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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");
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");