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v6.2
   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 Yrjola <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
  28#include <linux/spi/spi.h>
  29
  30#include <linux/platform_data/spi-omap2-mcspi.h>
  31
  32#define OMAP2_MCSPI_MAX_FREQ		48000000
  33#define OMAP2_MCSPI_MAX_DIVIDER		4096
  34#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  35#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  36#define SPI_AUTOSUSPEND_TIMEOUT		2000
  37
  38#define OMAP2_MCSPI_REVISION		0x00
  39#define OMAP2_MCSPI_SYSSTATUS		0x14
  40#define OMAP2_MCSPI_IRQSTATUS		0x18
  41#define OMAP2_MCSPI_IRQENABLE		0x1c
  42#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  43#define OMAP2_MCSPI_SYST		0x24
  44#define OMAP2_MCSPI_MODULCTRL		0x28
  45#define OMAP2_MCSPI_XFERLEVEL		0x7c
  46
  47/* per-channel banks, 0x14 bytes each, first is: */
  48#define OMAP2_MCSPI_CHCONF0		0x2c
  49#define OMAP2_MCSPI_CHSTAT0		0x30
  50#define OMAP2_MCSPI_CHCTRL0		0x34
  51#define OMAP2_MCSPI_TX0			0x38
  52#define OMAP2_MCSPI_RX0			0x3c
  53
  54/* per-register bitmasks: */
  55#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  56
  57#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  58#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  59#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  60
  61#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  62#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  63#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  64#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  65#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  66#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  67#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  68#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  69#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  70#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  71#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  72#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  73#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  74#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  75#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  76#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  77#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  78#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  79
  80#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  81#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  82#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  83#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  84
  85#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
  86#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
  87
  88#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  89
  90/* We have 2 DMA channels per CS, one for RX and one for TX */
  91struct omap2_mcspi_dma {
  92	struct dma_chan *dma_tx;
  93	struct dma_chan *dma_rx;
  94
  95	struct completion dma_tx_completion;
  96	struct completion dma_rx_completion;
  97
  98	char dma_rx_ch_name[14];
  99	char dma_tx_ch_name[14];
 100};
 101
 102/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 103 * cache operations; better heuristics consider wordsize and bitrate.
 104 */
 105#define DMA_MIN_BYTES			160
 106
 107
 108/*
 109 * Used for context save and restore, structure members to be updated whenever
 110 * corresponding registers are modified.
 111 */
 112struct omap2_mcspi_regs {
 113	u32 modulctrl;
 114	u32 wakeupenable;
 115	struct list_head cs;
 116};
 117
 118struct omap2_mcspi {
 119	struct completion	txdone;
 120	struct spi_master	*master;
 121	/* Virtual base address of the controller */
 122	void __iomem		*base;
 123	unsigned long		phys;
 124	/* SPI1 has 4 channels, while SPI2 has 2 */
 125	struct omap2_mcspi_dma	*dma_channels;
 126	struct device		*dev;
 127	struct omap2_mcspi_regs ctx;
 128	int			fifo_depth;
 129	bool			slave_aborted;
 130	unsigned int		pin_dir:1;
 131	size_t			max_xfer_len;
 132};
 133
 134struct omap2_mcspi_cs {
 135	void __iomem		*base;
 136	unsigned long		phys;
 137	int			word_len;
 138	u16			mode;
 139	struct list_head	node;
 140	/* Context save and restore shadow register */
 141	u32			chconf0, chctrl0;
 142};
 143
 144static inline void mcspi_write_reg(struct spi_master *master,
 145		int idx, u32 val)
 146{
 147	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 148
 149	writel_relaxed(val, mcspi->base + idx);
 150}
 151
 152static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 153{
 154	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 155
 156	return readl_relaxed(mcspi->base + idx);
 157}
 158
 159static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 160		int idx, u32 val)
 161{
 162	struct omap2_mcspi_cs	*cs = spi->controller_state;
 163
 164	writel_relaxed(val, cs->base +  idx);
 165}
 166
 167static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 168{
 169	struct omap2_mcspi_cs	*cs = spi->controller_state;
 170
 171	return readl_relaxed(cs->base + idx);
 172}
 173
 174static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 175{
 176	struct omap2_mcspi_cs *cs = spi->controller_state;
 177
 178	return cs->chconf0;
 179}
 180
 181static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 182{
 183	struct omap2_mcspi_cs *cs = spi->controller_state;
 184
 185	cs->chconf0 = val;
 186	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 187	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 188}
 189
 190static inline int mcspi_bytes_per_word(int word_len)
 191{
 192	if (word_len <= 8)
 193		return 1;
 194	else if (word_len <= 16)
 195		return 2;
 196	else /* word_len <= 32 */
 197		return 4;
 198}
 199
 200static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 201		int is_read, int enable)
 202{
 203	u32 l, rw;
 204
 205	l = mcspi_cached_chconf0(spi);
 206
 207	if (is_read) /* 1 is read, 0 write */
 208		rw = OMAP2_MCSPI_CHCONF_DMAR;
 209	else
 210		rw = OMAP2_MCSPI_CHCONF_DMAW;
 211
 212	if (enable)
 213		l |= rw;
 214	else
 215		l &= ~rw;
 216
 217	mcspi_write_chconf0(spi, l);
 218}
 219
 220static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 221{
 222	struct omap2_mcspi_cs *cs = spi->controller_state;
 223	u32 l;
 224
 225	l = cs->chctrl0;
 226	if (enable)
 227		l |= OMAP2_MCSPI_CHCTRL_EN;
 228	else
 229		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 230	cs->chctrl0 = l;
 231	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 232	/* Flash post-writes */
 233	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 234}
 235
 236static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 237{
 238	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 239	u32 l;
 240
 241	/* The controller handles the inverted chip selects
 242	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 243	 * the inversion from the core spi_set_cs function.
 244	 */
 245	if (spi->mode & SPI_CS_HIGH)
 246		enable = !enable;
 247
 248	if (spi->controller_state) {
 249		int err = pm_runtime_resume_and_get(mcspi->dev);
 250		if (err < 0) {
 
 251			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 252			return;
 253		}
 254
 255		l = mcspi_cached_chconf0(spi);
 256
 257		if (enable)
 258			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 259		else
 260			l |= OMAP2_MCSPI_CHCONF_FORCE;
 261
 262		mcspi_write_chconf0(spi, l);
 263
 264		pm_runtime_mark_last_busy(mcspi->dev);
 265		pm_runtime_put_autosuspend(mcspi->dev);
 266	}
 267}
 268
 269static void omap2_mcspi_set_mode(struct spi_master *master)
 270{
 271	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 272	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 273	u32 l;
 274
 275	/*
 276	 * Choose master or slave mode
 277	 */
 278	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 279	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
 280	if (spi_controller_is_slave(master)) {
 281		l |= (OMAP2_MCSPI_MODULCTRL_MS);
 282	} else {
 283		l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
 284		l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 285	}
 286	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 287
 288	ctx->modulctrl = l;
 289}
 290
 291static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 292				struct spi_transfer *t, int enable)
 293{
 294	struct spi_master *master = spi->master;
 295	struct omap2_mcspi_cs *cs = spi->controller_state;
 296	struct omap2_mcspi *mcspi;
 297	unsigned int wcnt;
 298	int max_fifo_depth, bytes_per_word;
 299	u32 chconf, xferlevel;
 300
 301	mcspi = spi_master_get_devdata(master);
 302
 303	chconf = mcspi_cached_chconf0(spi);
 304	if (enable) {
 305		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 306		if (t->len % bytes_per_word != 0)
 307			goto disable_fifo;
 308
 309		if (t->rx_buf != NULL && t->tx_buf != NULL)
 310			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 311		else
 312			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 313
 314		wcnt = t->len / bytes_per_word;
 315		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 316			goto disable_fifo;
 317
 318		xferlevel = wcnt << 16;
 319		if (t->rx_buf != NULL) {
 320			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 321			xferlevel |= (bytes_per_word - 1) << 8;
 322		}
 323
 324		if (t->tx_buf != NULL) {
 325			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 326			xferlevel |= bytes_per_word - 1;
 327		}
 328
 329		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 330		mcspi_write_chconf0(spi, chconf);
 331		mcspi->fifo_depth = max_fifo_depth;
 332
 333		return;
 334	}
 335
 336disable_fifo:
 337	if (t->rx_buf != NULL)
 338		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 339
 340	if (t->tx_buf != NULL)
 341		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 342
 343	mcspi_write_chconf0(spi, chconf);
 344	mcspi->fifo_depth = 0;
 345}
 346
 347static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 348{
 349	unsigned long timeout;
 350
 351	timeout = jiffies + msecs_to_jiffies(1000);
 352	while (!(readl_relaxed(reg) & bit)) {
 353		if (time_after(jiffies, timeout)) {
 354			if (!(readl_relaxed(reg) & bit))
 355				return -ETIMEDOUT;
 356			else
 357				return 0;
 358		}
 359		cpu_relax();
 360	}
 361	return 0;
 362}
 363
 364static int mcspi_wait_for_completion(struct  omap2_mcspi *mcspi,
 365				     struct completion *x)
 366{
 367	if (spi_controller_is_slave(mcspi->master)) {
 368		if (wait_for_completion_interruptible(x) ||
 369		    mcspi->slave_aborted)
 370			return -EINTR;
 371	} else {
 372		wait_for_completion(x);
 373	}
 374
 375	return 0;
 376}
 377
 378static void omap2_mcspi_rx_callback(void *data)
 379{
 380	struct spi_device *spi = data;
 381	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 382	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 383
 384	/* We must disable the DMA RX request */
 385	omap2_mcspi_set_dma_req(spi, 1, 0);
 386
 387	complete(&mcspi_dma->dma_rx_completion);
 388}
 389
 390static void omap2_mcspi_tx_callback(void *data)
 391{
 392	struct spi_device *spi = data;
 393	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 394	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 395
 396	/* We must disable the DMA TX request */
 397	omap2_mcspi_set_dma_req(spi, 0, 0);
 398
 399	complete(&mcspi_dma->dma_tx_completion);
 400}
 401
 402static void omap2_mcspi_tx_dma(struct spi_device *spi,
 403				struct spi_transfer *xfer,
 404				struct dma_slave_config cfg)
 405{
 406	struct omap2_mcspi	*mcspi;
 407	struct omap2_mcspi_dma  *mcspi_dma;
 408	struct dma_async_tx_descriptor *tx;
 409
 410	mcspi = spi_master_get_devdata(spi->master);
 411	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 412
 413	dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 414
 415	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 416				     xfer->tx_sg.nents,
 417				     DMA_MEM_TO_DEV,
 418				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 419	if (tx) {
 420		tx->callback = omap2_mcspi_tx_callback;
 421		tx->callback_param = spi;
 422		dmaengine_submit(tx);
 423	} else {
 424		/* FIXME: fall back to PIO? */
 425	}
 426	dma_async_issue_pending(mcspi_dma->dma_tx);
 427	omap2_mcspi_set_dma_req(spi, 0, 1);
 428}
 429
 430static unsigned
 431omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 432				struct dma_slave_config cfg,
 433				unsigned es)
 434{
 435	struct omap2_mcspi	*mcspi;
 436	struct omap2_mcspi_dma  *mcspi_dma;
 437	unsigned int		count, transfer_reduction = 0;
 438	struct scatterlist	*sg_out[2];
 439	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 440	size_t			sizes[2];
 441	u32			l;
 442	int			elements = 0;
 443	int			word_len, element_count;
 444	struct omap2_mcspi_cs	*cs = spi->controller_state;
 445	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 446	struct dma_async_tx_descriptor *tx;
 447
 448	mcspi = spi_master_get_devdata(spi->master);
 449	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 450	count = xfer->len;
 451
 452	/*
 453	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 454	 *  it mentions reducing DMA transfer length by one element in master
 455	 *  normal mode.
 456	 */
 457	if (mcspi->fifo_depth == 0)
 458		transfer_reduction = es;
 459
 460	word_len = cs->word_len;
 461	l = mcspi_cached_chconf0(spi);
 462
 463	if (word_len <= 8)
 464		element_count = count;
 465	else if (word_len <= 16)
 466		element_count = count >> 1;
 467	else /* word_len <= 32 */
 468		element_count = count >> 2;
 469
 470
 471	dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 472
 473	/*
 474	 *  Reduce DMA transfer length by one more if McSPI is
 475	 *  configured in turbo mode.
 476	 */
 477	if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 478		transfer_reduction += es;
 479
 480	if (transfer_reduction) {
 481		/* Split sgl into two. The second sgl won't be used. */
 482		sizes[0] = count - transfer_reduction;
 483		sizes[1] = transfer_reduction;
 484		nb_sizes = 2;
 485	} else {
 486		/*
 487		 * Don't bother splitting the sgl. This essentially
 488		 * clones the original sgl.
 489		 */
 490		sizes[0] = count;
 491		nb_sizes = 1;
 492	}
 493
 494	ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
 495		       sizes, sg_out, out_mapped_nents, 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, sg_out[0],
 503				     out_mapped_nents[0], DMA_DEV_TO_MEM,
 504				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 505	if (tx) {
 506		tx->callback = omap2_mcspi_rx_callback;
 507		tx->callback_param = spi;
 508		dmaengine_submit(tx);
 509	} else {
 510		/* FIXME: fall back to PIO? */
 511	}
 512
 513	dma_async_issue_pending(mcspi_dma->dma_rx);
 514	omap2_mcspi_set_dma_req(spi, 1, 1);
 515
 516	ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
 517	if (ret || mcspi->slave_aborted) {
 518		dmaengine_terminate_sync(mcspi_dma->dma_rx);
 519		omap2_mcspi_set_dma_req(spi, 1, 0);
 520		return 0;
 521	}
 522
 523	for (x = 0; x < nb_sizes; x++)
 524		kfree(sg_out[x]);
 525
 526	if (mcspi->fifo_depth > 0)
 527		return count;
 528
 529	/*
 530	 *  Due to the DMA transfer length reduction the missing bytes must
 531	 *  be read manually to receive all of the expected data.
 532	 */
 533	omap2_mcspi_set_enable(spi, 0);
 534
 535	elements = element_count - 1;
 536
 537	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 538		elements--;
 539
 540		if (!mcspi_wait_for_reg_bit(chstat_reg,
 541					    OMAP2_MCSPI_CHSTAT_RXS)) {
 542			u32 w;
 543
 544			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 545			if (word_len <= 8)
 546				((u8 *)xfer->rx_buf)[elements++] = w;
 547			else if (word_len <= 16)
 548				((u16 *)xfer->rx_buf)[elements++] = w;
 549			else /* word_len <= 32 */
 550				((u32 *)xfer->rx_buf)[elements++] = w;
 551		} else {
 552			int bytes_per_word = mcspi_bytes_per_word(word_len);
 553			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 554			count -= (bytes_per_word << 1);
 555			omap2_mcspi_set_enable(spi, 1);
 556			return count;
 557		}
 558	}
 559	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 560		u32 w;
 561
 562		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 563		if (word_len <= 8)
 564			((u8 *)xfer->rx_buf)[elements] = w;
 565		else if (word_len <= 16)
 566			((u16 *)xfer->rx_buf)[elements] = w;
 567		else /* word_len <= 32 */
 568			((u32 *)xfer->rx_buf)[elements] = w;
 569	} else {
 570		dev_err(&spi->dev, "DMA RX last word empty\n");
 571		count -= mcspi_bytes_per_word(word_len);
 572	}
 573	omap2_mcspi_set_enable(spi, 1);
 574	return count;
 575}
 576
 577static unsigned
 578omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 579{
 580	struct omap2_mcspi	*mcspi;
 581	struct omap2_mcspi_cs	*cs = spi->controller_state;
 582	struct omap2_mcspi_dma  *mcspi_dma;
 583	unsigned int		count;
 584	u8			*rx;
 585	const u8		*tx;
 586	struct dma_slave_config	cfg;
 587	enum dma_slave_buswidth width;
 588	unsigned es;
 589	void __iomem		*chstat_reg;
 590	void __iomem            *irqstat_reg;
 591	int			wait_res;
 592
 593	mcspi = spi_master_get_devdata(spi->master);
 594	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 595
 596	if (cs->word_len <= 8) {
 597		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 598		es = 1;
 599	} else if (cs->word_len <= 16) {
 600		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 601		es = 2;
 602	} else {
 603		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 604		es = 4;
 605	}
 606
 607	count = xfer->len;
 608
 609	memset(&cfg, 0, sizeof(cfg));
 610	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 611	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 612	cfg.src_addr_width = width;
 613	cfg.dst_addr_width = width;
 614	cfg.src_maxburst = 1;
 615	cfg.dst_maxburst = 1;
 616
 617	rx = xfer->rx_buf;
 618	tx = xfer->tx_buf;
 619
 620	mcspi->slave_aborted = false;
 621	reinit_completion(&mcspi_dma->dma_tx_completion);
 622	reinit_completion(&mcspi_dma->dma_rx_completion);
 623	reinit_completion(&mcspi->txdone);
 624	if (tx) {
 625		/* Enable EOW IRQ to know end of tx in slave mode */
 626		if (spi_controller_is_slave(spi->master))
 627			mcspi_write_reg(spi->master,
 628					OMAP2_MCSPI_IRQENABLE,
 629					OMAP2_MCSPI_IRQSTATUS_EOW);
 630		omap2_mcspi_tx_dma(spi, xfer, cfg);
 631	}
 632
 633	if (rx != NULL)
 634		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 635
 636	if (tx != NULL) {
 637		int ret;
 638
 639		ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
 640		if (ret || mcspi->slave_aborted) {
 641			dmaengine_terminate_sync(mcspi_dma->dma_tx);
 642			omap2_mcspi_set_dma_req(spi, 0, 0);
 643			return 0;
 644		}
 645
 646		if (spi_controller_is_slave(mcspi->master)) {
 647			ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
 648			if (ret || mcspi->slave_aborted)
 649				return 0;
 650		}
 651
 652		if (mcspi->fifo_depth > 0) {
 653			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 654
 655			if (mcspi_wait_for_reg_bit(irqstat_reg,
 656						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 657				dev_err(&spi->dev, "EOW timed out\n");
 658
 659			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 660					OMAP2_MCSPI_IRQSTATUS_EOW);
 661		}
 662
 663		/* for TX_ONLY mode, be sure all words have shifted out */
 664		if (rx == NULL) {
 665			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 666			if (mcspi->fifo_depth > 0) {
 667				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 668						OMAP2_MCSPI_CHSTAT_TXFFE);
 669				if (wait_res < 0)
 670					dev_err(&spi->dev, "TXFFE timed out\n");
 671			} else {
 672				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 673						OMAP2_MCSPI_CHSTAT_TXS);
 674				if (wait_res < 0)
 675					dev_err(&spi->dev, "TXS timed out\n");
 676			}
 677			if (wait_res >= 0 &&
 678				(mcspi_wait_for_reg_bit(chstat_reg,
 679					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 680				dev_err(&spi->dev, "EOT timed out\n");
 681		}
 682	}
 683	return count;
 684}
 685
 686static unsigned
 687omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 688{
 689	struct omap2_mcspi_cs	*cs = spi->controller_state;
 690	unsigned int		count, c;
 691	u32			l;
 692	void __iomem		*base = cs->base;
 693	void __iomem		*tx_reg;
 694	void __iomem		*rx_reg;
 695	void __iomem		*chstat_reg;
 696	int			word_len;
 697
 698	count = xfer->len;
 699	c = count;
 700	word_len = cs->word_len;
 701
 702	l = mcspi_cached_chconf0(spi);
 703
 704	/* We store the pre-calculated register addresses on stack to speed
 705	 * up the transfer loop. */
 706	tx_reg		= base + OMAP2_MCSPI_TX0;
 707	rx_reg		= base + OMAP2_MCSPI_RX0;
 708	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 709
 710	if (c < (word_len>>3))
 711		return 0;
 712
 713	if (word_len <= 8) {
 714		u8		*rx;
 715		const u8	*tx;
 716
 717		rx = xfer->rx_buf;
 718		tx = xfer->tx_buf;
 719
 720		do {
 721			c -= 1;
 722			if (tx != NULL) {
 723				if (mcspi_wait_for_reg_bit(chstat_reg,
 724						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 725					dev_err(&spi->dev, "TXS timed out\n");
 726					goto out;
 727				}
 728				dev_vdbg(&spi->dev, "write-%d %02x\n",
 729						word_len, *tx);
 730				writel_relaxed(*tx++, tx_reg);
 731			}
 732			if (rx != NULL) {
 733				if (mcspi_wait_for_reg_bit(chstat_reg,
 734						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 735					dev_err(&spi->dev, "RXS timed out\n");
 736					goto out;
 737				}
 738
 739				if (c == 1 && tx == NULL &&
 740				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 741					omap2_mcspi_set_enable(spi, 0);
 742					*rx++ = readl_relaxed(rx_reg);
 743					dev_vdbg(&spi->dev, "read-%d %02x\n",
 744						    word_len, *(rx - 1));
 745					if (mcspi_wait_for_reg_bit(chstat_reg,
 746						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 747						dev_err(&spi->dev,
 748							"RXS timed out\n");
 749						goto out;
 750					}
 751					c = 0;
 752				} else if (c == 0 && tx == NULL) {
 753					omap2_mcspi_set_enable(spi, 0);
 754				}
 755
 756				*rx++ = readl_relaxed(rx_reg);
 757				dev_vdbg(&spi->dev, "read-%d %02x\n",
 758						word_len, *(rx - 1));
 759			}
 760			/* Add word delay between each word */
 761			spi_delay_exec(&xfer->word_delay, xfer);
 762		} while (c);
 763	} else if (word_len <= 16) {
 764		u16		*rx;
 765		const u16	*tx;
 766
 767		rx = xfer->rx_buf;
 768		tx = xfer->tx_buf;
 769		do {
 770			c -= 2;
 771			if (tx != NULL) {
 772				if (mcspi_wait_for_reg_bit(chstat_reg,
 773						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 774					dev_err(&spi->dev, "TXS timed out\n");
 775					goto out;
 776				}
 777				dev_vdbg(&spi->dev, "write-%d %04x\n",
 778						word_len, *tx);
 779				writel_relaxed(*tx++, tx_reg);
 780			}
 781			if (rx != NULL) {
 782				if (mcspi_wait_for_reg_bit(chstat_reg,
 783						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 784					dev_err(&spi->dev, "RXS timed out\n");
 785					goto out;
 786				}
 787
 788				if (c == 2 && tx == NULL &&
 789				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 790					omap2_mcspi_set_enable(spi, 0);
 791					*rx++ = readl_relaxed(rx_reg);
 792					dev_vdbg(&spi->dev, "read-%d %04x\n",
 793						    word_len, *(rx - 1));
 794					if (mcspi_wait_for_reg_bit(chstat_reg,
 795						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 796						dev_err(&spi->dev,
 797							"RXS timed out\n");
 798						goto out;
 799					}
 800					c = 0;
 801				} else if (c == 0 && tx == NULL) {
 802					omap2_mcspi_set_enable(spi, 0);
 803				}
 804
 805				*rx++ = readl_relaxed(rx_reg);
 806				dev_vdbg(&spi->dev, "read-%d %04x\n",
 807						word_len, *(rx - 1));
 808			}
 809			/* Add word delay between each word */
 810			spi_delay_exec(&xfer->word_delay, xfer);
 811		} while (c >= 2);
 812	} else if (word_len <= 32) {
 813		u32		*rx;
 814		const u32	*tx;
 815
 816		rx = xfer->rx_buf;
 817		tx = xfer->tx_buf;
 818		do {
 819			c -= 4;
 820			if (tx != NULL) {
 821				if (mcspi_wait_for_reg_bit(chstat_reg,
 822						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 823					dev_err(&spi->dev, "TXS timed out\n");
 824					goto out;
 825				}
 826				dev_vdbg(&spi->dev, "write-%d %08x\n",
 827						word_len, *tx);
 828				writel_relaxed(*tx++, tx_reg);
 829			}
 830			if (rx != NULL) {
 831				if (mcspi_wait_for_reg_bit(chstat_reg,
 832						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 833					dev_err(&spi->dev, "RXS timed out\n");
 834					goto out;
 835				}
 836
 837				if (c == 4 && tx == NULL &&
 838				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 839					omap2_mcspi_set_enable(spi, 0);
 840					*rx++ = readl_relaxed(rx_reg);
 841					dev_vdbg(&spi->dev, "read-%d %08x\n",
 842						    word_len, *(rx - 1));
 843					if (mcspi_wait_for_reg_bit(chstat_reg,
 844						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 845						dev_err(&spi->dev,
 846							"RXS timed out\n");
 847						goto out;
 848					}
 849					c = 0;
 850				} else if (c == 0 && tx == NULL) {
 851					omap2_mcspi_set_enable(spi, 0);
 852				}
 853
 854				*rx++ = readl_relaxed(rx_reg);
 855				dev_vdbg(&spi->dev, "read-%d %08x\n",
 856						word_len, *(rx - 1));
 857			}
 858			/* Add word delay between each word */
 859			spi_delay_exec(&xfer->word_delay, xfer);
 860		} while (c >= 4);
 861	}
 862
 863	/* for TX_ONLY mode, be sure all words have shifted out */
 864	if (xfer->rx_buf == NULL) {
 865		if (mcspi_wait_for_reg_bit(chstat_reg,
 866				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 867			dev_err(&spi->dev, "TXS timed out\n");
 868		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 869				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 870			dev_err(&spi->dev, "EOT timed out\n");
 871
 872		/* disable chan to purge rx datas received in TX_ONLY transfer,
 873		 * otherwise these rx datas will affect the direct following
 874		 * RX_ONLY transfer.
 875		 */
 876		omap2_mcspi_set_enable(spi, 0);
 877	}
 878out:
 879	omap2_mcspi_set_enable(spi, 1);
 880	return count - c;
 881}
 882
 883static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 884{
 885	u32 div;
 886
 887	for (div = 0; div < 15; div++)
 888		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 889			return div;
 890
 891	return 15;
 892}
 893
 894/* called only when no transfer is active to this device */
 895static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 896		struct spi_transfer *t)
 897{
 898	struct omap2_mcspi_cs *cs = spi->controller_state;
 899	struct omap2_mcspi *mcspi;
 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
 906	if (t != NULL && t->bits_per_word)
 907		word_len = t->bits_per_word;
 908
 909	cs->word_len = word_len;
 910
 911	if (t && t->speed_hz)
 912		speed_hz = t->speed_hz;
 913
 914	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 915	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 916		clkd = omap2_mcspi_calc_divisor(speed_hz);
 917		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 918		clkg = 0;
 919	} else {
 920		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 921		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 922		clkd = (div - 1) & 0xf;
 923		extclk = (div - 1) >> 4;
 924		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 925	}
 926
 927	l = mcspi_cached_chconf0(spi);
 928
 929	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 930	 * REVISIT: this controller could support SPI_3WIRE mode.
 931	 */
 932	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 933		l &= ~OMAP2_MCSPI_CHCONF_IS;
 934		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 935		l |= OMAP2_MCSPI_CHCONF_DPE0;
 936	} else {
 937		l |= OMAP2_MCSPI_CHCONF_IS;
 938		l |= OMAP2_MCSPI_CHCONF_DPE1;
 939		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 940	}
 941
 942	/* wordlength */
 943	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 944	l |= (word_len - 1) << 7;
 945
 946	/* set chipselect polarity; manage with FORCE */
 947	if (!(spi->mode & SPI_CS_HIGH))
 948		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 949	else
 950		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 951
 952	/* set clock divisor */
 953	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 954	l |= clkd << 2;
 955
 956	/* set clock granularity */
 957	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 958	l |= clkg;
 959	if (clkg) {
 960		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 961		cs->chctrl0 |= extclk << 8;
 962		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 963	}
 964
 965	/* set SPI mode 0..3 */
 966	if (spi->mode & SPI_CPOL)
 967		l |= OMAP2_MCSPI_CHCONF_POL;
 968	else
 969		l &= ~OMAP2_MCSPI_CHCONF_POL;
 970	if (spi->mode & SPI_CPHA)
 971		l |= OMAP2_MCSPI_CHCONF_PHA;
 972	else
 973		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 974
 975	mcspi_write_chconf0(spi, l);
 976
 977	cs->mode = spi->mode;
 978
 979	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 980			speed_hz,
 981			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 982			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 983
 984	return 0;
 985}
 986
 987/*
 988 * Note that we currently allow DMA only if we get a channel
 989 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 990 */
 991static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
 992				   struct omap2_mcspi_dma *mcspi_dma)
 993{
 994	int ret = 0;
 995
 996	mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
 997					     mcspi_dma->dma_rx_ch_name);
 998	if (IS_ERR(mcspi_dma->dma_rx)) {
 999		ret = PTR_ERR(mcspi_dma->dma_rx);
1000		mcspi_dma->dma_rx = NULL;
1001		goto no_dma;
1002	}
1003
1004	mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
1005					     mcspi_dma->dma_tx_ch_name);
1006	if (IS_ERR(mcspi_dma->dma_tx)) {
1007		ret = PTR_ERR(mcspi_dma->dma_tx);
1008		mcspi_dma->dma_tx = NULL;
1009		dma_release_channel(mcspi_dma->dma_rx);
1010		mcspi_dma->dma_rx = NULL;
1011	}
1012
1013	init_completion(&mcspi_dma->dma_rx_completion);
1014	init_completion(&mcspi_dma->dma_tx_completion);
1015
1016no_dma:
1017	return ret;
1018}
1019
1020static void omap2_mcspi_release_dma(struct spi_master *master)
1021{
1022	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1023	struct omap2_mcspi_dma	*mcspi_dma;
1024	int i;
1025
1026	for (i = 0; i < master->num_chipselect; i++) {
1027		mcspi_dma = &mcspi->dma_channels[i];
1028
1029		if (mcspi_dma->dma_rx) {
1030			dma_release_channel(mcspi_dma->dma_rx);
1031			mcspi_dma->dma_rx = NULL;
1032		}
1033		if (mcspi_dma->dma_tx) {
1034			dma_release_channel(mcspi_dma->dma_tx);
1035			mcspi_dma->dma_tx = NULL;
1036		}
1037	}
1038}
1039
1040static void omap2_mcspi_cleanup(struct spi_device *spi)
1041{
1042	struct omap2_mcspi_cs	*cs;
1043
1044	if (spi->controller_state) {
1045		/* Unlink controller state from context save list */
1046		cs = spi->controller_state;
1047		list_del(&cs->node);
1048
1049		kfree(cs);
1050	}
1051}
1052
1053static int omap2_mcspi_setup(struct spi_device *spi)
1054{
1055	bool			initial_setup = false;
1056	int			ret;
1057	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
1058	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1059	struct omap2_mcspi_cs	*cs = spi->controller_state;
1060
1061	if (!cs) {
1062		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1063		if (!cs)
1064			return -ENOMEM;
1065		cs->base = mcspi->base + spi->chip_select * 0x14;
1066		cs->phys = mcspi->phys + spi->chip_select * 0x14;
1067		cs->mode = 0;
1068		cs->chconf0 = 0;
1069		cs->chctrl0 = 0;
1070		spi->controller_state = cs;
1071		/* Link this to context save list */
1072		list_add_tail(&cs->node, &ctx->cs);
1073		initial_setup = true;
1074	}
1075
1076	ret = pm_runtime_resume_and_get(mcspi->dev);
1077	if (ret < 0) {
 
1078		if (initial_setup)
1079			omap2_mcspi_cleanup(spi);
1080
1081		return ret;
1082	}
1083
1084	ret = omap2_mcspi_setup_transfer(spi, NULL);
1085	if (ret && initial_setup)
1086		omap2_mcspi_cleanup(spi);
1087
1088	pm_runtime_mark_last_busy(mcspi->dev);
1089	pm_runtime_put_autosuspend(mcspi->dev);
1090
1091	return ret;
1092}
1093
1094static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1095{
1096	struct omap2_mcspi *mcspi = data;
1097	u32 irqstat;
1098
1099	irqstat	= mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1100	if (!irqstat)
1101		return IRQ_NONE;
1102
1103	/* Disable IRQ and wakeup slave xfer task */
1104	mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1105	if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1106		complete(&mcspi->txdone);
1107
1108	return IRQ_HANDLED;
1109}
1110
1111static int omap2_mcspi_slave_abort(struct spi_master *master)
1112{
1113	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1114	struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1115
1116	mcspi->slave_aborted = true;
1117	complete(&mcspi_dma->dma_rx_completion);
1118	complete(&mcspi_dma->dma_tx_completion);
1119	complete(&mcspi->txdone);
1120
1121	return 0;
1122}
1123
1124static int omap2_mcspi_transfer_one(struct spi_master *master,
1125				    struct spi_device *spi,
1126				    struct spi_transfer *t)
1127{
1128
1129	/* We only enable one channel at a time -- the one whose message is
1130	 * -- although this controller would gladly
1131	 * arbitrate among multiple channels.  This corresponds to "single
1132	 * channel" master mode.  As a side effect, we need to manage the
1133	 * chipselect with the FORCE bit ... CS != channel enable.
1134	 */
1135
1136	struct omap2_mcspi		*mcspi;
1137	struct omap2_mcspi_dma		*mcspi_dma;
1138	struct omap2_mcspi_cs		*cs;
1139	struct omap2_mcspi_device_config *cd;
1140	int				par_override = 0;
1141	int				status = 0;
1142	u32				chconf;
1143
1144	mcspi = spi_master_get_devdata(master);
1145	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1146	cs = spi->controller_state;
1147	cd = spi->controller_data;
1148
1149	/*
1150	 * The slave driver could have changed spi->mode in which case
1151	 * it will be different from cs->mode (the current hardware setup).
1152	 * If so, set par_override (even though its not a parity issue) so
1153	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1154	 * with the correct mode on the first iteration of the loop below.
1155	 */
1156	if (spi->mode != cs->mode)
1157		par_override = 1;
1158
1159	omap2_mcspi_set_enable(spi, 0);
1160
1161	if (spi->cs_gpiod)
1162		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1163
1164	if (par_override ||
1165	    (t->speed_hz != spi->max_speed_hz) ||
1166	    (t->bits_per_word != spi->bits_per_word)) {
1167		par_override = 1;
1168		status = omap2_mcspi_setup_transfer(spi, t);
1169		if (status < 0)
1170			goto out;
1171		if (t->speed_hz == spi->max_speed_hz &&
1172		    t->bits_per_word == spi->bits_per_word)
1173			par_override = 0;
1174	}
1175	if (cd && cd->cs_per_word) {
1176		chconf = mcspi->ctx.modulctrl;
1177		chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1178		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1179		mcspi->ctx.modulctrl =
1180			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1181	}
1182
1183	chconf = mcspi_cached_chconf0(spi);
1184	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1185	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1186
1187	if (t->tx_buf == NULL)
1188		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1189	else if (t->rx_buf == NULL)
1190		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1191
1192	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1193		/* Turbo mode is for more than one word */
1194		if (t->len > ((cs->word_len + 7) >> 3))
1195			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1196	}
1197
1198	mcspi_write_chconf0(spi, chconf);
1199
1200	if (t->len) {
1201		unsigned	count;
1202
1203		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1204		    master->cur_msg_mapped &&
1205		    master->can_dma(master, spi, t))
1206			omap2_mcspi_set_fifo(spi, t, 1);
1207
1208		omap2_mcspi_set_enable(spi, 1);
1209
1210		/* RX_ONLY mode needs dummy data in TX reg */
1211		if (t->tx_buf == NULL)
1212			writel_relaxed(0, cs->base
1213					+ OMAP2_MCSPI_TX0);
1214
1215		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1216		    master->cur_msg_mapped &&
1217		    master->can_dma(master, spi, t))
1218			count = omap2_mcspi_txrx_dma(spi, t);
1219		else
1220			count = omap2_mcspi_txrx_pio(spi, t);
1221
1222		if (count != t->len) {
1223			status = -EIO;
1224			goto out;
1225		}
1226	}
1227
1228	omap2_mcspi_set_enable(spi, 0);
1229
1230	if (mcspi->fifo_depth > 0)
1231		omap2_mcspi_set_fifo(spi, t, 0);
1232
1233out:
1234	/* Restore defaults if they were overriden */
1235	if (par_override) {
1236		par_override = 0;
1237		status = omap2_mcspi_setup_transfer(spi, NULL);
1238	}
1239
1240	if (cd && cd->cs_per_word) {
1241		chconf = mcspi->ctx.modulctrl;
1242		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1243		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1244		mcspi->ctx.modulctrl =
1245			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1246	}
1247
1248	omap2_mcspi_set_enable(spi, 0);
1249
1250	if (spi->cs_gpiod)
1251		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1252
1253	if (mcspi->fifo_depth > 0 && t)
1254		omap2_mcspi_set_fifo(spi, t, 0);
1255
1256	return status;
1257}
1258
1259static int omap2_mcspi_prepare_message(struct spi_master *master,
1260				       struct spi_message *msg)
1261{
1262	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1263	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1264	struct omap2_mcspi_cs	*cs;
1265
1266	/* Only a single channel can have the FORCE bit enabled
1267	 * in its chconf0 register.
1268	 * Scan all channels and disable them except the current one.
1269	 * A FORCE can remain from a last transfer having cs_change enabled
1270	 */
1271	list_for_each_entry(cs, &ctx->cs, node) {
1272		if (msg->spi->controller_state == cs)
1273			continue;
1274
1275		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1276			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1277			writel_relaxed(cs->chconf0,
1278					cs->base + OMAP2_MCSPI_CHCONF0);
1279			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1280		}
1281	}
1282
1283	return 0;
1284}
1285
1286static bool omap2_mcspi_can_dma(struct spi_master *master,
1287				struct spi_device *spi,
1288				struct spi_transfer *xfer)
1289{
1290	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1291	struct omap2_mcspi_dma *mcspi_dma =
1292		&mcspi->dma_channels[spi->chip_select];
1293
1294	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1295		return false;
1296
1297	if (spi_controller_is_slave(master))
1298		return true;
1299
1300	master->dma_rx = mcspi_dma->dma_rx;
1301	master->dma_tx = mcspi_dma->dma_tx;
1302
1303	return (xfer->len >= DMA_MIN_BYTES);
1304}
1305
1306static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1307{
1308	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1309	struct omap2_mcspi_dma *mcspi_dma =
1310		&mcspi->dma_channels[spi->chip_select];
1311
1312	if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1313		return mcspi->max_xfer_len;
1314
1315	return SIZE_MAX;
1316}
1317
1318static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1319{
1320	struct spi_master	*master = mcspi->master;
1321	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1322	int			ret = 0;
1323
1324	ret = pm_runtime_resume_and_get(mcspi->dev);
1325	if (ret < 0)
 
 
1326		return ret;
 
1327
1328	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1329			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1330	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1331
1332	omap2_mcspi_set_mode(master);
1333	pm_runtime_mark_last_busy(mcspi->dev);
1334	pm_runtime_put_autosuspend(mcspi->dev);
1335	return 0;
1336}
1337
1338static int omap_mcspi_runtime_suspend(struct device *dev)
1339{
1340	int error;
1341
1342	error = pinctrl_pm_select_idle_state(dev);
1343	if (error)
1344		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1345
1346	return 0;
1347}
1348
1349/*
1350 * When SPI wake up from off-mode, CS is in activate state. If it was in
1351 * inactive state when driver was suspend, then force it to inactive state at
1352 * wake up.
1353 */
1354static int omap_mcspi_runtime_resume(struct device *dev)
1355{
1356	struct spi_master *master = dev_get_drvdata(dev);
1357	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1358	struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1359	struct omap2_mcspi_cs *cs;
1360	int error;
1361
1362	error = pinctrl_pm_select_default_state(dev);
1363	if (error)
1364		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1365
1366	/* McSPI: context restore */
1367	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1368	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1369
1370	list_for_each_entry(cs, &ctx->cs, node) {
1371		/*
1372		 * We need to toggle CS state for OMAP take this
1373		 * change in account.
1374		 */
1375		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1376			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1377			writel_relaxed(cs->chconf0,
1378				       cs->base + OMAP2_MCSPI_CHCONF0);
1379			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1380			writel_relaxed(cs->chconf0,
1381				       cs->base + OMAP2_MCSPI_CHCONF0);
1382		} else {
1383			writel_relaxed(cs->chconf0,
1384				       cs->base + OMAP2_MCSPI_CHCONF0);
1385		}
1386	}
1387
1388	return 0;
1389}
1390
1391static struct omap2_mcspi_platform_config omap2_pdata = {
1392	.regs_offset = 0,
1393};
1394
1395static struct omap2_mcspi_platform_config omap4_pdata = {
1396	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1397};
1398
1399static struct omap2_mcspi_platform_config am654_pdata = {
1400	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1401	.max_xfer_len = SZ_4K - 1,
1402};
1403
1404static const struct of_device_id omap_mcspi_of_match[] = {
1405	{
1406		.compatible = "ti,omap2-mcspi",
1407		.data = &omap2_pdata,
1408	},
1409	{
1410		.compatible = "ti,omap4-mcspi",
1411		.data = &omap4_pdata,
1412	},
1413	{
1414		.compatible = "ti,am654-mcspi",
1415		.data = &am654_pdata,
1416	},
1417	{ },
1418};
1419MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1420
1421static int omap2_mcspi_probe(struct platform_device *pdev)
1422{
1423	struct spi_master	*master;
1424	const struct omap2_mcspi_platform_config *pdata;
1425	struct omap2_mcspi	*mcspi;
1426	struct resource		*r;
1427	int			status = 0, i;
1428	u32			regs_offset = 0;
1429	struct device_node	*node = pdev->dev.of_node;
1430	const struct of_device_id *match;
1431
1432	if (of_property_read_bool(node, "spi-slave"))
1433		master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1434	else
1435		master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1436	if (!master)
1437		return -ENOMEM;
1438
1439	/* the spi->mode bits understood by this driver: */
1440	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1441	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1442	master->setup = omap2_mcspi_setup;
1443	master->auto_runtime_pm = true;
1444	master->prepare_message = omap2_mcspi_prepare_message;
1445	master->can_dma = omap2_mcspi_can_dma;
1446	master->transfer_one = omap2_mcspi_transfer_one;
1447	master->set_cs = omap2_mcspi_set_cs;
1448	master->cleanup = omap2_mcspi_cleanup;
1449	master->slave_abort = omap2_mcspi_slave_abort;
1450	master->dev.of_node = node;
1451	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1452	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1453	master->use_gpio_descriptors = true;
1454
1455	platform_set_drvdata(pdev, master);
1456
1457	mcspi = spi_master_get_devdata(master);
1458	mcspi->master = master;
1459
1460	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1461	if (match) {
1462		u32 num_cs = 1; /* default number of chipselect */
1463		pdata = match->data;
1464
1465		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1466		master->num_chipselect = num_cs;
1467		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1468			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1469	} else {
1470		pdata = dev_get_platdata(&pdev->dev);
1471		master->num_chipselect = pdata->num_cs;
1472		mcspi->pin_dir = pdata->pin_dir;
1473	}
1474	regs_offset = pdata->regs_offset;
1475	if (pdata->max_xfer_len) {
1476		mcspi->max_xfer_len = pdata->max_xfer_len;
1477		master->max_transfer_size = omap2_mcspi_max_xfer_size;
1478	}
1479
1480	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1481	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1482	if (IS_ERR(mcspi->base)) {
1483		status = PTR_ERR(mcspi->base);
1484		goto free_master;
1485	}
1486	mcspi->phys = r->start + regs_offset;
1487	mcspi->base += regs_offset;
1488
1489	mcspi->dev = &pdev->dev;
1490
1491	INIT_LIST_HEAD(&mcspi->ctx.cs);
1492
1493	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1494					   sizeof(struct omap2_mcspi_dma),
1495					   GFP_KERNEL);
1496	if (mcspi->dma_channels == NULL) {
1497		status = -ENOMEM;
1498		goto free_master;
1499	}
1500
1501	for (i = 0; i < master->num_chipselect; i++) {
1502		sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1503		sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1504
1505		status = omap2_mcspi_request_dma(mcspi,
1506						 &mcspi->dma_channels[i]);
1507		if (status == -EPROBE_DEFER)
1508			goto free_master;
1509	}
1510
1511	status = platform_get_irq(pdev, 0);
 
 
1512	if (status < 0) {
1513		dev_err_probe(&pdev->dev, status, "no irq resource found\n");
1514		goto free_master;
1515	}
1516	init_completion(&mcspi->txdone);
1517	status = devm_request_irq(&pdev->dev, status,
1518				  omap2_mcspi_irq_handler, 0, pdev->name,
1519				  mcspi);
1520	if (status) {
1521		dev_err(&pdev->dev, "Cannot request IRQ");
1522		goto free_master;
1523	}
1524
1525	pm_runtime_use_autosuspend(&pdev->dev);
1526	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1527	pm_runtime_enable(&pdev->dev);
1528
1529	status = omap2_mcspi_controller_setup(mcspi);
1530	if (status < 0)
1531		goto disable_pm;
1532
1533	status = devm_spi_register_controller(&pdev->dev, master);
1534	if (status < 0)
1535		goto disable_pm;
1536
1537	return status;
1538
1539disable_pm:
1540	pm_runtime_dont_use_autosuspend(&pdev->dev);
1541	pm_runtime_put_sync(&pdev->dev);
1542	pm_runtime_disable(&pdev->dev);
1543free_master:
1544	omap2_mcspi_release_dma(master);
1545	spi_master_put(master);
1546	return status;
1547}
1548
1549static int omap2_mcspi_remove(struct platform_device *pdev)
1550{
1551	struct spi_master *master = platform_get_drvdata(pdev);
1552	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1553
1554	omap2_mcspi_release_dma(master);
1555
1556	pm_runtime_dont_use_autosuspend(mcspi->dev);
1557	pm_runtime_put_sync(mcspi->dev);
1558	pm_runtime_disable(&pdev->dev);
1559
1560	return 0;
1561}
1562
1563/* work with hotplug and coldplug */
1564MODULE_ALIAS("platform:omap2_mcspi");
1565
1566static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1567{
1568	struct spi_master *master = dev_get_drvdata(dev);
1569	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1570	int error;
1571
1572	error = pinctrl_pm_select_sleep_state(dev);
1573	if (error)
1574		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1575			 __func__, error);
1576
1577	error = spi_master_suspend(master);
1578	if (error)
1579		dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1580			 __func__, error);
1581
1582	return pm_runtime_force_suspend(dev);
1583}
1584
1585static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1586{
1587	struct spi_master *master = dev_get_drvdata(dev);
1588	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1589	int error;
1590
1591	error = spi_master_resume(master);
1592	if (error)
1593		dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1594			 __func__, error);
1595
1596	return pm_runtime_force_resume(dev);
1597}
1598
1599static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1600	SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1601				omap2_mcspi_resume)
1602	.runtime_suspend	= omap_mcspi_runtime_suspend,
1603	.runtime_resume		= omap_mcspi_runtime_resume,
1604};
1605
1606static struct platform_driver omap2_mcspi_driver = {
1607	.driver = {
1608		.name =		"omap2_mcspi",
1609		.pm =		&omap2_mcspi_pm_ops,
1610		.of_match_table = omap_mcspi_of_match,
1611	},
1612	.probe =	omap2_mcspi_probe,
1613	.remove =	omap2_mcspi_remove,
1614};
1615
1616module_platform_driver(omap2_mcspi_driver);
1617MODULE_LICENSE("GPL");
v5.14.15
   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 Yrjola <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
  28#include <linux/spi/spi.h>
  29
  30#include <linux/platform_data/spi-omap2-mcspi.h>
  31
  32#define OMAP2_MCSPI_MAX_FREQ		48000000
  33#define OMAP2_MCSPI_MAX_DIVIDER		4096
  34#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  35#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  36#define SPI_AUTOSUSPEND_TIMEOUT		2000
  37
  38#define OMAP2_MCSPI_REVISION		0x00
  39#define OMAP2_MCSPI_SYSSTATUS		0x14
  40#define OMAP2_MCSPI_IRQSTATUS		0x18
  41#define OMAP2_MCSPI_IRQENABLE		0x1c
  42#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  43#define OMAP2_MCSPI_SYST		0x24
  44#define OMAP2_MCSPI_MODULCTRL		0x28
  45#define OMAP2_MCSPI_XFERLEVEL		0x7c
  46
  47/* per-channel banks, 0x14 bytes each, first is: */
  48#define OMAP2_MCSPI_CHCONF0		0x2c
  49#define OMAP2_MCSPI_CHSTAT0		0x30
  50#define OMAP2_MCSPI_CHCTRL0		0x34
  51#define OMAP2_MCSPI_TX0			0x38
  52#define OMAP2_MCSPI_RX0			0x3c
  53
  54/* per-register bitmasks: */
  55#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  56
  57#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  58#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  59#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  60
  61#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  62#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  63#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  64#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  65#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  66#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  67#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  68#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  69#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  70#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  71#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  72#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  73#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  74#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  75#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  76#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  77#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  78#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  79
  80#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  81#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  82#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  83#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  84
  85#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
  86#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
  87
  88#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  89
  90/* We have 2 DMA channels per CS, one for RX and one for TX */
  91struct omap2_mcspi_dma {
  92	struct dma_chan *dma_tx;
  93	struct dma_chan *dma_rx;
  94
  95	struct completion dma_tx_completion;
  96	struct completion dma_rx_completion;
  97
  98	char dma_rx_ch_name[14];
  99	char dma_tx_ch_name[14];
 100};
 101
 102/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 103 * cache operations; better heuristics consider wordsize and bitrate.
 104 */
 105#define DMA_MIN_BYTES			160
 106
 107
 108/*
 109 * Used for context save and restore, structure members to be updated whenever
 110 * corresponding registers are modified.
 111 */
 112struct omap2_mcspi_regs {
 113	u32 modulctrl;
 114	u32 wakeupenable;
 115	struct list_head cs;
 116};
 117
 118struct omap2_mcspi {
 119	struct completion	txdone;
 120	struct spi_master	*master;
 121	/* Virtual base address of the controller */
 122	void __iomem		*base;
 123	unsigned long		phys;
 124	/* SPI1 has 4 channels, while SPI2 has 2 */
 125	struct omap2_mcspi_dma	*dma_channels;
 126	struct device		*dev;
 127	struct omap2_mcspi_regs ctx;
 128	int			fifo_depth;
 129	bool			slave_aborted;
 130	unsigned int		pin_dir:1;
 131	size_t			max_xfer_len;
 132};
 133
 134struct omap2_mcspi_cs {
 135	void __iomem		*base;
 136	unsigned long		phys;
 137	int			word_len;
 138	u16			mode;
 139	struct list_head	node;
 140	/* Context save and restore shadow register */
 141	u32			chconf0, chctrl0;
 142};
 143
 144static inline void mcspi_write_reg(struct spi_master *master,
 145		int idx, u32 val)
 146{
 147	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 148
 149	writel_relaxed(val, mcspi->base + idx);
 150}
 151
 152static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 153{
 154	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 155
 156	return readl_relaxed(mcspi->base + idx);
 157}
 158
 159static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 160		int idx, u32 val)
 161{
 162	struct omap2_mcspi_cs	*cs = spi->controller_state;
 163
 164	writel_relaxed(val, cs->base +  idx);
 165}
 166
 167static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 168{
 169	struct omap2_mcspi_cs	*cs = spi->controller_state;
 170
 171	return readl_relaxed(cs->base + idx);
 172}
 173
 174static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 175{
 176	struct omap2_mcspi_cs *cs = spi->controller_state;
 177
 178	return cs->chconf0;
 179}
 180
 181static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 182{
 183	struct omap2_mcspi_cs *cs = spi->controller_state;
 184
 185	cs->chconf0 = val;
 186	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 187	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 188}
 189
 190static inline int mcspi_bytes_per_word(int word_len)
 191{
 192	if (word_len <= 8)
 193		return 1;
 194	else if (word_len <= 16)
 195		return 2;
 196	else /* word_len <= 32 */
 197		return 4;
 198}
 199
 200static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 201		int is_read, int enable)
 202{
 203	u32 l, rw;
 204
 205	l = mcspi_cached_chconf0(spi);
 206
 207	if (is_read) /* 1 is read, 0 write */
 208		rw = OMAP2_MCSPI_CHCONF_DMAR;
 209	else
 210		rw = OMAP2_MCSPI_CHCONF_DMAW;
 211
 212	if (enable)
 213		l |= rw;
 214	else
 215		l &= ~rw;
 216
 217	mcspi_write_chconf0(spi, l);
 218}
 219
 220static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 221{
 222	struct omap2_mcspi_cs *cs = spi->controller_state;
 223	u32 l;
 224
 225	l = cs->chctrl0;
 226	if (enable)
 227		l |= OMAP2_MCSPI_CHCTRL_EN;
 228	else
 229		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 230	cs->chctrl0 = l;
 231	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 232	/* Flash post-writes */
 233	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 234}
 235
 236static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 237{
 238	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 239	u32 l;
 240
 241	/* The controller handles the inverted chip selects
 242	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 243	 * the inversion from the core spi_set_cs function.
 244	 */
 245	if (spi->mode & SPI_CS_HIGH)
 246		enable = !enable;
 247
 248	if (spi->controller_state) {
 249		int err = pm_runtime_get_sync(mcspi->dev);
 250		if (err < 0) {
 251			pm_runtime_put_noidle(mcspi->dev);
 252			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 253			return;
 254		}
 255
 256		l = mcspi_cached_chconf0(spi);
 257
 258		if (enable)
 259			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 260		else
 261			l |= OMAP2_MCSPI_CHCONF_FORCE;
 262
 263		mcspi_write_chconf0(spi, l);
 264
 265		pm_runtime_mark_last_busy(mcspi->dev);
 266		pm_runtime_put_autosuspend(mcspi->dev);
 267	}
 268}
 269
 270static void omap2_mcspi_set_mode(struct spi_master *master)
 271{
 272	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 273	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 274	u32 l;
 275
 276	/*
 277	 * Choose master or slave mode
 278	 */
 279	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 280	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
 281	if (spi_controller_is_slave(master)) {
 282		l |= (OMAP2_MCSPI_MODULCTRL_MS);
 283	} else {
 284		l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
 285		l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 286	}
 287	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 288
 289	ctx->modulctrl = l;
 290}
 291
 292static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 293				struct spi_transfer *t, int enable)
 294{
 295	struct spi_master *master = spi->master;
 296	struct omap2_mcspi_cs *cs = spi->controller_state;
 297	struct omap2_mcspi *mcspi;
 298	unsigned int wcnt;
 299	int max_fifo_depth, bytes_per_word;
 300	u32 chconf, xferlevel;
 301
 302	mcspi = spi_master_get_devdata(master);
 303
 304	chconf = mcspi_cached_chconf0(spi);
 305	if (enable) {
 306		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 307		if (t->len % bytes_per_word != 0)
 308			goto disable_fifo;
 309
 310		if (t->rx_buf != NULL && t->tx_buf != NULL)
 311			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 312		else
 313			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 314
 315		wcnt = t->len / bytes_per_word;
 316		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 317			goto disable_fifo;
 318
 319		xferlevel = wcnt << 16;
 320		if (t->rx_buf != NULL) {
 321			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 322			xferlevel |= (bytes_per_word - 1) << 8;
 323		}
 324
 325		if (t->tx_buf != NULL) {
 326			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 327			xferlevel |= bytes_per_word - 1;
 328		}
 329
 330		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 331		mcspi_write_chconf0(spi, chconf);
 332		mcspi->fifo_depth = max_fifo_depth;
 333
 334		return;
 335	}
 336
 337disable_fifo:
 338	if (t->rx_buf != NULL)
 339		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 340
 341	if (t->tx_buf != NULL)
 342		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 343
 344	mcspi_write_chconf0(spi, chconf);
 345	mcspi->fifo_depth = 0;
 346}
 347
 348static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 349{
 350	unsigned long timeout;
 351
 352	timeout = jiffies + msecs_to_jiffies(1000);
 353	while (!(readl_relaxed(reg) & bit)) {
 354		if (time_after(jiffies, timeout)) {
 355			if (!(readl_relaxed(reg) & bit))
 356				return -ETIMEDOUT;
 357			else
 358				return 0;
 359		}
 360		cpu_relax();
 361	}
 362	return 0;
 363}
 364
 365static int mcspi_wait_for_completion(struct  omap2_mcspi *mcspi,
 366				     struct completion *x)
 367{
 368	if (spi_controller_is_slave(mcspi->master)) {
 369		if (wait_for_completion_interruptible(x) ||
 370		    mcspi->slave_aborted)
 371			return -EINTR;
 372	} else {
 373		wait_for_completion(x);
 374	}
 375
 376	return 0;
 377}
 378
 379static void omap2_mcspi_rx_callback(void *data)
 380{
 381	struct spi_device *spi = data;
 382	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 383	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 384
 385	/* We must disable the DMA RX request */
 386	omap2_mcspi_set_dma_req(spi, 1, 0);
 387
 388	complete(&mcspi_dma->dma_rx_completion);
 389}
 390
 391static void omap2_mcspi_tx_callback(void *data)
 392{
 393	struct spi_device *spi = data;
 394	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 395	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 396
 397	/* We must disable the DMA TX request */
 398	omap2_mcspi_set_dma_req(spi, 0, 0);
 399
 400	complete(&mcspi_dma->dma_tx_completion);
 401}
 402
 403static void omap2_mcspi_tx_dma(struct spi_device *spi,
 404				struct spi_transfer *xfer,
 405				struct dma_slave_config cfg)
 406{
 407	struct omap2_mcspi	*mcspi;
 408	struct omap2_mcspi_dma  *mcspi_dma;
 409	struct dma_async_tx_descriptor *tx;
 410
 411	mcspi = spi_master_get_devdata(spi->master);
 412	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 413
 414	dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 415
 416	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 417				     xfer->tx_sg.nents,
 418				     DMA_MEM_TO_DEV,
 419				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 420	if (tx) {
 421		tx->callback = omap2_mcspi_tx_callback;
 422		tx->callback_param = spi;
 423		dmaengine_submit(tx);
 424	} else {
 425		/* FIXME: fall back to PIO? */
 426	}
 427	dma_async_issue_pending(mcspi_dma->dma_tx);
 428	omap2_mcspi_set_dma_req(spi, 0, 1);
 429}
 430
 431static unsigned
 432omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 433				struct dma_slave_config cfg,
 434				unsigned es)
 435{
 436	struct omap2_mcspi	*mcspi;
 437	struct omap2_mcspi_dma  *mcspi_dma;
 438	unsigned int		count, transfer_reduction = 0;
 439	struct scatterlist	*sg_out[2];
 440	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 441	size_t			sizes[2];
 442	u32			l;
 443	int			elements = 0;
 444	int			word_len, element_count;
 445	struct omap2_mcspi_cs	*cs = spi->controller_state;
 446	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 447	struct dma_async_tx_descriptor *tx;
 448
 449	mcspi = spi_master_get_devdata(spi->master);
 450	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 451	count = xfer->len;
 452
 453	/*
 454	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 455	 *  it mentions reducing DMA transfer length by one element in master
 456	 *  normal mode.
 457	 */
 458	if (mcspi->fifo_depth == 0)
 459		transfer_reduction = es;
 460
 461	word_len = cs->word_len;
 462	l = mcspi_cached_chconf0(spi);
 463
 464	if (word_len <= 8)
 465		element_count = count;
 466	else if (word_len <= 16)
 467		element_count = count >> 1;
 468	else /* word_len <= 32 */
 469		element_count = count >> 2;
 470
 471
 472	dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 473
 474	/*
 475	 *  Reduce DMA transfer length by one more if McSPI is
 476	 *  configured in turbo mode.
 477	 */
 478	if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 479		transfer_reduction += es;
 480
 481	if (transfer_reduction) {
 482		/* Split sgl into two. The second sgl won't be used. */
 483		sizes[0] = count - transfer_reduction;
 484		sizes[1] = transfer_reduction;
 485		nb_sizes = 2;
 486	} else {
 487		/*
 488		 * Don't bother splitting the sgl. This essentially
 489		 * clones the original sgl.
 490		 */
 491		sizes[0] = count;
 492		nb_sizes = 1;
 493	}
 494
 495	ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
 496		       sizes, sg_out, out_mapped_nents, GFP_KERNEL);
 497
 498	if (ret < 0) {
 499		dev_err(&spi->dev, "sg_split failed\n");
 500		return 0;
 501	}
 502
 503	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
 504				     out_mapped_nents[0], DMA_DEV_TO_MEM,
 505				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 506	if (tx) {
 507		tx->callback = omap2_mcspi_rx_callback;
 508		tx->callback_param = spi;
 509		dmaengine_submit(tx);
 510	} else {
 511		/* FIXME: fall back to PIO? */
 512	}
 513
 514	dma_async_issue_pending(mcspi_dma->dma_rx);
 515	omap2_mcspi_set_dma_req(spi, 1, 1);
 516
 517	ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
 518	if (ret || mcspi->slave_aborted) {
 519		dmaengine_terminate_sync(mcspi_dma->dma_rx);
 520		omap2_mcspi_set_dma_req(spi, 1, 0);
 521		return 0;
 522	}
 523
 524	for (x = 0; x < nb_sizes; x++)
 525		kfree(sg_out[x]);
 526
 527	if (mcspi->fifo_depth > 0)
 528		return count;
 529
 530	/*
 531	 *  Due to the DMA transfer length reduction the missing bytes must
 532	 *  be read manually to receive all of the expected data.
 533	 */
 534	omap2_mcspi_set_enable(spi, 0);
 535
 536	elements = element_count - 1;
 537
 538	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 539		elements--;
 540
 541		if (!mcspi_wait_for_reg_bit(chstat_reg,
 542					    OMAP2_MCSPI_CHSTAT_RXS)) {
 543			u32 w;
 544
 545			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 546			if (word_len <= 8)
 547				((u8 *)xfer->rx_buf)[elements++] = w;
 548			else if (word_len <= 16)
 549				((u16 *)xfer->rx_buf)[elements++] = w;
 550			else /* word_len <= 32 */
 551				((u32 *)xfer->rx_buf)[elements++] = w;
 552		} else {
 553			int bytes_per_word = mcspi_bytes_per_word(word_len);
 554			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 555			count -= (bytes_per_word << 1);
 556			omap2_mcspi_set_enable(spi, 1);
 557			return count;
 558		}
 559	}
 560	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 561		u32 w;
 562
 563		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 564		if (word_len <= 8)
 565			((u8 *)xfer->rx_buf)[elements] = w;
 566		else if (word_len <= 16)
 567			((u16 *)xfer->rx_buf)[elements] = w;
 568		else /* word_len <= 32 */
 569			((u32 *)xfer->rx_buf)[elements] = w;
 570	} else {
 571		dev_err(&spi->dev, "DMA RX last word empty\n");
 572		count -= mcspi_bytes_per_word(word_len);
 573	}
 574	omap2_mcspi_set_enable(spi, 1);
 575	return count;
 576}
 577
 578static unsigned
 579omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 580{
 581	struct omap2_mcspi	*mcspi;
 582	struct omap2_mcspi_cs	*cs = spi->controller_state;
 583	struct omap2_mcspi_dma  *mcspi_dma;
 584	unsigned int		count;
 585	u8			*rx;
 586	const u8		*tx;
 587	struct dma_slave_config	cfg;
 588	enum dma_slave_buswidth width;
 589	unsigned es;
 590	void __iomem		*chstat_reg;
 591	void __iomem            *irqstat_reg;
 592	int			wait_res;
 593
 594	mcspi = spi_master_get_devdata(spi->master);
 595	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 596
 597	if (cs->word_len <= 8) {
 598		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 599		es = 1;
 600	} else if (cs->word_len <= 16) {
 601		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 602		es = 2;
 603	} else {
 604		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 605		es = 4;
 606	}
 607
 608	count = xfer->len;
 609
 610	memset(&cfg, 0, sizeof(cfg));
 611	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 612	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 613	cfg.src_addr_width = width;
 614	cfg.dst_addr_width = width;
 615	cfg.src_maxburst = 1;
 616	cfg.dst_maxburst = 1;
 617
 618	rx = xfer->rx_buf;
 619	tx = xfer->tx_buf;
 620
 621	mcspi->slave_aborted = false;
 622	reinit_completion(&mcspi_dma->dma_tx_completion);
 623	reinit_completion(&mcspi_dma->dma_rx_completion);
 624	reinit_completion(&mcspi->txdone);
 625	if (tx) {
 626		/* Enable EOW IRQ to know end of tx in slave mode */
 627		if (spi_controller_is_slave(spi->master))
 628			mcspi_write_reg(spi->master,
 629					OMAP2_MCSPI_IRQENABLE,
 630					OMAP2_MCSPI_IRQSTATUS_EOW);
 631		omap2_mcspi_tx_dma(spi, xfer, cfg);
 632	}
 633
 634	if (rx != NULL)
 635		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 636
 637	if (tx != NULL) {
 638		int ret;
 639
 640		ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
 641		if (ret || mcspi->slave_aborted) {
 642			dmaengine_terminate_sync(mcspi_dma->dma_tx);
 643			omap2_mcspi_set_dma_req(spi, 0, 0);
 644			return 0;
 645		}
 646
 647		if (spi_controller_is_slave(mcspi->master)) {
 648			ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
 649			if (ret || mcspi->slave_aborted)
 650				return 0;
 651		}
 652
 653		if (mcspi->fifo_depth > 0) {
 654			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 655
 656			if (mcspi_wait_for_reg_bit(irqstat_reg,
 657						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 658				dev_err(&spi->dev, "EOW timed out\n");
 659
 660			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 661					OMAP2_MCSPI_IRQSTATUS_EOW);
 662		}
 663
 664		/* for TX_ONLY mode, be sure all words have shifted out */
 665		if (rx == NULL) {
 666			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 667			if (mcspi->fifo_depth > 0) {
 668				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 669						OMAP2_MCSPI_CHSTAT_TXFFE);
 670				if (wait_res < 0)
 671					dev_err(&spi->dev, "TXFFE timed out\n");
 672			} else {
 673				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 674						OMAP2_MCSPI_CHSTAT_TXS);
 675				if (wait_res < 0)
 676					dev_err(&spi->dev, "TXS timed out\n");
 677			}
 678			if (wait_res >= 0 &&
 679				(mcspi_wait_for_reg_bit(chstat_reg,
 680					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 681				dev_err(&spi->dev, "EOT timed out\n");
 682		}
 683	}
 684	return count;
 685}
 686
 687static unsigned
 688omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 689{
 690	struct omap2_mcspi_cs	*cs = spi->controller_state;
 691	unsigned int		count, c;
 692	u32			l;
 693	void __iomem		*base = cs->base;
 694	void __iomem		*tx_reg;
 695	void __iomem		*rx_reg;
 696	void __iomem		*chstat_reg;
 697	int			word_len;
 698
 699	count = xfer->len;
 700	c = count;
 701	word_len = cs->word_len;
 702
 703	l = mcspi_cached_chconf0(spi);
 704
 705	/* We store the pre-calculated register addresses on stack to speed
 706	 * up the transfer loop. */
 707	tx_reg		= base + OMAP2_MCSPI_TX0;
 708	rx_reg		= base + OMAP2_MCSPI_RX0;
 709	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 710
 711	if (c < (word_len>>3))
 712		return 0;
 713
 714	if (word_len <= 8) {
 715		u8		*rx;
 716		const u8	*tx;
 717
 718		rx = xfer->rx_buf;
 719		tx = xfer->tx_buf;
 720
 721		do {
 722			c -= 1;
 723			if (tx != NULL) {
 724				if (mcspi_wait_for_reg_bit(chstat_reg,
 725						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 726					dev_err(&spi->dev, "TXS timed out\n");
 727					goto out;
 728				}
 729				dev_vdbg(&spi->dev, "write-%d %02x\n",
 730						word_len, *tx);
 731				writel_relaxed(*tx++, tx_reg);
 732			}
 733			if (rx != NULL) {
 734				if (mcspi_wait_for_reg_bit(chstat_reg,
 735						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 736					dev_err(&spi->dev, "RXS timed out\n");
 737					goto out;
 738				}
 739
 740				if (c == 1 && tx == NULL &&
 741				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 742					omap2_mcspi_set_enable(spi, 0);
 743					*rx++ = readl_relaxed(rx_reg);
 744					dev_vdbg(&spi->dev, "read-%d %02x\n",
 745						    word_len, *(rx - 1));
 746					if (mcspi_wait_for_reg_bit(chstat_reg,
 747						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 748						dev_err(&spi->dev,
 749							"RXS timed out\n");
 750						goto out;
 751					}
 752					c = 0;
 753				} else if (c == 0 && tx == NULL) {
 754					omap2_mcspi_set_enable(spi, 0);
 755				}
 756
 757				*rx++ = readl_relaxed(rx_reg);
 758				dev_vdbg(&spi->dev, "read-%d %02x\n",
 759						word_len, *(rx - 1));
 760			}
 
 
 761		} while (c);
 762	} else if (word_len <= 16) {
 763		u16		*rx;
 764		const u16	*tx;
 765
 766		rx = xfer->rx_buf;
 767		tx = xfer->tx_buf;
 768		do {
 769			c -= 2;
 770			if (tx != NULL) {
 771				if (mcspi_wait_for_reg_bit(chstat_reg,
 772						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 773					dev_err(&spi->dev, "TXS timed out\n");
 774					goto out;
 775				}
 776				dev_vdbg(&spi->dev, "write-%d %04x\n",
 777						word_len, *tx);
 778				writel_relaxed(*tx++, tx_reg);
 779			}
 780			if (rx != NULL) {
 781				if (mcspi_wait_for_reg_bit(chstat_reg,
 782						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 783					dev_err(&spi->dev, "RXS timed out\n");
 784					goto out;
 785				}
 786
 787				if (c == 2 && tx == NULL &&
 788				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 789					omap2_mcspi_set_enable(spi, 0);
 790					*rx++ = readl_relaxed(rx_reg);
 791					dev_vdbg(&spi->dev, "read-%d %04x\n",
 792						    word_len, *(rx - 1));
 793					if (mcspi_wait_for_reg_bit(chstat_reg,
 794						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 795						dev_err(&spi->dev,
 796							"RXS timed out\n");
 797						goto out;
 798					}
 799					c = 0;
 800				} else if (c == 0 && tx == NULL) {
 801					omap2_mcspi_set_enable(spi, 0);
 802				}
 803
 804				*rx++ = readl_relaxed(rx_reg);
 805				dev_vdbg(&spi->dev, "read-%d %04x\n",
 806						word_len, *(rx - 1));
 807			}
 
 
 808		} while (c >= 2);
 809	} else if (word_len <= 32) {
 810		u32		*rx;
 811		const u32	*tx;
 812
 813		rx = xfer->rx_buf;
 814		tx = xfer->tx_buf;
 815		do {
 816			c -= 4;
 817			if (tx != NULL) {
 818				if (mcspi_wait_for_reg_bit(chstat_reg,
 819						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 820					dev_err(&spi->dev, "TXS timed out\n");
 821					goto out;
 822				}
 823				dev_vdbg(&spi->dev, "write-%d %08x\n",
 824						word_len, *tx);
 825				writel_relaxed(*tx++, tx_reg);
 826			}
 827			if (rx != NULL) {
 828				if (mcspi_wait_for_reg_bit(chstat_reg,
 829						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 830					dev_err(&spi->dev, "RXS timed out\n");
 831					goto out;
 832				}
 833
 834				if (c == 4 && tx == NULL &&
 835				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 836					omap2_mcspi_set_enable(spi, 0);
 837					*rx++ = readl_relaxed(rx_reg);
 838					dev_vdbg(&spi->dev, "read-%d %08x\n",
 839						    word_len, *(rx - 1));
 840					if (mcspi_wait_for_reg_bit(chstat_reg,
 841						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 842						dev_err(&spi->dev,
 843							"RXS timed out\n");
 844						goto out;
 845					}
 846					c = 0;
 847				} else if (c == 0 && tx == NULL) {
 848					omap2_mcspi_set_enable(spi, 0);
 849				}
 850
 851				*rx++ = readl_relaxed(rx_reg);
 852				dev_vdbg(&spi->dev, "read-%d %08x\n",
 853						word_len, *(rx - 1));
 854			}
 
 
 855		} while (c >= 4);
 856	}
 857
 858	/* for TX_ONLY mode, be sure all words have shifted out */
 859	if (xfer->rx_buf == NULL) {
 860		if (mcspi_wait_for_reg_bit(chstat_reg,
 861				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 862			dev_err(&spi->dev, "TXS timed out\n");
 863		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 864				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 865			dev_err(&spi->dev, "EOT timed out\n");
 866
 867		/* disable chan to purge rx datas received in TX_ONLY transfer,
 868		 * otherwise these rx datas will affect the direct following
 869		 * RX_ONLY transfer.
 870		 */
 871		omap2_mcspi_set_enable(spi, 0);
 872	}
 873out:
 874	omap2_mcspi_set_enable(spi, 1);
 875	return count - c;
 876}
 877
 878static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 879{
 880	u32 div;
 881
 882	for (div = 0; div < 15; div++)
 883		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 884			return div;
 885
 886	return 15;
 887}
 888
 889/* called only when no transfer is active to this device */
 890static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 891		struct spi_transfer *t)
 892{
 893	struct omap2_mcspi_cs *cs = spi->controller_state;
 894	struct omap2_mcspi *mcspi;
 895	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 896	u8 word_len = spi->bits_per_word;
 897	u32 speed_hz = spi->max_speed_hz;
 898
 899	mcspi = spi_master_get_devdata(spi->master);
 900
 901	if (t != NULL && t->bits_per_word)
 902		word_len = t->bits_per_word;
 903
 904	cs->word_len = word_len;
 905
 906	if (t && t->speed_hz)
 907		speed_hz = t->speed_hz;
 908
 909	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 910	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 911		clkd = omap2_mcspi_calc_divisor(speed_hz);
 912		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 913		clkg = 0;
 914	} else {
 915		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 916		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 917		clkd = (div - 1) & 0xf;
 918		extclk = (div - 1) >> 4;
 919		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 920	}
 921
 922	l = mcspi_cached_chconf0(spi);
 923
 924	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 925	 * REVISIT: this controller could support SPI_3WIRE mode.
 926	 */
 927	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 928		l &= ~OMAP2_MCSPI_CHCONF_IS;
 929		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 930		l |= OMAP2_MCSPI_CHCONF_DPE0;
 931	} else {
 932		l |= OMAP2_MCSPI_CHCONF_IS;
 933		l |= OMAP2_MCSPI_CHCONF_DPE1;
 934		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 935	}
 936
 937	/* wordlength */
 938	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 939	l |= (word_len - 1) << 7;
 940
 941	/* set chipselect polarity; manage with FORCE */
 942	if (!(spi->mode & SPI_CS_HIGH))
 943		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 944	else
 945		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 946
 947	/* set clock divisor */
 948	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 949	l |= clkd << 2;
 950
 951	/* set clock granularity */
 952	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 953	l |= clkg;
 954	if (clkg) {
 955		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 956		cs->chctrl0 |= extclk << 8;
 957		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 958	}
 959
 960	/* set SPI mode 0..3 */
 961	if (spi->mode & SPI_CPOL)
 962		l |= OMAP2_MCSPI_CHCONF_POL;
 963	else
 964		l &= ~OMAP2_MCSPI_CHCONF_POL;
 965	if (spi->mode & SPI_CPHA)
 966		l |= OMAP2_MCSPI_CHCONF_PHA;
 967	else
 968		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 969
 970	mcspi_write_chconf0(spi, l);
 971
 972	cs->mode = spi->mode;
 973
 974	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 975			speed_hz,
 976			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 977			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 978
 979	return 0;
 980}
 981
 982/*
 983 * Note that we currently allow DMA only if we get a channel
 984 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 985 */
 986static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
 987				   struct omap2_mcspi_dma *mcspi_dma)
 988{
 989	int ret = 0;
 990
 991	mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
 992					     mcspi_dma->dma_rx_ch_name);
 993	if (IS_ERR(mcspi_dma->dma_rx)) {
 994		ret = PTR_ERR(mcspi_dma->dma_rx);
 995		mcspi_dma->dma_rx = NULL;
 996		goto no_dma;
 997	}
 998
 999	mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
1000					     mcspi_dma->dma_tx_ch_name);
1001	if (IS_ERR(mcspi_dma->dma_tx)) {
1002		ret = PTR_ERR(mcspi_dma->dma_tx);
1003		mcspi_dma->dma_tx = NULL;
1004		dma_release_channel(mcspi_dma->dma_rx);
1005		mcspi_dma->dma_rx = NULL;
1006	}
1007
1008	init_completion(&mcspi_dma->dma_rx_completion);
1009	init_completion(&mcspi_dma->dma_tx_completion);
1010
1011no_dma:
1012	return ret;
1013}
1014
1015static void omap2_mcspi_release_dma(struct spi_master *master)
1016{
1017	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1018	struct omap2_mcspi_dma	*mcspi_dma;
1019	int i;
1020
1021	for (i = 0; i < master->num_chipselect; i++) {
1022		mcspi_dma = &mcspi->dma_channels[i];
1023
1024		if (mcspi_dma->dma_rx) {
1025			dma_release_channel(mcspi_dma->dma_rx);
1026			mcspi_dma->dma_rx = NULL;
1027		}
1028		if (mcspi_dma->dma_tx) {
1029			dma_release_channel(mcspi_dma->dma_tx);
1030			mcspi_dma->dma_tx = NULL;
1031		}
1032	}
1033}
1034
1035static void omap2_mcspi_cleanup(struct spi_device *spi)
1036{
1037	struct omap2_mcspi_cs	*cs;
1038
1039	if (spi->controller_state) {
1040		/* Unlink controller state from context save list */
1041		cs = spi->controller_state;
1042		list_del(&cs->node);
1043
1044		kfree(cs);
1045	}
1046}
1047
1048static int omap2_mcspi_setup(struct spi_device *spi)
1049{
1050	bool			initial_setup = false;
1051	int			ret;
1052	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
1053	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1054	struct omap2_mcspi_cs	*cs = spi->controller_state;
1055
1056	if (!cs) {
1057		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1058		if (!cs)
1059			return -ENOMEM;
1060		cs->base = mcspi->base + spi->chip_select * 0x14;
1061		cs->phys = mcspi->phys + spi->chip_select * 0x14;
1062		cs->mode = 0;
1063		cs->chconf0 = 0;
1064		cs->chctrl0 = 0;
1065		spi->controller_state = cs;
1066		/* Link this to context save list */
1067		list_add_tail(&cs->node, &ctx->cs);
1068		initial_setup = true;
1069	}
1070
1071	ret = pm_runtime_get_sync(mcspi->dev);
1072	if (ret < 0) {
1073		pm_runtime_put_noidle(mcspi->dev);
1074		if (initial_setup)
1075			omap2_mcspi_cleanup(spi);
1076
1077		return ret;
1078	}
1079
1080	ret = omap2_mcspi_setup_transfer(spi, NULL);
1081	if (ret && initial_setup)
1082		omap2_mcspi_cleanup(spi);
1083
1084	pm_runtime_mark_last_busy(mcspi->dev);
1085	pm_runtime_put_autosuspend(mcspi->dev);
1086
1087	return ret;
1088}
1089
1090static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1091{
1092	struct omap2_mcspi *mcspi = data;
1093	u32 irqstat;
1094
1095	irqstat	= mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1096	if (!irqstat)
1097		return IRQ_NONE;
1098
1099	/* Disable IRQ and wakeup slave xfer task */
1100	mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1101	if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1102		complete(&mcspi->txdone);
1103
1104	return IRQ_HANDLED;
1105}
1106
1107static int omap2_mcspi_slave_abort(struct spi_master *master)
1108{
1109	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1110	struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1111
1112	mcspi->slave_aborted = true;
1113	complete(&mcspi_dma->dma_rx_completion);
1114	complete(&mcspi_dma->dma_tx_completion);
1115	complete(&mcspi->txdone);
1116
1117	return 0;
1118}
1119
1120static int omap2_mcspi_transfer_one(struct spi_master *master,
1121				    struct spi_device *spi,
1122				    struct spi_transfer *t)
1123{
1124
1125	/* We only enable one channel at a time -- the one whose message is
1126	 * -- although this controller would gladly
1127	 * arbitrate among multiple channels.  This corresponds to "single
1128	 * channel" master mode.  As a side effect, we need to manage the
1129	 * chipselect with the FORCE bit ... CS != channel enable.
1130	 */
1131
1132	struct omap2_mcspi		*mcspi;
1133	struct omap2_mcspi_dma		*mcspi_dma;
1134	struct omap2_mcspi_cs		*cs;
1135	struct omap2_mcspi_device_config *cd;
1136	int				par_override = 0;
1137	int				status = 0;
1138	u32				chconf;
1139
1140	mcspi = spi_master_get_devdata(master);
1141	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1142	cs = spi->controller_state;
1143	cd = spi->controller_data;
1144
1145	/*
1146	 * The slave driver could have changed spi->mode in which case
1147	 * it will be different from cs->mode (the current hardware setup).
1148	 * If so, set par_override (even though its not a parity issue) so
1149	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1150	 * with the correct mode on the first iteration of the loop below.
1151	 */
1152	if (spi->mode != cs->mode)
1153		par_override = 1;
1154
1155	omap2_mcspi_set_enable(spi, 0);
1156
1157	if (spi->cs_gpiod)
1158		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1159
1160	if (par_override ||
1161	    (t->speed_hz != spi->max_speed_hz) ||
1162	    (t->bits_per_word != spi->bits_per_word)) {
1163		par_override = 1;
1164		status = omap2_mcspi_setup_transfer(spi, t);
1165		if (status < 0)
1166			goto out;
1167		if (t->speed_hz == spi->max_speed_hz &&
1168		    t->bits_per_word == spi->bits_per_word)
1169			par_override = 0;
1170	}
1171	if (cd && cd->cs_per_word) {
1172		chconf = mcspi->ctx.modulctrl;
1173		chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1174		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1175		mcspi->ctx.modulctrl =
1176			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1177	}
1178
1179	chconf = mcspi_cached_chconf0(spi);
1180	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1181	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1182
1183	if (t->tx_buf == NULL)
1184		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1185	else if (t->rx_buf == NULL)
1186		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1187
1188	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1189		/* Turbo mode is for more than one word */
1190		if (t->len > ((cs->word_len + 7) >> 3))
1191			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1192	}
1193
1194	mcspi_write_chconf0(spi, chconf);
1195
1196	if (t->len) {
1197		unsigned	count;
1198
1199		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1200		    master->cur_msg_mapped &&
1201		    master->can_dma(master, spi, t))
1202			omap2_mcspi_set_fifo(spi, t, 1);
1203
1204		omap2_mcspi_set_enable(spi, 1);
1205
1206		/* RX_ONLY mode needs dummy data in TX reg */
1207		if (t->tx_buf == NULL)
1208			writel_relaxed(0, cs->base
1209					+ OMAP2_MCSPI_TX0);
1210
1211		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1212		    master->cur_msg_mapped &&
1213		    master->can_dma(master, spi, t))
1214			count = omap2_mcspi_txrx_dma(spi, t);
1215		else
1216			count = omap2_mcspi_txrx_pio(spi, t);
1217
1218		if (count != t->len) {
1219			status = -EIO;
1220			goto out;
1221		}
1222	}
1223
1224	omap2_mcspi_set_enable(spi, 0);
1225
1226	if (mcspi->fifo_depth > 0)
1227		omap2_mcspi_set_fifo(spi, t, 0);
1228
1229out:
1230	/* Restore defaults if they were overriden */
1231	if (par_override) {
1232		par_override = 0;
1233		status = omap2_mcspi_setup_transfer(spi, NULL);
1234	}
1235
1236	if (cd && cd->cs_per_word) {
1237		chconf = mcspi->ctx.modulctrl;
1238		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1239		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1240		mcspi->ctx.modulctrl =
1241			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1242	}
1243
1244	omap2_mcspi_set_enable(spi, 0);
1245
1246	if (spi->cs_gpiod)
1247		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1248
1249	if (mcspi->fifo_depth > 0 && t)
1250		omap2_mcspi_set_fifo(spi, t, 0);
1251
1252	return status;
1253}
1254
1255static int omap2_mcspi_prepare_message(struct spi_master *master,
1256				       struct spi_message *msg)
1257{
1258	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1259	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1260	struct omap2_mcspi_cs	*cs;
1261
1262	/* Only a single channel can have the FORCE bit enabled
1263	 * in its chconf0 register.
1264	 * Scan all channels and disable them except the current one.
1265	 * A FORCE can remain from a last transfer having cs_change enabled
1266	 */
1267	list_for_each_entry(cs, &ctx->cs, node) {
1268		if (msg->spi->controller_state == cs)
1269			continue;
1270
1271		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1272			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1273			writel_relaxed(cs->chconf0,
1274					cs->base + OMAP2_MCSPI_CHCONF0);
1275			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1276		}
1277	}
1278
1279	return 0;
1280}
1281
1282static bool omap2_mcspi_can_dma(struct spi_master *master,
1283				struct spi_device *spi,
1284				struct spi_transfer *xfer)
1285{
1286	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1287	struct omap2_mcspi_dma *mcspi_dma =
1288		&mcspi->dma_channels[spi->chip_select];
1289
1290	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1291		return false;
1292
1293	if (spi_controller_is_slave(master))
1294		return true;
1295
1296	master->dma_rx = mcspi_dma->dma_rx;
1297	master->dma_tx = mcspi_dma->dma_tx;
1298
1299	return (xfer->len >= DMA_MIN_BYTES);
1300}
1301
1302static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1303{
1304	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1305	struct omap2_mcspi_dma *mcspi_dma =
1306		&mcspi->dma_channels[spi->chip_select];
1307
1308	if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1309		return mcspi->max_xfer_len;
1310
1311	return SIZE_MAX;
1312}
1313
1314static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1315{
1316	struct spi_master	*master = mcspi->master;
1317	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1318	int			ret = 0;
1319
1320	ret = pm_runtime_get_sync(mcspi->dev);
1321	if (ret < 0) {
1322		pm_runtime_put_noidle(mcspi->dev);
1323
1324		return ret;
1325	}
1326
1327	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1328			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1329	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1330
1331	omap2_mcspi_set_mode(master);
1332	pm_runtime_mark_last_busy(mcspi->dev);
1333	pm_runtime_put_autosuspend(mcspi->dev);
1334	return 0;
1335}
1336
1337static int omap_mcspi_runtime_suspend(struct device *dev)
1338{
1339	int error;
1340
1341	error = pinctrl_pm_select_idle_state(dev);
1342	if (error)
1343		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1344
1345	return 0;
1346}
1347
1348/*
1349 * When SPI wake up from off-mode, CS is in activate state. If it was in
1350 * inactive state when driver was suspend, then force it to inactive state at
1351 * wake up.
1352 */
1353static int omap_mcspi_runtime_resume(struct device *dev)
1354{
1355	struct spi_master *master = dev_get_drvdata(dev);
1356	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1357	struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1358	struct omap2_mcspi_cs *cs;
1359	int error;
1360
1361	error = pinctrl_pm_select_default_state(dev);
1362	if (error)
1363		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1364
1365	/* McSPI: context restore */
1366	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1367	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1368
1369	list_for_each_entry(cs, &ctx->cs, node) {
1370		/*
1371		 * We need to toggle CS state for OMAP take this
1372		 * change in account.
1373		 */
1374		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1375			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1376			writel_relaxed(cs->chconf0,
1377				       cs->base + OMAP2_MCSPI_CHCONF0);
1378			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1379			writel_relaxed(cs->chconf0,
1380				       cs->base + OMAP2_MCSPI_CHCONF0);
1381		} else {
1382			writel_relaxed(cs->chconf0,
1383				       cs->base + OMAP2_MCSPI_CHCONF0);
1384		}
1385	}
1386
1387	return 0;
1388}
1389
1390static struct omap2_mcspi_platform_config omap2_pdata = {
1391	.regs_offset = 0,
1392};
1393
1394static struct omap2_mcspi_platform_config omap4_pdata = {
1395	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1396};
1397
1398static struct omap2_mcspi_platform_config am654_pdata = {
1399	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1400	.max_xfer_len = SZ_4K - 1,
1401};
1402
1403static const struct of_device_id omap_mcspi_of_match[] = {
1404	{
1405		.compatible = "ti,omap2-mcspi",
1406		.data = &omap2_pdata,
1407	},
1408	{
1409		.compatible = "ti,omap4-mcspi",
1410		.data = &omap4_pdata,
1411	},
1412	{
1413		.compatible = "ti,am654-mcspi",
1414		.data = &am654_pdata,
1415	},
1416	{ },
1417};
1418MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1419
1420static int omap2_mcspi_probe(struct platform_device *pdev)
1421{
1422	struct spi_master	*master;
1423	const struct omap2_mcspi_platform_config *pdata;
1424	struct omap2_mcspi	*mcspi;
1425	struct resource		*r;
1426	int			status = 0, i;
1427	u32			regs_offset = 0;
1428	struct device_node	*node = pdev->dev.of_node;
1429	const struct of_device_id *match;
1430
1431	if (of_property_read_bool(node, "spi-slave"))
1432		master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1433	else
1434		master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1435	if (!master)
1436		return -ENOMEM;
1437
1438	/* the spi->mode bits understood by this driver: */
1439	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1440	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1441	master->setup = omap2_mcspi_setup;
1442	master->auto_runtime_pm = true;
1443	master->prepare_message = omap2_mcspi_prepare_message;
1444	master->can_dma = omap2_mcspi_can_dma;
1445	master->transfer_one = omap2_mcspi_transfer_one;
1446	master->set_cs = omap2_mcspi_set_cs;
1447	master->cleanup = omap2_mcspi_cleanup;
1448	master->slave_abort = omap2_mcspi_slave_abort;
1449	master->dev.of_node = node;
1450	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1451	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1452	master->use_gpio_descriptors = true;
1453
1454	platform_set_drvdata(pdev, master);
1455
1456	mcspi = spi_master_get_devdata(master);
1457	mcspi->master = master;
1458
1459	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1460	if (match) {
1461		u32 num_cs = 1; /* default number of chipselect */
1462		pdata = match->data;
1463
1464		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1465		master->num_chipselect = num_cs;
1466		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1467			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1468	} else {
1469		pdata = dev_get_platdata(&pdev->dev);
1470		master->num_chipselect = pdata->num_cs;
1471		mcspi->pin_dir = pdata->pin_dir;
1472	}
1473	regs_offset = pdata->regs_offset;
1474	if (pdata->max_xfer_len) {
1475		mcspi->max_xfer_len = pdata->max_xfer_len;
1476		master->max_transfer_size = omap2_mcspi_max_xfer_size;
1477	}
1478
1479	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1480	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1481	if (IS_ERR(mcspi->base)) {
1482		status = PTR_ERR(mcspi->base);
1483		goto free_master;
1484	}
1485	mcspi->phys = r->start + regs_offset;
1486	mcspi->base += regs_offset;
1487
1488	mcspi->dev = &pdev->dev;
1489
1490	INIT_LIST_HEAD(&mcspi->ctx.cs);
1491
1492	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1493					   sizeof(struct omap2_mcspi_dma),
1494					   GFP_KERNEL);
1495	if (mcspi->dma_channels == NULL) {
1496		status = -ENOMEM;
1497		goto free_master;
1498	}
1499
1500	for (i = 0; i < master->num_chipselect; i++) {
1501		sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1502		sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1503
1504		status = omap2_mcspi_request_dma(mcspi,
1505						 &mcspi->dma_channels[i]);
1506		if (status == -EPROBE_DEFER)
1507			goto free_master;
1508	}
1509
1510	status = platform_get_irq(pdev, 0);
1511	if (status == -EPROBE_DEFER)
1512		goto free_master;
1513	if (status < 0) {
1514		dev_err(&pdev->dev, "no irq resource found\n");
1515		goto free_master;
1516	}
1517	init_completion(&mcspi->txdone);
1518	status = devm_request_irq(&pdev->dev, status,
1519				  omap2_mcspi_irq_handler, 0, pdev->name,
1520				  mcspi);
1521	if (status) {
1522		dev_err(&pdev->dev, "Cannot request IRQ");
1523		goto free_master;
1524	}
1525
1526	pm_runtime_use_autosuspend(&pdev->dev);
1527	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1528	pm_runtime_enable(&pdev->dev);
1529
1530	status = omap2_mcspi_controller_setup(mcspi);
1531	if (status < 0)
1532		goto disable_pm;
1533
1534	status = devm_spi_register_controller(&pdev->dev, master);
1535	if (status < 0)
1536		goto disable_pm;
1537
1538	return status;
1539
1540disable_pm:
1541	pm_runtime_dont_use_autosuspend(&pdev->dev);
1542	pm_runtime_put_sync(&pdev->dev);
1543	pm_runtime_disable(&pdev->dev);
1544free_master:
1545	omap2_mcspi_release_dma(master);
1546	spi_master_put(master);
1547	return status;
1548}
1549
1550static int omap2_mcspi_remove(struct platform_device *pdev)
1551{
1552	struct spi_master *master = platform_get_drvdata(pdev);
1553	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1554
1555	omap2_mcspi_release_dma(master);
1556
1557	pm_runtime_dont_use_autosuspend(mcspi->dev);
1558	pm_runtime_put_sync(mcspi->dev);
1559	pm_runtime_disable(&pdev->dev);
1560
1561	return 0;
1562}
1563
1564/* work with hotplug and coldplug */
1565MODULE_ALIAS("platform:omap2_mcspi");
1566
1567static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1568{
1569	struct spi_master *master = dev_get_drvdata(dev);
1570	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1571	int error;
1572
1573	error = pinctrl_pm_select_sleep_state(dev);
1574	if (error)
1575		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1576			 __func__, error);
1577
1578	error = spi_master_suspend(master);
1579	if (error)
1580		dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1581			 __func__, error);
1582
1583	return pm_runtime_force_suspend(dev);
1584}
1585
1586static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1587{
1588	struct spi_master *master = dev_get_drvdata(dev);
1589	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1590	int error;
1591
1592	error = spi_master_resume(master);
1593	if (error)
1594		dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1595			 __func__, error);
1596
1597	return pm_runtime_force_resume(dev);
1598}
1599
1600static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1601	SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1602				omap2_mcspi_resume)
1603	.runtime_suspend	= omap_mcspi_runtime_suspend,
1604	.runtime_resume		= omap_mcspi_runtime_resume,
1605};
1606
1607static struct platform_driver omap2_mcspi_driver = {
1608	.driver = {
1609		.name =		"omap2_mcspi",
1610		.pm =		&omap2_mcspi_pm_ops,
1611		.of_match_table = omap_mcspi_of_match,
1612	},
1613	.probe =	omap2_mcspi_probe,
1614	.remove =	omap2_mcspi_remove,
1615};
1616
1617module_platform_driver(omap2_mcspi_driver);
1618MODULE_LICENSE("GPL");