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v6.9.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * OMAP2 McSPI controller driver
   4 *
   5 * Copyright (C) 2005, 2006 Nokia Corporation
   6 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   7 *		Juha 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_controller	*ctlr;
 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	struct clk		*ref_clk;
 129	int			fifo_depth;
 130	bool			target_aborted;
 131	unsigned int		pin_dir:1;
 132	size_t			max_xfer_len;
 133	u32			ref_clk_hz;
 134};
 135
 136struct omap2_mcspi_cs {
 137	void __iomem		*base;
 138	unsigned long		phys;
 139	int			word_len;
 140	u16			mode;
 141	struct list_head	node;
 142	/* Context save and restore shadow register */
 143	u32			chconf0, chctrl0;
 144};
 145
 146static inline void mcspi_write_reg(struct spi_controller *ctlr,
 147		int idx, u32 val)
 148{
 149	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
 150
 151	writel_relaxed(val, mcspi->base + idx);
 152}
 153
 154static inline u32 mcspi_read_reg(struct spi_controller *ctlr, int idx)
 155{
 156	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
 157
 158	return readl_relaxed(mcspi->base + idx);
 159}
 160
 161static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 162		int idx, u32 val)
 163{
 164	struct omap2_mcspi_cs	*cs = spi->controller_state;
 165
 166	writel_relaxed(val, cs->base +  idx);
 167}
 168
 169static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 170{
 171	struct omap2_mcspi_cs	*cs = spi->controller_state;
 172
 173	return readl_relaxed(cs->base + idx);
 174}
 175
 176static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 177{
 178	struct omap2_mcspi_cs *cs = spi->controller_state;
 179
 180	return cs->chconf0;
 181}
 182
 183static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 184{
 185	struct omap2_mcspi_cs *cs = spi->controller_state;
 186
 187	cs->chconf0 = val;
 188	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 189	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 190}
 191
 192static inline int mcspi_bytes_per_word(int word_len)
 193{
 194	if (word_len <= 8)
 195		return 1;
 196	else if (word_len <= 16)
 197		return 2;
 198	else /* word_len <= 32 */
 199		return 4;
 200}
 201
 202static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 203		int is_read, int enable)
 204{
 205	u32 l, rw;
 206
 207	l = mcspi_cached_chconf0(spi);
 208
 209	if (is_read) /* 1 is read, 0 write */
 210		rw = OMAP2_MCSPI_CHCONF_DMAR;
 211	else
 212		rw = OMAP2_MCSPI_CHCONF_DMAW;
 213
 214	if (enable)
 215		l |= rw;
 216	else
 217		l &= ~rw;
 218
 219	mcspi_write_chconf0(spi, l);
 220}
 221
 222static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 223{
 224	struct omap2_mcspi_cs *cs = spi->controller_state;
 225	u32 l;
 226
 227	l = cs->chctrl0;
 228	if (enable)
 229		l |= OMAP2_MCSPI_CHCTRL_EN;
 230	else
 231		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 232	cs->chctrl0 = l;
 233	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 234	/* Flash post-writes */
 235	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 236}
 237
 238static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 239{
 240	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
 241	u32 l;
 242
 243	/* The controller handles the inverted chip selects
 244	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 245	 * the inversion from the core spi_set_cs function.
 246	 */
 247	if (spi->mode & SPI_CS_HIGH)
 248		enable = !enable;
 249
 250	if (spi->controller_state) {
 251		int err = pm_runtime_resume_and_get(mcspi->dev);
 252		if (err < 0) {
 253			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 254			return;
 255		}
 256
 257		l = mcspi_cached_chconf0(spi);
 258
 259		if (enable)
 260			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 261		else
 262			l |= OMAP2_MCSPI_CHCONF_FORCE;
 263
 264		mcspi_write_chconf0(spi, l);
 265
 266		pm_runtime_mark_last_busy(mcspi->dev);
 267		pm_runtime_put_autosuspend(mcspi->dev);
 268	}
 269}
 270
 271static void omap2_mcspi_set_mode(struct spi_controller *ctlr)
 272{
 273	struct omap2_mcspi	*mcspi = spi_controller_get_devdata(ctlr);
 274	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 275	u32 l;
 276
 277	/*
 278	 * Choose host or target mode
 279	 */
 280	l = mcspi_read_reg(ctlr, OMAP2_MCSPI_MODULCTRL);
 281	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
 282	if (spi_controller_is_target(ctlr)) {
 283		l |= (OMAP2_MCSPI_MODULCTRL_MS);
 284	} else {
 285		l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
 286		l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 287	}
 288	mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, l);
 289
 290	ctx->modulctrl = l;
 291}
 292
 293static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 294				struct spi_transfer *t, int enable)
 295{
 296	struct spi_controller *ctlr = spi->controller;
 297	struct omap2_mcspi_cs *cs = spi->controller_state;
 298	struct omap2_mcspi *mcspi;
 299	unsigned int wcnt;
 300	int max_fifo_depth, bytes_per_word;
 301	u32 chconf, xferlevel;
 302
 303	mcspi = spi_controller_get_devdata(ctlr);
 304
 305	chconf = mcspi_cached_chconf0(spi);
 306	if (enable) {
 307		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 308		if (t->len % bytes_per_word != 0)
 309			goto disable_fifo;
 310
 311		if (t->rx_buf != NULL && t->tx_buf != NULL)
 312			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 313		else
 314			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 315
 316		wcnt = t->len / bytes_per_word;
 317		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 318			goto disable_fifo;
 319
 320		xferlevel = wcnt << 16;
 321		if (t->rx_buf != NULL) {
 322			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 323			xferlevel |= (bytes_per_word - 1) << 8;
 324		}
 325
 326		if (t->tx_buf != NULL) {
 327			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 328			xferlevel |= bytes_per_word - 1;
 329		}
 330
 331		mcspi_write_reg(ctlr, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 332		mcspi_write_chconf0(spi, chconf);
 333		mcspi->fifo_depth = max_fifo_depth;
 334
 335		return;
 336	}
 337
 338disable_fifo:
 339	if (t->rx_buf != NULL)
 340		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 341
 342	if (t->tx_buf != NULL)
 343		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 344
 345	mcspi_write_chconf0(spi, chconf);
 346	mcspi->fifo_depth = 0;
 347}
 348
 349static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 350{
 351	unsigned long timeout;
 352
 353	timeout = jiffies + msecs_to_jiffies(1000);
 354	while (!(readl_relaxed(reg) & bit)) {
 355		if (time_after(jiffies, timeout)) {
 356			if (!(readl_relaxed(reg) & bit))
 357				return -ETIMEDOUT;
 358			else
 359				return 0;
 360		}
 361		cpu_relax();
 362	}
 363	return 0;
 364}
 365
 366static int mcspi_wait_for_completion(struct  omap2_mcspi *mcspi,
 367				     struct completion *x)
 368{
 369	if (spi_controller_is_target(mcspi->ctlr)) {
 370		if (wait_for_completion_interruptible(x) ||
 371		    mcspi->target_aborted)
 372			return -EINTR;
 373	} else {
 374		wait_for_completion(x);
 375	}
 376
 377	return 0;
 378}
 379
 380static void omap2_mcspi_rx_callback(void *data)
 381{
 382	struct spi_device *spi = data;
 383	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
 384	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 385
 386	/* We must disable the DMA RX request */
 387	omap2_mcspi_set_dma_req(spi, 1, 0);
 388
 389	complete(&mcspi_dma->dma_rx_completion);
 390}
 391
 392static void omap2_mcspi_tx_callback(void *data)
 393{
 394	struct spi_device *spi = data;
 395	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
 396	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 397
 398	/* We must disable the DMA TX request */
 399	omap2_mcspi_set_dma_req(spi, 0, 0);
 400
 401	complete(&mcspi_dma->dma_tx_completion);
 402}
 403
 404static void omap2_mcspi_tx_dma(struct spi_device *spi,
 405				struct spi_transfer *xfer,
 406				struct dma_slave_config cfg)
 407{
 408	struct omap2_mcspi	*mcspi;
 409	struct omap2_mcspi_dma  *mcspi_dma;
 410	struct dma_async_tx_descriptor *tx;
 411
 412	mcspi = spi_controller_get_devdata(spi->controller);
 413	mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 414
 415	dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 416
 417	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 418				     xfer->tx_sg.nents,
 419				     DMA_MEM_TO_DEV,
 420				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 421	if (tx) {
 422		tx->callback = omap2_mcspi_tx_callback;
 423		tx->callback_param = spi;
 424		dmaengine_submit(tx);
 425	} else {
 426		/* FIXME: fall back to PIO? */
 427	}
 428	dma_async_issue_pending(mcspi_dma->dma_tx);
 429	omap2_mcspi_set_dma_req(spi, 0, 1);
 430}
 431
 432static unsigned
 433omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 434				struct dma_slave_config cfg,
 435				unsigned es)
 436{
 437	struct omap2_mcspi	*mcspi;
 438	struct omap2_mcspi_dma  *mcspi_dma;
 439	unsigned int		count, transfer_reduction = 0;
 440	struct scatterlist	*sg_out[2];
 441	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 442	size_t			sizes[2];
 443	u32			l;
 444	int			elements = 0;
 445	int			word_len, element_count;
 446	struct omap2_mcspi_cs	*cs = spi->controller_state;
 447	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 448	struct dma_async_tx_descriptor *tx;
 449
 450	mcspi = spi_controller_get_devdata(spi->controller);
 451	mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 452	count = xfer->len;
 453
 454	/*
 455	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 456	 *  it mentions reducing DMA transfer length by one element in host
 457	 *  normal mode.
 458	 */
 459	if (mcspi->fifo_depth == 0)
 460		transfer_reduction = es;
 461
 462	word_len = cs->word_len;
 463	l = mcspi_cached_chconf0(spi);
 464
 465	if (word_len <= 8)
 466		element_count = count;
 467	else if (word_len <= 16)
 468		element_count = count >> 1;
 469	else /* word_len <= 32 */
 470		element_count = count >> 2;
 471
 472
 473	dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 474
 475	/*
 476	 *  Reduce DMA transfer length by one more if McSPI is
 477	 *  configured in turbo mode.
 478	 */
 479	if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 480		transfer_reduction += es;
 481
 482	if (transfer_reduction) {
 483		/* Split sgl into two. The second sgl won't be used. */
 484		sizes[0] = count - transfer_reduction;
 485		sizes[1] = transfer_reduction;
 486		nb_sizes = 2;
 487	} else {
 488		/*
 489		 * Don't bother splitting the sgl. This essentially
 490		 * clones the original sgl.
 491		 */
 492		sizes[0] = count;
 493		nb_sizes = 1;
 494	}
 495
 496	ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
 497		       sizes, sg_out, out_mapped_nents, GFP_KERNEL);
 498
 499	if (ret < 0) {
 500		dev_err(&spi->dev, "sg_split failed\n");
 501		return 0;
 502	}
 503
 504	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
 505				     out_mapped_nents[0], DMA_DEV_TO_MEM,
 506				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 507	if (tx) {
 508		tx->callback = omap2_mcspi_rx_callback;
 509		tx->callback_param = spi;
 510		dmaengine_submit(tx);
 511	} else {
 512		/* FIXME: fall back to PIO? */
 513	}
 514
 515	dma_async_issue_pending(mcspi_dma->dma_rx);
 516	omap2_mcspi_set_dma_req(spi, 1, 1);
 517
 518	ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
 519	if (ret || mcspi->target_aborted) {
 520		dmaengine_terminate_sync(mcspi_dma->dma_rx);
 521		omap2_mcspi_set_dma_req(spi, 1, 0);
 522		return 0;
 523	}
 524
 525	for (x = 0; x < nb_sizes; x++)
 526		kfree(sg_out[x]);
 527
 528	if (mcspi->fifo_depth > 0)
 529		return count;
 530
 531	/*
 532	 *  Due to the DMA transfer length reduction the missing bytes must
 533	 *  be read manually to receive all of the expected data.
 534	 */
 535	omap2_mcspi_set_enable(spi, 0);
 536
 537	elements = element_count - 1;
 538
 539	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 540		elements--;
 541
 542		if (!mcspi_wait_for_reg_bit(chstat_reg,
 543					    OMAP2_MCSPI_CHSTAT_RXS)) {
 544			u32 w;
 545
 546			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 547			if (word_len <= 8)
 548				((u8 *)xfer->rx_buf)[elements++] = w;
 549			else if (word_len <= 16)
 550				((u16 *)xfer->rx_buf)[elements++] = w;
 551			else /* word_len <= 32 */
 552				((u32 *)xfer->rx_buf)[elements++] = w;
 553		} else {
 554			int bytes_per_word = mcspi_bytes_per_word(word_len);
 555			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 556			count -= (bytes_per_word << 1);
 557			omap2_mcspi_set_enable(spi, 1);
 558			return count;
 559		}
 560	}
 561	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 562		u32 w;
 563
 564		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 565		if (word_len <= 8)
 566			((u8 *)xfer->rx_buf)[elements] = w;
 567		else if (word_len <= 16)
 568			((u16 *)xfer->rx_buf)[elements] = w;
 569		else /* word_len <= 32 */
 570			((u32 *)xfer->rx_buf)[elements] = w;
 571	} else {
 572		dev_err(&spi->dev, "DMA RX last word empty\n");
 573		count -= mcspi_bytes_per_word(word_len);
 574	}
 575	omap2_mcspi_set_enable(spi, 1);
 576	return count;
 577}
 578
 579static unsigned
 580omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 581{
 582	struct omap2_mcspi	*mcspi;
 583	struct omap2_mcspi_cs	*cs = spi->controller_state;
 584	struct omap2_mcspi_dma  *mcspi_dma;
 585	unsigned int		count;
 586	u8			*rx;
 587	const u8		*tx;
 588	struct dma_slave_config	cfg;
 589	enum dma_slave_buswidth width;
 590	unsigned es;
 591	void __iomem		*chstat_reg;
 592	void __iomem            *irqstat_reg;
 593	int			wait_res;
 594
 595	mcspi = spi_controller_get_devdata(spi->controller);
 596	mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 597
 598	if (cs->word_len <= 8) {
 599		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 600		es = 1;
 601	} else if (cs->word_len <= 16) {
 602		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 603		es = 2;
 604	} else {
 605		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 606		es = 4;
 607	}
 608
 609	count = xfer->len;
 610
 611	memset(&cfg, 0, sizeof(cfg));
 612	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 613	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 614	cfg.src_addr_width = width;
 615	cfg.dst_addr_width = width;
 616	cfg.src_maxburst = 1;
 617	cfg.dst_maxburst = 1;
 618
 619	rx = xfer->rx_buf;
 620	tx = xfer->tx_buf;
 621
 622	mcspi->target_aborted = false;
 623	reinit_completion(&mcspi_dma->dma_tx_completion);
 624	reinit_completion(&mcspi_dma->dma_rx_completion);
 625	reinit_completion(&mcspi->txdone);
 626	if (tx) {
 627		/* Enable EOW IRQ to know end of tx in target mode */
 628		if (spi_controller_is_target(spi->controller))
 629			mcspi_write_reg(spi->controller,
 630					OMAP2_MCSPI_IRQENABLE,
 631					OMAP2_MCSPI_IRQSTATUS_EOW);
 632		omap2_mcspi_tx_dma(spi, xfer, cfg);
 633	}
 634
 635	if (rx != NULL)
 636		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 637
 638	if (tx != NULL) {
 639		int ret;
 640
 641		ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
 642		if (ret || mcspi->target_aborted) {
 643			dmaengine_terminate_sync(mcspi_dma->dma_tx);
 644			omap2_mcspi_set_dma_req(spi, 0, 0);
 645			return 0;
 646		}
 647
 648		if (spi_controller_is_target(mcspi->ctlr)) {
 649			ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
 650			if (ret || mcspi->target_aborted)
 651				return 0;
 652		}
 653
 654		if (mcspi->fifo_depth > 0) {
 655			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 656
 657			if (mcspi_wait_for_reg_bit(irqstat_reg,
 658						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 659				dev_err(&spi->dev, "EOW timed out\n");
 660
 661			mcspi_write_reg(mcspi->ctlr, OMAP2_MCSPI_IRQSTATUS,
 662					OMAP2_MCSPI_IRQSTATUS_EOW);
 663		}
 664
 665		/* for TX_ONLY mode, be sure all words have shifted out */
 666		if (rx == NULL) {
 667			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 668			if (mcspi->fifo_depth > 0) {
 669				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 670						OMAP2_MCSPI_CHSTAT_TXFFE);
 671				if (wait_res < 0)
 672					dev_err(&spi->dev, "TXFFE timed out\n");
 673			} else {
 674				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 675						OMAP2_MCSPI_CHSTAT_TXS);
 676				if (wait_res < 0)
 677					dev_err(&spi->dev, "TXS timed out\n");
 678			}
 679			if (wait_res >= 0 &&
 680				(mcspi_wait_for_reg_bit(chstat_reg,
 681					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 682				dev_err(&spi->dev, "EOT timed out\n");
 683		}
 684	}
 685	return count;
 686}
 687
 688static unsigned
 689omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 690{
 691	struct omap2_mcspi_cs	*cs = spi->controller_state;
 692	unsigned int		count, c;
 693	u32			l;
 694	void __iomem		*base = cs->base;
 695	void __iomem		*tx_reg;
 696	void __iomem		*rx_reg;
 697	void __iomem		*chstat_reg;
 698	int			word_len;
 699
 700	count = xfer->len;
 701	c = count;
 702	word_len = cs->word_len;
 703
 704	l = mcspi_cached_chconf0(spi);
 705
 706	/* We store the pre-calculated register addresses on stack to speed
 707	 * up the transfer loop. */
 708	tx_reg		= base + OMAP2_MCSPI_TX0;
 709	rx_reg		= base + OMAP2_MCSPI_RX0;
 710	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 711
 712	if (c < (word_len>>3))
 713		return 0;
 714
 715	if (word_len <= 8) {
 716		u8		*rx;
 717		const u8	*tx;
 718
 719		rx = xfer->rx_buf;
 720		tx = xfer->tx_buf;
 721
 722		do {
 723			c -= 1;
 724			if (tx != NULL) {
 725				if (mcspi_wait_for_reg_bit(chstat_reg,
 726						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 727					dev_err(&spi->dev, "TXS timed out\n");
 728					goto out;
 729				}
 730				dev_vdbg(&spi->dev, "write-%d %02x\n",
 731						word_len, *tx);
 732				writel_relaxed(*tx++, tx_reg);
 733			}
 734			if (rx != NULL) {
 735				if (mcspi_wait_for_reg_bit(chstat_reg,
 736						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 737					dev_err(&spi->dev, "RXS timed out\n");
 738					goto out;
 739				}
 740
 741				if (c == 1 && tx == NULL &&
 742				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 743					omap2_mcspi_set_enable(spi, 0);
 744					*rx++ = readl_relaxed(rx_reg);
 745					dev_vdbg(&spi->dev, "read-%d %02x\n",
 746						    word_len, *(rx - 1));
 747					if (mcspi_wait_for_reg_bit(chstat_reg,
 748						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 749						dev_err(&spi->dev,
 750							"RXS timed out\n");
 751						goto out;
 752					}
 753					c = 0;
 754				} else if (c == 0 && tx == NULL) {
 755					omap2_mcspi_set_enable(spi, 0);
 756				}
 757
 758				*rx++ = readl_relaxed(rx_reg);
 759				dev_vdbg(&spi->dev, "read-%d %02x\n",
 760						word_len, *(rx - 1));
 761			}
 762			/* Add word delay between each word */
 763			spi_delay_exec(&xfer->word_delay, xfer);
 764		} while (c);
 765	} else if (word_len <= 16) {
 766		u16		*rx;
 767		const u16	*tx;
 768
 769		rx = xfer->rx_buf;
 770		tx = xfer->tx_buf;
 771		do {
 772			c -= 2;
 773			if (tx != NULL) {
 774				if (mcspi_wait_for_reg_bit(chstat_reg,
 775						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 776					dev_err(&spi->dev, "TXS timed out\n");
 777					goto out;
 778				}
 779				dev_vdbg(&spi->dev, "write-%d %04x\n",
 780						word_len, *tx);
 781				writel_relaxed(*tx++, tx_reg);
 782			}
 783			if (rx != NULL) {
 784				if (mcspi_wait_for_reg_bit(chstat_reg,
 785						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 786					dev_err(&spi->dev, "RXS timed out\n");
 787					goto out;
 788				}
 789
 790				if (c == 2 && tx == NULL &&
 791				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 792					omap2_mcspi_set_enable(spi, 0);
 793					*rx++ = readl_relaxed(rx_reg);
 794					dev_vdbg(&spi->dev, "read-%d %04x\n",
 795						    word_len, *(rx - 1));
 796					if (mcspi_wait_for_reg_bit(chstat_reg,
 797						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 798						dev_err(&spi->dev,
 799							"RXS timed out\n");
 800						goto out;
 801					}
 802					c = 0;
 803				} else if (c == 0 && tx == NULL) {
 804					omap2_mcspi_set_enable(spi, 0);
 805				}
 806
 807				*rx++ = readl_relaxed(rx_reg);
 808				dev_vdbg(&spi->dev, "read-%d %04x\n",
 809						word_len, *(rx - 1));
 810			}
 811			/* Add word delay between each word */
 812			spi_delay_exec(&xfer->word_delay, xfer);
 813		} while (c >= 2);
 814	} else if (word_len <= 32) {
 815		u32		*rx;
 816		const u32	*tx;
 817
 818		rx = xfer->rx_buf;
 819		tx = xfer->tx_buf;
 820		do {
 821			c -= 4;
 822			if (tx != NULL) {
 823				if (mcspi_wait_for_reg_bit(chstat_reg,
 824						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 825					dev_err(&spi->dev, "TXS timed out\n");
 826					goto out;
 827				}
 828				dev_vdbg(&spi->dev, "write-%d %08x\n",
 829						word_len, *tx);
 830				writel_relaxed(*tx++, tx_reg);
 831			}
 832			if (rx != NULL) {
 833				if (mcspi_wait_for_reg_bit(chstat_reg,
 834						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 835					dev_err(&spi->dev, "RXS timed out\n");
 836					goto out;
 837				}
 838
 839				if (c == 4 && tx == NULL &&
 840				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 841					omap2_mcspi_set_enable(spi, 0);
 842					*rx++ = readl_relaxed(rx_reg);
 843					dev_vdbg(&spi->dev, "read-%d %08x\n",
 844						    word_len, *(rx - 1));
 845					if (mcspi_wait_for_reg_bit(chstat_reg,
 846						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 847						dev_err(&spi->dev,
 848							"RXS timed out\n");
 849						goto out;
 850					}
 851					c = 0;
 852				} else if (c == 0 && tx == NULL) {
 853					omap2_mcspi_set_enable(spi, 0);
 854				}
 855
 856				*rx++ = readl_relaxed(rx_reg);
 857				dev_vdbg(&spi->dev, "read-%d %08x\n",
 858						word_len, *(rx - 1));
 859			}
 860			/* Add word delay between each word */
 861			spi_delay_exec(&xfer->word_delay, xfer);
 862		} while (c >= 4);
 863	}
 864
 865	/* for TX_ONLY mode, be sure all words have shifted out */
 866	if (xfer->rx_buf == NULL) {
 867		if (mcspi_wait_for_reg_bit(chstat_reg,
 868				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 869			dev_err(&spi->dev, "TXS timed out\n");
 870		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 871				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 872			dev_err(&spi->dev, "EOT timed out\n");
 873
 874		/* disable chan to purge rx datas received in TX_ONLY transfer,
 875		 * otherwise these rx datas will affect the direct following
 876		 * RX_ONLY transfer.
 877		 */
 878		omap2_mcspi_set_enable(spi, 0);
 879	}
 880out:
 881	omap2_mcspi_set_enable(spi, 1);
 882	return count - c;
 883}
 884
 885static u32 omap2_mcspi_calc_divisor(u32 speed_hz, u32 ref_clk_hz)
 886{
 887	u32 div;
 888
 889	for (div = 0; div < 15; div++)
 890		if (speed_hz >= (ref_clk_hz >> div))
 891			return div;
 892
 893	return 15;
 894}
 895
 896/* called only when no transfer is active to this device */
 897static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 898		struct spi_transfer *t)
 899{
 900	struct omap2_mcspi_cs *cs = spi->controller_state;
 901	struct omap2_mcspi *mcspi;
 902	u32 ref_clk_hz, l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 903	u8 word_len = spi->bits_per_word;
 904	u32 speed_hz = spi->max_speed_hz;
 905
 906	mcspi = spi_controller_get_devdata(spi->controller);
 907
 908	if (t != NULL && t->bits_per_word)
 909		word_len = t->bits_per_word;
 910
 911	cs->word_len = word_len;
 912
 913	if (t && t->speed_hz)
 914		speed_hz = t->speed_hz;
 915
 916	ref_clk_hz = mcspi->ref_clk_hz;
 917	speed_hz = min_t(u32, speed_hz, ref_clk_hz);
 918	if (speed_hz < (ref_clk_hz / OMAP2_MCSPI_MAX_DIVIDER)) {
 919		clkd = omap2_mcspi_calc_divisor(speed_hz, ref_clk_hz);
 920		speed_hz = ref_clk_hz >> clkd;
 921		clkg = 0;
 922	} else {
 923		div = (ref_clk_hz + speed_hz - 1) / speed_hz;
 924		speed_hz = ref_clk_hz / div;
 925		clkd = (div - 1) & 0xf;
 926		extclk = (div - 1) >> 4;
 927		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 928	}
 929
 930	l = mcspi_cached_chconf0(spi);
 931
 932	/* standard 4-wire host mode:  SCK, MOSI/out, MISO/in, nCS
 933	 * REVISIT: this controller could support SPI_3WIRE mode.
 934	 */
 935	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 936		l &= ~OMAP2_MCSPI_CHCONF_IS;
 937		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 938		l |= OMAP2_MCSPI_CHCONF_DPE0;
 939	} else {
 940		l |= OMAP2_MCSPI_CHCONF_IS;
 941		l |= OMAP2_MCSPI_CHCONF_DPE1;
 942		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 943	}
 944
 945	/* wordlength */
 946	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 947	l |= (word_len - 1) << 7;
 948
 949	/* set chipselect polarity; manage with FORCE */
 950	if (!(spi->mode & SPI_CS_HIGH))
 951		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 952	else
 953		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 954
 955	/* set clock divisor */
 956	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 957	l |= clkd << 2;
 958
 959	/* set clock granularity */
 960	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 961	l |= clkg;
 962	if (clkg) {
 963		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 964		cs->chctrl0 |= extclk << 8;
 965		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 966	}
 967
 968	/* set SPI mode 0..3 */
 969	if (spi->mode & SPI_CPOL)
 970		l |= OMAP2_MCSPI_CHCONF_POL;
 971	else
 972		l &= ~OMAP2_MCSPI_CHCONF_POL;
 973	if (spi->mode & SPI_CPHA)
 974		l |= OMAP2_MCSPI_CHCONF_PHA;
 975	else
 976		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 977
 978	mcspi_write_chconf0(spi, l);
 979
 980	cs->mode = spi->mode;
 981
 982	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 983			speed_hz,
 984			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 985			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 986
 987	return 0;
 988}
 989
 990/*
 991 * Note that we currently allow DMA only if we get a channel
 992 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 993 */
 994static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
 995				   struct omap2_mcspi_dma *mcspi_dma)
 996{
 997	int ret = 0;
 998
 999	mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
1000					     mcspi_dma->dma_rx_ch_name);
1001	if (IS_ERR(mcspi_dma->dma_rx)) {
1002		ret = PTR_ERR(mcspi_dma->dma_rx);
1003		mcspi_dma->dma_rx = NULL;
1004		goto no_dma;
1005	}
1006
1007	mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
1008					     mcspi_dma->dma_tx_ch_name);
1009	if (IS_ERR(mcspi_dma->dma_tx)) {
1010		ret = PTR_ERR(mcspi_dma->dma_tx);
1011		mcspi_dma->dma_tx = NULL;
1012		dma_release_channel(mcspi_dma->dma_rx);
1013		mcspi_dma->dma_rx = NULL;
1014	}
1015
1016	init_completion(&mcspi_dma->dma_rx_completion);
1017	init_completion(&mcspi_dma->dma_tx_completion);
1018
1019no_dma:
1020	return ret;
1021}
1022
1023static void omap2_mcspi_release_dma(struct spi_controller *ctlr)
1024{
1025	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1026	struct omap2_mcspi_dma	*mcspi_dma;
1027	int i;
1028
1029	for (i = 0; i < ctlr->num_chipselect; i++) {
1030		mcspi_dma = &mcspi->dma_channels[i];
1031
1032		if (mcspi_dma->dma_rx) {
1033			dma_release_channel(mcspi_dma->dma_rx);
1034			mcspi_dma->dma_rx = NULL;
1035		}
1036		if (mcspi_dma->dma_tx) {
1037			dma_release_channel(mcspi_dma->dma_tx);
1038			mcspi_dma->dma_tx = NULL;
1039		}
1040	}
1041}
1042
1043static void omap2_mcspi_cleanup(struct spi_device *spi)
1044{
1045	struct omap2_mcspi_cs	*cs;
1046
1047	if (spi->controller_state) {
1048		/* Unlink controller state from context save list */
1049		cs = spi->controller_state;
1050		list_del(&cs->node);
1051
1052		kfree(cs);
1053	}
1054}
1055
1056static int omap2_mcspi_setup(struct spi_device *spi)
1057{
1058	bool			initial_setup = false;
1059	int			ret;
1060	struct omap2_mcspi	*mcspi = spi_controller_get_devdata(spi->controller);
1061	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1062	struct omap2_mcspi_cs	*cs = spi->controller_state;
1063
1064	if (!cs) {
1065		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1066		if (!cs)
1067			return -ENOMEM;
1068		cs->base = mcspi->base + spi_get_chipselect(spi, 0) * 0x14;
1069		cs->phys = mcspi->phys + spi_get_chipselect(spi, 0) * 0x14;
1070		cs->mode = 0;
1071		cs->chconf0 = 0;
1072		cs->chctrl0 = 0;
1073		spi->controller_state = cs;
1074		/* Link this to context save list */
1075		list_add_tail(&cs->node, &ctx->cs);
1076		initial_setup = true;
1077	}
1078
1079	ret = pm_runtime_resume_and_get(mcspi->dev);
1080	if (ret < 0) {
1081		if (initial_setup)
1082			omap2_mcspi_cleanup(spi);
1083
1084		return ret;
1085	}
1086
1087	ret = omap2_mcspi_setup_transfer(spi, NULL);
1088	if (ret && initial_setup)
1089		omap2_mcspi_cleanup(spi);
1090
1091	pm_runtime_mark_last_busy(mcspi->dev);
1092	pm_runtime_put_autosuspend(mcspi->dev);
1093
1094	return ret;
1095}
1096
1097static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1098{
1099	struct omap2_mcspi *mcspi = data;
1100	u32 irqstat;
1101
1102	irqstat	= mcspi_read_reg(mcspi->ctlr, OMAP2_MCSPI_IRQSTATUS);
1103	if (!irqstat)
1104		return IRQ_NONE;
1105
1106	/* Disable IRQ and wakeup target xfer task */
1107	mcspi_write_reg(mcspi->ctlr, OMAP2_MCSPI_IRQENABLE, 0);
1108	if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1109		complete(&mcspi->txdone);
1110
1111	return IRQ_HANDLED;
1112}
1113
1114static int omap2_mcspi_target_abort(struct spi_controller *ctlr)
1115{
1116	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1117	struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1118
1119	mcspi->target_aborted = true;
1120	complete(&mcspi_dma->dma_rx_completion);
1121	complete(&mcspi_dma->dma_tx_completion);
1122	complete(&mcspi->txdone);
1123
1124	return 0;
1125}
1126
1127static int omap2_mcspi_transfer_one(struct spi_controller *ctlr,
1128				    struct spi_device *spi,
1129				    struct spi_transfer *t)
1130{
1131
1132	/* We only enable one channel at a time -- the one whose message is
1133	 * -- although this controller would gladly
1134	 * arbitrate among multiple channels.  This corresponds to "single
1135	 * channel" host mode.  As a side effect, we need to manage the
1136	 * chipselect with the FORCE bit ... CS != channel enable.
1137	 */
1138
1139	struct omap2_mcspi		*mcspi;
1140	struct omap2_mcspi_dma		*mcspi_dma;
1141	struct omap2_mcspi_cs		*cs;
1142	struct omap2_mcspi_device_config *cd;
1143	int				par_override = 0;
1144	int				status = 0;
1145	u32				chconf;
1146
1147	mcspi = spi_controller_get_devdata(ctlr);
1148	mcspi_dma = mcspi->dma_channels + spi_get_chipselect(spi, 0);
1149	cs = spi->controller_state;
1150	cd = spi->controller_data;
1151
1152	/*
1153	 * The target driver could have changed spi->mode in which case
1154	 * it will be different from cs->mode (the current hardware setup).
1155	 * If so, set par_override (even though its not a parity issue) so
1156	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1157	 * with the correct mode on the first iteration of the loop below.
1158	 */
1159	if (spi->mode != cs->mode)
1160		par_override = 1;
1161
1162	omap2_mcspi_set_enable(spi, 0);
1163
1164	if (spi_get_csgpiod(spi, 0))
1165		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1166
1167	if (par_override ||
1168	    (t->speed_hz != spi->max_speed_hz) ||
1169	    (t->bits_per_word != spi->bits_per_word)) {
1170		par_override = 1;
1171		status = omap2_mcspi_setup_transfer(spi, t);
1172		if (status < 0)
1173			goto out;
1174		if (t->speed_hz == spi->max_speed_hz &&
1175		    t->bits_per_word == spi->bits_per_word)
1176			par_override = 0;
1177	}
1178	if (cd && cd->cs_per_word) {
1179		chconf = mcspi->ctx.modulctrl;
1180		chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1181		mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, chconf);
1182		mcspi->ctx.modulctrl =
1183			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1184	}
1185
1186	chconf = mcspi_cached_chconf0(spi);
1187	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1188	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1189
1190	if (t->tx_buf == NULL)
1191		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1192	else if (t->rx_buf == NULL)
1193		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1194
1195	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1196		/* Turbo mode is for more than one word */
1197		if (t->len > ((cs->word_len + 7) >> 3))
1198			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1199	}
1200
1201	mcspi_write_chconf0(spi, chconf);
1202
1203	if (t->len) {
1204		unsigned	count;
1205
1206		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1207		    ctlr->cur_msg_mapped &&
1208		    ctlr->can_dma(ctlr, spi, t))
1209			omap2_mcspi_set_fifo(spi, t, 1);
1210
1211		omap2_mcspi_set_enable(spi, 1);
1212
1213		/* RX_ONLY mode needs dummy data in TX reg */
1214		if (t->tx_buf == NULL)
1215			writel_relaxed(0, cs->base
1216					+ OMAP2_MCSPI_TX0);
1217
1218		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1219		    ctlr->cur_msg_mapped &&
1220		    ctlr->can_dma(ctlr, spi, t))
1221			count = omap2_mcspi_txrx_dma(spi, t);
1222		else
1223			count = omap2_mcspi_txrx_pio(spi, t);
1224
1225		if (count != t->len) {
1226			status = -EIO;
1227			goto out;
1228		}
1229	}
1230
1231	omap2_mcspi_set_enable(spi, 0);
1232
1233	if (mcspi->fifo_depth > 0)
1234		omap2_mcspi_set_fifo(spi, t, 0);
1235
1236out:
1237	/* Restore defaults if they were overriden */
1238	if (par_override) {
1239		par_override = 0;
1240		status = omap2_mcspi_setup_transfer(spi, NULL);
1241	}
1242
1243	if (cd && cd->cs_per_word) {
1244		chconf = mcspi->ctx.modulctrl;
1245		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1246		mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, chconf);
1247		mcspi->ctx.modulctrl =
1248			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1249	}
1250
1251	omap2_mcspi_set_enable(spi, 0);
1252
1253	if (spi_get_csgpiod(spi, 0))
1254		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1255
1256	if (mcspi->fifo_depth > 0 && t)
1257		omap2_mcspi_set_fifo(spi, t, 0);
1258
1259	return status;
1260}
1261
1262static int omap2_mcspi_prepare_message(struct spi_controller *ctlr,
1263				       struct spi_message *msg)
1264{
1265	struct omap2_mcspi	*mcspi = spi_controller_get_devdata(ctlr);
1266	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1267	struct omap2_mcspi_cs	*cs;
1268
1269	/* Only a single channel can have the FORCE bit enabled
1270	 * in its chconf0 register.
1271	 * Scan all channels and disable them except the current one.
1272	 * A FORCE can remain from a last transfer having cs_change enabled
1273	 */
1274	list_for_each_entry(cs, &ctx->cs, node) {
1275		if (msg->spi->controller_state == cs)
1276			continue;
1277
1278		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1279			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1280			writel_relaxed(cs->chconf0,
1281					cs->base + OMAP2_MCSPI_CHCONF0);
1282			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1283		}
1284	}
1285
1286	return 0;
1287}
1288
1289static bool omap2_mcspi_can_dma(struct spi_controller *ctlr,
1290				struct spi_device *spi,
1291				struct spi_transfer *xfer)
1292{
1293	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
1294	struct omap2_mcspi_dma *mcspi_dma =
1295		&mcspi->dma_channels[spi_get_chipselect(spi, 0)];
1296
1297	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1298		return false;
1299
1300	if (spi_controller_is_target(ctlr))
1301		return true;
1302
1303	ctlr->dma_rx = mcspi_dma->dma_rx;
1304	ctlr->dma_tx = mcspi_dma->dma_tx;
1305
1306	return (xfer->len >= DMA_MIN_BYTES);
1307}
1308
1309static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1310{
1311	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
1312	struct omap2_mcspi_dma *mcspi_dma =
1313		&mcspi->dma_channels[spi_get_chipselect(spi, 0)];
1314
1315	if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1316		return mcspi->max_xfer_len;
1317
1318	return SIZE_MAX;
1319}
1320
1321static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1322{
1323	struct spi_controller	*ctlr = mcspi->ctlr;
1324	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1325	int			ret = 0;
1326
1327	ret = pm_runtime_resume_and_get(mcspi->dev);
1328	if (ret < 0)
1329		return ret;
1330
1331	mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE,
1332			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1333	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1334
1335	omap2_mcspi_set_mode(ctlr);
1336	pm_runtime_mark_last_busy(mcspi->dev);
1337	pm_runtime_put_autosuspend(mcspi->dev);
1338	return 0;
1339}
1340
1341static int omap_mcspi_runtime_suspend(struct device *dev)
1342{
1343	int error;
1344
1345	error = pinctrl_pm_select_idle_state(dev);
1346	if (error)
1347		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1348
1349	return 0;
1350}
1351
1352/*
1353 * When SPI wake up from off-mode, CS is in activate state. If it was in
1354 * inactive state when driver was suspend, then force it to inactive state at
1355 * wake up.
1356 */
1357static int omap_mcspi_runtime_resume(struct device *dev)
1358{
1359	struct spi_controller *ctlr = dev_get_drvdata(dev);
1360	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1361	struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1362	struct omap2_mcspi_cs *cs;
1363	int error;
1364
1365	error = pinctrl_pm_select_default_state(dev);
1366	if (error)
1367		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1368
1369	/* McSPI: context restore */
1370	mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1371	mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1372
1373	list_for_each_entry(cs, &ctx->cs, node) {
1374		/*
1375		 * We need to toggle CS state for OMAP take this
1376		 * change in account.
1377		 */
1378		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1379			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1380			writel_relaxed(cs->chconf0,
1381				       cs->base + OMAP2_MCSPI_CHCONF0);
1382			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1383			writel_relaxed(cs->chconf0,
1384				       cs->base + OMAP2_MCSPI_CHCONF0);
1385		} else {
1386			writel_relaxed(cs->chconf0,
1387				       cs->base + OMAP2_MCSPI_CHCONF0);
1388		}
1389	}
1390
1391	return 0;
1392}
1393
1394static struct omap2_mcspi_platform_config omap2_pdata = {
1395	.regs_offset = 0,
1396};
1397
1398static struct omap2_mcspi_platform_config omap4_pdata = {
1399	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1400};
1401
1402static struct omap2_mcspi_platform_config am654_pdata = {
1403	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1404	.max_xfer_len = SZ_4K - 1,
1405};
1406
1407static const struct of_device_id omap_mcspi_of_match[] = {
1408	{
1409		.compatible = "ti,omap2-mcspi",
1410		.data = &omap2_pdata,
1411	},
1412	{
1413		.compatible = "ti,omap4-mcspi",
1414		.data = &omap4_pdata,
1415	},
1416	{
1417		.compatible = "ti,am654-mcspi",
1418		.data = &am654_pdata,
1419	},
1420	{ },
1421};
1422MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1423
1424static int omap2_mcspi_probe(struct platform_device *pdev)
1425{
1426	struct spi_controller	*ctlr;
1427	const struct omap2_mcspi_platform_config *pdata;
1428	struct omap2_mcspi	*mcspi;
1429	struct resource		*r;
1430	int			status = 0, i;
1431	u32			regs_offset = 0;
1432	struct device_node	*node = pdev->dev.of_node;
1433	const struct of_device_id *match;
1434
1435	if (of_property_read_bool(node, "spi-slave"))
1436		ctlr = spi_alloc_target(&pdev->dev, sizeof(*mcspi));
1437	else
1438		ctlr = spi_alloc_host(&pdev->dev, sizeof(*mcspi));
1439	if (!ctlr)
1440		return -ENOMEM;
1441
1442	/* the spi->mode bits understood by this driver: */
1443	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1444	ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1445	ctlr->setup = omap2_mcspi_setup;
1446	ctlr->auto_runtime_pm = true;
1447	ctlr->prepare_message = omap2_mcspi_prepare_message;
1448	ctlr->can_dma = omap2_mcspi_can_dma;
1449	ctlr->transfer_one = omap2_mcspi_transfer_one;
1450	ctlr->set_cs = omap2_mcspi_set_cs;
1451	ctlr->cleanup = omap2_mcspi_cleanup;
1452	ctlr->target_abort = omap2_mcspi_target_abort;
1453	ctlr->dev.of_node = node;
1454	ctlr->use_gpio_descriptors = true;
 
 
1455
1456	platform_set_drvdata(pdev, ctlr);
1457
1458	mcspi = spi_controller_get_devdata(ctlr);
1459	mcspi->ctlr = ctlr;
1460
1461	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1462	if (match) {
1463		u32 num_cs = 1; /* default number of chipselect */
1464		pdata = match->data;
1465
1466		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1467		ctlr->num_chipselect = num_cs;
1468		if (of_property_read_bool(node, "ti,pindir-d0-out-d1-in"))
1469			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1470	} else {
1471		pdata = dev_get_platdata(&pdev->dev);
1472		ctlr->num_chipselect = pdata->num_cs;
1473		mcspi->pin_dir = pdata->pin_dir;
1474	}
1475	regs_offset = pdata->regs_offset;
1476	if (pdata->max_xfer_len) {
1477		mcspi->max_xfer_len = pdata->max_xfer_len;
1478		ctlr->max_transfer_size = omap2_mcspi_max_xfer_size;
1479	}
1480
1481	mcspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
 
1482	if (IS_ERR(mcspi->base)) {
1483		status = PTR_ERR(mcspi->base);
1484		goto free_ctlr;
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, ctlr->num_chipselect,
1494					   sizeof(struct omap2_mcspi_dma),
1495					   GFP_KERNEL);
1496	if (mcspi->dma_channels == NULL) {
1497		status = -ENOMEM;
1498		goto free_ctlr;
1499	}
1500
1501	for (i = 0; i < ctlr->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_ctlr;
1509	}
1510
1511	status = platform_get_irq(pdev, 0);
1512	if (status < 0)
1513		goto free_ctlr;
 
 
1514	init_completion(&mcspi->txdone);
1515	status = devm_request_irq(&pdev->dev, status,
1516				  omap2_mcspi_irq_handler, 0, pdev->name,
1517				  mcspi);
1518	if (status) {
1519		dev_err(&pdev->dev, "Cannot request IRQ");
1520		goto free_ctlr;
1521	}
1522
1523	mcspi->ref_clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
1524	if (mcspi->ref_clk)
1525		mcspi->ref_clk_hz = clk_get_rate(mcspi->ref_clk);
1526	else
1527		mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ;
1528	ctlr->max_speed_hz = mcspi->ref_clk_hz;
1529	ctlr->min_speed_hz = mcspi->ref_clk_hz >> 15;
1530
1531	pm_runtime_use_autosuspend(&pdev->dev);
1532	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1533	pm_runtime_enable(&pdev->dev);
1534
1535	status = omap2_mcspi_controller_setup(mcspi);
1536	if (status < 0)
1537		goto disable_pm;
1538
1539	status = devm_spi_register_controller(&pdev->dev, ctlr);
1540	if (status < 0)
1541		goto disable_pm;
1542
1543	return status;
1544
1545disable_pm:
1546	pm_runtime_dont_use_autosuspend(&pdev->dev);
1547	pm_runtime_put_sync(&pdev->dev);
1548	pm_runtime_disable(&pdev->dev);
1549free_ctlr:
1550	omap2_mcspi_release_dma(ctlr);
1551	spi_controller_put(ctlr);
1552	return status;
1553}
1554
1555static void omap2_mcspi_remove(struct platform_device *pdev)
1556{
1557	struct spi_controller *ctlr = platform_get_drvdata(pdev);
1558	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1559
1560	omap2_mcspi_release_dma(ctlr);
1561
1562	pm_runtime_dont_use_autosuspend(mcspi->dev);
1563	pm_runtime_put_sync(mcspi->dev);
1564	pm_runtime_disable(&pdev->dev);
 
 
1565}
1566
1567/* work with hotplug and coldplug */
1568MODULE_ALIAS("platform:omap2_mcspi");
1569
1570static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1571{
1572	struct spi_controller *ctlr = dev_get_drvdata(dev);
1573	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1574	int error;
1575
1576	error = pinctrl_pm_select_sleep_state(dev);
1577	if (error)
1578		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1579			 __func__, error);
1580
1581	error = spi_controller_suspend(ctlr);
1582	if (error)
1583		dev_warn(mcspi->dev, "%s: controller suspend failed: %i\n",
1584			 __func__, error);
1585
1586	return pm_runtime_force_suspend(dev);
1587}
1588
1589static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1590{
1591	struct spi_controller *ctlr = dev_get_drvdata(dev);
1592	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1593	int error;
1594
1595	error = spi_controller_resume(ctlr);
1596	if (error)
1597		dev_warn(mcspi->dev, "%s: controller resume failed: %i\n",
1598			 __func__, error);
1599
1600	return pm_runtime_force_resume(dev);
1601}
1602
1603static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1604	SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1605				omap2_mcspi_resume)
1606	.runtime_suspend	= omap_mcspi_runtime_suspend,
1607	.runtime_resume		= omap_mcspi_runtime_resume,
1608};
1609
1610static struct platform_driver omap2_mcspi_driver = {
1611	.driver = {
1612		.name =		"omap2_mcspi",
1613		.pm =		&omap2_mcspi_pm_ops,
1614		.of_match_table = omap_mcspi_of_match,
1615	},
1616	.probe =	omap2_mcspi_probe,
1617	.remove_new =	omap2_mcspi_remove,
1618};
1619
1620module_platform_driver(omap2_mcspi_driver);
1621MODULE_LICENSE("GPL");
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");