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v5.9
   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/interrupt.h>
  12#include <linux/io.h>
  13#include <linux/irq.h>
  14#include <linux/kernel.h>
  15#include <linux/module.h>
  16#include <linux/pinctrl/consumer.h>
  17#include <linux/platform_device.h>
  18#include <linux/pm_runtime.h>
  19#include <linux/slab.h>
  20#include <linux/spi/spi.h>
  21#include <linux/spi/spi_bitbang.h>
  22#include <linux/types.h>
  23#include <linux/of.h>
  24#include <linux/of_device.h>
  25#include <linux/property.h>
  26
  27#include <linux/platform_data/dma-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_RPM_TIMEOUT		2000 /* 2000ms */
  36
  37#define MXC_CSPIRXDATA		0x00
  38#define MXC_CSPITXDATA		0x04
  39#define MXC_CSPICTRL		0x08
  40#define MXC_CSPIINT		0x0c
  41#define MXC_RESET		0x1c
  42
  43/* generic defines to abstract from the different register layouts */
  44#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
  45#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
  46#define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
  47
  48/* The maximum bytes that a sdma BD can transfer. */
  49#define MAX_SDMA_BD_BYTES (1 << 15)
  50#define MX51_ECSPI_CTRL_MAX_BURST	512
  51/* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
  52#define MX53_MAX_TRANSFER_BYTES		512
 
  53
  54enum spi_imx_devtype {
  55	IMX1_CSPI,
  56	IMX21_CSPI,
  57	IMX27_CSPI,
  58	IMX31_CSPI,
  59	IMX35_CSPI,	/* CSPI on all i.mx except above */
  60	IMX51_ECSPI,	/* ECSPI on i.mx51 */
  61	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
  62};
  63
  64struct spi_imx_data;
  65
  66struct spi_imx_devtype_data {
  67	void (*intctrl)(struct spi_imx_data *, int);
  68	int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
  69	int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *,
  70				struct spi_transfer *);
  71	void (*trigger)(struct spi_imx_data *);
  72	int (*rx_available)(struct spi_imx_data *);
  73	void (*reset)(struct spi_imx_data *);
  74	void (*setup_wml)(struct spi_imx_data *);
  75	void (*disable)(struct spi_imx_data *);
  76	void (*disable_dma)(struct spi_imx_data *);
  77	bool has_dmamode;
  78	bool has_slavemode;
  79	unsigned int fifo_size;
  80	bool dynamic_burst;
  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 bits_per_word;
  98	unsigned int spi_drctl;
  99
 100	unsigned int count, remainder;
 101	void (*tx)(struct spi_imx_data *);
 102	void (*rx)(struct spi_imx_data *);
 103	void *rx_buf;
 104	const void *tx_buf;
 105	unsigned int txfifo; /* number of words pushed in tx FIFO */
 106	unsigned int dynamic_burst;
 107
 108	/* Slave mode */
 109	bool slave_mode;
 110	bool slave_aborted;
 111	unsigned int slave_burst;
 112
 113	/* DMA */
 114	bool usedma;
 115	u32 wml;
 116	struct completion dma_rx_completion;
 117	struct completion dma_tx_completion;
 118
 119	const struct spi_imx_devtype_data *devtype_data;
 120};
 121
 122static inline int is_imx27_cspi(struct spi_imx_data *d)
 123{
 124	return d->devtype_data->devtype == IMX27_CSPI;
 125}
 126
 127static inline int is_imx35_cspi(struct spi_imx_data *d)
 128{
 129	return d->devtype_data->devtype == IMX35_CSPI;
 130}
 131
 132static inline int is_imx51_ecspi(struct spi_imx_data *d)
 133{
 134	return d->devtype_data->devtype == IMX51_ECSPI;
 135}
 136
 137static inline int is_imx53_ecspi(struct spi_imx_data *d)
 138{
 139	return d->devtype_data->devtype == IMX53_ECSPI;
 140}
 141
 142#define MXC_SPI_BUF_RX(type)						\
 143static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 144{									\
 145	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 146									\
 147	if (spi_imx->rx_buf) {						\
 148		*(type *)spi_imx->rx_buf = val;				\
 149		spi_imx->rx_buf += sizeof(type);			\
 150	}								\
 151									\
 152	spi_imx->remainder -= sizeof(type);				\
 153}
 154
 155#define MXC_SPI_BUF_TX(type)						\
 156static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 157{									\
 158	type val = 0;							\
 159									\
 160	if (spi_imx->tx_buf) {						\
 161		val = *(type *)spi_imx->tx_buf;				\
 162		spi_imx->tx_buf += sizeof(type);			\
 163	}								\
 164									\
 165	spi_imx->count -= sizeof(type);					\
 166									\
 167	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 168}
 169
 170MXC_SPI_BUF_RX(u8)
 171MXC_SPI_BUF_TX(u8)
 172MXC_SPI_BUF_RX(u16)
 173MXC_SPI_BUF_TX(u16)
 174MXC_SPI_BUF_RX(u32)
 175MXC_SPI_BUF_TX(u32)
 176
 177/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 178 * (which is currently not the case in this driver)
 179 */
 180static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 181	256, 384, 512, 768, 1024};
 182
 183/* MX21, MX27 */
 184static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 185		unsigned int fspi, unsigned int max, unsigned int *fres)
 186{
 187	int i;
 188
 189	for (i = 2; i < max; i++)
 190		if (fspi * mxc_clkdivs[i] >= fin)
 191			break;
 192
 193	*fres = fin / mxc_clkdivs[i];
 194	return i;
 195}
 196
 197/* MX1, MX31, MX35, MX51 CSPI */
 198static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 199		unsigned int fspi, unsigned int *fres)
 200{
 201	int i, div = 4;
 202
 203	for (i = 0; i < 7; i++) {
 204		if (fspi * div >= fin)
 205			goto out;
 206		div <<= 1;
 207	}
 208
 209out:
 210	*fres = fin / div;
 211	return i;
 212}
 213
 214static int spi_imx_bytes_per_word(const int bits_per_word)
 215{
 216	if (bits_per_word <= 8)
 217		return 1;
 218	else if (bits_per_word <= 16)
 219		return 2;
 220	else
 221		return 4;
 222}
 223
 224static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 225			 struct spi_transfer *transfer)
 226{
 227	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 228
 229	if (!use_dma || master->fallback)
 230		return false;
 231
 232	if (!master->dma_rx)
 233		return false;
 234
 235	if (spi_imx->slave_mode)
 236		return false;
 237
 238	if (transfer->len < spi_imx->devtype_data->fifo_size)
 239		return false;
 240
 241	spi_imx->dynamic_burst = 0;
 242
 243	return true;
 244}
 245
 246#define MX51_ECSPI_CTRL		0x08
 247#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
 248#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 249#define MX51_ECSPI_CTRL_SMC		(1 << 3)
 250#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 251#define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
 252#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
 253#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 254#define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
 255#define MX51_ECSPI_CTRL_BL_OFFSET	20
 256#define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
 257
 258#define MX51_ECSPI_CONFIG	0x0c
 259#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
 260#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
 261#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
 262#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
 263#define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
 264
 265#define MX51_ECSPI_INT		0x10
 266#define MX51_ECSPI_INT_TEEN		(1 <<  0)
 267#define MX51_ECSPI_INT_RREN		(1 <<  3)
 268#define MX51_ECSPI_INT_RDREN		(1 <<  4)
 269
 270#define MX51_ECSPI_DMA		0x14
 271#define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
 272#define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
 273#define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
 274
 275#define MX51_ECSPI_DMA_TEDEN		(1 << 7)
 276#define MX51_ECSPI_DMA_RXDEN		(1 << 23)
 277#define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
 278
 279#define MX51_ECSPI_STAT		0x18
 280#define MX51_ECSPI_STAT_RR		(1 <<  3)
 281
 282#define MX51_ECSPI_TESTREG	0x20
 283#define MX51_ECSPI_TESTREG_LBC	BIT(31)
 284
 285static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
 286{
 287	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
 288#ifdef __LITTLE_ENDIAN
 289	unsigned int bytes_per_word;
 290#endif
 291
 292	if (spi_imx->rx_buf) {
 293#ifdef __LITTLE_ENDIAN
 294		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 295		if (bytes_per_word == 1)
 296			val = cpu_to_be32(val);
 297		else if (bytes_per_word == 2)
 298			val = (val << 16) | (val >> 16);
 299#endif
 300		*(u32 *)spi_imx->rx_buf = val;
 301		spi_imx->rx_buf += sizeof(u32);
 302	}
 303
 304	spi_imx->remainder -= sizeof(u32);
 305}
 306
 307static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
 308{
 309	int unaligned;
 310	u32 val;
 311
 312	unaligned = spi_imx->remainder % 4;
 313
 314	if (!unaligned) {
 315		spi_imx_buf_rx_swap_u32(spi_imx);
 316		return;
 317	}
 318
 319	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 320		spi_imx_buf_rx_u16(spi_imx);
 321		return;
 322	}
 323
 324	val = readl(spi_imx->base + MXC_CSPIRXDATA);
 325
 326	while (unaligned--) {
 327		if (spi_imx->rx_buf) {
 328			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
 329			spi_imx->rx_buf++;
 330		}
 331		spi_imx->remainder--;
 332	}
 333}
 334
 335static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
 336{
 337	u32 val = 0;
 338#ifdef __LITTLE_ENDIAN
 339	unsigned int bytes_per_word;
 340#endif
 341
 342	if (spi_imx->tx_buf) {
 343		val = *(u32 *)spi_imx->tx_buf;
 344		spi_imx->tx_buf += sizeof(u32);
 345	}
 346
 347	spi_imx->count -= sizeof(u32);
 348#ifdef __LITTLE_ENDIAN
 349	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 350
 351	if (bytes_per_word == 1)
 352		val = cpu_to_be32(val);
 353	else if (bytes_per_word == 2)
 354		val = (val << 16) | (val >> 16);
 355#endif
 356	writel(val, spi_imx->base + MXC_CSPITXDATA);
 357}
 358
 359static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
 360{
 361	int unaligned;
 362	u32 val = 0;
 363
 364	unaligned = spi_imx->count % 4;
 365
 366	if (!unaligned) {
 367		spi_imx_buf_tx_swap_u32(spi_imx);
 368		return;
 369	}
 370
 371	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 372		spi_imx_buf_tx_u16(spi_imx);
 373		return;
 374	}
 375
 376	while (unaligned--) {
 377		if (spi_imx->tx_buf) {
 378			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
 379			spi_imx->tx_buf++;
 380		}
 381		spi_imx->count--;
 382	}
 383
 384	writel(val, spi_imx->base + MXC_CSPITXDATA);
 385}
 386
 387static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
 388{
 389	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
 390
 391	if (spi_imx->rx_buf) {
 392		int n_bytes = spi_imx->slave_burst % sizeof(val);
 393
 394		if (!n_bytes)
 395			n_bytes = sizeof(val);
 396
 397		memcpy(spi_imx->rx_buf,
 398		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
 399
 400		spi_imx->rx_buf += n_bytes;
 401		spi_imx->slave_burst -= n_bytes;
 402	}
 403
 404	spi_imx->remainder -= sizeof(u32);
 405}
 406
 407static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
 408{
 409	u32 val = 0;
 410	int n_bytes = spi_imx->count % sizeof(val);
 411
 412	if (!n_bytes)
 413		n_bytes = sizeof(val);
 414
 415	if (spi_imx->tx_buf) {
 416		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
 417		       spi_imx->tx_buf, n_bytes);
 418		val = cpu_to_be32(val);
 419		spi_imx->tx_buf += n_bytes;
 420	}
 421
 422	spi_imx->count -= n_bytes;
 423
 424	writel(val, spi_imx->base + MXC_CSPITXDATA);
 425}
 426
 427/* MX51 eCSPI */
 428static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 429				      unsigned int fspi, unsigned int *fres)
 430{
 431	/*
 432	 * there are two 4-bit dividers, the pre-divider divides by
 433	 * $pre, the post-divider by 2^$post
 434	 */
 435	unsigned int pre, post;
 436	unsigned int fin = spi_imx->spi_clk;
 437
 438	if (unlikely(fspi > fin))
 439		return 0;
 440
 441	post = fls(fin) - fls(fspi);
 442	if (fin > fspi << post)
 443		post++;
 444
 445	/* now we have: (fin <= fspi << post) with post being minimal */
 446
 447	post = max(4U, post) - 4;
 448	if (unlikely(post > 0xf)) {
 449		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 450				fspi, fin);
 451		return 0xff;
 452	}
 453
 454	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 455
 456	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 457			__func__, fin, fspi, post, pre);
 458
 459	/* Resulting frequency for the SCLK line. */
 460	*fres = (fin / (pre + 1)) >> post;
 461
 462	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 463		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 464}
 465
 466static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 467{
 468	unsigned val = 0;
 469
 470	if (enable & MXC_INT_TE)
 471		val |= MX51_ECSPI_INT_TEEN;
 472
 473	if (enable & MXC_INT_RR)
 474		val |= MX51_ECSPI_INT_RREN;
 475
 476	if (enable & MXC_INT_RDR)
 477		val |= MX51_ECSPI_INT_RDREN;
 478
 479	writel(val, spi_imx->base + MX51_ECSPI_INT);
 480}
 481
 482static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 483{
 484	u32 reg;
 485
 486	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 487	reg |= MX51_ECSPI_CTRL_XCH;
 488	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 489}
 490
 491static void mx51_disable_dma(struct spi_imx_data *spi_imx)
 492{
 493	writel(0, spi_imx->base + MX51_ECSPI_DMA);
 494}
 495
 496static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
 497{
 498	u32 ctrl;
 499
 500	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 501	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
 502	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 503}
 504
 505static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
 506				      struct spi_message *msg)
 507{
 508	struct spi_device *spi = msg->spi;
 509	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 510	u32 testreg;
 511	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 512
 513	/* set Master or Slave mode */
 514	if (spi_imx->slave_mode)
 515		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
 516	else
 517		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 518
 519	/*
 520	 * Enable SPI_RDY handling (falling edge/level triggered).
 
 
 
 
 521	 */
 522	if (spi->mode & SPI_READY)
 523		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
 524
 525	/* set chip select to use */
 526	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
 527
 528	/*
 529	 * The ctrl register must be written first, with the EN bit set other
 530	 * registers must not be written to.
 531	 */
 532	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 533
 534	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 535	if (spi->mode & SPI_LOOP)
 536		testreg |= MX51_ECSPI_TESTREG_LBC;
 537	else
 538		testreg &= ~MX51_ECSPI_TESTREG_LBC;
 539	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
 540
 541	/*
 542	 * eCSPI burst completion by Chip Select signal in Slave mode
 543	 * is not functional for imx53 Soc, config SPI burst completed when
 544	 * BURST_LENGTH + 1 bits are received
 545	 */
 546	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 547		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 548	else
 549		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 550
 551	if (spi->mode & SPI_CPHA)
 552		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 553	else
 554		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 555
 556	if (spi->mode & SPI_CPOL) {
 557		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 558		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 559	} else {
 560		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 561		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 562	}
 563
 564	if (spi->mode & SPI_CS_HIGH)
 565		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 566	else
 567		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 568
 569	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 570
 571	return 0;
 572}
 573
 574static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
 575				       struct spi_device *spi,
 576				       struct spi_transfer *t)
 577{
 578	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 579	u32 clk = t->speed_hz, delay;
 580
 581	/* Clear BL field and set the right value */
 582	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
 583	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 584		ctrl |= (spi_imx->slave_burst * 8 - 1)
 585			<< MX51_ECSPI_CTRL_BL_OFFSET;
 586	else
 587		ctrl |= (spi_imx->bits_per_word - 1)
 588			<< MX51_ECSPI_CTRL_BL_OFFSET;
 589
 590	/* set clock speed */
 591	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
 592		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
 593	ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk);
 594	spi_imx->spi_bus_clk = clk;
 595
 596	if (spi_imx->usedma)
 597		ctrl |= MX51_ECSPI_CTRL_SMC;
 598
 599	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 600
 601	/*
 602	 * Wait until the changes in the configuration register CONFIGREG
 603	 * propagate into the hardware. It takes exactly one tick of the
 604	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 605	 * effect of the delay it takes for the hardware to apply changes
 606	 * is noticable if the SCLK clock run very slow. In such a case, if
 607	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 608	 * be asserted before the SCLK polarity changes, which would disrupt
 609	 * the SPI communication as the device on the other end would consider
 610	 * the change of SCLK polarity as a clock tick already.
 611	 */
 612	delay = (2 * 1000000) / clk;
 613	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
 614		udelay(delay);
 615	else			/* SCLK is _very_ slow */
 616		usleep_range(delay, delay + 10);
 617
 618	return 0;
 619}
 620
 621static void mx51_setup_wml(struct spi_imx_data *spi_imx)
 622{
 623	/*
 624	 * Configure the DMA register: setup the watermark
 625	 * and enable DMA request.
 626	 */
 627	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
 628		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 629		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 630		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 631		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 632}
 633
 634static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 635{
 636	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 637}
 638
 639static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 640{
 641	/* drain receive buffer */
 642	while (mx51_ecspi_rx_available(spi_imx))
 643		readl(spi_imx->base + MXC_CSPIRXDATA);
 644}
 645
 646#define MX31_INTREG_TEEN	(1 << 0)
 647#define MX31_INTREG_RREN	(1 << 3)
 648
 649#define MX31_CSPICTRL_ENABLE	(1 << 0)
 650#define MX31_CSPICTRL_MASTER	(1 << 1)
 651#define MX31_CSPICTRL_XCH	(1 << 2)
 652#define MX31_CSPICTRL_SMC	(1 << 3)
 653#define MX31_CSPICTRL_POL	(1 << 4)
 654#define MX31_CSPICTRL_PHA	(1 << 5)
 655#define MX31_CSPICTRL_SSCTL	(1 << 6)
 656#define MX31_CSPICTRL_SSPOL	(1 << 7)
 657#define MX31_CSPICTRL_BC_SHIFT	8
 658#define MX35_CSPICTRL_BL_SHIFT	20
 659#define MX31_CSPICTRL_CS_SHIFT	24
 660#define MX35_CSPICTRL_CS_SHIFT	12
 661#define MX31_CSPICTRL_DR_SHIFT	16
 662
 663#define MX31_CSPI_DMAREG	0x10
 664#define MX31_DMAREG_RH_DEN	(1<<4)
 665#define MX31_DMAREG_TH_DEN	(1<<1)
 666
 667#define MX31_CSPISTATUS		0x14
 668#define MX31_STATUS_RR		(1 << 3)
 669
 670#define MX31_CSPI_TESTREG	0x1C
 671#define MX31_TEST_LBC		(1 << 14)
 672
 673/* These functions also work for the i.MX35, but be aware that
 674 * the i.MX35 has a slightly different register layout for bits
 675 * we do not use here.
 676 */
 677static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 678{
 679	unsigned int val = 0;
 680
 681	if (enable & MXC_INT_TE)
 682		val |= MX31_INTREG_TEEN;
 683	if (enable & MXC_INT_RR)
 684		val |= MX31_INTREG_RREN;
 685
 686	writel(val, spi_imx->base + MXC_CSPIINT);
 687}
 688
 689static void mx31_trigger(struct spi_imx_data *spi_imx)
 690{
 691	unsigned int reg;
 692
 693	reg = readl(spi_imx->base + MXC_CSPICTRL);
 694	reg |= MX31_CSPICTRL_XCH;
 695	writel(reg, spi_imx->base + MXC_CSPICTRL);
 696}
 697
 698static int mx31_prepare_message(struct spi_imx_data *spi_imx,
 699				struct spi_message *msg)
 700{
 701	return 0;
 702}
 703
 704static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
 705				 struct spi_device *spi,
 706				 struct spi_transfer *t)
 707{
 708	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 709	unsigned int clk;
 710
 711	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
 712		MX31_CSPICTRL_DR_SHIFT;
 713	spi_imx->spi_bus_clk = clk;
 714
 715	if (is_imx35_cspi(spi_imx)) {
 716		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
 717		reg |= MX31_CSPICTRL_SSCTL;
 718	} else {
 719		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
 720	}
 721
 722	if (spi->mode & SPI_CPHA)
 723		reg |= MX31_CSPICTRL_PHA;
 724	if (spi->mode & SPI_CPOL)
 725		reg |= MX31_CSPICTRL_POL;
 726	if (spi->mode & SPI_CS_HIGH)
 727		reg |= MX31_CSPICTRL_SSPOL;
 728	if (!spi->cs_gpiod)
 729		reg |= (spi->chip_select) <<
 730			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 731						  MX31_CSPICTRL_CS_SHIFT);
 732
 733	if (spi_imx->usedma)
 734		reg |= MX31_CSPICTRL_SMC;
 735
 736	writel(reg, spi_imx->base + MXC_CSPICTRL);
 737
 738	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
 739	if (spi->mode & SPI_LOOP)
 740		reg |= MX31_TEST_LBC;
 741	else
 742		reg &= ~MX31_TEST_LBC;
 743	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 744
 745	if (spi_imx->usedma) {
 746		/*
 747		 * configure DMA requests when RXFIFO is half full and
 748		 * when TXFIFO is half empty
 749		 */
 750		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
 751			spi_imx->base + MX31_CSPI_DMAREG);
 752	}
 753
 754	return 0;
 755}
 756
 757static int mx31_rx_available(struct spi_imx_data *spi_imx)
 758{
 759	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 760}
 761
 762static void mx31_reset(struct spi_imx_data *spi_imx)
 763{
 764	/* drain receive buffer */
 765	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 766		readl(spi_imx->base + MXC_CSPIRXDATA);
 767}
 768
 769#define MX21_INTREG_RR		(1 << 4)
 770#define MX21_INTREG_TEEN	(1 << 9)
 771#define MX21_INTREG_RREN	(1 << 13)
 772
 773#define MX21_CSPICTRL_POL	(1 << 5)
 774#define MX21_CSPICTRL_PHA	(1 << 6)
 775#define MX21_CSPICTRL_SSPOL	(1 << 8)
 776#define MX21_CSPICTRL_XCH	(1 << 9)
 777#define MX21_CSPICTRL_ENABLE	(1 << 10)
 778#define MX21_CSPICTRL_MASTER	(1 << 11)
 779#define MX21_CSPICTRL_DR_SHIFT	14
 780#define MX21_CSPICTRL_CS_SHIFT	19
 781
 782static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 783{
 784	unsigned int val = 0;
 785
 786	if (enable & MXC_INT_TE)
 787		val |= MX21_INTREG_TEEN;
 788	if (enable & MXC_INT_RR)
 789		val |= MX21_INTREG_RREN;
 790
 791	writel(val, spi_imx->base + MXC_CSPIINT);
 792}
 793
 794static void mx21_trigger(struct spi_imx_data *spi_imx)
 795{
 796	unsigned int reg;
 797
 798	reg = readl(spi_imx->base + MXC_CSPICTRL);
 799	reg |= MX21_CSPICTRL_XCH;
 800	writel(reg, spi_imx->base + MXC_CSPICTRL);
 801}
 802
 803static int mx21_prepare_message(struct spi_imx_data *spi_imx,
 804				struct spi_message *msg)
 805{
 806	return 0;
 807}
 808
 809static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
 810				 struct spi_device *spi,
 811				 struct spi_transfer *t)
 812{
 813	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 
 814	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 815	unsigned int clk;
 816
 817	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, t->speed_hz, max, &clk)
 818		<< MX21_CSPICTRL_DR_SHIFT;
 819	spi_imx->spi_bus_clk = clk;
 820
 821	reg |= spi_imx->bits_per_word - 1;
 822
 823	if (spi->mode & SPI_CPHA)
 824		reg |= MX21_CSPICTRL_PHA;
 825	if (spi->mode & SPI_CPOL)
 826		reg |= MX21_CSPICTRL_POL;
 827	if (spi->mode & SPI_CS_HIGH)
 828		reg |= MX21_CSPICTRL_SSPOL;
 829	if (!spi->cs_gpiod)
 830		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
 831
 832	writel(reg, spi_imx->base + MXC_CSPICTRL);
 833
 834	return 0;
 835}
 836
 837static int mx21_rx_available(struct spi_imx_data *spi_imx)
 838{
 839	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 840}
 841
 842static void mx21_reset(struct spi_imx_data *spi_imx)
 843{
 844	writel(1, spi_imx->base + MXC_RESET);
 845}
 846
 847#define MX1_INTREG_RR		(1 << 3)
 848#define MX1_INTREG_TEEN		(1 << 8)
 849#define MX1_INTREG_RREN		(1 << 11)
 850
 851#define MX1_CSPICTRL_POL	(1 << 4)
 852#define MX1_CSPICTRL_PHA	(1 << 5)
 853#define MX1_CSPICTRL_XCH	(1 << 8)
 854#define MX1_CSPICTRL_ENABLE	(1 << 9)
 855#define MX1_CSPICTRL_MASTER	(1 << 10)
 856#define MX1_CSPICTRL_DR_SHIFT	13
 857
 858static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 859{
 860	unsigned int val = 0;
 861
 862	if (enable & MXC_INT_TE)
 863		val |= MX1_INTREG_TEEN;
 864	if (enable & MXC_INT_RR)
 865		val |= MX1_INTREG_RREN;
 866
 867	writel(val, spi_imx->base + MXC_CSPIINT);
 868}
 869
 870static void mx1_trigger(struct spi_imx_data *spi_imx)
 871{
 872	unsigned int reg;
 873
 874	reg = readl(spi_imx->base + MXC_CSPICTRL);
 875	reg |= MX1_CSPICTRL_XCH;
 876	writel(reg, spi_imx->base + MXC_CSPICTRL);
 877}
 878
 879static int mx1_prepare_message(struct spi_imx_data *spi_imx,
 880			       struct spi_message *msg)
 881{
 882	return 0;
 883}
 884
 885static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
 886				struct spi_device *spi,
 887				struct spi_transfer *t)
 888{
 889	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 890	unsigned int clk;
 891
 892	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
 893		MX1_CSPICTRL_DR_SHIFT;
 894	spi_imx->spi_bus_clk = clk;
 895
 896	reg |= spi_imx->bits_per_word - 1;
 897
 898	if (spi->mode & SPI_CPHA)
 899		reg |= MX1_CSPICTRL_PHA;
 900	if (spi->mode & SPI_CPOL)
 901		reg |= MX1_CSPICTRL_POL;
 902
 903	writel(reg, spi_imx->base + MXC_CSPICTRL);
 904
 905	return 0;
 906}
 907
 908static int mx1_rx_available(struct spi_imx_data *spi_imx)
 909{
 910	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 911}
 912
 913static void mx1_reset(struct spi_imx_data *spi_imx)
 914{
 915	writel(1, spi_imx->base + MXC_RESET);
 916}
 917
 918static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 919	.intctrl = mx1_intctrl,
 920	.prepare_message = mx1_prepare_message,
 921	.prepare_transfer = mx1_prepare_transfer,
 922	.trigger = mx1_trigger,
 923	.rx_available = mx1_rx_available,
 924	.reset = mx1_reset,
 925	.fifo_size = 8,
 926	.has_dmamode = false,
 927	.dynamic_burst = false,
 928	.has_slavemode = false,
 929	.devtype = IMX1_CSPI,
 930};
 931
 932static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 933	.intctrl = mx21_intctrl,
 934	.prepare_message = mx21_prepare_message,
 935	.prepare_transfer = mx21_prepare_transfer,
 936	.trigger = mx21_trigger,
 937	.rx_available = mx21_rx_available,
 938	.reset = mx21_reset,
 939	.fifo_size = 8,
 940	.has_dmamode = false,
 941	.dynamic_burst = false,
 942	.has_slavemode = false,
 943	.devtype = IMX21_CSPI,
 944};
 945
 946static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 947	/* i.mx27 cspi shares the functions with i.mx21 one */
 948	.intctrl = mx21_intctrl,
 949	.prepare_message = mx21_prepare_message,
 950	.prepare_transfer = mx21_prepare_transfer,
 951	.trigger = mx21_trigger,
 952	.rx_available = mx21_rx_available,
 953	.reset = mx21_reset,
 954	.fifo_size = 8,
 955	.has_dmamode = false,
 956	.dynamic_burst = false,
 957	.has_slavemode = false,
 958	.devtype = IMX27_CSPI,
 959};
 960
 961static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 962	.intctrl = mx31_intctrl,
 963	.prepare_message = mx31_prepare_message,
 964	.prepare_transfer = mx31_prepare_transfer,
 965	.trigger = mx31_trigger,
 966	.rx_available = mx31_rx_available,
 967	.reset = mx31_reset,
 968	.fifo_size = 8,
 969	.has_dmamode = false,
 970	.dynamic_burst = false,
 971	.has_slavemode = false,
 972	.devtype = IMX31_CSPI,
 973};
 974
 975static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 976	/* i.mx35 and later cspi shares the functions with i.mx31 one */
 977	.intctrl = mx31_intctrl,
 978	.prepare_message = mx31_prepare_message,
 979	.prepare_transfer = mx31_prepare_transfer,
 980	.trigger = mx31_trigger,
 981	.rx_available = mx31_rx_available,
 982	.reset = mx31_reset,
 983	.fifo_size = 8,
 984	.has_dmamode = true,
 985	.dynamic_burst = false,
 986	.has_slavemode = false,
 987	.devtype = IMX35_CSPI,
 988};
 989
 990static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 991	.intctrl = mx51_ecspi_intctrl,
 992	.prepare_message = mx51_ecspi_prepare_message,
 993	.prepare_transfer = mx51_ecspi_prepare_transfer,
 994	.trigger = mx51_ecspi_trigger,
 995	.rx_available = mx51_ecspi_rx_available,
 996	.reset = mx51_ecspi_reset,
 997	.setup_wml = mx51_setup_wml,
 998	.disable_dma = mx51_disable_dma,
 999	.fifo_size = 64,
1000	.has_dmamode = true,
1001	.dynamic_burst = true,
1002	.has_slavemode = true,
1003	.disable = mx51_ecspi_disable,
1004	.devtype = IMX51_ECSPI,
1005};
1006
1007static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1008	.intctrl = mx51_ecspi_intctrl,
1009	.prepare_message = mx51_ecspi_prepare_message,
1010	.prepare_transfer = mx51_ecspi_prepare_transfer,
1011	.trigger = mx51_ecspi_trigger,
1012	.rx_available = mx51_ecspi_rx_available,
1013	.disable_dma = mx51_disable_dma,
1014	.reset = mx51_ecspi_reset,
1015	.fifo_size = 64,
1016	.has_dmamode = true,
1017	.has_slavemode = true,
1018	.disable = mx51_ecspi_disable,
1019	.devtype = IMX53_ECSPI,
1020};
1021
1022static const struct platform_device_id spi_imx_devtype[] = {
1023	{
1024		.name = "imx1-cspi",
1025		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
1026	}, {
1027		.name = "imx21-cspi",
1028		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
1029	}, {
1030		.name = "imx27-cspi",
1031		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
1032	}, {
1033		.name = "imx31-cspi",
1034		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
1035	}, {
1036		.name = "imx35-cspi",
1037		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
1038	}, {
1039		.name = "imx51-ecspi",
1040		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
1041	}, {
1042		.name = "imx53-ecspi",
1043		.driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
1044	}, {
1045		/* sentinel */
1046	}
1047};
1048
1049static const struct of_device_id spi_imx_dt_ids[] = {
1050	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1051	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1052	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1053	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1054	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1055	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1056	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1057	{ /* sentinel */ }
1058};
1059MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1060
1061static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1062{
1063	u32 ctrl;
 
 
 
1064
1065	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1066	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1067	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1068	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1069}
1070
1071static void spi_imx_push(struct spi_imx_data *spi_imx)
1072{
1073	unsigned int burst_len, fifo_words;
1074
1075	if (spi_imx->dynamic_burst)
1076		fifo_words = 4;
1077	else
1078		fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1079	/*
1080	 * Reload the FIFO when the remaining bytes to be transferred in the
1081	 * current burst is 0. This only applies when bits_per_word is a
1082	 * multiple of 8.
1083	 */
1084	if (!spi_imx->remainder) {
1085		if (spi_imx->dynamic_burst) {
1086
1087			/* We need to deal unaligned data first */
1088			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1089
1090			if (!burst_len)
1091				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1092
1093			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1094
1095			spi_imx->remainder = burst_len;
1096		} else {
1097			spi_imx->remainder = fifo_words;
1098		}
1099	}
1100
1101	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1102		if (!spi_imx->count)
1103			break;
1104		if (spi_imx->dynamic_burst &&
1105		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1106						     fifo_words))
1107			break;
1108		spi_imx->tx(spi_imx);
1109		spi_imx->txfifo++;
1110	}
1111
1112	if (!spi_imx->slave_mode)
1113		spi_imx->devtype_data->trigger(spi_imx);
1114}
1115
1116static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1117{
1118	struct spi_imx_data *spi_imx = dev_id;
1119
1120	while (spi_imx->txfifo &&
1121	       spi_imx->devtype_data->rx_available(spi_imx)) {
1122		spi_imx->rx(spi_imx);
1123		spi_imx->txfifo--;
1124	}
1125
1126	if (spi_imx->count) {
1127		spi_imx_push(spi_imx);
1128		return IRQ_HANDLED;
1129	}
1130
1131	if (spi_imx->txfifo) {
1132		/* No data left to push, but still waiting for rx data,
1133		 * enable receive data available interrupt.
1134		 */
1135		spi_imx->devtype_data->intctrl(
1136				spi_imx, MXC_INT_RR);
1137		return IRQ_HANDLED;
1138	}
1139
1140	spi_imx->devtype_data->intctrl(spi_imx, 0);
1141	complete(&spi_imx->xfer_done);
1142
1143	return IRQ_HANDLED;
1144}
1145
1146static int spi_imx_dma_configure(struct spi_master *master)
1147{
1148	int ret;
1149	enum dma_slave_buswidth buswidth;
1150	struct dma_slave_config rx = {}, tx = {};
1151	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1152
1153	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1154	case 4:
1155		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1156		break;
1157	case 2:
1158		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1159		break;
1160	case 1:
1161		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1162		break;
1163	default:
1164		return -EINVAL;
1165	}
1166
1167	tx.direction = DMA_MEM_TO_DEV;
1168	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1169	tx.dst_addr_width = buswidth;
1170	tx.dst_maxburst = spi_imx->wml;
1171	ret = dmaengine_slave_config(master->dma_tx, &tx);
1172	if (ret) {
1173		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1174		return ret;
1175	}
1176
1177	rx.direction = DMA_DEV_TO_MEM;
1178	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1179	rx.src_addr_width = buswidth;
1180	rx.src_maxburst = spi_imx->wml;
1181	ret = dmaengine_slave_config(master->dma_rx, &rx);
1182	if (ret) {
1183		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1184		return ret;
1185	}
1186
1187	return 0;
1188}
1189
1190static int spi_imx_setupxfer(struct spi_device *spi,
1191				 struct spi_transfer *t)
1192{
1193	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
1194
1195	if (!t)
1196		return 0;
1197
1198	spi_imx->bits_per_word = t->bits_per_word;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1199
1200	/*
1201	 * Initialize the functions for transfer. To transfer non byte-aligned
1202	 * words, we have to use multiple word-size bursts, we can't use
1203	 * dynamic_burst in that case.
1204	 */
1205	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1206	    (spi_imx->bits_per_word == 8 ||
1207	    spi_imx->bits_per_word == 16 ||
1208	    spi_imx->bits_per_word == 32)) {
1209
1210		spi_imx->rx = spi_imx_buf_rx_swap;
1211		spi_imx->tx = spi_imx_buf_tx_swap;
1212		spi_imx->dynamic_burst = 1;
1213
1214	} else {
1215		if (spi_imx->bits_per_word <= 8) {
1216			spi_imx->rx = spi_imx_buf_rx_u8;
1217			spi_imx->tx = spi_imx_buf_tx_u8;
1218		} else if (spi_imx->bits_per_word <= 16) {
1219			spi_imx->rx = spi_imx_buf_rx_u16;
1220			spi_imx->tx = spi_imx_buf_tx_u16;
1221		} else {
1222			spi_imx->rx = spi_imx_buf_rx_u32;
1223			spi_imx->tx = spi_imx_buf_tx_u32;
1224		}
1225		spi_imx->dynamic_burst = 0;
1226	}
1227
1228	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1229		spi_imx->usedma = true;
1230	else
1231		spi_imx->usedma = false;
1232
1233	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1234		spi_imx->rx = mx53_ecspi_rx_slave;
1235		spi_imx->tx = mx53_ecspi_tx_slave;
1236		spi_imx->slave_burst = t->len;
1237	}
1238
1239	spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
1240
1241	return 0;
1242}
1243
1244static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1245{
1246	struct spi_master *master = spi_imx->bitbang.master;
1247
1248	if (master->dma_rx) {
1249		dma_release_channel(master->dma_rx);
1250		master->dma_rx = NULL;
1251	}
1252
1253	if (master->dma_tx) {
1254		dma_release_channel(master->dma_tx);
1255		master->dma_tx = NULL;
1256	}
1257}
1258
1259static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1260			     struct spi_master *master)
1261{
1262	int ret;
1263
1264	/* use pio mode for i.mx6dl chip TKT238285 */
1265	if (of_machine_is_compatible("fsl,imx6dl"))
1266		return 0;
1267
1268	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1269
1270	/* Prepare for TX DMA: */
1271	master->dma_tx = dma_request_chan(dev, "tx");
1272	if (IS_ERR(master->dma_tx)) {
1273		ret = PTR_ERR(master->dma_tx);
1274		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1275		master->dma_tx = NULL;
1276		goto err;
1277	}
1278
1279	/* Prepare for RX : */
1280	master->dma_rx = dma_request_chan(dev, "rx");
1281	if (IS_ERR(master->dma_rx)) {
1282		ret = PTR_ERR(master->dma_rx);
1283		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1284		master->dma_rx = NULL;
1285		goto err;
1286	}
1287
1288	init_completion(&spi_imx->dma_rx_completion);
1289	init_completion(&spi_imx->dma_tx_completion);
1290	master->can_dma = spi_imx_can_dma;
1291	master->max_dma_len = MAX_SDMA_BD_BYTES;
1292	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1293					 SPI_MASTER_MUST_TX;
1294
1295	return 0;
1296err:
1297	spi_imx_sdma_exit(spi_imx);
1298	return ret;
1299}
1300
1301static void spi_imx_dma_rx_callback(void *cookie)
1302{
1303	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1304
1305	complete(&spi_imx->dma_rx_completion);
1306}
1307
1308static void spi_imx_dma_tx_callback(void *cookie)
1309{
1310	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1311
1312	complete(&spi_imx->dma_tx_completion);
1313}
1314
1315static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1316{
1317	unsigned long timeout = 0;
1318
1319	/* Time with actual data transfer and CS change delay related to HW */
1320	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1321
1322	/* Add extra second for scheduler related activities */
1323	timeout += 1;
1324
1325	/* Double calculated timeout */
1326	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1327}
1328
1329static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1330				struct spi_transfer *transfer)
1331{
1332	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1333	unsigned long transfer_timeout;
1334	unsigned long timeout;
1335	struct spi_master *master = spi_imx->bitbang.master;
1336	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1337	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1338	unsigned int bytes_per_word, i;
1339	int ret;
1340
1341	/* Get the right burst length from the last sg to ensure no tail data */
1342	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1343	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1344		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1345			break;
1346	}
1347	/* Use 1 as wml in case no available burst length got */
1348	if (i == 0)
1349		i = 1;
1350
1351	spi_imx->wml =  i;
1352
1353	ret = spi_imx_dma_configure(master);
1354	if (ret)
1355		goto dma_failure_no_start;
1356
1357	if (!spi_imx->devtype_data->setup_wml) {
1358		dev_err(spi_imx->dev, "No setup_wml()?\n");
1359		ret = -EINVAL;
1360		goto dma_failure_no_start;
1361	}
1362	spi_imx->devtype_data->setup_wml(spi_imx);
1363
1364	/*
1365	 * The TX DMA setup starts the transfer, so make sure RX is configured
1366	 * before TX.
1367	 */
1368	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1369				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1370				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1371	if (!desc_rx) {
1372		ret = -EINVAL;
1373		goto dma_failure_no_start;
1374	}
1375
1376	desc_rx->callback = spi_imx_dma_rx_callback;
1377	desc_rx->callback_param = (void *)spi_imx;
1378	dmaengine_submit(desc_rx);
1379	reinit_completion(&spi_imx->dma_rx_completion);
1380	dma_async_issue_pending(master->dma_rx);
1381
1382	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1383				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1384				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1385	if (!desc_tx) {
1386		dmaengine_terminate_all(master->dma_tx);
1387		dmaengine_terminate_all(master->dma_rx);
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/* fallback to pio */
1420dma_failure_no_start:
1421	transfer->error |= SPI_TRANS_FAIL_NO_START;
1422	return ret;
1423}
1424
1425static int spi_imx_pio_transfer(struct spi_device *spi,
1426				struct spi_transfer *transfer)
1427{
1428	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1429	unsigned long transfer_timeout;
1430	unsigned long timeout;
1431
1432	spi_imx->tx_buf = transfer->tx_buf;
1433	spi_imx->rx_buf = transfer->rx_buf;
1434	spi_imx->count = transfer->len;
1435	spi_imx->txfifo = 0;
1436	spi_imx->remainder = 0;
1437
1438	reinit_completion(&spi_imx->xfer_done);
1439
1440	spi_imx_push(spi_imx);
1441
1442	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1443
1444	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1445
1446	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1447					      transfer_timeout);
1448	if (!timeout) {
1449		dev_err(&spi->dev, "I/O Error in PIO\n");
1450		spi_imx->devtype_data->reset(spi_imx);
1451		return -ETIMEDOUT;
1452	}
1453
1454	return transfer->len;
1455}
1456
1457static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1458				      struct spi_transfer *transfer)
1459{
1460	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1461	int ret = transfer->len;
1462
1463	if (is_imx53_ecspi(spi_imx) &&
1464	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1465		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1466			MX53_MAX_TRANSFER_BYTES);
1467		return -EMSGSIZE;
1468	}
1469
1470	spi_imx->tx_buf = transfer->tx_buf;
1471	spi_imx->rx_buf = transfer->rx_buf;
1472	spi_imx->count = transfer->len;
1473	spi_imx->txfifo = 0;
1474	spi_imx->remainder = 0;
1475
1476	reinit_completion(&spi_imx->xfer_done);
1477	spi_imx->slave_aborted = false;
1478
1479	spi_imx_push(spi_imx);
1480
1481	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1482
1483	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1484	    spi_imx->slave_aborted) {
1485		dev_dbg(&spi->dev, "interrupted\n");
1486		ret = -EINTR;
1487	}
1488
1489	/* ecspi has a HW issue when works in Slave mode,
1490	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1491	 * ECSPI_TXDATA keeps shift out the last word data,
1492	 * so we have to disable ECSPI when in slave mode after the
1493	 * transfer completes
1494	 */
1495	if (spi_imx->devtype_data->disable)
1496		spi_imx->devtype_data->disable(spi_imx);
1497
1498	return ret;
1499}
1500
1501static int spi_imx_transfer(struct spi_device *spi,
1502				struct spi_transfer *transfer)
1503{
1504	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
1505
1506	/* flush rxfifo before transfer */
1507	while (spi_imx->devtype_data->rx_available(spi_imx))
1508		readl(spi_imx->base + MXC_CSPIRXDATA);
1509
1510	if (spi_imx->slave_mode)
1511		return spi_imx_pio_transfer_slave(spi, transfer);
1512
1513	if (spi_imx->usedma)
1514		return spi_imx_dma_transfer(spi_imx, transfer);
1515
1516	return spi_imx_pio_transfer(spi, transfer);
1517}
1518
1519static int spi_imx_setup(struct spi_device *spi)
1520{
1521	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1522		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1523
1524	return 0;
1525}
1526
1527static void spi_imx_cleanup(struct spi_device *spi)
1528{
1529}
1530
1531static int
1532spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1533{
1534	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1535	int ret;
1536
1537	ret = pm_runtime_get_sync(spi_imx->dev);
1538	if (ret < 0) {
1539		dev_err(spi_imx->dev, "failed to enable clock\n");
1540		return ret;
1541	}
1542
1543	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1544	if (ret) {
1545		pm_runtime_mark_last_busy(spi_imx->dev);
1546		pm_runtime_put_autosuspend(spi_imx->dev);
1547	}
1548
1549	return ret;
1550}
1551
1552static int
1553spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1554{
1555	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1556
1557	pm_runtime_mark_last_busy(spi_imx->dev);
1558	pm_runtime_put_autosuspend(spi_imx->dev);
1559	return 0;
1560}
1561
1562static int spi_imx_slave_abort(struct spi_master *master)
1563{
1564	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1565
1566	spi_imx->slave_aborted = true;
1567	complete(&spi_imx->xfer_done);
1568
1569	return 0;
1570}
1571
1572static int spi_imx_probe(struct platform_device *pdev)
1573{
1574	struct device_node *np = pdev->dev.of_node;
1575	const struct of_device_id *of_id =
1576			of_match_device(spi_imx_dt_ids, &pdev->dev);
 
 
1577	struct spi_master *master;
1578	struct spi_imx_data *spi_imx;
1579	struct resource *res;
1580	int ret, irq, spi_drctl;
1581	const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
1582		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1583	bool slave_mode;
1584	u32 val;
1585
1586	slave_mode = devtype_data->has_slavemode &&
1587			of_property_read_bool(np, "spi-slave");
1588	if (slave_mode)
1589		master = spi_alloc_slave(&pdev->dev,
1590					 sizeof(struct spi_imx_data));
1591	else
1592		master = spi_alloc_master(&pdev->dev,
1593					  sizeof(struct spi_imx_data));
1594	if (!master)
1595		return -ENOMEM;
1596
1597	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1598	if ((ret < 0) || (spi_drctl >= 0x3)) {
1599		/* '11' is reserved */
1600		spi_drctl = 0;
1601	}
1602
 
 
 
 
 
 
 
 
 
1603	platform_set_drvdata(pdev, master);
1604
1605	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1606	master->bus_num = np ? -1 : pdev->id;
1607	master->use_gpio_descriptors = true;
1608
1609	spi_imx = spi_master_get_devdata(master);
1610	spi_imx->bitbang.master = master;
1611	spi_imx->dev = &pdev->dev;
1612	spi_imx->slave_mode = slave_mode;
1613
1614	spi_imx->devtype_data = devtype_data;
1615
1616	/*
1617	 * Get number of chip selects from device properties. This can be
1618	 * coming from device tree or boardfiles, if it is not defined,
1619	 * a default value of 3 chip selects will be used, as all the legacy
1620	 * board files have <= 3 chip selects.
1621	 */
1622	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1623		master->num_chipselect = val;
1624	else
1625		master->num_chipselect = 3;
 
 
 
 
 
 
 
 
 
 
1626
 
1627	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1628	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1629	spi_imx->bitbang.master->setup = spi_imx_setup;
1630	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1631	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1632	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1633	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1634	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1635					     | SPI_NO_CS;
1636	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1637	    is_imx53_ecspi(spi_imx))
1638		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1639
1640	spi_imx->spi_drctl = spi_drctl;
1641
1642	init_completion(&spi_imx->xfer_done);
1643
 
 
 
1644	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1645	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1646	if (IS_ERR(spi_imx->base)) {
1647		ret = PTR_ERR(spi_imx->base);
1648		goto out_master_put;
1649	}
1650	spi_imx->base_phys = res->start;
1651
1652	irq = platform_get_irq(pdev, 0);
1653	if (irq < 0) {
1654		ret = irq;
1655		goto out_master_put;
1656	}
1657
1658	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1659			       dev_name(&pdev->dev), spi_imx);
1660	if (ret) {
1661		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1662		goto out_master_put;
1663	}
1664
1665	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1666	if (IS_ERR(spi_imx->clk_ipg)) {
1667		ret = PTR_ERR(spi_imx->clk_ipg);
1668		goto out_master_put;
1669	}
1670
1671	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1672	if (IS_ERR(spi_imx->clk_per)) {
1673		ret = PTR_ERR(spi_imx->clk_per);
1674		goto out_master_put;
1675	}
1676
1677	pm_runtime_enable(spi_imx->dev);
1678	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1679	pm_runtime_use_autosuspend(spi_imx->dev);
1680
1681	ret = pm_runtime_get_sync(spi_imx->dev);
1682	if (ret < 0) {
1683		dev_err(spi_imx->dev, "failed to enable clock\n");
1684		goto out_runtime_pm_put;
1685	}
1686
1687	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1688	/*
1689	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1690	 * if validated on other chips.
1691	 */
1692	if (spi_imx->devtype_data->has_dmamode) {
1693		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1694		if (ret == -EPROBE_DEFER)
1695			goto out_runtime_pm_put;
1696
1697		if (ret < 0)
1698			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1699				ret);
1700	}
1701
1702	spi_imx->devtype_data->reset(spi_imx);
1703
1704	spi_imx->devtype_data->intctrl(spi_imx, 0);
1705
1706	master->dev.of_node = pdev->dev.of_node;
1707	ret = spi_bitbang_start(&spi_imx->bitbang);
1708	if (ret) {
1709		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1710		goto out_runtime_pm_put;
1711	}
1712
1713	dev_info(&pdev->dev, "probed\n");
1714
1715	pm_runtime_mark_last_busy(spi_imx->dev);
1716	pm_runtime_put_autosuspend(spi_imx->dev);
1717
1718	return ret;
1719
1720out_runtime_pm_put:
1721	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1722	pm_runtime_put_sync(spi_imx->dev);
1723	pm_runtime_disable(spi_imx->dev);
 
 
 
 
 
 
 
 
 
1724out_master_put:
1725	spi_master_put(master);
1726
 
1727	return ret;
1728}
1729
1730static int spi_imx_remove(struct platform_device *pdev)
1731{
1732	struct spi_master *master = platform_get_drvdata(pdev);
 
1733	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1734	int ret;
1735
1736	spi_bitbang_stop(&spi_imx->bitbang);
1737
1738	ret = pm_runtime_get_sync(spi_imx->dev);
1739	if (ret < 0) {
1740		dev_err(spi_imx->dev, "failed to enable clock\n");
1741		return ret;
1742	}
1743
1744	writel(0, spi_imx->base + MXC_CSPICTRL);
 
 
 
 
 
 
 
 
1745
1746	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1747	pm_runtime_put_sync(spi_imx->dev);
1748	pm_runtime_disable(spi_imx->dev);
1749
1750	spi_imx_sdma_exit(spi_imx);
1751	spi_master_put(master);
1752
1753	return 0;
1754}
1755
1756static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1757{
1758	struct spi_master *master = dev_get_drvdata(dev);
1759	struct spi_imx_data *spi_imx;
1760	int ret;
1761
1762	spi_imx = spi_master_get_devdata(master);
1763
1764	ret = clk_prepare_enable(spi_imx->clk_per);
1765	if (ret)
1766		return ret;
1767
1768	ret = clk_prepare_enable(spi_imx->clk_ipg);
1769	if (ret) {
1770		clk_disable_unprepare(spi_imx->clk_per);
1771		return ret;
1772	}
1773
1774	return 0;
1775}
1776
1777static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1778{
1779	struct spi_master *master = dev_get_drvdata(dev);
1780	struct spi_imx_data *spi_imx;
1781
1782	spi_imx = spi_master_get_devdata(master);
1783
1784	clk_disable_unprepare(spi_imx->clk_per);
1785	clk_disable_unprepare(spi_imx->clk_ipg);
1786
1787	return 0;
1788}
1789
1790static int __maybe_unused spi_imx_suspend(struct device *dev)
1791{
1792	pinctrl_pm_select_sleep_state(dev);
1793	return 0;
1794}
1795
1796static int __maybe_unused spi_imx_resume(struct device *dev)
1797{
1798	pinctrl_pm_select_default_state(dev);
1799	return 0;
1800}
1801
1802static const struct dev_pm_ops imx_spi_pm = {
1803	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1804				spi_imx_runtime_resume, NULL)
1805	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1806};
1807
1808static struct platform_driver spi_imx_driver = {
1809	.driver = {
1810		   .name = DRIVER_NAME,
 
1811		   .of_match_table = spi_imx_dt_ids,
1812		   .pm = &imx_spi_pm,
1813	},
1814	.id_table = spi_imx_devtype,
1815	.probe = spi_imx_probe,
1816	.remove = spi_imx_remove,
1817};
1818module_platform_driver(spi_imx_driver);
1819
1820MODULE_DESCRIPTION("SPI Controller driver");
 
 
 
 
 
 
 
 
 
 
 
 
 
1821MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1822MODULE_LICENSE("GPL");
1823MODULE_ALIAS("platform:" DRIVER_NAME);
v3.1
  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/err.h>
 25#include <linux/gpio.h>
 26#include <linux/init.h>
 27#include <linux/interrupt.h>
 28#include <linux/io.h>
 29#include <linux/irq.h>
 30#include <linux/kernel.h>
 31#include <linux/module.h>
 
 32#include <linux/platform_device.h>
 
 33#include <linux/slab.h>
 34#include <linux/spi/spi.h>
 35#include <linux/spi/spi_bitbang.h>
 36#include <linux/types.h>
 37#include <linux/of.h>
 38#include <linux/of_device.h>
 39#include <linux/of_gpio.h>
 40
 41#include <mach/spi.h>
 42
 43#define DRIVER_NAME "spi_imx"
 44
 
 
 
 
 
 
 45#define MXC_CSPIRXDATA		0x00
 46#define MXC_CSPITXDATA		0x04
 47#define MXC_CSPICTRL		0x08
 48#define MXC_CSPIINT		0x0c
 49#define MXC_RESET		0x1c
 50
 51/* generic defines to abstract from the different register layouts */
 52#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
 53#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
 
 54
 55struct spi_imx_config {
 56	unsigned int speed_hz;
 57	unsigned int bpw;
 58	unsigned int mode;
 59	u8 cs;
 60};
 61
 62enum spi_imx_devtype {
 63	IMX1_CSPI,
 64	IMX21_CSPI,
 65	IMX27_CSPI,
 66	IMX31_CSPI,
 67	IMX35_CSPI,	/* CSPI on all i.mx except above */
 68	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
 
 69};
 70
 71struct spi_imx_data;
 72
 73struct spi_imx_devtype_data {
 74	void (*intctrl)(struct spi_imx_data *, int);
 75	int (*config)(struct spi_imx_data *, struct spi_imx_config *);
 
 
 76	void (*trigger)(struct spi_imx_data *);
 77	int (*rx_available)(struct spi_imx_data *);
 78	void (*reset)(struct spi_imx_data *);
 
 
 
 
 
 
 
 79	enum spi_imx_devtype devtype;
 80};
 81
 82struct spi_imx_data {
 83	struct spi_bitbang bitbang;
 
 84
 85	struct completion xfer_done;
 86	void *base;
 87	int irq;
 88	struct clk *clk;
 
 
 89	unsigned long spi_clk;
 
 
 
 
 90
 91	unsigned int count;
 92	void (*tx)(struct spi_imx_data *);
 93	void (*rx)(struct spi_imx_data *);
 94	void *rx_buf;
 95	const void *tx_buf;
 96	unsigned int txfifo; /* number of words pushed in tx FIFO */
 
 97
 98	struct spi_imx_devtype_data *devtype_data;
 99	int chipselect[0];
 
 
 
 
 
 
 
 
 
 
100};
101
102static inline int is_imx27_cspi(struct spi_imx_data *d)
103{
104	return d->devtype_data->devtype == IMX27_CSPI;
105}
106
107static inline int is_imx35_cspi(struct spi_imx_data *d)
108{
109	return d->devtype_data->devtype == IMX35_CSPI;
110}
111
112static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
 
 
 
 
 
113{
114	return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8;
115}
116
117#define MXC_SPI_BUF_RX(type)						\
118static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
119{									\
120	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
121									\
122	if (spi_imx->rx_buf) {						\
123		*(type *)spi_imx->rx_buf = val;				\
124		spi_imx->rx_buf += sizeof(type);			\
125	}								\
 
 
126}
127
128#define MXC_SPI_BUF_TX(type)						\
129static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
130{									\
131	type val = 0;							\
132									\
133	if (spi_imx->tx_buf) {						\
134		val = *(type *)spi_imx->tx_buf;				\
135		spi_imx->tx_buf += sizeof(type);			\
136	}								\
137									\
138	spi_imx->count -= sizeof(type);					\
139									\
140	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
141}
142
143MXC_SPI_BUF_RX(u8)
144MXC_SPI_BUF_TX(u8)
145MXC_SPI_BUF_RX(u16)
146MXC_SPI_BUF_TX(u16)
147MXC_SPI_BUF_RX(u32)
148MXC_SPI_BUF_TX(u32)
149
150/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
151 * (which is currently not the case in this driver)
152 */
153static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
154	256, 384, 512, 768, 1024};
155
156/* MX21, MX27 */
157static unsigned int spi_imx_clkdiv_1(unsigned int fin,
158		unsigned int fspi, unsigned int max)
159{
160	int i;
161
162	for (i = 2; i < max; i++)
163		if (fspi * mxc_clkdivs[i] >= fin)
164			return i;
165
166	return max;
 
167}
168
169/* MX1, MX31, MX35, MX51 CSPI */
170static unsigned int spi_imx_clkdiv_2(unsigned int fin,
171		unsigned int fspi)
172{
173	int i, div = 4;
174
175	for (i = 0; i < 7; i++) {
176		if (fspi * div >= fin)
177			return i;
178		div <<= 1;
179	}
180
181	return 7;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
182}
183
184#define MX51_ECSPI_CTRL		0x08
185#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
186#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 
187#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 
188#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
189#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
190#define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
191#define MX51_ECSPI_CTRL_BL_OFFSET	20
 
192
193#define MX51_ECSPI_CONFIG	0x0c
194#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
195#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
196#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
197#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
 
198
199#define MX51_ECSPI_INT		0x10
200#define MX51_ECSPI_INT_TEEN		(1 <<  0)
201#define MX51_ECSPI_INT_RREN		(1 <<  3)
 
 
 
 
 
 
 
 
 
 
202
203#define MX51_ECSPI_STAT		0x18
204#define MX51_ECSPI_STAT_RR		(1 <<  3)
205
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
206/* MX51 eCSPI */
207static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi)
 
208{
209	/*
210	 * there are two 4-bit dividers, the pre-divider divides by
211	 * $pre, the post-divider by 2^$post
212	 */
213	unsigned int pre, post;
 
214
215	if (unlikely(fspi > fin))
216		return 0;
217
218	post = fls(fin) - fls(fspi);
219	if (fin > fspi << post)
220		post++;
221
222	/* now we have: (fin <= fspi << post) with post being minimal */
223
224	post = max(4U, post) - 4;
225	if (unlikely(post > 0xf)) {
226		pr_err("%s: cannot set clock freq: %u (base freq: %u)\n",
227				__func__, fspi, fin);
228		return 0xff;
229	}
230
231	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
232
233	pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
234			__func__, fin, fspi, post, pre);
 
 
 
 
235	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
236		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
237}
238
239static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
240{
241	unsigned val = 0;
242
243	if (enable & MXC_INT_TE)
244		val |= MX51_ECSPI_INT_TEEN;
245
246	if (enable & MXC_INT_RR)
247		val |= MX51_ECSPI_INT_RREN;
248
 
 
 
249	writel(val, spi_imx->base + MX51_ECSPI_INT);
250}
251
252static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
253{
254	u32 reg;
255
256	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
257	reg |= MX51_ECSPI_CTRL_XCH;
258	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
259}
260
261static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
262		struct spi_imx_config *config)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
263{
264	u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0;
 
 
 
 
 
 
 
 
 
265
266	/*
267	 * The hardware seems to have a race condition when changing modes. The
268	 * current assumption is that the selection of the channel arrives
269	 * earlier in the hardware than the mode bits when they are written at
270	 * the same time.
271	 * So set master mode for all channels as we do not support slave mode.
272	 */
273	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 
274
275	/* set clock speed */
276	ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
277
278	/* set chip select to use */
279	ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
 
 
280
281	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
282
283	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
 
284
285	if (config->mode & SPI_CPHA)
286		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
 
 
 
 
 
 
 
 
 
 
 
 
 
287
288	if (config->mode & SPI_CPOL)
289		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
 
 
 
290
291	if (config->mode & SPI_CS_HIGH)
292		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
293
294	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
295	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
296
297	return 0;
298}
299
300static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 
 
 
 
 
 
 
 
 
 
 
 
 
301{
302	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
303}
304
305static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
306{
307	/* drain receive buffer */
308	while (mx51_ecspi_rx_available(spi_imx))
309		readl(spi_imx->base + MXC_CSPIRXDATA);
310}
311
312#define MX31_INTREG_TEEN	(1 << 0)
313#define MX31_INTREG_RREN	(1 << 3)
314
315#define MX31_CSPICTRL_ENABLE	(1 << 0)
316#define MX31_CSPICTRL_MASTER	(1 << 1)
317#define MX31_CSPICTRL_XCH	(1 << 2)
 
318#define MX31_CSPICTRL_POL	(1 << 4)
319#define MX31_CSPICTRL_PHA	(1 << 5)
320#define MX31_CSPICTRL_SSCTL	(1 << 6)
321#define MX31_CSPICTRL_SSPOL	(1 << 7)
322#define MX31_CSPICTRL_BC_SHIFT	8
323#define MX35_CSPICTRL_BL_SHIFT	20
324#define MX31_CSPICTRL_CS_SHIFT	24
325#define MX35_CSPICTRL_CS_SHIFT	12
326#define MX31_CSPICTRL_DR_SHIFT	16
327
 
 
 
 
328#define MX31_CSPISTATUS		0x14
329#define MX31_STATUS_RR		(1 << 3)
330
 
 
 
331/* These functions also work for the i.MX35, but be aware that
332 * the i.MX35 has a slightly different register layout for bits
333 * we do not use here.
334 */
335static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
336{
337	unsigned int val = 0;
338
339	if (enable & MXC_INT_TE)
340		val |= MX31_INTREG_TEEN;
341	if (enable & MXC_INT_RR)
342		val |= MX31_INTREG_RREN;
343
344	writel(val, spi_imx->base + MXC_CSPIINT);
345}
346
347static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
348{
349	unsigned int reg;
350
351	reg = readl(spi_imx->base + MXC_CSPICTRL);
352	reg |= MX31_CSPICTRL_XCH;
353	writel(reg, spi_imx->base + MXC_CSPICTRL);
354}
355
356static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
357		struct spi_imx_config *config)
 
 
 
 
 
 
 
358{
359	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
360	int cs = spi_imx->chipselect[config->cs];
361
362	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
363		MX31_CSPICTRL_DR_SHIFT;
 
364
365	if (is_imx35_cspi(spi_imx)) {
366		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
367		reg |= MX31_CSPICTRL_SSCTL;
368	} else {
369		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
370	}
371
372	if (config->mode & SPI_CPHA)
373		reg |= MX31_CSPICTRL_PHA;
374	if (config->mode & SPI_CPOL)
375		reg |= MX31_CSPICTRL_POL;
376	if (config->mode & SPI_CS_HIGH)
377		reg |= MX31_CSPICTRL_SSPOL;
378	if (cs < 0)
379		reg |= (cs + 32) <<
380			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
381						  MX31_CSPICTRL_CS_SHIFT);
382
 
 
 
383	writel(reg, spi_imx->base + MXC_CSPICTRL);
384
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
385	return 0;
386}
387
388static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
389{
390	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
391}
392
393static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
394{
395	/* drain receive buffer */
396	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
397		readl(spi_imx->base + MXC_CSPIRXDATA);
398}
399
400#define MX21_INTREG_RR		(1 << 4)
401#define MX21_INTREG_TEEN	(1 << 9)
402#define MX21_INTREG_RREN	(1 << 13)
403
404#define MX21_CSPICTRL_POL	(1 << 5)
405#define MX21_CSPICTRL_PHA	(1 << 6)
406#define MX21_CSPICTRL_SSPOL	(1 << 8)
407#define MX21_CSPICTRL_XCH	(1 << 9)
408#define MX21_CSPICTRL_ENABLE	(1 << 10)
409#define MX21_CSPICTRL_MASTER	(1 << 11)
410#define MX21_CSPICTRL_DR_SHIFT	14
411#define MX21_CSPICTRL_CS_SHIFT	19
412
413static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
414{
415	unsigned int val = 0;
416
417	if (enable & MXC_INT_TE)
418		val |= MX21_INTREG_TEEN;
419	if (enable & MXC_INT_RR)
420		val |= MX21_INTREG_RREN;
421
422	writel(val, spi_imx->base + MXC_CSPIINT);
423}
424
425static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
426{
427	unsigned int reg;
428
429	reg = readl(spi_imx->base + MXC_CSPICTRL);
430	reg |= MX21_CSPICTRL_XCH;
431	writel(reg, spi_imx->base + MXC_CSPICTRL);
432}
433
434static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
435		struct spi_imx_config *config)
 
 
 
 
 
 
 
436{
437	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
438	int cs = spi_imx->chipselect[config->cs];
439	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 
440
441	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
442		MX21_CSPICTRL_DR_SHIFT;
443	reg |= config->bpw - 1;
444
445	if (config->mode & SPI_CPHA)
 
 
446		reg |= MX21_CSPICTRL_PHA;
447	if (config->mode & SPI_CPOL)
448		reg |= MX21_CSPICTRL_POL;
449	if (config->mode & SPI_CS_HIGH)
450		reg |= MX21_CSPICTRL_SSPOL;
451	if (cs < 0)
452		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
453
454	writel(reg, spi_imx->base + MXC_CSPICTRL);
455
456	return 0;
457}
458
459static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
460{
461	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
462}
463
464static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
465{
466	writel(1, spi_imx->base + MXC_RESET);
467}
468
469#define MX1_INTREG_RR		(1 << 3)
470#define MX1_INTREG_TEEN		(1 << 8)
471#define MX1_INTREG_RREN		(1 << 11)
472
473#define MX1_CSPICTRL_POL	(1 << 4)
474#define MX1_CSPICTRL_PHA	(1 << 5)
475#define MX1_CSPICTRL_XCH	(1 << 8)
476#define MX1_CSPICTRL_ENABLE	(1 << 9)
477#define MX1_CSPICTRL_MASTER	(1 << 10)
478#define MX1_CSPICTRL_DR_SHIFT	13
479
480static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
481{
482	unsigned int val = 0;
483
484	if (enable & MXC_INT_TE)
485		val |= MX1_INTREG_TEEN;
486	if (enable & MXC_INT_RR)
487		val |= MX1_INTREG_RREN;
488
489	writel(val, spi_imx->base + MXC_CSPIINT);
490}
491
492static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
493{
494	unsigned int reg;
495
496	reg = readl(spi_imx->base + MXC_CSPICTRL);
497	reg |= MX1_CSPICTRL_XCH;
498	writel(reg, spi_imx->base + MXC_CSPICTRL);
499}
500
501static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
502		struct spi_imx_config *config)
 
 
 
 
 
 
 
503{
504	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 
505
506	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
507		MX1_CSPICTRL_DR_SHIFT;
508	reg |= config->bpw - 1;
509
510	if (config->mode & SPI_CPHA)
 
 
511		reg |= MX1_CSPICTRL_PHA;
512	if (config->mode & SPI_CPOL)
513		reg |= MX1_CSPICTRL_POL;
514
515	writel(reg, spi_imx->base + MXC_CSPICTRL);
516
517	return 0;
518}
519
520static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
521{
522	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
523}
524
525static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
526{
527	writel(1, spi_imx->base + MXC_RESET);
528}
529
530static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
531	.intctrl = mx1_intctrl,
532	.config = mx1_config,
 
533	.trigger = mx1_trigger,
534	.rx_available = mx1_rx_available,
535	.reset = mx1_reset,
 
 
 
 
536	.devtype = IMX1_CSPI,
537};
538
539static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
540	.intctrl = mx21_intctrl,
541	.config = mx21_config,
 
542	.trigger = mx21_trigger,
543	.rx_available = mx21_rx_available,
544	.reset = mx21_reset,
 
 
 
 
545	.devtype = IMX21_CSPI,
546};
547
548static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
549	/* i.mx27 cspi shares the functions with i.mx21 one */
550	.intctrl = mx21_intctrl,
551	.config = mx21_config,
 
552	.trigger = mx21_trigger,
553	.rx_available = mx21_rx_available,
554	.reset = mx21_reset,
 
 
 
 
555	.devtype = IMX27_CSPI,
556};
557
558static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
559	.intctrl = mx31_intctrl,
560	.config = mx31_config,
 
561	.trigger = mx31_trigger,
562	.rx_available = mx31_rx_available,
563	.reset = mx31_reset,
 
 
 
 
564	.devtype = IMX31_CSPI,
565};
566
567static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
568	/* i.mx35 and later cspi shares the functions with i.mx31 one */
569	.intctrl = mx31_intctrl,
570	.config = mx31_config,
 
571	.trigger = mx31_trigger,
572	.rx_available = mx31_rx_available,
573	.reset = mx31_reset,
 
 
 
 
574	.devtype = IMX35_CSPI,
575};
576
577static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
578	.intctrl = mx51_ecspi_intctrl,
579	.config = mx51_ecspi_config,
 
580	.trigger = mx51_ecspi_trigger,
581	.rx_available = mx51_ecspi_rx_available,
582	.reset = mx51_ecspi_reset,
 
 
 
 
 
 
 
583	.devtype = IMX51_ECSPI,
584};
585
586static struct platform_device_id spi_imx_devtype[] = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
587	{
588		.name = "imx1-cspi",
589		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
590	}, {
591		.name = "imx21-cspi",
592		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
593	}, {
594		.name = "imx27-cspi",
595		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
596	}, {
597		.name = "imx31-cspi",
598		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
599	}, {
600		.name = "imx35-cspi",
601		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
602	}, {
603		.name = "imx51-ecspi",
604		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
605	}, {
 
 
 
606		/* sentinel */
607	}
608};
609
610static const struct of_device_id spi_imx_dt_ids[] = {
611	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
612	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
613	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
614	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
615	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
616	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
 
617	{ /* sentinel */ }
618};
 
619
620static void spi_imx_chipselect(struct spi_device *spi, int is_active)
621{
622	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
623	int gpio = spi_imx->chipselect[spi->chip_select];
624	int active = is_active != BITBANG_CS_INACTIVE;
625	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
626
627	if (gpio < 0)
628		return;
629
630	gpio_set_value(gpio, dev_is_lowactive ^ active);
631}
632
633static void spi_imx_push(struct spi_imx_data *spi_imx)
634{
635	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
636		if (!spi_imx->count)
637			break;
 
 
 
 
638		spi_imx->tx(spi_imx);
639		spi_imx->txfifo++;
640	}
641
642	spi_imx->devtype_data->trigger(spi_imx);
 
643}
644
645static irqreturn_t spi_imx_isr(int irq, void *dev_id)
646{
647	struct spi_imx_data *spi_imx = dev_id;
648
649	while (spi_imx->devtype_data->rx_available(spi_imx)) {
 
650		spi_imx->rx(spi_imx);
651		spi_imx->txfifo--;
652	}
653
654	if (spi_imx->count) {
655		spi_imx_push(spi_imx);
656		return IRQ_HANDLED;
657	}
658
659	if (spi_imx->txfifo) {
660		/* No data left to push, but still waiting for rx data,
661		 * enable receive data available interrupt.
662		 */
663		spi_imx->devtype_data->intctrl(
664				spi_imx, MXC_INT_RR);
665		return IRQ_HANDLED;
666	}
667
668	spi_imx->devtype_data->intctrl(spi_imx, 0);
669	complete(&spi_imx->xfer_done);
670
671	return IRQ_HANDLED;
672}
673
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
674static int spi_imx_setupxfer(struct spi_device *spi,
675				 struct spi_transfer *t)
676{
677	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
678	struct spi_imx_config config;
679
680	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
681	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
682	config.mode = spi->mode;
683	config.cs = spi->chip_select;
684
685	if (!config.speed_hz)
686		config.speed_hz = spi->max_speed_hz;
687	if (!config.bpw)
688		config.bpw = spi->bits_per_word;
689	if (!config.speed_hz)
690		config.speed_hz = spi->max_speed_hz;
691
692	/* Initialize the functions for transfer */
693	if (config.bpw <= 8) {
694		spi_imx->rx = spi_imx_buf_rx_u8;
695		spi_imx->tx = spi_imx_buf_tx_u8;
696	} else if (config.bpw <= 16) {
697		spi_imx->rx = spi_imx_buf_rx_u16;
698		spi_imx->tx = spi_imx_buf_tx_u16;
699	} else if (config.bpw <= 32) {
700		spi_imx->rx = spi_imx_buf_rx_u32;
701		spi_imx->tx = spi_imx_buf_tx_u32;
702	} else
703		BUG();
704
705	spi_imx->devtype_data->config(spi_imx, &config);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
706
707	return 0;
 
 
 
708}
709
710static int spi_imx_transfer(struct spi_device *spi,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
711				struct spi_transfer *transfer)
712{
713	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
 
714
715	spi_imx->tx_buf = transfer->tx_buf;
716	spi_imx->rx_buf = transfer->rx_buf;
717	spi_imx->count = transfer->len;
718	spi_imx->txfifo = 0;
 
719
720	init_completion(&spi_imx->xfer_done);
721
722	spi_imx_push(spi_imx);
723
724	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
725
726	wait_for_completion(&spi_imx->xfer_done);
 
 
 
 
 
 
 
 
727
728	return transfer->len;
729}
730
731static int spi_imx_setup(struct spi_device *spi)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
732{
733	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
734	int gpio = spi_imx->chipselect[spi->chip_select];
735
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
736	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
737		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
738
739	if (gpio >= 0)
740		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
741
742	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
 
 
 
743
 
 
744	return 0;
745}
746
747static void spi_imx_cleanup(struct spi_device *spi)
748{
 
 
 
 
 
 
749}
750
751static int __devinit spi_imx_probe(struct platform_device *pdev)
752{
753	struct device_node *np = pdev->dev.of_node;
754	const struct of_device_id *of_id =
755			of_match_device(spi_imx_dt_ids, &pdev->dev);
756	struct spi_imx_master *mxc_platform_info =
757			dev_get_platdata(&pdev->dev);
758	struct spi_master *master;
759	struct spi_imx_data *spi_imx;
760	struct resource *res;
761	int i, ret, num_cs;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
762
763	if (!np && !mxc_platform_info) {
764		dev_err(&pdev->dev, "can't get the platform data\n");
765		return -EINVAL;
 
766	}
767
768	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
769	if (ret < 0)
770		num_cs = mxc_platform_info->num_chipselect;
771
772	master = spi_alloc_master(&pdev->dev,
773			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
774	if (!master)
775		return -ENOMEM;
776
777	platform_set_drvdata(pdev, master);
778
779	master->bus_num = pdev->id;
780	master->num_chipselect = num_cs;
 
781
782	spi_imx = spi_master_get_devdata(master);
783	spi_imx->bitbang.master = spi_master_get(master);
 
 
 
 
784
785	for (i = 0; i < master->num_chipselect; i++) {
786		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
787		if (cs_gpio < 0)
788			cs_gpio = mxc_platform_info->chipselect[i];
789
790		spi_imx->chipselect[i] = cs_gpio;
791		if (cs_gpio < 0)
792			continue;
793
794		ret = gpio_request(spi_imx->chipselect[i], DRIVER_NAME);
795		if (ret) {
796			while (i > 0) {
797				i--;
798				if (spi_imx->chipselect[i] >= 0)
799					gpio_free(spi_imx->chipselect[i]);
800			}
801			dev_err(&pdev->dev, "can't get cs gpios\n");
802			goto out_master_put;
803		}
804	}
805
806	spi_imx->bitbang.chipselect = spi_imx_chipselect;
807	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
808	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
809	spi_imx->bitbang.master->setup = spi_imx_setup;
810	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
811	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 
 
 
 
 
 
 
 
 
812
813	init_completion(&spi_imx->xfer_done);
814
815	spi_imx->devtype_data = of_id ? of_id->data :
816		(struct spi_imx_devtype_data *) pdev->id_entry->driver_data;
817
818	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
819	if (!res) {
820		dev_err(&pdev->dev, "can't get platform resource\n");
821		ret = -ENOMEM;
822		goto out_gpio_free;
823	}
 
824
825	if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
826		dev_err(&pdev->dev, "request_mem_region failed\n");
827		ret = -EBUSY;
828		goto out_gpio_free;
829	}
830
831	spi_imx->base = ioremap(res->start, resource_size(res));
832	if (!spi_imx->base) {
833		ret = -EINVAL;
834		goto out_release_mem;
 
835	}
836
837	spi_imx->irq = platform_get_irq(pdev, 0);
838	if (spi_imx->irq < 0) {
839		ret = -EINVAL;
840		goto out_iounmap;
841	}
842
843	ret = request_irq(spi_imx->irq, spi_imx_isr, 0, DRIVER_NAME, spi_imx);
844	if (ret) {
845		dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret);
846		goto out_iounmap;
847	}
848
849	spi_imx->clk = clk_get(&pdev->dev, NULL);
850	if (IS_ERR(spi_imx->clk)) {
851		dev_err(&pdev->dev, "unable to get clock\n");
852		ret = PTR_ERR(spi_imx->clk);
853		goto out_free_irq;
 
 
 
854	}
855
856	clk_enable(spi_imx->clk);
857	spi_imx->spi_clk = clk_get_rate(spi_imx->clk);
 
 
 
 
 
 
 
 
 
 
 
 
858
859	spi_imx->devtype_data->reset(spi_imx);
860
861	spi_imx->devtype_data->intctrl(spi_imx, 0);
862
863	master->dev.of_node = pdev->dev.of_node;
864	ret = spi_bitbang_start(&spi_imx->bitbang);
865	if (ret) {
866		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
867		goto out_clk_put;
868	}
869
870	dev_info(&pdev->dev, "probed\n");
871
 
 
 
872	return ret;
873
874out_clk_put:
875	clk_disable(spi_imx->clk);
876	clk_put(spi_imx->clk);
877out_free_irq:
878	free_irq(spi_imx->irq, spi_imx);
879out_iounmap:
880	iounmap(spi_imx->base);
881out_release_mem:
882	release_mem_region(res->start, resource_size(res));
883out_gpio_free:
884	for (i = 0; i < master->num_chipselect; i++)
885		if (spi_imx->chipselect[i] >= 0)
886			gpio_free(spi_imx->chipselect[i]);
887out_master_put:
888	spi_master_put(master);
889	kfree(master);
890	platform_set_drvdata(pdev, NULL);
891	return ret;
892}
893
894static int __devexit spi_imx_remove(struct platform_device *pdev)
895{
896	struct spi_master *master = platform_get_drvdata(pdev);
897	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
898	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
899	int i;
900
901	spi_bitbang_stop(&spi_imx->bitbang);
902
 
 
 
 
 
 
903	writel(0, spi_imx->base + MXC_CSPICTRL);
904	clk_disable(spi_imx->clk);
905	clk_put(spi_imx->clk);
906	free_irq(spi_imx->irq, spi_imx);
907	iounmap(spi_imx->base);
908
909	for (i = 0; i < master->num_chipselect; i++)
910		if (spi_imx->chipselect[i] >= 0)
911			gpio_free(spi_imx->chipselect[i]);
912
 
 
 
 
 
913	spi_master_put(master);
914
915	release_mem_region(res->start, resource_size(res));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
916
917	platform_set_drvdata(pdev, NULL);
 
918
 
 
 
919	return 0;
920}
921
 
 
 
 
 
 
 
 
 
 
 
 
922static struct platform_driver spi_imx_driver = {
923	.driver = {
924		   .name = DRIVER_NAME,
925		   .owner = THIS_MODULE,
926		   .of_match_table = spi_imx_dt_ids,
927		   },
 
928	.id_table = spi_imx_devtype,
929	.probe = spi_imx_probe,
930	.remove = __devexit_p(spi_imx_remove),
931};
 
932
933static int __init spi_imx_init(void)
934{
935	return platform_driver_register(&spi_imx_driver);
936}
937
938static void __exit spi_imx_exit(void)
939{
940	platform_driver_unregister(&spi_imx_driver);
941}
942
943module_init(spi_imx_init);
944module_exit(spi_imx_exit);
945
946MODULE_DESCRIPTION("SPI Master Controller driver");
947MODULE_AUTHOR("Sascha Hauer, Pengutronix");
948MODULE_LICENSE("GPL");