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   1/*
   2 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3 * Copyright (C) 2008 Juergen Beisert
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License
   7 * as published by the Free Software Foundation; either version 2
   8 * of the License, or (at your option) any later version.
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write to the
  16 * Free Software Foundation
  17 * 51 Franklin Street, Fifth Floor
  18 * Boston, MA  02110-1301, USA.
  19 */
  20
  21#include <linux/clk.h>
  22#include <linux/completion.h>
  23#include <linux/delay.h>
  24#include <linux/dmaengine.h>
  25#include <linux/dma-mapping.h>
  26#include <linux/err.h>
  27#include <linux/gpio.h>
  28#include <linux/interrupt.h>
  29#include <linux/io.h>
  30#include <linux/irq.h>
  31#include <linux/kernel.h>
  32#include <linux/module.h>
  33#include <linux/platform_device.h>
  34#include <linux/slab.h>
  35#include <linux/spi/spi.h>
  36#include <linux/spi/spi_bitbang.h>
  37#include <linux/types.h>
  38#include <linux/of.h>
  39#include <linux/of_device.h>
  40#include <linux/of_gpio.h>
  41
  42#include <linux/platform_data/dma-imx.h>
  43#include <linux/platform_data/spi-imx.h>
  44
  45#define DRIVER_NAME "spi_imx"
  46
  47#define MXC_CSPIRXDATA		0x00
  48#define MXC_CSPITXDATA		0x04
  49#define MXC_CSPICTRL		0x08
  50#define MXC_CSPIINT		0x0c
  51#define MXC_RESET		0x1c
  52
  53/* generic defines to abstract from the different register layouts */
  54#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
  55#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
  56
  57/* The maximum  bytes that a sdma BD can transfer.*/
  58#define MAX_SDMA_BD_BYTES  (1 << 15)
  59struct spi_imx_config {
  60	unsigned int speed_hz;
  61	unsigned int bpw;
  62	unsigned int mode;
  63	u8 cs;
  64};
  65
  66enum spi_imx_devtype {
  67	IMX1_CSPI,
  68	IMX21_CSPI,
  69	IMX27_CSPI,
  70	IMX31_CSPI,
  71	IMX35_CSPI,	/* CSPI on all i.mx except above */
  72	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
  73};
  74
  75struct spi_imx_data;
  76
  77struct spi_imx_devtype_data {
  78	void (*intctrl)(struct spi_imx_data *, int);
  79	int (*config)(struct spi_imx_data *, struct spi_imx_config *);
  80	void (*trigger)(struct spi_imx_data *);
  81	int (*rx_available)(struct spi_imx_data *);
  82	void (*reset)(struct spi_imx_data *);
  83	enum spi_imx_devtype devtype;
  84};
  85
  86struct spi_imx_data {
  87	struct spi_bitbang bitbang;
  88	struct device *dev;
  89
  90	struct completion xfer_done;
  91	void __iomem *base;
  92	unsigned long base_phys;
  93
  94	struct clk *clk_per;
  95	struct clk *clk_ipg;
  96	unsigned long spi_clk;
  97	unsigned int spi_bus_clk;
  98
  99	unsigned int bytes_per_word;
 100
 101	unsigned int count;
 102	void (*tx)(struct spi_imx_data *);
 103	void (*rx)(struct spi_imx_data *);
 104	void *rx_buf;
 105	const void *tx_buf;
 106	unsigned int txfifo; /* number of words pushed in tx FIFO */
 107
 108	/* DMA */
 109	bool usedma;
 110	u32 wml;
 111	struct completion dma_rx_completion;
 112	struct completion dma_tx_completion;
 113
 114	const struct spi_imx_devtype_data *devtype_data;
 115	int chipselect[0];
 116};
 117
 118static inline int is_imx27_cspi(struct spi_imx_data *d)
 119{
 120	return d->devtype_data->devtype == IMX27_CSPI;
 121}
 122
 123static inline int is_imx35_cspi(struct spi_imx_data *d)
 124{
 125	return d->devtype_data->devtype == IMX35_CSPI;
 126}
 127
 128static inline int is_imx51_ecspi(struct spi_imx_data *d)
 129{
 130	return d->devtype_data->devtype == IMX51_ECSPI;
 131}
 132
 133static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
 134{
 135	return is_imx51_ecspi(d) ? 64 : 8;
 136}
 137
 138#define MXC_SPI_BUF_RX(type)						\
 139static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 140{									\
 141	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 142									\
 143	if (spi_imx->rx_buf) {						\
 144		*(type *)spi_imx->rx_buf = val;				\
 145		spi_imx->rx_buf += sizeof(type);			\
 146	}								\
 147}
 148
 149#define MXC_SPI_BUF_TX(type)						\
 150static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 151{									\
 152	type val = 0;							\
 153									\
 154	if (spi_imx->tx_buf) {						\
 155		val = *(type *)spi_imx->tx_buf;				\
 156		spi_imx->tx_buf += sizeof(type);			\
 157	}								\
 158									\
 159	spi_imx->count -= sizeof(type);					\
 160									\
 161	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 162}
 163
 164MXC_SPI_BUF_RX(u8)
 165MXC_SPI_BUF_TX(u8)
 166MXC_SPI_BUF_RX(u16)
 167MXC_SPI_BUF_TX(u16)
 168MXC_SPI_BUF_RX(u32)
 169MXC_SPI_BUF_TX(u32)
 170
 171/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 172 * (which is currently not the case in this driver)
 173 */
 174static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 175	256, 384, 512, 768, 1024};
 176
 177/* MX21, MX27 */
 178static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 179		unsigned int fspi, unsigned int max)
 180{
 181	int i;
 182
 183	for (i = 2; i < max; i++)
 184		if (fspi * mxc_clkdivs[i] >= fin)
 185			return i;
 186
 187	return max;
 
 188}
 189
 190/* MX1, MX31, MX35, MX51 CSPI */
 191static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 192		unsigned int fspi)
 193{
 194	int i, div = 4;
 195
 196	for (i = 0; i < 7; i++) {
 197		if (fspi * div >= fin)
 198			return i;
 199		div <<= 1;
 200	}
 201
 202	return 7;
 
 
 203}
 204
 205static int spi_imx_bytes_per_word(const int bpw)
 206{
 207	return DIV_ROUND_UP(bpw, BITS_PER_BYTE);
 208}
 209
 210static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 211			 struct spi_transfer *transfer)
 212{
 213	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 214	unsigned int bpw;
 215
 216	if (!master->dma_rx)
 217		return false;
 218
 219	if (!transfer)
 220		return false;
 221
 222	bpw = transfer->bits_per_word;
 223	if (!bpw)
 224		bpw = spi->bits_per_word;
 225
 226	bpw = spi_imx_bytes_per_word(bpw);
 227
 228	if (bpw != 1 && bpw != 2 && bpw != 4)
 229		return false;
 230
 231	if (transfer->len < spi_imx->wml * bpw)
 232		return false;
 233
 234	if (transfer->len % (spi_imx->wml * bpw))
 235		return false;
 236
 237	return true;
 238}
 239
 240#define MX51_ECSPI_CTRL		0x08
 241#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
 242#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 243#define MX51_ECSPI_CTRL_SMC		(1 << 3)
 244#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 245#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
 246#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 247#define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
 248#define MX51_ECSPI_CTRL_BL_OFFSET	20
 249
 250#define MX51_ECSPI_CONFIG	0x0c
 251#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
 252#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
 253#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
 254#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
 255#define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
 256
 257#define MX51_ECSPI_INT		0x10
 258#define MX51_ECSPI_INT_TEEN		(1 <<  0)
 259#define MX51_ECSPI_INT_RREN		(1 <<  3)
 260
 261#define MX51_ECSPI_DMA      0x14
 262#define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
 263#define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
 264#define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
 265
 266#define MX51_ECSPI_DMA_TEDEN		(1 << 7)
 267#define MX51_ECSPI_DMA_RXDEN		(1 << 23)
 268#define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
 269
 270#define MX51_ECSPI_STAT		0x18
 271#define MX51_ECSPI_STAT_RR		(1 <<  3)
 272
 273#define MX51_ECSPI_TESTREG	0x20
 274#define MX51_ECSPI_TESTREG_LBC	BIT(31)
 275
 276/* MX51 eCSPI */
 277static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 278				      unsigned int fspi, unsigned int *fres)
 279{
 280	/*
 281	 * there are two 4-bit dividers, the pre-divider divides by
 282	 * $pre, the post-divider by 2^$post
 283	 */
 284	unsigned int pre, post;
 285	unsigned int fin = spi_imx->spi_clk;
 286
 287	if (unlikely(fspi > fin))
 288		return 0;
 289
 290	post = fls(fin) - fls(fspi);
 291	if (fin > fspi << post)
 292		post++;
 293
 294	/* now we have: (fin <= fspi << post) with post being minimal */
 295
 296	post = max(4U, post) - 4;
 297	if (unlikely(post > 0xf)) {
 298		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 299				fspi, fin);
 300		return 0xff;
 301	}
 302
 303	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 304
 305	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 306			__func__, fin, fspi, post, pre);
 307
 308	/* Resulting frequency for the SCLK line. */
 309	*fres = (fin / (pre + 1)) >> post;
 310
 311	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 312		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 313}
 314
 315static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 316{
 317	unsigned val = 0;
 318
 319	if (enable & MXC_INT_TE)
 320		val |= MX51_ECSPI_INT_TEEN;
 321
 322	if (enable & MXC_INT_RR)
 323		val |= MX51_ECSPI_INT_RREN;
 324
 325	writel(val, spi_imx->base + MX51_ECSPI_INT);
 326}
 327
 328static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 329{
 330	u32 reg;
 331
 332	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 333	reg |= MX51_ECSPI_CTRL_XCH;
 334	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 335}
 336
 337static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
 338		struct spi_imx_config *config)
 339{
 
 340	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 341	u32 clk = config->speed_hz, delay, reg;
 342	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 343
 344	/*
 345	 * The hardware seems to have a race condition when changing modes. The
 346	 * current assumption is that the selection of the channel arrives
 347	 * earlier in the hardware than the mode bits when they are written at
 348	 * the same time.
 349	 * So set master mode for all channels as we do not support slave mode.
 350	 */
 351	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 352
 353	/* set clock speed */
 354	ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk);
 355	spi_imx->spi_bus_clk = clk;
 356
 357	/* set chip select to use */
 358	ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
 359
 360	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
 361
 362	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
 363
 364	if (config->mode & SPI_CPHA)
 365		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
 366	else
 367		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
 368
 369	if (config->mode & SPI_CPOL) {
 370		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
 371		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
 372	} else {
 373		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
 374		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
 375	}
 376	if (config->mode & SPI_CS_HIGH)
 377		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
 378	else
 379		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(config->cs);
 380
 381	if (spi_imx->usedma)
 382		ctrl |= MX51_ECSPI_CTRL_SMC;
 383
 384	/* CTRL register always go first to bring out controller from reset */
 385	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 386
 387	reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 388	if (config->mode & SPI_LOOP)
 389		reg |= MX51_ECSPI_TESTREG_LBC;
 390	else
 391		reg &= ~MX51_ECSPI_TESTREG_LBC;
 392	writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
 393
 394	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 395
 396	/*
 397	 * Wait until the changes in the configuration register CONFIGREG
 398	 * propagate into the hardware. It takes exactly one tick of the
 399	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 400	 * effect of the delay it takes for the hardware to apply changes
 401	 * is noticable if the SCLK clock run very slow. In such a case, if
 402	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 403	 * be asserted before the SCLK polarity changes, which would disrupt
 404	 * the SPI communication as the device on the other end would consider
 405	 * the change of SCLK polarity as a clock tick already.
 406	 */
 407	delay = (2 * 1000000) / clk;
 408	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
 409		udelay(delay);
 410	else			/* SCLK is _very_ slow */
 411		usleep_range(delay, delay + 10);
 412
 413	/*
 414	 * Configure the DMA register: setup the watermark
 415	 * and enable DMA request.
 416	 */
 417
 418	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
 419		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 420		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 421		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 422		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 423
 424	return 0;
 425}
 426
 427static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 428{
 429	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 430}
 431
 432static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 433{
 434	/* drain receive buffer */
 435	while (mx51_ecspi_rx_available(spi_imx))
 436		readl(spi_imx->base + MXC_CSPIRXDATA);
 437}
 438
 439#define MX31_INTREG_TEEN	(1 << 0)
 440#define MX31_INTREG_RREN	(1 << 3)
 441
 442#define MX31_CSPICTRL_ENABLE	(1 << 0)
 443#define MX31_CSPICTRL_MASTER	(1 << 1)
 444#define MX31_CSPICTRL_XCH	(1 << 2)
 
 445#define MX31_CSPICTRL_POL	(1 << 4)
 446#define MX31_CSPICTRL_PHA	(1 << 5)
 447#define MX31_CSPICTRL_SSCTL	(1 << 6)
 448#define MX31_CSPICTRL_SSPOL	(1 << 7)
 449#define MX31_CSPICTRL_BC_SHIFT	8
 450#define MX35_CSPICTRL_BL_SHIFT	20
 451#define MX31_CSPICTRL_CS_SHIFT	24
 452#define MX35_CSPICTRL_CS_SHIFT	12
 453#define MX31_CSPICTRL_DR_SHIFT	16
 454
 
 
 
 
 455#define MX31_CSPISTATUS		0x14
 456#define MX31_STATUS_RR		(1 << 3)
 457
 
 
 
 458/* These functions also work for the i.MX35, but be aware that
 459 * the i.MX35 has a slightly different register layout for bits
 460 * we do not use here.
 461 */
 462static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 463{
 464	unsigned int val = 0;
 465
 466	if (enable & MXC_INT_TE)
 467		val |= MX31_INTREG_TEEN;
 468	if (enable & MXC_INT_RR)
 469		val |= MX31_INTREG_RREN;
 470
 471	writel(val, spi_imx->base + MXC_CSPIINT);
 472}
 473
 474static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
 475{
 476	unsigned int reg;
 477
 478	reg = readl(spi_imx->base + MXC_CSPICTRL);
 479	reg |= MX31_CSPICTRL_XCH;
 480	writel(reg, spi_imx->base + MXC_CSPICTRL);
 481}
 482
 483static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
 484		struct spi_imx_config *config)
 485{
 
 486	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 487	int cs = spi_imx->chipselect[config->cs];
 488
 489	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 490		MX31_CSPICTRL_DR_SHIFT;
 
 491
 492	if (is_imx35_cspi(spi_imx)) {
 493		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
 494		reg |= MX31_CSPICTRL_SSCTL;
 495	} else {
 496		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
 497	}
 498
 499	if (config->mode & SPI_CPHA)
 500		reg |= MX31_CSPICTRL_PHA;
 501	if (config->mode & SPI_CPOL)
 502		reg |= MX31_CSPICTRL_POL;
 503	if (config->mode & SPI_CS_HIGH)
 504		reg |= MX31_CSPICTRL_SSPOL;
 505	if (cs < 0)
 506		reg |= (cs + 32) <<
 507			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 508						  MX31_CSPICTRL_CS_SHIFT);
 509
 
 
 
 510	writel(reg, spi_imx->base + MXC_CSPICTRL);
 511
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 512	return 0;
 513}
 514
 515static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
 516{
 517	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 518}
 519
 520static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
 521{
 522	/* drain receive buffer */
 523	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 524		readl(spi_imx->base + MXC_CSPIRXDATA);
 525}
 526
 527#define MX21_INTREG_RR		(1 << 4)
 528#define MX21_INTREG_TEEN	(1 << 9)
 529#define MX21_INTREG_RREN	(1 << 13)
 530
 531#define MX21_CSPICTRL_POL	(1 << 5)
 532#define MX21_CSPICTRL_PHA	(1 << 6)
 533#define MX21_CSPICTRL_SSPOL	(1 << 8)
 534#define MX21_CSPICTRL_XCH	(1 << 9)
 535#define MX21_CSPICTRL_ENABLE	(1 << 10)
 536#define MX21_CSPICTRL_MASTER	(1 << 11)
 537#define MX21_CSPICTRL_DR_SHIFT	14
 538#define MX21_CSPICTRL_CS_SHIFT	19
 539
 540static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 541{
 542	unsigned int val = 0;
 543
 544	if (enable & MXC_INT_TE)
 545		val |= MX21_INTREG_TEEN;
 546	if (enable & MXC_INT_RR)
 547		val |= MX21_INTREG_RREN;
 548
 549	writel(val, spi_imx->base + MXC_CSPIINT);
 550}
 551
 552static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
 553{
 554	unsigned int reg;
 555
 556	reg = readl(spi_imx->base + MXC_CSPICTRL);
 557	reg |= MX21_CSPICTRL_XCH;
 558	writel(reg, spi_imx->base + MXC_CSPICTRL);
 559}
 560
 561static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
 562		struct spi_imx_config *config)
 563{
 
 564	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 565	int cs = spi_imx->chipselect[config->cs];
 566	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 
 
 
 
 
 567
 568	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
 569		MX21_CSPICTRL_DR_SHIFT;
 570	reg |= config->bpw - 1;
 571
 572	if (config->mode & SPI_CPHA)
 573		reg |= MX21_CSPICTRL_PHA;
 574	if (config->mode & SPI_CPOL)
 575		reg |= MX21_CSPICTRL_POL;
 576	if (config->mode & SPI_CS_HIGH)
 577		reg |= MX21_CSPICTRL_SSPOL;
 578	if (cs < 0)
 579		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
 580
 581	writel(reg, spi_imx->base + MXC_CSPICTRL);
 582
 583	return 0;
 584}
 585
 586static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
 587{
 588	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 589}
 590
 591static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
 592{
 593	writel(1, spi_imx->base + MXC_RESET);
 594}
 595
 596#define MX1_INTREG_RR		(1 << 3)
 597#define MX1_INTREG_TEEN		(1 << 8)
 598#define MX1_INTREG_RREN		(1 << 11)
 599
 600#define MX1_CSPICTRL_POL	(1 << 4)
 601#define MX1_CSPICTRL_PHA	(1 << 5)
 602#define MX1_CSPICTRL_XCH	(1 << 8)
 603#define MX1_CSPICTRL_ENABLE	(1 << 9)
 604#define MX1_CSPICTRL_MASTER	(1 << 10)
 605#define MX1_CSPICTRL_DR_SHIFT	13
 606
 607static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 608{
 609	unsigned int val = 0;
 610
 611	if (enable & MXC_INT_TE)
 612		val |= MX1_INTREG_TEEN;
 613	if (enable & MXC_INT_RR)
 614		val |= MX1_INTREG_RREN;
 615
 616	writel(val, spi_imx->base + MXC_CSPIINT);
 617}
 618
 619static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
 620{
 621	unsigned int reg;
 622
 623	reg = readl(spi_imx->base + MXC_CSPICTRL);
 624	reg |= MX1_CSPICTRL_XCH;
 625	writel(reg, spi_imx->base + MXC_CSPICTRL);
 626}
 627
 628static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
 629		struct spi_imx_config *config)
 630{
 
 631	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 
 632
 633	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 634		MX1_CSPICTRL_DR_SHIFT;
 
 
 635	reg |= config->bpw - 1;
 636
 637	if (config->mode & SPI_CPHA)
 638		reg |= MX1_CSPICTRL_PHA;
 639	if (config->mode & SPI_CPOL)
 640		reg |= MX1_CSPICTRL_POL;
 641
 642	writel(reg, spi_imx->base + MXC_CSPICTRL);
 643
 644	return 0;
 645}
 646
 647static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
 648{
 649	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 650}
 651
 652static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
 653{
 654	writel(1, spi_imx->base + MXC_RESET);
 655}
 656
 657static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 658	.intctrl = mx1_intctrl,
 659	.config = mx1_config,
 660	.trigger = mx1_trigger,
 661	.rx_available = mx1_rx_available,
 662	.reset = mx1_reset,
 663	.devtype = IMX1_CSPI,
 664};
 665
 666static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 667	.intctrl = mx21_intctrl,
 668	.config = mx21_config,
 669	.trigger = mx21_trigger,
 670	.rx_available = mx21_rx_available,
 671	.reset = mx21_reset,
 672	.devtype = IMX21_CSPI,
 673};
 674
 675static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 676	/* i.mx27 cspi shares the functions with i.mx21 one */
 677	.intctrl = mx21_intctrl,
 678	.config = mx21_config,
 679	.trigger = mx21_trigger,
 680	.rx_available = mx21_rx_available,
 681	.reset = mx21_reset,
 682	.devtype = IMX27_CSPI,
 683};
 684
 685static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 686	.intctrl = mx31_intctrl,
 687	.config = mx31_config,
 688	.trigger = mx31_trigger,
 689	.rx_available = mx31_rx_available,
 690	.reset = mx31_reset,
 691	.devtype = IMX31_CSPI,
 692};
 693
 694static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 695	/* i.mx35 and later cspi shares the functions with i.mx31 one */
 696	.intctrl = mx31_intctrl,
 697	.config = mx31_config,
 698	.trigger = mx31_trigger,
 699	.rx_available = mx31_rx_available,
 700	.reset = mx31_reset,
 701	.devtype = IMX35_CSPI,
 702};
 703
 704static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 705	.intctrl = mx51_ecspi_intctrl,
 706	.config = mx51_ecspi_config,
 707	.trigger = mx51_ecspi_trigger,
 708	.rx_available = mx51_ecspi_rx_available,
 709	.reset = mx51_ecspi_reset,
 710	.devtype = IMX51_ECSPI,
 711};
 712
 713static const struct platform_device_id spi_imx_devtype[] = {
 714	{
 715		.name = "imx1-cspi",
 716		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
 717	}, {
 718		.name = "imx21-cspi",
 719		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
 720	}, {
 721		.name = "imx27-cspi",
 722		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
 723	}, {
 724		.name = "imx31-cspi",
 725		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
 726	}, {
 727		.name = "imx35-cspi",
 728		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
 729	}, {
 730		.name = "imx51-ecspi",
 731		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
 732	}, {
 733		/* sentinel */
 734	}
 735};
 736
 737static const struct of_device_id spi_imx_dt_ids[] = {
 738	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
 739	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
 740	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
 741	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
 742	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
 743	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
 744	{ /* sentinel */ }
 745};
 746MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
 747
 748static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 749{
 750	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 751	int gpio = spi_imx->chipselect[spi->chip_select];
 752	int active = is_active != BITBANG_CS_INACTIVE;
 753	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
 754
 755	if (!gpio_is_valid(gpio))
 756		return;
 757
 758	gpio_set_value(gpio, dev_is_lowactive ^ active);
 759}
 760
 761static void spi_imx_push(struct spi_imx_data *spi_imx)
 762{
 763	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
 764		if (!spi_imx->count)
 765			break;
 766		spi_imx->tx(spi_imx);
 767		spi_imx->txfifo++;
 768	}
 769
 770	spi_imx->devtype_data->trigger(spi_imx);
 771}
 772
 773static irqreturn_t spi_imx_isr(int irq, void *dev_id)
 774{
 775	struct spi_imx_data *spi_imx = dev_id;
 776
 777	while (spi_imx->devtype_data->rx_available(spi_imx)) {
 778		spi_imx->rx(spi_imx);
 779		spi_imx->txfifo--;
 780	}
 781
 782	if (spi_imx->count) {
 783		spi_imx_push(spi_imx);
 784		return IRQ_HANDLED;
 785	}
 786
 787	if (spi_imx->txfifo) {
 788		/* No data left to push, but still waiting for rx data,
 789		 * enable receive data available interrupt.
 790		 */
 791		spi_imx->devtype_data->intctrl(
 792				spi_imx, MXC_INT_RR);
 793		return IRQ_HANDLED;
 794	}
 795
 796	spi_imx->devtype_data->intctrl(spi_imx, 0);
 797	complete(&spi_imx->xfer_done);
 798
 799	return IRQ_HANDLED;
 800}
 801
 802static int spi_imx_dma_configure(struct spi_master *master,
 803				 int bytes_per_word)
 804{
 805	int ret;
 806	enum dma_slave_buswidth buswidth;
 807	struct dma_slave_config rx = {}, tx = {};
 808	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 809
 810	if (bytes_per_word == spi_imx->bytes_per_word)
 811		/* Same as last time */
 812		return 0;
 813
 814	switch (bytes_per_word) {
 815	case 4:
 816		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 817		break;
 818	case 2:
 819		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
 820		break;
 821	case 1:
 822		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
 823		break;
 824	default:
 825		return -EINVAL;
 826	}
 827
 828	tx.direction = DMA_MEM_TO_DEV;
 829	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
 830	tx.dst_addr_width = buswidth;
 831	tx.dst_maxburst = spi_imx->wml;
 832	ret = dmaengine_slave_config(master->dma_tx, &tx);
 833	if (ret) {
 834		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
 835		return ret;
 836	}
 837
 838	rx.direction = DMA_DEV_TO_MEM;
 839	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
 840	rx.src_addr_width = buswidth;
 841	rx.src_maxburst = spi_imx->wml;
 842	ret = dmaengine_slave_config(master->dma_rx, &rx);
 843	if (ret) {
 844		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
 845		return ret;
 846	}
 847
 848	spi_imx->bytes_per_word = bytes_per_word;
 849
 850	return 0;
 851}
 852
 853static int spi_imx_setupxfer(struct spi_device *spi,
 854				 struct spi_transfer *t)
 855{
 856	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 857	struct spi_imx_config config;
 858	int ret;
 859
 860	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
 861	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
 862	config.mode = spi->mode;
 863	config.cs = spi->chip_select;
 864
 865	if (!config.speed_hz)
 866		config.speed_hz = spi->max_speed_hz;
 867	if (!config.bpw)
 868		config.bpw = spi->bits_per_word;
 869
 870	/* Initialize the functions for transfer */
 871	if (config.bpw <= 8) {
 872		spi_imx->rx = spi_imx_buf_rx_u8;
 873		spi_imx->tx = spi_imx_buf_tx_u8;
 874	} else if (config.bpw <= 16) {
 875		spi_imx->rx = spi_imx_buf_rx_u16;
 876		spi_imx->tx = spi_imx_buf_tx_u16;
 877	} else {
 878		spi_imx->rx = spi_imx_buf_rx_u32;
 879		spi_imx->tx = spi_imx_buf_tx_u32;
 880	}
 881
 882	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
 883		spi_imx->usedma = 1;
 884	else
 885		spi_imx->usedma = 0;
 886
 887	if (spi_imx->usedma) {
 888		ret = spi_imx_dma_configure(spi->master,
 889					    spi_imx_bytes_per_word(config.bpw));
 890		if (ret)
 891			return ret;
 892	}
 893
 894	spi_imx->devtype_data->config(spi_imx, &config);
 895
 896	return 0;
 897}
 898
 899static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
 900{
 901	struct spi_master *master = spi_imx->bitbang.master;
 902
 903	if (master->dma_rx) {
 904		dma_release_channel(master->dma_rx);
 905		master->dma_rx = NULL;
 906	}
 907
 908	if (master->dma_tx) {
 909		dma_release_channel(master->dma_tx);
 910		master->dma_tx = NULL;
 911	}
 912}
 913
 914static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
 915			     struct spi_master *master)
 916{
 917	int ret;
 918
 919	/* use pio mode for i.mx6dl chip TKT238285 */
 920	if (of_machine_is_compatible("fsl,imx6dl"))
 921		return 0;
 922
 923	spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2;
 924
 925	/* Prepare for TX DMA: */
 926	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
 927	if (IS_ERR(master->dma_tx)) {
 928		ret = PTR_ERR(master->dma_tx);
 929		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
 930		master->dma_tx = NULL;
 931		goto err;
 932	}
 933
 934	/* Prepare for RX : */
 935	master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
 936	if (IS_ERR(master->dma_rx)) {
 937		ret = PTR_ERR(master->dma_rx);
 938		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
 939		master->dma_rx = NULL;
 940		goto err;
 941	}
 942
 943	spi_imx_dma_configure(master, 1);
 944
 945	init_completion(&spi_imx->dma_rx_completion);
 946	init_completion(&spi_imx->dma_tx_completion);
 947	master->can_dma = spi_imx_can_dma;
 948	master->max_dma_len = MAX_SDMA_BD_BYTES;
 949	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
 950					 SPI_MASTER_MUST_TX;
 951
 952	return 0;
 953err:
 954	spi_imx_sdma_exit(spi_imx);
 955	return ret;
 956}
 957
 958static void spi_imx_dma_rx_callback(void *cookie)
 959{
 960	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 961
 962	complete(&spi_imx->dma_rx_completion);
 963}
 964
 965static void spi_imx_dma_tx_callback(void *cookie)
 966{
 967	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 968
 969	complete(&spi_imx->dma_tx_completion);
 970}
 971
 972static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
 973{
 974	unsigned long timeout = 0;
 975
 976	/* Time with actual data transfer and CS change delay related to HW */
 977	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
 978
 979	/* Add extra second for scheduler related activities */
 980	timeout += 1;
 981
 982	/* Double calculated timeout */
 983	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
 984}
 985
 986static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
 987				struct spi_transfer *transfer)
 988{
 989	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
 990	unsigned long transfer_timeout;
 991	unsigned long timeout;
 992	struct spi_master *master = spi_imx->bitbang.master;
 993	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
 994
 995	/*
 996	 * The TX DMA setup starts the transfer, so make sure RX is configured
 997	 * before TX.
 998	 */
 999	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1000				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1001				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1002	if (!desc_rx)
1003		return -EINVAL;
1004
1005	desc_rx->callback = spi_imx_dma_rx_callback;
1006	desc_rx->callback_param = (void *)spi_imx;
1007	dmaengine_submit(desc_rx);
1008	reinit_completion(&spi_imx->dma_rx_completion);
1009	dma_async_issue_pending(master->dma_rx);
1010
1011	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1012				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1013				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1014	if (!desc_tx) {
1015		dmaengine_terminate_all(master->dma_tx);
1016		return -EINVAL;
1017	}
1018
1019	desc_tx->callback = spi_imx_dma_tx_callback;
1020	desc_tx->callback_param = (void *)spi_imx;
1021	dmaengine_submit(desc_tx);
1022	reinit_completion(&spi_imx->dma_tx_completion);
1023	dma_async_issue_pending(master->dma_tx);
1024
1025	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1026
1027	/* Wait SDMA to finish the data transfer.*/
1028	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1029						transfer_timeout);
1030	if (!timeout) {
1031		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1032		dmaengine_terminate_all(master->dma_tx);
1033		dmaengine_terminate_all(master->dma_rx);
1034		return -ETIMEDOUT;
1035	}
1036
1037	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1038					      transfer_timeout);
1039	if (!timeout) {
1040		dev_err(&master->dev, "I/O Error in DMA RX\n");
1041		spi_imx->devtype_data->reset(spi_imx);
1042		dmaengine_terminate_all(master->dma_rx);
1043		return -ETIMEDOUT;
1044	}
1045
1046	return transfer->len;
1047}
1048
1049static int spi_imx_pio_transfer(struct spi_device *spi,
1050				struct spi_transfer *transfer)
1051{
1052	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
 
1053
1054	spi_imx->tx_buf = transfer->tx_buf;
1055	spi_imx->rx_buf = transfer->rx_buf;
1056	spi_imx->count = transfer->len;
1057	spi_imx->txfifo = 0;
1058
1059	reinit_completion(&spi_imx->xfer_done);
1060
1061	spi_imx_push(spi_imx);
1062
1063	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1064
1065	wait_for_completion(&spi_imx->xfer_done);
 
 
 
 
 
 
 
 
1066
1067	return transfer->len;
1068}
1069
1070static int spi_imx_transfer(struct spi_device *spi,
1071				struct spi_transfer *transfer)
1072{
1073	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1074
1075	if (spi_imx->usedma)
1076		return spi_imx_dma_transfer(spi_imx, transfer);
1077	else
1078		return spi_imx_pio_transfer(spi, transfer);
1079}
1080
1081static int spi_imx_setup(struct spi_device *spi)
1082{
1083	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1084	int gpio = spi_imx->chipselect[spi->chip_select];
1085
1086	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1087		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1088
1089	if (gpio_is_valid(gpio))
1090		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
 
1091
1092	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1093
1094	return 0;
1095}
1096
1097static void spi_imx_cleanup(struct spi_device *spi)
1098{
1099}
1100
1101static int
1102spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1103{
1104	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1105	int ret;
1106
1107	ret = clk_enable(spi_imx->clk_per);
1108	if (ret)
1109		return ret;
1110
1111	ret = clk_enable(spi_imx->clk_ipg);
1112	if (ret) {
1113		clk_disable(spi_imx->clk_per);
1114		return ret;
1115	}
1116
1117	return 0;
1118}
1119
1120static int
1121spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1122{
1123	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1124
1125	clk_disable(spi_imx->clk_ipg);
1126	clk_disable(spi_imx->clk_per);
1127	return 0;
1128}
1129
1130static int spi_imx_probe(struct platform_device *pdev)
1131{
1132	struct device_node *np = pdev->dev.of_node;
1133	const struct of_device_id *of_id =
1134			of_match_device(spi_imx_dt_ids, &pdev->dev);
1135	struct spi_imx_master *mxc_platform_info =
1136			dev_get_platdata(&pdev->dev);
1137	struct spi_master *master;
1138	struct spi_imx_data *spi_imx;
1139	struct resource *res;
1140	int i, ret, num_cs, irq;
1141
1142	if (!np && !mxc_platform_info) {
1143		dev_err(&pdev->dev, "can't get the platform data\n");
1144		return -EINVAL;
1145	}
1146
1147	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
1148	if (ret < 0) {
1149		if (mxc_platform_info)
1150			num_cs = mxc_platform_info->num_chipselect;
1151		else
1152			return ret;
1153	}
1154
1155	master = spi_alloc_master(&pdev->dev,
1156			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
1157	if (!master)
1158		return -ENOMEM;
1159
1160	platform_set_drvdata(pdev, master);
1161
1162	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1163	master->bus_num = pdev->id;
1164	master->num_chipselect = num_cs;
1165
1166	spi_imx = spi_master_get_devdata(master);
1167	spi_imx->bitbang.master = master;
1168	spi_imx->dev = &pdev->dev;
1169
1170	spi_imx->devtype_data = of_id ? of_id->data :
1171		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1172
1173	for (i = 0; i < master->num_chipselect; i++) {
1174		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
1175		if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
1176			cs_gpio = mxc_platform_info->chipselect[i];
1177
1178		spi_imx->chipselect[i] = cs_gpio;
1179		if (!gpio_is_valid(cs_gpio))
1180			continue;
1181
1182		ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
1183					DRIVER_NAME);
1184		if (ret) {
1185			dev_err(&pdev->dev, "can't get cs gpios\n");
1186			goto out_master_put;
1187		}
1188	}
1189
1190	spi_imx->bitbang.chipselect = spi_imx_chipselect;
1191	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1192	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1193	spi_imx->bitbang.master->setup = spi_imx_setup;
1194	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1195	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1196	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1197	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1198	if (is_imx51_ecspi(spi_imx))
1199		spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
1200
1201	init_completion(&spi_imx->xfer_done);
1202
1203	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1204	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1205	if (IS_ERR(spi_imx->base)) {
1206		ret = PTR_ERR(spi_imx->base);
1207		goto out_master_put;
1208	}
1209	spi_imx->base_phys = res->start;
1210
1211	irq = platform_get_irq(pdev, 0);
1212	if (irq < 0) {
1213		ret = irq;
1214		goto out_master_put;
1215	}
1216
1217	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1218			       dev_name(&pdev->dev), spi_imx);
1219	if (ret) {
1220		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1221		goto out_master_put;
1222	}
1223
1224	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1225	if (IS_ERR(spi_imx->clk_ipg)) {
1226		ret = PTR_ERR(spi_imx->clk_ipg);
1227		goto out_master_put;
1228	}
1229
1230	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1231	if (IS_ERR(spi_imx->clk_per)) {
1232		ret = PTR_ERR(spi_imx->clk_per);
1233		goto out_master_put;
1234	}
1235
1236	ret = clk_prepare_enable(spi_imx->clk_per);
1237	if (ret)
1238		goto out_master_put;
1239
1240	ret = clk_prepare_enable(spi_imx->clk_ipg);
1241	if (ret)
1242		goto out_put_per;
1243
1244	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1245	/*
1246	 * Only validated on i.mx6 now, can remove the constrain if validated on
1247	 * other chips.
1248	 */
1249	if (is_imx51_ecspi(spi_imx)) {
1250		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1251		if (ret == -EPROBE_DEFER)
1252			goto out_clk_put;
1253
1254		if (ret < 0)
1255			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1256				ret);
1257	}
1258
1259	spi_imx->devtype_data->reset(spi_imx);
1260
1261	spi_imx->devtype_data->intctrl(spi_imx, 0);
1262
1263	master->dev.of_node = pdev->dev.of_node;
1264	ret = spi_bitbang_start(&spi_imx->bitbang);
1265	if (ret) {
1266		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1267		goto out_clk_put;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1268	}
1269
1270	dev_info(&pdev->dev, "probed\n");
1271
1272	clk_disable(spi_imx->clk_ipg);
1273	clk_disable(spi_imx->clk_per);
1274	return ret;
1275
1276out_clk_put:
1277	clk_disable_unprepare(spi_imx->clk_ipg);
1278out_put_per:
1279	clk_disable_unprepare(spi_imx->clk_per);
1280out_master_put:
1281	spi_master_put(master);
1282
1283	return ret;
1284}
1285
1286static int spi_imx_remove(struct platform_device *pdev)
1287{
1288	struct spi_master *master = platform_get_drvdata(pdev);
1289	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1290
1291	spi_bitbang_stop(&spi_imx->bitbang);
1292
1293	writel(0, spi_imx->base + MXC_CSPICTRL);
1294	clk_unprepare(spi_imx->clk_ipg);
1295	clk_unprepare(spi_imx->clk_per);
1296	spi_imx_sdma_exit(spi_imx);
1297	spi_master_put(master);
1298
1299	return 0;
1300}
1301
1302static struct platform_driver spi_imx_driver = {
1303	.driver = {
1304		   .name = DRIVER_NAME,
1305		   .of_match_table = spi_imx_dt_ids,
1306		   },
1307	.id_table = spi_imx_devtype,
1308	.probe = spi_imx_probe,
1309	.remove = spi_imx_remove,
1310};
1311module_platform_driver(spi_imx_driver);
1312
1313MODULE_DESCRIPTION("SPI Master Controller driver");
1314MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1315MODULE_LICENSE("GPL");
1316MODULE_ALIAS("platform:" DRIVER_NAME);
   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);