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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);
v4.10.11
   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};
  63
  64enum spi_imx_devtype {
  65	IMX1_CSPI,
  66	IMX21_CSPI,
  67	IMX27_CSPI,
  68	IMX31_CSPI,
  69	IMX35_CSPI,	/* CSPI on all i.mx except above */
  70	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
 
  71};
  72
  73struct spi_imx_data;
  74
  75struct spi_imx_devtype_data {
  76	void (*intctrl)(struct spi_imx_data *, int);
  77	int (*config)(struct spi_device *, struct spi_imx_config *);
 
 
  78	void (*trigger)(struct spi_imx_data *);
  79	int (*rx_available)(struct spi_imx_data *);
  80	void (*reset)(struct spi_imx_data *);
 
 
 
 
 
 
  81	enum spi_imx_devtype devtype;
  82};
  83
  84struct spi_imx_data {
  85	struct spi_bitbang bitbang;
  86	struct device *dev;
  87
  88	struct completion xfer_done;
  89	void __iomem *base;
  90	unsigned long base_phys;
  91
  92	struct clk *clk_per;
  93	struct clk *clk_ipg;
  94	unsigned long spi_clk;
  95	unsigned int spi_bus_clk;
  96
  97	unsigned int bytes_per_word;
 
  98
  99	unsigned int count;
 100	void (*tx)(struct spi_imx_data *);
 101	void (*rx)(struct spi_imx_data *);
 102	void *rx_buf;
 103	const void *tx_buf;
 104	unsigned int txfifo; /* number of words pushed in tx FIFO */
 
 
 
 
 
 
 105
 106	/* DMA */
 107	bool usedma;
 108	u32 wml;
 109	struct completion dma_rx_completion;
 110	struct completion dma_tx_completion;
 111
 112	const struct spi_imx_devtype_data *devtype_data;
 113};
 114
 115static inline int is_imx27_cspi(struct spi_imx_data *d)
 116{
 117	return d->devtype_data->devtype == IMX27_CSPI;
 118}
 119
 120static inline int is_imx35_cspi(struct spi_imx_data *d)
 121{
 122	return d->devtype_data->devtype == IMX35_CSPI;
 123}
 124
 125static inline int is_imx51_ecspi(struct spi_imx_data *d)
 126{
 127	return d->devtype_data->devtype == IMX51_ECSPI;
 128}
 129
 130static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
 131{
 132	return is_imx51_ecspi(d) ? 64 : 8;
 133}
 134
 135#define MXC_SPI_BUF_RX(type)						\
 136static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 137{									\
 138	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 139									\
 140	if (spi_imx->rx_buf) {						\
 141		*(type *)spi_imx->rx_buf = val;				\
 142		spi_imx->rx_buf += sizeof(type);			\
 143	}								\
 
 
 144}
 145
 146#define MXC_SPI_BUF_TX(type)						\
 147static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 148{									\
 149	type val = 0;							\
 150									\
 151	if (spi_imx->tx_buf) {						\
 152		val = *(type *)spi_imx->tx_buf;				\
 153		spi_imx->tx_buf += sizeof(type);			\
 154	}								\
 155									\
 156	spi_imx->count -= sizeof(type);					\
 157									\
 158	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 159}
 160
 161MXC_SPI_BUF_RX(u8)
 162MXC_SPI_BUF_TX(u8)
 163MXC_SPI_BUF_RX(u16)
 164MXC_SPI_BUF_TX(u16)
 165MXC_SPI_BUF_RX(u32)
 166MXC_SPI_BUF_TX(u32)
 167
 168/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 169 * (which is currently not the case in this driver)
 170 */
 171static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 172	256, 384, 512, 768, 1024};
 173
 174/* MX21, MX27 */
 175static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 176		unsigned int fspi, unsigned int max, unsigned int *fres)
 177{
 178	int i;
 179
 180	for (i = 2; i < max; i++)
 181		if (fspi * mxc_clkdivs[i] >= fin)
 182			break;
 183
 184	*fres = fin / mxc_clkdivs[i];
 185	return i;
 186}
 187
 188/* MX1, MX31, MX35, MX51 CSPI */
 189static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 190		unsigned int fspi, unsigned int *fres)
 191{
 192	int i, div = 4;
 193
 194	for (i = 0; i < 7; i++) {
 195		if (fspi * div >= fin)
 196			goto out;
 197		div <<= 1;
 198	}
 199
 200out:
 201	*fres = fin / div;
 202	return i;
 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 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 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 mx51_ecspi_config(struct spi_device *spi,
 338			     struct spi_imx_config *config)
 
 
 
 
 
 
 
 
 
 339{
 340	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 341	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 342	u32 clk = config->speed_hz, delay, reg;
 343	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 344
 
 
 
 
 
 
 345	/*
 346	 * The hardware seems to have a race condition when changing modes. The
 347	 * current assumption is that the selection of the channel arrives
 348	 * earlier in the hardware than the mode bits when they are written at
 349	 * the same time.
 350	 * So set master mode for all channels as we do not support slave mode.
 351	 */
 352	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 353
 354	/* set clock speed */
 355	ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk);
 356	spi_imx->spi_bus_clk = clk;
 357
 358	/* set chip select to use */
 359	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
 360
 361	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
 
 
 
 
 
 
 
 
 
 
 
 362
 363	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 
 
 
 
 
 
 
 
 364
 365	if (spi->mode & SPI_CPHA)
 366		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 367	else
 368		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 369
 370	if (spi->mode & SPI_CPOL) {
 371		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 372		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 373	} else {
 374		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 375		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 376	}
 
 377	if (spi->mode & SPI_CS_HIGH)
 378		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 379	else
 380		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 381
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 382	if (spi_imx->usedma)
 383		ctrl |= MX51_ECSPI_CTRL_SMC;
 384
 385	/* CTRL register always go first to bring out controller from reset */
 386	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 387
 388	reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 389	if (spi->mode & SPI_LOOP)
 390		reg |= MX51_ECSPI_TESTREG_LBC;
 391	else
 392		reg &= ~MX51_ECSPI_TESTREG_LBC;
 393	writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
 394
 395	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 396
 397	/*
 398	 * Wait until the changes in the configuration register CONFIGREG
 399	 * propagate into the hardware. It takes exactly one tick of the
 400	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 401	 * effect of the delay it takes for the hardware to apply changes
 402	 * is noticable if the SCLK clock run very slow. In such a case, if
 403	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 404	 * be asserted before the SCLK polarity changes, which would disrupt
 405	 * the SPI communication as the device on the other end would consider
 406	 * the change of SCLK polarity as a clock tick already.
 407	 */
 408	delay = (2 * 1000000) / clk;
 409	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
 410		udelay(delay);
 411	else			/* SCLK is _very_ slow */
 412		usleep_range(delay, delay + 10);
 413
 
 
 
 
 
 414	/*
 415	 * Configure the DMA register: setup the watermark
 416	 * and enable DMA request.
 417	 */
 418
 419	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
 420		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 421		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 422		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 423		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 424
 425	return 0;
 426}
 427
 428static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 429{
 430	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 431}
 432
 433static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 434{
 435	/* drain receive buffer */
 436	while (mx51_ecspi_rx_available(spi_imx))
 437		readl(spi_imx->base + MXC_CSPIRXDATA);
 438}
 439
 440#define MX31_INTREG_TEEN	(1 << 0)
 441#define MX31_INTREG_RREN	(1 << 3)
 442
 443#define MX31_CSPICTRL_ENABLE	(1 << 0)
 444#define MX31_CSPICTRL_MASTER	(1 << 1)
 445#define MX31_CSPICTRL_XCH	(1 << 2)
 446#define MX31_CSPICTRL_SMC	(1 << 3)
 447#define MX31_CSPICTRL_POL	(1 << 4)
 448#define MX31_CSPICTRL_PHA	(1 << 5)
 449#define MX31_CSPICTRL_SSCTL	(1 << 6)
 450#define MX31_CSPICTRL_SSPOL	(1 << 7)
 451#define MX31_CSPICTRL_BC_SHIFT	8
 452#define MX35_CSPICTRL_BL_SHIFT	20
 453#define MX31_CSPICTRL_CS_SHIFT	24
 454#define MX35_CSPICTRL_CS_SHIFT	12
 455#define MX31_CSPICTRL_DR_SHIFT	16
 456
 457#define MX31_CSPI_DMAREG	0x10
 458#define MX31_DMAREG_RH_DEN	(1<<4)
 459#define MX31_DMAREG_TH_DEN	(1<<1)
 460
 461#define MX31_CSPISTATUS		0x14
 462#define MX31_STATUS_RR		(1 << 3)
 463
 464#define MX31_CSPI_TESTREG	0x1C
 465#define MX31_TEST_LBC		(1 << 14)
 466
 467/* These functions also work for the i.MX35, but be aware that
 468 * the i.MX35 has a slightly different register layout for bits
 469 * we do not use here.
 470 */
 471static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 472{
 473	unsigned int val = 0;
 474
 475	if (enable & MXC_INT_TE)
 476		val |= MX31_INTREG_TEEN;
 477	if (enable & MXC_INT_RR)
 478		val |= MX31_INTREG_RREN;
 479
 480	writel(val, spi_imx->base + MXC_CSPIINT);
 481}
 482
 483static void mx31_trigger(struct spi_imx_data *spi_imx)
 484{
 485	unsigned int reg;
 486
 487	reg = readl(spi_imx->base + MXC_CSPICTRL);
 488	reg |= MX31_CSPICTRL_XCH;
 489	writel(reg, spi_imx->base + MXC_CSPICTRL);
 490}
 491
 492static int mx31_config(struct spi_device *spi, struct spi_imx_config *config)
 
 
 
 
 
 
 
 
 493{
 494	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 495	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 496	unsigned int clk;
 497
 498	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) <<
 499		MX31_CSPICTRL_DR_SHIFT;
 500	spi_imx->spi_bus_clk = clk;
 501
 502	if (is_imx35_cspi(spi_imx)) {
 503		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
 504		reg |= MX31_CSPICTRL_SSCTL;
 505	} else {
 506		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
 507	}
 508
 509	if (spi->mode & SPI_CPHA)
 510		reg |= MX31_CSPICTRL_PHA;
 511	if (spi->mode & SPI_CPOL)
 512		reg |= MX31_CSPICTRL_POL;
 513	if (spi->mode & SPI_CS_HIGH)
 514		reg |= MX31_CSPICTRL_SSPOL;
 515	if (spi->cs_gpio < 0)
 516		reg |= (spi->cs_gpio + 32) <<
 517			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 518						  MX31_CSPICTRL_CS_SHIFT);
 519
 520	if (spi_imx->usedma)
 521		reg |= MX31_CSPICTRL_SMC;
 522
 523	writel(reg, spi_imx->base + MXC_CSPICTRL);
 524
 525	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
 526	if (spi->mode & SPI_LOOP)
 527		reg |= MX31_TEST_LBC;
 528	else
 529		reg &= ~MX31_TEST_LBC;
 530	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 531
 532	if (spi_imx->usedma) {
 533		/* configure DMA requests when RXFIFO is half full and
 534		   when TXFIFO is half empty */
 
 
 535		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
 536			spi_imx->base + MX31_CSPI_DMAREG);
 537	}
 538
 539	return 0;
 540}
 541
 542static int mx31_rx_available(struct spi_imx_data *spi_imx)
 543{
 544	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 545}
 546
 547static void mx31_reset(struct spi_imx_data *spi_imx)
 548{
 549	/* drain receive buffer */
 550	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 551		readl(spi_imx->base + MXC_CSPIRXDATA);
 552}
 553
 554#define MX21_INTREG_RR		(1 << 4)
 555#define MX21_INTREG_TEEN	(1 << 9)
 556#define MX21_INTREG_RREN	(1 << 13)
 557
 558#define MX21_CSPICTRL_POL	(1 << 5)
 559#define MX21_CSPICTRL_PHA	(1 << 6)
 560#define MX21_CSPICTRL_SSPOL	(1 << 8)
 561#define MX21_CSPICTRL_XCH	(1 << 9)
 562#define MX21_CSPICTRL_ENABLE	(1 << 10)
 563#define MX21_CSPICTRL_MASTER	(1 << 11)
 564#define MX21_CSPICTRL_DR_SHIFT	14
 565#define MX21_CSPICTRL_CS_SHIFT	19
 566
 567static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 568{
 569	unsigned int val = 0;
 570
 571	if (enable & MXC_INT_TE)
 572		val |= MX21_INTREG_TEEN;
 573	if (enable & MXC_INT_RR)
 574		val |= MX21_INTREG_RREN;
 575
 576	writel(val, spi_imx->base + MXC_CSPIINT);
 577}
 578
 579static void mx21_trigger(struct spi_imx_data *spi_imx)
 580{
 581	unsigned int reg;
 582
 583	reg = readl(spi_imx->base + MXC_CSPICTRL);
 584	reg |= MX21_CSPICTRL_XCH;
 585	writel(reg, spi_imx->base + MXC_CSPICTRL);
 586}
 587
 588static int mx21_config(struct spi_device *spi, struct spi_imx_config *config)
 
 
 
 
 
 
 
 
 589{
 590	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 591	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 592	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 593	unsigned int clk;
 594
 595	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max, &clk)
 596		<< MX21_CSPICTRL_DR_SHIFT;
 597	spi_imx->spi_bus_clk = clk;
 598
 599	reg |= config->bpw - 1;
 600
 601	if (spi->mode & SPI_CPHA)
 602		reg |= MX21_CSPICTRL_PHA;
 603	if (spi->mode & SPI_CPOL)
 604		reg |= MX21_CSPICTRL_POL;
 605	if (spi->mode & SPI_CS_HIGH)
 606		reg |= MX21_CSPICTRL_SSPOL;
 607	if (spi->cs_gpio < 0)
 608		reg |= (spi->cs_gpio + 32) << MX21_CSPICTRL_CS_SHIFT;
 609
 610	writel(reg, spi_imx->base + MXC_CSPICTRL);
 611
 612	return 0;
 613}
 614
 615static int mx21_rx_available(struct spi_imx_data *spi_imx)
 616{
 617	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 618}
 619
 620static void mx21_reset(struct spi_imx_data *spi_imx)
 621{
 622	writel(1, spi_imx->base + MXC_RESET);
 623}
 624
 625#define MX1_INTREG_RR		(1 << 3)
 626#define MX1_INTREG_TEEN		(1 << 8)
 627#define MX1_INTREG_RREN		(1 << 11)
 628
 629#define MX1_CSPICTRL_POL	(1 << 4)
 630#define MX1_CSPICTRL_PHA	(1 << 5)
 631#define MX1_CSPICTRL_XCH	(1 << 8)
 632#define MX1_CSPICTRL_ENABLE	(1 << 9)
 633#define MX1_CSPICTRL_MASTER	(1 << 10)
 634#define MX1_CSPICTRL_DR_SHIFT	13
 635
 636static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 637{
 638	unsigned int val = 0;
 639
 640	if (enable & MXC_INT_TE)
 641		val |= MX1_INTREG_TEEN;
 642	if (enable & MXC_INT_RR)
 643		val |= MX1_INTREG_RREN;
 644
 645	writel(val, spi_imx->base + MXC_CSPIINT);
 646}
 647
 648static void mx1_trigger(struct spi_imx_data *spi_imx)
 649{
 650	unsigned int reg;
 651
 652	reg = readl(spi_imx->base + MXC_CSPICTRL);
 653	reg |= MX1_CSPICTRL_XCH;
 654	writel(reg, spi_imx->base + MXC_CSPICTRL);
 655}
 656
 657static int mx1_config(struct spi_device *spi, struct spi_imx_config *config)
 
 
 
 
 
 
 
 
 658{
 659	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 660	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 661	unsigned int clk;
 662
 663	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) <<
 664		MX1_CSPICTRL_DR_SHIFT;
 665	spi_imx->spi_bus_clk = clk;
 666
 667	reg |= config->bpw - 1;
 668
 669	if (spi->mode & SPI_CPHA)
 670		reg |= MX1_CSPICTRL_PHA;
 671	if (spi->mode & SPI_CPOL)
 672		reg |= MX1_CSPICTRL_POL;
 673
 674	writel(reg, spi_imx->base + MXC_CSPICTRL);
 675
 676	return 0;
 677}
 678
 679static int mx1_rx_available(struct spi_imx_data *spi_imx)
 680{
 681	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 682}
 683
 684static void mx1_reset(struct spi_imx_data *spi_imx)
 685{
 686	writel(1, spi_imx->base + MXC_RESET);
 687}
 688
 689static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 690	.intctrl = mx1_intctrl,
 691	.config = mx1_config,
 
 692	.trigger = mx1_trigger,
 693	.rx_available = mx1_rx_available,
 694	.reset = mx1_reset,
 
 
 
 
 695	.devtype = IMX1_CSPI,
 696};
 697
 698static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 699	.intctrl = mx21_intctrl,
 700	.config = mx21_config,
 
 701	.trigger = mx21_trigger,
 702	.rx_available = mx21_rx_available,
 703	.reset = mx21_reset,
 
 
 
 
 704	.devtype = IMX21_CSPI,
 705};
 706
 707static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 708	/* i.mx27 cspi shares the functions with i.mx21 one */
 709	.intctrl = mx21_intctrl,
 710	.config = mx21_config,
 
 711	.trigger = mx21_trigger,
 712	.rx_available = mx21_rx_available,
 713	.reset = mx21_reset,
 
 
 
 
 714	.devtype = IMX27_CSPI,
 715};
 716
 717static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 718	.intctrl = mx31_intctrl,
 719	.config = mx31_config,
 
 720	.trigger = mx31_trigger,
 721	.rx_available = mx31_rx_available,
 722	.reset = mx31_reset,
 
 
 
 
 723	.devtype = IMX31_CSPI,
 724};
 725
 726static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 727	/* i.mx35 and later cspi shares the functions with i.mx31 one */
 728	.intctrl = mx31_intctrl,
 729	.config = mx31_config,
 
 730	.trigger = mx31_trigger,
 731	.rx_available = mx31_rx_available,
 732	.reset = mx31_reset,
 
 
 
 
 733	.devtype = IMX35_CSPI,
 734};
 735
 736static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 737	.intctrl = mx51_ecspi_intctrl,
 738	.config = mx51_ecspi_config,
 
 739	.trigger = mx51_ecspi_trigger,
 740	.rx_available = mx51_ecspi_rx_available,
 741	.reset = mx51_ecspi_reset,
 
 
 
 
 
 
 742	.devtype = IMX51_ECSPI,
 743};
 744
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 745static const struct platform_device_id spi_imx_devtype[] = {
 746	{
 747		.name = "imx1-cspi",
 748		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
 749	}, {
 750		.name = "imx21-cspi",
 751		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
 752	}, {
 753		.name = "imx27-cspi",
 754		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
 755	}, {
 756		.name = "imx31-cspi",
 757		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
 758	}, {
 759		.name = "imx35-cspi",
 760		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
 761	}, {
 762		.name = "imx51-ecspi",
 763		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
 764	}, {
 
 
 
 765		/* sentinel */
 766	}
 767};
 768
 769static const struct of_device_id spi_imx_dt_ids[] = {
 770	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
 771	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
 772	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
 773	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
 774	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
 775	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
 
 776	{ /* sentinel */ }
 777};
 778MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
 779
 780static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 781{
 782	int active = is_active != BITBANG_CS_INACTIVE;
 783	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
 784
 
 
 
 785	if (!gpio_is_valid(spi->cs_gpio))
 786		return;
 787
 788	gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
 789}
 790
 
 
 
 
 
 
 
 
 
 
 791static void spi_imx_push(struct spi_imx_data *spi_imx)
 792{
 793	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 794		if (!spi_imx->count)
 795			break;
 
 
 
 
 796		spi_imx->tx(spi_imx);
 797		spi_imx->txfifo++;
 798	}
 799
 800	spi_imx->devtype_data->trigger(spi_imx);
 
 801}
 802
 803static irqreturn_t spi_imx_isr(int irq, void *dev_id)
 804{
 805	struct spi_imx_data *spi_imx = dev_id;
 806
 807	while (spi_imx->devtype_data->rx_available(spi_imx)) {
 
 808		spi_imx->rx(spi_imx);
 809		spi_imx->txfifo--;
 810	}
 811
 812	if (spi_imx->count) {
 813		spi_imx_push(spi_imx);
 814		return IRQ_HANDLED;
 815	}
 816
 817	if (spi_imx->txfifo) {
 818		/* No data left to push, but still waiting for rx data,
 819		 * enable receive data available interrupt.
 820		 */
 821		spi_imx->devtype_data->intctrl(
 822				spi_imx, MXC_INT_RR);
 823		return IRQ_HANDLED;
 824	}
 825
 826	spi_imx->devtype_data->intctrl(spi_imx, 0);
 827	complete(&spi_imx->xfer_done);
 828
 829	return IRQ_HANDLED;
 830}
 831
 832static int spi_imx_dma_configure(struct spi_master *master,
 833				 int bytes_per_word)
 834{
 835	int ret;
 836	enum dma_slave_buswidth buswidth;
 837	struct dma_slave_config rx = {}, tx = {};
 838	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 839
 840	if (bytes_per_word == spi_imx->bytes_per_word)
 841		/* Same as last time */
 842		return 0;
 843
 844	switch (bytes_per_word) {
 845	case 4:
 846		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 847		break;
 848	case 2:
 849		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
 850		break;
 851	case 1:
 852		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
 853		break;
 854	default:
 855		return -EINVAL;
 856	}
 857
 858	tx.direction = DMA_MEM_TO_DEV;
 859	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
 860	tx.dst_addr_width = buswidth;
 861	tx.dst_maxburst = spi_imx->wml;
 862	ret = dmaengine_slave_config(master->dma_tx, &tx);
 863	if (ret) {
 864		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
 865		return ret;
 866	}
 867
 868	rx.direction = DMA_DEV_TO_MEM;
 869	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
 870	rx.src_addr_width = buswidth;
 871	rx.src_maxburst = spi_imx->wml;
 872	ret = dmaengine_slave_config(master->dma_rx, &rx);
 873	if (ret) {
 874		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
 875		return ret;
 876	}
 877
 878	spi_imx->bytes_per_word = bytes_per_word;
 879
 880	return 0;
 881}
 882
 883static int spi_imx_setupxfer(struct spi_device *spi,
 884				 struct spi_transfer *t)
 885{
 886	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 887	struct spi_imx_config config;
 888	int ret;
 889
 890	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
 891	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 892
 893	if (!config.speed_hz)
 894		config.speed_hz = spi->max_speed_hz;
 895	if (!config.bpw)
 896		config.bpw = spi->bits_per_word;
 897
 898	/* Initialize the functions for transfer */
 899	if (config.bpw <= 8) {
 900		spi_imx->rx = spi_imx_buf_rx_u8;
 901		spi_imx->tx = spi_imx_buf_tx_u8;
 902	} else if (config.bpw <= 16) {
 903		spi_imx->rx = spi_imx_buf_rx_u16;
 904		spi_imx->tx = spi_imx_buf_tx_u16;
 905	} else {
 906		spi_imx->rx = spi_imx_buf_rx_u32;
 907		spi_imx->tx = spi_imx_buf_tx_u32;
 
 
 
 
 
 
 
 
 
 908	}
 909
 910	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
 911		spi_imx->usedma = 1;
 912	else
 913		spi_imx->usedma = 0;
 914
 915	if (spi_imx->usedma) {
 916		ret = spi_imx_dma_configure(spi->master,
 917					    spi_imx_bytes_per_word(config.bpw));
 918		if (ret)
 919			return ret;
 920	}
 921
 922	spi_imx->devtype_data->config(spi, &config);
 923
 924	return 0;
 925}
 926
 927static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
 928{
 929	struct spi_master *master = spi_imx->bitbang.master;
 930
 931	if (master->dma_rx) {
 932		dma_release_channel(master->dma_rx);
 933		master->dma_rx = NULL;
 934	}
 935
 936	if (master->dma_tx) {
 937		dma_release_channel(master->dma_tx);
 938		master->dma_tx = NULL;
 939	}
 940}
 941
 942static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
 943			     struct spi_master *master)
 944{
 945	int ret;
 946
 947	/* use pio mode for i.mx6dl chip TKT238285 */
 948	if (of_machine_is_compatible("fsl,imx6dl"))
 949		return 0;
 950
 951	spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2;
 952
 953	/* Prepare for TX DMA: */
 954	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
 955	if (IS_ERR(master->dma_tx)) {
 956		ret = PTR_ERR(master->dma_tx);
 957		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
 958		master->dma_tx = NULL;
 959		goto err;
 960	}
 961
 962	/* Prepare for RX : */
 963	master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
 964	if (IS_ERR(master->dma_rx)) {
 965		ret = PTR_ERR(master->dma_rx);
 966		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
 967		master->dma_rx = NULL;
 968		goto err;
 969	}
 970
 971	spi_imx_dma_configure(master, 1);
 972
 973	init_completion(&spi_imx->dma_rx_completion);
 974	init_completion(&spi_imx->dma_tx_completion);
 975	master->can_dma = spi_imx_can_dma;
 976	master->max_dma_len = MAX_SDMA_BD_BYTES;
 977	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
 978					 SPI_MASTER_MUST_TX;
 979
 980	return 0;
 981err:
 982	spi_imx_sdma_exit(spi_imx);
 983	return ret;
 984}
 985
 986static void spi_imx_dma_rx_callback(void *cookie)
 987{
 988	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 989
 990	complete(&spi_imx->dma_rx_completion);
 991}
 992
 993static void spi_imx_dma_tx_callback(void *cookie)
 994{
 995	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 996
 997	complete(&spi_imx->dma_tx_completion);
 998}
 999
1000static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1001{
1002	unsigned long timeout = 0;
1003
1004	/* Time with actual data transfer and CS change delay related to HW */
1005	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1006
1007	/* Add extra second for scheduler related activities */
1008	timeout += 1;
1009
1010	/* Double calculated timeout */
1011	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1012}
1013
1014static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1015				struct spi_transfer *transfer)
1016{
1017	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1018	unsigned long transfer_timeout;
1019	unsigned long timeout;
1020	struct spi_master *master = spi_imx->bitbang.master;
1021	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1022
1023	/*
1024	 * The TX DMA setup starts the transfer, so make sure RX is configured
1025	 * before TX.
1026	 */
1027	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1028				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1029				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1030	if (!desc_rx)
1031		return -EINVAL;
1032
1033	desc_rx->callback = spi_imx_dma_rx_callback;
1034	desc_rx->callback_param = (void *)spi_imx;
1035	dmaengine_submit(desc_rx);
1036	reinit_completion(&spi_imx->dma_rx_completion);
1037	dma_async_issue_pending(master->dma_rx);
1038
1039	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1040				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1041				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1042	if (!desc_tx) {
1043		dmaengine_terminate_all(master->dma_tx);
1044		return -EINVAL;
1045	}
1046
1047	desc_tx->callback = spi_imx_dma_tx_callback;
1048	desc_tx->callback_param = (void *)spi_imx;
1049	dmaengine_submit(desc_tx);
1050	reinit_completion(&spi_imx->dma_tx_completion);
1051	dma_async_issue_pending(master->dma_tx);
1052
1053	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1054
1055	/* Wait SDMA to finish the data transfer.*/
1056	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1057						transfer_timeout);
1058	if (!timeout) {
1059		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1060		dmaengine_terminate_all(master->dma_tx);
1061		dmaengine_terminate_all(master->dma_rx);
1062		return -ETIMEDOUT;
1063	}
1064
1065	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1066					      transfer_timeout);
1067	if (!timeout) {
1068		dev_err(&master->dev, "I/O Error in DMA RX\n");
1069		spi_imx->devtype_data->reset(spi_imx);
1070		dmaengine_terminate_all(master->dma_rx);
1071		return -ETIMEDOUT;
1072	}
1073
1074	return transfer->len;
1075}
1076
1077static int spi_imx_pio_transfer(struct spi_device *spi,
1078				struct spi_transfer *transfer)
1079{
1080	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1081	unsigned long transfer_timeout;
1082	unsigned long timeout;
1083
1084	spi_imx->tx_buf = transfer->tx_buf;
1085	spi_imx->rx_buf = transfer->rx_buf;
1086	spi_imx->count = transfer->len;
1087	spi_imx->txfifo = 0;
 
1088
1089	reinit_completion(&spi_imx->xfer_done);
1090
1091	spi_imx_push(spi_imx);
1092
1093	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1094
1095	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1096
1097	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1098					      transfer_timeout);
1099	if (!timeout) {
1100		dev_err(&spi->dev, "I/O Error in PIO\n");
1101		spi_imx->devtype_data->reset(spi_imx);
1102		return -ETIMEDOUT;
1103	}
1104
1105	return transfer->len;
1106}
1107
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1108static int spi_imx_transfer(struct spi_device *spi,
1109				struct spi_transfer *transfer)
1110{
1111	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1112
 
 
 
 
 
 
 
1113	if (spi_imx->usedma)
1114		return spi_imx_dma_transfer(spi_imx, transfer);
1115	else
1116		return spi_imx_pio_transfer(spi, transfer);
1117}
1118
1119static int spi_imx_setup(struct spi_device *spi)
1120{
1121	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1122		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1123
 
 
 
1124	if (gpio_is_valid(spi->cs_gpio))
1125		gpio_direction_output(spi->cs_gpio,
1126				      spi->mode & SPI_CS_HIGH ? 0 : 1);
1127
1128	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1129
1130	return 0;
1131}
1132
1133static void spi_imx_cleanup(struct spi_device *spi)
1134{
1135}
1136
1137static int
1138spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1139{
1140	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1141	int ret;
1142
1143	ret = clk_enable(spi_imx->clk_per);
1144	if (ret)
1145		return ret;
1146
1147	ret = clk_enable(spi_imx->clk_ipg);
1148	if (ret) {
1149		clk_disable(spi_imx->clk_per);
1150		return ret;
1151	}
1152
1153	return 0;
 
 
 
 
 
 
1154}
1155
1156static int
1157spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1158{
1159	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1160
1161	clk_disable(spi_imx->clk_ipg);
1162	clk_disable(spi_imx->clk_per);
1163	return 0;
1164}
1165
 
 
 
 
 
 
 
 
 
 
1166static int spi_imx_probe(struct platform_device *pdev)
1167{
1168	struct device_node *np = pdev->dev.of_node;
1169	const struct of_device_id *of_id =
1170			of_match_device(spi_imx_dt_ids, &pdev->dev);
1171	struct spi_imx_master *mxc_platform_info =
1172			dev_get_platdata(&pdev->dev);
1173	struct spi_master *master;
1174	struct spi_imx_data *spi_imx;
1175	struct resource *res;
1176	int i, ret, irq;
 
 
 
1177
1178	if (!np && !mxc_platform_info) {
1179		dev_err(&pdev->dev, "can't get the platform data\n");
1180		return -EINVAL;
1181	}
1182
1183	master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data));
 
 
 
 
 
 
 
1184	if (!master)
1185		return -ENOMEM;
1186
 
 
 
 
 
 
1187	platform_set_drvdata(pdev, master);
1188
1189	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1190	master->bus_num = np ? -1 : pdev->id;
1191
1192	spi_imx = spi_master_get_devdata(master);
1193	spi_imx->bitbang.master = master;
1194	spi_imx->dev = &pdev->dev;
 
1195
1196	spi_imx->devtype_data = of_id ? of_id->data :
1197		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1198
 
1199	if (mxc_platform_info) {
1200		master->num_chipselect = mxc_platform_info->num_chipselect;
1201		master->cs_gpios = devm_kzalloc(&master->dev,
1202			sizeof(int) * master->num_chipselect, GFP_KERNEL);
1203		if (!master->cs_gpios)
1204			return -ENOMEM;
1205
1206		for (i = 0; i < master->num_chipselect; i++)
1207			master->cs_gpios[i] = mxc_platform_info->chipselect[i];
1208 	}
 
 
 
 
 
 
 
 
 
1209
1210	spi_imx->bitbang.chipselect = spi_imx_chipselect;
1211	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1212	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1213	spi_imx->bitbang.master->setup = spi_imx_setup;
1214	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1215	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1216	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1217	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1218	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx))
1219		spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
 
 
 
 
 
1220
1221	init_completion(&spi_imx->xfer_done);
1222
1223	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1224	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1225	if (IS_ERR(spi_imx->base)) {
1226		ret = PTR_ERR(spi_imx->base);
1227		goto out_master_put;
1228	}
1229	spi_imx->base_phys = res->start;
1230
1231	irq = platform_get_irq(pdev, 0);
1232	if (irq < 0) {
1233		ret = irq;
1234		goto out_master_put;
1235	}
1236
1237	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1238			       dev_name(&pdev->dev), spi_imx);
1239	if (ret) {
1240		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1241		goto out_master_put;
1242	}
1243
1244	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1245	if (IS_ERR(spi_imx->clk_ipg)) {
1246		ret = PTR_ERR(spi_imx->clk_ipg);
1247		goto out_master_put;
1248	}
1249
1250	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1251	if (IS_ERR(spi_imx->clk_per)) {
1252		ret = PTR_ERR(spi_imx->clk_per);
1253		goto out_master_put;
1254	}
1255
1256	ret = clk_prepare_enable(spi_imx->clk_per);
1257	if (ret)
1258		goto out_master_put;
1259
1260	ret = clk_prepare_enable(spi_imx->clk_ipg);
1261	if (ret)
1262		goto out_put_per;
1263
1264	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1265	/*
1266	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1267	 * if validated on other chips.
1268	 */
1269	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx)) {
1270		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1271		if (ret == -EPROBE_DEFER)
1272			goto out_clk_put;
1273
1274		if (ret < 0)
1275			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1276				ret);
1277	}
1278
1279	spi_imx->devtype_data->reset(spi_imx);
1280
1281	spi_imx->devtype_data->intctrl(spi_imx, 0);
1282
1283	master->dev.of_node = pdev->dev.of_node;
1284	ret = spi_bitbang_start(&spi_imx->bitbang);
1285	if (ret) {
1286		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1287		goto out_clk_put;
1288	}
1289
1290	if (!master->cs_gpios) {
1291		dev_err(&pdev->dev, "No CS GPIOs available\n");
1292		ret = -EINVAL;
1293		goto out_clk_put;
1294	}
1295
1296	for (i = 0; i < master->num_chipselect; i++) {
1297		if (!gpio_is_valid(master->cs_gpios[i]))
1298			continue;
1299
1300		ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i],
1301					DRIVER_NAME);
1302		if (ret) {
1303			dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
1304				master->cs_gpios[i]);
1305			goto out_clk_put;
1306		}
1307	}
1308
1309	dev_info(&pdev->dev, "probed\n");
1310
1311	clk_disable(spi_imx->clk_ipg);
1312	clk_disable(spi_imx->clk_per);
1313	return ret;
1314
 
 
1315out_clk_put:
1316	clk_disable_unprepare(spi_imx->clk_ipg);
1317out_put_per:
1318	clk_disable_unprepare(spi_imx->clk_per);
1319out_master_put:
1320	spi_master_put(master);
1321
1322	return ret;
1323}
1324
1325static int spi_imx_remove(struct platform_device *pdev)
1326{
1327	struct spi_master *master = platform_get_drvdata(pdev);
1328	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 
1329
1330	spi_bitbang_stop(&spi_imx->bitbang);
1331
 
 
 
 
 
 
 
 
 
 
1332	writel(0, spi_imx->base + MXC_CSPICTRL);
1333	clk_unprepare(spi_imx->clk_ipg);
1334	clk_unprepare(spi_imx->clk_per);
1335	spi_imx_sdma_exit(spi_imx);
1336	spi_master_put(master);
1337
1338	return 0;
1339}
1340
1341static struct platform_driver spi_imx_driver = {
1342	.driver = {
1343		   .name = DRIVER_NAME,
1344		   .of_match_table = spi_imx_dt_ids,
1345		   },
1346	.id_table = spi_imx_devtype,
1347	.probe = spi_imx_probe,
1348	.remove = spi_imx_remove,
1349};
1350module_platform_driver(spi_imx_driver);
1351
1352MODULE_DESCRIPTION("SPI Master Controller driver");
1353MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1354MODULE_LICENSE("GPL");
1355MODULE_ALIAS("platform:" DRIVER_NAME);