1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
   4 *
   5 * Copyright (C) 2008-2012 ST-Ericsson AB
   6 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
   7 *
   8 * Author: Linus Walleij <linus.walleij@stericsson.com>
   9 *
  10 * Initial version inspired by:
  11 *	linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
  12 * Initial adoption to PL022 by:
  13 *      Sachin Verma <sachin.verma@st.com>
 
 
 
 
 
 
 
 
 
 
  14 */
  15
  16#include <linux/init.h>
  17#include <linux/module.h>
  18#include <linux/device.h>
  19#include <linux/ioport.h>
  20#include <linux/errno.h>
  21#include <linux/interrupt.h>
  22#include <linux/spi/spi.h>
  23#include <linux/delay.h>
  24#include <linux/clk.h>
  25#include <linux/err.h>
  26#include <linux/amba/bus.h>
  27#include <linux/amba/pl022.h>
  28#include <linux/io.h>
  29#include <linux/slab.h>
  30#include <linux/dmaengine.h>
  31#include <linux/dma-mapping.h>
  32#include <linux/scatterlist.h>
  33#include <linux/pm_runtime.h>
  34#include <linux/of.h>
 
  35#include <linux/pinctrl/consumer.h>
  36
  37/*
  38 * This macro is used to define some register default values.
  39 * reg is masked with mask, the OR:ed with an (again masked)
  40 * val shifted sb steps to the left.
  41 */
  42#define SSP_WRITE_BITS(reg, val, mask, sb) \
  43 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
  44
  45/*
  46 * This macro is also used to define some default values.
  47 * It will just shift val by sb steps to the left and mask
  48 * the result with mask.
  49 */
  50#define GEN_MASK_BITS(val, mask, sb) \
  51 (((val)<<(sb)) & (mask))
  52
  53#define DRIVE_TX		0
  54#define DO_NOT_DRIVE_TX		1
  55
  56#define DO_NOT_QUEUE_DMA	0
  57#define QUEUE_DMA		1
  58
  59#define RX_TRANSFER		1
  60#define TX_TRANSFER		2
  61
  62/*
  63 * Macros to access SSP Registers with their offsets
  64 */
  65#define SSP_CR0(r)	(r + 0x000)
  66#define SSP_CR1(r)	(r + 0x004)
  67#define SSP_DR(r)	(r + 0x008)
  68#define SSP_SR(r)	(r + 0x00C)
  69#define SSP_CPSR(r)	(r + 0x010)
  70#define SSP_IMSC(r)	(r + 0x014)
  71#define SSP_RIS(r)	(r + 0x018)
  72#define SSP_MIS(r)	(r + 0x01C)
  73#define SSP_ICR(r)	(r + 0x020)
  74#define SSP_DMACR(r)	(r + 0x024)
  75#define SSP_CSR(r)	(r + 0x030) /* vendor extension */
  76#define SSP_ITCR(r)	(r + 0x080)
  77#define SSP_ITIP(r)	(r + 0x084)
  78#define SSP_ITOP(r)	(r + 0x088)
  79#define SSP_TDR(r)	(r + 0x08C)
  80
  81#define SSP_PID0(r)	(r + 0xFE0)
  82#define SSP_PID1(r)	(r + 0xFE4)
  83#define SSP_PID2(r)	(r + 0xFE8)
  84#define SSP_PID3(r)	(r + 0xFEC)
  85
  86#define SSP_CID0(r)	(r + 0xFF0)
  87#define SSP_CID1(r)	(r + 0xFF4)
  88#define SSP_CID2(r)	(r + 0xFF8)
  89#define SSP_CID3(r)	(r + 0xFFC)
  90
  91/*
  92 * SSP Control Register 0  - SSP_CR0
  93 */
  94#define SSP_CR0_MASK_DSS	(0x0FUL << 0)
  95#define SSP_CR0_MASK_FRF	(0x3UL << 4)
  96#define SSP_CR0_MASK_SPO	(0x1UL << 6)
  97#define SSP_CR0_MASK_SPH	(0x1UL << 7)
  98#define SSP_CR0_MASK_SCR	(0xFFUL << 8)
  99
 100/*
 101 * The ST version of this block moves som bits
 102 * in SSP_CR0 and extends it to 32 bits
 103 */
 104#define SSP_CR0_MASK_DSS_ST	(0x1FUL << 0)
 105#define SSP_CR0_MASK_HALFDUP_ST	(0x1UL << 5)
 106#define SSP_CR0_MASK_CSS_ST	(0x1FUL << 16)
 107#define SSP_CR0_MASK_FRF_ST	(0x3UL << 21)
 108
 109/*
 110 * SSP Control Register 0  - SSP_CR1
 111 */
 112#define SSP_CR1_MASK_LBM	(0x1UL << 0)
 113#define SSP_CR1_MASK_SSE	(0x1UL << 1)
 114#define SSP_CR1_MASK_MS		(0x1UL << 2)
 115#define SSP_CR1_MASK_SOD	(0x1UL << 3)
 116
 117/*
 118 * The ST version of this block adds some bits
 119 * in SSP_CR1
 120 */
 121#define SSP_CR1_MASK_RENDN_ST	(0x1UL << 4)
 122#define SSP_CR1_MASK_TENDN_ST	(0x1UL << 5)
 123#define SSP_CR1_MASK_MWAIT_ST	(0x1UL << 6)
 124#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
 125#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
 126/* This one is only in the PL023 variant */
 127#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
 128
 129/*
 130 * SSP Status Register - SSP_SR
 131 */
 132#define SSP_SR_MASK_TFE		(0x1UL << 0) /* Transmit FIFO empty */
 133#define SSP_SR_MASK_TNF		(0x1UL << 1) /* Transmit FIFO not full */
 134#define SSP_SR_MASK_RNE		(0x1UL << 2) /* Receive FIFO not empty */
 135#define SSP_SR_MASK_RFF		(0x1UL << 3) /* Receive FIFO full */
 136#define SSP_SR_MASK_BSY		(0x1UL << 4) /* Busy Flag */
 137
 138/*
 139 * SSP Clock Prescale Register  - SSP_CPSR
 140 */
 141#define SSP_CPSR_MASK_CPSDVSR	(0xFFUL << 0)
 142
 143/*
 144 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
 145 */
 146#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
 147#define SSP_IMSC_MASK_RTIM  (0x1UL << 1) /* Receive timeout Interrupt mask */
 148#define SSP_IMSC_MASK_RXIM  (0x1UL << 2) /* Receive FIFO Interrupt mask */
 149#define SSP_IMSC_MASK_TXIM  (0x1UL << 3) /* Transmit FIFO Interrupt mask */
 150
 151/*
 152 * SSP Raw Interrupt Status Register - SSP_RIS
 153 */
 154/* Receive Overrun Raw Interrupt status */
 155#define SSP_RIS_MASK_RORRIS		(0x1UL << 0)
 156/* Receive Timeout Raw Interrupt status */
 157#define SSP_RIS_MASK_RTRIS		(0x1UL << 1)
 158/* Receive FIFO Raw Interrupt status */
 159#define SSP_RIS_MASK_RXRIS		(0x1UL << 2)
 160/* Transmit FIFO Raw Interrupt status */
 161#define SSP_RIS_MASK_TXRIS		(0x1UL << 3)
 162
 163/*
 164 * SSP Masked Interrupt Status Register - SSP_MIS
 165 */
 166/* Receive Overrun Masked Interrupt status */
 167#define SSP_MIS_MASK_RORMIS		(0x1UL << 0)
 168/* Receive Timeout Masked Interrupt status */
 169#define SSP_MIS_MASK_RTMIS		(0x1UL << 1)
 170/* Receive FIFO Masked Interrupt status */
 171#define SSP_MIS_MASK_RXMIS		(0x1UL << 2)
 172/* Transmit FIFO Masked Interrupt status */
 173#define SSP_MIS_MASK_TXMIS		(0x1UL << 3)
 174
 175/*
 176 * SSP Interrupt Clear Register - SSP_ICR
 177 */
 178/* Receive Overrun Raw Clear Interrupt bit */
 179#define SSP_ICR_MASK_RORIC		(0x1UL << 0)
 180/* Receive Timeout Clear Interrupt bit */
 181#define SSP_ICR_MASK_RTIC		(0x1UL << 1)
 182
 183/*
 184 * SSP DMA Control Register - SSP_DMACR
 185 */
 186/* Receive DMA Enable bit */
 187#define SSP_DMACR_MASK_RXDMAE		(0x1UL << 0)
 188/* Transmit DMA Enable bit */
 189#define SSP_DMACR_MASK_TXDMAE		(0x1UL << 1)
 190
 191/*
 192 * SSP Chip Select Control Register - SSP_CSR
 193 * (vendor extension)
 194 */
 195#define SSP_CSR_CSVALUE_MASK		(0x1FUL << 0)
 196
 197/*
 198 * SSP Integration Test control Register - SSP_ITCR
 199 */
 200#define SSP_ITCR_MASK_ITEN		(0x1UL << 0)
 201#define SSP_ITCR_MASK_TESTFIFO		(0x1UL << 1)
 202
 203/*
 204 * SSP Integration Test Input Register - SSP_ITIP
 205 */
 206#define ITIP_MASK_SSPRXD		 (0x1UL << 0)
 207#define ITIP_MASK_SSPFSSIN		 (0x1UL << 1)
 208#define ITIP_MASK_SSPCLKIN		 (0x1UL << 2)
 209#define ITIP_MASK_RXDMAC		 (0x1UL << 3)
 210#define ITIP_MASK_TXDMAC		 (0x1UL << 4)
 211#define ITIP_MASK_SSPTXDIN		 (0x1UL << 5)
 212
 213/*
 214 * SSP Integration Test output Register - SSP_ITOP
 215 */
 216#define ITOP_MASK_SSPTXD		 (0x1UL << 0)
 217#define ITOP_MASK_SSPFSSOUT		 (0x1UL << 1)
 218#define ITOP_MASK_SSPCLKOUT		 (0x1UL << 2)
 219#define ITOP_MASK_SSPOEn		 (0x1UL << 3)
 220#define ITOP_MASK_SSPCTLOEn		 (0x1UL << 4)
 221#define ITOP_MASK_RORINTR		 (0x1UL << 5)
 222#define ITOP_MASK_RTINTR		 (0x1UL << 6)
 223#define ITOP_MASK_RXINTR		 (0x1UL << 7)
 224#define ITOP_MASK_TXINTR		 (0x1UL << 8)
 225#define ITOP_MASK_INTR			 (0x1UL << 9)
 226#define ITOP_MASK_RXDMABREQ		 (0x1UL << 10)
 227#define ITOP_MASK_RXDMASREQ		 (0x1UL << 11)
 228#define ITOP_MASK_TXDMABREQ		 (0x1UL << 12)
 229#define ITOP_MASK_TXDMASREQ		 (0x1UL << 13)
 230
 231/*
 232 * SSP Test Data Register - SSP_TDR
 233 */
 234#define TDR_MASK_TESTDATA		(0xFFFFFFFF)
 235
 236/*
 237 * Message State
 238 * we use the spi_message.state (void *) pointer to
 239 * hold a single state value, that's why all this
 240 * (void *) casting is done here.
 241 */
 242#define STATE_START			((void *) 0)
 243#define STATE_RUNNING			((void *) 1)
 244#define STATE_DONE			((void *) 2)
 245#define STATE_ERROR			((void *) -1)
 246#define STATE_TIMEOUT			((void *) -2)
 247
 248/*
 249 * SSP State - Whether Enabled or Disabled
 250 */
 251#define SSP_DISABLED			(0)
 252#define SSP_ENABLED			(1)
 253
 254/*
 255 * SSP DMA State - Whether DMA Enabled or Disabled
 256 */
 257#define SSP_DMA_DISABLED		(0)
 258#define SSP_DMA_ENABLED			(1)
 259
 260/*
 261 * SSP Clock Defaults
 262 */
 263#define SSP_DEFAULT_CLKRATE 0x2
 264#define SSP_DEFAULT_PRESCALE 0x40
 265
 266/*
 267 * SSP Clock Parameter ranges
 268 */
 269#define CPSDVR_MIN 0x02
 270#define CPSDVR_MAX 0xFE
 271#define SCR_MIN 0x00
 272#define SCR_MAX 0xFF
 273
 274/*
 275 * SSP Interrupt related Macros
 276 */
 277#define DEFAULT_SSP_REG_IMSC  0x0UL
 278#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
 279#define ENABLE_ALL_INTERRUPTS ( \
 280	SSP_IMSC_MASK_RORIM | \
 281	SSP_IMSC_MASK_RTIM | \
 282	SSP_IMSC_MASK_RXIM | \
 283	SSP_IMSC_MASK_TXIM \
 284)
 285
 286#define CLEAR_ALL_INTERRUPTS  0x3
 287
 288#define SPI_POLLING_TIMEOUT 1000
 289
 290/*
 291 * The type of reading going on this chip
 292 */
 293enum ssp_reading {
 294	READING_NULL,
 295	READING_U8,
 296	READING_U16,
 297	READING_U32
 298};
 299
 300/*
 301 * The type of writing going on this chip
 302 */
 303enum ssp_writing {
 304	WRITING_NULL,
 305	WRITING_U8,
 306	WRITING_U16,
 307	WRITING_U32
 308};
 309
 310/**
 311 * struct vendor_data - vendor-specific config parameters
 312 * for PL022 derivates
 313 * @fifodepth: depth of FIFOs (both)
 314 * @max_bpw: maximum number of bits per word
 315 * @unidir: supports unidirection transfers
 316 * @extended_cr: 32 bit wide control register 0 with extra
 317 * features and extra features in CR1 as found in the ST variants
 318 * @pl023: supports a subset of the ST extensions called "PL023"
 319 * @loopback: supports loopback mode
 320 * @internal_cs_ctrl: supports chip select control register
 321 */
 322struct vendor_data {
 323	int fifodepth;
 324	int max_bpw;
 325	bool unidir;
 326	bool extended_cr;
 327	bool pl023;
 328	bool loopback;
 329	bool internal_cs_ctrl;
 330};
 331
 332/**
 333 * struct pl022 - This is the private SSP driver data structure
 334 * @adev: AMBA device model hookup
 335 * @vendor: vendor data for the IP block
 336 * @phybase: the physical memory where the SSP device resides
 337 * @virtbase: the virtual memory where the SSP is mapped
 338 * @clk: outgoing clock "SPICLK" for the SPI bus
 339 * @host: SPI framework hookup
 340 * @host_info: controller-specific data from machine setup
 
 
 
 
 
 
 
 
 
 341 * @cur_transfer: Pointer to current spi_transfer
 342 * @cur_chip: pointer to current clients chip(assigned from controller_state)
 
 
 
 
 343 * @tx: current position in TX buffer to be read
 344 * @tx_end: end position in TX buffer to be read
 345 * @rx: current position in RX buffer to be written
 346 * @rx_end: end position in RX buffer to be written
 347 * @read: the type of read currently going on
 348 * @write: the type of write currently going on
 349 * @exp_fifo_level: expected FIFO level
 350 * @rx_lev_trig: receive FIFO watermark level which triggers IRQ
 351 * @tx_lev_trig: transmit FIFO watermark level which triggers IRQ
 352 * @dma_rx_channel: optional channel for RX DMA
 353 * @dma_tx_channel: optional channel for TX DMA
 354 * @sgt_rx: scattertable for the RX transfer
 355 * @sgt_tx: scattertable for the TX transfer
 356 * @dummypage: a dummy page used for driving data on the bus with DMA
 357 * @dma_running: indicates whether DMA is in operation
 358 * @cur_cs: current chip select index
 359 */
 360struct pl022 {
 361	struct amba_device		*adev;
 362	struct vendor_data		*vendor;
 363	resource_size_t			phybase;
 364	void __iomem			*virtbase;
 365	struct clk			*clk;
 366	struct spi_controller		*host;
 367	struct pl022_ssp_controller	*host_info;
 
 
 
 368	struct spi_transfer		*cur_transfer;
 369	struct chip_data		*cur_chip;
 
 370	void				*tx;
 371	void				*tx_end;
 372	void				*rx;
 373	void				*rx_end;
 374	enum ssp_reading		read;
 375	enum ssp_writing		write;
 376	u32				exp_fifo_level;
 377	enum ssp_rx_level_trig		rx_lev_trig;
 378	enum ssp_tx_level_trig		tx_lev_trig;
 379	/* DMA settings */
 380#ifdef CONFIG_DMA_ENGINE
 381	struct dma_chan			*dma_rx_channel;
 382	struct dma_chan			*dma_tx_channel;
 383	struct sg_table			sgt_rx;
 384	struct sg_table			sgt_tx;
 385	char				*dummypage;
 386	bool				dma_running;
 387#endif
 388	int cur_cs;
 
 389};
 390
 391/**
 392 * struct chip_data - To maintain runtime state of SSP for each client chip
 393 * @cr0: Value of control register CR0 of SSP - on later ST variants this
 394 *       register is 32 bits wide rather than just 16
 395 * @cr1: Value of control register CR1 of SSP
 396 * @dmacr: Value of DMA control Register of SSP
 397 * @cpsr: Value of Clock prescale register
 398 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
 399 * @enable_dma: Whether to enable DMA or not
 400 * @read: function ptr to be used to read when doing xfer for this chip
 401 * @write: function ptr to be used to write when doing xfer for this chip
 
 402 * @xfer_type: polling/interrupt/DMA
 403 *
 404 * Runtime state of the SSP controller, maintained per chip,
 405 * This would be set according to the current message that would be served
 406 */
 407struct chip_data {
 408	u32 cr0;
 409	u16 cr1;
 410	u16 dmacr;
 411	u16 cpsr;
 412	u8 n_bytes;
 413	bool enable_dma;
 414	enum ssp_reading read;
 415	enum ssp_writing write;
 
 416	int xfer_type;
 417};
 418
 419/**
 420 * internal_cs_control - Control chip select signals via SSP_CSR.
 421 * @pl022: SSP driver private data structure
 422 * @enable: select/delect the chip
 423 *
 424 * Used on controller with internal chip select control via SSP_CSR register
 425 * (vendor extension). Each of the 5 LSB in the register controls one chip
 426 * select signal.
 427 */
 428static void internal_cs_control(struct pl022 *pl022, bool enable)
 429{
 430	u32 tmp;
 
 431
 432	tmp = readw(SSP_CSR(pl022->virtbase));
 433	if (enable)
 434		tmp &= ~BIT(pl022->cur_cs);
 
 435	else
 436		tmp |= BIT(pl022->cur_cs);
 437	writew(tmp, SSP_CSR(pl022->virtbase));
 438}
 439
 440static void pl022_cs_control(struct spi_device *spi, bool enable)
 
 
 
 
 
 
 441{
 442	struct pl022 *pl022 = spi_controller_get_devdata(spi->controller);
 443	if (pl022->vendor->internal_cs_ctrl)
 444		internal_cs_control(pl022, enable);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 445}
 446
 447/**
 448 * flush - flush the FIFO to reach a clean state
 449 * @pl022: SSP driver private data structure
 450 */
 451static int flush(struct pl022 *pl022)
 452{
 453	unsigned long limit = loops_per_jiffy << 1;
 454
 455	dev_dbg(&pl022->adev->dev, "flush\n");
 456	do {
 457		while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
 458			readw(SSP_DR(pl022->virtbase));
 459	} while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
 460
 461	pl022->exp_fifo_level = 0;
 462
 463	return limit;
 464}
 465
 466/**
 467 * restore_state - Load configuration of current chip
 468 * @pl022: SSP driver private data structure
 469 */
 470static void restore_state(struct pl022 *pl022)
 471{
 472	struct chip_data *chip = pl022->cur_chip;
 473
 474	if (pl022->vendor->extended_cr)
 475		writel(chip->cr0, SSP_CR0(pl022->virtbase));
 476	else
 477		writew(chip->cr0, SSP_CR0(pl022->virtbase));
 478	writew(chip->cr1, SSP_CR1(pl022->virtbase));
 479	writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
 480	writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
 481	writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
 482	writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
 483}
 484
 485/*
 486 * Default SSP Register Values
 487 */
 488#define DEFAULT_SSP_REG_CR0 ( \
 489	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0)	| \
 490	GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
 491	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
 492	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
 493	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
 494)
 495
 496/* ST versions have slightly different bit layout */
 497#define DEFAULT_SSP_REG_CR0_ST ( \
 498	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0)	| \
 499	GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
 500	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
 501	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
 502	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
 503	GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16)	| \
 504	GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
 505)
 506
 507/* The PL023 version is slightly different again */
 508#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
 509	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0)	| \
 510	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
 511	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
 512	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
 513)
 514
 515#define DEFAULT_SSP_REG_CR1 ( \
 516	GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
 517	GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
 518	GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
 519	GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
 520)
 521
 522/* ST versions extend this register to use all 16 bits */
 523#define DEFAULT_SSP_REG_CR1_ST ( \
 524	DEFAULT_SSP_REG_CR1 | \
 525	GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
 526	GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
 527	GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
 528	GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
 529	GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
 530)
 531
 532/*
 533 * The PL023 variant has further differences: no loopback mode, no microwire
 534 * support, and a new clock feedback delay setting.
 535 */
 536#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
 537	GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
 538	GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
 539	GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
 540	GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
 541	GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
 542	GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
 543	GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
 544	GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
 545)
 546
 547#define DEFAULT_SSP_REG_CPSR ( \
 548	GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
 549)
 550
 551#define DEFAULT_SSP_REG_DMACR (\
 552	GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
 553	GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
 554)
 555
 556/**
 557 * load_ssp_default_config - Load default configuration for SSP
 558 * @pl022: SSP driver private data structure
 559 */
 560static void load_ssp_default_config(struct pl022 *pl022)
 561{
 562	if (pl022->vendor->pl023) {
 563		writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
 564		writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
 565	} else if (pl022->vendor->extended_cr) {
 566		writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
 567		writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
 568	} else {
 569		writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
 570		writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
 571	}
 572	writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
 573	writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
 574	writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
 575	writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
 576}
 577
 578/*
 579 * This will write to TX and read from RX according to the parameters
 580 * set in pl022.
 581 */
 582static void readwriter(struct pl022 *pl022)
 583{
 584
 585	/*
 586	 * The FIFO depth is different between primecell variants.
 587	 * I believe filling in too much in the FIFO might cause
 588	 * errons in 8bit wide transfers on ARM variants (just 8 words
 589	 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
 590	 *
 591	 * To prevent this issue, the TX FIFO is only filled to the
 592	 * unused RX FIFO fill length, regardless of what the TX
 593	 * FIFO status flag indicates.
 594	 */
 595	dev_dbg(&pl022->adev->dev,
 596		"%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
 597		__func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
 598
 599	/* Read as much as you can */
 600	while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
 601	       && (pl022->rx < pl022->rx_end)) {
 602		switch (pl022->read) {
 603		case READING_NULL:
 604			readw(SSP_DR(pl022->virtbase));
 605			break;
 606		case READING_U8:
 607			*(u8 *) (pl022->rx) =
 608				readw(SSP_DR(pl022->virtbase)) & 0xFFU;
 609			break;
 610		case READING_U16:
 611			*(u16 *) (pl022->rx) =
 612				(u16) readw(SSP_DR(pl022->virtbase));
 613			break;
 614		case READING_U32:
 615			*(u32 *) (pl022->rx) =
 616				readl(SSP_DR(pl022->virtbase));
 617			break;
 618		}
 619		pl022->rx += (pl022->cur_chip->n_bytes);
 620		pl022->exp_fifo_level--;
 621	}
 622	/*
 623	 * Write as much as possible up to the RX FIFO size
 624	 */
 625	while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
 626	       && (pl022->tx < pl022->tx_end)) {
 627		switch (pl022->write) {
 628		case WRITING_NULL:
 629			writew(0x0, SSP_DR(pl022->virtbase));
 630			break;
 631		case WRITING_U8:
 632			writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
 633			break;
 634		case WRITING_U16:
 635			writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
 636			break;
 637		case WRITING_U32:
 638			writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
 639			break;
 640		}
 641		pl022->tx += (pl022->cur_chip->n_bytes);
 642		pl022->exp_fifo_level++;
 643		/*
 644		 * This inner reader takes care of things appearing in the RX
 645		 * FIFO as we're transmitting. This will happen a lot since the
 646		 * clock starts running when you put things into the TX FIFO,
 647		 * and then things are continuously clocked into the RX FIFO.
 648		 */
 649		while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
 650		       && (pl022->rx < pl022->rx_end)) {
 651			switch (pl022->read) {
 652			case READING_NULL:
 653				readw(SSP_DR(pl022->virtbase));
 654				break;
 655			case READING_U8:
 656				*(u8 *) (pl022->rx) =
 657					readw(SSP_DR(pl022->virtbase)) & 0xFFU;
 658				break;
 659			case READING_U16:
 660				*(u16 *) (pl022->rx) =
 661					(u16) readw(SSP_DR(pl022->virtbase));
 662				break;
 663			case READING_U32:
 664				*(u32 *) (pl022->rx) =
 665					readl(SSP_DR(pl022->virtbase));
 666				break;
 667			}
 668			pl022->rx += (pl022->cur_chip->n_bytes);
 669			pl022->exp_fifo_level--;
 670		}
 671	}
 672	/*
 673	 * When we exit here the TX FIFO should be full and the RX FIFO
 674	 * should be empty
 675	 */
 676}
 677
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 678/*
 679 * This DMA functionality is only compiled in if we have
 680 * access to the generic DMA devices/DMA engine.
 681 */
 682#ifdef CONFIG_DMA_ENGINE
 683static void unmap_free_dma_scatter(struct pl022 *pl022)
 684{
 685	/* Unmap and free the SG tables */
 686	dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
 687		     pl022->sgt_tx.nents, DMA_TO_DEVICE);
 688	dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
 689		     pl022->sgt_rx.nents, DMA_FROM_DEVICE);
 690	sg_free_table(&pl022->sgt_rx);
 691	sg_free_table(&pl022->sgt_tx);
 692}
 693
 694static void dma_callback(void *data)
 695{
 696	struct pl022 *pl022 = data;
 
 697
 698	BUG_ON(!pl022->sgt_rx.sgl);
 699
 700#ifdef VERBOSE_DEBUG
 701	/*
 702	 * Optionally dump out buffers to inspect contents, this is
 703	 * good if you want to convince yourself that the loopback
 704	 * read/write contents are the same, when adopting to a new
 705	 * DMA engine.
 706	 */
 707	{
 708		struct scatterlist *sg;
 709		unsigned int i;
 710
 711		dma_sync_sg_for_cpu(&pl022->adev->dev,
 712				    pl022->sgt_rx.sgl,
 713				    pl022->sgt_rx.nents,
 714				    DMA_FROM_DEVICE);
 715
 716		for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
 717			dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
 718			print_hex_dump(KERN_ERR, "SPI RX: ",
 719				       DUMP_PREFIX_OFFSET,
 720				       16,
 721				       1,
 722				       sg_virt(sg),
 723				       sg_dma_len(sg),
 724				       1);
 725		}
 726		for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
 727			dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
 728			print_hex_dump(KERN_ERR, "SPI TX: ",
 729				       DUMP_PREFIX_OFFSET,
 730				       16,
 731				       1,
 732				       sg_virt(sg),
 733				       sg_dma_len(sg),
 734				       1);
 735		}
 736	}
 737#endif
 738
 739	unmap_free_dma_scatter(pl022);
 740
 741	spi_finalize_current_transfer(pl022->host);
 
 
 
 
 
 
 
 742}
 743
 744static void setup_dma_scatter(struct pl022 *pl022,
 745			      void *buffer,
 746			      unsigned int length,
 747			      struct sg_table *sgtab)
 748{
 749	struct scatterlist *sg;
 750	int bytesleft = length;
 751	void *bufp = buffer;
 752	int mapbytes;
 753	int i;
 754
 755	if (buffer) {
 756		for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
 757			/*
 758			 * If there are less bytes left than what fits
 759			 * in the current page (plus page alignment offset)
 760			 * we just feed in this, else we stuff in as much
 761			 * as we can.
 762			 */
 763			if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
 764				mapbytes = bytesleft;
 765			else
 766				mapbytes = PAGE_SIZE - offset_in_page(bufp);
 767			sg_set_page(sg, virt_to_page(bufp),
 768				    mapbytes, offset_in_page(bufp));
 769			bufp += mapbytes;
 770			bytesleft -= mapbytes;
 771			dev_dbg(&pl022->adev->dev,
 772				"set RX/TX target page @ %p, %d bytes, %d left\n",
 773				bufp, mapbytes, bytesleft);
 774		}
 775	} else {
 776		/* Map the dummy buffer on every page */
 777		for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
 778			if (bytesleft < PAGE_SIZE)
 779				mapbytes = bytesleft;
 780			else
 781				mapbytes = PAGE_SIZE;
 782			sg_set_page(sg, virt_to_page(pl022->dummypage),
 783				    mapbytes, 0);
 784			bytesleft -= mapbytes;
 785			dev_dbg(&pl022->adev->dev,
 786				"set RX/TX to dummy page %d bytes, %d left\n",
 787				mapbytes, bytesleft);
 788
 789		}
 790	}
 791	BUG_ON(bytesleft);
 792}
 793
 794/**
 795 * configure_dma - configures the channels for the next transfer
 796 * @pl022: SSP driver's private data structure
 797 */
 798static int configure_dma(struct pl022 *pl022)
 799{
 800	struct dma_slave_config rx_conf = {
 801		.src_addr = SSP_DR(pl022->phybase),
 802		.direction = DMA_DEV_TO_MEM,
 803		.device_fc = false,
 804	};
 805	struct dma_slave_config tx_conf = {
 806		.dst_addr = SSP_DR(pl022->phybase),
 807		.direction = DMA_MEM_TO_DEV,
 808		.device_fc = false,
 809	};
 810	unsigned int pages;
 811	int ret;
 812	int rx_sglen, tx_sglen;
 813	struct dma_chan *rxchan = pl022->dma_rx_channel;
 814	struct dma_chan *txchan = pl022->dma_tx_channel;
 815	struct dma_async_tx_descriptor *rxdesc;
 816	struct dma_async_tx_descriptor *txdesc;
 817
 818	/* Check that the channels are available */
 819	if (!rxchan || !txchan)
 820		return -ENODEV;
 821
 822	/*
 823	 * If supplied, the DMA burstsize should equal the FIFO trigger level.
 824	 * Notice that the DMA engine uses one-to-one mapping. Since we can
 825	 * not trigger on 2 elements this needs explicit mapping rather than
 826	 * calculation.
 827	 */
 828	switch (pl022->rx_lev_trig) {
 829	case SSP_RX_1_OR_MORE_ELEM:
 830		rx_conf.src_maxburst = 1;
 831		break;
 832	case SSP_RX_4_OR_MORE_ELEM:
 833		rx_conf.src_maxburst = 4;
 834		break;
 835	case SSP_RX_8_OR_MORE_ELEM:
 836		rx_conf.src_maxburst = 8;
 837		break;
 838	case SSP_RX_16_OR_MORE_ELEM:
 839		rx_conf.src_maxburst = 16;
 840		break;
 841	case SSP_RX_32_OR_MORE_ELEM:
 842		rx_conf.src_maxburst = 32;
 843		break;
 844	default:
 845		rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
 846		break;
 847	}
 848
 849	switch (pl022->tx_lev_trig) {
 850	case SSP_TX_1_OR_MORE_EMPTY_LOC:
 851		tx_conf.dst_maxburst = 1;
 852		break;
 853	case SSP_TX_4_OR_MORE_EMPTY_LOC:
 854		tx_conf.dst_maxburst = 4;
 855		break;
 856	case SSP_TX_8_OR_MORE_EMPTY_LOC:
 857		tx_conf.dst_maxburst = 8;
 858		break;
 859	case SSP_TX_16_OR_MORE_EMPTY_LOC:
 860		tx_conf.dst_maxburst = 16;
 861		break;
 862	case SSP_TX_32_OR_MORE_EMPTY_LOC:
 863		tx_conf.dst_maxburst = 32;
 864		break;
 865	default:
 866		tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
 867		break;
 868	}
 869
 870	switch (pl022->read) {
 871	case READING_NULL:
 872		/* Use the same as for writing */
 873		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 874		break;
 875	case READING_U8:
 876		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 877		break;
 878	case READING_U16:
 879		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 880		break;
 881	case READING_U32:
 882		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 883		break;
 884	}
 885
 886	switch (pl022->write) {
 887	case WRITING_NULL:
 888		/* Use the same as for reading */
 889		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 890		break;
 891	case WRITING_U8:
 892		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 893		break;
 894	case WRITING_U16:
 895		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 896		break;
 897	case WRITING_U32:
 898		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 899		break;
 900	}
 901
 902	/* SPI pecularity: we need to read and write the same width */
 903	if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
 904		rx_conf.src_addr_width = tx_conf.dst_addr_width;
 905	if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
 906		tx_conf.dst_addr_width = rx_conf.src_addr_width;
 907	BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
 908
 909	dmaengine_slave_config(rxchan, &rx_conf);
 910	dmaengine_slave_config(txchan, &tx_conf);
 911
 912	/* Create sglists for the transfers */
 913	pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
 914	dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
 915
 916	ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
 917	if (ret)
 918		goto err_alloc_rx_sg;
 919
 920	ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
 921	if (ret)
 922		goto err_alloc_tx_sg;
 923
 924	/* Fill in the scatterlists for the RX+TX buffers */
 925	setup_dma_scatter(pl022, pl022->rx,
 926			  pl022->cur_transfer->len, &pl022->sgt_rx);
 927	setup_dma_scatter(pl022, pl022->tx,
 928			  pl022->cur_transfer->len, &pl022->sgt_tx);
 929
 930	/* Map DMA buffers */
 931	rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
 932			   pl022->sgt_rx.nents, DMA_FROM_DEVICE);
 933	if (!rx_sglen)
 934		goto err_rx_sgmap;
 935
 936	tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
 937			   pl022->sgt_tx.nents, DMA_TO_DEVICE);
 938	if (!tx_sglen)
 939		goto err_tx_sgmap;
 940
 941	/* Send both scatterlists */
 942	rxdesc = dmaengine_prep_slave_sg(rxchan,
 943				      pl022->sgt_rx.sgl,
 944				      rx_sglen,
 945				      DMA_DEV_TO_MEM,
 946				      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 947	if (!rxdesc)
 948		goto err_rxdesc;
 949
 950	txdesc = dmaengine_prep_slave_sg(txchan,
 951				      pl022->sgt_tx.sgl,
 952				      tx_sglen,
 953				      DMA_MEM_TO_DEV,
 954				      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 955	if (!txdesc)
 956		goto err_txdesc;
 957
 958	/* Put the callback on the RX transfer only, that should finish last */
 959	rxdesc->callback = dma_callback;
 960	rxdesc->callback_param = pl022;
 961
 962	/* Submit and fire RX and TX with TX last so we're ready to read! */
 963	dmaengine_submit(rxdesc);
 964	dmaengine_submit(txdesc);
 965	dma_async_issue_pending(rxchan);
 966	dma_async_issue_pending(txchan);
 967	pl022->dma_running = true;
 968
 969	return 0;
 970
 971err_txdesc:
 972	dmaengine_terminate_all(txchan);
 973err_rxdesc:
 974	dmaengine_terminate_all(rxchan);
 975	dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
 976		     pl022->sgt_tx.nents, DMA_TO_DEVICE);
 977err_tx_sgmap:
 978	dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
 979		     pl022->sgt_rx.nents, DMA_FROM_DEVICE);
 980err_rx_sgmap:
 981	sg_free_table(&pl022->sgt_tx);
 982err_alloc_tx_sg:
 983	sg_free_table(&pl022->sgt_rx);
 984err_alloc_rx_sg:
 985	return -ENOMEM;
 986}
 987
 988static int pl022_dma_probe(struct pl022 *pl022)
 989{
 990	dma_cap_mask_t mask;
 991
 992	/* Try to acquire a generic DMA engine slave channel */
 993	dma_cap_zero(mask);
 994	dma_cap_set(DMA_SLAVE, mask);
 995	/*
 996	 * We need both RX and TX channels to do DMA, else do none
 997	 * of them.
 998	 */
 999	pl022->dma_rx_channel = dma_request_channel(mask,
1000					    pl022->host_info->dma_filter,
1001					    pl022->host_info->dma_rx_param);
1002	if (!pl022->dma_rx_channel) {
1003		dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1004		goto err_no_rxchan;
1005	}
1006
1007	pl022->dma_tx_channel = dma_request_channel(mask,
1008					    pl022->host_info->dma_filter,
1009					    pl022->host_info->dma_tx_param);
1010	if (!pl022->dma_tx_channel) {
1011		dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1012		goto err_no_txchan;
1013	}
1014
1015	pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1016	if (!pl022->dummypage)
 
1017		goto err_no_dummypage;
 
1018
1019	dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1020		 dma_chan_name(pl022->dma_rx_channel),
1021		 dma_chan_name(pl022->dma_tx_channel));
1022
1023	return 0;
1024
1025err_no_dummypage:
1026	dma_release_channel(pl022->dma_tx_channel);
1027err_no_txchan:
1028	dma_release_channel(pl022->dma_rx_channel);
1029	pl022->dma_rx_channel = NULL;
1030err_no_rxchan:
1031	dev_err(&pl022->adev->dev,
1032			"Failed to work in dma mode, work without dma!\n");
1033	return -ENODEV;
1034}
1035
1036static int pl022_dma_autoprobe(struct pl022 *pl022)
1037{
1038	struct device *dev = &pl022->adev->dev;
1039	struct dma_chan *chan;
1040	int err;
1041
1042	/* automatically configure DMA channels from platform, normally using DT */
1043	chan = dma_request_chan(dev, "rx");
1044	if (IS_ERR(chan)) {
1045		err = PTR_ERR(chan);
1046		goto err_no_rxchan;
1047	}
1048
1049	pl022->dma_rx_channel = chan;
1050
1051	chan = dma_request_chan(dev, "tx");
1052	if (IS_ERR(chan)) {
1053		err = PTR_ERR(chan);
1054		goto err_no_txchan;
1055	}
1056
1057	pl022->dma_tx_channel = chan;
1058
1059	pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1060	if (!pl022->dummypage) {
1061		err = -ENOMEM;
1062		goto err_no_dummypage;
1063	}
1064
1065	return 0;
1066
1067err_no_dummypage:
1068	dma_release_channel(pl022->dma_tx_channel);
1069	pl022->dma_tx_channel = NULL;
1070err_no_txchan:
1071	dma_release_channel(pl022->dma_rx_channel);
1072	pl022->dma_rx_channel = NULL;
1073err_no_rxchan:
1074	return err;
1075}
1076
1077static void terminate_dma(struct pl022 *pl022)
1078{
1079	if (!pl022->dma_running)
1080		return;
1081
1082	struct dma_chan *rxchan = pl022->dma_rx_channel;
1083	struct dma_chan *txchan = pl022->dma_tx_channel;
1084
1085	dmaengine_terminate_all(rxchan);
1086	dmaengine_terminate_all(txchan);
1087	unmap_free_dma_scatter(pl022);
1088	pl022->dma_running = false;
1089}
1090
1091static void pl022_dma_remove(struct pl022 *pl022)
1092{
1093	terminate_dma(pl022);
 
1094	if (pl022->dma_tx_channel)
1095		dma_release_channel(pl022->dma_tx_channel);
1096	if (pl022->dma_rx_channel)
1097		dma_release_channel(pl022->dma_rx_channel);
1098	kfree(pl022->dummypage);
1099}
1100
1101#else
1102static inline int configure_dma(struct pl022 *pl022)
1103{
1104	return -ENODEV;
1105}
1106
1107static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1108{
1109	return 0;
1110}
1111
1112static inline int pl022_dma_probe(struct pl022 *pl022)
1113{
1114	return 0;
1115}
1116
1117static inline void terminate_dma(struct pl022 *pl022)
1118{
1119}
1120
1121static inline void pl022_dma_remove(struct pl022 *pl022)
1122{
1123}
1124#endif
1125
1126/**
1127 * pl022_interrupt_handler - Interrupt handler for SSP controller
1128 * @irq: IRQ number
1129 * @dev_id: Local device data
1130 *
1131 * This function handles interrupts generated for an interrupt based transfer.
1132 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1133 * current message's state as STATE_ERROR and schedule the tasklet
1134 * pump_transfers which will do the postprocessing of the current message by
1135 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1136 * more data, and writes data in TX FIFO till it is not full. If we complete
1137 * the transfer we move to the next transfer and schedule the tasklet.
1138 */
1139static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1140{
1141	struct pl022 *pl022 = dev_id;
 
1142	u16 irq_status = 0;
 
 
 
 
 
 
 
 
 
1143	/* Read the Interrupt Status Register */
1144	irq_status = readw(SSP_MIS(pl022->virtbase));
1145
1146	if (unlikely(!irq_status))
1147		return IRQ_NONE;
1148
1149	/*
1150	 * This handles the FIFO interrupts, the timeout
1151	 * interrupts are flatly ignored, they cannot be
1152	 * trusted.
1153	 */
1154	if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1155		/*
1156		 * Overrun interrupt - bail out since our Data has been
1157		 * corrupted
1158		 */
1159		dev_err(&pl022->adev->dev, "FIFO overrun\n");
1160		if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1161			dev_err(&pl022->adev->dev,
1162				"RXFIFO is full\n");
 
 
 
1163
1164		/*
1165		 * Disable and clear interrupts, disable SSP,
1166		 * mark message with bad status so it can be
1167		 * retried.
1168		 */
1169		writew(DISABLE_ALL_INTERRUPTS,
1170		       SSP_IMSC(pl022->virtbase));
1171		writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1172		writew((readw(SSP_CR1(pl022->virtbase)) &
1173			(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1174		pl022->cur_transfer->error |= SPI_TRANS_FAIL_IO;
1175		spi_finalize_current_transfer(pl022->host);
 
 
1176		return IRQ_HANDLED;
1177	}
1178
1179	readwriter(pl022);
1180
1181	if (pl022->tx == pl022->tx_end) {
 
1182		/* Disable Transmit interrupt, enable receive interrupt */
1183		writew((readw(SSP_IMSC(pl022->virtbase)) &
1184		       ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1185		       SSP_IMSC(pl022->virtbase));
1186	}
1187
1188	/*
1189	 * Since all transactions must write as much as shall be read,
1190	 * we can conclude the entire transaction once RX is complete.
1191	 * At this point, all TX will always be finished.
1192	 */
1193	if (pl022->rx >= pl022->rx_end) {
1194		writew(DISABLE_ALL_INTERRUPTS,
1195		       SSP_IMSC(pl022->virtbase));
1196		writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1197		if (unlikely(pl022->rx > pl022->rx_end)) {
1198			dev_warn(&pl022->adev->dev, "read %u surplus "
1199				 "bytes (did you request an odd "
1200				 "number of bytes on a 16bit bus?)\n",
1201				 (u32) (pl022->rx - pl022->rx_end));
1202		}
1203		spi_finalize_current_transfer(pl022->host);
 
 
 
 
 
 
1204		return IRQ_HANDLED;
1205	}
1206
1207	return IRQ_HANDLED;
1208}
1209
1210/*
1211 * This sets up the pointers to memory for the next message to
1212 * send out on the SPI bus.
1213 */
1214static int set_up_next_transfer(struct pl022 *pl022,
1215				struct spi_transfer *transfer)
1216{
1217	int residue;
1218
1219	/* Sanity check the message for this bus width */
1220	residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1221	if (unlikely(residue != 0)) {
1222		dev_err(&pl022->adev->dev,
1223			"message of %u bytes to transmit but the current "
1224			"chip bus has a data width of %u bytes!\n",
1225			pl022->cur_transfer->len,
1226			pl022->cur_chip->n_bytes);
1227		dev_err(&pl022->adev->dev, "skipping this message\n");
1228		return -EIO;
1229	}
1230	pl022->tx = (void *)transfer->tx_buf;
1231	pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1232	pl022->rx = (void *)transfer->rx_buf;
1233	pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1234	pl022->write =
1235	    pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1236	pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1237	return 0;
1238}
1239
1240static int do_interrupt_dma_transfer(struct pl022 *pl022)
 
 
 
 
 
 
1241{
1242	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1243
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1244	/*
1245	 * Default is to enable all interrupts except RX -
1246	 * this will be enabled once TX is complete
1247	 */
1248	u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
1249
1250	ret = set_up_next_transfer(pl022, pl022->cur_transfer);
1251	if (ret)
1252		return ret;
1253
 
 
 
 
 
 
 
 
 
 
 
1254	/* If we're using DMA, set up DMA here */
1255	if (pl022->cur_chip->enable_dma) {
1256		/* Configure DMA transfer */
1257		if (configure_dma(pl022)) {
1258			dev_dbg(&pl022->adev->dev,
1259				"configuration of DMA failed, fall back to interrupt mode\n");
1260			goto err_config_dma;
1261		}
1262		/* Disable interrupts in DMA mode, IRQ from DMA controller */
1263		irqflags = DISABLE_ALL_INTERRUPTS;
1264	}
1265err_config_dma:
1266	/* Enable SSP, turn on interrupts */
1267	writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1268	       SSP_CR1(pl022->virtbase));
1269	writew(irqflags, SSP_IMSC(pl022->virtbase));
1270	return 1;
1271}
1272
1273static void print_current_status(struct pl022 *pl022)
1274{
1275	u32 read_cr0;
1276	u16 read_cr1, read_dmacr, read_sr;
1277
1278	if (pl022->vendor->extended_cr)
1279		read_cr0 = readl(SSP_CR0(pl022->virtbase));
1280	else
1281		read_cr0 = readw(SSP_CR0(pl022->virtbase));
1282	read_cr1 = readw(SSP_CR1(pl022->virtbase));
1283	read_dmacr = readw(SSP_DMACR(pl022->virtbase));
1284	read_sr = readw(SSP_SR(pl022->virtbase));
1285
1286	dev_warn(&pl022->adev->dev, "spi-pl022 CR0: %x\n", read_cr0);
1287	dev_warn(&pl022->adev->dev, "spi-pl022 CR1: %x\n", read_cr1);
1288	dev_warn(&pl022->adev->dev, "spi-pl022 DMACR: %x\n", read_dmacr);
1289	dev_warn(&pl022->adev->dev, "spi-pl022 SR: %x\n", read_sr);
1290	dev_warn(&pl022->adev->dev,
1291			"spi-pl022 exp_fifo_level/fifodepth: %u/%d\n",
1292			pl022->exp_fifo_level,
1293			pl022->vendor->fifodepth);
1294
1295}
1296
1297static int do_polling_transfer(struct pl022 *pl022)
1298{
1299	int ret;
1300	unsigned long time, timeout;
1301
1302	/* Configuration Changing Per Transfer */
1303	ret = set_up_next_transfer(pl022, pl022->cur_transfer);
1304	if (ret)
1305		return ret;
1306	/* Flush FIFOs and enable SSP */
1307	flush(pl022);
1308	writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1309		SSP_CR1(pl022->virtbase));
1310
1311	dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
 
 
 
 
1312
1313	timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1314	while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1315		time = jiffies;
1316		readwriter(pl022);
1317		if (time_after(time, timeout)) {
1318			dev_warn(&pl022->adev->dev,
1319			"%s: timeout!\n", __func__);
1320			print_current_status(pl022);
1321			return -ETIMEDOUT;
 
 
 
 
 
1322		}
1323		cpu_relax();
1324	}
1325
1326	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1327}
1328
1329static int pl022_transfer_one(struct spi_controller *host, struct spi_device *spi,
1330			      struct spi_transfer *transfer)
1331{
1332	struct pl022 *pl022 = spi_controller_get_devdata(host);
1333
1334	pl022->cur_transfer = transfer;
 
 
 
 
 
1335
1336	/* Setup the SPI using the per chip configuration */
1337	pl022->cur_chip = spi_get_ctldata(spi);
1338	pl022->cur_cs = spi_get_chipselect(spi, 0);
1339
1340	restore_state(pl022);
1341	flush(pl022);
1342
1343	if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1344		return do_polling_transfer(pl022);
1345	else
1346		return do_interrupt_dma_transfer(pl022);
1347}
1348
1349static void pl022_handle_err(struct spi_controller *ctlr, struct spi_message *message)
1350{
1351	struct pl022 *pl022 = spi_controller_get_devdata(ctlr);
1352
1353	terminate_dma(pl022);
1354	writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
1355	writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1356}
1357
1358static int pl022_unprepare_transfer_hardware(struct spi_controller *host)
1359{
1360	struct pl022 *pl022 = spi_controller_get_devdata(host);
1361
1362	/* nothing more to do - disable spi/ssp and power off */
1363	writew((readw(SSP_CR1(pl022->virtbase)) &
1364		(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1365
1366	return 0;
1367}
1368
1369static int verify_controller_parameters(struct pl022 *pl022,
1370				struct pl022_config_chip const *chip_info)
1371{
1372	if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1373	    || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1374		dev_err(&pl022->adev->dev,
1375			"interface is configured incorrectly\n");
1376		return -EINVAL;
1377	}
1378	if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1379	    (!pl022->vendor->unidir)) {
1380		dev_err(&pl022->adev->dev,
1381			"unidirectional mode not supported in this "
1382			"hardware version\n");
1383		return -EINVAL;
1384	}
1385	if ((chip_info->hierarchy != SSP_MASTER)
1386	    && (chip_info->hierarchy != SSP_SLAVE)) {
1387		dev_err(&pl022->adev->dev,
1388			"hierarchy is configured incorrectly\n");
1389		return -EINVAL;
1390	}
1391	if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1392	    && (chip_info->com_mode != DMA_TRANSFER)
1393	    && (chip_info->com_mode != POLLING_TRANSFER)) {
1394		dev_err(&pl022->adev->dev,
1395			"Communication mode is configured incorrectly\n");
1396		return -EINVAL;
1397	}
1398	switch (chip_info->rx_lev_trig) {
1399	case SSP_RX_1_OR_MORE_ELEM:
1400	case SSP_RX_4_OR_MORE_ELEM:
1401	case SSP_RX_8_OR_MORE_ELEM:
1402		/* These are always OK, all variants can handle this */
1403		break;
1404	case SSP_RX_16_OR_MORE_ELEM:
1405		if (pl022->vendor->fifodepth < 16) {
1406			dev_err(&pl022->adev->dev,
1407			"RX FIFO Trigger Level is configured incorrectly\n");
1408			return -EINVAL;
1409		}
1410		break;
1411	case SSP_RX_32_OR_MORE_ELEM:
1412		if (pl022->vendor->fifodepth < 32) {
1413			dev_err(&pl022->adev->dev,
1414			"RX FIFO Trigger Level is configured incorrectly\n");
1415			return -EINVAL;
1416		}
1417		break;
1418	default:
1419		dev_err(&pl022->adev->dev,
1420			"RX FIFO Trigger Level is configured incorrectly\n");
1421		return -EINVAL;
1422	}
1423	switch (chip_info->tx_lev_trig) {
1424	case SSP_TX_1_OR_MORE_EMPTY_LOC:
1425	case SSP_TX_4_OR_MORE_EMPTY_LOC:
1426	case SSP_TX_8_OR_MORE_EMPTY_LOC:
1427		/* These are always OK, all variants can handle this */
1428		break;
1429	case SSP_TX_16_OR_MORE_EMPTY_LOC:
1430		if (pl022->vendor->fifodepth < 16) {
1431			dev_err(&pl022->adev->dev,
1432			"TX FIFO Trigger Level is configured incorrectly\n");
1433			return -EINVAL;
1434		}
1435		break;
1436	case SSP_TX_32_OR_MORE_EMPTY_LOC:
1437		if (pl022->vendor->fifodepth < 32) {
1438			dev_err(&pl022->adev->dev,
1439			"TX FIFO Trigger Level is configured incorrectly\n");
1440			return -EINVAL;
1441		}
1442		break;
1443	default:
1444		dev_err(&pl022->adev->dev,
1445			"TX FIFO Trigger Level is configured incorrectly\n");
1446		return -EINVAL;
1447	}
1448	if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1449		if ((chip_info->ctrl_len < SSP_BITS_4)
1450		    || (chip_info->ctrl_len > SSP_BITS_32)) {
1451			dev_err(&pl022->adev->dev,
1452				"CTRL LEN is configured incorrectly\n");
1453			return -EINVAL;
1454		}
1455		if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1456		    && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1457			dev_err(&pl022->adev->dev,
1458				"Wait State is configured incorrectly\n");
1459			return -EINVAL;
1460		}
1461		/* Half duplex is only available in the ST Micro version */
1462		if (pl022->vendor->extended_cr) {
1463			if ((chip_info->duplex !=
1464			     SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1465			    && (chip_info->duplex !=
1466				SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1467				dev_err(&pl022->adev->dev,
1468					"Microwire duplex mode is configured incorrectly\n");
1469				return -EINVAL;
1470			}
1471		} else {
1472			if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) {
1473				dev_err(&pl022->adev->dev,
1474					"Microwire half duplex mode requested,"
1475					" but this is only available in the"
1476					" ST version of PL022\n");
1477				return -EINVAL;
1478			}
1479		}
1480	}
1481	return 0;
1482}
1483
1484static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1485{
1486	return rate / (cpsdvsr * (1 + scr));
1487}
1488
1489static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1490				    ssp_clock_params * clk_freq)
1491{
1492	/* Lets calculate the frequency parameters */
1493	u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1494	u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1495		best_scr = 0, tmp, found = 0;
1496
1497	rate = clk_get_rate(pl022->clk);
1498	/* cpsdvscr = 2 & scr 0 */
1499	max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1500	/* cpsdvsr = 254 & scr = 255 */
1501	min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1502
1503	if (freq > max_tclk)
1504		dev_warn(&pl022->adev->dev,
1505			"Max speed that can be programmed is %d Hz, you requested %d\n",
1506			max_tclk, freq);
1507
1508	if (freq < min_tclk) {
1509		dev_err(&pl022->adev->dev,
1510			"Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1511			freq, min_tclk);
1512		return -EINVAL;
1513	}
1514
1515	/*
1516	 * best_freq will give closest possible available rate (<= requested
1517	 * freq) for all values of scr & cpsdvsr.
1518	 */
1519	while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1520		while (scr <= SCR_MAX) {
1521			tmp = spi_rate(rate, cpsdvsr, scr);
1522
1523			if (tmp > freq) {
1524				/* we need lower freq */
1525				scr++;
1526				continue;
1527			}
1528
1529			/*
1530			 * If found exact value, mark found and break.
1531			 * If found more closer value, update and break.
1532			 */
1533			if (tmp > best_freq) {
1534				best_freq = tmp;
1535				best_cpsdvsr = cpsdvsr;
1536				best_scr = scr;
1537
1538				if (tmp == freq)
1539					found = 1;
1540			}
1541			/*
1542			 * increased scr will give lower rates, which are not
1543			 * required
1544			 */
1545			break;
1546		}
1547		cpsdvsr += 2;
1548		scr = SCR_MIN;
1549	}
1550
1551	WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1552			freq);
1553
1554	clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1555	clk_freq->scr = (u8) (best_scr & 0xFF);
1556	dev_dbg(&pl022->adev->dev,
1557		"SSP Target Frequency is: %u, Effective Frequency is %u\n",
1558		freq, best_freq);
1559	dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1560		clk_freq->cpsdvsr, clk_freq->scr);
1561
1562	return 0;
1563}
1564
1565/*
1566 * A piece of default chip info unless the platform
1567 * supplies it.
1568 */
1569static const struct pl022_config_chip pl022_default_chip_info = {
1570	.com_mode = INTERRUPT_TRANSFER,
1571	.iface = SSP_INTERFACE_MOTOROLA_SPI,
1572	.hierarchy = SSP_MASTER,
1573	.slave_tx_disable = DO_NOT_DRIVE_TX,
1574	.rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1575	.tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1576	.ctrl_len = SSP_BITS_8,
1577	.wait_state = SSP_MWIRE_WAIT_ZERO,
1578	.duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
 
1579};
1580
1581/**
1582 * pl022_setup - setup function registered to SPI host framework
1583 * @spi: spi device which is requesting setup
1584 *
1585 * This function is registered to the SPI framework for this SPI host
1586 * controller. If it is the first time when setup is called by this device,
1587 * this function will initialize the runtime state for this chip and save
1588 * the same in the device structure. Else it will update the runtime info
1589 * with the updated chip info. Nothing is really being written to the
1590 * controller hardware here, that is not done until the actual transfer
1591 * commence.
1592 */
1593static int pl022_setup(struct spi_device *spi)
1594{
1595	struct pl022_config_chip const *chip_info;
1596	struct pl022_config_chip chip_info_dt;
1597	struct chip_data *chip;
1598	struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1599	int status = 0;
1600	struct pl022 *pl022 = spi_controller_get_devdata(spi->controller);
1601	unsigned int bits = spi->bits_per_word;
1602	u32 tmp;
1603	struct device_node *np = spi->dev.of_node;
1604
1605	if (!spi->max_speed_hz)
1606		return -EINVAL;
1607
1608	/* Get controller_state if one is supplied */
1609	chip = spi_get_ctldata(spi);
1610
1611	if (chip == NULL) {
1612		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1613		if (!chip)
 
 
1614			return -ENOMEM;
 
1615		dev_dbg(&spi->dev,
1616			"allocated memory for controller's runtime state\n");
1617	}
1618
1619	/* Get controller data if one is supplied */
1620	chip_info = spi->controller_data;
1621
1622	if (chip_info == NULL) {
1623		if (np) {
1624			chip_info_dt = pl022_default_chip_info;
1625
1626			chip_info_dt.hierarchy = SSP_MASTER;
1627			of_property_read_u32(np, "pl022,interface",
1628				&chip_info_dt.iface);
1629			of_property_read_u32(np, "pl022,com-mode",
1630				&chip_info_dt.com_mode);
1631			of_property_read_u32(np, "pl022,rx-level-trig",
1632				&chip_info_dt.rx_lev_trig);
1633			of_property_read_u32(np, "pl022,tx-level-trig",
1634				&chip_info_dt.tx_lev_trig);
1635			of_property_read_u32(np, "pl022,ctrl-len",
1636				&chip_info_dt.ctrl_len);
1637			of_property_read_u32(np, "pl022,wait-state",
1638				&chip_info_dt.wait_state);
1639			of_property_read_u32(np, "pl022,duplex",
1640				&chip_info_dt.duplex);
1641
1642			chip_info = &chip_info_dt;
1643		} else {
1644			chip_info = &pl022_default_chip_info;
1645			/* spi_board_info.controller_data not is supplied */
1646			dev_dbg(&spi->dev,
1647				"using default controller_data settings\n");
1648		}
1649	} else
1650		dev_dbg(&spi->dev,
1651			"using user supplied controller_data settings\n");
1652
1653	/*
1654	 * We can override with custom divisors, else we use the board
1655	 * frequency setting
1656	 */
1657	if ((0 == chip_info->clk_freq.cpsdvsr)
1658	    && (0 == chip_info->clk_freq.scr)) {
1659		status = calculate_effective_freq(pl022,
1660						  spi->max_speed_hz,
1661						  &clk_freq);
1662		if (status < 0)
1663			goto err_config_params;
1664	} else {
1665		memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1666		if ((clk_freq.cpsdvsr % 2) != 0)
1667			clk_freq.cpsdvsr =
1668				clk_freq.cpsdvsr - 1;
1669	}
1670	if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1671	    || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1672		status = -EINVAL;
1673		dev_err(&spi->dev,
1674			"cpsdvsr is configured incorrectly\n");
1675		goto err_config_params;
1676	}
1677
1678	status = verify_controller_parameters(pl022, chip_info);
1679	if (status) {
1680		dev_err(&spi->dev, "controller data is incorrect");
1681		goto err_config_params;
1682	}
1683
1684	pl022->rx_lev_trig = chip_info->rx_lev_trig;
1685	pl022->tx_lev_trig = chip_info->tx_lev_trig;
1686
1687	/* Now set controller state based on controller data */
1688	chip->xfer_type = chip_info->com_mode;
 
 
 
 
 
 
 
1689
1690	/* Check bits per word with vendor specific range */
1691	if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1692		status = -ENOTSUPP;
1693		dev_err(&spi->dev, "illegal data size for this controller!\n");
1694		dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1695				pl022->vendor->max_bpw);
1696		goto err_config_params;
1697	} else if (bits <= 8) {
1698		dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1699		chip->n_bytes = 1;
1700		chip->read = READING_U8;
1701		chip->write = WRITING_U8;
1702	} else if (bits <= 16) {
1703		dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1704		chip->n_bytes = 2;
1705		chip->read = READING_U16;
1706		chip->write = WRITING_U16;
1707	} else {
1708		dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1709		chip->n_bytes = 4;
1710		chip->read = READING_U32;
1711		chip->write = WRITING_U32;
1712	}
1713
1714	/* Now Initialize all register settings required for this chip */
1715	chip->cr0 = 0;
1716	chip->cr1 = 0;
1717	chip->dmacr = 0;
1718	chip->cpsr = 0;
1719	if ((chip_info->com_mode == DMA_TRANSFER)
1720	    && ((pl022->host_info)->enable_dma)) {
1721		chip->enable_dma = true;
1722		dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1723		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1724			       SSP_DMACR_MASK_RXDMAE, 0);
1725		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1726			       SSP_DMACR_MASK_TXDMAE, 1);
1727	} else {
1728		chip->enable_dma = false;
1729		dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1730		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1731			       SSP_DMACR_MASK_RXDMAE, 0);
1732		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1733			       SSP_DMACR_MASK_TXDMAE, 1);
1734	}
1735
1736	chip->cpsr = clk_freq.cpsdvsr;
1737
1738	/* Special setup for the ST micro extended control registers */
1739	if (pl022->vendor->extended_cr) {
1740		u32 etx;
1741
1742		if (pl022->vendor->pl023) {
1743			/* These bits are only in the PL023 */
1744			SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
1745				       SSP_CR1_MASK_FBCLKDEL_ST, 13);
1746		} else {
1747			/* These bits are in the PL022 but not PL023 */
1748			SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
1749				       SSP_CR0_MASK_HALFDUP_ST, 5);
1750			SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
1751				       SSP_CR0_MASK_CSS_ST, 16);
1752			SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1753				       SSP_CR0_MASK_FRF_ST, 21);
1754			SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
1755				       SSP_CR1_MASK_MWAIT_ST, 6);
1756		}
1757		SSP_WRITE_BITS(chip->cr0, bits - 1,
1758			       SSP_CR0_MASK_DSS_ST, 0);
1759
1760		if (spi->mode & SPI_LSB_FIRST) {
1761			tmp = SSP_RX_LSB;
1762			etx = SSP_TX_LSB;
1763		} else {
1764			tmp = SSP_RX_MSB;
1765			etx = SSP_TX_MSB;
1766		}
1767		SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
1768		SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
1769		SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
1770			       SSP_CR1_MASK_RXIFLSEL_ST, 7);
1771		SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
1772			       SSP_CR1_MASK_TXIFLSEL_ST, 10);
1773	} else {
1774		SSP_WRITE_BITS(chip->cr0, bits - 1,
1775			       SSP_CR0_MASK_DSS, 0);
1776		SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1777			       SSP_CR0_MASK_FRF, 4);
1778	}
1779
1780	/* Stuff that is common for all versions */
1781	if (spi->mode & SPI_CPOL)
1782		tmp = SSP_CLK_POL_IDLE_HIGH;
1783	else
1784		tmp = SSP_CLK_POL_IDLE_LOW;
1785	SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
1786
1787	if (spi->mode & SPI_CPHA)
1788		tmp = SSP_CLK_SECOND_EDGE;
1789	else
1790		tmp = SSP_CLK_FIRST_EDGE;
1791	SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
1792
1793	SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
1794	/* Loopback is available on all versions except PL023 */
1795	if (pl022->vendor->loopback) {
1796		if (spi->mode & SPI_LOOP)
1797			tmp = LOOPBACK_ENABLED;
1798		else
1799			tmp = LOOPBACK_DISABLED;
1800		SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
1801	}
1802	SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
1803	SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
1804	SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
1805		3);
1806
1807	/* Save controller_state */
1808	spi_set_ctldata(spi, chip);
1809	return status;
1810 err_config_params:
1811	spi_set_ctldata(spi, NULL);
1812	kfree(chip);
1813	return status;
1814}
1815
1816/**
1817 * pl022_cleanup - cleanup function registered to SPI host framework
1818 * @spi: spi device which is requesting cleanup
1819 *
1820 * This function is registered to the SPI framework for this SPI host
1821 * controller. It will free the runtime state of chip.
1822 */
1823static void pl022_cleanup(struct spi_device *spi)
1824{
1825	struct chip_data *chip = spi_get_ctldata(spi);
1826
1827	spi_set_ctldata(spi, NULL);
1828	kfree(chip);
1829}
1830
1831static struct pl022_ssp_controller *
1832pl022_platform_data_dt_get(struct device *dev)
1833{
1834	struct device_node *np = dev->of_node;
1835	struct pl022_ssp_controller *pd;
 
1836
1837	if (!np) {
1838		dev_err(dev, "no dt node defined\n");
1839		return NULL;
1840	}
1841
1842	pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
1843	if (!pd)
 
1844		return NULL;
 
1845
1846	pd->bus_id = -1;
 
 
 
1847	of_property_read_u32(np, "pl022,autosuspend-delay",
1848			     &pd->autosuspend_delay);
1849	pd->rt = of_property_read_bool(np, "pl022,rt");
1850
1851	return pd;
1852}
1853
1854static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
1855{
1856	struct device *dev = &adev->dev;
1857	struct pl022_ssp_controller *platform_info =
1858			dev_get_platdata(&adev->dev);
1859	struct spi_controller *host;
1860	struct pl022 *pl022 = NULL;	/*Data for this driver */
1861	int status = 0;
 
1862
1863	dev_info(&adev->dev,
1864		 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
1865	if (!platform_info && IS_ENABLED(CONFIG_OF))
1866		platform_info = pl022_platform_data_dt_get(dev);
1867
1868	if (!platform_info) {
1869		dev_err(dev, "probe: no platform data defined\n");
1870		return -ENODEV;
1871	}
1872
1873	/* Allocate host with space for data */
1874	host = spi_alloc_host(dev, sizeof(struct pl022));
1875	if (host == NULL) {
1876		dev_err(&adev->dev, "probe - cannot alloc SPI host\n");
 
 
 
 
 
 
 
1877		return -ENOMEM;
1878	}
1879
1880	pl022 = spi_controller_get_devdata(host);
1881	pl022->host = host;
1882	pl022->host_info = platform_info;
1883	pl022->adev = adev;
1884	pl022->vendor = id->data;
 
 
1885
1886	/*
1887	 * Bus Number Which has been Assigned to this SSP controller
1888	 * on this board
1889	 */
1890	host->bus_num = platform_info->bus_id;
1891	host->cleanup = pl022_cleanup;
1892	host->setup = pl022_setup;
1893	host->auto_runtime_pm = true;
1894	host->transfer_one = pl022_transfer_one;
1895	host->set_cs = pl022_cs_control;
1896	host->handle_err = pl022_handle_err;
1897	host->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
1898	host->rt = platform_info->rt;
1899	host->dev.of_node = dev->of_node;
1900	host->use_gpio_descriptors = true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1901
1902	/*
1903	 * Supports mode 0-3, loopback, and active low CS. Transfers are
1904	 * always MS bit first on the original pl022.
1905	 */
1906	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1907	if (pl022->vendor->extended_cr)
1908		host->mode_bits |= SPI_LSB_FIRST;
1909
1910	dev_dbg(&adev->dev, "BUSNO: %d\n", host->bus_num);
1911
1912	status = amba_request_regions(adev, NULL);
1913	if (status)
1914		goto err_no_ioregion;
1915
1916	pl022->phybase = adev->res.start;
1917	pl022->virtbase = devm_ioremap(dev, adev->res.start,
1918				       resource_size(&adev->res));
1919	if (pl022->virtbase == NULL) {
1920		status = -ENOMEM;
1921		goto err_no_ioremap;
1922	}
1923	dev_info(&adev->dev, "mapped registers from %pa to %p\n",
1924		&adev->res.start, pl022->virtbase);
1925
1926	pl022->clk = devm_clk_get_enabled(&adev->dev, NULL);
1927	if (IS_ERR(pl022->clk)) {
1928		status = PTR_ERR(pl022->clk);
1929		dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
1930		goto err_no_clk;
1931	}
1932
 
 
 
 
 
 
 
 
 
 
1933	/* Disable SSP */
1934	writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
1935	       SSP_CR1(pl022->virtbase));
1936	load_ssp_default_config(pl022);
1937
1938	status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
1939				  0, "pl022", pl022);
1940	if (status < 0) {
1941		dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
1942		goto err_no_irq;
1943	}
1944
1945	/* Get DMA channels, try autoconfiguration first */
1946	status = pl022_dma_autoprobe(pl022);
1947	if (status == -EPROBE_DEFER) {
1948		dev_dbg(dev, "deferring probe to get DMA channel\n");
1949		goto err_no_irq;
1950	}
1951
1952	/* If that failed, use channels from platform_info */
1953	if (status == 0)
1954		platform_info->enable_dma = 1;
1955	else if (platform_info->enable_dma) {
1956		status = pl022_dma_probe(pl022);
1957		if (status != 0)
1958			platform_info->enable_dma = 0;
1959	}
1960
1961	/* Register with the SPI framework */
1962	amba_set_drvdata(adev, pl022);
1963	status = devm_spi_register_controller(&adev->dev, host);
1964	if (status != 0) {
1965		dev_err_probe(&adev->dev, status,
1966			      "problem registering spi host\n");
1967		goto err_spi_register;
1968	}
1969	dev_dbg(dev, "probe succeeded\n");
1970
1971	/* let runtime pm put suspend */
1972	if (platform_info->autosuspend_delay > 0) {
1973		dev_info(&adev->dev,
1974			"will use autosuspend for runtime pm, delay %dms\n",
1975			platform_info->autosuspend_delay);
1976		pm_runtime_set_autosuspend_delay(dev,
1977			platform_info->autosuspend_delay);
1978		pm_runtime_use_autosuspend(dev);
1979	}
1980	pm_runtime_put(dev);
1981
1982	return 0;
1983
1984 err_spi_register:
1985	if (platform_info->enable_dma)
1986		pl022_dma_remove(pl022);
1987 err_no_irq:
 
 
1988 err_no_clk:
1989 err_no_ioremap:
1990	amba_release_regions(adev);
1991 err_no_ioregion:
1992	spi_controller_put(host);
 
1993	return status;
1994}
1995
1996static void
1997pl022_remove(struct amba_device *adev)
1998{
1999	struct pl022 *pl022 = amba_get_drvdata(adev);
2000
2001	if (!pl022)
2002		return;
2003
2004	/*
2005	 * undo pm_runtime_put() in probe.  I assume that we're not
2006	 * accessing the primecell here.
2007	 */
2008	pm_runtime_get_noresume(&adev->dev);
2009
2010	load_ssp_default_config(pl022);
2011	if (pl022->host_info->enable_dma)
2012		pl022_dma_remove(pl022);
2013
 
2014	amba_release_regions(adev);
 
 
2015}
2016
2017#ifdef CONFIG_PM_SLEEP
2018static int pl022_suspend(struct device *dev)
2019{
2020	struct pl022 *pl022 = dev_get_drvdata(dev);
2021	int ret;
2022
2023	ret = spi_controller_suspend(pl022->host);
2024	if (ret)
 
2025		return ret;
 
2026
2027	ret = pm_runtime_force_suspend(dev);
2028	if (ret) {
2029		spi_controller_resume(pl022->host);
2030		return ret;
2031	}
2032
2033	pinctrl_pm_select_sleep_state(dev);
2034
2035	dev_dbg(dev, "suspended\n");
2036	return 0;
2037}
2038
2039static int pl022_resume(struct device *dev)
2040{
2041	struct pl022 *pl022 = dev_get_drvdata(dev);
2042	int ret;
2043
2044	ret = pm_runtime_force_resume(dev);
2045	if (ret)
2046		dev_err(dev, "problem resuming\n");
2047
2048	/* Start the queue running */
2049	ret = spi_controller_resume(pl022->host);
2050	if (!ret)
 
 
2051		dev_dbg(dev, "resumed\n");
2052
2053	return ret;
2054}
2055#endif
2056
2057#ifdef CONFIG_PM
2058static int pl022_runtime_suspend(struct device *dev)
2059{
2060	struct pl022 *pl022 = dev_get_drvdata(dev);
2061
2062	clk_disable_unprepare(pl022->clk);
2063	pinctrl_pm_select_idle_state(dev);
2064
2065	return 0;
2066}
2067
2068static int pl022_runtime_resume(struct device *dev)
2069{
2070	struct pl022 *pl022 = dev_get_drvdata(dev);
2071
2072	pinctrl_pm_select_default_state(dev);
2073	clk_prepare_enable(pl022->clk);
2074
2075	return 0;
2076}
2077#endif
2078
2079static const struct dev_pm_ops pl022_dev_pm_ops = {
2080	SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2081	SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2082};
2083
2084static struct vendor_data vendor_arm = {
2085	.fifodepth = 8,
2086	.max_bpw = 16,
2087	.unidir = false,
2088	.extended_cr = false,
2089	.pl023 = false,
2090	.loopback = true,
2091	.internal_cs_ctrl = false,
2092};
2093
2094static struct vendor_data vendor_st = {
2095	.fifodepth = 32,
2096	.max_bpw = 32,
2097	.unidir = false,
2098	.extended_cr = true,
2099	.pl023 = false,
2100	.loopback = true,
2101	.internal_cs_ctrl = false,
2102};
2103
2104static struct vendor_data vendor_st_pl023 = {
2105	.fifodepth = 32,
2106	.max_bpw = 32,
2107	.unidir = false,
2108	.extended_cr = true,
2109	.pl023 = true,
2110	.loopback = false,
2111	.internal_cs_ctrl = false,
2112};
2113
2114static struct vendor_data vendor_lsi = {
2115	.fifodepth = 8,
2116	.max_bpw = 16,
2117	.unidir = false,
2118	.extended_cr = false,
2119	.pl023 = false,
2120	.loopback = true,
2121	.internal_cs_ctrl = true,
2122};
2123
2124static const struct amba_id pl022_ids[] = {
2125	{
2126		/*
2127		 * ARM PL022 variant, this has a 16bit wide
2128		 * and 8 locations deep TX/RX FIFO
2129		 */
2130		.id	= 0x00041022,
2131		.mask	= 0x000fffff,
2132		.data	= &vendor_arm,
2133	},
2134	{
2135		/*
2136		 * ST Micro derivative, this has 32bit wide
2137		 * and 32 locations deep TX/RX FIFO
2138		 */
2139		.id	= 0x01080022,
2140		.mask	= 0xffffffff,
2141		.data	= &vendor_st,
2142	},
2143	{
2144		/*
2145		 * ST-Ericsson derivative "PL023" (this is not
2146		 * an official ARM number), this is a PL022 SSP block
2147		 * stripped to SPI mode only, it has 32bit wide
2148		 * and 32 locations deep TX/RX FIFO but no extended
2149		 * CR0/CR1 register
2150		 */
2151		.id	= 0x00080023,
2152		.mask	= 0xffffffff,
2153		.data	= &vendor_st_pl023,
2154	},
2155	{
2156		/*
2157		 * PL022 variant that has a chip select control register whih
2158		 * allows control of 5 output signals nCS[0:4].
2159		 */
2160		.id	= 0x000b6022,
2161		.mask	= 0x000fffff,
2162		.data	= &vendor_lsi,
2163	},
2164	{ 0, 0 },
2165};
2166
2167MODULE_DEVICE_TABLE(amba, pl022_ids);
2168
2169static struct amba_driver pl022_driver = {
2170	.drv = {
2171		.name	= "ssp-pl022",
2172		.pm	= &pl022_dev_pm_ops,
2173	},
2174	.id_table	= pl022_ids,
2175	.probe		= pl022_probe,
2176	.remove		= pl022_remove,
2177};
2178
2179static int __init pl022_init(void)
2180{
2181	return amba_driver_register(&pl022_driver);
2182}
2183subsys_initcall(pl022_init);
2184
2185static void __exit pl022_exit(void)
2186{
2187	amba_driver_unregister(&pl022_driver);
2188}
2189module_exit(pl022_exit);
2190
2191MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2192MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2193MODULE_LICENSE("GPL");