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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");
v5.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * OMAP2 McSPI controller driver
   4 *
   5 * Copyright (C) 2005, 2006 Nokia Corporation
   6 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   7 *		Juha Yrj�l� <juha.yrjola@nokia.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   8 */
   9
  10#include <linux/kernel.h>
 
  11#include <linux/interrupt.h>
  12#include <linux/module.h>
  13#include <linux/device.h>
  14#include <linux/delay.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/dmaengine.h>
  17#include <linux/pinctrl/consumer.h>
  18#include <linux/platform_device.h>
  19#include <linux/err.h>
  20#include <linux/clk.h>
  21#include <linux/io.h>
  22#include <linux/slab.h>
  23#include <linux/pm_runtime.h>
  24#include <linux/of.h>
  25#include <linux/of_device.h>
  26#include <linux/gcd.h>
  27#include <linux/iopoll.h>
  28
  29#include <linux/spi/spi.h>
  30#include <linux/gpio.h>
  31
  32#include <linux/platform_data/spi-omap2-mcspi.h>
 
 
  33
  34#define OMAP2_MCSPI_MAX_FREQ		48000000
  35#define OMAP2_MCSPI_MAX_DIVIDER		4096
  36#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  37#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  38#define SPI_AUTOSUSPEND_TIMEOUT		2000
  39
  40#define OMAP2_MCSPI_REVISION		0x00
  41#define OMAP2_MCSPI_SYSSTATUS		0x14
  42#define OMAP2_MCSPI_IRQSTATUS		0x18
  43#define OMAP2_MCSPI_IRQENABLE		0x1c
  44#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  45#define OMAP2_MCSPI_SYST		0x24
  46#define OMAP2_MCSPI_MODULCTRL		0x28
  47#define OMAP2_MCSPI_XFERLEVEL		0x7c
  48
  49/* per-channel banks, 0x14 bytes each, first is: */
  50#define OMAP2_MCSPI_CHCONF0		0x2c
  51#define OMAP2_MCSPI_CHSTAT0		0x30
  52#define OMAP2_MCSPI_CHCTRL0		0x34
  53#define OMAP2_MCSPI_TX0			0x38
  54#define OMAP2_MCSPI_RX0			0x3c
  55
  56/* per-register bitmasks: */
  57#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  58
  59#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  60#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  61#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  62
  63#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  64#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  65#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  66#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  67#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  68#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  69#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  70#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  71#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  72#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  73#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  74#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  75#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  76#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  77#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  78#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  79#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  80#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  81
  82#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  83#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  84#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  85#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  86
  87#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
  88#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
  89
  90#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  91
  92/* We have 2 DMA channels per CS, one for RX and one for TX */
  93struct omap2_mcspi_dma {
  94	struct dma_chan *dma_tx;
  95	struct dma_chan *dma_rx;
 
 
 
  96
  97	struct completion dma_tx_completion;
  98	struct completion dma_rx_completion;
  99
 100	char dma_rx_ch_name[14];
 101	char dma_tx_ch_name[14];
 102};
 103
 104/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 105 * cache operations; better heuristics consider wordsize and bitrate.
 106 */
 107#define DMA_MIN_BYTES			160
 108
 109
 110/*
 111 * Used for context save and restore, structure members to be updated whenever
 112 * corresponding registers are modified.
 113 */
 114struct omap2_mcspi_regs {
 115	u32 modulctrl;
 116	u32 wakeupenable;
 117	struct list_head cs;
 118};
 119
 120struct omap2_mcspi {
 121	struct completion	txdone;
 
 
 
 122	struct spi_master	*master;
 123	/* Virtual base address of the controller */
 124	void __iomem		*base;
 125	unsigned long		phys;
 126	/* SPI1 has 4 channels, while SPI2 has 2 */
 127	struct omap2_mcspi_dma	*dma_channels;
 128	struct device		*dev;
 129	struct omap2_mcspi_regs ctx;
 130	int			fifo_depth;
 131	bool			slave_aborted;
 132	unsigned int		pin_dir:1;
 133};
 134
 135struct omap2_mcspi_cs {
 136	void __iomem		*base;
 137	unsigned long		phys;
 138	int			word_len;
 139	u16			mode;
 140	struct list_head	node;
 141	/* Context save and restore shadow register */
 142	u32			chconf0, chctrl0;
 
 
 
 
 
 
 
 
 
 143};
 144
 
 
 
 
 
 
 
 
 
 
 
 145static inline void mcspi_write_reg(struct spi_master *master,
 146		int idx, u32 val)
 147{
 148	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 149
 150	writel_relaxed(val, mcspi->base + idx);
 151}
 152
 153static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 154{
 155	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 156
 157	return readl_relaxed(mcspi->base + idx);
 158}
 159
 160static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 161		int idx, u32 val)
 162{
 163	struct omap2_mcspi_cs	*cs = spi->controller_state;
 164
 165	writel_relaxed(val, cs->base +  idx);
 166}
 167
 168static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 169{
 170	struct omap2_mcspi_cs	*cs = spi->controller_state;
 171
 172	return readl_relaxed(cs->base + idx);
 173}
 174
 175static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 176{
 177	struct omap2_mcspi_cs *cs = spi->controller_state;
 178
 179	return cs->chconf0;
 180}
 181
 182static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 183{
 184	struct omap2_mcspi_cs *cs = spi->controller_state;
 185
 186	cs->chconf0 = val;
 187	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 188	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 189}
 190
 191static inline int mcspi_bytes_per_word(int word_len)
 192{
 193	if (word_len <= 8)
 194		return 1;
 195	else if (word_len <= 16)
 196		return 2;
 197	else /* word_len <= 32 */
 198		return 4;
 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	if (enable)
 214		l |= rw;
 215	else
 216		l &= ~rw;
 217
 218	mcspi_write_chconf0(spi, l);
 219}
 220
 221static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 222{
 223	struct omap2_mcspi_cs *cs = spi->controller_state;
 224	u32 l;
 225
 226	l = cs->chctrl0;
 227	if (enable)
 228		l |= OMAP2_MCSPI_CHCTRL_EN;
 229	else
 230		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 231	cs->chctrl0 = l;
 232	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 233	/* Flash post-writes */
 234	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 235}
 236
 237static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 238{
 239	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 240	u32 l;
 241
 242	/* The controller handles the inverted chip selects
 243	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 244	 * the inversion from the core spi_set_cs function.
 245	 */
 246	if (spi->mode & SPI_CS_HIGH)
 247		enable = !enable;
 248
 249	if (spi->controller_state) {
 250		int err = pm_runtime_get_sync(mcspi->dev);
 251		if (err < 0) {
 252			pm_runtime_put_noidle(mcspi->dev);
 253			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 254			return;
 255		}
 256
 257		l = mcspi_cached_chconf0(spi);
 258
 259		if (enable)
 260			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 261		else
 262			l |= OMAP2_MCSPI_CHCONF_FORCE;
 263
 264		mcspi_write_chconf0(spi, l);
 265
 266		pm_runtime_mark_last_busy(mcspi->dev);
 267		pm_runtime_put_autosuspend(mcspi->dev);
 268	}
 269}
 270
 271static void omap2_mcspi_set_mode(struct spi_master *master)
 272{
 273	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 274	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 275	u32 l;
 276
 277	/*
 278	 * Choose master or slave mode
 279	 */
 280	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 281	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
 282	if (spi_controller_is_slave(master)) {
 283		l |= (OMAP2_MCSPI_MODULCTRL_MS);
 284	} else {
 285		l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
 286		l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 287	}
 288	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 289
 290	ctx->modulctrl = l;
 291}
 292
 293static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 294				struct spi_transfer *t, int enable)
 295{
 296	struct spi_master *master = spi->master;
 297	struct omap2_mcspi_cs *cs = spi->controller_state;
 298	struct omap2_mcspi *mcspi;
 299	unsigned int wcnt;
 300	int max_fifo_depth, bytes_per_word;
 301	u32 chconf, xferlevel;
 302
 303	mcspi = spi_master_get_devdata(master);
 304
 305	chconf = mcspi_cached_chconf0(spi);
 306	if (enable) {
 307		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 308		if (t->len % bytes_per_word != 0)
 309			goto disable_fifo;
 310
 311		if (t->rx_buf != NULL && t->tx_buf != NULL)
 312			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 313		else
 314			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 315
 316		wcnt = t->len / bytes_per_word;
 317		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 318			goto disable_fifo;
 319
 320		xferlevel = wcnt << 16;
 321		if (t->rx_buf != NULL) {
 322			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 323			xferlevel |= (bytes_per_word - 1) << 8;
 324		}
 325
 326		if (t->tx_buf != NULL) {
 327			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 328			xferlevel |= bytes_per_word - 1;
 329		}
 330
 331		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 332		mcspi_write_chconf0(spi, chconf);
 333		mcspi->fifo_depth = max_fifo_depth;
 334
 335		return;
 336	}
 337
 338disable_fifo:
 339	if (t->rx_buf != NULL)
 340		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 341
 342	if (t->tx_buf != NULL)
 343		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 344
 345	mcspi_write_chconf0(spi, chconf);
 346	mcspi->fifo_depth = 0;
 347}
 348
 349static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 350{
 351	u32 val;
 352
 353	return readl_poll_timeout(reg, val, val & bit, 1, MSEC_PER_SEC);
 354}
 355
 356static int mcspi_wait_for_completion(struct  omap2_mcspi *mcspi,
 357				     struct completion *x)
 358{
 359	if (spi_controller_is_slave(mcspi->master)) {
 360		if (wait_for_completion_interruptible(x) ||
 361		    mcspi->slave_aborted)
 362			return -EINTR;
 363	} else {
 364		wait_for_completion(x);
 365	}
 366
 367	return 0;
 368}
 369
 370static void omap2_mcspi_rx_callback(void *data)
 371{
 372	struct spi_device *spi = data;
 373	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 374	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 375
 376	/* We must disable the DMA RX request */
 377	omap2_mcspi_set_dma_req(spi, 1, 0);
 378
 379	complete(&mcspi_dma->dma_rx_completion);
 380}
 381
 382static void omap2_mcspi_tx_callback(void *data)
 383{
 384	struct spi_device *spi = data;
 385	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 386	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 387
 388	/* We must disable the DMA TX request */
 389	omap2_mcspi_set_dma_req(spi, 0, 0);
 390
 391	complete(&mcspi_dma->dma_tx_completion);
 392}
 393
 394static void omap2_mcspi_tx_dma(struct spi_device *spi,
 395				struct spi_transfer *xfer,
 396				struct dma_slave_config cfg)
 397{
 398	struct omap2_mcspi	*mcspi;
 399	struct omap2_mcspi_dma  *mcspi_dma;
 400
 401	mcspi = spi_master_get_devdata(spi->master);
 402	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 403
 404	if (mcspi_dma->dma_tx) {
 405		struct dma_async_tx_descriptor *tx;
 406
 407		dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 408
 409		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 410					     xfer->tx_sg.nents,
 411					     DMA_MEM_TO_DEV,
 412					     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 413		if (tx) {
 414			tx->callback = omap2_mcspi_tx_callback;
 415			tx->callback_param = spi;
 416			dmaengine_submit(tx);
 417		} else {
 418			/* FIXME: fall back to PIO? */
 419		}
 420	}
 421	dma_async_issue_pending(mcspi_dma->dma_tx);
 422	omap2_mcspi_set_dma_req(spi, 0, 1);
 423
 424}
 425
 426static unsigned
 427omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 428				struct dma_slave_config cfg,
 429				unsigned es)
 430{
 431	struct omap2_mcspi	*mcspi;
 
 432	struct omap2_mcspi_dma  *mcspi_dma;
 433	unsigned int		count, transfer_reduction = 0;
 434	struct scatterlist	*sg_out[2];
 435	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 436	size_t			sizes[2];
 437	u32			l;
 438	int			elements = 0;
 439	int			word_len, element_count;
 440	struct omap2_mcspi_cs	*cs = spi->controller_state;
 441	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 442
 443	mcspi = spi_master_get_devdata(spi->master);
 444	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 445	count = xfer->len;
 446
 447	/*
 448	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 449	 *  it mentions reducing DMA transfer length by one element in master
 450	 *  normal mode.
 451	 */
 452	if (mcspi->fifo_depth == 0)
 453		transfer_reduction = es;
 454
 
 
 455	word_len = cs->word_len;
 456	l = mcspi_cached_chconf0(spi);
 457
 458	if (word_len <= 8)
 
 
 
 
 
 
 
 459		element_count = count;
 460	else if (word_len <= 16)
 
 461		element_count = count >> 1;
 462	else /* word_len <= 32 */
 
 463		element_count = count >> 2;
 
 464
 465	if (mcspi_dma->dma_rx) {
 466		struct dma_async_tx_descriptor *tx;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 467
 468		dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 
 
 
 469
 470		/*
 471		 *  Reduce DMA transfer length by one more if McSPI is
 472		 *  configured in turbo mode.
 473		 */
 474		if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 475			transfer_reduction += es;
 476
 477		if (transfer_reduction) {
 478			/* Split sgl into two. The second sgl won't be used. */
 479			sizes[0] = count - transfer_reduction;
 480			sizes[1] = transfer_reduction;
 481			nb_sizes = 2;
 482		} else {
 483			/*
 484			 * Don't bother splitting the sgl. This essentially
 485			 * clones the original sgl.
 486			 */
 487			sizes[0] = count;
 488			nb_sizes = 1;
 489		}
 490
 491		ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents,
 492			       0, nb_sizes,
 493			       sizes,
 494			       sg_out, out_mapped_nents,
 495			       GFP_KERNEL);
 496
 497		if (ret < 0) {
 498			dev_err(&spi->dev, "sg_split failed\n");
 499			return 0;
 500		}
 501
 502		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx,
 503					     sg_out[0],
 504					     out_mapped_nents[0],
 505					     DMA_DEV_TO_MEM,
 506					     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 507		if (tx) {
 508			tx->callback = omap2_mcspi_rx_callback;
 509			tx->callback_param = spi;
 510			dmaengine_submit(tx);
 511		} else {
 512				/* FIXME: fall back to PIO? */
 513		}
 514	}
 515
 516	dma_async_issue_pending(mcspi_dma->dma_rx);
 517	omap2_mcspi_set_dma_req(spi, 1, 1);
 
 
 518
 519	ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
 520	if (ret || mcspi->slave_aborted) {
 521		dmaengine_terminate_sync(mcspi_dma->dma_rx);
 522		omap2_mcspi_set_dma_req(spi, 1, 0);
 523		return 0;
 524	}
 525
 526	for (x = 0; x < nb_sizes; x++)
 527		kfree(sg_out[x]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 528
 529	if (mcspi->fifo_depth > 0)
 530		return count;
 531
 532	/*
 533	 *  Due to the DMA transfer length reduction the missing bytes must
 534	 *  be read manually to receive all of the expected data.
 535	 */
 536	omap2_mcspi_set_enable(spi, 0);
 537
 538	elements = element_count - 1;
 539
 540	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 541		elements--;
 542
 543		if (!mcspi_wait_for_reg_bit(chstat_reg,
 544					    OMAP2_MCSPI_CHSTAT_RXS)) {
 545			u32 w;
 546
 547			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 548			if (word_len <= 8)
 549				((u8 *)xfer->rx_buf)[elements++] = w;
 550			else if (word_len <= 16)
 551				((u16 *)xfer->rx_buf)[elements++] = w;
 552			else /* word_len <= 32 */
 553				((u32 *)xfer->rx_buf)[elements++] = w;
 554		} else {
 555			int bytes_per_word = mcspi_bytes_per_word(word_len);
 556			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 557			count -= (bytes_per_word << 1);
 558			omap2_mcspi_set_enable(spi, 1);
 559			return count;
 560		}
 
 561	}
 562	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 563		u32 w;
 564
 565		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 566		if (word_len <= 8)
 567			((u8 *)xfer->rx_buf)[elements] = w;
 568		else if (word_len <= 16)
 569			((u16 *)xfer->rx_buf)[elements] = w;
 570		else /* word_len <= 32 */
 571			((u32 *)xfer->rx_buf)[elements] = w;
 572	} else {
 573		dev_err(&spi->dev, "DMA RX last word empty\n");
 574		count -= mcspi_bytes_per_word(word_len);
 575	}
 576	omap2_mcspi_set_enable(spi, 1);
 577	return count;
 578}
 579
 580static unsigned
 581omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 582{
 583	struct omap2_mcspi	*mcspi;
 584	struct omap2_mcspi_cs	*cs = spi->controller_state;
 585	struct omap2_mcspi_dma  *mcspi_dma;
 586	unsigned int		count;
 587	u8			*rx;
 588	const u8		*tx;
 589	struct dma_slave_config	cfg;
 590	enum dma_slave_buswidth width;
 591	unsigned es;
 592	void __iomem		*chstat_reg;
 593	void __iomem            *irqstat_reg;
 594	int			wait_res;
 595
 596	mcspi = spi_master_get_devdata(spi->master);
 597	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 598
 599	if (cs->word_len <= 8) {
 600		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 601		es = 1;
 602	} else if (cs->word_len <= 16) {
 603		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 604		es = 2;
 605	} else {
 606		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 607		es = 4;
 608	}
 609
 610	count = xfer->len;
 611
 612	memset(&cfg, 0, sizeof(cfg));
 613	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 614	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 615	cfg.src_addr_width = width;
 616	cfg.dst_addr_width = width;
 617	cfg.src_maxburst = 1;
 618	cfg.dst_maxburst = 1;
 619
 620	rx = xfer->rx_buf;
 621	tx = xfer->tx_buf;
 622
 623	mcspi->slave_aborted = false;
 624	reinit_completion(&mcspi_dma->dma_tx_completion);
 625	reinit_completion(&mcspi_dma->dma_rx_completion);
 626	reinit_completion(&mcspi->txdone);
 627	if (tx) {
 628		/* Enable EOW IRQ to know end of tx in slave mode */
 629		if (spi_controller_is_slave(spi->master))
 630			mcspi_write_reg(spi->master,
 631					OMAP2_MCSPI_IRQENABLE,
 632					OMAP2_MCSPI_IRQSTATUS_EOW);
 633		omap2_mcspi_tx_dma(spi, xfer, cfg);
 634	}
 635
 636	if (rx != NULL)
 637		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 638
 639	if (tx != NULL) {
 640		int ret;
 641
 642		ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
 643		if (ret || mcspi->slave_aborted) {
 644			dmaengine_terminate_sync(mcspi_dma->dma_tx);
 645			omap2_mcspi_set_dma_req(spi, 0, 0);
 646			return 0;
 647		}
 648
 649		if (spi_controller_is_slave(mcspi->master)) {
 650			ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
 651			if (ret || mcspi->slave_aborted)
 652				return 0;
 653		}
 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_cs	*cs = spi->controller_state;
 693	unsigned int		count, c;
 694	u32			l;
 695	void __iomem		*base = cs->base;
 696	void __iomem		*tx_reg;
 697	void __iomem		*rx_reg;
 698	void __iomem		*chstat_reg;
 699	int			word_len;
 700
 
 701	count = xfer->len;
 702	c = count;
 703	word_len = cs->word_len;
 704
 705	l = mcspi_cached_chconf0(spi);
 706
 707	/* We store the pre-calculated register addresses on stack to speed
 708	 * up the transfer loop. */
 709	tx_reg		= base + OMAP2_MCSPI_TX0;
 710	rx_reg		= base + OMAP2_MCSPI_RX0;
 711	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 712
 713	if (c < (word_len>>3))
 714		return 0;
 715
 716	if (word_len <= 8) {
 717		u8		*rx;
 718		const u8	*tx;
 719
 720		rx = xfer->rx_buf;
 721		tx = xfer->tx_buf;
 722
 723		do {
 724			c -= 1;
 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 %02x\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 == 1 && 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 %02x\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 %02x\n",
 761						word_len, *(rx - 1));
 762			}
 763		} while (c);
 764	} else if (word_len <= 16) {
 765		u16		*rx;
 766		const u16	*tx;
 767
 768		rx = xfer->rx_buf;
 769		tx = xfer->tx_buf;
 770		do {
 771			c -= 2;
 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 %04x\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 == 2 && 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 %04x\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 %04x\n",
 808						word_len, *(rx - 1));
 809			}
 810		} while (c >= 2);
 811	} else if (word_len <= 32) {
 812		u32		*rx;
 813		const u32	*tx;
 814
 815		rx = xfer->rx_buf;
 816		tx = xfer->tx_buf;
 817		do {
 818			c -= 4;
 819			if (tx != NULL) {
 820				if (mcspi_wait_for_reg_bit(chstat_reg,
 821						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 822					dev_err(&spi->dev, "TXS timed out\n");
 823					goto out;
 824				}
 825				dev_vdbg(&spi->dev, "write-%d %08x\n",
 826						word_len, *tx);
 827				writel_relaxed(*tx++, tx_reg);
 828			}
 829			if (rx != NULL) {
 830				if (mcspi_wait_for_reg_bit(chstat_reg,
 831						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 832					dev_err(&spi->dev, "RXS timed out\n");
 833					goto out;
 834				}
 835
 836				if (c == 4 && tx == NULL &&
 837				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 838					omap2_mcspi_set_enable(spi, 0);
 839					*rx++ = readl_relaxed(rx_reg);
 840					dev_vdbg(&spi->dev, "read-%d %08x\n",
 841						    word_len, *(rx - 1));
 842					if (mcspi_wait_for_reg_bit(chstat_reg,
 843						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 844						dev_err(&spi->dev,
 845							"RXS timed out\n");
 846						goto out;
 847					}
 848					c = 0;
 849				} else if (c == 0 && tx == NULL) {
 850					omap2_mcspi_set_enable(spi, 0);
 851				}
 852
 853				*rx++ = readl_relaxed(rx_reg);
 854				dev_vdbg(&spi->dev, "read-%d %08x\n",
 855						word_len, *(rx - 1));
 856			}
 857		} while (c >= 4);
 858	}
 859
 860	/* for TX_ONLY mode, be sure all words have shifted out */
 861	if (xfer->rx_buf == NULL) {
 862		if (mcspi_wait_for_reg_bit(chstat_reg,
 863				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 864			dev_err(&spi->dev, "TXS timed out\n");
 865		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 866				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 867			dev_err(&spi->dev, "EOT timed out\n");
 868
 869		/* disable chan to purge rx datas received in TX_ONLY transfer,
 870		 * otherwise these rx datas will affect the direct following
 871		 * RX_ONLY transfer.
 872		 */
 873		omap2_mcspi_set_enable(spi, 0);
 874	}
 875out:
 876	omap2_mcspi_set_enable(spi, 1);
 877	return count - c;
 878}
 879
 880static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 881{
 882	u32 div;
 883
 884	for (div = 0; div < 15; div++)
 885		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 886			return div;
 887
 888	return 15;
 889}
 890
 891/* called only when no transfer is active to this device */
 892static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 893		struct spi_transfer *t)
 894{
 895	struct omap2_mcspi_cs *cs = spi->controller_state;
 896	struct omap2_mcspi *mcspi;
 897	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 
 898	u8 word_len = spi->bits_per_word;
 899	u32 speed_hz = spi->max_speed_hz;
 900
 901	mcspi = spi_master_get_devdata(spi->master);
 
 902
 903	if (t != NULL && t->bits_per_word)
 904		word_len = t->bits_per_word;
 905
 906	cs->word_len = word_len;
 907
 908	if (t && t->speed_hz)
 909		speed_hz = t->speed_hz;
 910
 911	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 912	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 913		clkd = omap2_mcspi_calc_divisor(speed_hz);
 914		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 915		clkg = 0;
 916	} else {
 917		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 918		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 919		clkd = (div - 1) & 0xf;
 920		extclk = (div - 1) >> 4;
 921		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 922	}
 923
 924	l = mcspi_cached_chconf0(spi);
 925
 926	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 927	 * REVISIT: this controller could support SPI_3WIRE mode.
 928	 */
 929	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 930		l &= ~OMAP2_MCSPI_CHCONF_IS;
 931		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 932		l |= OMAP2_MCSPI_CHCONF_DPE0;
 933	} else {
 934		l |= OMAP2_MCSPI_CHCONF_IS;
 935		l |= OMAP2_MCSPI_CHCONF_DPE1;
 936		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 937	}
 938
 939	/* wordlength */
 940	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 941	l |= (word_len - 1) << 7;
 942
 943	/* set chipselect polarity; manage with FORCE */
 944	if (!(spi->mode & SPI_CS_HIGH))
 945		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 946	else
 947		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 948
 949	/* set clock divisor */
 950	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 951	l |= clkd << 2;
 952
 953	/* set clock granularity */
 954	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 955	l |= clkg;
 956	if (clkg) {
 957		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 958		cs->chctrl0 |= extclk << 8;
 959		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 960	}
 961
 962	/* set SPI mode 0..3 */
 963	if (spi->mode & SPI_CPOL)
 964		l |= OMAP2_MCSPI_CHCONF_POL;
 965	else
 966		l &= ~OMAP2_MCSPI_CHCONF_POL;
 967	if (spi->mode & SPI_CPHA)
 968		l |= OMAP2_MCSPI_CHCONF_PHA;
 969	else
 970		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 971
 972	mcspi_write_chconf0(spi, l);
 973
 974	cs->mode = spi->mode;
 975
 976	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 977			speed_hz,
 978			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 979			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 980
 981	return 0;
 982}
 983
 984/*
 985 * Note that we currently allow DMA only if we get a channel
 986 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 987 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 988static int omap2_mcspi_request_dma(struct spi_device *spi)
 989{
 990	struct spi_master	*master = spi->master;
 991	struct omap2_mcspi	*mcspi;
 992	struct omap2_mcspi_dma	*mcspi_dma;
 993	int ret = 0;
 994
 995	mcspi = spi_master_get_devdata(master);
 996	mcspi_dma = mcspi->dma_channels + spi->chip_select;
 997
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 998	init_completion(&mcspi_dma->dma_rx_completion);
 999	init_completion(&mcspi_dma->dma_tx_completion);
1000
1001	mcspi_dma->dma_rx = dma_request_chan(&master->dev,
1002					     mcspi_dma->dma_rx_ch_name);
1003	if (IS_ERR(mcspi_dma->dma_rx)) {
1004		ret = PTR_ERR(mcspi_dma->dma_rx);
1005		mcspi_dma->dma_rx = NULL;
1006		goto no_dma;
1007	}
1008
1009	mcspi_dma->dma_tx = dma_request_chan(&master->dev,
1010					     mcspi_dma->dma_tx_ch_name);
1011	if (IS_ERR(mcspi_dma->dma_tx)) {
1012		ret = PTR_ERR(mcspi_dma->dma_tx);
1013		mcspi_dma->dma_tx = NULL;
1014		dma_release_channel(mcspi_dma->dma_rx);
1015		mcspi_dma->dma_rx = NULL;
1016	}
1017
1018no_dma:
1019	return ret;
1020}
1021
1022static int omap2_mcspi_setup(struct spi_device *spi)
1023{
1024	int			ret;
1025	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
1026	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1027	struct omap2_mcspi_dma	*mcspi_dma;
1028	struct omap2_mcspi_cs	*cs = spi->controller_state;
1029
 
 
 
 
 
 
 
1030	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1031
1032	if (!cs) {
1033		cs = kzalloc(sizeof *cs, GFP_KERNEL);
1034		if (!cs)
1035			return -ENOMEM;
1036		cs->base = mcspi->base + spi->chip_select * 0x14;
1037		cs->phys = mcspi->phys + spi->chip_select * 0x14;
1038		cs->mode = 0;
1039		cs->chconf0 = 0;
1040		cs->chctrl0 = 0;
1041		spi->controller_state = cs;
1042		/* Link this to context save list */
1043		list_add_tail(&cs->node, &ctx->cs);
1044
1045		if (gpio_is_valid(spi->cs_gpio)) {
1046			ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1047			if (ret) {
1048				dev_err(&spi->dev, "failed to request gpio\n");
1049				return ret;
1050			}
1051			gpio_direction_output(spi->cs_gpio,
1052					 !(spi->mode & SPI_CS_HIGH));
1053		}
1054	}
1055
1056	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
 
1057		ret = omap2_mcspi_request_dma(spi);
1058		if (ret)
1059			dev_warn(&spi->dev, "not using DMA for McSPI (%d)\n",
1060				 ret);
1061	}
1062
1063	ret = pm_runtime_get_sync(mcspi->dev);
1064	if (ret < 0) {
1065		pm_runtime_put_noidle(mcspi->dev);
1066
1067		return ret;
1068	}
1069
1070	ret = omap2_mcspi_setup_transfer(spi, NULL);
1071	pm_runtime_mark_last_busy(mcspi->dev);
1072	pm_runtime_put_autosuspend(mcspi->dev);
1073
1074	return ret;
1075}
1076
1077static void omap2_mcspi_cleanup(struct spi_device *spi)
1078{
1079	struct omap2_mcspi	*mcspi;
1080	struct omap2_mcspi_dma	*mcspi_dma;
1081	struct omap2_mcspi_cs	*cs;
1082
1083	mcspi = spi_master_get_devdata(spi->master);
1084
1085	if (spi->controller_state) {
1086		/* Unlink controller state from context save list */
1087		cs = spi->controller_state;
1088		list_del(&cs->node);
1089
1090		kfree(cs);
1091	}
1092
1093	if (spi->chip_select < spi->master->num_chipselect) {
1094		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1095
1096		if (mcspi_dma->dma_rx) {
1097			dma_release_channel(mcspi_dma->dma_rx);
1098			mcspi_dma->dma_rx = NULL;
1099		}
1100		if (mcspi_dma->dma_tx) {
1101			dma_release_channel(mcspi_dma->dma_tx);
1102			mcspi_dma->dma_tx = NULL;
1103		}
1104	}
1105
1106	if (gpio_is_valid(spi->cs_gpio))
1107		gpio_free(spi->cs_gpio);
1108}
1109
1110static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1111{
1112	struct omap2_mcspi *mcspi = data;
1113	u32 irqstat;
1114
1115	irqstat	= mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1116	if (!irqstat)
1117		return IRQ_NONE;
1118
1119	/* Disable IRQ and wakeup slave xfer task */
1120	mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1121	if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1122		complete(&mcspi->txdone);
1123
1124	return IRQ_HANDLED;
1125}
1126
1127static int omap2_mcspi_slave_abort(struct spi_master *master)
1128{
1129	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1130	struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1131
1132	mcspi->slave_aborted = true;
1133	complete(&mcspi_dma->dma_rx_completion);
1134	complete(&mcspi_dma->dma_tx_completion);
1135	complete(&mcspi->txdone);
1136
1137	return 0;
1138}
1139
1140static int omap2_mcspi_transfer_one(struct spi_master *master,
1141				    struct spi_device *spi,
1142				    struct spi_transfer *t)
1143{
1144
1145	/* We only enable one channel at a time -- the one whose message is
1146	 * -- although this controller would gladly
1147	 * arbitrate among multiple channels.  This corresponds to "single
1148	 * channel" master mode.  As a side effect, we need to manage the
1149	 * chipselect with the FORCE bit ... CS != channel enable.
1150	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1151
1152	struct omap2_mcspi		*mcspi;
1153	struct omap2_mcspi_dma		*mcspi_dma;
1154	struct omap2_mcspi_cs		*cs;
1155	struct omap2_mcspi_device_config *cd;
1156	int				par_override = 0;
1157	int				status = 0;
1158	u32				chconf;
1159
1160	mcspi = spi_master_get_devdata(master);
1161	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1162	cs = spi->controller_state;
1163	cd = spi->controller_data;
 
 
 
 
 
 
 
 
 
 
1164
1165	/*
1166	 * The slave driver could have changed spi->mode in which case
1167	 * it will be different from cs->mode (the current hardware setup).
1168	 * If so, set par_override (even though its not a parity issue) so
1169	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1170	 * with the correct mode on the first iteration of the loop below.
1171	 */
1172	if (spi->mode != cs->mode)
1173		par_override = 1;
1174
1175	omap2_mcspi_set_enable(spi, 0);
 
1176
1177	if (gpio_is_valid(spi->cs_gpio))
1178		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1179
1180	if (par_override ||
1181	    (t->speed_hz != spi->max_speed_hz) ||
1182	    (t->bits_per_word != spi->bits_per_word)) {
1183		par_override = 1;
1184		status = omap2_mcspi_setup_transfer(spi, t);
1185		if (status < 0)
1186			goto out;
1187		if (t->speed_hz == spi->max_speed_hz &&
1188		    t->bits_per_word == spi->bits_per_word)
1189			par_override = 0;
1190	}
1191	if (cd && cd->cs_per_word) {
1192		chconf = mcspi->ctx.modulctrl;
1193		chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1194		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1195		mcspi->ctx.modulctrl =
1196			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1197	}
1198
1199	chconf = mcspi_cached_chconf0(spi);
1200	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1201	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1202
1203	if (t->tx_buf == NULL)
1204		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1205	else if (t->rx_buf == NULL)
1206		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1207
1208	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1209		/* Turbo mode is for more than one word */
1210		if (t->len > ((cs->word_len + 7) >> 3))
1211			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1212	}
1213
1214	mcspi_write_chconf0(spi, chconf);
1215
1216	if (t->len) {
1217		unsigned	count;
1218
1219		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1220		    master->cur_msg_mapped &&
1221		    master->can_dma(master, spi, t))
1222			omap2_mcspi_set_fifo(spi, t, 1);
1223
1224		omap2_mcspi_set_enable(spi, 1);
 
 
 
 
 
1225
1226		/* RX_ONLY mode needs dummy data in TX reg */
1227		if (t->tx_buf == NULL)
1228			writel_relaxed(0, cs->base
1229					+ OMAP2_MCSPI_TX0);
1230
1231		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1232		    master->cur_msg_mapped &&
1233		    master->can_dma(master, spi, t))
1234			count = omap2_mcspi_txrx_dma(spi, t);
1235		else
1236			count = omap2_mcspi_txrx_pio(spi, t);
1237
1238		if (count != t->len) {
1239			status = -EIO;
1240			goto out;
1241		}
1242	}
1243
1244	omap2_mcspi_set_enable(spi, 0);
 
1245
1246	if (mcspi->fifo_depth > 0)
1247		omap2_mcspi_set_fifo(spi, t, 0);
1248
1249out:
1250	/* Restore defaults if they were overriden */
1251	if (par_override) {
1252		par_override = 0;
1253		status = omap2_mcspi_setup_transfer(spi, NULL);
1254	}
1255
1256	if (cd && cd->cs_per_word) {
1257		chconf = mcspi->ctx.modulctrl;
1258		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1259		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1260		mcspi->ctx.modulctrl =
1261			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1262	}
1263
1264	omap2_mcspi_set_enable(spi, 0);
1265
1266	if (gpio_is_valid(spi->cs_gpio))
1267		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1268
1269	if (mcspi->fifo_depth > 0 && t)
1270		omap2_mcspi_set_fifo(spi, t, 0);
 
 
 
1271
1272	return status;
1273}
1274
1275static int omap2_mcspi_prepare_message(struct spi_master *master,
1276				       struct spi_message *msg)
1277{
1278	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1279	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1280	struct omap2_mcspi_cs	*cs;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1281
1282	/* Only a single channel can have the FORCE bit enabled
1283	 * in its chconf0 register.
1284	 * Scan all channels and disable them except the current one.
1285	 * A FORCE can remain from a last transfer having cs_change enabled
1286	 */
1287	list_for_each_entry(cs, &ctx->cs, node) {
1288		if (msg->spi->controller_state == cs)
1289			continue;
1290
1291		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1292			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1293			writel_relaxed(cs->chconf0,
1294					cs->base + OMAP2_MCSPI_CHCONF0);
1295			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1296		}
1297	}
1298
1299	return 0;
1300}
1301
1302static bool omap2_mcspi_can_dma(struct spi_master *master,
1303				struct spi_device *spi,
1304				struct spi_transfer *xfer)
1305{
1306	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1307	struct omap2_mcspi_dma *mcspi_dma =
1308		&mcspi->dma_channels[spi->chip_select];
1309
1310	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1311		return false;
 
 
1312
1313	if (spi_controller_is_slave(master))
1314		return true;
1315
1316	return (xfer->len >= DMA_MIN_BYTES);
1317}
1318
1319static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1320{
1321	struct spi_master	*master = mcspi->master;
1322	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1323	int			ret = 0;
1324
1325	ret = pm_runtime_get_sync(mcspi->dev);
1326	if (ret < 0) {
1327		pm_runtime_put_noidle(mcspi->dev);
1328
1329		return ret;
1330	}
 
1331
1332	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1333			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1334	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1335
1336	omap2_mcspi_set_mode(master);
1337	pm_runtime_mark_last_busy(mcspi->dev);
1338	pm_runtime_put_autosuspend(mcspi->dev);
1339	return 0;
1340}
1341
1342/*
1343 * When SPI wake up from off-mode, CS is in activate state. If it was in
1344 * inactive state when driver was suspend, then force it to inactive state at
1345 * wake up.
1346 */
1347static int omap_mcspi_runtime_resume(struct device *dev)
1348{
1349	struct spi_master *master = dev_get_drvdata(dev);
1350	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1351	struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1352	struct omap2_mcspi_cs *cs;
1353
1354	/* McSPI: context restore */
1355	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1356	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1357
1358	list_for_each_entry(cs, &ctx->cs, node) {
1359		/*
1360		 * We need to toggle CS state for OMAP take this
1361		 * change in account.
1362		 */
1363		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1364			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1365			writel_relaxed(cs->chconf0,
1366				       cs->base + OMAP2_MCSPI_CHCONF0);
1367			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1368			writel_relaxed(cs->chconf0,
1369				       cs->base + OMAP2_MCSPI_CHCONF0);
1370		} else {
1371			writel_relaxed(cs->chconf0,
1372				       cs->base + OMAP2_MCSPI_CHCONF0);
1373		}
1374	}
1375
1376	return 0;
1377}
1378
1379static struct omap2_mcspi_platform_config omap2_pdata = {
1380	.regs_offset = 0,
1381};
1382
1383static struct omap2_mcspi_platform_config omap4_pdata = {
1384	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1385};
1386
1387static const struct of_device_id omap_mcspi_of_match[] = {
1388	{
1389		.compatible = "ti,omap2-mcspi",
1390		.data = &omap2_pdata,
1391	},
1392	{
1393		.compatible = "ti,omap4-mcspi",
1394		.data = &omap4_pdata,
1395	},
1396	{ },
1397};
1398MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1399
1400static int omap2_mcspi_probe(struct platform_device *pdev)
1401{
1402	struct spi_master	*master;
1403	const struct omap2_mcspi_platform_config *pdata;
1404	struct omap2_mcspi	*mcspi;
1405	struct resource		*r;
1406	int			status = 0, i;
1407	u32			regs_offset = 0;
1408	struct device_node	*node = pdev->dev.of_node;
1409	const struct of_device_id *match;
1410
1411	if (of_property_read_bool(node, "spi-slave"))
1412		master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1413	else
1414		master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1415	if (!master)
1416		return -ENOMEM;
 
1417
1418	/* the spi->mode bits understood by this driver: */
1419	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1420	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
 
 
 
1421	master->setup = omap2_mcspi_setup;
1422	master->auto_runtime_pm = true;
1423	master->prepare_message = omap2_mcspi_prepare_message;
1424	master->can_dma = omap2_mcspi_can_dma;
1425	master->transfer_one = omap2_mcspi_transfer_one;
1426	master->set_cs = omap2_mcspi_set_cs;
1427	master->cleanup = omap2_mcspi_cleanup;
1428	master->slave_abort = omap2_mcspi_slave_abort;
1429	master->dev.of_node = node;
1430	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1431	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1432
1433	platform_set_drvdata(pdev, master);
1434
1435	mcspi = spi_master_get_devdata(master);
1436	mcspi->master = master;
1437
1438	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1439	if (match) {
1440		u32 num_cs = 1; /* default number of chipselect */
1441		pdata = match->data;
1442
1443		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1444		master->num_chipselect = num_cs;
1445		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1446			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1447	} else {
1448		pdata = dev_get_platdata(&pdev->dev);
1449		master->num_chipselect = pdata->num_cs;
1450		mcspi->pin_dir = pdata->pin_dir;
1451	}
1452	regs_offset = pdata->regs_offset;
1453
1454	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1455	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1456	if (IS_ERR(mcspi->base)) {
1457		status = PTR_ERR(mcspi->base);
1458		goto free_master;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1459	}
1460	mcspi->phys = r->start + regs_offset;
1461	mcspi->base += regs_offset;
1462
1463	mcspi->dev = &pdev->dev;
 
1464
1465	INIT_LIST_HEAD(&mcspi->ctx.cs);
 
 
 
 
 
 
1466
1467	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1468					   sizeof(struct omap2_mcspi_dma),
1469					   GFP_KERNEL);
1470	if (mcspi->dma_channels == NULL) {
1471		status = -ENOMEM;
1472		goto free_master;
1473	}
1474
1475	for (i = 0; i < master->num_chipselect; i++) {
1476		sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1477		sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1478	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1479
1480	status = platform_get_irq(pdev, 0);
1481	if (status == -EPROBE_DEFER)
1482		goto free_master;
1483	if (status < 0) {
1484		dev_err(&pdev->dev, "no irq resource found\n");
1485		goto free_master;
1486	}
1487	init_completion(&mcspi->txdone);
1488	status = devm_request_irq(&pdev->dev, status,
1489				  omap2_mcspi_irq_handler, 0, pdev->name,
1490				  mcspi);
1491	if (status) {
1492		dev_err(&pdev->dev, "Cannot request IRQ");
1493		goto free_master;
1494	}
1495
1496	pm_runtime_use_autosuspend(&pdev->dev);
1497	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1498	pm_runtime_enable(&pdev->dev);
1499
1500	status = omap2_mcspi_controller_setup(mcspi);
1501	if (status < 0)
1502		goto disable_pm;
1503
1504	status = devm_spi_register_controller(&pdev->dev, master);
1505	if (status < 0)
1506		goto disable_pm;
1507
1508	return status;
1509
1510disable_pm:
1511	pm_runtime_dont_use_autosuspend(&pdev->dev);
1512	pm_runtime_put_sync(&pdev->dev);
1513	pm_runtime_disable(&pdev->dev);
1514free_master:
1515	spi_master_put(master);
 
 
 
 
 
 
1516	return status;
1517}
1518
1519static int omap2_mcspi_remove(struct platform_device *pdev)
1520{
1521	struct spi_master *master = platform_get_drvdata(pdev);
1522	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 
 
 
 
 
 
 
 
 
 
 
1523
1524	pm_runtime_dont_use_autosuspend(mcspi->dev);
1525	pm_runtime_put_sync(mcspi->dev);
1526	pm_runtime_disable(&pdev->dev);
 
1527
1528	return 0;
1529}
1530
1531/* work with hotplug and coldplug */
1532MODULE_ALIAS("platform:omap2_mcspi");
1533
1534static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
 
 
 
 
 
 
1535{
1536	struct spi_master *master = dev_get_drvdata(dev);
1537	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1538	int error;
1539
1540	error = pinctrl_pm_select_sleep_state(dev);
1541	if (error)
1542		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1543			 __func__, error);
1544
1545	error = spi_master_suspend(master);
1546	if (error)
1547		dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1548			 __func__, error);
1549
1550	return pm_runtime_force_suspend(dev);
1551}
1552
1553static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1554{
1555	struct spi_master *master = dev_get_drvdata(dev);
1556	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1557	int error;
1558
1559	error = pinctrl_pm_select_default_state(dev);
1560	if (error)
1561		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1562			 __func__, error);
1563
1564	error = spi_master_resume(master);
1565	if (error)
1566		dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1567			 __func__, error);
1568
1569	return pm_runtime_force_resume(dev);
1570}
 
 
 
1571
1572static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1573	SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1574				omap2_mcspi_resume)
1575	.runtime_resume	= omap_mcspi_runtime_resume,
1576};
1577
1578static struct platform_driver omap2_mcspi_driver = {
1579	.driver = {
1580		.name =		"omap2_mcspi",
1581		.pm =		&omap2_mcspi_pm_ops,
1582		.of_match_table = omap_mcspi_of_match,
1583	},
1584	.probe =	omap2_mcspi_probe,
1585	.remove =	omap2_mcspi_remove,
1586};
1587
1588module_platform_driver(omap2_mcspi_driver);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1589MODULE_LICENSE("GPL");