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v5.4
   1// SPDX-License-Identifier: GPL-2.0+
   2// Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3// Copyright (C) 2008 Juergen Beisert
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   4
   5#include <linux/clk.h>
   6#include <linux/completion.h>
   7#include <linux/delay.h>
   8#include <linux/dmaengine.h>
   9#include <linux/dma-mapping.h>
  10#include <linux/err.h>
  11#include <linux/gpio.h>
  12#include <linux/interrupt.h>
  13#include <linux/io.h>
  14#include <linux/irq.h>
  15#include <linux/kernel.h>
  16#include <linux/module.h>
  17#include <linux/platform_device.h>
  18#include <linux/slab.h>
  19#include <linux/spi/spi.h>
  20#include <linux/spi/spi_bitbang.h>
  21#include <linux/types.h>
  22#include <linux/of.h>
  23#include <linux/of_device.h>
  24#include <linux/of_gpio.h>
  25
  26#include <linux/platform_data/dma-imx.h>
  27#include <linux/platform_data/spi-imx.h>
  28
  29#define DRIVER_NAME "spi_imx"
  30
  31static bool use_dma = true;
  32module_param(use_dma, bool, 0644);
  33MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
  34
  35#define MXC_CSPIRXDATA		0x00
  36#define MXC_CSPITXDATA		0x04
  37#define MXC_CSPICTRL		0x08
  38#define MXC_CSPIINT		0x0c
  39#define MXC_RESET		0x1c
  40
  41/* generic defines to abstract from the different register layouts */
  42#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
  43#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
  44#define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
  45
  46/* The maximum bytes that a sdma BD can transfer. */
  47#define MAX_SDMA_BD_BYTES (1 << 15)
  48#define MX51_ECSPI_CTRL_MAX_BURST	512
  49/* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
  50#define MX53_MAX_TRANSFER_BYTES		512
 
 
 
  51
  52enum spi_imx_devtype {
  53	IMX1_CSPI,
  54	IMX21_CSPI,
  55	IMX27_CSPI,
  56	IMX31_CSPI,
  57	IMX35_CSPI,	/* CSPI on all i.mx except above */
  58	IMX51_ECSPI,	/* ECSPI on i.mx51 */
  59	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
  60};
  61
  62struct spi_imx_data;
  63
  64struct spi_imx_devtype_data {
  65	void (*intctrl)(struct spi_imx_data *, int);
  66	int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
  67	int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *,
  68				struct spi_transfer *);
  69	void (*trigger)(struct spi_imx_data *);
  70	int (*rx_available)(struct spi_imx_data *);
  71	void (*reset)(struct spi_imx_data *);
  72	void (*setup_wml)(struct spi_imx_data *);
  73	void (*disable)(struct spi_imx_data *);
  74	bool has_dmamode;
  75	bool has_slavemode;
  76	unsigned int fifo_size;
  77	bool dynamic_burst;
  78	enum spi_imx_devtype devtype;
  79};
  80
  81struct spi_imx_data {
  82	struct spi_bitbang bitbang;
  83	struct device *dev;
  84
  85	struct completion xfer_done;
  86	void __iomem *base;
  87	unsigned long base_phys;
  88
  89	struct clk *clk_per;
  90	struct clk *clk_ipg;
  91	unsigned long spi_clk;
  92	unsigned int spi_bus_clk;
  93
  94	unsigned int bits_per_word;
  95	unsigned int spi_drctl;
  96
  97	unsigned int count, remainder;
  98	void (*tx)(struct spi_imx_data *);
  99	void (*rx)(struct spi_imx_data *);
 100	void *rx_buf;
 101	const void *tx_buf;
 102	unsigned int txfifo; /* number of words pushed in tx FIFO */
 103	unsigned int dynamic_burst;
 104
 105	/* Slave mode */
 106	bool slave_mode;
 107	bool slave_aborted;
 108	unsigned int slave_burst;
 109
 110	/* DMA */
 111	bool usedma;
 112	u32 wml;
 113	struct completion dma_rx_completion;
 114	struct completion dma_tx_completion;
 115
 116	const struct spi_imx_devtype_data *devtype_data;
 
 117};
 118
 119static inline int is_imx27_cspi(struct spi_imx_data *d)
 120{
 121	return d->devtype_data->devtype == IMX27_CSPI;
 122}
 123
 124static inline int is_imx35_cspi(struct spi_imx_data *d)
 125{
 126	return d->devtype_data->devtype == IMX35_CSPI;
 127}
 128
 129static inline int is_imx51_ecspi(struct spi_imx_data *d)
 130{
 131	return d->devtype_data->devtype == IMX51_ECSPI;
 132}
 133
 134static inline int is_imx53_ecspi(struct spi_imx_data *d)
 135{
 136	return d->devtype_data->devtype == IMX53_ECSPI;
 137}
 138
 139#define MXC_SPI_BUF_RX(type)						\
 140static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 141{									\
 142	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 143									\
 144	if (spi_imx->rx_buf) {						\
 145		*(type *)spi_imx->rx_buf = val;				\
 146		spi_imx->rx_buf += sizeof(type);			\
 147	}								\
 148									\
 149	spi_imx->remainder -= sizeof(type);				\
 150}
 151
 152#define MXC_SPI_BUF_TX(type)						\
 153static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 154{									\
 155	type val = 0;							\
 156									\
 157	if (spi_imx->tx_buf) {						\
 158		val = *(type *)spi_imx->tx_buf;				\
 159		spi_imx->tx_buf += sizeof(type);			\
 160	}								\
 161									\
 162	spi_imx->count -= sizeof(type);					\
 163									\
 164	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 165}
 166
 167MXC_SPI_BUF_RX(u8)
 168MXC_SPI_BUF_TX(u8)
 169MXC_SPI_BUF_RX(u16)
 170MXC_SPI_BUF_TX(u16)
 171MXC_SPI_BUF_RX(u32)
 172MXC_SPI_BUF_TX(u32)
 173
 174/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 175 * (which is currently not the case in this driver)
 176 */
 177static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 178	256, 384, 512, 768, 1024};
 179
 180/* MX21, MX27 */
 181static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 182		unsigned int fspi, unsigned int max, unsigned int *fres)
 183{
 184	int i;
 185
 186	for (i = 2; i < max; i++)
 187		if (fspi * mxc_clkdivs[i] >= fin)
 188			break;
 189
 190	*fres = fin / mxc_clkdivs[i];
 191	return i;
 192}
 193
 194/* MX1, MX31, MX35, MX51 CSPI */
 195static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 196		unsigned int fspi, unsigned int *fres)
 197{
 198	int i, div = 4;
 199
 200	for (i = 0; i < 7; i++) {
 201		if (fspi * div >= fin)
 202			goto out;
 203		div <<= 1;
 204	}
 205
 206out:
 207	*fres = fin / div;
 208	return i;
 209}
 210
 211static int spi_imx_bytes_per_word(const int bits_per_word)
 212{
 213	if (bits_per_word <= 8)
 214		return 1;
 215	else if (bits_per_word <= 16)
 216		return 2;
 217	else
 218		return 4;
 219}
 220
 221static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 222			 struct spi_transfer *transfer)
 223{
 224	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 
 225
 226	if (!use_dma)
 227		return false;
 228
 229	if (!master->dma_rx)
 230		return false;
 231
 232	if (spi_imx->slave_mode)
 
 
 
 
 
 
 233		return false;
 234
 235	if (transfer->len < spi_imx->devtype_data->fifo_size)
 236		return false;
 237
 238	spi_imx->dynamic_burst = 0;
 
 239
 240	return true;
 241}
 242
 243#define MX51_ECSPI_CTRL		0x08
 244#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
 245#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 246#define MX51_ECSPI_CTRL_SMC		(1 << 3)
 247#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 248#define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
 249#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
 250#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 251#define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
 252#define MX51_ECSPI_CTRL_BL_OFFSET	20
 253#define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
 254
 255#define MX51_ECSPI_CONFIG	0x0c
 256#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
 257#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
 258#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
 259#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
 260#define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
 261
 262#define MX51_ECSPI_INT		0x10
 263#define MX51_ECSPI_INT_TEEN		(1 <<  0)
 264#define MX51_ECSPI_INT_RREN		(1 <<  3)
 265#define MX51_ECSPI_INT_RDREN		(1 <<  4)
 266
 267#define MX51_ECSPI_DMA		0x14
 268#define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
 269#define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
 270#define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
 271
 272#define MX51_ECSPI_DMA_TEDEN		(1 << 7)
 273#define MX51_ECSPI_DMA_RXDEN		(1 << 23)
 274#define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
 275
 276#define MX51_ECSPI_STAT		0x18
 277#define MX51_ECSPI_STAT_RR		(1 <<  3)
 278
 279#define MX51_ECSPI_TESTREG	0x20
 280#define MX51_ECSPI_TESTREG_LBC	BIT(31)
 281
 282static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
 283{
 284	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
 285#ifdef __LITTLE_ENDIAN
 286	unsigned int bytes_per_word;
 287#endif
 288
 289	if (spi_imx->rx_buf) {
 290#ifdef __LITTLE_ENDIAN
 291		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 292		if (bytes_per_word == 1)
 293			val = cpu_to_be32(val);
 294		else if (bytes_per_word == 2)
 295			val = (val << 16) | (val >> 16);
 296#endif
 297		*(u32 *)spi_imx->rx_buf = val;
 298		spi_imx->rx_buf += sizeof(u32);
 299	}
 300
 301	spi_imx->remainder -= sizeof(u32);
 302}
 303
 304static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
 305{
 306	int unaligned;
 307	u32 val;
 308
 309	unaligned = spi_imx->remainder % 4;
 310
 311	if (!unaligned) {
 312		spi_imx_buf_rx_swap_u32(spi_imx);
 313		return;
 314	}
 315
 316	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 317		spi_imx_buf_rx_u16(spi_imx);
 318		return;
 319	}
 320
 321	val = readl(spi_imx->base + MXC_CSPIRXDATA);
 322
 323	while (unaligned--) {
 324		if (spi_imx->rx_buf) {
 325			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
 326			spi_imx->rx_buf++;
 327		}
 328		spi_imx->remainder--;
 329	}
 330}
 331
 332static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
 333{
 334	u32 val = 0;
 335#ifdef __LITTLE_ENDIAN
 336	unsigned int bytes_per_word;
 337#endif
 338
 339	if (spi_imx->tx_buf) {
 340		val = *(u32 *)spi_imx->tx_buf;
 341		spi_imx->tx_buf += sizeof(u32);
 342	}
 343
 344	spi_imx->count -= sizeof(u32);
 345#ifdef __LITTLE_ENDIAN
 346	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 347
 348	if (bytes_per_word == 1)
 349		val = cpu_to_be32(val);
 350	else if (bytes_per_word == 2)
 351		val = (val << 16) | (val >> 16);
 352#endif
 353	writel(val, spi_imx->base + MXC_CSPITXDATA);
 354}
 355
 356static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
 357{
 358	int unaligned;
 359	u32 val = 0;
 360
 361	unaligned = spi_imx->count % 4;
 362
 363	if (!unaligned) {
 364		spi_imx_buf_tx_swap_u32(spi_imx);
 365		return;
 366	}
 367
 368	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 369		spi_imx_buf_tx_u16(spi_imx);
 370		return;
 371	}
 372
 373	while (unaligned--) {
 374		if (spi_imx->tx_buf) {
 375			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
 376			spi_imx->tx_buf++;
 377		}
 378		spi_imx->count--;
 379	}
 380
 381	writel(val, spi_imx->base + MXC_CSPITXDATA);
 382}
 383
 384static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
 385{
 386	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
 387
 388	if (spi_imx->rx_buf) {
 389		int n_bytes = spi_imx->slave_burst % sizeof(val);
 390
 391		if (!n_bytes)
 392			n_bytes = sizeof(val);
 393
 394		memcpy(spi_imx->rx_buf,
 395		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
 396
 397		spi_imx->rx_buf += n_bytes;
 398		spi_imx->slave_burst -= n_bytes;
 399	}
 400
 401	spi_imx->remainder -= sizeof(u32);
 402}
 403
 404static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
 405{
 406	u32 val = 0;
 407	int n_bytes = spi_imx->count % sizeof(val);
 408
 409	if (!n_bytes)
 410		n_bytes = sizeof(val);
 411
 412	if (spi_imx->tx_buf) {
 413		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
 414		       spi_imx->tx_buf, n_bytes);
 415		val = cpu_to_be32(val);
 416		spi_imx->tx_buf += n_bytes;
 417	}
 418
 419	spi_imx->count -= n_bytes;
 420
 421	writel(val, spi_imx->base + MXC_CSPITXDATA);
 422}
 423
 424/* MX51 eCSPI */
 425static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 426				      unsigned int fspi, unsigned int *fres)
 427{
 428	/*
 429	 * there are two 4-bit dividers, the pre-divider divides by
 430	 * $pre, the post-divider by 2^$post
 431	 */
 432	unsigned int pre, post;
 433	unsigned int fin = spi_imx->spi_clk;
 434
 435	if (unlikely(fspi > fin))
 436		return 0;
 437
 438	post = fls(fin) - fls(fspi);
 439	if (fin > fspi << post)
 440		post++;
 441
 442	/* now we have: (fin <= fspi << post) with post being minimal */
 443
 444	post = max(4U, post) - 4;
 445	if (unlikely(post > 0xf)) {
 446		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 447				fspi, fin);
 448		return 0xff;
 449	}
 450
 451	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 452
 453	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 454			__func__, fin, fspi, post, pre);
 455
 456	/* Resulting frequency for the SCLK line. */
 457	*fres = (fin / (pre + 1)) >> post;
 458
 459	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 460		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 461}
 462
 463static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 464{
 465	unsigned val = 0;
 466
 467	if (enable & MXC_INT_TE)
 468		val |= MX51_ECSPI_INT_TEEN;
 469
 470	if (enable & MXC_INT_RR)
 471		val |= MX51_ECSPI_INT_RREN;
 472
 473	if (enable & MXC_INT_RDR)
 474		val |= MX51_ECSPI_INT_RDREN;
 475
 476	writel(val, spi_imx->base + MX51_ECSPI_INT);
 477}
 478
 479static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 480{
 481	u32 reg;
 482
 483	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 484	reg |= MX51_ECSPI_CTRL_XCH;
 485	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 486}
 487
 488static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
 
 489{
 490	u32 ctrl;
 491
 492	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 493	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
 494	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 495}
 496
 497static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
 498				      struct spi_message *msg)
 499{
 500	struct spi_device *spi = msg->spi;
 501	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 502	u32 testreg;
 503	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 504
 505	/* set Master or Slave mode */
 506	if (spi_imx->slave_mode)
 507		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
 508	else
 509		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 510
 511	/*
 512	 * Enable SPI_RDY handling (falling edge/level triggered).
 
 
 
 
 513	 */
 514	if (spi->mode & SPI_READY)
 515		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
 516
 517	/* set chip select to use */
 518	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
 
 519
 520	/*
 521	 * The ctrl register must be written first, with the EN bit set other
 522	 * registers must not be written to.
 523	 */
 524	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 525
 526	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 527	if (spi->mode & SPI_LOOP)
 528		testreg |= MX51_ECSPI_TESTREG_LBC;
 529	else
 530		testreg &= ~MX51_ECSPI_TESTREG_LBC;
 531	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
 532
 533	/*
 534	 * eCSPI burst completion by Chip Select signal in Slave mode
 535	 * is not functional for imx53 Soc, config SPI burst completed when
 536	 * BURST_LENGTH + 1 bits are received
 537	 */
 538	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 539		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 540	else
 541		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 542
 543	if (spi->mode & SPI_CPHA)
 544		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 545	else
 546		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 547
 548	if (spi->mode & SPI_CPOL) {
 549		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 550		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 551	} else {
 552		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 553		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 554	}
 555
 556	if (spi->mode & SPI_CS_HIGH)
 557		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 558	else
 559		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 560
 561	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 562
 563	return 0;
 564}
 565
 566static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
 567				       struct spi_device *spi,
 568				       struct spi_transfer *t)
 569{
 570	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 571	u32 clk = t->speed_hz, delay;
 572
 573	/* Clear BL field and set the right value */
 574	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
 575	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 576		ctrl |= (spi_imx->slave_burst * 8 - 1)
 577			<< MX51_ECSPI_CTRL_BL_OFFSET;
 578	else
 579		ctrl |= (spi_imx->bits_per_word - 1)
 580			<< MX51_ECSPI_CTRL_BL_OFFSET;
 581
 582	/* set clock speed */
 583	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
 584		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
 585	ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk);
 586	spi_imx->spi_bus_clk = clk;
 587
 588	if (spi_imx->usedma)
 589		ctrl |= MX51_ECSPI_CTRL_SMC;
 590
 
 591	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 592
 
 
 
 
 
 
 
 
 
 593	/*
 594	 * Wait until the changes in the configuration register CONFIGREG
 595	 * propagate into the hardware. It takes exactly one tick of the
 596	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 597	 * effect of the delay it takes for the hardware to apply changes
 598	 * is noticable if the SCLK clock run very slow. In such a case, if
 599	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 600	 * be asserted before the SCLK polarity changes, which would disrupt
 601	 * the SPI communication as the device on the other end would consider
 602	 * the change of SCLK polarity as a clock tick already.
 603	 */
 604	delay = (2 * 1000000) / clk;
 605	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
 606		udelay(delay);
 607	else			/* SCLK is _very_ slow */
 608		usleep_range(delay, delay + 10);
 609
 610	return 0;
 611}
 612
 613static void mx51_setup_wml(struct spi_imx_data *spi_imx)
 614{
 615	/*
 616	 * Configure the DMA register: setup the watermark
 617	 * and enable DMA request.
 618	 */
 619	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
 
 620		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 621		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 622		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 623		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 
 
 624}
 625
 626static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 627{
 628	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 629}
 630
 631static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 632{
 633	/* drain receive buffer */
 634	while (mx51_ecspi_rx_available(spi_imx))
 635		readl(spi_imx->base + MXC_CSPIRXDATA);
 636}
 637
 638#define MX31_INTREG_TEEN	(1 << 0)
 639#define MX31_INTREG_RREN	(1 << 3)
 640
 641#define MX31_CSPICTRL_ENABLE	(1 << 0)
 642#define MX31_CSPICTRL_MASTER	(1 << 1)
 643#define MX31_CSPICTRL_XCH	(1 << 2)
 644#define MX31_CSPICTRL_SMC	(1 << 3)
 645#define MX31_CSPICTRL_POL	(1 << 4)
 646#define MX31_CSPICTRL_PHA	(1 << 5)
 647#define MX31_CSPICTRL_SSCTL	(1 << 6)
 648#define MX31_CSPICTRL_SSPOL	(1 << 7)
 649#define MX31_CSPICTRL_BC_SHIFT	8
 650#define MX35_CSPICTRL_BL_SHIFT	20
 651#define MX31_CSPICTRL_CS_SHIFT	24
 652#define MX35_CSPICTRL_CS_SHIFT	12
 653#define MX31_CSPICTRL_DR_SHIFT	16
 654
 655#define MX31_CSPI_DMAREG	0x10
 656#define MX31_DMAREG_RH_DEN	(1<<4)
 657#define MX31_DMAREG_TH_DEN	(1<<1)
 658
 659#define MX31_CSPISTATUS		0x14
 660#define MX31_STATUS_RR		(1 << 3)
 661
 662#define MX31_CSPI_TESTREG	0x1C
 663#define MX31_TEST_LBC		(1 << 14)
 664
 665/* These functions also work for the i.MX35, but be aware that
 666 * the i.MX35 has a slightly different register layout for bits
 667 * we do not use here.
 668 */
 669static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 670{
 671	unsigned int val = 0;
 672
 673	if (enable & MXC_INT_TE)
 674		val |= MX31_INTREG_TEEN;
 675	if (enable & MXC_INT_RR)
 676		val |= MX31_INTREG_RREN;
 677
 678	writel(val, spi_imx->base + MXC_CSPIINT);
 679}
 680
 681static void mx31_trigger(struct spi_imx_data *spi_imx)
 682{
 683	unsigned int reg;
 684
 685	reg = readl(spi_imx->base + MXC_CSPICTRL);
 686	reg |= MX31_CSPICTRL_XCH;
 687	writel(reg, spi_imx->base + MXC_CSPICTRL);
 688}
 689
 690static int mx31_prepare_message(struct spi_imx_data *spi_imx,
 691				struct spi_message *msg)
 692{
 693	return 0;
 694}
 695
 696static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
 697				 struct spi_device *spi,
 698				 struct spi_transfer *t)
 699{
 700	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 701	unsigned int clk;
 702
 703	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
 704		MX31_CSPICTRL_DR_SHIFT;
 705	spi_imx->spi_bus_clk = clk;
 706
 707	if (is_imx35_cspi(spi_imx)) {
 708		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
 709		reg |= MX31_CSPICTRL_SSCTL;
 710	} else {
 711		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
 712	}
 713
 714	if (spi->mode & SPI_CPHA)
 715		reg |= MX31_CSPICTRL_PHA;
 716	if (spi->mode & SPI_CPOL)
 717		reg |= MX31_CSPICTRL_POL;
 718	if (spi->mode & SPI_CS_HIGH)
 719		reg |= MX31_CSPICTRL_SSPOL;
 720	if (!gpio_is_valid(spi->cs_gpio))
 721		reg |= (spi->chip_select) <<
 722			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 723						  MX31_CSPICTRL_CS_SHIFT);
 724
 725	if (spi_imx->usedma)
 726		reg |= MX31_CSPICTRL_SMC;
 727
 728	writel(reg, spi_imx->base + MXC_CSPICTRL);
 729
 730	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
 731	if (spi->mode & SPI_LOOP)
 732		reg |= MX31_TEST_LBC;
 733	else
 734		reg &= ~MX31_TEST_LBC;
 735	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 736
 737	if (spi_imx->usedma) {
 738		/*
 739		 * configure DMA requests when RXFIFO is half full and
 740		 * when TXFIFO is half empty
 741		 */
 742		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
 743			spi_imx->base + MX31_CSPI_DMAREG);
 744	}
 745
 746	return 0;
 747}
 748
 749static int mx31_rx_available(struct spi_imx_data *spi_imx)
 750{
 751	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 752}
 753
 754static void mx31_reset(struct spi_imx_data *spi_imx)
 755{
 756	/* drain receive buffer */
 757	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 758		readl(spi_imx->base + MXC_CSPIRXDATA);
 759}
 760
 761#define MX21_INTREG_RR		(1 << 4)
 762#define MX21_INTREG_TEEN	(1 << 9)
 763#define MX21_INTREG_RREN	(1 << 13)
 764
 765#define MX21_CSPICTRL_POL	(1 << 5)
 766#define MX21_CSPICTRL_PHA	(1 << 6)
 767#define MX21_CSPICTRL_SSPOL	(1 << 8)
 768#define MX21_CSPICTRL_XCH	(1 << 9)
 769#define MX21_CSPICTRL_ENABLE	(1 << 10)
 770#define MX21_CSPICTRL_MASTER	(1 << 11)
 771#define MX21_CSPICTRL_DR_SHIFT	14
 772#define MX21_CSPICTRL_CS_SHIFT	19
 773
 774static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 775{
 776	unsigned int val = 0;
 777
 778	if (enable & MXC_INT_TE)
 779		val |= MX21_INTREG_TEEN;
 780	if (enable & MXC_INT_RR)
 781		val |= MX21_INTREG_RREN;
 782
 783	writel(val, spi_imx->base + MXC_CSPIINT);
 784}
 785
 786static void mx21_trigger(struct spi_imx_data *spi_imx)
 787{
 788	unsigned int reg;
 789
 790	reg = readl(spi_imx->base + MXC_CSPICTRL);
 791	reg |= MX21_CSPICTRL_XCH;
 792	writel(reg, spi_imx->base + MXC_CSPICTRL);
 793}
 794
 795static int mx21_prepare_message(struct spi_imx_data *spi_imx,
 796				struct spi_message *msg)
 797{
 798	return 0;
 799}
 800
 801static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
 802				 struct spi_device *spi,
 803				 struct spi_transfer *t)
 804{
 805	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 
 806	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 807	unsigned int clk;
 808
 809	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, t->speed_hz, max, &clk)
 810		<< MX21_CSPICTRL_DR_SHIFT;
 811	spi_imx->spi_bus_clk = clk;
 812
 813	reg |= spi_imx->bits_per_word - 1;
 
 
 814
 815	if (spi->mode & SPI_CPHA)
 816		reg |= MX21_CSPICTRL_PHA;
 817	if (spi->mode & SPI_CPOL)
 818		reg |= MX21_CSPICTRL_POL;
 819	if (spi->mode & SPI_CS_HIGH)
 820		reg |= MX21_CSPICTRL_SSPOL;
 821	if (!gpio_is_valid(spi->cs_gpio))
 822		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
 823
 824	writel(reg, spi_imx->base + MXC_CSPICTRL);
 825
 826	return 0;
 827}
 828
 829static int mx21_rx_available(struct spi_imx_data *spi_imx)
 830{
 831	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 832}
 833
 834static void mx21_reset(struct spi_imx_data *spi_imx)
 835{
 836	writel(1, spi_imx->base + MXC_RESET);
 837}
 838
 839#define MX1_INTREG_RR		(1 << 3)
 840#define MX1_INTREG_TEEN		(1 << 8)
 841#define MX1_INTREG_RREN		(1 << 11)
 842
 843#define MX1_CSPICTRL_POL	(1 << 4)
 844#define MX1_CSPICTRL_PHA	(1 << 5)
 845#define MX1_CSPICTRL_XCH	(1 << 8)
 846#define MX1_CSPICTRL_ENABLE	(1 << 9)
 847#define MX1_CSPICTRL_MASTER	(1 << 10)
 848#define MX1_CSPICTRL_DR_SHIFT	13
 849
 850static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 851{
 852	unsigned int val = 0;
 853
 854	if (enable & MXC_INT_TE)
 855		val |= MX1_INTREG_TEEN;
 856	if (enable & MXC_INT_RR)
 857		val |= MX1_INTREG_RREN;
 858
 859	writel(val, spi_imx->base + MXC_CSPIINT);
 860}
 861
 862static void mx1_trigger(struct spi_imx_data *spi_imx)
 863{
 864	unsigned int reg;
 865
 866	reg = readl(spi_imx->base + MXC_CSPICTRL);
 867	reg |= MX1_CSPICTRL_XCH;
 868	writel(reg, spi_imx->base + MXC_CSPICTRL);
 869}
 870
 871static int mx1_prepare_message(struct spi_imx_data *spi_imx,
 872			       struct spi_message *msg)
 873{
 874	return 0;
 875}
 876
 877static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
 878				struct spi_device *spi,
 879				struct spi_transfer *t)
 880{
 881	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 882	unsigned int clk;
 883
 884	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
 885		MX1_CSPICTRL_DR_SHIFT;
 886	spi_imx->spi_bus_clk = clk;
 887
 888	reg |= spi_imx->bits_per_word - 1;
 889
 890	if (spi->mode & SPI_CPHA)
 891		reg |= MX1_CSPICTRL_PHA;
 892	if (spi->mode & SPI_CPOL)
 893		reg |= MX1_CSPICTRL_POL;
 894
 895	writel(reg, spi_imx->base + MXC_CSPICTRL);
 896
 897	return 0;
 898}
 899
 900static int mx1_rx_available(struct spi_imx_data *spi_imx)
 901{
 902	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 903}
 904
 905static void mx1_reset(struct spi_imx_data *spi_imx)
 906{
 907	writel(1, spi_imx->base + MXC_RESET);
 908}
 909
 910static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 911	.intctrl = mx1_intctrl,
 912	.prepare_message = mx1_prepare_message,
 913	.prepare_transfer = mx1_prepare_transfer,
 914	.trigger = mx1_trigger,
 915	.rx_available = mx1_rx_available,
 916	.reset = mx1_reset,
 917	.fifo_size = 8,
 918	.has_dmamode = false,
 919	.dynamic_burst = false,
 920	.has_slavemode = false,
 921	.devtype = IMX1_CSPI,
 922};
 923
 924static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 925	.intctrl = mx21_intctrl,
 926	.prepare_message = mx21_prepare_message,
 927	.prepare_transfer = mx21_prepare_transfer,
 928	.trigger = mx21_trigger,
 929	.rx_available = mx21_rx_available,
 930	.reset = mx21_reset,
 931	.fifo_size = 8,
 932	.has_dmamode = false,
 933	.dynamic_burst = false,
 934	.has_slavemode = false,
 935	.devtype = IMX21_CSPI,
 936};
 937
 938static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 939	/* i.mx27 cspi shares the functions with i.mx21 one */
 940	.intctrl = mx21_intctrl,
 941	.prepare_message = mx21_prepare_message,
 942	.prepare_transfer = mx21_prepare_transfer,
 943	.trigger = mx21_trigger,
 944	.rx_available = mx21_rx_available,
 945	.reset = mx21_reset,
 946	.fifo_size = 8,
 947	.has_dmamode = false,
 948	.dynamic_burst = false,
 949	.has_slavemode = false,
 950	.devtype = IMX27_CSPI,
 951};
 952
 953static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 954	.intctrl = mx31_intctrl,
 955	.prepare_message = mx31_prepare_message,
 956	.prepare_transfer = mx31_prepare_transfer,
 957	.trigger = mx31_trigger,
 958	.rx_available = mx31_rx_available,
 959	.reset = mx31_reset,
 960	.fifo_size = 8,
 961	.has_dmamode = false,
 962	.dynamic_burst = false,
 963	.has_slavemode = false,
 964	.devtype = IMX31_CSPI,
 965};
 966
 967static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 968	/* i.mx35 and later cspi shares the functions with i.mx31 one */
 969	.intctrl = mx31_intctrl,
 970	.prepare_message = mx31_prepare_message,
 971	.prepare_transfer = mx31_prepare_transfer,
 972	.trigger = mx31_trigger,
 973	.rx_available = mx31_rx_available,
 974	.reset = mx31_reset,
 975	.fifo_size = 8,
 976	.has_dmamode = true,
 977	.dynamic_burst = false,
 978	.has_slavemode = false,
 979	.devtype = IMX35_CSPI,
 980};
 981
 982static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 983	.intctrl = mx51_ecspi_intctrl,
 984	.prepare_message = mx51_ecspi_prepare_message,
 985	.prepare_transfer = mx51_ecspi_prepare_transfer,
 986	.trigger = mx51_ecspi_trigger,
 987	.rx_available = mx51_ecspi_rx_available,
 988	.reset = mx51_ecspi_reset,
 989	.setup_wml = mx51_setup_wml,
 990	.fifo_size = 64,
 991	.has_dmamode = true,
 992	.dynamic_burst = true,
 993	.has_slavemode = true,
 994	.disable = mx51_ecspi_disable,
 995	.devtype = IMX51_ECSPI,
 996};
 997
 998static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
 999	.intctrl = mx51_ecspi_intctrl,
1000	.prepare_message = mx51_ecspi_prepare_message,
1001	.prepare_transfer = mx51_ecspi_prepare_transfer,
1002	.trigger = mx51_ecspi_trigger,
1003	.rx_available = mx51_ecspi_rx_available,
1004	.reset = mx51_ecspi_reset,
1005	.fifo_size = 64,
1006	.has_dmamode = true,
1007	.has_slavemode = true,
1008	.disable = mx51_ecspi_disable,
1009	.devtype = IMX53_ECSPI,
1010};
1011
1012static const struct platform_device_id spi_imx_devtype[] = {
1013	{
1014		.name = "imx1-cspi",
1015		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
1016	}, {
1017		.name = "imx21-cspi",
1018		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
1019	}, {
1020		.name = "imx27-cspi",
1021		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
1022	}, {
1023		.name = "imx31-cspi",
1024		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
1025	}, {
1026		.name = "imx35-cspi",
1027		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
1028	}, {
1029		.name = "imx51-ecspi",
1030		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
1031	}, {
1032		.name = "imx53-ecspi",
1033		.driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
1034	}, {
1035		/* sentinel */
1036	}
1037};
1038
1039static const struct of_device_id spi_imx_dt_ids[] = {
1040	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1041	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1042	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1043	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1044	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1045	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1046	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1047	{ /* sentinel */ }
1048};
1049MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1050
1051static void spi_imx_chipselect(struct spi_device *spi, int is_active)
1052{
 
 
1053	int active = is_active != BITBANG_CS_INACTIVE;
1054	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
1055
1056	if (spi->mode & SPI_NO_CS)
1057		return;
1058
1059	if (!gpio_is_valid(spi->cs_gpio))
1060		return;
1061
1062	gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
1063}
1064
1065static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1066{
1067	u32 ctrl;
1068
1069	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1070	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1071	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1072	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1073}
1074
1075static void spi_imx_push(struct spi_imx_data *spi_imx)
1076{
1077	unsigned int burst_len, fifo_words;
1078
1079	if (spi_imx->dynamic_burst)
1080		fifo_words = 4;
1081	else
1082		fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1083	/*
1084	 * Reload the FIFO when the remaining bytes to be transferred in the
1085	 * current burst is 0. This only applies when bits_per_word is a
1086	 * multiple of 8.
1087	 */
1088	if (!spi_imx->remainder) {
1089		if (spi_imx->dynamic_burst) {
1090
1091			/* We need to deal unaligned data first */
1092			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1093
1094			if (!burst_len)
1095				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1096
1097			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1098
1099			spi_imx->remainder = burst_len;
1100		} else {
1101			spi_imx->remainder = fifo_words;
1102		}
1103	}
1104
1105	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1106		if (!spi_imx->count)
1107			break;
1108		if (spi_imx->dynamic_burst &&
1109		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1110						     fifo_words))
1111			break;
1112		spi_imx->tx(spi_imx);
1113		spi_imx->txfifo++;
1114	}
1115
1116	if (!spi_imx->slave_mode)
1117		spi_imx->devtype_data->trigger(spi_imx);
1118}
1119
1120static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1121{
1122	struct spi_imx_data *spi_imx = dev_id;
1123
1124	while (spi_imx->txfifo &&
1125	       spi_imx->devtype_data->rx_available(spi_imx)) {
1126		spi_imx->rx(spi_imx);
1127		spi_imx->txfifo--;
1128	}
1129
1130	if (spi_imx->count) {
1131		spi_imx_push(spi_imx);
1132		return IRQ_HANDLED;
1133	}
1134
1135	if (spi_imx->txfifo) {
1136		/* No data left to push, but still waiting for rx data,
1137		 * enable receive data available interrupt.
1138		 */
1139		spi_imx->devtype_data->intctrl(
1140				spi_imx, MXC_INT_RR);
1141		return IRQ_HANDLED;
1142	}
1143
1144	spi_imx->devtype_data->intctrl(spi_imx, 0);
1145	complete(&spi_imx->xfer_done);
1146
1147	return IRQ_HANDLED;
1148}
1149
1150static int spi_imx_dma_configure(struct spi_master *master)
 
1151{
1152	int ret;
1153	enum dma_slave_buswidth buswidth;
1154	struct dma_slave_config rx = {}, tx = {};
1155	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1156
1157	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
 
 
 
 
1158	case 4:
1159		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1160		break;
1161	case 2:
1162		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1163		break;
1164	case 1:
1165		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1166		break;
1167	default:
1168		return -EINVAL;
1169	}
1170
1171	tx.direction = DMA_MEM_TO_DEV;
1172	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1173	tx.dst_addr_width = buswidth;
1174	tx.dst_maxburst = spi_imx->wml;
1175	ret = dmaengine_slave_config(master->dma_tx, &tx);
1176	if (ret) {
1177		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1178		return ret;
1179	}
1180
1181	rx.direction = DMA_DEV_TO_MEM;
1182	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1183	rx.src_addr_width = buswidth;
1184	rx.src_maxburst = spi_imx->wml;
1185	ret = dmaengine_slave_config(master->dma_rx, &rx);
1186	if (ret) {
1187		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1188		return ret;
1189	}
1190
 
 
1191	return 0;
1192}
1193
1194static int spi_imx_setupxfer(struct spi_device *spi,
1195				 struct spi_transfer *t)
1196{
1197	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
 
1198
1199	if (!t)
1200		return 0;
1201
1202	spi_imx->bits_per_word = t->bits_per_word;
1203
1204	/*
1205	 * Initialize the functions for transfer. To transfer non byte-aligned
1206	 * words, we have to use multiple word-size bursts, we can't use
1207	 * dynamic_burst in that case.
1208	 */
1209	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1210	    (spi_imx->bits_per_word == 8 ||
1211	    spi_imx->bits_per_word == 16 ||
1212	    spi_imx->bits_per_word == 32)) {
1213
1214		spi_imx->rx = spi_imx_buf_rx_swap;
1215		spi_imx->tx = spi_imx_buf_tx_swap;
1216		spi_imx->dynamic_burst = 1;
1217
1218	} else {
1219		if (spi_imx->bits_per_word <= 8) {
1220			spi_imx->rx = spi_imx_buf_rx_u8;
1221			spi_imx->tx = spi_imx_buf_tx_u8;
1222		} else if (spi_imx->bits_per_word <= 16) {
1223			spi_imx->rx = spi_imx_buf_rx_u16;
1224			spi_imx->tx = spi_imx_buf_tx_u16;
1225		} else {
1226			spi_imx->rx = spi_imx_buf_rx_u32;
1227			spi_imx->tx = spi_imx_buf_tx_u32;
1228		}
1229		spi_imx->dynamic_burst = 0;
1230	}
1231
1232	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1233		spi_imx->usedma = 1;
1234	else
1235		spi_imx->usedma = 0;
1236
1237	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1238		spi_imx->rx = mx53_ecspi_rx_slave;
1239		spi_imx->tx = mx53_ecspi_tx_slave;
1240		spi_imx->slave_burst = t->len;
 
1241	}
1242
1243	spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
1244
1245	return 0;
1246}
1247
1248static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1249{
1250	struct spi_master *master = spi_imx->bitbang.master;
1251
1252	if (master->dma_rx) {
1253		dma_release_channel(master->dma_rx);
1254		master->dma_rx = NULL;
1255	}
1256
1257	if (master->dma_tx) {
1258		dma_release_channel(master->dma_tx);
1259		master->dma_tx = NULL;
1260	}
1261}
1262
1263static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1264			     struct spi_master *master)
1265{
1266	int ret;
1267
1268	/* use pio mode for i.mx6dl chip TKT238285 */
1269	if (of_machine_is_compatible("fsl,imx6dl"))
1270		return 0;
1271
1272	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1273
1274	/* Prepare for TX DMA: */
1275	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
1276	if (IS_ERR(master->dma_tx)) {
1277		ret = PTR_ERR(master->dma_tx);
1278		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1279		master->dma_tx = NULL;
1280		goto err;
1281	}
1282
1283	/* Prepare for RX : */
1284	master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
1285	if (IS_ERR(master->dma_rx)) {
1286		ret = PTR_ERR(master->dma_rx);
1287		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1288		master->dma_rx = NULL;
1289		goto err;
1290	}
1291
 
 
1292	init_completion(&spi_imx->dma_rx_completion);
1293	init_completion(&spi_imx->dma_tx_completion);
1294	master->can_dma = spi_imx_can_dma;
1295	master->max_dma_len = MAX_SDMA_BD_BYTES;
1296	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1297					 SPI_MASTER_MUST_TX;
1298
1299	return 0;
1300err:
1301	spi_imx_sdma_exit(spi_imx);
1302	return ret;
1303}
1304
1305static void spi_imx_dma_rx_callback(void *cookie)
1306{
1307	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1308
1309	complete(&spi_imx->dma_rx_completion);
1310}
1311
1312static void spi_imx_dma_tx_callback(void *cookie)
1313{
1314	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1315
1316	complete(&spi_imx->dma_tx_completion);
1317}
1318
1319static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1320{
1321	unsigned long timeout = 0;
1322
1323	/* Time with actual data transfer and CS change delay related to HW */
1324	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1325
1326	/* Add extra second for scheduler related activities */
1327	timeout += 1;
1328
1329	/* Double calculated timeout */
1330	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1331}
1332
1333static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1334				struct spi_transfer *transfer)
1335{
1336	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1337	unsigned long transfer_timeout;
1338	unsigned long timeout;
1339	struct spi_master *master = spi_imx->bitbang.master;
1340	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1341	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1342	unsigned int bytes_per_word, i;
1343	int ret;
1344
1345	/* Get the right burst length from the last sg to ensure no tail data */
1346	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1347	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1348		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1349			break;
1350	}
1351	/* Use 1 as wml in case no available burst length got */
1352	if (i == 0)
1353		i = 1;
1354
1355	spi_imx->wml =  i;
1356
1357	ret = spi_imx_dma_configure(master);
1358	if (ret)
1359		return ret;
1360
1361	if (!spi_imx->devtype_data->setup_wml) {
1362		dev_err(spi_imx->dev, "No setup_wml()?\n");
1363		return -EINVAL;
1364	}
1365	spi_imx->devtype_data->setup_wml(spi_imx);
1366
1367	/*
1368	 * The TX DMA setup starts the transfer, so make sure RX is configured
1369	 * before TX.
1370	 */
1371	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1372				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1373				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1374	if (!desc_rx)
1375		return -EINVAL;
1376
1377	desc_rx->callback = spi_imx_dma_rx_callback;
1378	desc_rx->callback_param = (void *)spi_imx;
1379	dmaengine_submit(desc_rx);
1380	reinit_completion(&spi_imx->dma_rx_completion);
1381	dma_async_issue_pending(master->dma_rx);
1382
1383	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1384				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1385				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1386	if (!desc_tx) {
1387		dmaengine_terminate_all(master->dma_tx);
1388		return -EINVAL;
1389	}
1390
1391	desc_tx->callback = spi_imx_dma_tx_callback;
1392	desc_tx->callback_param = (void *)spi_imx;
1393	dmaengine_submit(desc_tx);
1394	reinit_completion(&spi_imx->dma_tx_completion);
1395	dma_async_issue_pending(master->dma_tx);
1396
1397	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1398
1399	/* Wait SDMA to finish the data transfer.*/
1400	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1401						transfer_timeout);
1402	if (!timeout) {
1403		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1404		dmaengine_terminate_all(master->dma_tx);
1405		dmaengine_terminate_all(master->dma_rx);
1406		return -ETIMEDOUT;
1407	}
1408
1409	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1410					      transfer_timeout);
1411	if (!timeout) {
1412		dev_err(&master->dev, "I/O Error in DMA RX\n");
1413		spi_imx->devtype_data->reset(spi_imx);
1414		dmaengine_terminate_all(master->dma_rx);
1415		return -ETIMEDOUT;
1416	}
1417
1418	return transfer->len;
1419}
1420
1421static int spi_imx_pio_transfer(struct spi_device *spi,
1422				struct spi_transfer *transfer)
1423{
1424	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1425	unsigned long transfer_timeout;
1426	unsigned long timeout;
1427
1428	spi_imx->tx_buf = transfer->tx_buf;
1429	spi_imx->rx_buf = transfer->rx_buf;
1430	spi_imx->count = transfer->len;
1431	spi_imx->txfifo = 0;
1432	spi_imx->remainder = 0;
1433
1434	reinit_completion(&spi_imx->xfer_done);
1435
1436	spi_imx_push(spi_imx);
1437
1438	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1439
1440	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1441
1442	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1443					      transfer_timeout);
1444	if (!timeout) {
1445		dev_err(&spi->dev, "I/O Error in PIO\n");
1446		spi_imx->devtype_data->reset(spi_imx);
1447		return -ETIMEDOUT;
1448	}
1449
1450	return transfer->len;
1451}
1452
1453static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1454				      struct spi_transfer *transfer)
1455{
1456	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1457	int ret = transfer->len;
1458
1459	if (is_imx53_ecspi(spi_imx) &&
1460	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1461		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1462			MX53_MAX_TRANSFER_BYTES);
1463		return -EMSGSIZE;
1464	}
1465
1466	spi_imx->tx_buf = transfer->tx_buf;
1467	spi_imx->rx_buf = transfer->rx_buf;
1468	spi_imx->count = transfer->len;
1469	spi_imx->txfifo = 0;
1470	spi_imx->remainder = 0;
1471
1472	reinit_completion(&spi_imx->xfer_done);
1473	spi_imx->slave_aborted = false;
1474
1475	spi_imx_push(spi_imx);
1476
1477	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1478
1479	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1480	    spi_imx->slave_aborted) {
1481		dev_dbg(&spi->dev, "interrupted\n");
1482		ret = -EINTR;
1483	}
1484
1485	/* ecspi has a HW issue when works in Slave mode,
1486	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1487	 * ECSPI_TXDATA keeps shift out the last word data,
1488	 * so we have to disable ECSPI when in slave mode after the
1489	 * transfer completes
1490	 */
1491	if (spi_imx->devtype_data->disable)
1492		spi_imx->devtype_data->disable(spi_imx);
1493
1494	return ret;
1495}
1496
1497static int spi_imx_transfer(struct spi_device *spi,
1498				struct spi_transfer *transfer)
1499{
1500	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1501
1502	/* flush rxfifo before transfer */
1503	while (spi_imx->devtype_data->rx_available(spi_imx))
1504		readl(spi_imx->base + MXC_CSPIRXDATA);
1505
1506	if (spi_imx->slave_mode)
1507		return spi_imx_pio_transfer_slave(spi, transfer);
1508
1509	if (spi_imx->usedma)
1510		return spi_imx_dma_transfer(spi_imx, transfer);
1511	else
1512		return spi_imx_pio_transfer(spi, transfer);
1513}
1514
1515static int spi_imx_setup(struct spi_device *spi)
1516{
 
 
 
1517	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1518		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1519
1520	if (spi->mode & SPI_NO_CS)
1521		return 0;
1522
1523	if (gpio_is_valid(spi->cs_gpio))
1524		gpio_direction_output(spi->cs_gpio,
1525				      spi->mode & SPI_CS_HIGH ? 0 : 1);
1526
1527	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1528
1529	return 0;
1530}
1531
1532static void spi_imx_cleanup(struct spi_device *spi)
1533{
1534}
1535
1536static int
1537spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1538{
1539	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1540	int ret;
1541
1542	ret = clk_enable(spi_imx->clk_per);
1543	if (ret)
1544		return ret;
1545
1546	ret = clk_enable(spi_imx->clk_ipg);
1547	if (ret) {
1548		clk_disable(spi_imx->clk_per);
1549		return ret;
1550	}
1551
1552	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1553	if (ret) {
1554		clk_disable(spi_imx->clk_ipg);
1555		clk_disable(spi_imx->clk_per);
1556	}
1557
1558	return ret;
1559}
1560
1561static int
1562spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1563{
1564	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1565
1566	clk_disable(spi_imx->clk_ipg);
1567	clk_disable(spi_imx->clk_per);
1568	return 0;
1569}
1570
1571static int spi_imx_slave_abort(struct spi_master *master)
1572{
1573	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1574
1575	spi_imx->slave_aborted = true;
1576	complete(&spi_imx->xfer_done);
1577
1578	return 0;
1579}
1580
1581static int spi_imx_probe(struct platform_device *pdev)
1582{
1583	struct device_node *np = pdev->dev.of_node;
1584	const struct of_device_id *of_id =
1585			of_match_device(spi_imx_dt_ids, &pdev->dev);
1586	struct spi_imx_master *mxc_platform_info =
1587			dev_get_platdata(&pdev->dev);
1588	struct spi_master *master;
1589	struct spi_imx_data *spi_imx;
1590	struct resource *res;
1591	int i, ret, irq, spi_drctl;
1592	const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
1593		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1594	bool slave_mode;
1595
1596	if (!np && !mxc_platform_info) {
1597		dev_err(&pdev->dev, "can't get the platform data\n");
1598		return -EINVAL;
1599	}
1600
1601	slave_mode = devtype_data->has_slavemode &&
1602			of_property_read_bool(np, "spi-slave");
1603	if (slave_mode)
1604		master = spi_alloc_slave(&pdev->dev,
1605					 sizeof(struct spi_imx_data));
1606	else
1607		master = spi_alloc_master(&pdev->dev,
1608					  sizeof(struct spi_imx_data));
 
 
1609	if (!master)
1610		return -ENOMEM;
1611
1612	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1613	if ((ret < 0) || (spi_drctl >= 0x3)) {
1614		/* '11' is reserved */
1615		spi_drctl = 0;
1616	}
1617
1618	platform_set_drvdata(pdev, master);
1619
1620	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1621	master->bus_num = np ? -1 : pdev->id;
 
1622
1623	spi_imx = spi_master_get_devdata(master);
1624	spi_imx->bitbang.master = master;
1625	spi_imx->dev = &pdev->dev;
1626	spi_imx->slave_mode = slave_mode;
1627
1628	spi_imx->devtype_data = devtype_data;
1629
1630	/* Get number of chip selects, either platform data or OF */
1631	if (mxc_platform_info) {
1632		master->num_chipselect = mxc_platform_info->num_chipselect;
1633		if (mxc_platform_info->chipselect) {
1634			master->cs_gpios = devm_kcalloc(&master->dev,
1635				master->num_chipselect, sizeof(int),
1636				GFP_KERNEL);
1637			if (!master->cs_gpios)
1638				return -ENOMEM;
1639
1640			for (i = 0; i < master->num_chipselect; i++)
1641				master->cs_gpios[i] = mxc_platform_info->chipselect[i];
 
 
 
 
 
 
 
 
 
 
 
 
1642		}
1643	} else {
1644		u32 num_cs;
1645
1646		if (!of_property_read_u32(np, "num-cs", &num_cs))
1647			master->num_chipselect = num_cs;
1648		/* If not preset, default value of 1 is used */
1649	}
1650
1651	spi_imx->bitbang.chipselect = spi_imx_chipselect;
1652	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1653	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1654	spi_imx->bitbang.master->setup = spi_imx_setup;
1655	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1656	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1657	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1658	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1659	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1660					     | SPI_NO_CS;
1661	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1662	    is_imx53_ecspi(spi_imx))
1663		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1664
1665	spi_imx->spi_drctl = spi_drctl;
1666
1667	init_completion(&spi_imx->xfer_done);
1668
1669	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1670	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1671	if (IS_ERR(spi_imx->base)) {
1672		ret = PTR_ERR(spi_imx->base);
1673		goto out_master_put;
1674	}
1675	spi_imx->base_phys = res->start;
1676
1677	irq = platform_get_irq(pdev, 0);
1678	if (irq < 0) {
1679		ret = irq;
1680		goto out_master_put;
1681	}
1682
1683	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1684			       dev_name(&pdev->dev), spi_imx);
1685	if (ret) {
1686		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1687		goto out_master_put;
1688	}
1689
1690	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1691	if (IS_ERR(spi_imx->clk_ipg)) {
1692		ret = PTR_ERR(spi_imx->clk_ipg);
1693		goto out_master_put;
1694	}
1695
1696	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1697	if (IS_ERR(spi_imx->clk_per)) {
1698		ret = PTR_ERR(spi_imx->clk_per);
1699		goto out_master_put;
1700	}
1701
1702	ret = clk_prepare_enable(spi_imx->clk_per);
1703	if (ret)
1704		goto out_master_put;
1705
1706	ret = clk_prepare_enable(spi_imx->clk_ipg);
1707	if (ret)
1708		goto out_put_per;
1709
1710	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1711	/*
1712	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1713	 * if validated on other chips.
1714	 */
1715	if (spi_imx->devtype_data->has_dmamode) {
1716		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1717		if (ret == -EPROBE_DEFER)
1718			goto out_clk_put;
1719
1720		if (ret < 0)
1721			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1722				ret);
1723	}
1724
1725	spi_imx->devtype_data->reset(spi_imx);
1726
1727	spi_imx->devtype_data->intctrl(spi_imx, 0);
1728
1729	master->dev.of_node = pdev->dev.of_node;
1730	ret = spi_bitbang_start(&spi_imx->bitbang);
1731	if (ret) {
1732		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1733		goto out_clk_put;
1734	}
1735
1736	/* Request GPIO CS lines, if any */
1737	if (!spi_imx->slave_mode && master->cs_gpios) {
1738		for (i = 0; i < master->num_chipselect; i++) {
1739			if (!gpio_is_valid(master->cs_gpios[i]))
1740				continue;
1741
1742			ret = devm_gpio_request(&pdev->dev,
1743						master->cs_gpios[i],
1744						DRIVER_NAME);
1745			if (ret) {
1746				dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
1747					master->cs_gpios[i]);
1748				goto out_spi_bitbang;
1749			}
1750		}
1751	}
1752
1753	dev_info(&pdev->dev, "probed\n");
1754
1755	clk_disable(spi_imx->clk_ipg);
1756	clk_disable(spi_imx->clk_per);
1757	return ret;
1758
1759out_spi_bitbang:
1760	spi_bitbang_stop(&spi_imx->bitbang);
1761out_clk_put:
1762	clk_disable_unprepare(spi_imx->clk_ipg);
1763out_put_per:
1764	clk_disable_unprepare(spi_imx->clk_per);
1765out_master_put:
1766	spi_master_put(master);
1767
1768	return ret;
1769}
1770
1771static int spi_imx_remove(struct platform_device *pdev)
1772{
1773	struct spi_master *master = platform_get_drvdata(pdev);
1774	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1775	int ret;
1776
1777	spi_bitbang_stop(&spi_imx->bitbang);
1778
1779	ret = clk_enable(spi_imx->clk_per);
1780	if (ret)
1781		return ret;
1782
1783	ret = clk_enable(spi_imx->clk_ipg);
1784	if (ret) {
1785		clk_disable(spi_imx->clk_per);
1786		return ret;
1787	}
1788
1789	writel(0, spi_imx->base + MXC_CSPICTRL);
1790	clk_disable_unprepare(spi_imx->clk_ipg);
1791	clk_disable_unprepare(spi_imx->clk_per);
1792	spi_imx_sdma_exit(spi_imx);
1793	spi_master_put(master);
1794
1795	return 0;
1796}
1797
1798static struct platform_driver spi_imx_driver = {
1799	.driver = {
1800		   .name = DRIVER_NAME,
1801		   .of_match_table = spi_imx_dt_ids,
1802		   },
1803	.id_table = spi_imx_devtype,
1804	.probe = spi_imx_probe,
1805	.remove = spi_imx_remove,
1806};
1807module_platform_driver(spi_imx_driver);
1808
1809MODULE_DESCRIPTION("SPI Controller driver");
1810MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1811MODULE_LICENSE("GPL");
1812MODULE_ALIAS("platform:" DRIVER_NAME);
v4.6
   1/*
   2 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3 * Copyright (C) 2008 Juergen Beisert
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License
   7 * as published by the Free Software Foundation; either version 2
   8 * of the License, or (at your option) any later version.
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write to the
  16 * Free Software Foundation
  17 * 51 Franklin Street, Fifth Floor
  18 * Boston, MA  02110-1301, USA.
  19 */
  20
  21#include <linux/clk.h>
  22#include <linux/completion.h>
  23#include <linux/delay.h>
  24#include <linux/dmaengine.h>
  25#include <linux/dma-mapping.h>
  26#include <linux/err.h>
  27#include <linux/gpio.h>
  28#include <linux/interrupt.h>
  29#include <linux/io.h>
  30#include <linux/irq.h>
  31#include <linux/kernel.h>
  32#include <linux/module.h>
  33#include <linux/platform_device.h>
  34#include <linux/slab.h>
  35#include <linux/spi/spi.h>
  36#include <linux/spi/spi_bitbang.h>
  37#include <linux/types.h>
  38#include <linux/of.h>
  39#include <linux/of_device.h>
  40#include <linux/of_gpio.h>
  41
  42#include <linux/platform_data/dma-imx.h>
  43#include <linux/platform_data/spi-imx.h>
  44
  45#define DRIVER_NAME "spi_imx"
  46
 
 
 
 
  47#define MXC_CSPIRXDATA		0x00
  48#define MXC_CSPITXDATA		0x04
  49#define MXC_CSPICTRL		0x08
  50#define MXC_CSPIINT		0x0c
  51#define MXC_RESET		0x1c
  52
  53/* generic defines to abstract from the different register layouts */
  54#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
  55#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
 
  56
  57/* The maximum  bytes that a sdma BD can transfer.*/
  58#define MAX_SDMA_BD_BYTES  (1 << 15)
  59struct spi_imx_config {
  60	unsigned int speed_hz;
  61	unsigned int bpw;
  62	unsigned int mode;
  63	u8 cs;
  64};
  65
  66enum spi_imx_devtype {
  67	IMX1_CSPI,
  68	IMX21_CSPI,
  69	IMX27_CSPI,
  70	IMX31_CSPI,
  71	IMX35_CSPI,	/* CSPI on all i.mx except above */
  72	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
 
  73};
  74
  75struct spi_imx_data;
  76
  77struct spi_imx_devtype_data {
  78	void (*intctrl)(struct spi_imx_data *, int);
  79	int (*config)(struct spi_imx_data *, struct spi_imx_config *);
 
 
  80	void (*trigger)(struct spi_imx_data *);
  81	int (*rx_available)(struct spi_imx_data *);
  82	void (*reset)(struct spi_imx_data *);
 
 
 
 
 
 
  83	enum spi_imx_devtype devtype;
  84};
  85
  86struct spi_imx_data {
  87	struct spi_bitbang bitbang;
  88	struct device *dev;
  89
  90	struct completion xfer_done;
  91	void __iomem *base;
  92	unsigned long base_phys;
  93
  94	struct clk *clk_per;
  95	struct clk *clk_ipg;
  96	unsigned long spi_clk;
  97	unsigned int spi_bus_clk;
  98
  99	unsigned int bytes_per_word;
 
 100
 101	unsigned int count;
 102	void (*tx)(struct spi_imx_data *);
 103	void (*rx)(struct spi_imx_data *);
 104	void *rx_buf;
 105	const void *tx_buf;
 106	unsigned int txfifo; /* number of words pushed in tx FIFO */
 
 
 
 
 
 
 107
 108	/* DMA */
 109	bool usedma;
 110	u32 wml;
 111	struct completion dma_rx_completion;
 112	struct completion dma_tx_completion;
 113
 114	const struct spi_imx_devtype_data *devtype_data;
 115	int chipselect[0];
 116};
 117
 118static inline int is_imx27_cspi(struct spi_imx_data *d)
 119{
 120	return d->devtype_data->devtype == IMX27_CSPI;
 121}
 122
 123static inline int is_imx35_cspi(struct spi_imx_data *d)
 124{
 125	return d->devtype_data->devtype == IMX35_CSPI;
 126}
 127
 128static inline int is_imx51_ecspi(struct spi_imx_data *d)
 129{
 130	return d->devtype_data->devtype == IMX51_ECSPI;
 131}
 132
 133static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
 134{
 135	return is_imx51_ecspi(d) ? 64 : 8;
 136}
 137
 138#define MXC_SPI_BUF_RX(type)						\
 139static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 140{									\
 141	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 142									\
 143	if (spi_imx->rx_buf) {						\
 144		*(type *)spi_imx->rx_buf = val;				\
 145		spi_imx->rx_buf += sizeof(type);			\
 146	}								\
 
 
 147}
 148
 149#define MXC_SPI_BUF_TX(type)						\
 150static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 151{									\
 152	type val = 0;							\
 153									\
 154	if (spi_imx->tx_buf) {						\
 155		val = *(type *)spi_imx->tx_buf;				\
 156		spi_imx->tx_buf += sizeof(type);			\
 157	}								\
 158									\
 159	spi_imx->count -= sizeof(type);					\
 160									\
 161	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 162}
 163
 164MXC_SPI_BUF_RX(u8)
 165MXC_SPI_BUF_TX(u8)
 166MXC_SPI_BUF_RX(u16)
 167MXC_SPI_BUF_TX(u16)
 168MXC_SPI_BUF_RX(u32)
 169MXC_SPI_BUF_TX(u32)
 170
 171/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 172 * (which is currently not the case in this driver)
 173 */
 174static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 175	256, 384, 512, 768, 1024};
 176
 177/* MX21, MX27 */
 178static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 179		unsigned int fspi, unsigned int max)
 180{
 181	int i;
 182
 183	for (i = 2; i < max; i++)
 184		if (fspi * mxc_clkdivs[i] >= fin)
 185			return i;
 186
 187	return max;
 
 188}
 189
 190/* MX1, MX31, MX35, MX51 CSPI */
 191static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 192		unsigned int fspi)
 193{
 194	int i, div = 4;
 195
 196	for (i = 0; i < 7; i++) {
 197		if (fspi * div >= fin)
 198			return i;
 199		div <<= 1;
 200	}
 201
 202	return 7;
 
 
 203}
 204
 205static int spi_imx_bytes_per_word(const int bpw)
 206{
 207	return DIV_ROUND_UP(bpw, BITS_PER_BYTE);
 
 
 
 
 
 208}
 209
 210static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 211			 struct spi_transfer *transfer)
 212{
 213	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 214	unsigned int bpw;
 215
 216	if (!master->dma_rx)
 217		return false;
 218
 219	if (!transfer)
 220		return false;
 221
 222	bpw = transfer->bits_per_word;
 223	if (!bpw)
 224		bpw = spi->bits_per_word;
 225
 226	bpw = spi_imx_bytes_per_word(bpw);
 227
 228	if (bpw != 1 && bpw != 2 && bpw != 4)
 229		return false;
 230
 231	if (transfer->len < spi_imx->wml * bpw)
 232		return false;
 233
 234	if (transfer->len % (spi_imx->wml * bpw))
 235		return false;
 236
 237	return true;
 238}
 239
 240#define MX51_ECSPI_CTRL		0x08
 241#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
 242#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 243#define MX51_ECSPI_CTRL_SMC		(1 << 3)
 244#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 
 245#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
 246#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 247#define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
 248#define MX51_ECSPI_CTRL_BL_OFFSET	20
 
 249
 250#define MX51_ECSPI_CONFIG	0x0c
 251#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
 252#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
 253#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
 254#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
 255#define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
 256
 257#define MX51_ECSPI_INT		0x10
 258#define MX51_ECSPI_INT_TEEN		(1 <<  0)
 259#define MX51_ECSPI_INT_RREN		(1 <<  3)
 
 260
 261#define MX51_ECSPI_DMA      0x14
 262#define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
 263#define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
 264#define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
 265
 266#define MX51_ECSPI_DMA_TEDEN		(1 << 7)
 267#define MX51_ECSPI_DMA_RXDEN		(1 << 23)
 268#define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
 269
 270#define MX51_ECSPI_STAT		0x18
 271#define MX51_ECSPI_STAT_RR		(1 <<  3)
 272
 273#define MX51_ECSPI_TESTREG	0x20
 274#define MX51_ECSPI_TESTREG_LBC	BIT(31)
 275
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 276/* MX51 eCSPI */
 277static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 278				      unsigned int fspi, unsigned int *fres)
 279{
 280	/*
 281	 * there are two 4-bit dividers, the pre-divider divides by
 282	 * $pre, the post-divider by 2^$post
 283	 */
 284	unsigned int pre, post;
 285	unsigned int fin = spi_imx->spi_clk;
 286
 287	if (unlikely(fspi > fin))
 288		return 0;
 289
 290	post = fls(fin) - fls(fspi);
 291	if (fin > fspi << post)
 292		post++;
 293
 294	/* now we have: (fin <= fspi << post) with post being minimal */
 295
 296	post = max(4U, post) - 4;
 297	if (unlikely(post > 0xf)) {
 298		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 299				fspi, fin);
 300		return 0xff;
 301	}
 302
 303	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 304
 305	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 306			__func__, fin, fspi, post, pre);
 307
 308	/* Resulting frequency for the SCLK line. */
 309	*fres = (fin / (pre + 1)) >> post;
 310
 311	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 312		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 313}
 314
 315static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 316{
 317	unsigned val = 0;
 318
 319	if (enable & MXC_INT_TE)
 320		val |= MX51_ECSPI_INT_TEEN;
 321
 322	if (enable & MXC_INT_RR)
 323		val |= MX51_ECSPI_INT_RREN;
 324
 
 
 
 325	writel(val, spi_imx->base + MX51_ECSPI_INT);
 326}
 327
 328static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 329{
 330	u32 reg;
 331
 332	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 333	reg |= MX51_ECSPI_CTRL_XCH;
 334	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 335}
 336
 337static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
 338		struct spi_imx_config *config)
 339{
 
 
 
 
 
 
 
 
 
 
 
 340	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 341	u32 clk = config->speed_hz, delay, reg;
 342	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 343
 
 
 
 
 
 
 344	/*
 345	 * The hardware seems to have a race condition when changing modes. The
 346	 * current assumption is that the selection of the channel arrives
 347	 * earlier in the hardware than the mode bits when they are written at
 348	 * the same time.
 349	 * So set master mode for all channels as we do not support slave mode.
 350	 */
 351	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 
 352
 353	/* set clock speed */
 354	ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk);
 355	spi_imx->spi_bus_clk = clk;
 356
 357	/* set chip select to use */
 358	ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
 
 
 
 359
 360	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
 
 
 
 
 
 361
 362	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
 
 
 
 
 
 
 
 
 363
 364	if (config->mode & SPI_CPHA)
 365		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
 366	else
 367		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
 368
 369	if (config->mode & SPI_CPOL) {
 370		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
 371		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
 372	} else {
 373		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
 374		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
 375	}
 376	if (config->mode & SPI_CS_HIGH)
 377		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
 
 378	else
 379		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(config->cs);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 380
 381	if (spi_imx->usedma)
 382		ctrl |= MX51_ECSPI_CTRL_SMC;
 383
 384	/* CTRL register always go first to bring out controller from reset */
 385	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 386
 387	reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 388	if (config->mode & SPI_LOOP)
 389		reg |= MX51_ECSPI_TESTREG_LBC;
 390	else
 391		reg &= ~MX51_ECSPI_TESTREG_LBC;
 392	writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
 393
 394	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 395
 396	/*
 397	 * Wait until the changes in the configuration register CONFIGREG
 398	 * propagate into the hardware. It takes exactly one tick of the
 399	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 400	 * effect of the delay it takes for the hardware to apply changes
 401	 * is noticable if the SCLK clock run very slow. In such a case, if
 402	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 403	 * be asserted before the SCLK polarity changes, which would disrupt
 404	 * the SPI communication as the device on the other end would consider
 405	 * the change of SCLK polarity as a clock tick already.
 406	 */
 407	delay = (2 * 1000000) / clk;
 408	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
 409		udelay(delay);
 410	else			/* SCLK is _very_ slow */
 411		usleep_range(delay, delay + 10);
 412
 
 
 
 
 
 413	/*
 414	 * Configure the DMA register: setup the watermark
 415	 * and enable DMA request.
 416	 */
 417
 418	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
 419		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 420		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 421		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 422		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 423
 424	return 0;
 425}
 426
 427static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 428{
 429	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 430}
 431
 432static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 433{
 434	/* drain receive buffer */
 435	while (mx51_ecspi_rx_available(spi_imx))
 436		readl(spi_imx->base + MXC_CSPIRXDATA);
 437}
 438
 439#define MX31_INTREG_TEEN	(1 << 0)
 440#define MX31_INTREG_RREN	(1 << 3)
 441
 442#define MX31_CSPICTRL_ENABLE	(1 << 0)
 443#define MX31_CSPICTRL_MASTER	(1 << 1)
 444#define MX31_CSPICTRL_XCH	(1 << 2)
 
 445#define MX31_CSPICTRL_POL	(1 << 4)
 446#define MX31_CSPICTRL_PHA	(1 << 5)
 447#define MX31_CSPICTRL_SSCTL	(1 << 6)
 448#define MX31_CSPICTRL_SSPOL	(1 << 7)
 449#define MX31_CSPICTRL_BC_SHIFT	8
 450#define MX35_CSPICTRL_BL_SHIFT	20
 451#define MX31_CSPICTRL_CS_SHIFT	24
 452#define MX35_CSPICTRL_CS_SHIFT	12
 453#define MX31_CSPICTRL_DR_SHIFT	16
 454
 
 
 
 
 455#define MX31_CSPISTATUS		0x14
 456#define MX31_STATUS_RR		(1 << 3)
 457
 
 
 
 458/* These functions also work for the i.MX35, but be aware that
 459 * the i.MX35 has a slightly different register layout for bits
 460 * we do not use here.
 461 */
 462static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 463{
 464	unsigned int val = 0;
 465
 466	if (enable & MXC_INT_TE)
 467		val |= MX31_INTREG_TEEN;
 468	if (enable & MXC_INT_RR)
 469		val |= MX31_INTREG_RREN;
 470
 471	writel(val, spi_imx->base + MXC_CSPIINT);
 472}
 473
 474static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
 475{
 476	unsigned int reg;
 477
 478	reg = readl(spi_imx->base + MXC_CSPICTRL);
 479	reg |= MX31_CSPICTRL_XCH;
 480	writel(reg, spi_imx->base + MXC_CSPICTRL);
 481}
 482
 483static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
 484		struct spi_imx_config *config)
 
 
 
 
 
 
 
 485{
 486	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 487	int cs = spi_imx->chipselect[config->cs];
 488
 489	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 490		MX31_CSPICTRL_DR_SHIFT;
 
 491
 492	if (is_imx35_cspi(spi_imx)) {
 493		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
 494		reg |= MX31_CSPICTRL_SSCTL;
 495	} else {
 496		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
 497	}
 498
 499	if (config->mode & SPI_CPHA)
 500		reg |= MX31_CSPICTRL_PHA;
 501	if (config->mode & SPI_CPOL)
 502		reg |= MX31_CSPICTRL_POL;
 503	if (config->mode & SPI_CS_HIGH)
 504		reg |= MX31_CSPICTRL_SSPOL;
 505	if (cs < 0)
 506		reg |= (cs + 32) <<
 507			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 508						  MX31_CSPICTRL_CS_SHIFT);
 509
 
 
 
 510	writel(reg, spi_imx->base + MXC_CSPICTRL);
 511
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 512	return 0;
 513}
 514
 515static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
 516{
 517	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 518}
 519
 520static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
 521{
 522	/* drain receive buffer */
 523	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 524		readl(spi_imx->base + MXC_CSPIRXDATA);
 525}
 526
 527#define MX21_INTREG_RR		(1 << 4)
 528#define MX21_INTREG_TEEN	(1 << 9)
 529#define MX21_INTREG_RREN	(1 << 13)
 530
 531#define MX21_CSPICTRL_POL	(1 << 5)
 532#define MX21_CSPICTRL_PHA	(1 << 6)
 533#define MX21_CSPICTRL_SSPOL	(1 << 8)
 534#define MX21_CSPICTRL_XCH	(1 << 9)
 535#define MX21_CSPICTRL_ENABLE	(1 << 10)
 536#define MX21_CSPICTRL_MASTER	(1 << 11)
 537#define MX21_CSPICTRL_DR_SHIFT	14
 538#define MX21_CSPICTRL_CS_SHIFT	19
 539
 540static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 541{
 542	unsigned int val = 0;
 543
 544	if (enable & MXC_INT_TE)
 545		val |= MX21_INTREG_TEEN;
 546	if (enable & MXC_INT_RR)
 547		val |= MX21_INTREG_RREN;
 548
 549	writel(val, spi_imx->base + MXC_CSPIINT);
 550}
 551
 552static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
 553{
 554	unsigned int reg;
 555
 556	reg = readl(spi_imx->base + MXC_CSPICTRL);
 557	reg |= MX21_CSPICTRL_XCH;
 558	writel(reg, spi_imx->base + MXC_CSPICTRL);
 559}
 560
 561static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
 562		struct spi_imx_config *config)
 
 
 
 
 
 
 
 563{
 564	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 565	int cs = spi_imx->chipselect[config->cs];
 566	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 
 
 
 
 
 567
 568	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
 569		MX21_CSPICTRL_DR_SHIFT;
 570	reg |= config->bpw - 1;
 571
 572	if (config->mode & SPI_CPHA)
 573		reg |= MX21_CSPICTRL_PHA;
 574	if (config->mode & SPI_CPOL)
 575		reg |= MX21_CSPICTRL_POL;
 576	if (config->mode & SPI_CS_HIGH)
 577		reg |= MX21_CSPICTRL_SSPOL;
 578	if (cs < 0)
 579		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
 580
 581	writel(reg, spi_imx->base + MXC_CSPICTRL);
 582
 583	return 0;
 584}
 585
 586static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
 587{
 588	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 589}
 590
 591static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
 592{
 593	writel(1, spi_imx->base + MXC_RESET);
 594}
 595
 596#define MX1_INTREG_RR		(1 << 3)
 597#define MX1_INTREG_TEEN		(1 << 8)
 598#define MX1_INTREG_RREN		(1 << 11)
 599
 600#define MX1_CSPICTRL_POL	(1 << 4)
 601#define MX1_CSPICTRL_PHA	(1 << 5)
 602#define MX1_CSPICTRL_XCH	(1 << 8)
 603#define MX1_CSPICTRL_ENABLE	(1 << 9)
 604#define MX1_CSPICTRL_MASTER	(1 << 10)
 605#define MX1_CSPICTRL_DR_SHIFT	13
 606
 607static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 608{
 609	unsigned int val = 0;
 610
 611	if (enable & MXC_INT_TE)
 612		val |= MX1_INTREG_TEEN;
 613	if (enable & MXC_INT_RR)
 614		val |= MX1_INTREG_RREN;
 615
 616	writel(val, spi_imx->base + MXC_CSPIINT);
 617}
 618
 619static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
 620{
 621	unsigned int reg;
 622
 623	reg = readl(spi_imx->base + MXC_CSPICTRL);
 624	reg |= MX1_CSPICTRL_XCH;
 625	writel(reg, spi_imx->base + MXC_CSPICTRL);
 626}
 627
 628static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
 629		struct spi_imx_config *config)
 
 
 
 
 
 
 
 630{
 631	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 
 632
 633	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 634		MX1_CSPICTRL_DR_SHIFT;
 635	reg |= config->bpw - 1;
 636
 637	if (config->mode & SPI_CPHA)
 
 
 638		reg |= MX1_CSPICTRL_PHA;
 639	if (config->mode & SPI_CPOL)
 640		reg |= MX1_CSPICTRL_POL;
 641
 642	writel(reg, spi_imx->base + MXC_CSPICTRL);
 643
 644	return 0;
 645}
 646
 647static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
 648{
 649	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 650}
 651
 652static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
 653{
 654	writel(1, spi_imx->base + MXC_RESET);
 655}
 656
 657static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 658	.intctrl = mx1_intctrl,
 659	.config = mx1_config,
 
 660	.trigger = mx1_trigger,
 661	.rx_available = mx1_rx_available,
 662	.reset = mx1_reset,
 
 
 
 
 663	.devtype = IMX1_CSPI,
 664};
 665
 666static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 667	.intctrl = mx21_intctrl,
 668	.config = mx21_config,
 
 669	.trigger = mx21_trigger,
 670	.rx_available = mx21_rx_available,
 671	.reset = mx21_reset,
 
 
 
 
 672	.devtype = IMX21_CSPI,
 673};
 674
 675static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 676	/* i.mx27 cspi shares the functions with i.mx21 one */
 677	.intctrl = mx21_intctrl,
 678	.config = mx21_config,
 
 679	.trigger = mx21_trigger,
 680	.rx_available = mx21_rx_available,
 681	.reset = mx21_reset,
 
 
 
 
 682	.devtype = IMX27_CSPI,
 683};
 684
 685static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 686	.intctrl = mx31_intctrl,
 687	.config = mx31_config,
 
 688	.trigger = mx31_trigger,
 689	.rx_available = mx31_rx_available,
 690	.reset = mx31_reset,
 
 
 
 
 691	.devtype = IMX31_CSPI,
 692};
 693
 694static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 695	/* i.mx35 and later cspi shares the functions with i.mx31 one */
 696	.intctrl = mx31_intctrl,
 697	.config = mx31_config,
 
 698	.trigger = mx31_trigger,
 699	.rx_available = mx31_rx_available,
 700	.reset = mx31_reset,
 
 
 
 
 701	.devtype = IMX35_CSPI,
 702};
 703
 704static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 705	.intctrl = mx51_ecspi_intctrl,
 706	.config = mx51_ecspi_config,
 
 707	.trigger = mx51_ecspi_trigger,
 708	.rx_available = mx51_ecspi_rx_available,
 709	.reset = mx51_ecspi_reset,
 
 
 
 
 
 
 710	.devtype = IMX51_ECSPI,
 711};
 712
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 713static const struct platform_device_id spi_imx_devtype[] = {
 714	{
 715		.name = "imx1-cspi",
 716		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
 717	}, {
 718		.name = "imx21-cspi",
 719		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
 720	}, {
 721		.name = "imx27-cspi",
 722		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
 723	}, {
 724		.name = "imx31-cspi",
 725		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
 726	}, {
 727		.name = "imx35-cspi",
 728		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
 729	}, {
 730		.name = "imx51-ecspi",
 731		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
 732	}, {
 
 
 
 733		/* sentinel */
 734	}
 735};
 736
 737static const struct of_device_id spi_imx_dt_ids[] = {
 738	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
 739	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
 740	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
 741	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
 742	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
 743	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
 
 744	{ /* sentinel */ }
 745};
 746MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
 747
 748static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 749{
 750	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 751	int gpio = spi_imx->chipselect[spi->chip_select];
 752	int active = is_active != BITBANG_CS_INACTIVE;
 753	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
 754
 755	if (!gpio_is_valid(gpio))
 756		return;
 757
 758	gpio_set_value(gpio, dev_is_lowactive ^ active);
 
 
 
 
 
 
 
 
 
 
 
 
 
 759}
 760
 761static void spi_imx_push(struct spi_imx_data *spi_imx)
 762{
 763	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 764		if (!spi_imx->count)
 765			break;
 
 
 
 
 766		spi_imx->tx(spi_imx);
 767		spi_imx->txfifo++;
 768	}
 769
 770	spi_imx->devtype_data->trigger(spi_imx);
 
 771}
 772
 773static irqreturn_t spi_imx_isr(int irq, void *dev_id)
 774{
 775	struct spi_imx_data *spi_imx = dev_id;
 776
 777	while (spi_imx->devtype_data->rx_available(spi_imx)) {
 
 778		spi_imx->rx(spi_imx);
 779		spi_imx->txfifo--;
 780	}
 781
 782	if (spi_imx->count) {
 783		spi_imx_push(spi_imx);
 784		return IRQ_HANDLED;
 785	}
 786
 787	if (spi_imx->txfifo) {
 788		/* No data left to push, but still waiting for rx data,
 789		 * enable receive data available interrupt.
 790		 */
 791		spi_imx->devtype_data->intctrl(
 792				spi_imx, MXC_INT_RR);
 793		return IRQ_HANDLED;
 794	}
 795
 796	spi_imx->devtype_data->intctrl(spi_imx, 0);
 797	complete(&spi_imx->xfer_done);
 798
 799	return IRQ_HANDLED;
 800}
 801
 802static int spi_imx_dma_configure(struct spi_master *master,
 803				 int bytes_per_word)
 804{
 805	int ret;
 806	enum dma_slave_buswidth buswidth;
 807	struct dma_slave_config rx = {}, tx = {};
 808	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 809
 810	if (bytes_per_word == spi_imx->bytes_per_word)
 811		/* Same as last time */
 812		return 0;
 813
 814	switch (bytes_per_word) {
 815	case 4:
 816		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 817		break;
 818	case 2:
 819		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
 820		break;
 821	case 1:
 822		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
 823		break;
 824	default:
 825		return -EINVAL;
 826	}
 827
 828	tx.direction = DMA_MEM_TO_DEV;
 829	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
 830	tx.dst_addr_width = buswidth;
 831	tx.dst_maxburst = spi_imx->wml;
 832	ret = dmaengine_slave_config(master->dma_tx, &tx);
 833	if (ret) {
 834		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
 835		return ret;
 836	}
 837
 838	rx.direction = DMA_DEV_TO_MEM;
 839	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
 840	rx.src_addr_width = buswidth;
 841	rx.src_maxburst = spi_imx->wml;
 842	ret = dmaengine_slave_config(master->dma_rx, &rx);
 843	if (ret) {
 844		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
 845		return ret;
 846	}
 847
 848	spi_imx->bytes_per_word = bytes_per_word;
 849
 850	return 0;
 851}
 852
 853static int spi_imx_setupxfer(struct spi_device *spi,
 854				 struct spi_transfer *t)
 855{
 856	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 857	struct spi_imx_config config;
 858	int ret;
 859
 860	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
 861	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
 862	config.mode = spi->mode;
 863	config.cs = spi->chip_select;
 864
 865	if (!config.speed_hz)
 866		config.speed_hz = spi->max_speed_hz;
 867	if (!config.bpw)
 868		config.bpw = spi->bits_per_word;
 869
 870	/* Initialize the functions for transfer */
 871	if (config.bpw <= 8) {
 872		spi_imx->rx = spi_imx_buf_rx_u8;
 873		spi_imx->tx = spi_imx_buf_tx_u8;
 874	} else if (config.bpw <= 16) {
 875		spi_imx->rx = spi_imx_buf_rx_u16;
 876		spi_imx->tx = spi_imx_buf_tx_u16;
 
 
 877	} else {
 878		spi_imx->rx = spi_imx_buf_rx_u32;
 879		spi_imx->tx = spi_imx_buf_tx_u32;
 
 
 
 
 
 
 
 
 
 880	}
 881
 882	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
 883		spi_imx->usedma = 1;
 884	else
 885		spi_imx->usedma = 0;
 886
 887	if (spi_imx->usedma) {
 888		ret = spi_imx_dma_configure(spi->master,
 889					    spi_imx_bytes_per_word(config.bpw));
 890		if (ret)
 891			return ret;
 892	}
 893
 894	spi_imx->devtype_data->config(spi_imx, &config);
 895
 896	return 0;
 897}
 898
 899static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
 900{
 901	struct spi_master *master = spi_imx->bitbang.master;
 902
 903	if (master->dma_rx) {
 904		dma_release_channel(master->dma_rx);
 905		master->dma_rx = NULL;
 906	}
 907
 908	if (master->dma_tx) {
 909		dma_release_channel(master->dma_tx);
 910		master->dma_tx = NULL;
 911	}
 912}
 913
 914static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
 915			     struct spi_master *master)
 916{
 917	int ret;
 918
 919	/* use pio mode for i.mx6dl chip TKT238285 */
 920	if (of_machine_is_compatible("fsl,imx6dl"))
 921		return 0;
 922
 923	spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2;
 924
 925	/* Prepare for TX DMA: */
 926	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
 927	if (IS_ERR(master->dma_tx)) {
 928		ret = PTR_ERR(master->dma_tx);
 929		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
 930		master->dma_tx = NULL;
 931		goto err;
 932	}
 933
 934	/* Prepare for RX : */
 935	master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
 936	if (IS_ERR(master->dma_rx)) {
 937		ret = PTR_ERR(master->dma_rx);
 938		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
 939		master->dma_rx = NULL;
 940		goto err;
 941	}
 942
 943	spi_imx_dma_configure(master, 1);
 944
 945	init_completion(&spi_imx->dma_rx_completion);
 946	init_completion(&spi_imx->dma_tx_completion);
 947	master->can_dma = spi_imx_can_dma;
 948	master->max_dma_len = MAX_SDMA_BD_BYTES;
 949	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
 950					 SPI_MASTER_MUST_TX;
 951
 952	return 0;
 953err:
 954	spi_imx_sdma_exit(spi_imx);
 955	return ret;
 956}
 957
 958static void spi_imx_dma_rx_callback(void *cookie)
 959{
 960	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 961
 962	complete(&spi_imx->dma_rx_completion);
 963}
 964
 965static void spi_imx_dma_tx_callback(void *cookie)
 966{
 967	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 968
 969	complete(&spi_imx->dma_tx_completion);
 970}
 971
 972static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
 973{
 974	unsigned long timeout = 0;
 975
 976	/* Time with actual data transfer and CS change delay related to HW */
 977	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
 978
 979	/* Add extra second for scheduler related activities */
 980	timeout += 1;
 981
 982	/* Double calculated timeout */
 983	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
 984}
 985
 986static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
 987				struct spi_transfer *transfer)
 988{
 989	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
 990	unsigned long transfer_timeout;
 991	unsigned long timeout;
 992	struct spi_master *master = spi_imx->bitbang.master;
 993	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 994
 995	/*
 996	 * The TX DMA setup starts the transfer, so make sure RX is configured
 997	 * before TX.
 998	 */
 999	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1000				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1001				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1002	if (!desc_rx)
1003		return -EINVAL;
1004
1005	desc_rx->callback = spi_imx_dma_rx_callback;
1006	desc_rx->callback_param = (void *)spi_imx;
1007	dmaengine_submit(desc_rx);
1008	reinit_completion(&spi_imx->dma_rx_completion);
1009	dma_async_issue_pending(master->dma_rx);
1010
1011	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1012				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1013				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1014	if (!desc_tx) {
1015		dmaengine_terminate_all(master->dma_tx);
1016		return -EINVAL;
1017	}
1018
1019	desc_tx->callback = spi_imx_dma_tx_callback;
1020	desc_tx->callback_param = (void *)spi_imx;
1021	dmaengine_submit(desc_tx);
1022	reinit_completion(&spi_imx->dma_tx_completion);
1023	dma_async_issue_pending(master->dma_tx);
1024
1025	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1026
1027	/* Wait SDMA to finish the data transfer.*/
1028	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1029						transfer_timeout);
1030	if (!timeout) {
1031		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1032		dmaengine_terminate_all(master->dma_tx);
1033		dmaengine_terminate_all(master->dma_rx);
1034		return -ETIMEDOUT;
1035	}
1036
1037	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1038					      transfer_timeout);
1039	if (!timeout) {
1040		dev_err(&master->dev, "I/O Error in DMA RX\n");
1041		spi_imx->devtype_data->reset(spi_imx);
1042		dmaengine_terminate_all(master->dma_rx);
1043		return -ETIMEDOUT;
1044	}
1045
1046	return transfer->len;
1047}
1048
1049static int spi_imx_pio_transfer(struct spi_device *spi,
1050				struct spi_transfer *transfer)
1051{
1052	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
 
1053
1054	spi_imx->tx_buf = transfer->tx_buf;
1055	spi_imx->rx_buf = transfer->rx_buf;
1056	spi_imx->count = transfer->len;
1057	spi_imx->txfifo = 0;
 
1058
1059	reinit_completion(&spi_imx->xfer_done);
1060
1061	spi_imx_push(spi_imx);
1062
1063	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1064
1065	wait_for_completion(&spi_imx->xfer_done);
 
 
 
 
 
 
 
 
1066
1067	return transfer->len;
1068}
1069
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1070static int spi_imx_transfer(struct spi_device *spi,
1071				struct spi_transfer *transfer)
1072{
1073	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1074
 
 
 
 
 
 
 
1075	if (spi_imx->usedma)
1076		return spi_imx_dma_transfer(spi_imx, transfer);
1077	else
1078		return spi_imx_pio_transfer(spi, transfer);
1079}
1080
1081static int spi_imx_setup(struct spi_device *spi)
1082{
1083	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1084	int gpio = spi_imx->chipselect[spi->chip_select];
1085
1086	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1087		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1088
1089	if (gpio_is_valid(gpio))
1090		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
 
 
 
 
1091
1092	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1093
1094	return 0;
1095}
1096
1097static void spi_imx_cleanup(struct spi_device *spi)
1098{
1099}
1100
1101static int
1102spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1103{
1104	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1105	int ret;
1106
1107	ret = clk_enable(spi_imx->clk_per);
1108	if (ret)
1109		return ret;
1110
1111	ret = clk_enable(spi_imx->clk_ipg);
1112	if (ret) {
1113		clk_disable(spi_imx->clk_per);
1114		return ret;
1115	}
1116
1117	return 0;
 
 
 
 
 
 
1118}
1119
1120static int
1121spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1122{
1123	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1124
1125	clk_disable(spi_imx->clk_ipg);
1126	clk_disable(spi_imx->clk_per);
1127	return 0;
1128}
1129
 
 
 
 
 
 
 
 
 
 
1130static int spi_imx_probe(struct platform_device *pdev)
1131{
1132	struct device_node *np = pdev->dev.of_node;
1133	const struct of_device_id *of_id =
1134			of_match_device(spi_imx_dt_ids, &pdev->dev);
1135	struct spi_imx_master *mxc_platform_info =
1136			dev_get_platdata(&pdev->dev);
1137	struct spi_master *master;
1138	struct spi_imx_data *spi_imx;
1139	struct resource *res;
1140	int i, ret, num_cs, irq;
 
 
 
1141
1142	if (!np && !mxc_platform_info) {
1143		dev_err(&pdev->dev, "can't get the platform data\n");
1144		return -EINVAL;
1145	}
1146
1147	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
1148	if (ret < 0) {
1149		if (mxc_platform_info)
1150			num_cs = mxc_platform_info->num_chipselect;
1151		else
1152			return ret;
1153	}
1154
1155	master = spi_alloc_master(&pdev->dev,
1156			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
1157	if (!master)
1158		return -ENOMEM;
1159
 
 
 
 
 
 
1160	platform_set_drvdata(pdev, master);
1161
1162	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1163	master->bus_num = pdev->id;
1164	master->num_chipselect = num_cs;
1165
1166	spi_imx = spi_master_get_devdata(master);
1167	spi_imx->bitbang.master = master;
1168	spi_imx->dev = &pdev->dev;
 
 
 
1169
1170	spi_imx->devtype_data = of_id ? of_id->data :
1171		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
 
 
 
 
 
 
 
1172
1173	for (i = 0; i < master->num_chipselect; i++) {
1174		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
1175		if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
1176			cs_gpio = mxc_platform_info->chipselect[i];
1177
1178		spi_imx->chipselect[i] = cs_gpio;
1179		if (!gpio_is_valid(cs_gpio))
1180			continue;
1181
1182		ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
1183					DRIVER_NAME);
1184		if (ret) {
1185			dev_err(&pdev->dev, "can't get cs gpios\n");
1186			goto out_master_put;
1187		}
 
 
 
 
 
 
1188	}
1189
1190	spi_imx->bitbang.chipselect = spi_imx_chipselect;
1191	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1192	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1193	spi_imx->bitbang.master->setup = spi_imx_setup;
1194	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1195	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1196	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1197	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1198	if (is_imx51_ecspi(spi_imx))
1199		spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
 
 
 
 
 
1200
1201	init_completion(&spi_imx->xfer_done);
1202
1203	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1204	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1205	if (IS_ERR(spi_imx->base)) {
1206		ret = PTR_ERR(spi_imx->base);
1207		goto out_master_put;
1208	}
1209	spi_imx->base_phys = res->start;
1210
1211	irq = platform_get_irq(pdev, 0);
1212	if (irq < 0) {
1213		ret = irq;
1214		goto out_master_put;
1215	}
1216
1217	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1218			       dev_name(&pdev->dev), spi_imx);
1219	if (ret) {
1220		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1221		goto out_master_put;
1222	}
1223
1224	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1225	if (IS_ERR(spi_imx->clk_ipg)) {
1226		ret = PTR_ERR(spi_imx->clk_ipg);
1227		goto out_master_put;
1228	}
1229
1230	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1231	if (IS_ERR(spi_imx->clk_per)) {
1232		ret = PTR_ERR(spi_imx->clk_per);
1233		goto out_master_put;
1234	}
1235
1236	ret = clk_prepare_enable(spi_imx->clk_per);
1237	if (ret)
1238		goto out_master_put;
1239
1240	ret = clk_prepare_enable(spi_imx->clk_ipg);
1241	if (ret)
1242		goto out_put_per;
1243
1244	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1245	/*
1246	 * Only validated on i.mx6 now, can remove the constrain if validated on
1247	 * other chips.
1248	 */
1249	if (is_imx51_ecspi(spi_imx)) {
1250		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1251		if (ret == -EPROBE_DEFER)
1252			goto out_clk_put;
1253
1254		if (ret < 0)
1255			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1256				ret);
1257	}
1258
1259	spi_imx->devtype_data->reset(spi_imx);
1260
1261	spi_imx->devtype_data->intctrl(spi_imx, 0);
1262
1263	master->dev.of_node = pdev->dev.of_node;
1264	ret = spi_bitbang_start(&spi_imx->bitbang);
1265	if (ret) {
1266		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1267		goto out_clk_put;
1268	}
1269
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1270	dev_info(&pdev->dev, "probed\n");
1271
1272	clk_disable(spi_imx->clk_ipg);
1273	clk_disable(spi_imx->clk_per);
1274	return ret;
1275
 
 
1276out_clk_put:
1277	clk_disable_unprepare(spi_imx->clk_ipg);
1278out_put_per:
1279	clk_disable_unprepare(spi_imx->clk_per);
1280out_master_put:
1281	spi_master_put(master);
1282
1283	return ret;
1284}
1285
1286static int spi_imx_remove(struct platform_device *pdev)
1287{
1288	struct spi_master *master = platform_get_drvdata(pdev);
1289	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 
1290
1291	spi_bitbang_stop(&spi_imx->bitbang);
1292
 
 
 
 
 
 
 
 
 
 
1293	writel(0, spi_imx->base + MXC_CSPICTRL);
1294	clk_unprepare(spi_imx->clk_ipg);
1295	clk_unprepare(spi_imx->clk_per);
1296	spi_imx_sdma_exit(spi_imx);
1297	spi_master_put(master);
1298
1299	return 0;
1300}
1301
1302static struct platform_driver spi_imx_driver = {
1303	.driver = {
1304		   .name = DRIVER_NAME,
1305		   .of_match_table = spi_imx_dt_ids,
1306		   },
1307	.id_table = spi_imx_devtype,
1308	.probe = spi_imx_probe,
1309	.remove = spi_imx_remove,
1310};
1311module_platform_driver(spi_imx_driver);
1312
1313MODULE_DESCRIPTION("SPI Master Controller driver");
1314MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1315MODULE_LICENSE("GPL");
1316MODULE_ALIAS("platform:" DRIVER_NAME);