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v3.5.6
   1/*
   2 * OMAP2 McSPI controller driver
   3 *
   4 * Copyright (C) 2005, 2006 Nokia Corporation
   5 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   6 *		Juha Yrj�l� <juha.yrjola@nokia.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License as published by
  10 * the Free Software Foundation; either version 2 of the License, or
  11 * (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21 *
  22 */
  23
  24#include <linux/kernel.h>
  25#include <linux/init.h>
  26#include <linux/interrupt.h>
  27#include <linux/module.h>
  28#include <linux/device.h>
  29#include <linux/delay.h>
  30#include <linux/dma-mapping.h>
 
 
  31#include <linux/platform_device.h>
  32#include <linux/err.h>
  33#include <linux/clk.h>
  34#include <linux/io.h>
  35#include <linux/slab.h>
  36#include <linux/pm_runtime.h>
  37#include <linux/of.h>
  38#include <linux/of_device.h>
 
  39
  40#include <linux/spi/spi.h>
 
  41
  42#include <plat/dma.h>
  43#include <plat/clock.h>
  44#include <plat/mcspi.h>
  45
  46#define OMAP2_MCSPI_MAX_FREQ		48000000
 
 
 
  47#define SPI_AUTOSUSPEND_TIMEOUT		2000
  48
  49#define OMAP2_MCSPI_REVISION		0x00
  50#define OMAP2_MCSPI_SYSSTATUS		0x14
  51#define OMAP2_MCSPI_IRQSTATUS		0x18
  52#define OMAP2_MCSPI_IRQENABLE		0x1c
  53#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  54#define OMAP2_MCSPI_SYST		0x24
  55#define OMAP2_MCSPI_MODULCTRL		0x28
 
  56
  57/* per-channel banks, 0x14 bytes each, first is: */
  58#define OMAP2_MCSPI_CHCONF0		0x2c
  59#define OMAP2_MCSPI_CHSTAT0		0x30
  60#define OMAP2_MCSPI_CHCTRL0		0x34
  61#define OMAP2_MCSPI_TX0			0x38
  62#define OMAP2_MCSPI_RX0			0x3c
  63
  64/* per-register bitmasks: */
 
  65
  66#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  67#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  68#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  69
  70#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  71#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  72#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  73#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  74#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  75#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  76#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  77#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  78#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  79#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  80#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  81#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  82#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  83#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  84#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
 
 
 
  85
  86#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  87#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  88#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
 
  89
  90#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
 
  91
  92#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  93
  94/* We have 2 DMA channels per CS, one for RX and one for TX */
  95struct omap2_mcspi_dma {
  96	int dma_tx_channel;
  97	int dma_rx_channel;
  98
  99	int dma_tx_sync_dev;
 100	int dma_rx_sync_dev;
 101
 102	struct completion dma_tx_completion;
 103	struct completion dma_rx_completion;
 
 
 
 104};
 105
 106/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 107 * cache operations; better heuristics consider wordsize and bitrate.
 108 */
 109#define DMA_MIN_BYTES			160
 110
 111
 112/*
 113 * Used for context save and restore, structure members to be updated whenever
 114 * corresponding registers are modified.
 115 */
 116struct omap2_mcspi_regs {
 117	u32 modulctrl;
 118	u32 wakeupenable;
 119	struct list_head cs;
 120};
 121
 122struct omap2_mcspi {
 123	struct spi_master	*master;
 124	/* Virtual base address of the controller */
 125	void __iomem		*base;
 126	unsigned long		phys;
 127	/* SPI1 has 4 channels, while SPI2 has 2 */
 128	struct omap2_mcspi_dma	*dma_channels;
 129	struct device		*dev;
 130	struct omap2_mcspi_regs ctx;
 
 
 131};
 132
 133struct omap2_mcspi_cs {
 134	void __iomem		*base;
 135	unsigned long		phys;
 136	int			word_len;
 
 137	struct list_head	node;
 138	/* Context save and restore shadow register */
 139	u32			chconf0;
 140};
 141
 142#define MOD_REG_BIT(val, mask, set) do { \
 143	if (set) \
 144		val |= mask; \
 145	else \
 146		val &= ~mask; \
 147} while (0)
 148
 149static inline void mcspi_write_reg(struct spi_master *master,
 150		int idx, u32 val)
 151{
 152	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 153
 154	__raw_writel(val, mcspi->base + idx);
 155}
 156
 157static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 158{
 159	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 160
 161	return __raw_readl(mcspi->base + idx);
 162}
 163
 164static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 165		int idx, u32 val)
 166{
 167	struct omap2_mcspi_cs	*cs = spi->controller_state;
 168
 169	__raw_writel(val, cs->base +  idx);
 170}
 171
 172static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 173{
 174	struct omap2_mcspi_cs	*cs = spi->controller_state;
 175
 176	return __raw_readl(cs->base + idx);
 177}
 178
 179static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 180{
 181	struct omap2_mcspi_cs *cs = spi->controller_state;
 182
 183	return cs->chconf0;
 184}
 185
 186static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 187{
 188	struct omap2_mcspi_cs *cs = spi->controller_state;
 189
 190	cs->chconf0 = val;
 191	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 192	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 193}
 194
 
 
 
 
 
 
 
 
 
 
 195static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 196		int is_read, int enable)
 197{
 198	u32 l, rw;
 199
 200	l = mcspi_cached_chconf0(spi);
 201
 202	if (is_read) /* 1 is read, 0 write */
 203		rw = OMAP2_MCSPI_CHCONF_DMAR;
 204	else
 205		rw = OMAP2_MCSPI_CHCONF_DMAW;
 206
 207	MOD_REG_BIT(l, rw, enable);
 
 
 
 
 208	mcspi_write_chconf0(spi, l);
 209}
 210
 211static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 212{
 
 213	u32 l;
 214
 215	l = enable ? OMAP2_MCSPI_CHCTRL_EN : 0;
 216	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, l);
 
 
 
 
 
 217	/* Flash post-writes */
 218	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 219}
 220
 221static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 222{
 
 223	u32 l;
 224
 225	l = mcspi_cached_chconf0(spi);
 226	MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active);
 227	mcspi_write_chconf0(spi, l);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 228}
 229
 230static void omap2_mcspi_set_master_mode(struct spi_master *master)
 231{
 232	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 233	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 234	u32 l;
 235
 236	/*
 237	 * Setup when switching from (reset default) slave mode
 238	 * to single-channel master mode
 239	 */
 240	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 241	MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_STEST, 0);
 242	MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_MS, 0);
 243	MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1);
 244	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 245
 246	ctx->modulctrl = l;
 247}
 248
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 249static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 250{
 251	struct spi_master	*spi_cntrl = mcspi->master;
 252	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 253	struct omap2_mcspi_cs	*cs;
 254
 255	/* McSPI: context restore */
 256	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
 257	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
 258
 259	list_for_each_entry(cs, &ctx->cs, node)
 260		__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 261}
 262static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
 263{
 264	pm_runtime_mark_last_busy(mcspi->dev);
 265	pm_runtime_put_autosuspend(mcspi->dev);
 266}
 267
 268static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi)
 269{
 270	return pm_runtime_get_sync(mcspi->dev);
 
 
 
 
 
 
 
 
 
 
 
 
 271}
 272
 273static int omap2_prepare_transfer(struct spi_master *master)
 274{
 275	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 
 
 276
 277	pm_runtime_get_sync(mcspi->dev);
 278	return 0;
 
 
 279}
 280
 281static int omap2_unprepare_transfer(struct spi_master *master)
 282{
 283	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 
 
 284
 285	pm_runtime_mark_last_busy(mcspi->dev);
 286	pm_runtime_put_autosuspend(mcspi->dev);
 287	return 0;
 
 288}
 289
 290static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 
 
 291{
 292	unsigned long timeout;
 
 
 293
 294	timeout = jiffies + msecs_to_jiffies(1000);
 295	while (!(__raw_readl(reg) & bit)) {
 296		if (time_after(jiffies, timeout))
 297			return -1;
 298		cpu_relax();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 299	}
 300	return 0;
 
 
 301}
 302
 303static unsigned
 304omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 
 
 305{
 306	struct omap2_mcspi	*mcspi;
 307	struct omap2_mcspi_cs	*cs = spi->controller_state;
 308	struct omap2_mcspi_dma  *mcspi_dma;
 309	unsigned int		count, c;
 310	unsigned long		base, tx_reg, rx_reg;
 311	int			word_len, data_type, element_count;
 312	int			elements = 0;
 313	u32			l;
 314	u8			* rx;
 315	const u8		* tx;
 316	void __iomem		*chstat_reg;
 
 317
 318	mcspi = spi_master_get_devdata(spi->master);
 319	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 320	l = mcspi_cached_chconf0(spi);
 321
 322	chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 
 
 
 
 
 
 323
 324	count = xfer->len;
 325	c = count;
 326	word_len = cs->word_len;
 
 327
 328	base = cs->phys;
 329	tx_reg = base + OMAP2_MCSPI_TX0;
 330	rx_reg = base + OMAP2_MCSPI_RX0;
 331	rx = xfer->rx_buf;
 332	tx = xfer->tx_buf;
 333
 334	if (word_len <= 8) {
 335		data_type = OMAP_DMA_DATA_TYPE_S8;
 336		element_count = count;
 337	} else if (word_len <= 16) {
 338		data_type = OMAP_DMA_DATA_TYPE_S16;
 339		element_count = count >> 1;
 340	} else /* word_len <= 32 */ {
 341		data_type = OMAP_DMA_DATA_TYPE_S32;
 342		element_count = count >> 2;
 343	}
 344
 345	if (tx != NULL) {
 346		omap_set_dma_transfer_params(mcspi_dma->dma_tx_channel,
 347				data_type, element_count, 1,
 348				OMAP_DMA_SYNC_ELEMENT,
 349				mcspi_dma->dma_tx_sync_dev, 0);
 350
 351		omap_set_dma_dest_params(mcspi_dma->dma_tx_channel, 0,
 352				OMAP_DMA_AMODE_CONSTANT,
 353				tx_reg, 0, 0);
 354
 355		omap_set_dma_src_params(mcspi_dma->dma_tx_channel, 0,
 356				OMAP_DMA_AMODE_POST_INC,
 357				xfer->tx_dma, 0, 0);
 358	}
 359
 360	if (rx != NULL) {
 361		elements = element_count - 1;
 362		if (l & OMAP2_MCSPI_CHCONF_TURBO)
 363			elements--;
 364
 365		omap_set_dma_transfer_params(mcspi_dma->dma_rx_channel,
 366				data_type, elements, 1,
 367				OMAP_DMA_SYNC_ELEMENT,
 368				mcspi_dma->dma_rx_sync_dev, 1);
 369
 370		omap_set_dma_src_params(mcspi_dma->dma_rx_channel, 0,
 371				OMAP_DMA_AMODE_CONSTANT,
 372				rx_reg, 0, 0);
 373
 374		omap_set_dma_dest_params(mcspi_dma->dma_rx_channel, 0,
 375				OMAP_DMA_AMODE_POST_INC,
 376				xfer->rx_dma, 0, 0);
 377	}
 378
 379	if (tx != NULL) {
 380		omap_start_dma(mcspi_dma->dma_tx_channel);
 381		omap2_mcspi_set_dma_req(spi, 0, 1);
 382	}
 383
 384	if (rx != NULL) {
 385		omap_start_dma(mcspi_dma->dma_rx_channel);
 386		omap2_mcspi_set_dma_req(spi, 1, 1);
 387	}
 
 
 388
 389	if (tx != NULL) {
 390		wait_for_completion(&mcspi_dma->dma_tx_completion);
 391		dma_unmap_single(&spi->dev, xfer->tx_dma, count, DMA_TO_DEVICE);
 
 
 
 
 
 
 
 
 
 
 392
 393		/* for TX_ONLY mode, be sure all words have shifted out */
 394		if (rx == NULL) {
 395			if (mcspi_wait_for_reg_bit(chstat_reg,
 396						OMAP2_MCSPI_CHSTAT_TXS) < 0)
 397				dev_err(&spi->dev, "TXS timed out\n");
 398			else if (mcspi_wait_for_reg_bit(chstat_reg,
 399						OMAP2_MCSPI_CHSTAT_EOT) < 0)
 400				dev_err(&spi->dev, "EOT timed out\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 401		}
 402	}
 403
 404	if (rx != NULL) {
 405		wait_for_completion(&mcspi_dma->dma_rx_completion);
 406		dma_unmap_single(&spi->dev, xfer->rx_dma, count, DMA_FROM_DEVICE);
 407		omap2_mcspi_set_enable(spi, 0);
 408
 409		if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 410
 411			if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 412				   & OMAP2_MCSPI_CHSTAT_RXS)) {
 413				u32 w;
 414
 415				w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 416				if (word_len <= 8)
 417					((u8 *)xfer->rx_buf)[elements++] = w;
 418				else if (word_len <= 16)
 419					((u16 *)xfer->rx_buf)[elements++] = w;
 420				else /* word_len <= 32 */
 421					((u32 *)xfer->rx_buf)[elements++] = w;
 422			} else {
 423				dev_err(&spi->dev,
 424					"DMA RX penultimate word empty");
 425				count -= (word_len <= 8)  ? 2 :
 426					(word_len <= 16) ? 4 :
 427					/* word_len <= 32 */ 8;
 428				omap2_mcspi_set_enable(spi, 1);
 429				return count;
 430			}
 431		}
 432
 433		if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 434				& OMAP2_MCSPI_CHSTAT_RXS)) {
 
 
 
 435			u32 w;
 436
 437			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 438			if (word_len <= 8)
 439				((u8 *)xfer->rx_buf)[elements] = w;
 440			else if (word_len <= 16)
 441				((u16 *)xfer->rx_buf)[elements] = w;
 442			else /* word_len <= 32 */
 443				((u32 *)xfer->rx_buf)[elements] = w;
 444		} else {
 445			dev_err(&spi->dev, "DMA RX last word empty");
 446			count -= (word_len <= 8)  ? 1 :
 447				 (word_len <= 16) ? 2 :
 448			       /* word_len <= 32 */ 4;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 449		}
 450		omap2_mcspi_set_enable(spi, 1);
 451	}
 452	return count;
 453}
 454
 455static unsigned
 456omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 457{
 458	struct omap2_mcspi	*mcspi;
 459	struct omap2_mcspi_cs	*cs = spi->controller_state;
 460	unsigned int		count, c;
 461	u32			l;
 462	void __iomem		*base = cs->base;
 463	void __iomem		*tx_reg;
 464	void __iomem		*rx_reg;
 465	void __iomem		*chstat_reg;
 466	int			word_len;
 467
 468	mcspi = spi_master_get_devdata(spi->master);
 469	count = xfer->len;
 470	c = count;
 471	word_len = cs->word_len;
 472
 473	l = mcspi_cached_chconf0(spi);
 474
 475	/* We store the pre-calculated register addresses on stack to speed
 476	 * up the transfer loop. */
 477	tx_reg		= base + OMAP2_MCSPI_TX0;
 478	rx_reg		= base + OMAP2_MCSPI_RX0;
 479	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 480
 481	if (c < (word_len>>3))
 482		return 0;
 483
 484	if (word_len <= 8) {
 485		u8		*rx;
 486		const u8	*tx;
 487
 488		rx = xfer->rx_buf;
 489		tx = xfer->tx_buf;
 490
 491		do {
 492			c -= 1;
 493			if (tx != NULL) {
 494				if (mcspi_wait_for_reg_bit(chstat_reg,
 495						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 496					dev_err(&spi->dev, "TXS timed out\n");
 497					goto out;
 498				}
 499				dev_vdbg(&spi->dev, "write-%d %02x\n",
 500						word_len, *tx);
 501				__raw_writel(*tx++, tx_reg);
 502			}
 503			if (rx != NULL) {
 504				if (mcspi_wait_for_reg_bit(chstat_reg,
 505						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 506					dev_err(&spi->dev, "RXS timed out\n");
 507					goto out;
 508				}
 509
 510				if (c == 1 && tx == NULL &&
 511				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 512					omap2_mcspi_set_enable(spi, 0);
 513					*rx++ = __raw_readl(rx_reg);
 514					dev_vdbg(&spi->dev, "read-%d %02x\n",
 515						    word_len, *(rx - 1));
 516					if (mcspi_wait_for_reg_bit(chstat_reg,
 517						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 518						dev_err(&spi->dev,
 519							"RXS timed out\n");
 520						goto out;
 521					}
 522					c = 0;
 523				} else if (c == 0 && tx == NULL) {
 524					omap2_mcspi_set_enable(spi, 0);
 525				}
 526
 527				*rx++ = __raw_readl(rx_reg);
 528				dev_vdbg(&spi->dev, "read-%d %02x\n",
 529						word_len, *(rx - 1));
 530			}
 531		} while (c);
 532	} else if (word_len <= 16) {
 533		u16		*rx;
 534		const u16	*tx;
 535
 536		rx = xfer->rx_buf;
 537		tx = xfer->tx_buf;
 538		do {
 539			c -= 2;
 540			if (tx != NULL) {
 541				if (mcspi_wait_for_reg_bit(chstat_reg,
 542						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 543					dev_err(&spi->dev, "TXS timed out\n");
 544					goto out;
 545				}
 546				dev_vdbg(&spi->dev, "write-%d %04x\n",
 547						word_len, *tx);
 548				__raw_writel(*tx++, tx_reg);
 549			}
 550			if (rx != NULL) {
 551				if (mcspi_wait_for_reg_bit(chstat_reg,
 552						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 553					dev_err(&spi->dev, "RXS timed out\n");
 554					goto out;
 555				}
 556
 557				if (c == 2 && tx == NULL &&
 558				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 559					omap2_mcspi_set_enable(spi, 0);
 560					*rx++ = __raw_readl(rx_reg);
 561					dev_vdbg(&spi->dev, "read-%d %04x\n",
 562						    word_len, *(rx - 1));
 563					if (mcspi_wait_for_reg_bit(chstat_reg,
 564						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 565						dev_err(&spi->dev,
 566							"RXS timed out\n");
 567						goto out;
 568					}
 569					c = 0;
 570				} else if (c == 0 && tx == NULL) {
 571					omap2_mcspi_set_enable(spi, 0);
 572				}
 573
 574				*rx++ = __raw_readl(rx_reg);
 575				dev_vdbg(&spi->dev, "read-%d %04x\n",
 576						word_len, *(rx - 1));
 577			}
 578		} while (c >= 2);
 579	} else if (word_len <= 32) {
 580		u32		*rx;
 581		const u32	*tx;
 582
 583		rx = xfer->rx_buf;
 584		tx = xfer->tx_buf;
 585		do {
 586			c -= 4;
 587			if (tx != NULL) {
 588				if (mcspi_wait_for_reg_bit(chstat_reg,
 589						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 590					dev_err(&spi->dev, "TXS timed out\n");
 591					goto out;
 592				}
 593				dev_vdbg(&spi->dev, "write-%d %08x\n",
 594						word_len, *tx);
 595				__raw_writel(*tx++, tx_reg);
 596			}
 597			if (rx != NULL) {
 598				if (mcspi_wait_for_reg_bit(chstat_reg,
 599						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 600					dev_err(&spi->dev, "RXS timed out\n");
 601					goto out;
 602				}
 603
 604				if (c == 4 && tx == NULL &&
 605				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 606					omap2_mcspi_set_enable(spi, 0);
 607					*rx++ = __raw_readl(rx_reg);
 608					dev_vdbg(&spi->dev, "read-%d %08x\n",
 609						    word_len, *(rx - 1));
 610					if (mcspi_wait_for_reg_bit(chstat_reg,
 611						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 612						dev_err(&spi->dev,
 613							"RXS timed out\n");
 614						goto out;
 615					}
 616					c = 0;
 617				} else if (c == 0 && tx == NULL) {
 618					omap2_mcspi_set_enable(spi, 0);
 619				}
 620
 621				*rx++ = __raw_readl(rx_reg);
 622				dev_vdbg(&spi->dev, "read-%d %08x\n",
 623						word_len, *(rx - 1));
 624			}
 625		} while (c >= 4);
 626	}
 627
 628	/* for TX_ONLY mode, be sure all words have shifted out */
 629	if (xfer->rx_buf == NULL) {
 630		if (mcspi_wait_for_reg_bit(chstat_reg,
 631				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 632			dev_err(&spi->dev, "TXS timed out\n");
 633		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 634				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 635			dev_err(&spi->dev, "EOT timed out\n");
 636
 637		/* disable chan to purge rx datas received in TX_ONLY transfer,
 638		 * otherwise these rx datas will affect the direct following
 639		 * RX_ONLY transfer.
 640		 */
 641		omap2_mcspi_set_enable(spi, 0);
 642	}
 643out:
 644	omap2_mcspi_set_enable(spi, 1);
 645	return count - c;
 646}
 647
 648static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 649{
 650	u32 div;
 651
 652	for (div = 0; div < 15; div++)
 653		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 654			return div;
 655
 656	return 15;
 657}
 658
 659/* called only when no transfer is active to this device */
 660static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 661		struct spi_transfer *t)
 662{
 663	struct omap2_mcspi_cs *cs = spi->controller_state;
 664	struct omap2_mcspi *mcspi;
 665	struct spi_master *spi_cntrl;
 666	u32 l = 0, div = 0;
 667	u8 word_len = spi->bits_per_word;
 668	u32 speed_hz = spi->max_speed_hz;
 669
 670	mcspi = spi_master_get_devdata(spi->master);
 671	spi_cntrl = mcspi->master;
 672
 673	if (t != NULL && t->bits_per_word)
 674		word_len = t->bits_per_word;
 675
 676	cs->word_len = word_len;
 677
 678	if (t && t->speed_hz)
 679		speed_hz = t->speed_hz;
 680
 681	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 682	div = omap2_mcspi_calc_divisor(speed_hz);
 
 
 
 
 
 
 
 
 
 
 683
 684	l = mcspi_cached_chconf0(spi);
 685
 686	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 687	 * REVISIT: this controller could support SPI_3WIRE mode.
 688	 */
 689	l &= ~(OMAP2_MCSPI_CHCONF_IS|OMAP2_MCSPI_CHCONF_DPE1);
 690	l |= OMAP2_MCSPI_CHCONF_DPE0;
 
 
 
 
 
 
 
 691
 692	/* wordlength */
 693	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 694	l |= (word_len - 1) << 7;
 695
 696	/* set chipselect polarity; manage with FORCE */
 697	if (!(spi->mode & SPI_CS_HIGH))
 698		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 699	else
 700		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 701
 702	/* set clock divisor */
 703	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 704	l |= div << 2;
 
 
 
 
 
 
 
 
 
 705
 706	/* set SPI mode 0..3 */
 707	if (spi->mode & SPI_CPOL)
 708		l |= OMAP2_MCSPI_CHCONF_POL;
 709	else
 710		l &= ~OMAP2_MCSPI_CHCONF_POL;
 711	if (spi->mode & SPI_CPHA)
 712		l |= OMAP2_MCSPI_CHCONF_PHA;
 713	else
 714		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 715
 716	mcspi_write_chconf0(spi, l);
 717
 
 
 718	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 719			OMAP2_MCSPI_MAX_FREQ >> div,
 720			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 721			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 722
 723	return 0;
 724}
 725
 726static void omap2_mcspi_dma_rx_callback(int lch, u16 ch_status, void *data)
 727{
 728	struct spi_device	*spi = data;
 729	struct omap2_mcspi	*mcspi;
 730	struct omap2_mcspi_dma	*mcspi_dma;
 731
 732	mcspi = spi_master_get_devdata(spi->master);
 733	mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
 734
 735	complete(&mcspi_dma->dma_rx_completion);
 736
 737	/* We must disable the DMA RX request */
 738	omap2_mcspi_set_dma_req(spi, 1, 0);
 739}
 740
 741static void omap2_mcspi_dma_tx_callback(int lch, u16 ch_status, void *data)
 742{
 743	struct spi_device	*spi = data;
 744	struct omap2_mcspi	*mcspi;
 745	struct omap2_mcspi_dma	*mcspi_dma;
 746
 747	mcspi = spi_master_get_devdata(spi->master);
 748	mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
 749
 750	complete(&mcspi_dma->dma_tx_completion);
 751
 752	/* We must disable the DMA TX request */
 753	omap2_mcspi_set_dma_req(spi, 0, 0);
 754}
 755
 756static int omap2_mcspi_request_dma(struct spi_device *spi)
 757{
 758	struct spi_master	*master = spi->master;
 759	struct omap2_mcspi	*mcspi;
 760	struct omap2_mcspi_dma	*mcspi_dma;
 
 761
 762	mcspi = spi_master_get_devdata(master);
 763	mcspi_dma = mcspi->dma_channels + spi->chip_select;
 764
 765	if (omap_request_dma(mcspi_dma->dma_rx_sync_dev, "McSPI RX",
 766			omap2_mcspi_dma_rx_callback, spi,
 767			&mcspi_dma->dma_rx_channel)) {
 768		dev_err(&spi->dev, "no RX DMA channel for McSPI\n");
 769		return -EAGAIN;
 770	}
 771
 772	if (omap_request_dma(mcspi_dma->dma_tx_sync_dev, "McSPI TX",
 773			omap2_mcspi_dma_tx_callback, spi,
 774			&mcspi_dma->dma_tx_channel)) {
 775		omap_free_dma(mcspi_dma->dma_rx_channel);
 776		mcspi_dma->dma_rx_channel = -1;
 777		dev_err(&spi->dev, "no TX DMA channel for McSPI\n");
 778		return -EAGAIN;
 779	}
 780
 781	init_completion(&mcspi_dma->dma_rx_completion);
 782	init_completion(&mcspi_dma->dma_tx_completion);
 783
 784	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 785}
 786
 787static int omap2_mcspi_setup(struct spi_device *spi)
 788{
 789	int			ret;
 790	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
 791	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 792	struct omap2_mcspi_dma	*mcspi_dma;
 793	struct omap2_mcspi_cs	*cs = spi->controller_state;
 794
 795	if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
 796		dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
 797			spi->bits_per_word);
 798		return -EINVAL;
 799	}
 800
 801	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 802
 803	if (!cs) {
 804		cs = kzalloc(sizeof *cs, GFP_KERNEL);
 805		if (!cs)
 806			return -ENOMEM;
 807		cs->base = mcspi->base + spi->chip_select * 0x14;
 808		cs->phys = mcspi->phys + spi->chip_select * 0x14;
 
 809		cs->chconf0 = 0;
 
 810		spi->controller_state = cs;
 811		/* Link this to context save list */
 812		list_add_tail(&cs->node, &ctx->cs);
 
 
 
 
 
 
 
 
 
 
 813	}
 814
 815	if (mcspi_dma->dma_rx_channel == -1
 816			|| mcspi_dma->dma_tx_channel == -1) {
 817		ret = omap2_mcspi_request_dma(spi);
 818		if (ret < 0)
 819			return ret;
 
 820	}
 821
 822	ret = omap2_mcspi_enable_clocks(mcspi);
 823	if (ret < 0)
 824		return ret;
 825
 826	ret = omap2_mcspi_setup_transfer(spi, NULL);
 827	omap2_mcspi_disable_clocks(mcspi);
 
 828
 829	return ret;
 830}
 831
 832static void omap2_mcspi_cleanup(struct spi_device *spi)
 833{
 834	struct omap2_mcspi	*mcspi;
 835	struct omap2_mcspi_dma	*mcspi_dma;
 836	struct omap2_mcspi_cs	*cs;
 837
 838	mcspi = spi_master_get_devdata(spi->master);
 839
 840	if (spi->controller_state) {
 841		/* Unlink controller state from context save list */
 842		cs = spi->controller_state;
 843		list_del(&cs->node);
 844
 845		kfree(cs);
 846	}
 847
 848	if (spi->chip_select < spi->master->num_chipselect) {
 849		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 850
 851		if (mcspi_dma->dma_rx_channel != -1) {
 852			omap_free_dma(mcspi_dma->dma_rx_channel);
 853			mcspi_dma->dma_rx_channel = -1;
 854		}
 855		if (mcspi_dma->dma_tx_channel != -1) {
 856			omap_free_dma(mcspi_dma->dma_tx_channel);
 857			mcspi_dma->dma_tx_channel = -1;
 858		}
 859	}
 
 
 
 860}
 861
 862static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
 
 
 863{
 864
 865	/* We only enable one channel at a time -- the one whose message is
 866	 * -- although this controller would gladly
 867	 * arbitrate among multiple channels.  This corresponds to "single
 868	 * channel" master mode.  As a side effect, we need to manage the
 869	 * chipselect with the FORCE bit ... CS != channel enable.
 870	 */
 871
 872	struct spi_device		*spi;
 873	struct spi_transfer		*t = NULL;
 874	int				cs_active = 0;
 875	struct omap2_mcspi_cs		*cs;
 876	struct omap2_mcspi_device_config *cd;
 877	int				par_override = 0;
 878	int				status = 0;
 879	u32				chconf;
 880
 881	spi = m->spi;
 
 882	cs = spi->controller_state;
 883	cd = spi->controller_data;
 884
 885	omap2_mcspi_set_enable(spi, 1);
 886	list_for_each_entry(t, &m->transfers, transfer_list) {
 887		if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
 888			status = -EINVAL;
 889			break;
 890		}
 891		if (par_override || t->speed_hz || t->bits_per_word) {
 892			par_override = 1;
 893			status = omap2_mcspi_setup_transfer(spi, t);
 894			if (status < 0)
 895				break;
 896			if (!t->speed_hz && !t->bits_per_word)
 897				par_override = 0;
 898		}
 899
 900		if (!cs_active) {
 901			omap2_mcspi_force_cs(spi, 1);
 902			cs_active = 1;
 903		}
 904
 905		chconf = mcspi_cached_chconf0(spi);
 906		chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
 907		chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
 908
 909		if (t->tx_buf == NULL)
 910			chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
 911		else if (t->rx_buf == NULL)
 912			chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
 913
 914		if (cd && cd->turbo_mode && t->tx_buf == NULL) {
 915			/* Turbo mode is for more than one word */
 916			if (t->len > ((cs->word_len + 7) >> 3))
 917				chconf |= OMAP2_MCSPI_CHCONF_TURBO;
 918		}
 919
 920		mcspi_write_chconf0(spi, chconf);
 
 921
 922		if (t->len) {
 923			unsigned	count;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 924
 925			/* RX_ONLY mode needs dummy data in TX reg */
 926			if (t->tx_buf == NULL)
 927				__raw_writel(0, cs->base
 928						+ OMAP2_MCSPI_TX0);
 929
 930			if (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)
 931				count = omap2_mcspi_txrx_dma(spi, t);
 932			else
 933				count = omap2_mcspi_txrx_pio(spi, t);
 934			m->actual_length += count;
 935
 936			if (count != t->len) {
 937				status = -EIO;
 938				break;
 939			}
 
 
 
 
 
 
 940		}
 
 
 
 941
 942		if (t->delay_usecs)
 943			udelay(t->delay_usecs);
 944
 945		/* ignore the "leave it on after last xfer" hint */
 946		if (t->cs_change) {
 947			omap2_mcspi_force_cs(spi, 0);
 948			cs_active = 0;
 949		}
 950	}
 951	/* Restore defaults if they were overriden */
 952	if (par_override) {
 953		par_override = 0;
 954		status = omap2_mcspi_setup_transfer(spi, NULL);
 955	}
 956
 957	if (cs_active)
 958		omap2_mcspi_force_cs(spi, 0);
 
 
 
 
 
 959
 960	omap2_mcspi_set_enable(spi, 0);
 961
 962	m->status = status;
 
 963
 
 
 
 
 964}
 965
 966static int omap2_mcspi_transfer_one_message(struct spi_master *master,
 967						struct spi_message *m)
 968{
 969	struct omap2_mcspi	*mcspi;
 970	struct spi_transfer	*t;
 971
 972	mcspi = spi_master_get_devdata(master);
 973	m->actual_length = 0;
 974	m->status = 0;
 975
 976	/* reject invalid messages and transfers */
 977	if (list_empty(&m->transfers))
 978		return -EINVAL;
 979	list_for_each_entry(t, &m->transfers, transfer_list) {
 980		const void	*tx_buf = t->tx_buf;
 981		void		*rx_buf = t->rx_buf;
 982		unsigned	len = t->len;
 983
 984		if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ
 985				|| (len && !(rx_buf || tx_buf))
 986				|| (t->bits_per_word &&
 987					(  t->bits_per_word < 4
 988					|| t->bits_per_word > 32))) {
 989			dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
 990					t->speed_hz,
 991					len,
 992					tx_buf ? "tx" : "",
 993					rx_buf ? "rx" : "",
 994					t->bits_per_word);
 995			return -EINVAL;
 996		}
 997		if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
 998			dev_dbg(mcspi->dev, "speed_hz %d below minimum %d Hz\n",
 999				t->speed_hz,
1000				OMAP2_MCSPI_MAX_FREQ >> 15);
1001			return -EINVAL;
1002		}
1003
1004		if (m->is_dma_mapped || len < DMA_MIN_BYTES)
 
 
 
 
 
 
1005			continue;
1006
1007		if (tx_buf != NULL) {
1008			t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1009					len, DMA_TO_DEVICE);
1010			if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1011				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1012						'T', len);
1013				return -EINVAL;
1014			}
1015		}
1016		if (rx_buf != NULL) {
1017			t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1018					DMA_FROM_DEVICE);
1019			if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1020				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1021						'R', len);
1022				if (tx_buf != NULL)
1023					dma_unmap_single(mcspi->dev, t->tx_dma,
1024							len, DMA_TO_DEVICE);
1025				return -EINVAL;
1026			}
1027		}
1028	}
1029
1030	omap2_mcspi_work(mcspi, m);
1031	spi_finalize_current_message(master);
1032	return 0;
1033}
1034
1035static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
 
 
 
 
 
 
 
1036{
1037	struct spi_master	*master = mcspi->master;
1038	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1039	int			ret = 0;
1040
1041	ret = omap2_mcspi_enable_clocks(mcspi);
1042	if (ret < 0)
1043		return ret;
1044
1045	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1046				OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1047	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1048
1049	omap2_mcspi_set_master_mode(master);
1050	omap2_mcspi_disable_clocks(mcspi);
 
1051	return 0;
1052}
1053
1054static int omap_mcspi_runtime_resume(struct device *dev)
1055{
1056	struct omap2_mcspi	*mcspi;
1057	struct spi_master	*master;
1058
1059	master = dev_get_drvdata(dev);
1060	mcspi = spi_master_get_devdata(master);
1061	omap2_mcspi_restore_ctx(mcspi);
1062
1063	return 0;
1064}
1065
1066static struct omap2_mcspi_platform_config omap2_pdata = {
1067	.regs_offset = 0,
1068};
1069
1070static struct omap2_mcspi_platform_config omap4_pdata = {
1071	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1072};
1073
1074static const struct of_device_id omap_mcspi_of_match[] = {
1075	{
1076		.compatible = "ti,omap2-mcspi",
1077		.data = &omap2_pdata,
1078	},
1079	{
1080		.compatible = "ti,omap4-mcspi",
1081		.data = &omap4_pdata,
1082	},
1083	{ },
1084};
1085MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1086
1087static int __devinit omap2_mcspi_probe(struct platform_device *pdev)
1088{
1089	struct spi_master	*master;
1090	struct omap2_mcspi_platform_config *pdata;
1091	struct omap2_mcspi	*mcspi;
1092	struct resource		*r;
1093	int			status = 0, i;
1094	u32			regs_offset = 0;
1095	static int		bus_num = 1;
1096	struct device_node	*node = pdev->dev.of_node;
1097	const struct of_device_id *match;
1098
1099	master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1100	if (master == NULL) {
1101		dev_dbg(&pdev->dev, "master allocation failed\n");
1102		return -ENOMEM;
1103	}
1104
1105	/* the spi->mode bits understood by this driver: */
1106	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1107
1108	master->setup = omap2_mcspi_setup;
1109	master->prepare_transfer_hardware = omap2_prepare_transfer;
1110	master->unprepare_transfer_hardware = omap2_unprepare_transfer;
1111	master->transfer_one_message = omap2_mcspi_transfer_one_message;
 
 
1112	master->cleanup = omap2_mcspi_cleanup;
1113	master->dev.of_node = node;
 
 
 
 
 
 
 
1114
1115	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1116	if (match) {
1117		u32 num_cs = 1; /* default number of chipselect */
1118		pdata = match->data;
1119
1120		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1121		master->num_chipselect = num_cs;
1122		master->bus_num = bus_num++;
 
1123	} else {
1124		pdata = pdev->dev.platform_data;
1125		master->num_chipselect = pdata->num_cs;
1126		if (pdev->id != -1)
1127			master->bus_num = pdev->id;
1128	}
1129	regs_offset = pdata->regs_offset;
1130
1131	dev_set_drvdata(&pdev->dev, master);
1132
1133	mcspi = spi_master_get_devdata(master);
1134	mcspi->master = master;
1135
1136	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1137	if (r == NULL) {
1138		status = -ENODEV;
1139		goto free_master;
1140	}
1141
1142	r->start += regs_offset;
1143	r->end += regs_offset;
1144	mcspi->phys = r->start;
1145
1146	mcspi->base = devm_request_and_ioremap(&pdev->dev, r);
1147	if (!mcspi->base) {
1148		dev_dbg(&pdev->dev, "can't ioremap MCSPI\n");
1149		status = -ENOMEM;
1150		goto free_master;
1151	}
 
 
1152
1153	mcspi->dev = &pdev->dev;
1154
1155	INIT_LIST_HEAD(&mcspi->ctx.cs);
1156
1157	mcspi->dma_channels = kcalloc(master->num_chipselect,
1158			sizeof(struct omap2_mcspi_dma),
1159			GFP_KERNEL);
1160
1161	if (mcspi->dma_channels == NULL)
1162		goto free_master;
 
1163
1164	for (i = 0; i < master->num_chipselect; i++) {
1165		char dma_ch_name[14];
1166		struct resource *dma_res;
1167
1168		sprintf(dma_ch_name, "rx%d", i);
1169		dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1170							dma_ch_name);
1171		if (!dma_res) {
1172			dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
1173			status = -ENODEV;
1174			break;
1175		}
1176
1177		mcspi->dma_channels[i].dma_rx_channel = -1;
1178		mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
1179		sprintf(dma_ch_name, "tx%d", i);
1180		dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1181							dma_ch_name);
1182		if (!dma_res) {
1183			dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
1184			status = -ENODEV;
1185			break;
1186		}
1187
1188		mcspi->dma_channels[i].dma_tx_channel = -1;
1189		mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start;
1190	}
1191
1192	if (status < 0)
1193		goto dma_chnl_free;
1194
1195	pm_runtime_use_autosuspend(&pdev->dev);
1196	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1197	pm_runtime_enable(&pdev->dev);
1198
1199	if (status || omap2_mcspi_master_setup(mcspi) < 0)
 
1200		goto disable_pm;
1201
1202	status = spi_register_master(master);
1203	if (status < 0)
1204		goto err_spi_register;
1205
1206	return status;
1207
1208err_spi_register:
1209	spi_master_put(master);
1210disable_pm:
 
 
1211	pm_runtime_disable(&pdev->dev);
1212dma_chnl_free:
1213	kfree(mcspi->dma_channels);
1214free_master:
1215	kfree(master);
1216	platform_set_drvdata(pdev, NULL);
1217	return status;
1218}
1219
1220static int __devexit omap2_mcspi_remove(struct platform_device *pdev)
1221{
1222	struct spi_master	*master;
1223	struct omap2_mcspi	*mcspi;
1224	struct omap2_mcspi_dma	*dma_channels;
1225
1226	master = dev_get_drvdata(&pdev->dev);
1227	mcspi = spi_master_get_devdata(master);
1228	dma_channels = mcspi->dma_channels;
1229
1230	omap2_mcspi_disable_clocks(mcspi);
 
1231	pm_runtime_disable(&pdev->dev);
1232
1233	spi_unregister_master(master);
1234	kfree(dma_channels);
1235	platform_set_drvdata(pdev, NULL);
1236
1237	return 0;
1238}
1239
1240/* work with hotplug and coldplug */
1241MODULE_ALIAS("platform:omap2_mcspi");
1242
1243#ifdef	CONFIG_SUSPEND
1244/*
1245 * When SPI wake up from off-mode, CS is in activate state. If it was in
1246 * unactive state when driver was suspend, then force it to unactive state at
1247 * wake up.
1248 */
1249static int omap2_mcspi_resume(struct device *dev)
1250{
1251	struct spi_master	*master = dev_get_drvdata(dev);
1252	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1253	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1254	struct omap2_mcspi_cs	*cs;
1255
1256	omap2_mcspi_enable_clocks(mcspi);
1257	list_for_each_entry(cs, &ctx->cs, node) {
1258		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1259			/*
1260			 * We need to toggle CS state for OMAP take this
1261			 * change in account.
1262			 */
1263			MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 1);
1264			__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1265			MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 0);
1266			__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1267		}
1268	}
1269	omap2_mcspi_disable_clocks(mcspi);
1270	return 0;
 
 
1271}
 
 
 
 
 
 
1272#else
 
1273#define	omap2_mcspi_resume	NULL
1274#endif
1275
1276static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1277	.resume = omap2_mcspi_resume,
 
1278	.runtime_resume	= omap_mcspi_runtime_resume,
1279};
1280
1281static struct platform_driver omap2_mcspi_driver = {
1282	.driver = {
1283		.name =		"omap2_mcspi",
1284		.owner =	THIS_MODULE,
1285		.pm =		&omap2_mcspi_pm_ops,
1286		.of_match_table = omap_mcspi_of_match,
1287	},
1288	.probe =	omap2_mcspi_probe,
1289	.remove =	__devexit_p(omap2_mcspi_remove),
1290};
1291
1292module_platform_driver(omap2_mcspi_driver);
1293MODULE_LICENSE("GPL");
v4.17
   1/*
   2 * OMAP2 McSPI controller driver
   3 *
   4 * Copyright (C) 2005, 2006 Nokia Corporation
   5 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   6 *		Juha Yrj�l� <juha.yrjola@nokia.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License as published by
  10 * the Free Software Foundation; either version 2 of the License, or
  11 * (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16 * GNU General Public License for more details.
 
 
 
 
 
  17 */
  18
  19#include <linux/kernel.h>
 
  20#include <linux/interrupt.h>
  21#include <linux/module.h>
  22#include <linux/device.h>
  23#include <linux/delay.h>
  24#include <linux/dma-mapping.h>
  25#include <linux/dmaengine.h>
  26#include <linux/pinctrl/consumer.h>
  27#include <linux/platform_device.h>
  28#include <linux/err.h>
  29#include <linux/clk.h>
  30#include <linux/io.h>
  31#include <linux/slab.h>
  32#include <linux/pm_runtime.h>
  33#include <linux/of.h>
  34#include <linux/of_device.h>
  35#include <linux/gcd.h>
  36
  37#include <linux/spi/spi.h>
  38#include <linux/gpio.h>
  39
  40#include <linux/platform_data/spi-omap2-mcspi.h>
 
 
  41
  42#define OMAP2_MCSPI_MAX_FREQ		48000000
  43#define OMAP2_MCSPI_MAX_DIVIDER		4096
  44#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  45#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  46#define SPI_AUTOSUSPEND_TIMEOUT		2000
  47
  48#define OMAP2_MCSPI_REVISION		0x00
  49#define OMAP2_MCSPI_SYSSTATUS		0x14
  50#define OMAP2_MCSPI_IRQSTATUS		0x18
  51#define OMAP2_MCSPI_IRQENABLE		0x1c
  52#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  53#define OMAP2_MCSPI_SYST		0x24
  54#define OMAP2_MCSPI_MODULCTRL		0x28
  55#define OMAP2_MCSPI_XFERLEVEL		0x7c
  56
  57/* per-channel banks, 0x14 bytes each, first is: */
  58#define OMAP2_MCSPI_CHCONF0		0x2c
  59#define OMAP2_MCSPI_CHSTAT0		0x30
  60#define OMAP2_MCSPI_CHCTRL0		0x34
  61#define OMAP2_MCSPI_TX0			0x38
  62#define OMAP2_MCSPI_RX0			0x3c
  63
  64/* per-register bitmasks: */
  65#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  66
  67#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  68#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  69#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  70
  71#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  72#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  73#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  74#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  75#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  76#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  77#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  78#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  79#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  80#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  81#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  82#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  83#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  84#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  85#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  86#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  87#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  88#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  89
  90#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  91#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  92#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  93#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  94
  95#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
  96#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
  97
  98#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  99
 100/* We have 2 DMA channels per CS, one for RX and one for TX */
 101struct omap2_mcspi_dma {
 102	struct dma_chan *dma_tx;
 103	struct dma_chan *dma_rx;
 
 
 
 104
 105	struct completion dma_tx_completion;
 106	struct completion dma_rx_completion;
 107
 108	char dma_rx_ch_name[14];
 109	char dma_tx_ch_name[14];
 110};
 111
 112/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 113 * cache operations; better heuristics consider wordsize and bitrate.
 114 */
 115#define DMA_MIN_BYTES			160
 116
 117
 118/*
 119 * Used for context save and restore, structure members to be updated whenever
 120 * corresponding registers are modified.
 121 */
 122struct omap2_mcspi_regs {
 123	u32 modulctrl;
 124	u32 wakeupenable;
 125	struct list_head cs;
 126};
 127
 128struct omap2_mcspi {
 129	struct spi_master	*master;
 130	/* Virtual base address of the controller */
 131	void __iomem		*base;
 132	unsigned long		phys;
 133	/* SPI1 has 4 channels, while SPI2 has 2 */
 134	struct omap2_mcspi_dma	*dma_channels;
 135	struct device		*dev;
 136	struct omap2_mcspi_regs ctx;
 137	int			fifo_depth;
 138	unsigned int		pin_dir:1;
 139};
 140
 141struct omap2_mcspi_cs {
 142	void __iomem		*base;
 143	unsigned long		phys;
 144	int			word_len;
 145	u16			mode;
 146	struct list_head	node;
 147	/* Context save and restore shadow register */
 148	u32			chconf0, chctrl0;
 149};
 150
 
 
 
 
 
 
 
 151static inline void mcspi_write_reg(struct spi_master *master,
 152		int idx, u32 val)
 153{
 154	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 155
 156	writel_relaxed(val, mcspi->base + idx);
 157}
 158
 159static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 160{
 161	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 162
 163	return readl_relaxed(mcspi->base + idx);
 164}
 165
 166static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 167		int idx, u32 val)
 168{
 169	struct omap2_mcspi_cs	*cs = spi->controller_state;
 170
 171	writel_relaxed(val, cs->base +  idx);
 172}
 173
 174static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 175{
 176	struct omap2_mcspi_cs	*cs = spi->controller_state;
 177
 178	return readl_relaxed(cs->base + idx);
 179}
 180
 181static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 182{
 183	struct omap2_mcspi_cs *cs = spi->controller_state;
 184
 185	return cs->chconf0;
 186}
 187
 188static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 189{
 190	struct omap2_mcspi_cs *cs = spi->controller_state;
 191
 192	cs->chconf0 = val;
 193	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 194	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 195}
 196
 197static inline int mcspi_bytes_per_word(int word_len)
 198{
 199	if (word_len <= 8)
 200		return 1;
 201	else if (word_len <= 16)
 202		return 2;
 203	else /* word_len <= 32 */
 204		return 4;
 205}
 206
 207static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 208		int is_read, int enable)
 209{
 210	u32 l, rw;
 211
 212	l = mcspi_cached_chconf0(spi);
 213
 214	if (is_read) /* 1 is read, 0 write */
 215		rw = OMAP2_MCSPI_CHCONF_DMAR;
 216	else
 217		rw = OMAP2_MCSPI_CHCONF_DMAW;
 218
 219	if (enable)
 220		l |= rw;
 221	else
 222		l &= ~rw;
 223
 224	mcspi_write_chconf0(spi, l);
 225}
 226
 227static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 228{
 229	struct omap2_mcspi_cs *cs = spi->controller_state;
 230	u32 l;
 231
 232	l = cs->chctrl0;
 233	if (enable)
 234		l |= OMAP2_MCSPI_CHCTRL_EN;
 235	else
 236		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 237	cs->chctrl0 = l;
 238	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 239	/* Flash post-writes */
 240	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 241}
 242
 243static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 244{
 245	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 246	u32 l;
 247
 248	/* The controller handles the inverted chip selects
 249	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 250	 * the inversion from the core spi_set_cs function.
 251	 */
 252	if (spi->mode & SPI_CS_HIGH)
 253		enable = !enable;
 254
 255	if (spi->controller_state) {
 256		int err = pm_runtime_get_sync(mcspi->dev);
 257		if (err < 0) {
 258			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 259			return;
 260		}
 261
 262		l = mcspi_cached_chconf0(spi);
 263
 264		if (enable)
 265			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 266		else
 267			l |= OMAP2_MCSPI_CHCONF_FORCE;
 268
 269		mcspi_write_chconf0(spi, l);
 270
 271		pm_runtime_mark_last_busy(mcspi->dev);
 272		pm_runtime_put_autosuspend(mcspi->dev);
 273	}
 274}
 275
 276static void omap2_mcspi_set_master_mode(struct spi_master *master)
 277{
 278	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 279	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 280	u32 l;
 281
 282	/*
 283	 * Setup when switching from (reset default) slave mode
 284	 * to single-channel master mode
 285	 */
 286	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 287	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
 288	l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 
 289	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 290
 291	ctx->modulctrl = l;
 292}
 293
 294static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 295				struct spi_transfer *t, int enable)
 296{
 297	struct spi_master *master = spi->master;
 298	struct omap2_mcspi_cs *cs = spi->controller_state;
 299	struct omap2_mcspi *mcspi;
 300	unsigned int wcnt;
 301	int max_fifo_depth, fifo_depth, bytes_per_word;
 302	u32 chconf, xferlevel;
 303
 304	mcspi = spi_master_get_devdata(master);
 305
 306	chconf = mcspi_cached_chconf0(spi);
 307	if (enable) {
 308		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 309		if (t->len % bytes_per_word != 0)
 310			goto disable_fifo;
 311
 312		if (t->rx_buf != NULL && t->tx_buf != NULL)
 313			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 314		else
 315			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 316
 317		fifo_depth = gcd(t->len, max_fifo_depth);
 318		if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
 319			goto disable_fifo;
 320
 321		wcnt = t->len / bytes_per_word;
 322		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 323			goto disable_fifo;
 324
 325		xferlevel = wcnt << 16;
 326		if (t->rx_buf != NULL) {
 327			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 328			xferlevel |= (fifo_depth - 1) << 8;
 329		}
 330		if (t->tx_buf != NULL) {
 331			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 332			xferlevel |= fifo_depth - 1;
 333		}
 334
 335		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 336		mcspi_write_chconf0(spi, chconf);
 337		mcspi->fifo_depth = fifo_depth;
 338
 339		return;
 340	}
 341
 342disable_fifo:
 343	if (t->rx_buf != NULL)
 344		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 345
 346	if (t->tx_buf != NULL)
 347		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 348
 349	mcspi_write_chconf0(spi, chconf);
 350	mcspi->fifo_depth = 0;
 351}
 352
 353static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 354{
 355	struct spi_master	*spi_cntrl = mcspi->master;
 356	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 357	struct omap2_mcspi_cs	*cs;
 358
 359	/* McSPI: context restore */
 360	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
 361	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
 362
 363	list_for_each_entry(cs, &ctx->cs, node)
 364		writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 
 
 
 
 
 365}
 366
 367static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 368{
 369	unsigned long timeout;
 370
 371	timeout = jiffies + msecs_to_jiffies(1000);
 372	while (!(readl_relaxed(reg) & bit)) {
 373		if (time_after(jiffies, timeout)) {
 374			if (!(readl_relaxed(reg) & bit))
 375				return -ETIMEDOUT;
 376			else
 377				return 0;
 378		}
 379		cpu_relax();
 380	}
 381	return 0;
 382}
 383
 384static void omap2_mcspi_rx_callback(void *data)
 385{
 386	struct spi_device *spi = data;
 387	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 388	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 389
 390	/* We must disable the DMA RX request */
 391	omap2_mcspi_set_dma_req(spi, 1, 0);
 392
 393	complete(&mcspi_dma->dma_rx_completion);
 394}
 395
 396static void omap2_mcspi_tx_callback(void *data)
 397{
 398	struct spi_device *spi = data;
 399	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 400	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 401
 402	/* We must disable the DMA TX request */
 403	omap2_mcspi_set_dma_req(spi, 0, 0);
 404
 405	complete(&mcspi_dma->dma_tx_completion);
 406}
 407
 408static void omap2_mcspi_tx_dma(struct spi_device *spi,
 409				struct spi_transfer *xfer,
 410				struct dma_slave_config cfg)
 411{
 412	struct omap2_mcspi	*mcspi;
 413	struct omap2_mcspi_dma  *mcspi_dma;
 414	unsigned int		count;
 415
 416	mcspi = spi_master_get_devdata(spi->master);
 417	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 418	count = xfer->len;
 419
 420	if (mcspi_dma->dma_tx) {
 421		struct dma_async_tx_descriptor *tx;
 422
 423		dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 424
 425		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 426					     xfer->tx_sg.nents,
 427					     DMA_MEM_TO_DEV,
 428					     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 429		if (tx) {
 430			tx->callback = omap2_mcspi_tx_callback;
 431			tx->callback_param = spi;
 432			dmaengine_submit(tx);
 433		} else {
 434			/* FIXME: fall back to PIO? */
 435		}
 436	}
 437	dma_async_issue_pending(mcspi_dma->dma_tx);
 438	omap2_mcspi_set_dma_req(spi, 0, 1);
 439
 440}
 441
 442static unsigned
 443omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 444				struct dma_slave_config cfg,
 445				unsigned es)
 446{
 447	struct omap2_mcspi	*mcspi;
 
 448	struct omap2_mcspi_dma  *mcspi_dma;
 449	unsigned int		count, transfer_reduction = 0;
 450	struct scatterlist	*sg_out[2];
 451	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 452	size_t			sizes[2];
 453	u32			l;
 454	int			elements = 0;
 455	int			word_len, element_count;
 456	struct omap2_mcspi_cs	*cs = spi->controller_state;
 457	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 458
 459	mcspi = spi_master_get_devdata(spi->master);
 460	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 461	count = xfer->len;
 462
 463	/*
 464	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 465	 *  it mentions reducing DMA transfer length by one element in master
 466	 *  normal mode.
 467	 */
 468	if (mcspi->fifo_depth == 0)
 469		transfer_reduction = es;
 470
 
 
 471	word_len = cs->word_len;
 472	l = mcspi_cached_chconf0(spi);
 473
 474	if (word_len <= 8)
 
 
 
 
 
 
 
 475		element_count = count;
 476	else if (word_len <= 16)
 
 477		element_count = count >> 1;
 478	else /* word_len <= 32 */
 
 479		element_count = count >> 2;
 
 480
 481	if (mcspi_dma->dma_rx) {
 482		struct dma_async_tx_descriptor *tx;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 483
 484		dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 
 
 
 485
 486		/*
 487		 *  Reduce DMA transfer length by one more if McSPI is
 488		 *  configured in turbo mode.
 489		 */
 490		if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 491			transfer_reduction += es;
 492
 493		if (transfer_reduction) {
 494			/* Split sgl into two. The second sgl won't be used. */
 495			sizes[0] = count - transfer_reduction;
 496			sizes[1] = transfer_reduction;
 497			nb_sizes = 2;
 498		} else {
 499			/*
 500			 * Don't bother splitting the sgl. This essentially
 501			 * clones the original sgl.
 502			 */
 503			sizes[0] = count;
 504			nb_sizes = 1;
 505		}
 506
 507		ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents,
 508			       0, nb_sizes,
 509			       sizes,
 510			       sg_out, out_mapped_nents,
 511			       GFP_KERNEL);
 512
 513		if (ret < 0) {
 514			dev_err(&spi->dev, "sg_split failed\n");
 515			return 0;
 516		}
 517
 518		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx,
 519					     sg_out[0],
 520					     out_mapped_nents[0],
 521					     DMA_DEV_TO_MEM,
 522					     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 523		if (tx) {
 524			tx->callback = omap2_mcspi_rx_callback;
 525			tx->callback_param = spi;
 526			dmaengine_submit(tx);
 527		} else {
 528				/* FIXME: fall back to PIO? */
 529		}
 530	}
 531
 532	dma_async_issue_pending(mcspi_dma->dma_rx);
 533	omap2_mcspi_set_dma_req(spi, 1, 1);
 
 
 534
 535	wait_for_completion(&mcspi_dma->dma_rx_completion);
 536
 537	for (x = 0; x < nb_sizes; x++)
 538		kfree(sg_out[x]);
 539
 540	if (mcspi->fifo_depth > 0)
 541		return count;
 542
 543	/*
 544	 *  Due to the DMA transfer length reduction the missing bytes must
 545	 *  be read manually to receive all of the expected data.
 546	 */
 547	omap2_mcspi_set_enable(spi, 0);
 548
 549	elements = element_count - 1;
 
 
 
 
 
 
 
 
 550
 551	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 552		elements--;
 553
 554		if (!mcspi_wait_for_reg_bit(chstat_reg,
 555					    OMAP2_MCSPI_CHSTAT_RXS)) {
 556			u32 w;
 557
 558			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 559			if (word_len <= 8)
 560				((u8 *)xfer->rx_buf)[elements++] = w;
 561			else if (word_len <= 16)
 562				((u16 *)xfer->rx_buf)[elements++] = w;
 563			else /* word_len <= 32 */
 564				((u32 *)xfer->rx_buf)[elements++] = w;
 565		} else {
 566			int bytes_per_word = mcspi_bytes_per_word(word_len);
 567			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 568			count -= (bytes_per_word << 1);
 569			omap2_mcspi_set_enable(spi, 1);
 570			return count;
 571		}
 572	}
 573	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 574		u32 w;
 575
 576		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 577		if (word_len <= 8)
 578			((u8 *)xfer->rx_buf)[elements] = w;
 579		else if (word_len <= 16)
 580			((u16 *)xfer->rx_buf)[elements] = w;
 581		else /* word_len <= 32 */
 582			((u32 *)xfer->rx_buf)[elements] = w;
 583	} else {
 584		dev_err(&spi->dev, "DMA RX last word empty\n");
 585		count -= mcspi_bytes_per_word(word_len);
 586	}
 587	omap2_mcspi_set_enable(spi, 1);
 588	return count;
 589}
 590
 591static unsigned
 592omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 593{
 594	struct omap2_mcspi	*mcspi;
 595	struct omap2_mcspi_cs	*cs = spi->controller_state;
 596	struct omap2_mcspi_dma  *mcspi_dma;
 597	unsigned int		count;
 598	u32			l;
 599	u8			*rx;
 600	const u8		*tx;
 601	struct dma_slave_config	cfg;
 602	enum dma_slave_buswidth width;
 603	unsigned es;
 604	u32			burst;
 605	void __iomem		*chstat_reg;
 606	void __iomem            *irqstat_reg;
 607	int			wait_res;
 608
 609	mcspi = spi_master_get_devdata(spi->master);
 610	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 611	l = mcspi_cached_chconf0(spi);
 612
 613
 614	if (cs->word_len <= 8) {
 615		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 616		es = 1;
 617	} else if (cs->word_len <= 16) {
 618		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 619		es = 2;
 620	} else {
 621		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 622		es = 4;
 623	}
 624
 625	count = xfer->len;
 626	burst = 1;
 627
 628	if (mcspi->fifo_depth > 0) {
 629		if (count > mcspi->fifo_depth)
 630			burst = mcspi->fifo_depth / es;
 631		else
 632			burst = count / es;
 633	}
 634
 635	memset(&cfg, 0, sizeof(cfg));
 636	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 637	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 638	cfg.src_addr_width = width;
 639	cfg.dst_addr_width = width;
 640	cfg.src_maxburst = burst;
 641	cfg.dst_maxburst = burst;
 642
 643	rx = xfer->rx_buf;
 644	tx = xfer->tx_buf;
 645
 646	if (tx != NULL)
 647		omap2_mcspi_tx_dma(spi, xfer, cfg);
 648
 649	if (rx != NULL)
 650		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 651
 652	if (tx != NULL) {
 653		wait_for_completion(&mcspi_dma->dma_tx_completion);
 654
 655		if (mcspi->fifo_depth > 0) {
 656			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 657
 658			if (mcspi_wait_for_reg_bit(irqstat_reg,
 659						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 660				dev_err(&spi->dev, "EOW timed out\n");
 661
 662			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 663					OMAP2_MCSPI_IRQSTATUS_EOW);
 664		}
 665
 666		/* for TX_ONLY mode, be sure all words have shifted out */
 667		if (rx == NULL) {
 668			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 669			if (mcspi->fifo_depth > 0) {
 670				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 671						OMAP2_MCSPI_CHSTAT_TXFFE);
 672				if (wait_res < 0)
 673					dev_err(&spi->dev, "TXFFE timed out\n");
 674			} else {
 675				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 676						OMAP2_MCSPI_CHSTAT_TXS);
 677				if (wait_res < 0)
 678					dev_err(&spi->dev, "TXS timed out\n");
 679			}
 680			if (wait_res >= 0 &&
 681				(mcspi_wait_for_reg_bit(chstat_reg,
 682					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 683				dev_err(&spi->dev, "EOT timed out\n");
 684		}
 
 685	}
 686	return count;
 687}
 688
 689static unsigned
 690omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 691{
 692	struct omap2_mcspi	*mcspi;
 693	struct omap2_mcspi_cs	*cs = spi->controller_state;
 694	unsigned int		count, c;
 695	u32			l;
 696	void __iomem		*base = cs->base;
 697	void __iomem		*tx_reg;
 698	void __iomem		*rx_reg;
 699	void __iomem		*chstat_reg;
 700	int			word_len;
 701
 702	mcspi = spi_master_get_devdata(spi->master);
 703	count = xfer->len;
 704	c = count;
 705	word_len = cs->word_len;
 706
 707	l = mcspi_cached_chconf0(spi);
 708
 709	/* We store the pre-calculated register addresses on stack to speed
 710	 * up the transfer loop. */
 711	tx_reg		= base + OMAP2_MCSPI_TX0;
 712	rx_reg		= base + OMAP2_MCSPI_RX0;
 713	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 714
 715	if (c < (word_len>>3))
 716		return 0;
 717
 718	if (word_len <= 8) {
 719		u8		*rx;
 720		const u8	*tx;
 721
 722		rx = xfer->rx_buf;
 723		tx = xfer->tx_buf;
 724
 725		do {
 726			c -= 1;
 727			if (tx != NULL) {
 728				if (mcspi_wait_for_reg_bit(chstat_reg,
 729						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 730					dev_err(&spi->dev, "TXS timed out\n");
 731					goto out;
 732				}
 733				dev_vdbg(&spi->dev, "write-%d %02x\n",
 734						word_len, *tx);
 735				writel_relaxed(*tx++, tx_reg);
 736			}
 737			if (rx != NULL) {
 738				if (mcspi_wait_for_reg_bit(chstat_reg,
 739						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 740					dev_err(&spi->dev, "RXS timed out\n");
 741					goto out;
 742				}
 743
 744				if (c == 1 && tx == NULL &&
 745				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 746					omap2_mcspi_set_enable(spi, 0);
 747					*rx++ = readl_relaxed(rx_reg);
 748					dev_vdbg(&spi->dev, "read-%d %02x\n",
 749						    word_len, *(rx - 1));
 750					if (mcspi_wait_for_reg_bit(chstat_reg,
 751						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 752						dev_err(&spi->dev,
 753							"RXS timed out\n");
 754						goto out;
 755					}
 756					c = 0;
 757				} else if (c == 0 && tx == NULL) {
 758					omap2_mcspi_set_enable(spi, 0);
 759				}
 760
 761				*rx++ = readl_relaxed(rx_reg);
 762				dev_vdbg(&spi->dev, "read-%d %02x\n",
 763						word_len, *(rx - 1));
 764			}
 765		} while (c);
 766	} else if (word_len <= 16) {
 767		u16		*rx;
 768		const u16	*tx;
 769
 770		rx = xfer->rx_buf;
 771		tx = xfer->tx_buf;
 772		do {
 773			c -= 2;
 774			if (tx != NULL) {
 775				if (mcspi_wait_for_reg_bit(chstat_reg,
 776						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 777					dev_err(&spi->dev, "TXS timed out\n");
 778					goto out;
 779				}
 780				dev_vdbg(&spi->dev, "write-%d %04x\n",
 781						word_len, *tx);
 782				writel_relaxed(*tx++, tx_reg);
 783			}
 784			if (rx != NULL) {
 785				if (mcspi_wait_for_reg_bit(chstat_reg,
 786						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 787					dev_err(&spi->dev, "RXS timed out\n");
 788					goto out;
 789				}
 790
 791				if (c == 2 && tx == NULL &&
 792				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 793					omap2_mcspi_set_enable(spi, 0);
 794					*rx++ = readl_relaxed(rx_reg);
 795					dev_vdbg(&spi->dev, "read-%d %04x\n",
 796						    word_len, *(rx - 1));
 797					if (mcspi_wait_for_reg_bit(chstat_reg,
 798						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 799						dev_err(&spi->dev,
 800							"RXS timed out\n");
 801						goto out;
 802					}
 803					c = 0;
 804				} else if (c == 0 && tx == NULL) {
 805					omap2_mcspi_set_enable(spi, 0);
 806				}
 807
 808				*rx++ = readl_relaxed(rx_reg);
 809				dev_vdbg(&spi->dev, "read-%d %04x\n",
 810						word_len, *(rx - 1));
 811			}
 812		} while (c >= 2);
 813	} else if (word_len <= 32) {
 814		u32		*rx;
 815		const u32	*tx;
 816
 817		rx = xfer->rx_buf;
 818		tx = xfer->tx_buf;
 819		do {
 820			c -= 4;
 821			if (tx != NULL) {
 822				if (mcspi_wait_for_reg_bit(chstat_reg,
 823						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 824					dev_err(&spi->dev, "TXS timed out\n");
 825					goto out;
 826				}
 827				dev_vdbg(&spi->dev, "write-%d %08x\n",
 828						word_len, *tx);
 829				writel_relaxed(*tx++, tx_reg);
 830			}
 831			if (rx != NULL) {
 832				if (mcspi_wait_for_reg_bit(chstat_reg,
 833						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 834					dev_err(&spi->dev, "RXS timed out\n");
 835					goto out;
 836				}
 837
 838				if (c == 4 && tx == NULL &&
 839				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 840					omap2_mcspi_set_enable(spi, 0);
 841					*rx++ = readl_relaxed(rx_reg);
 842					dev_vdbg(&spi->dev, "read-%d %08x\n",
 843						    word_len, *(rx - 1));
 844					if (mcspi_wait_for_reg_bit(chstat_reg,
 845						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 846						dev_err(&spi->dev,
 847							"RXS timed out\n");
 848						goto out;
 849					}
 850					c = 0;
 851				} else if (c == 0 && tx == NULL) {
 852					omap2_mcspi_set_enable(spi, 0);
 853				}
 854
 855				*rx++ = readl_relaxed(rx_reg);
 856				dev_vdbg(&spi->dev, "read-%d %08x\n",
 857						word_len, *(rx - 1));
 858			}
 859		} while (c >= 4);
 860	}
 861
 862	/* for TX_ONLY mode, be sure all words have shifted out */
 863	if (xfer->rx_buf == NULL) {
 864		if (mcspi_wait_for_reg_bit(chstat_reg,
 865				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 866			dev_err(&spi->dev, "TXS timed out\n");
 867		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 868				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 869			dev_err(&spi->dev, "EOT timed out\n");
 870
 871		/* disable chan to purge rx datas received in TX_ONLY transfer,
 872		 * otherwise these rx datas will affect the direct following
 873		 * RX_ONLY transfer.
 874		 */
 875		omap2_mcspi_set_enable(spi, 0);
 876	}
 877out:
 878	omap2_mcspi_set_enable(spi, 1);
 879	return count - c;
 880}
 881
 882static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 883{
 884	u32 div;
 885
 886	for (div = 0; div < 15; div++)
 887		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 888			return div;
 889
 890	return 15;
 891}
 892
 893/* called only when no transfer is active to this device */
 894static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 895		struct spi_transfer *t)
 896{
 897	struct omap2_mcspi_cs *cs = spi->controller_state;
 898	struct omap2_mcspi *mcspi;
 899	struct spi_master *spi_cntrl;
 900	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 901	u8 word_len = spi->bits_per_word;
 902	u32 speed_hz = spi->max_speed_hz;
 903
 904	mcspi = spi_master_get_devdata(spi->master);
 905	spi_cntrl = mcspi->master;
 906
 907	if (t != NULL && t->bits_per_word)
 908		word_len = t->bits_per_word;
 909
 910	cs->word_len = word_len;
 911
 912	if (t && t->speed_hz)
 913		speed_hz = t->speed_hz;
 914
 915	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 916	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 917		clkd = omap2_mcspi_calc_divisor(speed_hz);
 918		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 919		clkg = 0;
 920	} else {
 921		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 922		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 923		clkd = (div - 1) & 0xf;
 924		extclk = (div - 1) >> 4;
 925		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 926	}
 927
 928	l = mcspi_cached_chconf0(spi);
 929
 930	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 931	 * REVISIT: this controller could support SPI_3WIRE mode.
 932	 */
 933	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 934		l &= ~OMAP2_MCSPI_CHCONF_IS;
 935		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 936		l |= OMAP2_MCSPI_CHCONF_DPE0;
 937	} else {
 938		l |= OMAP2_MCSPI_CHCONF_IS;
 939		l |= OMAP2_MCSPI_CHCONF_DPE1;
 940		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 941	}
 942
 943	/* wordlength */
 944	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 945	l |= (word_len - 1) << 7;
 946
 947	/* set chipselect polarity; manage with FORCE */
 948	if (!(spi->mode & SPI_CS_HIGH))
 949		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 950	else
 951		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 952
 953	/* set clock divisor */
 954	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 955	l |= clkd << 2;
 956
 957	/* set clock granularity */
 958	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 959	l |= clkg;
 960	if (clkg) {
 961		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 962		cs->chctrl0 |= extclk << 8;
 963		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 964	}
 965
 966	/* set SPI mode 0..3 */
 967	if (spi->mode & SPI_CPOL)
 968		l |= OMAP2_MCSPI_CHCONF_POL;
 969	else
 970		l &= ~OMAP2_MCSPI_CHCONF_POL;
 971	if (spi->mode & SPI_CPHA)
 972		l |= OMAP2_MCSPI_CHCONF_PHA;
 973	else
 974		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 975
 976	mcspi_write_chconf0(spi, l);
 977
 978	cs->mode = spi->mode;
 979
 980	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 981			speed_hz,
 982			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 983			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 984
 985	return 0;
 986}
 987
 988/*
 989 * Note that we currently allow DMA only if we get a channel
 990 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 991 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 992static int omap2_mcspi_request_dma(struct spi_device *spi)
 993{
 994	struct spi_master	*master = spi->master;
 995	struct omap2_mcspi	*mcspi;
 996	struct omap2_mcspi_dma	*mcspi_dma;
 997	int ret = 0;
 998
 999	mcspi = spi_master_get_devdata(master);
1000	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1001
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1002	init_completion(&mcspi_dma->dma_rx_completion);
1003	init_completion(&mcspi_dma->dma_tx_completion);
1004
1005	mcspi_dma->dma_rx = dma_request_chan(&master->dev,
1006					     mcspi_dma->dma_rx_ch_name);
1007	if (IS_ERR(mcspi_dma->dma_rx)) {
1008		ret = PTR_ERR(mcspi_dma->dma_rx);
1009		mcspi_dma->dma_rx = NULL;
1010		goto no_dma;
1011	}
1012
1013	mcspi_dma->dma_tx = dma_request_chan(&master->dev,
1014					     mcspi_dma->dma_tx_ch_name);
1015	if (IS_ERR(mcspi_dma->dma_tx)) {
1016		ret = PTR_ERR(mcspi_dma->dma_tx);
1017		mcspi_dma->dma_tx = NULL;
1018		dma_release_channel(mcspi_dma->dma_rx);
1019		mcspi_dma->dma_rx = NULL;
1020	}
1021
1022no_dma:
1023	return ret;
1024}
1025
1026static int omap2_mcspi_setup(struct spi_device *spi)
1027{
1028	int			ret;
1029	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
1030	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1031	struct omap2_mcspi_dma	*mcspi_dma;
1032	struct omap2_mcspi_cs	*cs = spi->controller_state;
1033
 
 
 
 
 
 
1034	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1035
1036	if (!cs) {
1037		cs = kzalloc(sizeof *cs, GFP_KERNEL);
1038		if (!cs)
1039			return -ENOMEM;
1040		cs->base = mcspi->base + spi->chip_select * 0x14;
1041		cs->phys = mcspi->phys + spi->chip_select * 0x14;
1042		cs->mode = 0;
1043		cs->chconf0 = 0;
1044		cs->chctrl0 = 0;
1045		spi->controller_state = cs;
1046		/* Link this to context save list */
1047		list_add_tail(&cs->node, &ctx->cs);
1048
1049		if (gpio_is_valid(spi->cs_gpio)) {
1050			ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1051			if (ret) {
1052				dev_err(&spi->dev, "failed to request gpio\n");
1053				return ret;
1054			}
1055			gpio_direction_output(spi->cs_gpio,
1056					 !(spi->mode & SPI_CS_HIGH));
1057		}
1058	}
1059
1060	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
 
1061		ret = omap2_mcspi_request_dma(spi);
1062		if (ret)
1063			dev_warn(&spi->dev, "not using DMA for McSPI (%d)\n",
1064				 ret);
1065	}
1066
1067	ret = pm_runtime_get_sync(mcspi->dev);
1068	if (ret < 0)
1069		return ret;
1070
1071	ret = omap2_mcspi_setup_transfer(spi, NULL);
1072	pm_runtime_mark_last_busy(mcspi->dev);
1073	pm_runtime_put_autosuspend(mcspi->dev);
1074
1075	return ret;
1076}
1077
1078static void omap2_mcspi_cleanup(struct spi_device *spi)
1079{
1080	struct omap2_mcspi	*mcspi;
1081	struct omap2_mcspi_dma	*mcspi_dma;
1082	struct omap2_mcspi_cs	*cs;
1083
1084	mcspi = spi_master_get_devdata(spi->master);
1085
1086	if (spi->controller_state) {
1087		/* Unlink controller state from context save list */
1088		cs = spi->controller_state;
1089		list_del(&cs->node);
1090
1091		kfree(cs);
1092	}
1093
1094	if (spi->chip_select < spi->master->num_chipselect) {
1095		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1096
1097		if (mcspi_dma->dma_rx) {
1098			dma_release_channel(mcspi_dma->dma_rx);
1099			mcspi_dma->dma_rx = NULL;
1100		}
1101		if (mcspi_dma->dma_tx) {
1102			dma_release_channel(mcspi_dma->dma_tx);
1103			mcspi_dma->dma_tx = NULL;
1104		}
1105	}
1106
1107	if (gpio_is_valid(spi->cs_gpio))
1108		gpio_free(spi->cs_gpio);
1109}
1110
1111static int omap2_mcspi_transfer_one(struct spi_master *master,
1112				    struct spi_device *spi,
1113				    struct spi_transfer *t)
1114{
1115
1116	/* We only enable one channel at a time -- the one whose message is
1117	 * -- although this controller would gladly
1118	 * arbitrate among multiple channels.  This corresponds to "single
1119	 * channel" master mode.  As a side effect, we need to manage the
1120	 * chipselect with the FORCE bit ... CS != channel enable.
1121	 */
1122
1123	struct omap2_mcspi		*mcspi;
1124	struct omap2_mcspi_dma		*mcspi_dma;
 
1125	struct omap2_mcspi_cs		*cs;
1126	struct omap2_mcspi_device_config *cd;
1127	int				par_override = 0;
1128	int				status = 0;
1129	u32				chconf;
1130
1131	mcspi = spi_master_get_devdata(master);
1132	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1133	cs = spi->controller_state;
1134	cd = spi->controller_data;
1135
1136	/*
1137	 * The slave driver could have changed spi->mode in which case
1138	 * it will be different from cs->mode (the current hardware setup).
1139	 * If so, set par_override (even though its not a parity issue) so
1140	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1141	 * with the correct mode on the first iteration of the loop below.
1142	 */
1143	if (spi->mode != cs->mode)
1144		par_override = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1145
1146	omap2_mcspi_set_enable(spi, 0);
 
 
 
 
 
 
 
 
 
1147
1148	if (gpio_is_valid(spi->cs_gpio))
1149		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1150
1151	if (par_override ||
1152	    (t->speed_hz != spi->max_speed_hz) ||
1153	    (t->bits_per_word != spi->bits_per_word)) {
1154		par_override = 1;
1155		status = omap2_mcspi_setup_transfer(spi, t);
1156		if (status < 0)
1157			goto out;
1158		if (t->speed_hz == spi->max_speed_hz &&
1159		    t->bits_per_word == spi->bits_per_word)
1160			par_override = 0;
1161	}
1162	if (cd && cd->cs_per_word) {
1163		chconf = mcspi->ctx.modulctrl;
1164		chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1165		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1166		mcspi->ctx.modulctrl =
1167			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1168	}
1169
1170	chconf = mcspi_cached_chconf0(spi);
1171	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1172	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1173
1174	if (t->tx_buf == NULL)
1175		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1176	else if (t->rx_buf == NULL)
1177		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1178
1179	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1180		/* Turbo mode is for more than one word */
1181		if (t->len > ((cs->word_len + 7) >> 3))
1182			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1183	}
1184
1185	mcspi_write_chconf0(spi, chconf);
1186
1187	if (t->len) {
1188		unsigned	count;
1189
1190		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1191		    master->cur_msg_mapped &&
1192		    master->can_dma(master, spi, t))
1193			omap2_mcspi_set_fifo(spi, t, 1);
1194
1195		omap2_mcspi_set_enable(spi, 1);
 
 
 
1196
1197		/* RX_ONLY mode needs dummy data in TX reg */
1198		if (t->tx_buf == NULL)
1199			writel_relaxed(0, cs->base
1200					+ OMAP2_MCSPI_TX0);
 
1201
1202		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1203		    master->cur_msg_mapped &&
1204		    master->can_dma(master, spi, t))
1205			count = omap2_mcspi_txrx_dma(spi, t);
1206		else
1207			count = omap2_mcspi_txrx_pio(spi, t);
1208
1209		if (count != t->len) {
1210			status = -EIO;
1211			goto out;
1212		}
1213	}
1214
1215	omap2_mcspi_set_enable(spi, 0);
1216
1217	if (mcspi->fifo_depth > 0)
1218		omap2_mcspi_set_fifo(spi, t, 0);
1219
1220out:
 
 
 
 
 
1221	/* Restore defaults if they were overriden */
1222	if (par_override) {
1223		par_override = 0;
1224		status = omap2_mcspi_setup_transfer(spi, NULL);
1225	}
1226
1227	if (cd && cd->cs_per_word) {
1228		chconf = mcspi->ctx.modulctrl;
1229		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1230		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1231		mcspi->ctx.modulctrl =
1232			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1233	}
1234
1235	omap2_mcspi_set_enable(spi, 0);
1236
1237	if (gpio_is_valid(spi->cs_gpio))
1238		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1239
1240	if (mcspi->fifo_depth > 0 && t)
1241		omap2_mcspi_set_fifo(spi, t, 0);
1242
1243	return status;
1244}
1245
1246static int omap2_mcspi_prepare_message(struct spi_master *master,
1247				       struct spi_message *msg)
1248{
1249	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1250	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1251	struct omap2_mcspi_cs	*cs;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1252
1253	/* Only a single channel can have the FORCE bit enabled
1254	 * in its chconf0 register.
1255	 * Scan all channels and disable them except the current one.
1256	 * A FORCE can remain from a last transfer having cs_change enabled
1257	 */
1258	list_for_each_entry(cs, &ctx->cs, node) {
1259		if (msg->spi->controller_state == cs)
1260			continue;
1261
1262		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1263			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1264			writel_relaxed(cs->chconf0,
1265					cs->base + OMAP2_MCSPI_CHCONF0);
1266			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1267		}
1268	}
1269
 
 
1270	return 0;
1271}
1272
1273static bool omap2_mcspi_can_dma(struct spi_master *master,
1274				struct spi_device *spi,
1275				struct spi_transfer *xfer)
1276{
1277	return (xfer->len >= DMA_MIN_BYTES);
1278}
1279
1280static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1281{
1282	struct spi_master	*master = mcspi->master;
1283	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1284	int			ret = 0;
1285
1286	ret = pm_runtime_get_sync(mcspi->dev);
1287	if (ret < 0)
1288		return ret;
1289
1290	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1291			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1292	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1293
1294	omap2_mcspi_set_master_mode(master);
1295	pm_runtime_mark_last_busy(mcspi->dev);
1296	pm_runtime_put_autosuspend(mcspi->dev);
1297	return 0;
1298}
1299
1300static int omap_mcspi_runtime_resume(struct device *dev)
1301{
1302	struct omap2_mcspi	*mcspi;
1303	struct spi_master	*master;
1304
1305	master = dev_get_drvdata(dev);
1306	mcspi = spi_master_get_devdata(master);
1307	omap2_mcspi_restore_ctx(mcspi);
1308
1309	return 0;
1310}
1311
1312static struct omap2_mcspi_platform_config omap2_pdata = {
1313	.regs_offset = 0,
1314};
1315
1316static struct omap2_mcspi_platform_config omap4_pdata = {
1317	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1318};
1319
1320static const struct of_device_id omap_mcspi_of_match[] = {
1321	{
1322		.compatible = "ti,omap2-mcspi",
1323		.data = &omap2_pdata,
1324	},
1325	{
1326		.compatible = "ti,omap4-mcspi",
1327		.data = &omap4_pdata,
1328	},
1329	{ },
1330};
1331MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1332
1333static int omap2_mcspi_probe(struct platform_device *pdev)
1334{
1335	struct spi_master	*master;
1336	const struct omap2_mcspi_platform_config *pdata;
1337	struct omap2_mcspi	*mcspi;
1338	struct resource		*r;
1339	int			status = 0, i;
1340	u32			regs_offset = 0;
 
1341	struct device_node	*node = pdev->dev.of_node;
1342	const struct of_device_id *match;
1343
1344	master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1345	if (master == NULL) {
1346		dev_dbg(&pdev->dev, "master allocation failed\n");
1347		return -ENOMEM;
1348	}
1349
1350	/* the spi->mode bits understood by this driver: */
1351	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1352	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1353	master->setup = omap2_mcspi_setup;
1354	master->auto_runtime_pm = true;
1355	master->prepare_message = omap2_mcspi_prepare_message;
1356	master->can_dma = omap2_mcspi_can_dma;
1357	master->transfer_one = omap2_mcspi_transfer_one;
1358	master->set_cs = omap2_mcspi_set_cs;
1359	master->cleanup = omap2_mcspi_cleanup;
1360	master->dev.of_node = node;
1361	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1362	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1363
1364	platform_set_drvdata(pdev, master);
1365
1366	mcspi = spi_master_get_devdata(master);
1367	mcspi->master = master;
1368
1369	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1370	if (match) {
1371		u32 num_cs = 1; /* default number of chipselect */
1372		pdata = match->data;
1373
1374		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1375		master->num_chipselect = num_cs;
1376		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1377			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1378	} else {
1379		pdata = dev_get_platdata(&pdev->dev);
1380		master->num_chipselect = pdata->num_cs;
1381		mcspi->pin_dir = pdata->pin_dir;
 
1382	}
1383	regs_offset = pdata->regs_offset;
1384
 
 
 
 
 
1385	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1386	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1387	if (IS_ERR(mcspi->base)) {
1388		status = PTR_ERR(mcspi->base);
 
 
 
 
 
 
 
 
 
 
1389		goto free_master;
1390	}
1391	mcspi->phys = r->start + regs_offset;
1392	mcspi->base += regs_offset;
1393
1394	mcspi->dev = &pdev->dev;
1395
1396	INIT_LIST_HEAD(&mcspi->ctx.cs);
1397
1398	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1399					   sizeof(struct omap2_mcspi_dma),
1400					   GFP_KERNEL);
1401	if (mcspi->dma_channels == NULL) {
1402		status = -ENOMEM;
1403		goto free_master;
1404	}
1405
1406	for (i = 0; i < master->num_chipselect; i++) {
1407		sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1408		sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1409	}
1410
 
 
 
1411	pm_runtime_use_autosuspend(&pdev->dev);
1412	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1413	pm_runtime_enable(&pdev->dev);
1414
1415	status = omap2_mcspi_master_setup(mcspi);
1416	if (status < 0)
1417		goto disable_pm;
1418
1419	status = devm_spi_register_master(&pdev->dev, master);
1420	if (status < 0)
1421		goto disable_pm;
1422
1423	return status;
1424
 
 
1425disable_pm:
1426	pm_runtime_dont_use_autosuspend(&pdev->dev);
1427	pm_runtime_put_sync(&pdev->dev);
1428	pm_runtime_disable(&pdev->dev);
 
 
1429free_master:
1430	spi_master_put(master);
 
1431	return status;
1432}
1433
1434static int omap2_mcspi_remove(struct platform_device *pdev)
1435{
1436	struct spi_master *master = platform_get_drvdata(pdev);
1437	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 
 
 
 
 
1438
1439	pm_runtime_dont_use_autosuspend(mcspi->dev);
1440	pm_runtime_put_sync(mcspi->dev);
1441	pm_runtime_disable(&pdev->dev);
1442
 
 
 
 
1443	return 0;
1444}
1445
1446/* work with hotplug and coldplug */
1447MODULE_ALIAS("platform:omap2_mcspi");
1448
1449#ifdef	CONFIG_SUSPEND
1450/*
1451 * When SPI wake up from off-mode, CS is in activate state. If it was in
1452 * unactive state when driver was suspend, then force it to unactive state at
1453 * wake up.
1454 */
1455static int omap2_mcspi_resume(struct device *dev)
1456{
1457	struct spi_master	*master = dev_get_drvdata(dev);
1458	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1459	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1460	struct omap2_mcspi_cs	*cs;
1461
1462	pm_runtime_get_sync(mcspi->dev);
1463	list_for_each_entry(cs, &ctx->cs, node) {
1464		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1465			/*
1466			 * We need to toggle CS state for OMAP take this
1467			 * change in account.
1468			 */
1469			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1470			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1471			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1472			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1473		}
1474	}
1475	pm_runtime_mark_last_busy(mcspi->dev);
1476	pm_runtime_put_autosuspend(mcspi->dev);
1477
1478	return pinctrl_pm_select_default_state(dev);
1479}
1480
1481static int omap2_mcspi_suspend(struct device *dev)
1482{
1483	return pinctrl_pm_select_sleep_state(dev);
1484}
1485
1486#else
1487#define omap2_mcspi_suspend	NULL
1488#define	omap2_mcspi_resume	NULL
1489#endif
1490
1491static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1492	.resume = omap2_mcspi_resume,
1493	.suspend = omap2_mcspi_suspend,
1494	.runtime_resume	= omap_mcspi_runtime_resume,
1495};
1496
1497static struct platform_driver omap2_mcspi_driver = {
1498	.driver = {
1499		.name =		"omap2_mcspi",
 
1500		.pm =		&omap2_mcspi_pm_ops,
1501		.of_match_table = omap_mcspi_of_match,
1502	},
1503	.probe =	omap2_mcspi_probe,
1504	.remove =	omap2_mcspi_remove,
1505};
1506
1507module_platform_driver(omap2_mcspi_driver);
1508MODULE_LICENSE("GPL");