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v3.1
   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
  38#include <linux/spi/spi.h>
  39
  40#include <plat/dma.h>
  41#include <plat/clock.h>
  42#include <plat/mcspi.h>
  43
  44#define OMAP2_MCSPI_MAX_FREQ		48000000
  45
  46/* OMAP2 has 3 SPI controllers, while OMAP3 has 4 */
  47#define OMAP2_MCSPI_MAX_CTRL 		4
 
  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
 
 
 
 
 
 
 
 
 
 
 112struct omap2_mcspi {
 113	struct work_struct	work;
 114	/* lock protects queue and registers */
 115	spinlock_t		lock;
 116	struct list_head	msg_queue;
 117	struct spi_master	*master;
 118	/* Virtual base address of the controller */
 119	void __iomem		*base;
 120	unsigned long		phys;
 121	/* SPI1 has 4 channels, while SPI2 has 2 */
 122	struct omap2_mcspi_dma	*dma_channels;
 123	struct  device		*dev;
 
 
 
 124};
 125
 126struct omap2_mcspi_cs {
 127	void __iomem		*base;
 128	unsigned long		phys;
 129	int			word_len;
 130	struct list_head	node;
 131	/* Context save and restore shadow register */
 132	u32			chconf0;
 133};
 134
 135/* used for context save and restore, structure members to be updated whenever
 136 * corresponding registers are modified.
 137 */
 138struct omap2_mcspi_regs {
 139	u32 modulctrl;
 140	u32 wakeupenable;
 141	struct list_head cs;
 142};
 143
 144static struct omap2_mcspi_regs omap2_mcspi_ctx[OMAP2_MCSPI_MAX_CTRL];
 145
 146static struct workqueue_struct *omap2_mcspi_wq;
 147
 148#define MOD_REG_BIT(val, mask, set) do { \
 149	if (set) \
 150		val |= mask; \
 151	else \
 152		val &= ~mask; \
 153} while (0)
 154
 155static inline void mcspi_write_reg(struct spi_master *master,
 156		int idx, u32 val)
 157{
 158	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 159
 160	__raw_writel(val, mcspi->base + idx);
 161}
 162
 163static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 164{
 165	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 166
 167	return __raw_readl(mcspi->base + idx);
 168}
 169
 170static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 171		int idx, u32 val)
 172{
 173	struct omap2_mcspi_cs	*cs = spi->controller_state;
 174
 175	__raw_writel(val, cs->base +  idx);
 176}
 177
 178static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 179{
 180	struct omap2_mcspi_cs	*cs = spi->controller_state;
 181
 182	return __raw_readl(cs->base + idx);
 183}
 184
 185static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 186{
 187	struct omap2_mcspi_cs *cs = spi->controller_state;
 188
 189	return cs->chconf0;
 190}
 191
 192static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 193{
 194	struct omap2_mcspi_cs *cs = spi->controller_state;
 195
 196	cs->chconf0 = val;
 197	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 198	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 199}
 200
 
 
 
 
 
 
 
 
 
 
 201static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 202		int is_read, int enable)
 203{
 204	u32 l, rw;
 205
 206	l = mcspi_cached_chconf0(spi);
 207
 208	if (is_read) /* 1 is read, 0 write */
 209		rw = OMAP2_MCSPI_CHCONF_DMAR;
 210	else
 211		rw = OMAP2_MCSPI_CHCONF_DMAW;
 212
 213	MOD_REG_BIT(l, rw, enable);
 
 
 
 
 214	mcspi_write_chconf0(spi, l);
 215}
 216
 217static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 218{
 
 219	u32 l;
 220
 221	l = enable ? OMAP2_MCSPI_CHCTRL_EN : 0;
 222	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, l);
 
 
 
 
 
 223	/* Flash post-writes */
 224	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 225}
 226
 227static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 228{
 229	u32 l;
 230
 231	l = mcspi_cached_chconf0(spi);
 232	MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active);
 
 
 
 
 233	mcspi_write_chconf0(spi, l);
 234}
 235
 236static void omap2_mcspi_set_master_mode(struct spi_master *master)
 237{
 
 
 238	u32 l;
 239
 240	/* setup when switching from (reset default) slave mode
 
 241	 * to single-channel master mode
 242	 */
 243	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 244	MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_STEST, 0);
 245	MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_MS, 0);
 246	MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1);
 247	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 248
 249	omap2_mcspi_ctx[master->bus_num - 1].modulctrl = l;
 250}
 251
 252static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 
 253{
 254	struct spi_master *spi_cntrl;
 255	struct omap2_mcspi_cs *cs;
 256	spi_cntrl = mcspi->master;
 
 
 
 257
 258	/* McSPI: context restore */
 259	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL,
 260			omap2_mcspi_ctx[spi_cntrl->bus_num - 1].modulctrl);
 261
 262	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE,
 263			omap2_mcspi_ctx[spi_cntrl->bus_num - 1].wakeupenable);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 264
 265	list_for_each_entry(cs, &omap2_mcspi_ctx[spi_cntrl->bus_num - 1].cs,
 266			node)
 267		__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 268}
 269static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
 270{
 271	pm_runtime_put_sync(mcspi->dev);
 
 
 
 
 
 
 
 
 272}
 273
 274static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi)
 275{
 276	return pm_runtime_get_sync(mcspi->dev);
 
 
 
 
 
 
 
 
 
 277}
 278
 279static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 280{
 281	unsigned long timeout;
 282
 283	timeout = jiffies + msecs_to_jiffies(1000);
 284	while (!(__raw_readl(reg) & bit)) {
 285		if (time_after(jiffies, timeout))
 286			return -1;
 
 
 
 
 287		cpu_relax();
 288	}
 289	return 0;
 290}
 291
 292static unsigned
 293omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 294{
 295	struct omap2_mcspi	*mcspi;
 296	struct omap2_mcspi_cs	*cs = spi->controller_state;
 297	struct omap2_mcspi_dma  *mcspi_dma;
 298	unsigned int		count, c;
 299	unsigned long		base, tx_reg, rx_reg;
 300	int			word_len, data_type, element_count;
 301	int			elements = 0;
 302	u32			l;
 303	u8			* rx;
 304	const u8		* tx;
 305	void __iomem		*chstat_reg;
 306
 307	mcspi = spi_master_get_devdata(spi->master);
 308	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 309	l = mcspi_cached_chconf0(spi);
 310
 311	chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 312
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 313	count = xfer->len;
 314	c = count;
 315	word_len = cs->word_len;
 316
 317	base = cs->phys;
 318	tx_reg = base + OMAP2_MCSPI_TX0;
 319	rx_reg = base + OMAP2_MCSPI_RX0;
 320	rx = xfer->rx_buf;
 321	tx = xfer->tx_buf;
 322
 323	if (word_len <= 8) {
 324		data_type = OMAP_DMA_DATA_TYPE_S8;
 
 
 325		element_count = count;
 326	} else if (word_len <= 16) {
 327		data_type = OMAP_DMA_DATA_TYPE_S16;
 328		element_count = count >> 1;
 329	} else /* word_len <= 32 */ {
 330		data_type = OMAP_DMA_DATA_TYPE_S32;
 331		element_count = count >> 2;
 332	}
 333
 334	if (tx != NULL) {
 335		omap_set_dma_transfer_params(mcspi_dma->dma_tx_channel,
 336				data_type, element_count, 1,
 337				OMAP_DMA_SYNC_ELEMENT,
 338				mcspi_dma->dma_tx_sync_dev, 0);
 339
 340		omap_set_dma_dest_params(mcspi_dma->dma_tx_channel, 0,
 341				OMAP_DMA_AMODE_CONSTANT,
 342				tx_reg, 0, 0);
 343
 344		omap_set_dma_src_params(mcspi_dma->dma_tx_channel, 0,
 345				OMAP_DMA_AMODE_POST_INC,
 346				xfer->tx_dma, 0, 0);
 347	}
 348
 349	if (rx != NULL) {
 350		elements = element_count - 1;
 351		if (l & OMAP2_MCSPI_CHCONF_TURBO)
 352			elements--;
 353
 354		omap_set_dma_transfer_params(mcspi_dma->dma_rx_channel,
 355				data_type, elements, 1,
 356				OMAP_DMA_SYNC_ELEMENT,
 357				mcspi_dma->dma_rx_sync_dev, 1);
 358
 359		omap_set_dma_src_params(mcspi_dma->dma_rx_channel, 0,
 360				OMAP_DMA_AMODE_CONSTANT,
 361				rx_reg, 0, 0);
 362
 363		omap_set_dma_dest_params(mcspi_dma->dma_rx_channel, 0,
 364				OMAP_DMA_AMODE_POST_INC,
 365				xfer->rx_dma, 0, 0);
 366	}
 367
 368	if (tx != NULL) {
 369		omap_start_dma(mcspi_dma->dma_tx_channel);
 370		omap2_mcspi_set_dma_req(spi, 0, 1);
 371	}
 372
 373	if (rx != NULL) {
 374		omap_start_dma(mcspi_dma->dma_rx_channel);
 375		omap2_mcspi_set_dma_req(spi, 1, 1);
 376	}
 377
 378	if (tx != NULL) {
 379		wait_for_completion(&mcspi_dma->dma_tx_completion);
 380		dma_unmap_single(&spi->dev, xfer->tx_dma, count, DMA_TO_DEVICE);
 381
 382		/* for TX_ONLY mode, be sure all words have shifted out */
 383		if (rx == NULL) {
 384			if (mcspi_wait_for_reg_bit(chstat_reg,
 385						OMAP2_MCSPI_CHSTAT_TXS) < 0)
 386				dev_err(&spi->dev, "TXS timed out\n");
 387			else if (mcspi_wait_for_reg_bit(chstat_reg,
 388						OMAP2_MCSPI_CHSTAT_EOT) < 0)
 389				dev_err(&spi->dev, "EOT timed out\n");
 390		}
 391	}
 392
 393	if (rx != NULL) {
 394		wait_for_completion(&mcspi_dma->dma_rx_completion);
 395		dma_unmap_single(&spi->dev, xfer->rx_dma, count, DMA_FROM_DEVICE);
 396		omap2_mcspi_set_enable(spi, 0);
 397
 398		if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 399
 400			if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 401				   & OMAP2_MCSPI_CHSTAT_RXS)) {
 402				u32 w;
 403
 404				w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 405				if (word_len <= 8)
 406					((u8 *)xfer->rx_buf)[elements++] = w;
 407				else if (word_len <= 16)
 408					((u16 *)xfer->rx_buf)[elements++] = w;
 409				else /* word_len <= 32 */
 410					((u32 *)xfer->rx_buf)[elements++] = w;
 411			} else {
 412				dev_err(&spi->dev,
 413					"DMA RX penultimate word empty");
 414				count -= (word_len <= 8)  ? 2 :
 415					(word_len <= 16) ? 4 :
 416					/* word_len <= 32 */ 8;
 417				omap2_mcspi_set_enable(spi, 1);
 418				return count;
 419			}
 420		}
 421
 422		if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 423				& OMAP2_MCSPI_CHSTAT_RXS)) {
 424			u32 w;
 425
 426			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 427			if (word_len <= 8)
 428				((u8 *)xfer->rx_buf)[elements] = w;
 429			else if (word_len <= 16)
 430				((u16 *)xfer->rx_buf)[elements] = w;
 431			else /* word_len <= 32 */
 432				((u32 *)xfer->rx_buf)[elements] = w;
 433		} else {
 434			dev_err(&spi->dev, "DMA RX last word empty");
 435			count -= (word_len <= 8)  ? 1 :
 436				 (word_len <= 16) ? 2 :
 437			       /* word_len <= 32 */ 4;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 438		}
 439		omap2_mcspi_set_enable(spi, 1);
 440	}
 441	return count;
 442}
 443
 444static unsigned
 445omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 446{
 447	struct omap2_mcspi	*mcspi;
 448	struct omap2_mcspi_cs	*cs = spi->controller_state;
 449	unsigned int		count, c;
 450	u32			l;
 451	void __iomem		*base = cs->base;
 452	void __iomem		*tx_reg;
 453	void __iomem		*rx_reg;
 454	void __iomem		*chstat_reg;
 455	int			word_len;
 456
 457	mcspi = spi_master_get_devdata(spi->master);
 458	count = xfer->len;
 459	c = count;
 460	word_len = cs->word_len;
 461
 462	l = mcspi_cached_chconf0(spi);
 463
 464	/* We store the pre-calculated register addresses on stack to speed
 465	 * up the transfer loop. */
 466	tx_reg		= base + OMAP2_MCSPI_TX0;
 467	rx_reg		= base + OMAP2_MCSPI_RX0;
 468	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 469
 470	if (c < (word_len>>3))
 471		return 0;
 472
 473	if (word_len <= 8) {
 474		u8		*rx;
 475		const u8	*tx;
 476
 477		rx = xfer->rx_buf;
 478		tx = xfer->tx_buf;
 479
 480		do {
 481			c -= 1;
 482			if (tx != NULL) {
 483				if (mcspi_wait_for_reg_bit(chstat_reg,
 484						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 485					dev_err(&spi->dev, "TXS timed out\n");
 486					goto out;
 487				}
 488				dev_vdbg(&spi->dev, "write-%d %02x\n",
 489						word_len, *tx);
 490				__raw_writel(*tx++, tx_reg);
 491			}
 492			if (rx != NULL) {
 493				if (mcspi_wait_for_reg_bit(chstat_reg,
 494						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 495					dev_err(&spi->dev, "RXS timed out\n");
 496					goto out;
 497				}
 498
 499				if (c == 1 && tx == NULL &&
 500				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 501					omap2_mcspi_set_enable(spi, 0);
 502					*rx++ = __raw_readl(rx_reg);
 503					dev_vdbg(&spi->dev, "read-%d %02x\n",
 504						    word_len, *(rx - 1));
 505					if (mcspi_wait_for_reg_bit(chstat_reg,
 506						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 507						dev_err(&spi->dev,
 508							"RXS timed out\n");
 509						goto out;
 510					}
 511					c = 0;
 512				} else if (c == 0 && tx == NULL) {
 513					omap2_mcspi_set_enable(spi, 0);
 514				}
 515
 516				*rx++ = __raw_readl(rx_reg);
 517				dev_vdbg(&spi->dev, "read-%d %02x\n",
 518						word_len, *(rx - 1));
 519			}
 520		} while (c);
 521	} else if (word_len <= 16) {
 522		u16		*rx;
 523		const u16	*tx;
 524
 525		rx = xfer->rx_buf;
 526		tx = xfer->tx_buf;
 527		do {
 528			c -= 2;
 529			if (tx != NULL) {
 530				if (mcspi_wait_for_reg_bit(chstat_reg,
 531						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 532					dev_err(&spi->dev, "TXS timed out\n");
 533					goto out;
 534				}
 535				dev_vdbg(&spi->dev, "write-%d %04x\n",
 536						word_len, *tx);
 537				__raw_writel(*tx++, tx_reg);
 538			}
 539			if (rx != NULL) {
 540				if (mcspi_wait_for_reg_bit(chstat_reg,
 541						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 542					dev_err(&spi->dev, "RXS timed out\n");
 543					goto out;
 544				}
 545
 546				if (c == 2 && tx == NULL &&
 547				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 548					omap2_mcspi_set_enable(spi, 0);
 549					*rx++ = __raw_readl(rx_reg);
 550					dev_vdbg(&spi->dev, "read-%d %04x\n",
 551						    word_len, *(rx - 1));
 552					if (mcspi_wait_for_reg_bit(chstat_reg,
 553						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 554						dev_err(&spi->dev,
 555							"RXS timed out\n");
 556						goto out;
 557					}
 558					c = 0;
 559				} else if (c == 0 && tx == NULL) {
 560					omap2_mcspi_set_enable(spi, 0);
 561				}
 562
 563				*rx++ = __raw_readl(rx_reg);
 564				dev_vdbg(&spi->dev, "read-%d %04x\n",
 565						word_len, *(rx - 1));
 566			}
 567		} while (c >= 2);
 568	} else if (word_len <= 32) {
 569		u32		*rx;
 570		const u32	*tx;
 571
 572		rx = xfer->rx_buf;
 573		tx = xfer->tx_buf;
 574		do {
 575			c -= 4;
 576			if (tx != NULL) {
 577				if (mcspi_wait_for_reg_bit(chstat_reg,
 578						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 579					dev_err(&spi->dev, "TXS timed out\n");
 580					goto out;
 581				}
 582				dev_vdbg(&spi->dev, "write-%d %08x\n",
 583						word_len, *tx);
 584				__raw_writel(*tx++, tx_reg);
 585			}
 586			if (rx != NULL) {
 587				if (mcspi_wait_for_reg_bit(chstat_reg,
 588						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 589					dev_err(&spi->dev, "RXS timed out\n");
 590					goto out;
 591				}
 592
 593				if (c == 4 && tx == NULL &&
 594				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 595					omap2_mcspi_set_enable(spi, 0);
 596					*rx++ = __raw_readl(rx_reg);
 597					dev_vdbg(&spi->dev, "read-%d %08x\n",
 598						    word_len, *(rx - 1));
 599					if (mcspi_wait_for_reg_bit(chstat_reg,
 600						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 601						dev_err(&spi->dev,
 602							"RXS timed out\n");
 603						goto out;
 604					}
 605					c = 0;
 606				} else if (c == 0 && tx == NULL) {
 607					omap2_mcspi_set_enable(spi, 0);
 608				}
 609
 610				*rx++ = __raw_readl(rx_reg);
 611				dev_vdbg(&spi->dev, "read-%d %08x\n",
 612						word_len, *(rx - 1));
 613			}
 614		} while (c >= 4);
 615	}
 616
 617	/* for TX_ONLY mode, be sure all words have shifted out */
 618	if (xfer->rx_buf == NULL) {
 619		if (mcspi_wait_for_reg_bit(chstat_reg,
 620				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 621			dev_err(&spi->dev, "TXS timed out\n");
 622		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 623				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 624			dev_err(&spi->dev, "EOT timed out\n");
 625
 626		/* disable chan to purge rx datas received in TX_ONLY transfer,
 627		 * otherwise these rx datas will affect the direct following
 628		 * RX_ONLY transfer.
 629		 */
 630		omap2_mcspi_set_enable(spi, 0);
 631	}
 632out:
 633	omap2_mcspi_set_enable(spi, 1);
 634	return count - c;
 635}
 636
 637static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 638{
 639	u32 div;
 640
 641	for (div = 0; div < 15; div++)
 642		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 643			return div;
 644
 645	return 15;
 646}
 647
 648/* called only when no transfer is active to this device */
 649static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 650		struct spi_transfer *t)
 651{
 652	struct omap2_mcspi_cs *cs = spi->controller_state;
 653	struct omap2_mcspi *mcspi;
 654	struct spi_master *spi_cntrl;
 655	u32 l = 0, div = 0;
 656	u8 word_len = spi->bits_per_word;
 657	u32 speed_hz = spi->max_speed_hz;
 658
 659	mcspi = spi_master_get_devdata(spi->master);
 660	spi_cntrl = mcspi->master;
 661
 662	if (t != NULL && t->bits_per_word)
 663		word_len = t->bits_per_word;
 664
 665	cs->word_len = word_len;
 666
 667	if (t && t->speed_hz)
 668		speed_hz = t->speed_hz;
 669
 670	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 671	div = omap2_mcspi_calc_divisor(speed_hz);
 
 
 
 
 
 
 
 
 
 
 672
 673	l = mcspi_cached_chconf0(spi);
 674
 675	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 676	 * REVISIT: this controller could support SPI_3WIRE mode.
 677	 */
 678	l &= ~(OMAP2_MCSPI_CHCONF_IS|OMAP2_MCSPI_CHCONF_DPE1);
 679	l |= OMAP2_MCSPI_CHCONF_DPE0;
 
 
 
 
 
 
 
 680
 681	/* wordlength */
 682	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 683	l |= (word_len - 1) << 7;
 684
 685	/* set chipselect polarity; manage with FORCE */
 686	if (!(spi->mode & SPI_CS_HIGH))
 687		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 688	else
 689		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 690
 691	/* set clock divisor */
 692	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 693	l |= div << 2;
 
 
 
 
 
 
 
 
 
 694
 695	/* set SPI mode 0..3 */
 696	if (spi->mode & SPI_CPOL)
 697		l |= OMAP2_MCSPI_CHCONF_POL;
 698	else
 699		l &= ~OMAP2_MCSPI_CHCONF_POL;
 700	if (spi->mode & SPI_CPHA)
 701		l |= OMAP2_MCSPI_CHCONF_PHA;
 702	else
 703		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 704
 705	mcspi_write_chconf0(spi, l);
 706
 707	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 708			OMAP2_MCSPI_MAX_FREQ >> div,
 709			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 710			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 711
 712	return 0;
 713}
 714
 715static void omap2_mcspi_dma_rx_callback(int lch, u16 ch_status, void *data)
 716{
 717	struct spi_device	*spi = data;
 718	struct omap2_mcspi	*mcspi;
 719	struct omap2_mcspi_dma	*mcspi_dma;
 720
 721	mcspi = spi_master_get_devdata(spi->master);
 722	mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
 723
 724	complete(&mcspi_dma->dma_rx_completion);
 725
 726	/* We must disable the DMA RX request */
 727	omap2_mcspi_set_dma_req(spi, 1, 0);
 728}
 729
 730static void omap2_mcspi_dma_tx_callback(int lch, u16 ch_status, void *data)
 731{
 732	struct spi_device	*spi = data;
 733	struct omap2_mcspi	*mcspi;
 734	struct omap2_mcspi_dma	*mcspi_dma;
 735
 736	mcspi = spi_master_get_devdata(spi->master);
 737	mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
 738
 739	complete(&mcspi_dma->dma_tx_completion);
 740
 741	/* We must disable the DMA TX request */
 742	omap2_mcspi_set_dma_req(spi, 0, 0);
 743}
 744
 745static int omap2_mcspi_request_dma(struct spi_device *spi)
 746{
 747	struct spi_master	*master = spi->master;
 748	struct omap2_mcspi	*mcspi;
 749	struct omap2_mcspi_dma	*mcspi_dma;
 
 
 750
 751	mcspi = spi_master_get_devdata(master);
 752	mcspi_dma = mcspi->dma_channels + spi->chip_select;
 753
 754	if (omap_request_dma(mcspi_dma->dma_rx_sync_dev, "McSPI RX",
 755			omap2_mcspi_dma_rx_callback, spi,
 756			&mcspi_dma->dma_rx_channel)) {
 757		dev_err(&spi->dev, "no RX DMA channel for McSPI\n");
 758		return -EAGAIN;
 759	}
 760
 761	if (omap_request_dma(mcspi_dma->dma_tx_sync_dev, "McSPI TX",
 762			omap2_mcspi_dma_tx_callback, spi,
 763			&mcspi_dma->dma_tx_channel)) {
 764		omap_free_dma(mcspi_dma->dma_rx_channel);
 765		mcspi_dma->dma_rx_channel = -1;
 766		dev_err(&spi->dev, "no TX DMA channel for McSPI\n");
 767		return -EAGAIN;
 768	}
 769
 770	init_completion(&mcspi_dma->dma_rx_completion);
 771	init_completion(&mcspi_dma->dma_tx_completion);
 772
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 773	return 0;
 
 
 
 
 774}
 775
 776static int omap2_mcspi_setup(struct spi_device *spi)
 777{
 778	int			ret;
 779	struct omap2_mcspi	*mcspi;
 
 780	struct omap2_mcspi_dma	*mcspi_dma;
 781	struct omap2_mcspi_cs	*cs = spi->controller_state;
 782
 783	if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
 784		dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
 785			spi->bits_per_word);
 786		return -EINVAL;
 787	}
 788
 789	mcspi = spi_master_get_devdata(spi->master);
 790	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 791
 792	if (!cs) {
 793		cs = kzalloc(sizeof *cs, GFP_KERNEL);
 794		if (!cs)
 795			return -ENOMEM;
 796		cs->base = mcspi->base + spi->chip_select * 0x14;
 797		cs->phys = mcspi->phys + spi->chip_select * 0x14;
 798		cs->chconf0 = 0;
 
 799		spi->controller_state = cs;
 800		/* Link this to context save list */
 801		list_add_tail(&cs->node,
 802			&omap2_mcspi_ctx[mcspi->master->bus_num - 1].cs);
 803	}
 804
 805	if (mcspi_dma->dma_rx_channel == -1
 806			|| mcspi_dma->dma_tx_channel == -1) {
 807		ret = omap2_mcspi_request_dma(spi);
 808		if (ret < 0)
 809			return ret;
 810	}
 811
 812	ret = omap2_mcspi_enable_clocks(mcspi);
 813	if (ret < 0)
 814		return ret;
 815
 816	ret = omap2_mcspi_setup_transfer(spi, NULL);
 817	omap2_mcspi_disable_clocks(mcspi);
 
 818
 819	return ret;
 820}
 821
 822static void omap2_mcspi_cleanup(struct spi_device *spi)
 823{
 824	struct omap2_mcspi	*mcspi;
 825	struct omap2_mcspi_dma	*mcspi_dma;
 826	struct omap2_mcspi_cs	*cs;
 827
 828	mcspi = spi_master_get_devdata(spi->master);
 829
 830	if (spi->controller_state) {
 831		/* Unlink controller state from context save list */
 832		cs = spi->controller_state;
 833		list_del(&cs->node);
 834
 835		kfree(spi->controller_state);
 836	}
 837
 838	if (spi->chip_select < spi->master->num_chipselect) {
 839		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 840
 841		if (mcspi_dma->dma_rx_channel != -1) {
 842			omap_free_dma(mcspi_dma->dma_rx_channel);
 843			mcspi_dma->dma_rx_channel = -1;
 844		}
 845		if (mcspi_dma->dma_tx_channel != -1) {
 846			omap_free_dma(mcspi_dma->dma_tx_channel);
 847			mcspi_dma->dma_tx_channel = -1;
 848		}
 849	}
 850}
 851
 852static void omap2_mcspi_work(struct work_struct *work)
 853{
 854	struct omap2_mcspi	*mcspi;
 855
 856	mcspi = container_of(work, struct omap2_mcspi, work);
 857
 858	if (omap2_mcspi_enable_clocks(mcspi) < 0)
 859		return;
 860
 861	spin_lock_irq(&mcspi->lock);
 862
 863	/* We only enable one channel at a time -- the one whose message is
 864	 * at the head of the queue -- although this controller would gladly
 865	 * arbitrate among multiple channels.  This corresponds to "single
 866	 * channel" master mode.  As a side effect, we need to manage the
 867	 * chipselect with the FORCE bit ... CS != channel enable.
 868	 */
 869	while (!list_empty(&mcspi->msg_queue)) {
 870		struct spi_message		*m;
 871		struct spi_device		*spi;
 872		struct spi_transfer		*t = NULL;
 873		int				cs_active = 0;
 874		struct omap2_mcspi_cs		*cs;
 875		struct omap2_mcspi_device_config *cd;
 876		int				par_override = 0;
 877		int				status = 0;
 878		u32				chconf;
 879
 880		m = container_of(mcspi->msg_queue.next, struct spi_message,
 881				 queue);
 882
 883		list_del_init(&m->queue);
 884		spin_unlock_irq(&mcspi->lock);
 
 
 
 
 
 
 
 
 885
 886		spi = m->spi;
 887		cs = spi->controller_state;
 888		cd = spi->controller_data;
 
 
 889
 890		omap2_mcspi_set_enable(spi, 1);
 891		list_for_each_entry(t, &m->transfers, transfer_list) {
 892			if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
 893				status = -EINVAL;
 
 
 
 
 
 
 
 
 894				break;
 895			}
 896			if (par_override || t->speed_hz || t->bits_per_word) {
 897				par_override = 1;
 898				status = omap2_mcspi_setup_transfer(spi, t);
 899				if (status < 0)
 900					break;
 901				if (!t->speed_hz && !t->bits_per_word)
 902					par_override = 0;
 903			}
 
 
 904
 905			if (!cs_active) {
 906				omap2_mcspi_force_cs(spi, 1);
 907				cs_active = 1;
 908			}
 909
 910			chconf = mcspi_cached_chconf0(spi);
 911			chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
 912			chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
 
 913
 914			if (t->tx_buf == NULL)
 915				chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
 916			else if (t->rx_buf == NULL)
 917				chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
 918
 919			if (cd && cd->turbo_mode && t->tx_buf == NULL) {
 920				/* Turbo mode is for more than one word */
 921				if (t->len > ((cs->word_len + 7) >> 3))
 922					chconf |= OMAP2_MCSPI_CHCONF_TURBO;
 923			}
 
 
 
 
 924
 925			mcspi_write_chconf0(spi, chconf);
 926
 927			if (t->len) {
 928				unsigned	count;
 929
 930				/* RX_ONLY mode needs dummy data in TX reg */
 931				if (t->tx_buf == NULL)
 932					__raw_writel(0, cs->base
 933							+ OMAP2_MCSPI_TX0);
 934
 935				if (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)
 936					count = omap2_mcspi_txrx_dma(spi, t);
 937				else
 938					count = omap2_mcspi_txrx_pio(spi, t);
 939				m->actual_length += count;
 940
 941				if (count != t->len) {
 942					status = -EIO;
 943					break;
 944				}
 945			}
 946
 947			if (t->delay_usecs)
 948				udelay(t->delay_usecs);
 949
 950			/* ignore the "leave it on after last xfer" hint */
 951			if (t->cs_change) {
 952				omap2_mcspi_force_cs(spi, 0);
 953				cs_active = 0;
 
 
 
 
 
 
 
 
 
 
 
 954			}
 955		}
 956
 957		/* Restore defaults if they were overriden */
 958		if (par_override) {
 959			par_override = 0;
 960			status = omap2_mcspi_setup_transfer(spi, NULL);
 961		}
 962
 963		if (cs_active)
 
 964			omap2_mcspi_force_cs(spi, 0);
 
 
 965
 966		omap2_mcspi_set_enable(spi, 0);
 967
 968		m->status = status;
 969		m->complete(m->context);
 
 
 
 
 
 
 
 
 
 970
 971		spin_lock_irq(&mcspi->lock);
 
 
 
 
 
 972	}
 973
 974	spin_unlock_irq(&mcspi->lock);
 975
 976	omap2_mcspi_disable_clocks(mcspi);
 
 
 
 977}
 978
 979static int omap2_mcspi_transfer(struct spi_device *spi, struct spi_message *m)
 
 980{
 
 981	struct omap2_mcspi	*mcspi;
 982	unsigned long		flags;
 983	struct spi_transfer	*t;
 984
 
 
 
 985	m->actual_length = 0;
 986	m->status = 0;
 987
 988	/* reject invalid messages and transfers */
 989	if (list_empty(&m->transfers) || !m->complete)
 990		return -EINVAL;
 991	list_for_each_entry(t, &m->transfers, transfer_list) {
 992		const void	*tx_buf = t->tx_buf;
 993		void		*rx_buf = t->rx_buf;
 994		unsigned	len = t->len;
 995
 996		if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ
 997				|| (len && !(rx_buf || tx_buf))
 998				|| (t->bits_per_word &&
 999					(  t->bits_per_word < 4
1000					|| t->bits_per_word > 32))) {
1001			dev_dbg(&spi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1002					t->speed_hz,
1003					len,
1004					tx_buf ? "tx" : "",
1005					rx_buf ? "rx" : "",
1006					t->bits_per_word);
1007			return -EINVAL;
1008		}
1009		if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
1010			dev_dbg(&spi->dev, "speed_hz %d below minimum %d Hz\n",
1011				t->speed_hz,
1012				OMAP2_MCSPI_MAX_FREQ >> 15);
1013			return -EINVAL;
1014		}
1015
1016		if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1017			continue;
1018
1019		if (tx_buf != NULL) {
1020			t->tx_dma = dma_map_single(&spi->dev, (void *) tx_buf,
1021					len, DMA_TO_DEVICE);
1022			if (dma_mapping_error(&spi->dev, t->tx_dma)) {
1023				dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
1024						'T', len);
1025				return -EINVAL;
1026			}
1027		}
1028		if (rx_buf != NULL) {
1029			t->rx_dma = dma_map_single(&spi->dev, rx_buf, t->len,
1030					DMA_FROM_DEVICE);
1031			if (dma_mapping_error(&spi->dev, t->rx_dma)) {
1032				dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
1033						'R', len);
1034				if (tx_buf != NULL)
1035					dma_unmap_single(&spi->dev, t->tx_dma,
1036							len, DMA_TO_DEVICE);
1037				return -EINVAL;
1038			}
1039		}
1040	}
1041
1042	mcspi = spi_master_get_devdata(spi->master);
1043
1044	spin_lock_irqsave(&mcspi->lock, flags);
1045	list_add_tail(&m->queue, &mcspi->msg_queue);
1046	queue_work(omap2_mcspi_wq, &mcspi->work);
1047	spin_unlock_irqrestore(&mcspi->lock, flags);
1048
1049	return 0;
1050}
1051
1052static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1053{
1054	struct spi_master	*master = mcspi->master;
1055	u32			tmp;
1056	int ret = 0;
1057
1058	ret = omap2_mcspi_enable_clocks(mcspi);
1059	if (ret < 0)
1060		return ret;
1061
1062	tmp = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1063	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, tmp);
1064	omap2_mcspi_ctx[master->bus_num - 1].wakeupenable = tmp;
1065
1066	omap2_mcspi_set_master_mode(master);
1067	omap2_mcspi_disable_clocks(mcspi);
 
1068	return 0;
1069}
1070
1071static int omap_mcspi_runtime_resume(struct device *dev)
1072{
1073	struct omap2_mcspi	*mcspi;
1074	struct spi_master	*master;
1075
1076	master = dev_get_drvdata(dev);
1077	mcspi = spi_master_get_devdata(master);
1078	omap2_mcspi_restore_ctx(mcspi);
1079
1080	return 0;
1081}
1082
 
 
 
1083
1084static int __init omap2_mcspi_probe(struct platform_device *pdev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1085{
1086	struct spi_master	*master;
1087	struct omap2_mcspi_platform_config *pdata = pdev->dev.platform_data;
1088	struct omap2_mcspi	*mcspi;
1089	struct resource		*r;
1090	int			status = 0, i;
 
 
 
 
1091
1092	master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1093	if (master == NULL) {
1094		dev_dbg(&pdev->dev, "master allocation failed\n");
1095		return -ENOMEM;
1096	}
1097
1098	/* the spi->mode bits understood by this driver: */
1099	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1100
1101	if (pdev->id != -1)
1102		master->bus_num = pdev->id;
1103
1104	master->setup = omap2_mcspi_setup;
1105	master->transfer = omap2_mcspi_transfer;
 
1106	master->cleanup = omap2_mcspi_cleanup;
1107	master->num_chipselect = pdata->num_cs;
 
 
1108
1109	dev_set_drvdata(&pdev->dev, master);
1110
1111	mcspi = spi_master_get_devdata(master);
1112	mcspi->master = master;
1113
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1114	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1115	if (r == NULL) {
1116		status = -ENODEV;
1117		goto err1;
1118	}
1119	if (!request_mem_region(r->start, resource_size(r),
1120				dev_name(&pdev->dev))) {
1121		status = -EBUSY;
1122		goto err1;
1123	}
1124
1125	r->start += pdata->regs_offset;
1126	r->end += pdata->regs_offset;
1127	mcspi->phys = r->start;
1128	mcspi->base = ioremap(r->start, resource_size(r));
1129	if (!mcspi->base) {
1130		dev_dbg(&pdev->dev, "can't ioremap MCSPI\n");
1131		status = -ENOMEM;
1132		goto err2;
1133	}
1134
1135	mcspi->dev = &pdev->dev;
1136	INIT_WORK(&mcspi->work, omap2_mcspi_work);
1137
1138	spin_lock_init(&mcspi->lock);
1139	INIT_LIST_HEAD(&mcspi->msg_queue);
1140	INIT_LIST_HEAD(&omap2_mcspi_ctx[master->bus_num - 1].cs);
1141
1142	mcspi->dma_channels = kcalloc(master->num_chipselect,
1143			sizeof(struct omap2_mcspi_dma),
1144			GFP_KERNEL);
1145
1146	if (mcspi->dma_channels == NULL)
1147		goto err2;
 
 
 
 
 
1148
1149	for (i = 0; i < master->num_chipselect; i++) {
1150		char dma_ch_name[14];
 
1151		struct resource *dma_res;
1152
1153		sprintf(dma_ch_name, "rx%d", i);
1154		dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1155							dma_ch_name);
1156		if (!dma_res) {
1157			dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
1158			status = -ENODEV;
1159			break;
1160		}
 
 
 
 
1161
1162		mcspi->dma_channels[i].dma_rx_channel = -1;
1163		mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
1164		sprintf(dma_ch_name, "tx%d", i);
1165		dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1166							dma_ch_name);
1167		if (!dma_res) {
1168			dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
1169			status = -ENODEV;
1170			break;
1171		}
 
 
 
 
 
 
 
 
 
 
 
 
1172
1173		mcspi->dma_channels[i].dma_tx_channel = -1;
1174		mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start;
 
1175	}
1176
 
 
 
 
 
1177	pm_runtime_enable(&pdev->dev);
1178
1179	if (status || omap2_mcspi_master_setup(mcspi) < 0)
1180		goto err3;
 
1181
1182	status = spi_register_master(master);
1183	if (status < 0)
1184		goto err4;
1185
1186	return status;
1187
1188err4:
 
 
1189	spi_master_put(master);
1190err3:
1191	kfree(mcspi->dma_channels);
1192err2:
1193	release_mem_region(r->start, resource_size(r));
1194	iounmap(mcspi->base);
1195err1:
1196	return status;
1197}
1198
1199static int __exit omap2_mcspi_remove(struct platform_device *pdev)
1200{
1201	struct spi_master	*master;
1202	struct omap2_mcspi	*mcspi;
1203	struct omap2_mcspi_dma	*dma_channels;
1204	struct resource		*r;
1205	void __iomem *base;
1206
1207	master = dev_get_drvdata(&pdev->dev);
1208	mcspi = spi_master_get_devdata(master);
1209	dma_channels = mcspi->dma_channels;
1210
1211	omap2_mcspi_disable_clocks(mcspi);
1212	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1213	release_mem_region(r->start, resource_size(r));
1214
1215	base = mcspi->base;
1216	spi_unregister_master(master);
1217	iounmap(base);
1218	kfree(dma_channels);
1219
1220	return 0;
1221}
1222
1223/* work with hotplug and coldplug */
1224MODULE_ALIAS("platform:omap2_mcspi");
1225
1226#ifdef	CONFIG_SUSPEND
1227/*
1228 * When SPI wake up from off-mode, CS is in activate state. If it was in
1229 * unactive state when driver was suspend, then force it to unactive state at
1230 * wake up.
1231 */
1232static int omap2_mcspi_resume(struct device *dev)
1233{
1234	struct spi_master	*master = dev_get_drvdata(dev);
1235	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1236	struct omap2_mcspi_cs *cs;
 
1237
1238	omap2_mcspi_enable_clocks(mcspi);
1239	list_for_each_entry(cs, &omap2_mcspi_ctx[master->bus_num - 1].cs,
1240			    node) {
1241		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1242
1243			/*
1244			 * We need to toggle CS state for OMAP take this
1245			 * change in account.
1246			 */
1247			MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 1);
1248			__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1249			MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 0);
1250			__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1251		}
1252	}
1253	omap2_mcspi_disable_clocks(mcspi);
 
1254	return 0;
1255}
1256#else
1257#define	omap2_mcspi_resume	NULL
1258#endif
1259
1260static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1261	.resume = omap2_mcspi_resume,
1262	.runtime_resume	= omap_mcspi_runtime_resume,
1263};
1264
1265static struct platform_driver omap2_mcspi_driver = {
1266	.driver = {
1267		.name =		"omap2_mcspi",
1268		.owner =	THIS_MODULE,
1269		.pm =		&omap2_mcspi_pm_ops
 
1270	},
1271	.remove =	__exit_p(omap2_mcspi_remove),
 
1272};
1273
1274
1275static int __init omap2_mcspi_init(void)
1276{
1277	omap2_mcspi_wq = create_singlethread_workqueue(
1278				omap2_mcspi_driver.driver.name);
1279	if (omap2_mcspi_wq == NULL)
1280		return -1;
1281	return platform_driver_probe(&omap2_mcspi_driver, omap2_mcspi_probe);
1282}
1283subsys_initcall(omap2_mcspi_init);
1284
1285static void __exit omap2_mcspi_exit(void)
1286{
1287	platform_driver_unregister(&omap2_mcspi_driver);
1288
1289	destroy_workqueue(omap2_mcspi_wq);
1290}
1291module_exit(omap2_mcspi_exit);
1292
1293MODULE_LICENSE("GPL");
v3.15
   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/interrupt.h>
  26#include <linux/module.h>
  27#include <linux/device.h>
  28#include <linux/delay.h>
  29#include <linux/dma-mapping.h>
  30#include <linux/dmaengine.h>
  31#include <linux/omap-dma.h>
  32#include <linux/platform_device.h>
  33#include <linux/err.h>
  34#include <linux/clk.h>
  35#include <linux/io.h>
  36#include <linux/slab.h>
  37#include <linux/pm_runtime.h>
  38#include <linux/of.h>
  39#include <linux/of_device.h>
  40#include <linux/gcd.h>
  41
  42#include <linux/spi/spi.h>
  43
  44#include <linux/platform_data/spi-omap2-mcspi.h>
 
 
  45
  46#define OMAP2_MCSPI_MAX_FREQ		48000000
  47#define OMAP2_MCSPI_MAX_DIVIDER		4096
  48#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  49#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  50#define SPI_AUTOSUSPEND_TIMEOUT		2000
  51
  52#define OMAP2_MCSPI_REVISION		0x00
  53#define OMAP2_MCSPI_SYSSTATUS		0x14
  54#define OMAP2_MCSPI_IRQSTATUS		0x18
  55#define OMAP2_MCSPI_IRQENABLE		0x1c
  56#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  57#define OMAP2_MCSPI_SYST		0x24
  58#define OMAP2_MCSPI_MODULCTRL		0x28
  59#define OMAP2_MCSPI_XFERLEVEL		0x7c
  60
  61/* per-channel banks, 0x14 bytes each, first is: */
  62#define OMAP2_MCSPI_CHCONF0		0x2c
  63#define OMAP2_MCSPI_CHSTAT0		0x30
  64#define OMAP2_MCSPI_CHCTRL0		0x34
  65#define OMAP2_MCSPI_TX0			0x38
  66#define OMAP2_MCSPI_RX0			0x3c
  67
  68/* per-register bitmasks: */
  69#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  70
  71#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  72#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  73#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  74
  75#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  76#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  77#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  78#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  79#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  80#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  81#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  82#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  83#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  84#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  85#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  86#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  87#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  88#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  89#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  90#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  91#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  92#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  93
  94#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  95#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  96#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  97#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  98
  99#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
 100#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
 101
 102#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
 103
 104/* We have 2 DMA channels per CS, one for RX and one for TX */
 105struct omap2_mcspi_dma {
 106	struct dma_chan *dma_tx;
 107	struct dma_chan *dma_rx;
 108
 109	int dma_tx_sync_dev;
 110	int dma_rx_sync_dev;
 111
 112	struct completion dma_tx_completion;
 113	struct completion dma_rx_completion;
 114
 115	char dma_rx_ch_name[14];
 116	char dma_tx_ch_name[14];
 117};
 118
 119/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 120 * cache operations; better heuristics consider wordsize and bitrate.
 121 */
 122#define DMA_MIN_BYTES			160
 123
 124
 125/*
 126 * Used for context save and restore, structure members to be updated whenever
 127 * corresponding registers are modified.
 128 */
 129struct omap2_mcspi_regs {
 130	u32 modulctrl;
 131	u32 wakeupenable;
 132	struct list_head cs;
 133};
 134
 135struct omap2_mcspi {
 
 
 
 
 136	struct spi_master	*master;
 137	/* Virtual base address of the controller */
 138	void __iomem		*base;
 139	unsigned long		phys;
 140	/* SPI1 has 4 channels, while SPI2 has 2 */
 141	struct omap2_mcspi_dma	*dma_channels;
 142	struct device		*dev;
 143	struct omap2_mcspi_regs ctx;
 144	int			fifo_depth;
 145	unsigned int		pin_dir:1;
 146};
 147
 148struct omap2_mcspi_cs {
 149	void __iomem		*base;
 150	unsigned long		phys;
 151	int			word_len;
 152	struct list_head	node;
 153	/* Context save and restore shadow register */
 154	u32			chconf0, chctrl0;
 
 
 
 
 
 
 
 
 
 155};
 156
 
 
 
 
 
 
 
 
 
 
 
 157static inline void mcspi_write_reg(struct spi_master *master,
 158		int idx, u32 val)
 159{
 160	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 161
 162	writel_relaxed(val, mcspi->base + idx);
 163}
 164
 165static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 166{
 167	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 168
 169	return readl_relaxed(mcspi->base + idx);
 170}
 171
 172static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 173		int idx, u32 val)
 174{
 175	struct omap2_mcspi_cs	*cs = spi->controller_state;
 176
 177	writel_relaxed(val, cs->base +  idx);
 178}
 179
 180static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 181{
 182	struct omap2_mcspi_cs	*cs = spi->controller_state;
 183
 184	return readl_relaxed(cs->base + idx);
 185}
 186
 187static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 188{
 189	struct omap2_mcspi_cs *cs = spi->controller_state;
 190
 191	return cs->chconf0;
 192}
 193
 194static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 195{
 196	struct omap2_mcspi_cs *cs = spi->controller_state;
 197
 198	cs->chconf0 = val;
 199	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 200	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 201}
 202
 203static inline int mcspi_bytes_per_word(int word_len)
 204{
 205	if (word_len <= 8)
 206		return 1;
 207	else if (word_len <= 16)
 208		return 2;
 209	else /* word_len <= 32 */
 210		return 4;
 211}
 212
 213static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 214		int is_read, int enable)
 215{
 216	u32 l, rw;
 217
 218	l = mcspi_cached_chconf0(spi);
 219
 220	if (is_read) /* 1 is read, 0 write */
 221		rw = OMAP2_MCSPI_CHCONF_DMAR;
 222	else
 223		rw = OMAP2_MCSPI_CHCONF_DMAW;
 224
 225	if (enable)
 226		l |= rw;
 227	else
 228		l &= ~rw;
 229
 230	mcspi_write_chconf0(spi, l);
 231}
 232
 233static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 234{
 235	struct omap2_mcspi_cs *cs = spi->controller_state;
 236	u32 l;
 237
 238	l = cs->chctrl0;
 239	if (enable)
 240		l |= OMAP2_MCSPI_CHCTRL_EN;
 241	else
 242		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 243	cs->chctrl0 = l;
 244	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 245	/* Flash post-writes */
 246	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 247}
 248
 249static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 250{
 251	u32 l;
 252
 253	l = mcspi_cached_chconf0(spi);
 254	if (cs_active)
 255		l |= OMAP2_MCSPI_CHCONF_FORCE;
 256	else
 257		l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 258
 259	mcspi_write_chconf0(spi, l);
 260}
 261
 262static void omap2_mcspi_set_master_mode(struct spi_master *master)
 263{
 264	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 265	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 266	u32 l;
 267
 268	/*
 269	 * Setup when switching from (reset default) slave mode
 270	 * to single-channel master mode
 271	 */
 272	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 273	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
 274	l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 
 275	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 276
 277	ctx->modulctrl = l;
 278}
 279
 280static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 281				struct spi_transfer *t, int enable)
 282{
 283	struct spi_master *master = spi->master;
 284	struct omap2_mcspi_cs *cs = spi->controller_state;
 285	struct omap2_mcspi *mcspi;
 286	unsigned int wcnt;
 287	int max_fifo_depth, fifo_depth, bytes_per_word;
 288	u32 chconf, xferlevel;
 289
 290	mcspi = spi_master_get_devdata(master);
 
 
 291
 292	chconf = mcspi_cached_chconf0(spi);
 293	if (enable) {
 294		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 295		if (t->len % bytes_per_word != 0)
 296			goto disable_fifo;
 297
 298		if (t->rx_buf != NULL && t->tx_buf != NULL)
 299			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 300		else
 301			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 302
 303		fifo_depth = gcd(t->len, max_fifo_depth);
 304		if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
 305			goto disable_fifo;
 306
 307		wcnt = t->len / bytes_per_word;
 308		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 309			goto disable_fifo;
 310
 311		xferlevel = wcnt << 16;
 312		if (t->rx_buf != NULL) {
 313			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 314			xferlevel |= (fifo_depth - 1) << 8;
 315		}
 316		if (t->tx_buf != NULL) {
 317			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 318			xferlevel |= fifo_depth - 1;
 319		}
 320
 321		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 322		mcspi_write_chconf0(spi, chconf);
 323		mcspi->fifo_depth = fifo_depth;
 324
 325		return;
 326	}
 327
 328disable_fifo:
 329	if (t->rx_buf != NULL)
 330		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 331	else
 332		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 333
 334	mcspi_write_chconf0(spi, chconf);
 335	mcspi->fifo_depth = 0;
 336}
 337
 338static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 339{
 340	struct spi_master	*spi_cntrl = mcspi->master;
 341	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 342	struct omap2_mcspi_cs	*cs;
 343
 344	/* McSPI: context restore */
 345	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
 346	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
 347
 348	list_for_each_entry(cs, &ctx->cs, node)
 349		writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 350}
 351
 352static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 353{
 354	unsigned long timeout;
 355
 356	timeout = jiffies + msecs_to_jiffies(1000);
 357	while (!(readl_relaxed(reg) & bit)) {
 358		if (time_after(jiffies, timeout)) {
 359			if (!(readl_relaxed(reg) & bit))
 360				return -ETIMEDOUT;
 361			else
 362				return 0;
 363		}
 364		cpu_relax();
 365	}
 366	return 0;
 367}
 368
 369static void omap2_mcspi_rx_callback(void *data)
 370{
 371	struct spi_device *spi = data;
 372	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 373	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 374
 375	/* We must disable the DMA RX request */
 376	omap2_mcspi_set_dma_req(spi, 1, 0);
 377
 378	complete(&mcspi_dma->dma_rx_completion);
 379}
 380
 381static void omap2_mcspi_tx_callback(void *data)
 382{
 383	struct spi_device *spi = data;
 384	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 385	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 386
 387	/* We must disable the DMA TX request */
 388	omap2_mcspi_set_dma_req(spi, 0, 0);
 389
 390	complete(&mcspi_dma->dma_tx_completion);
 391}
 392
 393static void omap2_mcspi_tx_dma(struct spi_device *spi,
 394				struct spi_transfer *xfer,
 395				struct dma_slave_config cfg)
 396{
 397	struct omap2_mcspi	*mcspi;
 
 398	struct omap2_mcspi_dma  *mcspi_dma;
 399	unsigned int		count;
 
 
 
 
 
 
 
 400
 401	mcspi = spi_master_get_devdata(spi->master);
 402	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 403	count = xfer->len;
 404
 405	if (mcspi_dma->dma_tx) {
 406		struct dma_async_tx_descriptor *tx;
 407		struct scatterlist sg;
 408
 409		dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 410
 411		sg_init_table(&sg, 1);
 412		sg_dma_address(&sg) = xfer->tx_dma;
 413		sg_dma_len(&sg) = xfer->len;
 414
 415		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
 416		DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 417		if (tx) {
 418			tx->callback = omap2_mcspi_tx_callback;
 419			tx->callback_param = spi;
 420			dmaengine_submit(tx);
 421		} else {
 422			/* FIXME: fall back to PIO? */
 423		}
 424	}
 425	dma_async_issue_pending(mcspi_dma->dma_tx);
 426	omap2_mcspi_set_dma_req(spi, 0, 1);
 427
 428}
 429
 430static unsigned
 431omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 432				struct dma_slave_config cfg,
 433				unsigned es)
 434{
 435	struct omap2_mcspi	*mcspi;
 436	struct omap2_mcspi_dma  *mcspi_dma;
 437	unsigned int		count, dma_count;
 438	u32			l;
 439	int			elements = 0;
 440	int			word_len, element_count;
 441	struct omap2_mcspi_cs	*cs = spi->controller_state;
 442	mcspi = spi_master_get_devdata(spi->master);
 443	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 444	count = xfer->len;
 445	dma_count = xfer->len;
 
 446
 447	if (mcspi->fifo_depth == 0)
 448		dma_count -= es;
 
 
 
 449
 450	word_len = cs->word_len;
 451	l = mcspi_cached_chconf0(spi);
 452
 453	if (word_len <= 8)
 454		element_count = count;
 455	else if (word_len <= 16)
 
 456		element_count = count >> 1;
 457	else /* word_len <= 32 */
 
 458		element_count = count >> 2;
 
 459
 460	if (mcspi_dma->dma_rx) {
 461		struct dma_async_tx_descriptor *tx;
 462		struct scatterlist sg;
 463
 464		dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 465
 466		if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 467			dma_count -= es;
 468
 469		sg_init_table(&sg, 1);
 470		sg_dma_address(&sg) = xfer->rx_dma;
 471		sg_dma_len(&sg) = dma_count;
 472
 473		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
 474				DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
 475				DMA_CTRL_ACK);
 476		if (tx) {
 477			tx->callback = omap2_mcspi_rx_callback;
 478			tx->callback_param = spi;
 479			dmaengine_submit(tx);
 480		} else {
 481				/* FIXME: fall back to PIO? */
 482		}
 
 
 
 
 
 
 
 
 
 483	}
 484
 485	dma_async_issue_pending(mcspi_dma->dma_rx);
 486	omap2_mcspi_set_dma_req(spi, 1, 1);
 
 
 487
 488	wait_for_completion(&mcspi_dma->dma_rx_completion);
 489	dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
 490			 DMA_FROM_DEVICE);
 
 491
 492	if (mcspi->fifo_depth > 0)
 493		return count;
 
 494
 495	omap2_mcspi_set_enable(spi, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 496
 497	elements = element_count - 1;
 498
 499	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 500		elements--;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 501
 502		if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 503				   & OMAP2_MCSPI_CHSTAT_RXS)) {
 504			u32 w;
 505
 506			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 507			if (word_len <= 8)
 508				((u8 *)xfer->rx_buf)[elements++] = w;
 509			else if (word_len <= 16)
 510				((u16 *)xfer->rx_buf)[elements++] = w;
 511			else /* word_len <= 32 */
 512				((u32 *)xfer->rx_buf)[elements++] = w;
 513		} else {
 514			int bytes_per_word = mcspi_bytes_per_word(word_len);
 515			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 516			count -= (bytes_per_word << 1);
 517			omap2_mcspi_set_enable(spi, 1);
 518			return count;
 519		}
 520	}
 521	if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 522				& OMAP2_MCSPI_CHSTAT_RXS)) {
 523		u32 w;
 524
 525		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 526		if (word_len <= 8)
 527			((u8 *)xfer->rx_buf)[elements] = w;
 528		else if (word_len <= 16)
 529			((u16 *)xfer->rx_buf)[elements] = w;
 530		else /* word_len <= 32 */
 531			((u32 *)xfer->rx_buf)[elements] = w;
 532	} else {
 533		dev_err(&spi->dev, "DMA RX last word empty\n");
 534		count -= mcspi_bytes_per_word(word_len);
 535	}
 536	omap2_mcspi_set_enable(spi, 1);
 537	return count;
 538}
 539
 540static unsigned
 541omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 542{
 543	struct omap2_mcspi	*mcspi;
 544	struct omap2_mcspi_cs	*cs = spi->controller_state;
 545	struct omap2_mcspi_dma  *mcspi_dma;
 546	unsigned int		count;
 547	u32			l;
 548	u8			*rx;
 549	const u8		*tx;
 550	struct dma_slave_config	cfg;
 551	enum dma_slave_buswidth width;
 552	unsigned es;
 553	u32			burst;
 554	void __iomem		*chstat_reg;
 555	void __iomem            *irqstat_reg;
 556	int			wait_res;
 557
 558	mcspi = spi_master_get_devdata(spi->master);
 559	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 560	l = mcspi_cached_chconf0(spi);
 561
 562
 563	if (cs->word_len <= 8) {
 564		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 565		es = 1;
 566	} else if (cs->word_len <= 16) {
 567		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 568		es = 2;
 569	} else {
 570		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 571		es = 4;
 572	}
 573
 574	count = xfer->len;
 575	burst = 1;
 576
 577	if (mcspi->fifo_depth > 0) {
 578		if (count > mcspi->fifo_depth)
 579			burst = mcspi->fifo_depth / es;
 580		else
 581			burst = count / es;
 582	}
 583
 584	memset(&cfg, 0, sizeof(cfg));
 585	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 586	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 587	cfg.src_addr_width = width;
 588	cfg.dst_addr_width = width;
 589	cfg.src_maxburst = burst;
 590	cfg.dst_maxburst = burst;
 591
 592	rx = xfer->rx_buf;
 593	tx = xfer->tx_buf;
 594
 595	if (tx != NULL)
 596		omap2_mcspi_tx_dma(spi, xfer, cfg);
 597
 598	if (rx != NULL)
 599		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 600
 601	if (tx != NULL) {
 602		wait_for_completion(&mcspi_dma->dma_tx_completion);
 603		dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len,
 604				 DMA_TO_DEVICE);
 605
 606		if (mcspi->fifo_depth > 0) {
 607			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 608
 609			if (mcspi_wait_for_reg_bit(irqstat_reg,
 610						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 611				dev_err(&spi->dev, "EOW timed out\n");
 612
 613			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 614					OMAP2_MCSPI_IRQSTATUS_EOW);
 615		}
 616
 617		/* for TX_ONLY mode, be sure all words have shifted out */
 618		if (rx == NULL) {
 619			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 620			if (mcspi->fifo_depth > 0) {
 621				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 622						OMAP2_MCSPI_CHSTAT_TXFFE);
 623				if (wait_res < 0)
 624					dev_err(&spi->dev, "TXFFE timed out\n");
 625			} else {
 626				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 627						OMAP2_MCSPI_CHSTAT_TXS);
 628				if (wait_res < 0)
 629					dev_err(&spi->dev, "TXS timed out\n");
 630			}
 631			if (wait_res >= 0 &&
 632				(mcspi_wait_for_reg_bit(chstat_reg,
 633					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 634				dev_err(&spi->dev, "EOT timed out\n");
 635		}
 
 636	}
 637	return count;
 638}
 639
 640static unsigned
 641omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 642{
 643	struct omap2_mcspi	*mcspi;
 644	struct omap2_mcspi_cs	*cs = spi->controller_state;
 645	unsigned int		count, c;
 646	u32			l;
 647	void __iomem		*base = cs->base;
 648	void __iomem		*tx_reg;
 649	void __iomem		*rx_reg;
 650	void __iomem		*chstat_reg;
 651	int			word_len;
 652
 653	mcspi = spi_master_get_devdata(spi->master);
 654	count = xfer->len;
 655	c = count;
 656	word_len = cs->word_len;
 657
 658	l = mcspi_cached_chconf0(spi);
 659
 660	/* We store the pre-calculated register addresses on stack to speed
 661	 * up the transfer loop. */
 662	tx_reg		= base + OMAP2_MCSPI_TX0;
 663	rx_reg		= base + OMAP2_MCSPI_RX0;
 664	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 665
 666	if (c < (word_len>>3))
 667		return 0;
 668
 669	if (word_len <= 8) {
 670		u8		*rx;
 671		const u8	*tx;
 672
 673		rx = xfer->rx_buf;
 674		tx = xfer->tx_buf;
 675
 676		do {
 677			c -= 1;
 678			if (tx != NULL) {
 679				if (mcspi_wait_for_reg_bit(chstat_reg,
 680						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 681					dev_err(&spi->dev, "TXS timed out\n");
 682					goto out;
 683				}
 684				dev_vdbg(&spi->dev, "write-%d %02x\n",
 685						word_len, *tx);
 686				writel_relaxed(*tx++, tx_reg);
 687			}
 688			if (rx != NULL) {
 689				if (mcspi_wait_for_reg_bit(chstat_reg,
 690						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 691					dev_err(&spi->dev, "RXS timed out\n");
 692					goto out;
 693				}
 694
 695				if (c == 1 && tx == NULL &&
 696				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 697					omap2_mcspi_set_enable(spi, 0);
 698					*rx++ = readl_relaxed(rx_reg);
 699					dev_vdbg(&spi->dev, "read-%d %02x\n",
 700						    word_len, *(rx - 1));
 701					if (mcspi_wait_for_reg_bit(chstat_reg,
 702						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 703						dev_err(&spi->dev,
 704							"RXS timed out\n");
 705						goto out;
 706					}
 707					c = 0;
 708				} else if (c == 0 && tx == NULL) {
 709					omap2_mcspi_set_enable(spi, 0);
 710				}
 711
 712				*rx++ = readl_relaxed(rx_reg);
 713				dev_vdbg(&spi->dev, "read-%d %02x\n",
 714						word_len, *(rx - 1));
 715			}
 716		} while (c);
 717	} else if (word_len <= 16) {
 718		u16		*rx;
 719		const u16	*tx;
 720
 721		rx = xfer->rx_buf;
 722		tx = xfer->tx_buf;
 723		do {
 724			c -= 2;
 725			if (tx != NULL) {
 726				if (mcspi_wait_for_reg_bit(chstat_reg,
 727						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 728					dev_err(&spi->dev, "TXS timed out\n");
 729					goto out;
 730				}
 731				dev_vdbg(&spi->dev, "write-%d %04x\n",
 732						word_len, *tx);
 733				writel_relaxed(*tx++, tx_reg);
 734			}
 735			if (rx != NULL) {
 736				if (mcspi_wait_for_reg_bit(chstat_reg,
 737						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 738					dev_err(&spi->dev, "RXS timed out\n");
 739					goto out;
 740				}
 741
 742				if (c == 2 && tx == NULL &&
 743				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 744					omap2_mcspi_set_enable(spi, 0);
 745					*rx++ = readl_relaxed(rx_reg);
 746					dev_vdbg(&spi->dev, "read-%d %04x\n",
 747						    word_len, *(rx - 1));
 748					if (mcspi_wait_for_reg_bit(chstat_reg,
 749						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 750						dev_err(&spi->dev,
 751							"RXS timed out\n");
 752						goto out;
 753					}
 754					c = 0;
 755				} else if (c == 0 && tx == NULL) {
 756					omap2_mcspi_set_enable(spi, 0);
 757				}
 758
 759				*rx++ = readl_relaxed(rx_reg);
 760				dev_vdbg(&spi->dev, "read-%d %04x\n",
 761						word_len, *(rx - 1));
 762			}
 763		} while (c >= 2);
 764	} else if (word_len <= 32) {
 765		u32		*rx;
 766		const u32	*tx;
 767
 768		rx = xfer->rx_buf;
 769		tx = xfer->tx_buf;
 770		do {
 771			c -= 4;
 772			if (tx != NULL) {
 773				if (mcspi_wait_for_reg_bit(chstat_reg,
 774						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 775					dev_err(&spi->dev, "TXS timed out\n");
 776					goto out;
 777				}
 778				dev_vdbg(&spi->dev, "write-%d %08x\n",
 779						word_len, *tx);
 780				writel_relaxed(*tx++, tx_reg);
 781			}
 782			if (rx != NULL) {
 783				if (mcspi_wait_for_reg_bit(chstat_reg,
 784						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 785					dev_err(&spi->dev, "RXS timed out\n");
 786					goto out;
 787				}
 788
 789				if (c == 4 && tx == NULL &&
 790				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 791					omap2_mcspi_set_enable(spi, 0);
 792					*rx++ = readl_relaxed(rx_reg);
 793					dev_vdbg(&spi->dev, "read-%d %08x\n",
 794						    word_len, *(rx - 1));
 795					if (mcspi_wait_for_reg_bit(chstat_reg,
 796						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 797						dev_err(&spi->dev,
 798							"RXS timed out\n");
 799						goto out;
 800					}
 801					c = 0;
 802				} else if (c == 0 && tx == NULL) {
 803					omap2_mcspi_set_enable(spi, 0);
 804				}
 805
 806				*rx++ = readl_relaxed(rx_reg);
 807				dev_vdbg(&spi->dev, "read-%d %08x\n",
 808						word_len, *(rx - 1));
 809			}
 810		} while (c >= 4);
 811	}
 812
 813	/* for TX_ONLY mode, be sure all words have shifted out */
 814	if (xfer->rx_buf == NULL) {
 815		if (mcspi_wait_for_reg_bit(chstat_reg,
 816				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 817			dev_err(&spi->dev, "TXS timed out\n");
 818		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 819				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 820			dev_err(&spi->dev, "EOT timed out\n");
 821
 822		/* disable chan to purge rx datas received in TX_ONLY transfer,
 823		 * otherwise these rx datas will affect the direct following
 824		 * RX_ONLY transfer.
 825		 */
 826		omap2_mcspi_set_enable(spi, 0);
 827	}
 828out:
 829	omap2_mcspi_set_enable(spi, 1);
 830	return count - c;
 831}
 832
 833static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 834{
 835	u32 div;
 836
 837	for (div = 0; div < 15; div++)
 838		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 839			return div;
 840
 841	return 15;
 842}
 843
 844/* called only when no transfer is active to this device */
 845static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 846		struct spi_transfer *t)
 847{
 848	struct omap2_mcspi_cs *cs = spi->controller_state;
 849	struct omap2_mcspi *mcspi;
 850	struct spi_master *spi_cntrl;
 851	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 852	u8 word_len = spi->bits_per_word;
 853	u32 speed_hz = spi->max_speed_hz;
 854
 855	mcspi = spi_master_get_devdata(spi->master);
 856	spi_cntrl = mcspi->master;
 857
 858	if (t != NULL && t->bits_per_word)
 859		word_len = t->bits_per_word;
 860
 861	cs->word_len = word_len;
 862
 863	if (t && t->speed_hz)
 864		speed_hz = t->speed_hz;
 865
 866	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 867	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 868		clkd = omap2_mcspi_calc_divisor(speed_hz);
 869		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 870		clkg = 0;
 871	} else {
 872		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 873		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 874		clkd = (div - 1) & 0xf;
 875		extclk = (div - 1) >> 4;
 876		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 877	}
 878
 879	l = mcspi_cached_chconf0(spi);
 880
 881	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 882	 * REVISIT: this controller could support SPI_3WIRE mode.
 883	 */
 884	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 885		l &= ~OMAP2_MCSPI_CHCONF_IS;
 886		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 887		l |= OMAP2_MCSPI_CHCONF_DPE0;
 888	} else {
 889		l |= OMAP2_MCSPI_CHCONF_IS;
 890		l |= OMAP2_MCSPI_CHCONF_DPE1;
 891		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 892	}
 893
 894	/* wordlength */
 895	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 896	l |= (word_len - 1) << 7;
 897
 898	/* set chipselect polarity; manage with FORCE */
 899	if (!(spi->mode & SPI_CS_HIGH))
 900		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 901	else
 902		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 903
 904	/* set clock divisor */
 905	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 906	l |= clkd << 2;
 907
 908	/* set clock granularity */
 909	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 910	l |= clkg;
 911	if (clkg) {
 912		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 913		cs->chctrl0 |= extclk << 8;
 914		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 915	}
 916
 917	/* set SPI mode 0..3 */
 918	if (spi->mode & SPI_CPOL)
 919		l |= OMAP2_MCSPI_CHCONF_POL;
 920	else
 921		l &= ~OMAP2_MCSPI_CHCONF_POL;
 922	if (spi->mode & SPI_CPHA)
 923		l |= OMAP2_MCSPI_CHCONF_PHA;
 924	else
 925		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 926
 927	mcspi_write_chconf0(spi, l);
 928
 929	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 930			speed_hz,
 931			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 932			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 933
 934	return 0;
 935}
 936
 937/*
 938 * Note that we currently allow DMA only if we get a channel
 939 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 940 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 941static int omap2_mcspi_request_dma(struct spi_device *spi)
 942{
 943	struct spi_master	*master = spi->master;
 944	struct omap2_mcspi	*mcspi;
 945	struct omap2_mcspi_dma	*mcspi_dma;
 946	dma_cap_mask_t mask;
 947	unsigned sig;
 948
 949	mcspi = spi_master_get_devdata(master);
 950	mcspi_dma = mcspi->dma_channels + spi->chip_select;
 951
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 952	init_completion(&mcspi_dma->dma_rx_completion);
 953	init_completion(&mcspi_dma->dma_tx_completion);
 954
 955	dma_cap_zero(mask);
 956	dma_cap_set(DMA_SLAVE, mask);
 957	sig = mcspi_dma->dma_rx_sync_dev;
 958
 959	mcspi_dma->dma_rx =
 960		dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 961						 &sig, &master->dev,
 962						 mcspi_dma->dma_rx_ch_name);
 963	if (!mcspi_dma->dma_rx)
 964		goto no_dma;
 965
 966	sig = mcspi_dma->dma_tx_sync_dev;
 967	mcspi_dma->dma_tx =
 968		dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 969						 &sig, &master->dev,
 970						 mcspi_dma->dma_tx_ch_name);
 971
 972	if (!mcspi_dma->dma_tx) {
 973		dma_release_channel(mcspi_dma->dma_rx);
 974		mcspi_dma->dma_rx = NULL;
 975		goto no_dma;
 976	}
 977
 978	return 0;
 979
 980no_dma:
 981	dev_warn(&spi->dev, "not using DMA for McSPI\n");
 982	return -EAGAIN;
 983}
 984
 985static int omap2_mcspi_setup(struct spi_device *spi)
 986{
 987	int			ret;
 988	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
 989	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 990	struct omap2_mcspi_dma	*mcspi_dma;
 991	struct omap2_mcspi_cs	*cs = spi->controller_state;
 992
 
 
 
 
 
 
 
 993	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 994
 995	if (!cs) {
 996		cs = kzalloc(sizeof *cs, GFP_KERNEL);
 997		if (!cs)
 998			return -ENOMEM;
 999		cs->base = mcspi->base + spi->chip_select * 0x14;
1000		cs->phys = mcspi->phys + spi->chip_select * 0x14;
1001		cs->chconf0 = 0;
1002		cs->chctrl0 = 0;
1003		spi->controller_state = cs;
1004		/* Link this to context save list */
1005		list_add_tail(&cs->node, &ctx->cs);
 
1006	}
1007
1008	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
 
1009		ret = omap2_mcspi_request_dma(spi);
1010		if (ret < 0 && ret != -EAGAIN)
1011			return ret;
1012	}
1013
1014	ret = pm_runtime_get_sync(mcspi->dev);
1015	if (ret < 0)
1016		return ret;
1017
1018	ret = omap2_mcspi_setup_transfer(spi, NULL);
1019	pm_runtime_mark_last_busy(mcspi->dev);
1020	pm_runtime_put_autosuspend(mcspi->dev);
1021
1022	return ret;
1023}
1024
1025static void omap2_mcspi_cleanup(struct spi_device *spi)
1026{
1027	struct omap2_mcspi	*mcspi;
1028	struct omap2_mcspi_dma	*mcspi_dma;
1029	struct omap2_mcspi_cs	*cs;
1030
1031	mcspi = spi_master_get_devdata(spi->master);
1032
1033	if (spi->controller_state) {
1034		/* Unlink controller state from context save list */
1035		cs = spi->controller_state;
1036		list_del(&cs->node);
1037
1038		kfree(cs);
1039	}
1040
1041	if (spi->chip_select < spi->master->num_chipselect) {
1042		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1043
1044		if (mcspi_dma->dma_rx) {
1045			dma_release_channel(mcspi_dma->dma_rx);
1046			mcspi_dma->dma_rx = NULL;
1047		}
1048		if (mcspi_dma->dma_tx) {
1049			dma_release_channel(mcspi_dma->dma_tx);
1050			mcspi_dma->dma_tx = NULL;
1051		}
1052	}
1053}
1054
1055static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
1056{
 
 
 
 
 
 
 
 
1057
1058	/* We only enable one channel at a time -- the one whose message is
1059	 * -- although this controller would gladly
1060	 * arbitrate among multiple channels.  This corresponds to "single
1061	 * channel" master mode.  As a side effect, we need to manage the
1062	 * chipselect with the FORCE bit ... CS != channel enable.
1063	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
1064
1065	struct spi_device		*spi;
1066	struct spi_transfer		*t = NULL;
1067	struct spi_master		*master;
1068	struct omap2_mcspi_dma		*mcspi_dma;
1069	int				cs_active = 0;
1070	struct omap2_mcspi_cs		*cs;
1071	struct omap2_mcspi_device_config *cd;
1072	int				par_override = 0;
1073	int				status = 0;
1074	u32				chconf;
1075
1076	spi = m->spi;
1077	master = spi->master;
1078	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1079	cs = spi->controller_state;
1080	cd = spi->controller_data;
1081
1082	omap2_mcspi_set_enable(spi, 0);
1083	list_for_each_entry(t, &m->transfers, transfer_list) {
1084		if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
1085			status = -EINVAL;
1086			break;
1087		}
1088		if (par_override ||
1089		    (t->speed_hz != spi->max_speed_hz) ||
1090		    (t->bits_per_word != spi->bits_per_word)) {
1091			par_override = 1;
1092			status = omap2_mcspi_setup_transfer(spi, t);
1093			if (status < 0)
1094				break;
1095			if (t->speed_hz == spi->max_speed_hz &&
1096			    t->bits_per_word == spi->bits_per_word)
1097				par_override = 0;
1098		}
1099		if (cd && cd->cs_per_word) {
1100			chconf = mcspi->ctx.modulctrl;
1101			chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1102			mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1103			mcspi->ctx.modulctrl =
1104				mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1105		}
1106
 
 
 
 
1107
1108		if (!cs_active) {
1109			omap2_mcspi_force_cs(spi, 1);
1110			cs_active = 1;
1111		}
1112
1113		chconf = mcspi_cached_chconf0(spi);
1114		chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1115		chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1116
1117		if (t->tx_buf == NULL)
1118			chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1119		else if (t->rx_buf == NULL)
1120			chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1121
1122		if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1123			/* Turbo mode is for more than one word */
1124			if (t->len > ((cs->word_len + 7) >> 3))
1125				chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1126		}
1127
1128		mcspi_write_chconf0(spi, chconf);
1129
1130		if (t->len) {
1131			unsigned	count;
1132
1133			if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1134			    (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1135				omap2_mcspi_set_fifo(spi, t, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
1136
1137			omap2_mcspi_set_enable(spi, 1);
 
1138
1139			/* RX_ONLY mode needs dummy data in TX reg */
1140			if (t->tx_buf == NULL)
1141				writel_relaxed(0, cs->base
1142						+ OMAP2_MCSPI_TX0);
1143
1144			if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1145			    (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1146				count = omap2_mcspi_txrx_dma(spi, t);
1147			else
1148				count = omap2_mcspi_txrx_pio(spi, t);
1149			m->actual_length += count;
1150
1151			if (count != t->len) {
1152				status = -EIO;
1153				break;
1154			}
1155		}
1156
1157		if (t->delay_usecs)
1158			udelay(t->delay_usecs);
 
 
 
1159
1160		/* ignore the "leave it on after last xfer" hint */
1161		if (t->cs_change) {
1162			omap2_mcspi_force_cs(spi, 0);
1163			cs_active = 0;
1164		}
1165
1166		omap2_mcspi_set_enable(spi, 0);
1167
1168		if (mcspi->fifo_depth > 0)
1169			omap2_mcspi_set_fifo(spi, t, 0);
1170	}
1171	/* Restore defaults if they were overriden */
1172	if (par_override) {
1173		par_override = 0;
1174		status = omap2_mcspi_setup_transfer(spi, NULL);
1175	}
1176
1177	if (cs_active)
1178		omap2_mcspi_force_cs(spi, 0);
1179
1180	if (cd && cd->cs_per_word) {
1181		chconf = mcspi->ctx.modulctrl;
1182		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1183		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1184		mcspi->ctx.modulctrl =
1185			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1186	}
1187
1188	omap2_mcspi_set_enable(spi, 0);
1189
1190	if (mcspi->fifo_depth > 0 && t)
1191		omap2_mcspi_set_fifo(spi, t, 0);
1192
1193	m->status = status;
1194}
1195
1196static int omap2_mcspi_transfer_one_message(struct spi_master *master,
1197		struct spi_message *m)
1198{
1199	struct spi_device	*spi;
1200	struct omap2_mcspi	*mcspi;
1201	struct omap2_mcspi_dma	*mcspi_dma;
1202	struct spi_transfer	*t;
1203
1204	spi = m->spi;
1205	mcspi = spi_master_get_devdata(master);
1206	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1207	m->actual_length = 0;
1208	m->status = 0;
1209
 
 
 
1210	list_for_each_entry(t, &m->transfers, transfer_list) {
1211		const void	*tx_buf = t->tx_buf;
1212		void		*rx_buf = t->rx_buf;
1213		unsigned	len = t->len;
1214
1215		if ((len && !(rx_buf || tx_buf))) {
1216			dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
 
 
 
 
1217					t->speed_hz,
1218					len,
1219					tx_buf ? "tx" : "",
1220					rx_buf ? "rx" : "",
1221					t->bits_per_word);
1222			return -EINVAL;
1223		}
 
 
 
 
 
 
1224
1225		if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1226			continue;
1227
1228		if (mcspi_dma->dma_tx && tx_buf != NULL) {
1229			t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1230					len, DMA_TO_DEVICE);
1231			if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1232				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1233						'T', len);
1234				return -EINVAL;
1235			}
1236		}
1237		if (mcspi_dma->dma_rx && rx_buf != NULL) {
1238			t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1239					DMA_FROM_DEVICE);
1240			if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1241				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1242						'R', len);
1243				if (tx_buf != NULL)
1244					dma_unmap_single(mcspi->dev, t->tx_dma,
1245							len, DMA_TO_DEVICE);
1246				return -EINVAL;
1247			}
1248		}
1249	}
1250
1251	omap2_mcspi_work(mcspi, m);
1252	spi_finalize_current_message(master);
 
 
 
 
 
1253	return 0;
1254}
1255
1256static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1257{
1258	struct spi_master	*master = mcspi->master;
1259	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1260	int			ret = 0;
1261
1262	ret = pm_runtime_get_sync(mcspi->dev);
1263	if (ret < 0)
1264		return ret;
1265
1266	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1267			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1268	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1269
1270	omap2_mcspi_set_master_mode(master);
1271	pm_runtime_mark_last_busy(mcspi->dev);
1272	pm_runtime_put_autosuspend(mcspi->dev);
1273	return 0;
1274}
1275
1276static int omap_mcspi_runtime_resume(struct device *dev)
1277{
1278	struct omap2_mcspi	*mcspi;
1279	struct spi_master	*master;
1280
1281	master = dev_get_drvdata(dev);
1282	mcspi = spi_master_get_devdata(master);
1283	omap2_mcspi_restore_ctx(mcspi);
1284
1285	return 0;
1286}
1287
1288static struct omap2_mcspi_platform_config omap2_pdata = {
1289	.regs_offset = 0,
1290};
1291
1292static struct omap2_mcspi_platform_config omap4_pdata = {
1293	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1294};
1295
1296static const struct of_device_id omap_mcspi_of_match[] = {
1297	{
1298		.compatible = "ti,omap2-mcspi",
1299		.data = &omap2_pdata,
1300	},
1301	{
1302		.compatible = "ti,omap4-mcspi",
1303		.data = &omap4_pdata,
1304	},
1305	{ },
1306};
1307MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1308
1309static int omap2_mcspi_probe(struct platform_device *pdev)
1310{
1311	struct spi_master	*master;
1312	const struct omap2_mcspi_platform_config *pdata;
1313	struct omap2_mcspi	*mcspi;
1314	struct resource		*r;
1315	int			status = 0, i;
1316	u32			regs_offset = 0;
1317	static int		bus_num = 1;
1318	struct device_node	*node = pdev->dev.of_node;
1319	const struct of_device_id *match;
1320
1321	master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1322	if (master == NULL) {
1323		dev_dbg(&pdev->dev, "master allocation failed\n");
1324		return -ENOMEM;
1325	}
1326
1327	/* the spi->mode bits understood by this driver: */
1328	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1329	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
 
 
 
1330	master->setup = omap2_mcspi_setup;
1331	master->auto_runtime_pm = true;
1332	master->transfer_one_message = omap2_mcspi_transfer_one_message;
1333	master->cleanup = omap2_mcspi_cleanup;
1334	master->dev.of_node = node;
1335	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1336	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1337
1338	platform_set_drvdata(pdev, master);
1339
1340	mcspi = spi_master_get_devdata(master);
1341	mcspi->master = master;
1342
1343	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1344	if (match) {
1345		u32 num_cs = 1; /* default number of chipselect */
1346		pdata = match->data;
1347
1348		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1349		master->num_chipselect = num_cs;
1350		master->bus_num = bus_num++;
1351		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1352			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1353	} else {
1354		pdata = dev_get_platdata(&pdev->dev);
1355		master->num_chipselect = pdata->num_cs;
1356		if (pdev->id != -1)
1357			master->bus_num = pdev->id;
1358		mcspi->pin_dir = pdata->pin_dir;
1359	}
1360	regs_offset = pdata->regs_offset;
1361
1362	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1363	if (r == NULL) {
1364		status = -ENODEV;
1365		goto free_master;
 
 
 
 
 
1366	}
1367
1368	r->start += regs_offset;
1369	r->end += regs_offset;
1370	mcspi->phys = r->start;
1371
1372	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1373	if (IS_ERR(mcspi->base)) {
1374		status = PTR_ERR(mcspi->base);
1375		goto free_master;
1376	}
1377
1378	mcspi->dev = &pdev->dev;
 
1379
1380	INIT_LIST_HEAD(&mcspi->ctx.cs);
 
 
 
 
 
 
1381
1382	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1383					   sizeof(struct omap2_mcspi_dma),
1384					   GFP_KERNEL);
1385	if (mcspi->dma_channels == NULL) {
1386		status = -ENOMEM;
1387		goto free_master;
1388	}
1389
1390	for (i = 0; i < master->num_chipselect; i++) {
1391		char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1392		char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1393		struct resource *dma_res;
1394
1395		sprintf(dma_rx_ch_name, "rx%d", i);
1396		if (!pdev->dev.of_node) {
1397			dma_res =
1398				platform_get_resource_byname(pdev,
1399							     IORESOURCE_DMA,
1400							     dma_rx_ch_name);
1401			if (!dma_res) {
1402				dev_dbg(&pdev->dev,
1403					"cannot get DMA RX channel\n");
1404				status = -ENODEV;
1405				break;
1406			}
1407
1408			mcspi->dma_channels[i].dma_rx_sync_dev =
1409				dma_res->start;
 
 
 
 
 
 
 
1410		}
1411		sprintf(dma_tx_ch_name, "tx%d", i);
1412		if (!pdev->dev.of_node) {
1413			dma_res =
1414				platform_get_resource_byname(pdev,
1415							     IORESOURCE_DMA,
1416							     dma_tx_ch_name);
1417			if (!dma_res) {
1418				dev_dbg(&pdev->dev,
1419					"cannot get DMA TX channel\n");
1420				status = -ENODEV;
1421				break;
1422			}
1423
1424			mcspi->dma_channels[i].dma_tx_sync_dev =
1425				dma_res->start;
1426		}
1427	}
1428
1429	if (status < 0)
1430		goto free_master;
1431
1432	pm_runtime_use_autosuspend(&pdev->dev);
1433	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1434	pm_runtime_enable(&pdev->dev);
1435
1436	status = omap2_mcspi_master_setup(mcspi);
1437	if (status < 0)
1438		goto disable_pm;
1439
1440	status = devm_spi_register_master(&pdev->dev, master);
1441	if (status < 0)
1442		goto disable_pm;
1443
1444	return status;
1445
1446disable_pm:
1447	pm_runtime_disable(&pdev->dev);
1448free_master:
1449	spi_master_put(master);
 
 
 
 
 
 
1450	return status;
1451}
1452
1453static int omap2_mcspi_remove(struct platform_device *pdev)
1454{
1455	struct spi_master *master = platform_get_drvdata(pdev);
1456	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 
 
 
 
 
 
 
 
 
 
 
1457
1458	pm_runtime_put_sync(mcspi->dev);
1459	pm_runtime_disable(&pdev->dev);
 
 
1460
1461	return 0;
1462}
1463
1464/* work with hotplug and coldplug */
1465MODULE_ALIAS("platform:omap2_mcspi");
1466
1467#ifdef	CONFIG_SUSPEND
1468/*
1469 * When SPI wake up from off-mode, CS is in activate state. If it was in
1470 * unactive state when driver was suspend, then force it to unactive state at
1471 * wake up.
1472 */
1473static int omap2_mcspi_resume(struct device *dev)
1474{
1475	struct spi_master	*master = dev_get_drvdata(dev);
1476	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1477	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1478	struct omap2_mcspi_cs	*cs;
1479
1480	pm_runtime_get_sync(mcspi->dev);
1481	list_for_each_entry(cs, &ctx->cs, node) {
 
1482		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
 
1483			/*
1484			 * We need to toggle CS state for OMAP take this
1485			 * change in account.
1486			 */
1487			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1488			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1489			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1490			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1491		}
1492	}
1493	pm_runtime_mark_last_busy(mcspi->dev);
1494	pm_runtime_put_autosuspend(mcspi->dev);
1495	return 0;
1496}
1497#else
1498#define	omap2_mcspi_resume	NULL
1499#endif
1500
1501static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1502	.resume = omap2_mcspi_resume,
1503	.runtime_resume	= omap_mcspi_runtime_resume,
1504};
1505
1506static struct platform_driver omap2_mcspi_driver = {
1507	.driver = {
1508		.name =		"omap2_mcspi",
1509		.owner =	THIS_MODULE,
1510		.pm =		&omap2_mcspi_pm_ops,
1511		.of_match_table = omap_mcspi_of_match,
1512	},
1513	.probe =	omap2_mcspi_probe,
1514	.remove =	omap2_mcspi_remove,
1515};
1516
1517module_platform_driver(omap2_mcspi_driver);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1518MODULE_LICENSE("GPL");