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v5.9
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * SH RSPI driver
   4 *
   5 * Copyright (C) 2012, 2013  Renesas Solutions Corp.
   6 * Copyright (C) 2014 Glider bvba
   7 *
   8 * Based on spi-sh.c:
   9 * Copyright (C) 2011 Renesas Solutions Corp.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/kernel.h>
  14#include <linux/sched.h>
  15#include <linux/errno.h>
 
 
  16#include <linux/interrupt.h>
  17#include <linux/platform_device.h>
  18#include <linux/io.h>
  19#include <linux/clk.h>
  20#include <linux/dmaengine.h>
  21#include <linux/dma-mapping.h>
  22#include <linux/of_device.h>
  23#include <linux/pm_runtime.h>
  24#include <linux/sh_dma.h>
  25#include <linux/spi/spi.h>
  26#include <linux/spi/rspi.h>
  27#include <linux/spinlock.h>
  28
  29#define RSPI_SPCR		0x00	/* Control Register */
  30#define RSPI_SSLP		0x01	/* Slave Select Polarity Register */
  31#define RSPI_SPPCR		0x02	/* Pin Control Register */
  32#define RSPI_SPSR		0x03	/* Status Register */
  33#define RSPI_SPDR		0x04	/* Data Register */
  34#define RSPI_SPSCR		0x08	/* Sequence Control Register */
  35#define RSPI_SPSSR		0x09	/* Sequence Status Register */
  36#define RSPI_SPBR		0x0a	/* Bit Rate Register */
  37#define RSPI_SPDCR		0x0b	/* Data Control Register */
  38#define RSPI_SPCKD		0x0c	/* Clock Delay Register */
  39#define RSPI_SSLND		0x0d	/* Slave Select Negation Delay Register */
  40#define RSPI_SPND		0x0e	/* Next-Access Delay Register */
  41#define RSPI_SPCR2		0x0f	/* Control Register 2 (SH only) */
  42#define RSPI_SPCMD0		0x10	/* Command Register 0 */
  43#define RSPI_SPCMD1		0x12	/* Command Register 1 */
  44#define RSPI_SPCMD2		0x14	/* Command Register 2 */
  45#define RSPI_SPCMD3		0x16	/* Command Register 3 */
  46#define RSPI_SPCMD4		0x18	/* Command Register 4 */
  47#define RSPI_SPCMD5		0x1a	/* Command Register 5 */
  48#define RSPI_SPCMD6		0x1c	/* Command Register 6 */
  49#define RSPI_SPCMD7		0x1e	/* Command Register 7 */
  50#define RSPI_SPCMD(i)		(RSPI_SPCMD0 + (i) * 2)
  51#define RSPI_NUM_SPCMD		8
  52#define RSPI_RZ_NUM_SPCMD	4
  53#define QSPI_NUM_SPCMD		4
  54
  55/* RSPI on RZ only */
  56#define RSPI_SPBFCR		0x20	/* Buffer Control Register */
  57#define RSPI_SPBFDR		0x22	/* Buffer Data Count Setting Register */
  58
  59/* QSPI only */
  60#define QSPI_SPBFCR		0x18	/* Buffer Control Register */
  61#define QSPI_SPBDCR		0x1a	/* Buffer Data Count Register */
  62#define QSPI_SPBMUL0		0x1c	/* Transfer Data Length Multiplier Setting Register 0 */
  63#define QSPI_SPBMUL1		0x20	/* Transfer Data Length Multiplier Setting Register 1 */
  64#define QSPI_SPBMUL2		0x24	/* Transfer Data Length Multiplier Setting Register 2 */
  65#define QSPI_SPBMUL3		0x28	/* Transfer Data Length Multiplier Setting Register 3 */
  66#define QSPI_SPBMUL(i)		(QSPI_SPBMUL0 + (i) * 4)
  67
  68/* SPCR - Control Register */
  69#define SPCR_SPRIE		0x80	/* Receive Interrupt Enable */
  70#define SPCR_SPE		0x40	/* Function Enable */
  71#define SPCR_SPTIE		0x20	/* Transmit Interrupt Enable */
  72#define SPCR_SPEIE		0x10	/* Error Interrupt Enable */
  73#define SPCR_MSTR		0x08	/* Master/Slave Mode Select */
  74#define SPCR_MODFEN		0x04	/* Mode Fault Error Detection Enable */
  75/* RSPI on SH only */
  76#define SPCR_TXMD		0x02	/* TX Only Mode (vs. Full Duplex) */
  77#define SPCR_SPMS		0x01	/* 3-wire Mode (vs. 4-wire) */
  78/* QSPI on R-Car Gen2 only */
  79#define SPCR_WSWAP		0x02	/* Word Swap of read-data for DMAC */
  80#define SPCR_BSWAP		0x01	/* Byte Swap of read-data for DMAC */
  81
  82/* SSLP - Slave Select Polarity Register */
  83#define SSLP_SSLP(i)		BIT(i)	/* SSLi Signal Polarity Setting */
  84
  85/* SPPCR - Pin Control Register */
  86#define SPPCR_MOIFE		0x20	/* MOSI Idle Value Fixing Enable */
  87#define SPPCR_MOIFV		0x10	/* MOSI Idle Fixed Value */
  88#define SPPCR_SPOM		0x04
  89#define SPPCR_SPLP2		0x02	/* Loopback Mode 2 (non-inverting) */
  90#define SPPCR_SPLP		0x01	/* Loopback Mode (inverting) */
  91
  92#define SPPCR_IO3FV		0x04	/* Single-/Dual-SPI Mode IO3 Output Fixed Value */
  93#define SPPCR_IO2FV		0x04	/* Single-/Dual-SPI Mode IO2 Output Fixed Value */
  94
  95/* SPSR - Status Register */
  96#define SPSR_SPRF		0x80	/* Receive Buffer Full Flag */
  97#define SPSR_TEND		0x40	/* Transmit End */
  98#define SPSR_SPTEF		0x20	/* Transmit Buffer Empty Flag */
  99#define SPSR_PERF		0x08	/* Parity Error Flag */
 100#define SPSR_MODF		0x04	/* Mode Fault Error Flag */
 101#define SPSR_IDLNF		0x02	/* RSPI Idle Flag */
 102#define SPSR_OVRF		0x01	/* Overrun Error Flag (RSPI only) */
 103
 104/* SPSCR - Sequence Control Register */
 105#define SPSCR_SPSLN_MASK	0x07	/* Sequence Length Specification */
 106
 107/* SPSSR - Sequence Status Register */
 108#define SPSSR_SPECM_MASK	0x70	/* Command Error Mask */
 109#define SPSSR_SPCP_MASK		0x07	/* Command Pointer Mask */
 110
 111/* SPDCR - Data Control Register */
 112#define SPDCR_TXDMY		0x80	/* Dummy Data Transmission Enable */
 113#define SPDCR_SPLW1		0x40	/* Access Width Specification (RZ) */
 114#define SPDCR_SPLW0		0x20	/* Access Width Specification (RZ) */
 115#define SPDCR_SPLLWORD		(SPDCR_SPLW1 | SPDCR_SPLW0)
 116#define SPDCR_SPLWORD		SPDCR_SPLW1
 117#define SPDCR_SPLBYTE		SPDCR_SPLW0
 118#define SPDCR_SPLW		0x20	/* Access Width Specification (SH) */
 119#define SPDCR_SPRDTD		0x10	/* Receive Transmit Data Select (SH) */
 120#define SPDCR_SLSEL1		0x08
 121#define SPDCR_SLSEL0		0x04
 122#define SPDCR_SLSEL_MASK	0x0c	/* SSL1 Output Select (SH) */
 123#define SPDCR_SPFC1		0x02
 124#define SPDCR_SPFC0		0x01
 125#define SPDCR_SPFC_MASK		0x03	/* Frame Count Setting (1-4) (SH) */
 126
 127/* SPCKD - Clock Delay Register */
 128#define SPCKD_SCKDL_MASK	0x07	/* Clock Delay Setting (1-8) */
 
 
 
 129
 130/* SSLND - Slave Select Negation Delay Register */
 131#define SSLND_SLNDL_MASK	0x07	/* SSL Negation Delay Setting (1-8) */
 132
 133/* SPND - Next-Access Delay Register */
 134#define SPND_SPNDL_MASK		0x07	/* Next-Access Delay Setting (1-8) */
 135
 136/* SPCR2 - Control Register 2 */
 137#define SPCR2_PTE		0x08	/* Parity Self-Test Enable */
 138#define SPCR2_SPIE		0x04	/* Idle Interrupt Enable */
 139#define SPCR2_SPOE		0x02	/* Odd Parity Enable (vs. Even) */
 140#define SPCR2_SPPE		0x01	/* Parity Enable */
 141
 142/* SPCMDn - Command Registers */
 143#define SPCMD_SCKDEN		0x8000	/* Clock Delay Setting Enable */
 144#define SPCMD_SLNDEN		0x4000	/* SSL Negation Delay Setting Enable */
 145#define SPCMD_SPNDEN		0x2000	/* Next-Access Delay Enable */
 146#define SPCMD_LSBF		0x1000	/* LSB First */
 147#define SPCMD_SPB_MASK		0x0f00	/* Data Length Setting */
 148#define SPCMD_SPB_8_TO_16(bit)	(((bit - 1) << 8) & SPCMD_SPB_MASK)
 149#define SPCMD_SPB_8BIT		0x0000	/* QSPI only */
 150#define SPCMD_SPB_16BIT		0x0100
 151#define SPCMD_SPB_20BIT		0x0000
 152#define SPCMD_SPB_24BIT		0x0100
 153#define SPCMD_SPB_32BIT		0x0200
 154#define SPCMD_SSLKP		0x0080	/* SSL Signal Level Keeping */
 155#define SPCMD_SPIMOD_MASK	0x0060	/* SPI Operating Mode (QSPI only) */
 156#define SPCMD_SPIMOD1		0x0040
 157#define SPCMD_SPIMOD0		0x0020
 158#define SPCMD_SPIMOD_SINGLE	0
 159#define SPCMD_SPIMOD_DUAL	SPCMD_SPIMOD0
 160#define SPCMD_SPIMOD_QUAD	SPCMD_SPIMOD1
 161#define SPCMD_SPRW		0x0010	/* SPI Read/Write Access (Dual/Quad) */
 162#define SPCMD_SSLA(i)		((i) << 4)	/* SSL Assert Signal Setting */
 163#define SPCMD_BRDV_MASK		0x000c	/* Bit Rate Division Setting */
 164#define SPCMD_CPOL		0x0002	/* Clock Polarity Setting */
 165#define SPCMD_CPHA		0x0001	/* Clock Phase Setting */
 166
 167/* SPBFCR - Buffer Control Register */
 168#define SPBFCR_TXRST		0x80	/* Transmit Buffer Data Reset */
 169#define SPBFCR_RXRST		0x40	/* Receive Buffer Data Reset */
 170#define SPBFCR_TXTRG_MASK	0x30	/* Transmit Buffer Data Triggering Number */
 171#define SPBFCR_RXTRG_MASK	0x07	/* Receive Buffer Data Triggering Number */
 172/* QSPI on R-Car Gen2 */
 173#define SPBFCR_TXTRG_1B		0x00	/* 31 bytes (1 byte available) */
 174#define SPBFCR_TXTRG_32B	0x30	/* 0 byte (32 bytes available) */
 175#define SPBFCR_RXTRG_1B		0x00	/* 1 byte (31 bytes available) */
 176#define SPBFCR_RXTRG_32B	0x07	/* 32 bytes (0 byte available) */
 177
 178#define QSPI_BUFFER_SIZE        32u
 179
 180struct rspi_data {
 181	void __iomem *addr;
 182	u32 speed_hz;
 183	struct spi_controller *ctlr;
 184	struct platform_device *pdev;
 
 185	wait_queue_head_t wait;
 186	spinlock_t lock;		/* Protects RMW-access to RSPI_SSLP */
 187	struct clk *clk;
 188	u16 spcmd;
 189	u8 spsr;
 190	u8 sppcr;
 191	int rx_irq, tx_irq;
 192	const struct spi_ops *ops;
 
 
 
 193
 
 194	unsigned dma_callbacked:1;
 195	unsigned byte_access:1;
 196};
 197
 198static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
 199{
 200	iowrite8(data, rspi->addr + offset);
 201}
 202
 203static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
 204{
 205	iowrite16(data, rspi->addr + offset);
 206}
 207
 208static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
 209{
 210	iowrite32(data, rspi->addr + offset);
 211}
 212
 213static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
 214{
 215	return ioread8(rspi->addr + offset);
 216}
 217
 218static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
 219{
 220	return ioread16(rspi->addr + offset);
 221}
 222
 223static void rspi_write_data(const struct rspi_data *rspi, u16 data)
 224{
 225	if (rspi->byte_access)
 226		rspi_write8(rspi, data, RSPI_SPDR);
 227	else /* 16 bit */
 228		rspi_write16(rspi, data, RSPI_SPDR);
 229}
 230
 231static u16 rspi_read_data(const struct rspi_data *rspi)
 232{
 233	if (rspi->byte_access)
 234		return rspi_read8(rspi, RSPI_SPDR);
 235	else /* 16 bit */
 236		return rspi_read16(rspi, RSPI_SPDR);
 237}
 238
 239/* optional functions */
 240struct spi_ops {
 241	int (*set_config_register)(struct rspi_data *rspi, int access_size);
 242	int (*transfer_one)(struct spi_controller *ctlr,
 243			    struct spi_device *spi, struct spi_transfer *xfer);
 244	u16 extra_mode_bits;
 245	u16 flags;
 246	u16 fifo_size;
 247	u8 num_hw_ss;
 248};
 249
 250/*
 251 * functions for RSPI on legacy SH
 252 */
 253static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
 254{
 255	int spbr;
 256
 257	/* Sets output mode, MOSI signal, and (optionally) loopback */
 258	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
 259
 260	/* Sets transfer bit rate */
 261	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->speed_hz) - 1;
 262	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
 263
 264	/* Disable dummy transmission, set 16-bit word access, 1 frame */
 265	rspi_write8(rspi, 0, RSPI_SPDCR);
 266	rspi->byte_access = 0;
 267
 268	/* Sets RSPCK, SSL, next-access delay value */
 269	rspi_write8(rspi, 0x00, RSPI_SPCKD);
 270	rspi_write8(rspi, 0x00, RSPI_SSLND);
 271	rspi_write8(rspi, 0x00, RSPI_SPND);
 272
 273	/* Sets parity, interrupt mask */
 274	rspi_write8(rspi, 0x00, RSPI_SPCR2);
 
 
 275
 276	/* Resets sequencer */
 277	rspi_write8(rspi, 0, RSPI_SPSCR);
 278	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
 279	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
 280
 281	/* Sets RSPI mode */
 282	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
 
 
 
 283
 284	return 0;
 285}
 286
 287/*
 288 * functions for RSPI on RZ
 289 */
 290static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
 291{
 292	int spbr;
 293	int div = 0;
 294	unsigned long clksrc;
 295
 296	/* Sets output mode, MOSI signal, and (optionally) loopback */
 297	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
 298
 299	clksrc = clk_get_rate(rspi->clk);
 300	while (div < 3) {
 301		if (rspi->speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */
 302			break;
 303		div++;
 304		clksrc /= 2;
 305	}
 306
 307	/* Sets transfer bit rate */
 308	spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1;
 309	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
 310	rspi->spcmd |= div << 2;
 311
 312	/* Disable dummy transmission, set byte access */
 313	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
 314	rspi->byte_access = 1;
 315
 316	/* Sets RSPCK, SSL, next-access delay value */
 317	rspi_write8(rspi, 0x00, RSPI_SPCKD);
 318	rspi_write8(rspi, 0x00, RSPI_SSLND);
 319	rspi_write8(rspi, 0x00, RSPI_SPND);
 320
 321	/* Resets sequencer */
 322	rspi_write8(rspi, 0, RSPI_SPSCR);
 323	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
 324	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
 325
 326	/* Sets RSPI mode */
 327	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
 328
 329	return 0;
 330}
 331
 332/*
 333 * functions for QSPI
 334 */
 335static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
 336{
 337	int spbr;
 
 338
 339	/* Sets output mode, MOSI signal, and (optionally) loopback */
 340	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
 
 
 341
 342	/* Sets transfer bit rate */
 343	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->speed_hz);
 344	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
 345
 346	/* Disable dummy transmission, set byte access */
 347	rspi_write8(rspi, 0, RSPI_SPDCR);
 348	rspi->byte_access = 1;
 349
 350	/* Sets RSPCK, SSL, next-access delay value */
 351	rspi_write8(rspi, 0x00, RSPI_SPCKD);
 352	rspi_write8(rspi, 0x00, RSPI_SSLND);
 353	rspi_write8(rspi, 0x00, RSPI_SPND);
 354
 355	/* Data Length Setting */
 356	if (access_size == 8)
 357		rspi->spcmd |= SPCMD_SPB_8BIT;
 358	else if (access_size == 16)
 359		rspi->spcmd |= SPCMD_SPB_16BIT;
 360	else
 361		rspi->spcmd |= SPCMD_SPB_32BIT;
 362
 363	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
 364
 365	/* Resets transfer data length */
 366	rspi_write32(rspi, 0, QSPI_SPBMUL0);
 367
 368	/* Resets transmit and receive buffer */
 369	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
 370	/* Sets buffer to allow normal operation */
 371	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
 372
 373	/* Resets sequencer */
 374	rspi_write8(rspi, 0, RSPI_SPSCR);
 375	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
 376
 377	/* Sets RSPI mode */
 378	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
 379
 380	return 0;
 381}
 382
 383static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
 
 384{
 385	u8 data;
 
 386
 387	data = rspi_read8(rspi, reg);
 388	data &= ~mask;
 389	data |= (val & mask);
 390	rspi_write8(rspi, data, reg);
 391}
 392
 393static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
 394					  unsigned int len)
 395{
 396	unsigned int n;
 397
 398	n = min(len, QSPI_BUFFER_SIZE);
 
 
 
 
 399
 400	if (len >= QSPI_BUFFER_SIZE) {
 401		/* sets triggering number to 32 bytes */
 402		qspi_update(rspi, SPBFCR_TXTRG_MASK,
 403			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
 404	} else {
 405		/* sets triggering number to 1 byte */
 406		qspi_update(rspi, SPBFCR_TXTRG_MASK,
 407			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
 408	}
 409
 410	return n;
 411}
 412
 413static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
 414{
 415	unsigned int n;
 416
 417	n = min(len, QSPI_BUFFER_SIZE);
 418
 419	if (len >= QSPI_BUFFER_SIZE) {
 420		/* sets triggering number to 32 bytes */
 421		qspi_update(rspi, SPBFCR_RXTRG_MASK,
 422			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
 423	} else {
 424		/* sets triggering number to 1 byte */
 425		qspi_update(rspi, SPBFCR_RXTRG_MASK,
 426			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
 427	}
 428	return n;
 429}
 430
 431static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
 432{
 433	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
 434}
 435
 436static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
 437{
 438	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
 439}
 440
 441static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
 442				   u8 enable_bit)
 
 443{
 444	int ret;
 445
 446	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
 447	if (rspi->spsr & wait_mask)
 448		return 0;
 449
 450	rspi_enable_irq(rspi, enable_bit);
 451	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
 452	if (ret == 0 && !(rspi->spsr & wait_mask))
 453		return -ETIMEDOUT;
 454
 455	return 0;
 456}
 457
 458static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
 
 459{
 460	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
 461}
 462
 463static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
 464{
 465	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
 466}
 467
 468static int rspi_data_out(struct rspi_data *rspi, u8 data)
 469{
 470	int error = rspi_wait_for_tx_empty(rspi);
 471	if (error < 0) {
 472		dev_err(&rspi->ctlr->dev, "transmit timeout\n");
 473		return error;
 474	}
 475	rspi_write_data(rspi, data);
 476	return 0;
 477}
 478
 479static int rspi_data_in(struct rspi_data *rspi)
 480{
 481	int error;
 482	u8 data;
 483
 484	error = rspi_wait_for_rx_full(rspi);
 485	if (error < 0) {
 486		dev_err(&rspi->ctlr->dev, "receive timeout\n");
 487		return error;
 488	}
 489	data = rspi_read_data(rspi);
 490	return data;
 491}
 492
 493static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
 494			     unsigned int n)
 495{
 496	while (n-- > 0) {
 497		if (tx) {
 498			int ret = rspi_data_out(rspi, *tx++);
 499			if (ret < 0)
 500				return ret;
 501		}
 502		if (rx) {
 503			int ret = rspi_data_in(rspi);
 504			if (ret < 0)
 505				return ret;
 506			*rx++ = ret;
 507		}
 508	}
 509
 510	return 0;
 511}
 512
 513static void rspi_dma_complete(void *arg)
 514{
 515	struct rspi_data *rspi = arg;
 
 
 
 
 516
 517	rspi->dma_callbacked = 1;
 518	wake_up_interruptible(&rspi->wait);
 519}
 520
 521static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
 522			     struct sg_table *rx)
 523{
 524	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
 525	u8 irq_mask = 0;
 526	unsigned int other_irq = 0;
 527	dma_cookie_t cookie;
 528	int ret;
 529
 530	/* First prepare and submit the DMA request(s), as this may fail */
 531	if (rx) {
 532		desc_rx = dmaengine_prep_slave_sg(rspi->ctlr->dma_rx, rx->sgl,
 533					rx->nents, DMA_DEV_TO_MEM,
 534					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 535		if (!desc_rx) {
 536			ret = -EAGAIN;
 537			goto no_dma_rx;
 538		}
 539
 540		desc_rx->callback = rspi_dma_complete;
 541		desc_rx->callback_param = rspi;
 542		cookie = dmaengine_submit(desc_rx);
 543		if (dma_submit_error(cookie)) {
 544			ret = cookie;
 545			goto no_dma_rx;
 546		}
 547
 548		irq_mask |= SPCR_SPRIE;
 549	}
 550
 551	if (tx) {
 552		desc_tx = dmaengine_prep_slave_sg(rspi->ctlr->dma_tx, tx->sgl,
 553					tx->nents, DMA_MEM_TO_DEV,
 554					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 555		if (!desc_tx) {
 556			ret = -EAGAIN;
 557			goto no_dma_tx;
 558		}
 559
 560		if (rx) {
 561			/* No callback */
 562			desc_tx->callback = NULL;
 563		} else {
 564			desc_tx->callback = rspi_dma_complete;
 565			desc_tx->callback_param = rspi;
 566		}
 567		cookie = dmaengine_submit(desc_tx);
 568		if (dma_submit_error(cookie)) {
 569			ret = cookie;
 570			goto no_dma_tx;
 571		}
 572
 573		irq_mask |= SPCR_SPTIE;
 574	}
 575
 576	/*
 577	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
 578	 * called. So, this driver disables the IRQ while DMA transfer.
 579	 */
 580	if (tx)
 581		disable_irq(other_irq = rspi->tx_irq);
 582	if (rx && rspi->rx_irq != other_irq)
 583		disable_irq(rspi->rx_irq);
 584
 585	rspi_enable_irq(rspi, irq_mask);
 
 586	rspi->dma_callbacked = 0;
 587
 588	/* Now start DMA */
 589	if (rx)
 590		dma_async_issue_pending(rspi->ctlr->dma_rx);
 591	if (tx)
 592		dma_async_issue_pending(rspi->ctlr->dma_tx);
 593
 594	ret = wait_event_interruptible_timeout(rspi->wait,
 595					       rspi->dma_callbacked, HZ);
 596	if (ret > 0 && rspi->dma_callbacked) {
 597		ret = 0;
 598	} else {
 599		if (!ret) {
 600			dev_err(&rspi->ctlr->dev, "DMA timeout\n");
 601			ret = -ETIMEDOUT;
 602		}
 603		if (tx)
 604			dmaengine_terminate_all(rspi->ctlr->dma_tx);
 605		if (rx)
 606			dmaengine_terminate_all(rspi->ctlr->dma_rx);
 607	}
 608
 609	rspi_disable_irq(rspi, irq_mask);
 610
 611	if (tx)
 612		enable_irq(rspi->tx_irq);
 613	if (rx && rspi->rx_irq != other_irq)
 614		enable_irq(rspi->rx_irq);
 615
 616	return ret;
 617
 618no_dma_tx:
 619	if (rx)
 620		dmaengine_terminate_all(rspi->ctlr->dma_rx);
 621no_dma_rx:
 622	if (ret == -EAGAIN) {
 623		dev_warn_once(&rspi->ctlr->dev,
 624			      "DMA not available, falling back to PIO\n");
 625	}
 626	return ret;
 627}
 628
 629static void rspi_receive_init(const struct rspi_data *rspi)
 630{
 631	u8 spsr;
 632
 633	spsr = rspi_read8(rspi, RSPI_SPSR);
 634	if (spsr & SPSR_SPRF)
 635		rspi_read_data(rspi);	/* dummy read */
 636	if (spsr & SPSR_OVRF)
 637		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
 638			    RSPI_SPSR);
 639}
 640
 641static void rspi_rz_receive_init(const struct rspi_data *rspi)
 642{
 643	rspi_receive_init(rspi);
 644	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
 645	rspi_write8(rspi, 0, RSPI_SPBFCR);
 646}
 647
 648static void qspi_receive_init(const struct rspi_data *rspi)
 649{
 650	u8 spsr;
 651
 652	spsr = rspi_read8(rspi, RSPI_SPSR);
 653	if (spsr & SPSR_SPRF)
 654		rspi_read_data(rspi);   /* dummy read */
 655	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
 656	rspi_write8(rspi, 0, QSPI_SPBFCR);
 657}
 658
 659static bool __rspi_can_dma(const struct rspi_data *rspi,
 660			   const struct spi_transfer *xfer)
 661{
 662	return xfer->len > rspi->ops->fifo_size;
 663}
 664
 665static bool rspi_can_dma(struct spi_controller *ctlr, struct spi_device *spi,
 666			 struct spi_transfer *xfer)
 667{
 668	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
 669
 670	return __rspi_can_dma(rspi, xfer);
 671}
 672
 673static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
 674					 struct spi_transfer *xfer)
 675{
 676	if (!rspi->ctlr->can_dma || !__rspi_can_dma(rspi, xfer))
 677		return -EAGAIN;
 678
 679	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
 680	return rspi_dma_transfer(rspi, &xfer->tx_sg,
 681				xfer->rx_buf ? &xfer->rx_sg : NULL);
 682}
 683
 684static int rspi_common_transfer(struct rspi_data *rspi,
 685				struct spi_transfer *xfer)
 686{
 687	int ret;
 688
 689	ret = rspi_dma_check_then_transfer(rspi, xfer);
 690	if (ret != -EAGAIN)
 691		return ret;
 692
 693	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
 694	if (ret < 0)
 695		return ret;
 696
 697	/* Wait for the last transmission */
 698	rspi_wait_for_tx_empty(rspi);
 699
 700	return 0;
 701}
 702
 703static int rspi_transfer_one(struct spi_controller *ctlr,
 704			     struct spi_device *spi, struct spi_transfer *xfer)
 705{
 706	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
 707	u8 spcr;
 708
 709	spcr = rspi_read8(rspi, RSPI_SPCR);
 710	if (xfer->rx_buf) {
 711		rspi_receive_init(rspi);
 712		spcr &= ~SPCR_TXMD;
 713	} else {
 714		spcr |= SPCR_TXMD;
 715	}
 716	rspi_write8(rspi, spcr, RSPI_SPCR);
 717
 718	return rspi_common_transfer(rspi, xfer);
 719}
 720
 721static int rspi_rz_transfer_one(struct spi_controller *ctlr,
 722				struct spi_device *spi,
 723				struct spi_transfer *xfer)
 724{
 725	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
 726
 727	rspi_rz_receive_init(rspi);
 728
 729	return rspi_common_transfer(rspi, xfer);
 730}
 731
 732static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
 733					u8 *rx, unsigned int len)
 734{
 735	unsigned int i, n;
 736	int ret;
 737
 738	while (len > 0) {
 739		n = qspi_set_send_trigger(rspi, len);
 740		qspi_set_receive_trigger(rspi, len);
 741		ret = rspi_wait_for_tx_empty(rspi);
 742		if (ret < 0) {
 743			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
 744			return ret;
 745		}
 746		for (i = 0; i < n; i++)
 747			rspi_write_data(rspi, *tx++);
 748
 749		ret = rspi_wait_for_rx_full(rspi);
 750		if (ret < 0) {
 751			dev_err(&rspi->ctlr->dev, "receive timeout\n");
 752			return ret;
 753		}
 754		for (i = 0; i < n; i++)
 755			*rx++ = rspi_read_data(rspi);
 756
 757		len -= n;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 758	}
 759
 760	return 0;
 761}
 762
 763static int qspi_transfer_out_in(struct rspi_data *rspi,
 764				struct spi_transfer *xfer)
 765{
 766	int ret;
 767
 768	qspi_receive_init(rspi);
 769
 770	ret = rspi_dma_check_then_transfer(rspi, xfer);
 771	if (ret != -EAGAIN)
 772		return ret;
 773
 774	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
 775					    xfer->rx_buf, xfer->len);
 776}
 777
 778static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
 779{
 780	const u8 *tx = xfer->tx_buf;
 781	unsigned int n = xfer->len;
 782	unsigned int i, len;
 783	int ret;
 784
 785	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
 786		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
 787		if (ret != -EAGAIN)
 788			return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 789	}
 790
 791	while (n > 0) {
 792		len = qspi_set_send_trigger(rspi, n);
 793		ret = rspi_wait_for_tx_empty(rspi);
 794		if (ret < 0) {
 795			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
 796			return ret;
 797		}
 798		for (i = 0; i < len; i++)
 799			rspi_write_data(rspi, *tx++);
 800
 801		n -= len;
 802	}
 803
 804	/* Wait for the last transmission */
 805	rspi_wait_for_tx_empty(rspi);
 806
 807	return 0;
 808}
 809
 810static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
 811{
 812	u8 *rx = xfer->rx_buf;
 813	unsigned int n = xfer->len;
 814	unsigned int i, len;
 815	int ret;
 816
 817	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
 818		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
 819		if (ret != -EAGAIN)
 820			return ret;
 821	}
 822
 823	while (n > 0) {
 824		len = qspi_set_receive_trigger(rspi, n);
 825		ret = rspi_wait_for_rx_full(rspi);
 826		if (ret < 0) {
 827			dev_err(&rspi->ctlr->dev, "receive timeout\n");
 828			return ret;
 829		}
 830		for (i = 0; i < len; i++)
 831			*rx++ = rspi_read_data(rspi);
 832
 833		n -= len;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 834	}
 
 835
 836	return 0;
 837}
 838
 839static int qspi_transfer_one(struct spi_controller *ctlr,
 840			     struct spi_device *spi, struct spi_transfer *xfer)
 841{
 842	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
 843
 844	if (spi->mode & SPI_LOOP) {
 845		return qspi_transfer_out_in(rspi, xfer);
 846	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
 847		/* Quad or Dual SPI Write */
 848		return qspi_transfer_out(rspi, xfer);
 849	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
 850		/* Quad or Dual SPI Read */
 851		return qspi_transfer_in(rspi, xfer);
 852	} else {
 853		/* Single SPI Transfer */
 854		return qspi_transfer_out_in(rspi, xfer);
 855	}
 856}
 857
 858static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
 859{
 860	if (xfer->tx_buf)
 861		switch (xfer->tx_nbits) {
 862		case SPI_NBITS_QUAD:
 863			return SPCMD_SPIMOD_QUAD;
 864		case SPI_NBITS_DUAL:
 865			return SPCMD_SPIMOD_DUAL;
 866		default:
 867			return 0;
 868		}
 869	if (xfer->rx_buf)
 870		switch (xfer->rx_nbits) {
 871		case SPI_NBITS_QUAD:
 872			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
 873		case SPI_NBITS_DUAL:
 874			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
 875		default:
 876			return 0;
 877		}
 878
 879	return 0;
 880}
 881
 882static int qspi_setup_sequencer(struct rspi_data *rspi,
 883				const struct spi_message *msg)
 884{
 885	const struct spi_transfer *xfer;
 886	unsigned int i = 0, len = 0;
 887	u16 current_mode = 0xffff, mode;
 888
 889	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
 890		mode = qspi_transfer_mode(xfer);
 891		if (mode == current_mode) {
 892			len += xfer->len;
 893			continue;
 894		}
 895
 896		/* Transfer mode change */
 897		if (i) {
 898			/* Set transfer data length of previous transfer */
 899			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
 900		}
 901
 902		if (i >= QSPI_NUM_SPCMD) {
 903			dev_err(&msg->spi->dev,
 904				"Too many different transfer modes");
 905			return -EINVAL;
 906		}
 907
 908		/* Program transfer mode for this transfer */
 909		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
 910		current_mode = mode;
 911		len = xfer->len;
 912		i++;
 913	}
 914	if (i) {
 915		/* Set final transfer data length and sequence length */
 916		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
 917		rspi_write8(rspi, i - 1, RSPI_SPSCR);
 918	}
 919
 920	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 921}
 922
 923static int rspi_setup(struct spi_device *spi)
 924{
 925	struct rspi_data *rspi = spi_controller_get_devdata(spi->controller);
 926	u8 sslp;
 927
 928	if (spi->cs_gpiod)
 929		return 0;
 
 930
 931	pm_runtime_get_sync(&rspi->pdev->dev);
 932	spin_lock_irq(&rspi->lock);
 933
 934	sslp = rspi_read8(rspi, RSPI_SSLP);
 935	if (spi->mode & SPI_CS_HIGH)
 936		sslp |= SSLP_SSLP(spi->chip_select);
 937	else
 938		sslp &= ~SSLP_SSLP(spi->chip_select);
 939	rspi_write8(rspi, sslp, RSPI_SSLP);
 940
 941	spin_unlock_irq(&rspi->lock);
 942	pm_runtime_put(&rspi->pdev->dev);
 943	return 0;
 944}
 945
 946static int rspi_prepare_message(struct spi_controller *ctlr,
 947				struct spi_message *msg)
 948{
 949	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
 950	struct spi_device *spi = msg->spi;
 951	const struct spi_transfer *xfer;
 952	int ret;
 953
 954	/*
 955	 * As the Bit Rate Register must not be changed while the device is
 956	 * active, all transfers in a message must use the same bit rate.
 957	 * In theory, the sequencer could be enabled, and each Command Register
 958	 * could divide the base bit rate by a different value.
 959	 * However, most RSPI variants do not have Transfer Data Length
 960	 * Multiplier Setting Registers, so each sequence step would be limited
 961	 * to a single word, making this feature unsuitable for large
 962	 * transfers, which would gain most from it.
 963	 */
 964	rspi->speed_hz = spi->max_speed_hz;
 965	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
 966		if (xfer->speed_hz < rspi->speed_hz)
 967			rspi->speed_hz = xfer->speed_hz;
 968	}
 969
 970	rspi->spcmd = SPCMD_SSLKP;
 971	if (spi->mode & SPI_CPOL)
 972		rspi->spcmd |= SPCMD_CPOL;
 973	if (spi->mode & SPI_CPHA)
 974		rspi->spcmd |= SPCMD_CPHA;
 975	if (spi->mode & SPI_LSB_FIRST)
 976		rspi->spcmd |= SPCMD_LSBF;
 977
 978	/* Configure slave signal to assert */
 979	rspi->spcmd |= SPCMD_SSLA(spi->cs_gpiod ? rspi->ctlr->unused_native_cs
 980						: spi->chip_select);
 981
 982	/* CMOS output mode and MOSI signal from previous transfer */
 983	rspi->sppcr = 0;
 984	if (spi->mode & SPI_LOOP)
 985		rspi->sppcr |= SPPCR_SPLP;
 986
 987	rspi->ops->set_config_register(rspi, 8);
 988
 989	if (msg->spi->mode &
 990	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
 991		/* Setup sequencer for messages with multiple transfer modes */
 992		ret = qspi_setup_sequencer(rspi, msg);
 993		if (ret < 0)
 994			return ret;
 995	}
 996
 997	/* Enable SPI function in master mode */
 998	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
 999	return 0;
1000}
1001
1002static int rspi_unprepare_message(struct spi_controller *ctlr,
1003				  struct spi_message *msg)
1004{
1005	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
1006
1007	/* Disable SPI function */
1008	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
1009
1010	/* Reset sequencer for Single SPI Transfers */
1011	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
1012	rspi_write8(rspi, 0, RSPI_SPSCR);
1013	return 0;
1014}
1015
1016static irqreturn_t rspi_irq_mux(int irq, void *_sr)
1017{
1018	struct rspi_data *rspi = _sr;
1019	u8 spsr;
1020	irqreturn_t ret = IRQ_NONE;
1021	u8 disable_irq = 0;
1022
1023	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1024	if (spsr & SPSR_SPRF)
1025		disable_irq |= SPCR_SPRIE;
1026	if (spsr & SPSR_SPTEF)
1027		disable_irq |= SPCR_SPTIE;
1028
1029	if (disable_irq) {
1030		ret = IRQ_HANDLED;
1031		rspi_disable_irq(rspi, disable_irq);
1032		wake_up(&rspi->wait);
1033	}
1034
1035	return ret;
1036}
1037
1038static irqreturn_t rspi_irq_rx(int irq, void *_sr)
1039{
1040	struct rspi_data *rspi = _sr;
1041	u8 spsr;
1042
1043	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1044	if (spsr & SPSR_SPRF) {
1045		rspi_disable_irq(rspi, SPCR_SPRIE);
1046		wake_up(&rspi->wait);
1047		return IRQ_HANDLED;
1048	}
1049
1050	return 0;
1051}
1052
1053static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1054{
1055	struct rspi_data *rspi = _sr;
1056	u8 spsr;
1057
1058	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1059	if (spsr & SPSR_SPTEF) {
1060		rspi_disable_irq(rspi, SPCR_SPTIE);
1061		wake_up(&rspi->wait);
1062		return IRQ_HANDLED;
1063	}
1064
1065	return 0;
1066}
1067
1068static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1069					      enum dma_transfer_direction dir,
1070					      unsigned int id,
1071					      dma_addr_t port_addr)
1072{
 
1073	dma_cap_mask_t mask;
1074	struct dma_chan *chan;
1075	struct dma_slave_config cfg;
1076	int ret;
1077
1078	dma_cap_zero(mask);
1079	dma_cap_set(DMA_SLAVE, mask);
1080
1081	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1082				(void *)(unsigned long)id, dev,
1083				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1084	if (!chan) {
1085		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1086		return NULL;
1087	}
1088
1089	memset(&cfg, 0, sizeof(cfg));
1090	cfg.direction = dir;
1091	if (dir == DMA_MEM_TO_DEV) {
1092		cfg.dst_addr = port_addr;
1093		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1094	} else {
1095		cfg.src_addr = port_addr;
1096		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1097	}
1098
1099	ret = dmaengine_slave_config(chan, &cfg);
1100	if (ret) {
1101		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1102		dma_release_channel(chan);
1103		return NULL;
 
 
 
 
1104	}
1105
1106	return chan;
1107}
1108
1109static int rspi_request_dma(struct device *dev, struct spi_controller *ctlr,
1110			    const struct resource *res)
1111{
1112	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1113	unsigned int dma_tx_id, dma_rx_id;
1114
1115	if (dev->of_node) {
1116		/* In the OF case we will get the slave IDs from the DT */
1117		dma_tx_id = 0;
1118		dma_rx_id = 0;
1119	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1120		dma_tx_id = rspi_pd->dma_tx_id;
1121		dma_rx_id = rspi_pd->dma_rx_id;
1122	} else {
1123		/* The driver assumes no error. */
1124		return 0;
1125	}
1126
1127	ctlr->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1128					     res->start + RSPI_SPDR);
1129	if (!ctlr->dma_tx)
1130		return -ENODEV;
1131
1132	ctlr->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1133					     res->start + RSPI_SPDR);
1134	if (!ctlr->dma_rx) {
1135		dma_release_channel(ctlr->dma_tx);
1136		ctlr->dma_tx = NULL;
1137		return -ENODEV;
1138	}
1139
1140	ctlr->can_dma = rspi_can_dma;
1141	dev_info(dev, "DMA available");
1142	return 0;
1143}
1144
1145static void rspi_release_dma(struct spi_controller *ctlr)
1146{
1147	if (ctlr->dma_tx)
1148		dma_release_channel(ctlr->dma_tx);
1149	if (ctlr->dma_rx)
1150		dma_release_channel(ctlr->dma_rx);
1151}
1152
1153static int rspi_remove(struct platform_device *pdev)
1154{
1155	struct rspi_data *rspi = platform_get_drvdata(pdev);
1156
1157	rspi_release_dma(rspi->ctlr);
1158	pm_runtime_disable(&pdev->dev);
 
 
 
 
1159
1160	return 0;
1161}
1162
1163static const struct spi_ops rspi_ops = {
1164	.set_config_register =	rspi_set_config_register,
1165	.transfer_one =		rspi_transfer_one,
1166	.flags =		SPI_CONTROLLER_MUST_TX,
1167	.fifo_size =		8,
1168	.num_hw_ss =		2,
1169};
1170
1171static const struct spi_ops rspi_rz_ops = {
1172	.set_config_register =	rspi_rz_set_config_register,
1173	.transfer_one =		rspi_rz_transfer_one,
1174	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1175	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1176	.num_hw_ss =		1,
1177};
1178
1179static const struct spi_ops qspi_ops = {
1180	.set_config_register =	qspi_set_config_register,
1181	.transfer_one =		qspi_transfer_one,
1182	.extra_mode_bits =	SPI_TX_DUAL | SPI_TX_QUAD |
1183				SPI_RX_DUAL | SPI_RX_QUAD,
1184	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1185	.fifo_size =		32,
1186	.num_hw_ss =		1,
1187};
1188
1189#ifdef CONFIG_OF
1190static const struct of_device_id rspi_of_match[] = {
1191	/* RSPI on legacy SH */
1192	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1193	/* RSPI on RZ/A1H */
1194	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1195	/* QSPI on R-Car Gen2 */
1196	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1197	{ /* sentinel */ }
1198};
1199
1200MODULE_DEVICE_TABLE(of, rspi_of_match);
1201
1202static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1203{
1204	u32 num_cs;
1205	int error;
1206
1207	/* Parse DT properties */
1208	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1209	if (error) {
1210		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1211		return error;
1212	}
1213
1214	ctlr->num_chipselect = num_cs;
1215	return 0;
1216}
1217#else
1218#define rspi_of_match	NULL
1219static inline int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1220{
1221	return -EINVAL;
1222}
1223#endif /* CONFIG_OF */
1224
1225static int rspi_request_irq(struct device *dev, unsigned int irq,
1226			    irq_handler_t handler, const char *suffix,
1227			    void *dev_id)
1228{
1229	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1230					  dev_name(dev), suffix);
1231	if (!name)
1232		return -ENOMEM;
1233
1234	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1235}
1236
1237static int rspi_probe(struct platform_device *pdev)
1238{
1239	struct resource *res;
1240	struct spi_controller *ctlr;
1241	struct rspi_data *rspi;
1242	int ret;
1243	const struct rspi_plat_data *rspi_pd;
1244	const struct spi_ops *ops;
1245
1246	ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1247	if (ctlr == NULL)
1248		return -ENOMEM;
 
 
 
1249
1250	ops = of_device_get_match_data(&pdev->dev);
1251	if (ops) {
1252		ret = rspi_parse_dt(&pdev->dev, ctlr);
1253		if (ret)
1254			goto error1;
1255	} else {
1256		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1257		rspi_pd = dev_get_platdata(&pdev->dev);
1258		if (rspi_pd && rspi_pd->num_chipselect)
1259			ctlr->num_chipselect = rspi_pd->num_chipselect;
1260		else
1261			ctlr->num_chipselect = 2; /* default */
1262	}
1263
1264	/* ops parameter check */
1265	if (!ops->set_config_register) {
1266		dev_err(&pdev->dev, "there is no set_config_register\n");
1267		ret = -ENODEV;
1268		goto error1;
1269	}
1270
1271	rspi = spi_controller_get_devdata(ctlr);
1272	platform_set_drvdata(pdev, rspi);
1273	rspi->ops = ops;
1274	rspi->ctlr = ctlr;
1275
1276	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1277	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1278	if (IS_ERR(rspi->addr)) {
1279		ret = PTR_ERR(rspi->addr);
 
1280		goto error1;
1281	}
1282
1283	rspi->clk = devm_clk_get(&pdev->dev, NULL);
 
1284	if (IS_ERR(rspi->clk)) {
1285		dev_err(&pdev->dev, "cannot get clock\n");
1286		ret = PTR_ERR(rspi->clk);
1287		goto error1;
1288	}
 
1289
1290	rspi->pdev = pdev;
1291	pm_runtime_enable(&pdev->dev);
1292
1293	init_waitqueue_head(&rspi->wait);
1294	spin_lock_init(&rspi->lock);
 
 
1295
1296	ctlr->bus_num = pdev->id;
1297	ctlr->setup = rspi_setup;
1298	ctlr->auto_runtime_pm = true;
1299	ctlr->transfer_one = ops->transfer_one;
1300	ctlr->prepare_message = rspi_prepare_message;
1301	ctlr->unprepare_message = rspi_unprepare_message;
1302	ctlr->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
1303			  SPI_LOOP | ops->extra_mode_bits;
1304	ctlr->flags = ops->flags;
1305	ctlr->dev.of_node = pdev->dev.of_node;
1306	ctlr->use_gpio_descriptors = true;
1307	ctlr->max_native_cs = rspi->ops->num_hw_ss;
1308
1309	ret = platform_get_irq_byname_optional(pdev, "rx");
1310	if (ret < 0) {
1311		ret = platform_get_irq_byname_optional(pdev, "mux");
1312		if (ret < 0)
1313			ret = platform_get_irq(pdev, 0);
1314		if (ret >= 0)
1315			rspi->rx_irq = rspi->tx_irq = ret;
1316	} else {
1317		rspi->rx_irq = ret;
1318		ret = platform_get_irq_byname(pdev, "tx");
1319		if (ret >= 0)
1320			rspi->tx_irq = ret;
1321	}
1322
1323	if (rspi->rx_irq == rspi->tx_irq) {
1324		/* Single multiplexed interrupt */
1325		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1326				       "mux", rspi);
1327	} else {
1328		/* Multi-interrupt mode, only SPRI and SPTI are used */
1329		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1330				       "rx", rspi);
1331		if (!ret)
1332			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1333					       rspi_irq_tx, "tx", rspi);
1334	}
1335	if (ret < 0) {
1336		dev_err(&pdev->dev, "request_irq error\n");
1337		goto error2;
1338	}
1339
1340	ret = rspi_request_dma(&pdev->dev, ctlr, res);
1341	if (ret < 0)
1342		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1343
1344	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1345	if (ret < 0) {
1346		dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1347		goto error3;
1348	}
1349
1350	dev_info(&pdev->dev, "probed\n");
1351
1352	return 0;
1353
 
 
 
1354error3:
1355	rspi_release_dma(ctlr);
1356error2:
1357	pm_runtime_disable(&pdev->dev);
1358error1:
1359	spi_controller_put(ctlr);
1360
1361	return ret;
1362}
1363
1364static const struct platform_device_id spi_driver_ids[] = {
1365	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1366	{},
1367};
1368
1369MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1370
1371#ifdef CONFIG_PM_SLEEP
1372static int rspi_suspend(struct device *dev)
1373{
1374	struct rspi_data *rspi = dev_get_drvdata(dev);
1375
1376	return spi_controller_suspend(rspi->ctlr);
1377}
1378
1379static int rspi_resume(struct device *dev)
1380{
1381	struct rspi_data *rspi = dev_get_drvdata(dev);
1382
1383	return spi_controller_resume(rspi->ctlr);
1384}
1385
1386static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1387#define DEV_PM_OPS	&rspi_pm_ops
1388#else
1389#define DEV_PM_OPS	NULL
1390#endif /* CONFIG_PM_SLEEP */
1391
1392static struct platform_driver rspi_driver = {
1393	.probe =	rspi_probe,
1394	.remove =	rspi_remove,
1395	.id_table =	spi_driver_ids,
1396	.driver		= {
1397		.name = "renesas_spi",
1398		.pm = DEV_PM_OPS,
1399		.of_match_table = of_match_ptr(rspi_of_match),
1400	},
1401};
1402module_platform_driver(rspi_driver);
1403
1404MODULE_DESCRIPTION("Renesas RSPI bus driver");
1405MODULE_LICENSE("GPL v2");
1406MODULE_AUTHOR("Yoshihiro Shimoda");
1407MODULE_ALIAS("platform:rspi");
v3.5.6
 
  1/*
  2 * SH RSPI driver
  3 *
  4 * Copyright (C) 2012  Renesas Solutions Corp.
 
  5 *
  6 * Based on spi-sh.c:
  7 * Copyright (C) 2011 Renesas Solutions Corp.
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; version 2 of the License.
 12 *
 13 * This program is distributed in the hope that it will be useful,
 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16 * GNU General Public License for more details.
 17 *
 18 * You should have received a copy of the GNU General Public License
 19 * along with this program; if not, write to the Free Software
 20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 21 *
 22 */
 23
 24#include <linux/module.h>
 25#include <linux/kernel.h>
 26#include <linux/sched.h>
 27#include <linux/errno.h>
 28#include <linux/list.h>
 29#include <linux/workqueue.h>
 30#include <linux/interrupt.h>
 31#include <linux/platform_device.h>
 32#include <linux/io.h>
 33#include <linux/clk.h>
 34#include <linux/dmaengine.h>
 35#include <linux/dma-mapping.h>
 
 
 36#include <linux/sh_dma.h>
 37#include <linux/spi/spi.h>
 38#include <linux/spi/rspi.h>
 
 39
 40#define RSPI_SPCR		0x00
 41#define RSPI_SSLP		0x01
 42#define RSPI_SPPCR		0x02
 43#define RSPI_SPSR		0x03
 44#define RSPI_SPDR		0x04
 45#define RSPI_SPSCR		0x08
 46#define RSPI_SPSSR		0x09
 47#define RSPI_SPBR		0x0a
 48#define RSPI_SPDCR		0x0b
 49#define RSPI_SPCKD		0x0c
 50#define RSPI_SSLND		0x0d
 51#define RSPI_SPND		0x0e
 52#define RSPI_SPCR2		0x0f
 53#define RSPI_SPCMD0		0x10
 54#define RSPI_SPCMD1		0x12
 55#define RSPI_SPCMD2		0x14
 56#define RSPI_SPCMD3		0x16
 57#define RSPI_SPCMD4		0x18
 58#define RSPI_SPCMD5		0x1a
 59#define RSPI_SPCMD6		0x1c
 60#define RSPI_SPCMD7		0x1e
 61
 62/* SPCR */
 63#define SPCR_SPRIE		0x80
 64#define SPCR_SPE		0x40
 65#define SPCR_SPTIE		0x20
 66#define SPCR_SPEIE		0x10
 67#define SPCR_MSTR		0x08
 68#define SPCR_MODFEN		0x04
 69#define SPCR_TXMD		0x02
 70#define SPCR_SPMS		0x01
 71
 72/* SSLP */
 73#define SSLP_SSL1P		0x02
 74#define SSLP_SSL0P		0x01
 75
 76/* SPPCR */
 77#define SPPCR_MOIFE		0x20
 78#define SPPCR_MOIFV		0x10
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 79#define SPPCR_SPOM		0x04
 80#define SPPCR_SPLP2		0x02
 81#define SPPCR_SPLP		0x01
 
 
 
 82
 83/* SPSR */
 84#define SPSR_SPRF		0x80
 85#define SPSR_SPTEF		0x20
 86#define SPSR_PERF		0x08
 87#define SPSR_MODF		0x04
 88#define SPSR_IDLNF		0x02
 89#define SPSR_OVRF		0x01
 90
 91/* SPSCR */
 92#define SPSCR_SPSLN_MASK	0x07
 93
 94/* SPSSR */
 95#define SPSSR_SPECM_MASK	0x70
 96#define SPSSR_SPCP_MASK		0x07
 97
 98/* SPDCR */
 99#define SPDCR_SPLW		0x20
100#define SPDCR_SPRDTD		0x10
 
 
 
 
 
 
 
101#define SPDCR_SLSEL1		0x08
102#define SPDCR_SLSEL0		0x04
103#define SPDCR_SLSEL_MASK	0x0c
104#define SPDCR_SPFC1		0x02
105#define SPDCR_SPFC0		0x01
 
106
107/* SPCKD */
108#define SPCKD_SCKDL_MASK	0x07
109
110/* SSLND */
111#define SSLND_SLNDL_MASK	0x07
112
113/* SPND */
114#define SPND_SPNDL_MASK		0x07
115
116/* SPCR2 */
117#define SPCR2_PTE		0x08
118#define SPCR2_SPIE		0x04
119#define SPCR2_SPOE		0x02
120#define SPCR2_SPPE		0x01
121
122/* SPCMDn */
123#define SPCMD_SCKDEN		0x8000
124#define SPCMD_SLNDEN		0x4000
125#define SPCMD_SPNDEN		0x2000
126#define SPCMD_LSBF		0x1000
127#define SPCMD_SPB_MASK		0x0f00
 
 
 
128#define SPCMD_SPB_8_TO_16(bit)	(((bit - 1) << 8) & SPCMD_SPB_MASK)
 
 
129#define SPCMD_SPB_20BIT		0x0000
130#define SPCMD_SPB_24BIT		0x0100
131#define SPCMD_SPB_32BIT		0x0200
132#define SPCMD_SSLKP		0x0080
133#define SPCMD_SSLA_MASK		0x0030
134#define SPCMD_BRDV_MASK		0x000c
135#define SPCMD_CPOL		0x0002
136#define SPCMD_CPHA		0x0001
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
137
138struct rspi_data {
139	void __iomem *addr;
140	u32 max_speed_hz;
141	struct spi_master *master;
142	struct list_head queue;
143	struct work_struct ws;
144	wait_queue_head_t wait;
145	spinlock_t lock;
146	struct clk *clk;
147	unsigned char spsr;
148
149	/* for dmaengine */
150	struct sh_dmae_slave dma_tx;
151	struct sh_dmae_slave dma_rx;
152	struct dma_chan *chan_tx;
153	struct dma_chan *chan_rx;
154	int irq;
155
156	unsigned dma_width_16bit:1;
157	unsigned dma_callbacked:1;
 
158};
159
160static void rspi_write8(struct rspi_data *rspi, u8 data, u16 offset)
161{
162	iowrite8(data, rspi->addr + offset);
163}
164
165static void rspi_write16(struct rspi_data *rspi, u16 data, u16 offset)
166{
167	iowrite16(data, rspi->addr + offset);
168}
169
170static u8 rspi_read8(struct rspi_data *rspi, u16 offset)
 
 
 
 
 
171{
172	return ioread8(rspi->addr + offset);
173}
174
175static u16 rspi_read16(struct rspi_data *rspi, u16 offset)
176{
177	return ioread16(rspi->addr + offset);
178}
179
180static unsigned char rspi_calc_spbr(struct rspi_data *rspi)
181{
182	int tmp;
183	unsigned char spbr;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
184
185	tmp = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
186	spbr = clamp(tmp, 0, 255);
 
187
188	return spbr;
189}
 
190
191static void rspi_enable_irq(struct rspi_data *rspi, u8 enable)
192{
193	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
194}
195
196static void rspi_disable_irq(struct rspi_data *rspi, u8 disable)
197{
198	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
199}
200
201static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
202				   u8 enable_bit)
203{
204	int ret;
205
206	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
207	rspi_enable_irq(rspi, enable_bit);
208	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
209	if (ret == 0 && !(rspi->spsr & wait_mask))
210		return -ETIMEDOUT;
211
212	return 0;
213}
214
215static void rspi_assert_ssl(struct rspi_data *rspi)
 
 
 
216{
217	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
218}
219
220static void rspi_negate_ssl(struct rspi_data *rspi)
 
 
 
221{
222	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
223}
224
225static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
226{
227	/* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
228	rspi_write8(rspi, 0x00, RSPI_SPPCR);
229
230	/* Sets transfer bit rate */
231	rspi_write8(rspi, rspi_calc_spbr(rspi), RSPI_SPBR);
 
232
233	/* Sets number of frames to be used: 1 frame */
234	rspi_write8(rspi, 0x00, RSPI_SPDCR);
 
235
236	/* Sets RSPCK, SSL, next-access delay value */
237	rspi_write8(rspi, 0x00, RSPI_SPCKD);
238	rspi_write8(rspi, 0x00, RSPI_SSLND);
239	rspi_write8(rspi, 0x00, RSPI_SPND);
240
241	/* Sets parity, interrupt mask */
242	rspi_write8(rspi, 0x00, RSPI_SPCR2);
243
244	/* Sets SPCMD */
245	rspi_write16(rspi, SPCMD_SPB_8_TO_16(access_size) | SPCMD_SSLKP,
246		     RSPI_SPCMD0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
247
248	/* Sets RSPI mode */
249	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
250
251	return 0;
252}
253
254static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
255			 struct spi_transfer *t)
256{
257	int remain = t->len;
258	u8 *data;
259
260	data = (u8 *)t->tx_buf;
261	while (remain > 0) {
262		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD,
263			    RSPI_SPCR);
 
 
 
 
 
 
264
265		if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
266			dev_err(&rspi->master->dev,
267				"%s: tx empty timeout\n", __func__);
268			return -ETIMEDOUT;
269		}
270
271		rspi_write16(rspi, *data, RSPI_SPDR);
272		data++;
273		remain--;
 
 
 
 
 
274	}
275
276	/* Waiting for the last transmition */
277	rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
 
 
 
 
278
279	return 0;
 
 
 
 
 
 
 
 
 
 
 
280}
281
282static void rspi_dma_complete(void *arg)
283{
284	struct rspi_data *rspi = arg;
 
285
286	rspi->dma_callbacked = 1;
287	wake_up_interruptible(&rspi->wait);
 
288}
289
290static int rspi_dma_map_sg(struct scatterlist *sg, void *buf, unsigned len,
291			   struct dma_chan *chan,
292			   enum dma_transfer_direction dir)
293{
294	sg_init_table(sg, 1);
295	sg_set_buf(sg, buf, len);
296	sg_dma_len(sg) = len;
297	return dma_map_sg(chan->device->dev, sg, 1, dir);
 
 
 
 
 
 
 
 
298}
299
300static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan,
301			      enum dma_transfer_direction dir)
302{
303	dma_unmap_sg(chan->device->dev, sg, 1, dir);
304}
305
306static void rspi_memory_to_8bit(void *buf, const void *data, unsigned len)
307{
308	u16 *dst = buf;
309	const u8 *src = data;
310
311	while (len) {
312		*dst++ = (u16)(*src++);
313		len--;
 
 
 
314	}
 
 
315}
316
317static void rspi_memory_from_8bit(void *buf, const void *data, unsigned len)
318{
319	u8 *dst = buf;
320	const u16 *src = data;
 
 
 
 
 
 
 
 
 
321
322	while (len) {
323		*dst++ = (u8)*src++;
324		len--;
 
 
 
 
 
 
 
 
 
 
 
 
325	}
 
 
326}
327
328static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
329{
330	struct scatterlist sg;
331	void *buf = NULL;
332	struct dma_async_tx_descriptor *desc;
333	unsigned len;
334	int ret = 0;
335
336	if (rspi->dma_width_16bit) {
337		/*
338		 * If DMAC bus width is 16-bit, the driver allocates a dummy
339		 * buffer. And, the driver converts original data into the
340		 * DMAC data as the following format:
341		 *  original data: 1st byte, 2nd byte ...
342		 *  DMAC data:     1st byte, dummy, 2nd byte, dummy ...
343		 */
344		len = t->len * 2;
345		buf = kmalloc(len, GFP_KERNEL);
346		if (!buf)
347			return -ENOMEM;
348		rspi_memory_to_8bit(buf, t->tx_buf, t->len);
349	} else {
350		len = t->len;
351		buf = (void *)t->tx_buf;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
352	}
353
354	if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE)) {
355		ret = -EFAULT;
356		goto end_nomap;
357	}
358	desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE,
359				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
360	if (!desc) {
361		ret = -EIO;
362		goto end;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
363	}
364
365	/*
366	 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
367	 * called. So, this driver disables the IRQ while DMA transfer.
368	 */
369	disable_irq(rspi->irq);
 
 
 
370
371	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, RSPI_SPCR);
372	rspi_enable_irq(rspi, SPCR_SPTIE);
373	rspi->dma_callbacked = 0;
374
375	desc->callback = rspi_dma_complete;
376	desc->callback_param = rspi;
377	dmaengine_submit(desc);
378	dma_async_issue_pending(rspi->chan_tx);
 
379
380	ret = wait_event_interruptible_timeout(rspi->wait,
381					       rspi->dma_callbacked, HZ);
382	if (ret > 0 && rspi->dma_callbacked)
383		ret = 0;
384	else if (!ret)
385		ret = -ETIMEDOUT;
386	rspi_disable_irq(rspi, SPCR_SPTIE);
387
388	enable_irq(rspi->irq);
389
390end:
391	rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE);
392end_nomap:
393	if (rspi->dma_width_16bit)
394		kfree(buf);
 
 
 
 
 
 
395
396	return ret;
 
 
 
 
 
 
 
 
 
 
397}
398
399static void rspi_receive_init(struct rspi_data *rspi)
400{
401	unsigned char spsr;
402
403	spsr = rspi_read8(rspi, RSPI_SPSR);
404	if (spsr & SPSR_SPRF)
405		rspi_read16(rspi, RSPI_SPDR);	/* dummy read */
406	if (spsr & SPSR_OVRF)
407		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
408			    RSPI_SPCR);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
409}
410
411static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
412			    struct spi_transfer *t)
413{
414	int remain = t->len;
415	u8 *data;
416
417	rspi_receive_init(rspi);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
418
419	data = (u8 *)t->rx_buf;
420	while (remain > 0) {
421		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD,
422			    RSPI_SPCR);
423
424		if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
425			dev_err(&rspi->master->dev,
426				"%s: tx empty timeout\n", __func__);
427			return -ETIMEDOUT;
428		}
429		/* dummy write for generate clock */
430		rspi_write16(rspi, 0x00, RSPI_SPDR);
431
432		if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
433			dev_err(&rspi->master->dev,
434				"%s: receive timeout\n", __func__);
435			return -ETIMEDOUT;
436		}
437		/* SPDR allows 16 or 32-bit access only */
438		*data = (u8)rspi_read16(rspi, RSPI_SPDR);
439
440		data++;
441		remain--;
442	}
443
444	return 0;
445}
446
447static int rspi_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
448{
449	struct scatterlist sg, sg_dummy;
450	void *dummy = NULL, *rx_buf = NULL;
451	struct dma_async_tx_descriptor *desc, *desc_dummy;
452	unsigned len;
453	int ret = 0;
454
455	if (rspi->dma_width_16bit) {
456		/*
457		 * If DMAC bus width is 16-bit, the driver allocates a dummy
458		 * buffer. And, finally the driver converts the DMAC data into
459		 * actual data as the following format:
460		 *  DMAC data:   1st byte, dummy, 2nd byte, dummy ...
461		 *  actual data: 1st byte, 2nd byte ...
462		 */
463		len = t->len * 2;
464		rx_buf = kmalloc(len, GFP_KERNEL);
465		if (!rx_buf)
466			return -ENOMEM;
467	 } else {
468		len = t->len;
469		rx_buf = t->rx_buf;
470	}
471
472	/* prepare dummy transfer to generate SPI clocks */
473	dummy = kzalloc(len, GFP_KERNEL);
474	if (!dummy) {
475		ret = -ENOMEM;
476		goto end_nomap;
477	}
478	if (!rspi_dma_map_sg(&sg_dummy, dummy, len, rspi->chan_tx,
479			     DMA_TO_DEVICE)) {
480		ret = -EFAULT;
481		goto end_nomap;
482	}
483	desc_dummy = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_dummy, 1,
484			DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
485	if (!desc_dummy) {
486		ret = -EIO;
487		goto end_dummy_mapped;
488	}
489
490	/* prepare receive transfer */
491	if (!rspi_dma_map_sg(&sg, rx_buf, len, rspi->chan_rx,
492			     DMA_FROM_DEVICE)) {
493		ret = -EFAULT;
494		goto end_dummy_mapped;
495
496	}
497	desc = dmaengine_prep_slave_sg(rspi->chan_rx, &sg, 1, DMA_FROM_DEVICE,
498				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
499	if (!desc) {
500		ret = -EIO;
501		goto end;
502	}
503
504	rspi_receive_init(rspi);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
505
506	/*
507	 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
508	 * called. So, this driver disables the IRQ while DMA transfer.
509	 */
510	disable_irq(rspi->irq);
 
511
512	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, RSPI_SPCR);
513	rspi_enable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
514	rspi->dma_callbacked = 0;
 
 
515
516	desc->callback = rspi_dma_complete;
517	desc->callback_param = rspi;
518	dmaengine_submit(desc);
519	dma_async_issue_pending(rspi->chan_rx);
520
521	desc_dummy->callback = NULL;	/* No callback */
522	dmaengine_submit(desc_dummy);
523	dma_async_issue_pending(rspi->chan_tx);
 
524
525	ret = wait_event_interruptible_timeout(rspi->wait,
526					       rspi->dma_callbacked, HZ);
527	if (ret > 0 && rspi->dma_callbacked)
528		ret = 0;
529	else if (!ret)
530		ret = -ETIMEDOUT;
531	rspi_disable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
532
533	enable_irq(rspi->irq);
534
535end:
536	rspi_dma_unmap_sg(&sg, rspi->chan_rx, DMA_FROM_DEVICE);
537end_dummy_mapped:
538	rspi_dma_unmap_sg(&sg_dummy, rspi->chan_tx, DMA_TO_DEVICE);
539end_nomap:
540	if (rspi->dma_width_16bit) {
541		if (!ret)
542			rspi_memory_from_8bit(t->rx_buf, rx_buf, t->len);
543		kfree(rx_buf);
544	}
545	kfree(dummy);
546
547	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
548}
549
550static int rspi_is_dma(struct rspi_data *rspi, struct spi_transfer *t)
551{
552	if (t->tx_buf && rspi->chan_tx)
553		return 1;
554	/* If the module receives data by DMAC, it also needs TX DMAC */
555	if (t->rx_buf && rspi->chan_tx && rspi->chan_rx)
556		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
557
558	return 0;
559}
560
561static void rspi_work(struct work_struct *work)
 
562{
563	struct rspi_data *rspi = container_of(work, struct rspi_data, ws);
564	struct spi_message *mesg;
565	struct spi_transfer *t;
566	unsigned long flags;
567	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
568
569	spin_lock_irqsave(&rspi->lock, flags);
570	while (!list_empty(&rspi->queue)) {
571		mesg = list_entry(rspi->queue.next, struct spi_message, queue);
572		list_del_init(&mesg->queue);
573		spin_unlock_irqrestore(&rspi->lock, flags);
574
575		rspi_assert_ssl(rspi);
576
577		list_for_each_entry(t, &mesg->transfers, transfer_list) {
578			if (t->tx_buf) {
579				if (rspi_is_dma(rspi, t))
580					ret = rspi_send_dma(rspi, t);
581				else
582					ret = rspi_send_pio(rspi, mesg, t);
583				if (ret < 0)
584					goto error;
585			}
586			if (t->rx_buf) {
587				if (rspi_is_dma(rspi, t))
588					ret = rspi_receive_dma(rspi, t);
589				else
590					ret = rspi_receive_pio(rspi, mesg, t);
591				if (ret < 0)
592					goto error;
593			}
594			mesg->actual_length += t->len;
595		}
596		rspi_negate_ssl(rspi);
597
598		mesg->status = 0;
599		mesg->complete(mesg->context);
600
601		spin_lock_irqsave(&rspi->lock, flags);
602	}
603
604	return;
605
606error:
607	mesg->status = ret;
608	mesg->complete(mesg->context);
609}
610
611static int rspi_setup(struct spi_device *spi)
612{
613	struct rspi_data *rspi = spi_master_get_devdata(spi->master);
 
614
615	if (!spi->bits_per_word)
616		spi->bits_per_word = 8;
617	rspi->max_speed_hz = spi->max_speed_hz;
618
619	rspi_set_config_register(rspi, 8);
 
620
 
 
 
 
 
 
 
 
 
621	return 0;
622}
623
624static int rspi_transfer(struct spi_device *spi, struct spi_message *mesg)
 
625{
626	struct rspi_data *rspi = spi_master_get_devdata(spi->master);
627	unsigned long flags;
 
 
628
629	mesg->actual_length = 0;
630	mesg->status = -EINPROGRESS;
631
632	spin_lock_irqsave(&rspi->lock, flags);
633	list_add_tail(&mesg->queue, &rspi->queue);
634	schedule_work(&rspi->ws);
635	spin_unlock_irqrestore(&rspi->lock, flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
636
 
 
637	return 0;
638}
639
640static void rspi_cleanup(struct spi_device *spi)
 
641{
 
 
 
 
 
 
 
 
 
642}
643
644static irqreturn_t rspi_irq(int irq, void *_sr)
645{
646	struct rspi_data *rspi = (struct rspi_data *)_sr;
647	unsigned long spsr;
648	irqreturn_t ret = IRQ_NONE;
649	unsigned char disable_irq = 0;
650
651	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
652	if (spsr & SPSR_SPRF)
653		disable_irq |= SPCR_SPRIE;
654	if (spsr & SPSR_SPTEF)
655		disable_irq |= SPCR_SPTIE;
656
657	if (disable_irq) {
658		ret = IRQ_HANDLED;
659		rspi_disable_irq(rspi, disable_irq);
660		wake_up(&rspi->wait);
661	}
662
663	return ret;
664}
665
666static bool rspi_filter(struct dma_chan *chan, void *filter_param)
667{
668	chan->private = filter_param;
669	return true;
 
 
 
 
 
 
 
 
 
670}
671
672static void __devinit rspi_request_dma(struct rspi_data *rspi,
673				       struct platform_device *pdev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
674{
675	struct rspi_plat_data *rspi_pd = pdev->dev.platform_data;
676	dma_cap_mask_t mask;
 
 
 
677
678	if (!rspi_pd)
679		return;
680
681	rspi->dma_width_16bit = rspi_pd->dma_width_16bit;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
682
683	/* If the module receives data by DMAC, it also needs TX DMAC */
684	if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) {
685		dma_cap_zero(mask);
686		dma_cap_set(DMA_SLAVE, mask);
687		rspi->dma_rx.slave_id = rspi_pd->dma_rx_id;
688		rspi->chan_rx = dma_request_channel(mask, rspi_filter,
689						    &rspi->dma_rx);
690		if (rspi->chan_rx)
691			dev_info(&pdev->dev, "Use DMA when rx.\n");
692	}
693	if (rspi_pd->dma_tx_id) {
694		dma_cap_zero(mask);
695		dma_cap_set(DMA_SLAVE, mask);
696		rspi->dma_tx.slave_id = rspi_pd->dma_tx_id;
697		rspi->chan_tx = dma_request_channel(mask, rspi_filter,
698						    &rspi->dma_tx);
699		if (rspi->chan_tx)
700			dev_info(&pdev->dev, "Use DMA when tx\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
701	}
 
 
 
 
702}
703
704static void __devexit rspi_release_dma(struct rspi_data *rspi)
705{
706	if (rspi->chan_tx)
707		dma_release_channel(rspi->chan_tx);
708	if (rspi->chan_rx)
709		dma_release_channel(rspi->chan_rx);
710}
711
712static int __devexit rspi_remove(struct platform_device *pdev)
713{
714	struct rspi_data *rspi = dev_get_drvdata(&pdev->dev);
715
716	spi_unregister_master(rspi->master);
717	rspi_release_dma(rspi);
718	free_irq(platform_get_irq(pdev, 0), rspi);
719	clk_put(rspi->clk);
720	iounmap(rspi->addr);
721	spi_master_put(rspi->master);
722
723	return 0;
724}
725
726static int __devinit rspi_probe(struct platform_device *pdev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
727{
728	struct resource *res;
729	struct spi_master *master;
730	struct rspi_data *rspi;
731	int ret, irq;
732	char clk_name[16];
 
733
734	/* get base addr */
735	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
736	if (unlikely(res == NULL)) {
737		dev_err(&pdev->dev, "invalid resource\n");
738		return -EINVAL;
739	}
740
741	irq = platform_get_irq(pdev, 0);
742	if (irq < 0) {
743		dev_err(&pdev->dev, "platform_get_irq error\n");
744		return -ENODEV;
 
 
 
 
 
 
 
 
745	}
746
747	master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
748	if (master == NULL) {
749		dev_err(&pdev->dev, "spi_alloc_master error.\n");
750		return -ENOMEM;
 
751	}
752
753	rspi = spi_master_get_devdata(master);
754	dev_set_drvdata(&pdev->dev, rspi);
 
 
755
756	rspi->master = master;
757	rspi->addr = ioremap(res->start, resource_size(res));
758	if (rspi->addr == NULL) {
759		dev_err(&pdev->dev, "ioremap error.\n");
760		ret = -ENOMEM;
761		goto error1;
762	}
763
764	snprintf(clk_name, sizeof(clk_name), "rspi%d", pdev->id);
765	rspi->clk = clk_get(&pdev->dev, clk_name);
766	if (IS_ERR(rspi->clk)) {
767		dev_err(&pdev->dev, "cannot get clock\n");
768		ret = PTR_ERR(rspi->clk);
769		goto error2;
770	}
771	clk_enable(rspi->clk);
772
773	INIT_LIST_HEAD(&rspi->queue);
 
 
 
774	spin_lock_init(&rspi->lock);
775	INIT_WORK(&rspi->ws, rspi_work);
776	init_waitqueue_head(&rspi->wait);
777
778	master->num_chipselect = 2;
779	master->bus_num = pdev->id;
780	master->setup = rspi_setup;
781	master->transfer = rspi_transfer;
782	master->cleanup = rspi_cleanup;
 
 
 
 
 
 
 
783
784	ret = request_irq(irq, rspi_irq, 0, dev_name(&pdev->dev), rspi);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
785	if (ret < 0) {
786		dev_err(&pdev->dev, "request_irq error\n");
787		goto error3;
788	}
789
790	rspi->irq = irq;
791	rspi_request_dma(rspi, pdev);
 
792
793	ret = spi_register_master(master);
794	if (ret < 0) {
795		dev_err(&pdev->dev, "spi_register_master error.\n");
796		goto error4;
797	}
798
799	dev_info(&pdev->dev, "probed\n");
800
801	return 0;
802
803error4:
804	rspi_release_dma(rspi);
805	free_irq(irq, rspi);
806error3:
807	clk_put(rspi->clk);
808error2:
809	iounmap(rspi->addr);
810error1:
811	spi_master_put(master);
812
813	return ret;
814}
815
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
816static struct platform_driver rspi_driver = {
817	.probe =	rspi_probe,
818	.remove =	__devexit_p(rspi_remove),
 
819	.driver		= {
820		.name = "rspi",
821		.owner	= THIS_MODULE,
 
822	},
823};
824module_platform_driver(rspi_driver);
825
826MODULE_DESCRIPTION("Renesas RSPI bus driver");
827MODULE_LICENSE("GPL v2");
828MODULE_AUTHOR("Yoshihiro Shimoda");
829MODULE_ALIAS("platform:rspi");