if (ret) {
2029		dev_err(trf->dev, "Can't request EN GPIO: %d\n", ret);
2030		return ret;
 
 
 
 
 
2031	}
2032
2033	trf->en2_gpio = of_get_named_gpio(np, "ti,enable-gpios", 1);
2034	if (!gpio_is_valid(trf->en2_gpio)) {
2035		dev_err(trf->dev, "No EN2 GPIO property\n");
2036		return trf->en2_gpio;
 
 
2037	}
2038
2039	ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
2040			GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN2");
2041	if (ret) {
2042		dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
2043		return ret;
2044	}
2045
2046	if (of_property_read_bool(np, "en2-rf-quirk"))
2047		trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2048
2049	ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2050			trf7970a_irq, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2051			"trf7970a", trf);
 
2052	if (ret) {
2053		dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2054		return ret;
2055	}
2056
2057	mutex_init(&trf->lock);
2058	INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2059
2060	trf->regulator = devm_regulator_get(&spi->dev, "vin");
2061	if (IS_ERR(trf->regulator)) {
2062		ret = PTR_ERR(trf->regulator);
2063		dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2064		goto err_destroy_lock;
2065	}
2066
2067	ret = regulator_enable(trf->regulator);
2068	if (ret) {
2069		dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2070		goto err_destroy_lock;
2071	}
2072
2073	ret = trf7970a_get_vin_voltage_override(np, &uvolts);
2074	if (ret)
2075		uvolts = regulator_get_voltage(trf->regulator);
2076
2077	if (uvolts > 4000000)
2078		trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2079
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2080	trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2081			TRF7970A_SUPPORTED_PROTOCOLS,
2082			NFC_DIGITAL_DRV_CAPS_IN_CRC |
2083				NFC_DIGITAL_DRV_CAPS_TG_CRC, 0, 0);
 
2084	if (!trf->ddev) {
2085		dev_err(trf->dev, "Can't allocate NFC digital device\n");
2086		ret = -ENOMEM;
2087		goto err_disable_regulator;
2088	}
2089
2090	nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2091	nfc_digital_set_drvdata(trf->ddev, trf);
2092	spi_set_drvdata(spi, trf);
2093
2094	autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2095
2096	pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2097	pm_runtime_use_autosuspend(trf->dev);
2098
2099	ret = trf7970a_startup(trf);
2100	if (ret)
2101		goto err_free_ddev;
2102
2103	ret = nfc_digital_register_device(trf->ddev);
2104	if (ret) {
2105		dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2106				ret);
2107		goto err_shutdown;
2108	}
2109
2110	return 0;
2111
2112err_shutdown:
2113	trf7970a_shutdown(trf);
2114err_free_ddev:
2115	nfc_digital_free_device(trf->ddev);
2116err_disable_regulator:
2117	regulator_disable(trf->regulator);
2118err_destroy_lock:
2119	mutex_destroy(&trf->lock);
2120	return ret;
2121}
2122
2123static int trf7970a_remove(struct spi_device *spi)
2124{
2125	struct trf7970a *trf = spi_get_drvdata(spi);
2126
2127	mutex_lock(&trf->lock);
2128
2129	trf7970a_shutdown(trf);
2130
2131	mutex_unlock(&trf->lock);
2132
2133	nfc_digital_unregister_device(trf->ddev);
2134	nfc_digital_free_device(trf->ddev);
2135
2136	regulator_disable(trf->regulator);
2137
2138	mutex_destroy(&trf->lock);
2139
2140	return 0;
2141}
2142
2143#ifdef CONFIG_PM_SLEEP
2144static int trf7970a_suspend(struct device *dev)
2145{
2146	struct spi_device *spi = to_spi_device(dev);
2147	struct trf7970a *trf = spi_get_drvdata(spi);
2148
2149	dev_dbg(dev, "Suspend\n");
2150
2151	mutex_lock(&trf->lock);
2152
2153	trf7970a_shutdown(trf);
2154
2155	mutex_unlock(&trf->lock);
2156
2157	return 0;
2158}
2159
2160static int trf7970a_resume(struct device *dev)
2161{
2162	struct spi_device *spi = to_spi_device(dev);
2163	struct trf7970a *trf = spi_get_drvdata(spi);
2164	int ret;
2165
2166	dev_dbg(dev, "Resume\n");
2167
2168	mutex_lock(&trf->lock);
2169
2170	ret = trf7970a_startup(trf);
2171
2172	mutex_unlock(&trf->lock);
2173
2174	return ret;
2175}
2176#endif
2177
2178#ifdef CONFIG_PM
2179static int trf7970a_pm_runtime_suspend(struct device *dev)
2180{
2181	struct spi_device *spi = to_spi_device(dev);
2182	struct trf7970a *trf = spi_get_drvdata(spi);
2183	int ret;
2184
2185	dev_dbg(dev, "Runtime suspend\n");
2186
2187	mutex_lock(&trf->lock);
2188
2189	ret = trf7970a_power_down(trf);
2190
2191	mutex_unlock(&trf->lock);
2192
2193	return ret;
2194}
2195
2196static int trf7970a_pm_runtime_resume(struct device *dev)
2197{
2198	struct spi_device *spi = to_spi_device(dev);
2199	struct trf7970a *trf = spi_get_drvdata(spi);
2200	int ret;
2201
2202	dev_dbg(dev, "Runtime resume\n");
2203
2204	ret = trf7970a_power_up(trf);
2205	if (!ret)
2206		pm_runtime_mark_last_busy(dev);
2207
2208	return ret;
2209}
2210#endif
2211
2212static const struct dev_pm_ops trf7970a_pm_ops = {
2213	SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2214	SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2215			trf7970a_pm_runtime_resume, NULL)
2216};
2217
2218static const struct of_device_id trf7970a_of_match[] = {
2219	{ .compatible = "ti,trf7970a", },
2220	{ /* sentinel */ },
2221};
 
2222MODULE_DEVICE_TABLE(of, trf7970a_of_match);
2223
2224static const struct spi_device_id trf7970a_id_table[] = {
2225	{ "trf7970a", 0 },
2226	{ }
2227};
 
2228MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2229
2230static struct spi_driver trf7970a_spi_driver = {
2231	.probe		= trf7970a_probe,
2232	.remove		= trf7970a_remove,
2233	.id_table	= trf7970a_id_table,
2234	.driver		= {
2235		.name	= "trf7970a",
2236		.of_match_table = of_match_ptr(trf7970a_of_match),
2237		.pm	= &trf7970a_pm_ops,
2238	},
2239};
2240
2241module_spi_driver(trf7970a_spi_driver);
2242
2243MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2244MODULE_LICENSE("GPL v2");
2245MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");