Linux Audio

Check our new training course

Loading...
v6.13.7
   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 "internals.h"
  31
  32#include <linux/platform_data/spi-omap2-mcspi.h>
  33
  34#define OMAP2_MCSPI_MAX_FREQ		48000000
  35#define OMAP2_MCSPI_MAX_DIVIDER		4096
  36#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  37#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  38#define SPI_AUTOSUSPEND_TIMEOUT		2000
  39
  40#define OMAP2_MCSPI_REVISION		0x00
  41#define OMAP2_MCSPI_SYSSTATUS		0x14
  42#define OMAP2_MCSPI_IRQSTATUS		0x18
  43#define OMAP2_MCSPI_IRQENABLE		0x1c
  44#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  45#define OMAP2_MCSPI_SYST		0x24
  46#define OMAP2_MCSPI_MODULCTRL		0x28
  47#define OMAP2_MCSPI_XFERLEVEL		0x7c
  48
  49/* per-channel banks, 0x14 bytes each, first is: */
  50#define OMAP2_MCSPI_CHCONF0		0x2c
  51#define OMAP2_MCSPI_CHSTAT0		0x30
  52#define OMAP2_MCSPI_CHCTRL0		0x34
  53#define OMAP2_MCSPI_TX0			0x38
  54#define OMAP2_MCSPI_RX0			0x3c
  55
  56/* per-register bitmasks: */
  57#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  58
  59#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  60#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  61#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  62
  63#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  64#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  65#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  66#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  67#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  68#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  69#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  70#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  71#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  72#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  73#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  74#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  75#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  76#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  77#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  78#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  79#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  80#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  81
  82#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  83#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  84#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  85#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  86
  87#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
  88#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
  89
  90#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  91
  92/* We have 2 DMA channels per CS, one for RX and one for TX */
  93struct omap2_mcspi_dma {
  94	struct dma_chan *dma_tx;
  95	struct dma_chan *dma_rx;
  96
 
 
 
  97	struct completion dma_tx_completion;
  98	struct completion dma_rx_completion;
  99
 100	char dma_rx_ch_name[14];
 101	char dma_tx_ch_name[14];
 102};
 103
 104/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 105 * cache operations; better heuristics consider wordsize and bitrate.
 106 */
 107#define DMA_MIN_BYTES			160
 108
 109
 110/*
 111 * Used for context save and restore, structure members to be updated whenever
 112 * corresponding registers are modified.
 113 */
 114struct omap2_mcspi_regs {
 115	u32 modulctrl;
 116	u32 wakeupenable;
 117	struct list_head cs;
 118};
 119
 120struct omap2_mcspi {
 121	struct completion	txdone;
 122	struct spi_controller	*ctlr;
 123	/* Virtual base address of the controller */
 124	void __iomem		*base;
 125	unsigned long		phys;
 126	/* SPI1 has 4 channels, while SPI2 has 2 */
 127	struct omap2_mcspi_dma	*dma_channels;
 128	struct device		*dev;
 129	struct omap2_mcspi_regs ctx;
 130	struct clk		*ref_clk;
 131	int			fifo_depth;
 132	bool			target_aborted;
 133	unsigned int		pin_dir:1;
 134	size_t			max_xfer_len;
 135	u32			ref_clk_hz;
 136	bool			use_multi_mode;
 137};
 138
 139struct omap2_mcspi_cs {
 140	void __iomem		*base;
 141	unsigned long		phys;
 142	int			word_len;
 143	u16			mode;
 144	struct list_head	node;
 145	/* Context save and restore shadow register */
 146	u32			chconf0, chctrl0;
 147};
 148
 149static inline void mcspi_write_reg(struct spi_controller *ctlr,
 150		int idx, u32 val)
 151{
 152	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
 153
 154	writel_relaxed(val, mcspi->base + idx);
 155}
 156
 157static inline u32 mcspi_read_reg(struct spi_controller *ctlr, int idx)
 158{
 159	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
 160
 161	return readl_relaxed(mcspi->base + idx);
 162}
 163
 164static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 165		int idx, u32 val)
 166{
 167	struct omap2_mcspi_cs	*cs = spi->controller_state;
 168
 169	writel_relaxed(val, cs->base +  idx);
 170}
 171
 172static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 173{
 174	struct omap2_mcspi_cs	*cs = spi->controller_state;
 175
 176	return readl_relaxed(cs->base + idx);
 177}
 178
 179static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 180{
 181	struct omap2_mcspi_cs *cs = spi->controller_state;
 182
 183	return cs->chconf0;
 184}
 185
 186static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 187{
 188	struct omap2_mcspi_cs *cs = spi->controller_state;
 189
 190	cs->chconf0 = val;
 191	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 192	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 193}
 194
 195static inline int mcspi_bytes_per_word(int word_len)
 196{
 197	if (word_len <= 8)
 198		return 1;
 199	else if (word_len <= 16)
 200		return 2;
 201	else /* word_len <= 32 */
 202		return 4;
 203}
 204
 205static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 206		int is_read, int enable)
 207{
 208	u32 l, rw;
 209
 210	l = mcspi_cached_chconf0(spi);
 211
 212	if (is_read) /* 1 is read, 0 write */
 213		rw = OMAP2_MCSPI_CHCONF_DMAR;
 214	else
 215		rw = OMAP2_MCSPI_CHCONF_DMAW;
 216
 217	if (enable)
 218		l |= rw;
 219	else
 220		l &= ~rw;
 221
 222	mcspi_write_chconf0(spi, l);
 223}
 224
 225static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 226{
 227	struct omap2_mcspi_cs *cs = spi->controller_state;
 228	u32 l;
 229
 230	l = cs->chctrl0;
 231	if (enable)
 232		l |= OMAP2_MCSPI_CHCTRL_EN;
 233	else
 234		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 235	cs->chctrl0 = l;
 236	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 237	/* Flash post-writes */
 238	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 239}
 240
 241static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 242{
 243	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
 244	u32 l;
 245
 246	/* The controller handles the inverted chip selects
 247	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 248	 * the inversion from the core spi_set_cs function.
 249	 */
 250	if (spi->mode & SPI_CS_HIGH)
 251		enable = !enable;
 252
 253	if (spi->controller_state) {
 254		int err = pm_runtime_resume_and_get(mcspi->dev);
 255		if (err < 0) {
 256			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 257			return;
 258		}
 259
 260		l = mcspi_cached_chconf0(spi);
 261
 262		/* Only enable chip select manually if single mode is used */
 263		if (mcspi->use_multi_mode) {
 264			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 265		} else {
 266			if (enable)
 267				l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 268			else
 269				l |= OMAP2_MCSPI_CHCONF_FORCE;
 270		}
 271
 272		mcspi_write_chconf0(spi, l);
 273
 274		pm_runtime_mark_last_busy(mcspi->dev);
 275		pm_runtime_put_autosuspend(mcspi->dev);
 276	}
 277}
 278
 279static void omap2_mcspi_set_mode(struct spi_controller *ctlr)
 280{
 281	struct omap2_mcspi	*mcspi = spi_controller_get_devdata(ctlr);
 282	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 283	u32 l;
 284
 285	/*
 286	 * Choose host or target mode
 
 287	 */
 288	l = mcspi_read_reg(ctlr, OMAP2_MCSPI_MODULCTRL);
 289	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
 290	if (spi_controller_is_target(ctlr)) {
 291		l |= (OMAP2_MCSPI_MODULCTRL_MS);
 292	} else {
 293		l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
 294
 295		/* Enable single mode if needed */
 296		if (mcspi->use_multi_mode)
 297			l &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
 298		else
 299			l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 300	}
 301	mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, l);
 302
 303	ctx->modulctrl = l;
 304}
 305
 306static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 307				struct spi_transfer *t, int enable)
 308{
 309	struct spi_controller *ctlr = spi->controller;
 310	struct omap2_mcspi_cs *cs = spi->controller_state;
 311	struct omap2_mcspi *mcspi;
 312	unsigned int wcnt;
 313	int max_fifo_depth, bytes_per_word;
 314	u32 chconf, xferlevel;
 315
 316	mcspi = spi_controller_get_devdata(ctlr);
 317
 318	chconf = mcspi_cached_chconf0(spi);
 319	if (enable) {
 320		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 321		if (t->len % bytes_per_word != 0)
 322			goto disable_fifo;
 323
 324		if (t->rx_buf != NULL && t->tx_buf != NULL)
 325			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 326		else
 327			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 328
 
 
 
 
 329		wcnt = t->len / bytes_per_word;
 330		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 331			goto disable_fifo;
 332
 333		xferlevel = wcnt << 16;
 334		if (t->rx_buf != NULL) {
 335			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 336			xferlevel |= (bytes_per_word - 1) << 8;
 337		}
 338
 339		if (t->tx_buf != NULL) {
 340			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 341			xferlevel |= bytes_per_word - 1;
 342		}
 343
 344		mcspi_write_reg(ctlr, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 345		mcspi_write_chconf0(spi, chconf);
 346		mcspi->fifo_depth = max_fifo_depth;
 347
 348		return;
 349	}
 350
 351disable_fifo:
 352	if (t->rx_buf != NULL)
 353		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 354
 355	if (t->tx_buf != NULL)
 356		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 357
 358	mcspi_write_chconf0(spi, chconf);
 359	mcspi->fifo_depth = 0;
 360}
 361
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 362static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 363{
 364	unsigned long timeout;
 365
 366	timeout = jiffies + msecs_to_jiffies(1000);
 367	while (!(readl_relaxed(reg) & bit)) {
 368		if (time_after(jiffies, timeout)) {
 369			if (!(readl_relaxed(reg) & bit))
 370				return -ETIMEDOUT;
 371			else
 372				return 0;
 373		}
 374		cpu_relax();
 375	}
 376	return 0;
 377}
 378
 379static int mcspi_wait_for_completion(struct  omap2_mcspi *mcspi,
 380				     struct completion *x)
 381{
 382	if (spi_controller_is_target(mcspi->ctlr)) {
 383		if (wait_for_completion_interruptible(x) ||
 384		    mcspi->target_aborted)
 385			return -EINTR;
 386	} else {
 387		wait_for_completion(x);
 388	}
 389
 390	return 0;
 391}
 392
 393static void omap2_mcspi_rx_callback(void *data)
 394{
 395	struct spi_device *spi = data;
 396	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
 397	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 398
 399	/* We must disable the DMA RX request */
 400	omap2_mcspi_set_dma_req(spi, 1, 0);
 401
 402	complete(&mcspi_dma->dma_rx_completion);
 403}
 404
 405static void omap2_mcspi_tx_callback(void *data)
 406{
 407	struct spi_device *spi = data;
 408	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
 409	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 410
 411	/* We must disable the DMA TX request */
 412	omap2_mcspi_set_dma_req(spi, 0, 0);
 413
 414	complete(&mcspi_dma->dma_tx_completion);
 415}
 416
 417static void omap2_mcspi_tx_dma(struct spi_device *spi,
 418				struct spi_transfer *xfer,
 419				struct dma_slave_config cfg)
 420{
 421	struct omap2_mcspi	*mcspi;
 422	struct omap2_mcspi_dma  *mcspi_dma;
 423	struct dma_async_tx_descriptor *tx;
 424
 425	mcspi = spi_controller_get_devdata(spi->controller);
 426	mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 427
 428	dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 
 
 429
 430	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 431				     xfer->tx_sg.nents,
 432				     DMA_MEM_TO_DEV,
 433				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 434	if (tx) {
 435		tx->callback = omap2_mcspi_tx_callback;
 436		tx->callback_param = spi;
 437		dmaengine_submit(tx);
 438	} else {
 439		/* FIXME: fall back to PIO? */
 
 
 
 
 
 
 
 
 
 440	}
 441	dma_async_issue_pending(mcspi_dma->dma_tx);
 442	omap2_mcspi_set_dma_req(spi, 0, 1);
 
 443}
 444
 445static unsigned
 446omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 447				struct dma_slave_config cfg,
 448				unsigned es)
 449{
 450	struct omap2_mcspi	*mcspi;
 451	struct omap2_mcspi_dma  *mcspi_dma;
 452	unsigned int		count, transfer_reduction = 0;
 453	struct scatterlist	*sg_out[2];
 454	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 455	size_t			sizes[2];
 456	u32			l;
 457	int			elements = 0;
 458	int			word_len, element_count;
 459	struct omap2_mcspi_cs	*cs = spi->controller_state;
 460	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 461	struct dma_async_tx_descriptor *tx;
 462
 463	mcspi = spi_controller_get_devdata(spi->controller);
 464	mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 465	count = xfer->len;
 
 466
 467	/*
 468	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 469	 *  it mentions reducing DMA transfer length by one element in host
 470	 *  normal mode.
 471	 */
 472	if (mcspi->fifo_depth == 0)
 473		transfer_reduction = es;
 474
 475	word_len = cs->word_len;
 476	l = mcspi_cached_chconf0(spi);
 477
 478	if (word_len <= 8)
 479		element_count = count;
 480	else if (word_len <= 16)
 481		element_count = count >> 1;
 482	else /* word_len <= 32 */
 483		element_count = count >> 2;
 484
 485
 486	dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 487
 488	/*
 489	 *  Reduce DMA transfer length by one more if McSPI is
 490	 *  configured in turbo mode.
 491	 */
 492	if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 493		transfer_reduction += es;
 494
 495	if (transfer_reduction) {
 496		/* Split sgl into two. The second sgl won't be used. */
 497		sizes[0] = count - transfer_reduction;
 498		sizes[1] = transfer_reduction;
 499		nb_sizes = 2;
 500	} else {
 501		/*
 502		 * Don't bother splitting the sgl. This essentially
 503		 * clones the original sgl.
 504		 */
 505		sizes[0] = count;
 506		nb_sizes = 1;
 507	}
 508
 509	ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
 510		       sizes, sg_out, out_mapped_nents, GFP_KERNEL);
 511
 512	if (ret < 0) {
 513		dev_err(&spi->dev, "sg_split failed\n");
 514		return 0;
 515	}
 516
 517	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
 518				     out_mapped_nents[0], DMA_DEV_TO_MEM,
 519				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 520	if (tx) {
 521		tx->callback = omap2_mcspi_rx_callback;
 522		tx->callback_param = spi;
 523		dmaengine_submit(tx);
 524	} else {
 525		/* FIXME: fall back to PIO? */
 526	}
 527
 528	dma_async_issue_pending(mcspi_dma->dma_rx);
 529	omap2_mcspi_set_dma_req(spi, 1, 1);
 530
 531	ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
 532	if (ret || mcspi->target_aborted) {
 533		dmaengine_terminate_sync(mcspi_dma->dma_rx);
 534		omap2_mcspi_set_dma_req(spi, 1, 0);
 535		return 0;
 536	}
 537
 538	for (x = 0; x < nb_sizes; x++)
 539		kfree(sg_out[x]);
 540
 541	if (mcspi->fifo_depth > 0)
 542		return count;
 543
 544	/*
 545	 *  Due to the DMA transfer length reduction the missing bytes must
 546	 *  be read manually to receive all of the expected data.
 547	 */
 548	omap2_mcspi_set_enable(spi, 0);
 549
 550	elements = element_count - 1;
 551
 552	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 553		elements--;
 554
 555		if (!mcspi_wait_for_reg_bit(chstat_reg,
 556					    OMAP2_MCSPI_CHSTAT_RXS)) {
 557			u32 w;
 558
 559			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 560			if (word_len <= 8)
 561				((u8 *)xfer->rx_buf)[elements++] = w;
 562			else if (word_len <= 16)
 563				((u16 *)xfer->rx_buf)[elements++] = w;
 564			else /* word_len <= 32 */
 565				((u32 *)xfer->rx_buf)[elements++] = w;
 566		} else {
 567			int bytes_per_word = mcspi_bytes_per_word(word_len);
 568			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 569			count -= (bytes_per_word << 1);
 570			omap2_mcspi_set_enable(spi, 1);
 571			return count;
 572		}
 573	}
 574	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 
 575		u32 w;
 576
 577		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 578		if (word_len <= 8)
 579			((u8 *)xfer->rx_buf)[elements] = w;
 580		else if (word_len <= 16)
 581			((u16 *)xfer->rx_buf)[elements] = w;
 582		else /* word_len <= 32 */
 583			((u32 *)xfer->rx_buf)[elements] = w;
 584	} else {
 585		dev_err(&spi->dev, "DMA RX last word empty\n");
 586		count -= mcspi_bytes_per_word(word_len);
 587	}
 588	omap2_mcspi_set_enable(spi, 1);
 589	return count;
 590}
 591
 592static unsigned
 593omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 594{
 595	struct omap2_mcspi	*mcspi;
 596	struct omap2_mcspi_cs	*cs = spi->controller_state;
 597	struct omap2_mcspi_dma  *mcspi_dma;
 598	unsigned int		count;
 
 599	u8			*rx;
 600	const u8		*tx;
 601	struct dma_slave_config	cfg;
 602	enum dma_slave_buswidth width;
 603	unsigned es;
 
 604	void __iomem		*chstat_reg;
 605	void __iomem            *irqstat_reg;
 606	int			wait_res;
 607
 608	mcspi = spi_controller_get_devdata(spi->controller);
 609	mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
 
 
 610
 611	if (cs->word_len <= 8) {
 612		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 613		es = 1;
 614	} else if (cs->word_len <= 16) {
 615		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 616		es = 2;
 617	} else {
 618		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 619		es = 4;
 620	}
 621
 622	count = xfer->len;
 
 
 
 
 
 
 
 
 623
 624	memset(&cfg, 0, sizeof(cfg));
 625	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 626	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 627	cfg.src_addr_width = width;
 628	cfg.dst_addr_width = width;
 629	cfg.src_maxburst = 1;
 630	cfg.dst_maxburst = 1;
 631
 632	rx = xfer->rx_buf;
 633	tx = xfer->tx_buf;
 634
 635	mcspi->target_aborted = false;
 636	reinit_completion(&mcspi_dma->dma_tx_completion);
 637	reinit_completion(&mcspi_dma->dma_rx_completion);
 638	reinit_completion(&mcspi->txdone);
 639	if (tx) {
 640		/* Enable EOW IRQ to know end of tx in target mode */
 641		if (spi_controller_is_target(spi->controller))
 642			mcspi_write_reg(spi->controller,
 643					OMAP2_MCSPI_IRQENABLE,
 644					OMAP2_MCSPI_IRQSTATUS_EOW);
 645		omap2_mcspi_tx_dma(spi, xfer, cfg);
 646	}
 647
 648	if (rx != NULL)
 649		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 650
 651	if (tx != NULL) {
 652		int ret;
 653
 654		ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
 655		if (ret || mcspi->target_aborted) {
 656			dmaengine_terminate_sync(mcspi_dma->dma_tx);
 657			omap2_mcspi_set_dma_req(spi, 0, 0);
 658			return 0;
 659		}
 660
 661		if (spi_controller_is_target(mcspi->ctlr)) {
 662			ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
 663			if (ret || mcspi->target_aborted)
 664				return 0;
 665		}
 666
 667		if (mcspi->fifo_depth > 0) {
 668			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 669
 670			if (mcspi_wait_for_reg_bit(irqstat_reg,
 671						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 672				dev_err(&spi->dev, "EOW timed out\n");
 673
 674			mcspi_write_reg(mcspi->ctlr, OMAP2_MCSPI_IRQSTATUS,
 675					OMAP2_MCSPI_IRQSTATUS_EOW);
 676		}
 677
 678		/* for TX_ONLY mode, be sure all words have shifted out */
 679		if (rx == NULL) {
 680			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 681			if (mcspi->fifo_depth > 0) {
 682				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 683						OMAP2_MCSPI_CHSTAT_TXFFE);
 684				if (wait_res < 0)
 685					dev_err(&spi->dev, "TXFFE timed out\n");
 686			} else {
 687				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 688						OMAP2_MCSPI_CHSTAT_TXS);
 689				if (wait_res < 0)
 690					dev_err(&spi->dev, "TXS timed out\n");
 691			}
 692			if (wait_res >= 0 &&
 693				(mcspi_wait_for_reg_bit(chstat_reg,
 694					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 695				dev_err(&spi->dev, "EOT timed out\n");
 696		}
 697	}
 698	return count;
 699}
 700
 701static unsigned
 702omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 703{
 
 704	struct omap2_mcspi_cs	*cs = spi->controller_state;
 705	unsigned int		count, c;
 706	u32			l;
 707	void __iomem		*base = cs->base;
 708	void __iomem		*tx_reg;
 709	void __iomem		*rx_reg;
 710	void __iomem		*chstat_reg;
 711	int			word_len;
 712
 
 713	count = xfer->len;
 714	c = count;
 715	word_len = cs->word_len;
 716
 717	l = mcspi_cached_chconf0(spi);
 718
 719	/* We store the pre-calculated register addresses on stack to speed
 720	 * up the transfer loop. */
 721	tx_reg		= base + OMAP2_MCSPI_TX0;
 722	rx_reg		= base + OMAP2_MCSPI_RX0;
 723	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 724
 725	if (c < (word_len>>3))
 726		return 0;
 727
 728	if (word_len <= 8) {
 729		u8		*rx;
 730		const u8	*tx;
 731
 732		rx = xfer->rx_buf;
 733		tx = xfer->tx_buf;
 734
 735		do {
 736			c -= 1;
 737			if (tx != NULL) {
 738				if (mcspi_wait_for_reg_bit(chstat_reg,
 739						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 740					dev_err(&spi->dev, "TXS timed out\n");
 741					goto out;
 742				}
 743				dev_vdbg(&spi->dev, "write-%d %02x\n",
 744						word_len, *tx);
 745				writel_relaxed(*tx++, tx_reg);
 746			}
 747			if (rx != NULL) {
 748				if (mcspi_wait_for_reg_bit(chstat_reg,
 749						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 750					dev_err(&spi->dev, "RXS timed out\n");
 751					goto out;
 752				}
 753
 754				if (c == 1 && tx == NULL &&
 755				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 756					omap2_mcspi_set_enable(spi, 0);
 757					*rx++ = readl_relaxed(rx_reg);
 758					dev_vdbg(&spi->dev, "read-%d %02x\n",
 759						    word_len, *(rx - 1));
 760					if (mcspi_wait_for_reg_bit(chstat_reg,
 761						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 762						dev_err(&spi->dev,
 763							"RXS timed out\n");
 764						goto out;
 765					}
 766					c = 0;
 767				} else if (c == 0 && tx == NULL) {
 768					omap2_mcspi_set_enable(spi, 0);
 769				}
 770
 771				*rx++ = readl_relaxed(rx_reg);
 772				dev_vdbg(&spi->dev, "read-%d %02x\n",
 773						word_len, *(rx - 1));
 774			}
 775			/* Add word delay between each word */
 776			spi_delay_exec(&xfer->word_delay, xfer);
 777		} while (c);
 778	} else if (word_len <= 16) {
 779		u16		*rx;
 780		const u16	*tx;
 781
 782		rx = xfer->rx_buf;
 783		tx = xfer->tx_buf;
 784		do {
 785			c -= 2;
 786			if (tx != NULL) {
 787				if (mcspi_wait_for_reg_bit(chstat_reg,
 788						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 789					dev_err(&spi->dev, "TXS timed out\n");
 790					goto out;
 791				}
 792				dev_vdbg(&spi->dev, "write-%d %04x\n",
 793						word_len, *tx);
 794				writel_relaxed(*tx++, tx_reg);
 795			}
 796			if (rx != NULL) {
 797				if (mcspi_wait_for_reg_bit(chstat_reg,
 798						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 799					dev_err(&spi->dev, "RXS timed out\n");
 800					goto out;
 801				}
 802
 803				if (c == 2 && tx == NULL &&
 804				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 805					omap2_mcspi_set_enable(spi, 0);
 806					*rx++ = readl_relaxed(rx_reg);
 807					dev_vdbg(&spi->dev, "read-%d %04x\n",
 808						    word_len, *(rx - 1));
 809					if (mcspi_wait_for_reg_bit(chstat_reg,
 810						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 811						dev_err(&spi->dev,
 812							"RXS timed out\n");
 813						goto out;
 814					}
 815					c = 0;
 816				} else if (c == 0 && tx == NULL) {
 817					omap2_mcspi_set_enable(spi, 0);
 818				}
 819
 820				*rx++ = readl_relaxed(rx_reg);
 821				dev_vdbg(&spi->dev, "read-%d %04x\n",
 822						word_len, *(rx - 1));
 823			}
 824			/* Add word delay between each word */
 825			spi_delay_exec(&xfer->word_delay, xfer);
 826		} while (c >= 2);
 827	} else if (word_len <= 32) {
 828		u32		*rx;
 829		const u32	*tx;
 830
 831		rx = xfer->rx_buf;
 832		tx = xfer->tx_buf;
 833		do {
 834			c -= 4;
 835			if (tx != NULL) {
 836				if (mcspi_wait_for_reg_bit(chstat_reg,
 837						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 838					dev_err(&spi->dev, "TXS timed out\n");
 839					goto out;
 840				}
 841				dev_vdbg(&spi->dev, "write-%d %08x\n",
 842						word_len, *tx);
 843				writel_relaxed(*tx++, tx_reg);
 844			}
 845			if (rx != NULL) {
 846				if (mcspi_wait_for_reg_bit(chstat_reg,
 847						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 848					dev_err(&spi->dev, "RXS timed out\n");
 849					goto out;
 850				}
 851
 852				if (c == 4 && tx == NULL &&
 853				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 854					omap2_mcspi_set_enable(spi, 0);
 855					*rx++ = readl_relaxed(rx_reg);
 856					dev_vdbg(&spi->dev, "read-%d %08x\n",
 857						    word_len, *(rx - 1));
 858					if (mcspi_wait_for_reg_bit(chstat_reg,
 859						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 860						dev_err(&spi->dev,
 861							"RXS timed out\n");
 862						goto out;
 863					}
 864					c = 0;
 865				} else if (c == 0 && tx == NULL) {
 866					omap2_mcspi_set_enable(spi, 0);
 867				}
 868
 869				*rx++ = readl_relaxed(rx_reg);
 870				dev_vdbg(&spi->dev, "read-%d %08x\n",
 871						word_len, *(rx - 1));
 872			}
 873			/* Add word delay between each word */
 874			spi_delay_exec(&xfer->word_delay, xfer);
 875		} while (c >= 4);
 876	}
 877
 878	/* for TX_ONLY mode, be sure all words have shifted out */
 879	if (xfer->rx_buf == NULL) {
 880		if (mcspi_wait_for_reg_bit(chstat_reg,
 881				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 882			dev_err(&spi->dev, "TXS timed out\n");
 883		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 884				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 885			dev_err(&spi->dev, "EOT timed out\n");
 886
 887		/* disable chan to purge rx datas received in TX_ONLY transfer,
 888		 * otherwise these rx datas will affect the direct following
 889		 * RX_ONLY transfer.
 890		 */
 891		omap2_mcspi_set_enable(spi, 0);
 892	}
 893out:
 894	omap2_mcspi_set_enable(spi, 1);
 895	return count - c;
 896}
 897
 898static u32 omap2_mcspi_calc_divisor(u32 speed_hz, u32 ref_clk_hz)
 899{
 900	u32 div;
 901
 902	for (div = 0; div < 15; div++)
 903		if (speed_hz >= (ref_clk_hz >> div))
 904			return div;
 905
 906	return 15;
 907}
 908
 909/* called only when no transfer is active to this device */
 910static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 911		struct spi_transfer *t)
 912{
 913	struct omap2_mcspi_cs *cs = spi->controller_state;
 914	struct omap2_mcspi *mcspi;
 915	u32 ref_clk_hz, l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 
 916	u8 word_len = spi->bits_per_word;
 917	u32 speed_hz = spi->max_speed_hz;
 918
 919	mcspi = spi_controller_get_devdata(spi->controller);
 
 920
 921	if (t != NULL && t->bits_per_word)
 922		word_len = t->bits_per_word;
 923
 924	cs->word_len = word_len;
 925
 926	if (t && t->speed_hz)
 927		speed_hz = t->speed_hz;
 928
 929	ref_clk_hz = mcspi->ref_clk_hz;
 930	speed_hz = min_t(u32, speed_hz, ref_clk_hz);
 931	if (speed_hz < (ref_clk_hz / OMAP2_MCSPI_MAX_DIVIDER)) {
 932		clkd = omap2_mcspi_calc_divisor(speed_hz, ref_clk_hz);
 933		speed_hz = ref_clk_hz >> clkd;
 934		clkg = 0;
 935	} else {
 936		div = (ref_clk_hz + speed_hz - 1) / speed_hz;
 937		speed_hz = ref_clk_hz / div;
 938		clkd = (div - 1) & 0xf;
 939		extclk = (div - 1) >> 4;
 940		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 941	}
 942
 943	l = mcspi_cached_chconf0(spi);
 944
 945	/* standard 4-wire host mode:  SCK, MOSI/out, MISO/in, nCS
 946	 * REVISIT: this controller could support SPI_3WIRE mode.
 947	 */
 948	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 949		l &= ~OMAP2_MCSPI_CHCONF_IS;
 950		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 951		l |= OMAP2_MCSPI_CHCONF_DPE0;
 952	} else {
 953		l |= OMAP2_MCSPI_CHCONF_IS;
 954		l |= OMAP2_MCSPI_CHCONF_DPE1;
 955		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 956	}
 957
 958	/* wordlength */
 959	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 960	l |= (word_len - 1) << 7;
 961
 962	/* set chipselect polarity; manage with FORCE */
 963	if (!(spi->mode & SPI_CS_HIGH))
 964		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 965	else
 966		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 967
 968	/* set clock divisor */
 969	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 970	l |= clkd << 2;
 971
 972	/* set clock granularity */
 973	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 974	l |= clkg;
 975	if (clkg) {
 976		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 977		cs->chctrl0 |= extclk << 8;
 978		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 979	}
 980
 981	/* set SPI mode 0..3 */
 982	if (spi->mode & SPI_CPOL)
 983		l |= OMAP2_MCSPI_CHCONF_POL;
 984	else
 985		l &= ~OMAP2_MCSPI_CHCONF_POL;
 986	if (spi->mode & SPI_CPHA)
 987		l |= OMAP2_MCSPI_CHCONF_PHA;
 988	else
 989		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 990
 991	mcspi_write_chconf0(spi, l);
 992
 993	cs->mode = spi->mode;
 994
 995	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 996			speed_hz,
 997			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 998			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 999
1000	return 0;
1001}
1002
1003/*
1004 * Note that we currently allow DMA only if we get a channel
1005 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
1006 */
1007static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
1008				   struct omap2_mcspi_dma *mcspi_dma)
1009{
1010	int ret = 0;
1011
1012	mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
1013					     mcspi_dma->dma_rx_ch_name);
1014	if (IS_ERR(mcspi_dma->dma_rx)) {
1015		ret = PTR_ERR(mcspi_dma->dma_rx);
1016		mcspi_dma->dma_rx = NULL;
1017		goto no_dma;
1018	}
1019
1020	mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
1021					     mcspi_dma->dma_tx_ch_name);
1022	if (IS_ERR(mcspi_dma->dma_tx)) {
1023		ret = PTR_ERR(mcspi_dma->dma_tx);
1024		mcspi_dma->dma_tx = NULL;
1025		dma_release_channel(mcspi_dma->dma_rx);
1026		mcspi_dma->dma_rx = NULL;
1027	}
1028
1029	init_completion(&mcspi_dma->dma_rx_completion);
1030	init_completion(&mcspi_dma->dma_tx_completion);
1031
1032no_dma:
1033	return ret;
1034}
1035
1036static void omap2_mcspi_release_dma(struct spi_controller *ctlr)
1037{
1038	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1039	struct omap2_mcspi_dma	*mcspi_dma;
1040	int i;
 
1041
1042	for (i = 0; i < ctlr->num_chipselect; i++) {
1043		mcspi_dma = &mcspi->dma_channels[i];
 
 
 
1044
1045		if (mcspi_dma->dma_rx) {
1046			dma_release_channel(mcspi_dma->dma_rx);
1047			mcspi_dma->dma_rx = NULL;
1048		}
1049		if (mcspi_dma->dma_tx) {
1050			dma_release_channel(mcspi_dma->dma_tx);
1051			mcspi_dma->dma_tx = NULL;
1052		}
1053	}
1054}
1055
1056static void omap2_mcspi_cleanup(struct spi_device *spi)
1057{
1058	struct omap2_mcspi_cs	*cs;
1059
1060	if (spi->controller_state) {
1061		/* Unlink controller state from context save list */
1062		cs = spi->controller_state;
1063		list_del(&cs->node);
1064
1065		kfree(cs);
1066	}
 
1067}
1068
1069static int omap2_mcspi_setup(struct spi_device *spi)
1070{
1071	bool			initial_setup = false;
1072	int			ret;
1073	struct omap2_mcspi	*mcspi = spi_controller_get_devdata(spi->controller);
1074	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 
1075	struct omap2_mcspi_cs	*cs = spi->controller_state;
1076
 
 
1077	if (!cs) {
1078		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1079		if (!cs)
1080			return -ENOMEM;
1081		cs->base = mcspi->base + spi_get_chipselect(spi, 0) * 0x14;
1082		cs->phys = mcspi->phys + spi_get_chipselect(spi, 0) * 0x14;
1083		cs->mode = 0;
1084		cs->chconf0 = 0;
1085		cs->chctrl0 = 0;
1086		spi->controller_state = cs;
1087		/* Link this to context save list */
1088		list_add_tail(&cs->node, &ctx->cs);
1089		initial_setup = true;
1090	}
1091
1092	ret = pm_runtime_resume_and_get(mcspi->dev);
1093	if (ret < 0) {
1094		if (initial_setup)
1095			omap2_mcspi_cleanup(spi);
 
1096
 
 
1097		return ret;
1098	}
1099
1100	ret = omap2_mcspi_setup_transfer(spi, NULL);
1101	if (ret && initial_setup)
1102		omap2_mcspi_cleanup(spi);
1103
1104	pm_runtime_mark_last_busy(mcspi->dev);
1105	pm_runtime_put_autosuspend(mcspi->dev);
1106
1107	return ret;
1108}
1109
1110static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1111{
1112	struct omap2_mcspi *mcspi = data;
1113	u32 irqstat;
1114
1115	irqstat	= mcspi_read_reg(mcspi->ctlr, OMAP2_MCSPI_IRQSTATUS);
1116	if (!irqstat)
1117		return IRQ_NONE;
1118
1119	/* Disable IRQ and wakeup target xfer task */
1120	mcspi_write_reg(mcspi->ctlr, OMAP2_MCSPI_IRQENABLE, 0);
1121	if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1122		complete(&mcspi->txdone);
1123
1124	return IRQ_HANDLED;
1125}
 
 
1126
1127static int omap2_mcspi_target_abort(struct spi_controller *ctlr)
1128{
1129	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1130	struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1131
1132	mcspi->target_aborted = true;
1133	complete(&mcspi_dma->dma_rx_completion);
1134	complete(&mcspi_dma->dma_tx_completion);
1135	complete(&mcspi->txdone);
1136
1137	return 0;
 
 
 
 
 
 
 
 
1138}
1139
1140static int omap2_mcspi_transfer_one(struct spi_controller *ctlr,
1141				    struct spi_device *spi,
1142				    struct spi_transfer *t)
1143{
1144
1145	/* We only enable one channel at a time -- the one whose message is
1146	 * -- although this controller would gladly
1147	 * arbitrate among multiple channels.  This corresponds to "single
1148	 * channel" host mode.  As a side effect, we need to manage the
1149	 * chipselect with the FORCE bit ... CS != channel enable.
1150	 */
1151
1152	struct omap2_mcspi		*mcspi;
 
 
1153	struct omap2_mcspi_dma		*mcspi_dma;
 
1154	struct omap2_mcspi_cs		*cs;
1155	struct omap2_mcspi_device_config *cd;
1156	int				par_override = 0;
1157	int				status = 0;
1158	u32				chconf;
1159
1160	mcspi = spi_controller_get_devdata(ctlr);
1161	mcspi_dma = mcspi->dma_channels + spi_get_chipselect(spi, 0);
 
1162	cs = spi->controller_state;
1163	cd = spi->controller_data;
1164
1165	/*
1166	 * The target driver could have changed spi->mode in which case
1167	 * it will be different from cs->mode (the current hardware setup).
1168	 * If so, set par_override (even though its not a parity issue) so
1169	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1170	 * with the correct mode on the first iteration of the loop below.
1171	 */
1172	if (spi->mode != cs->mode)
1173		par_override = 1;
1174
1175	omap2_mcspi_set_enable(spi, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1176
1177	if (spi_get_csgpiod(spi, 0))
1178		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1179
1180	if (par_override ||
1181	    (t->speed_hz != spi->max_speed_hz) ||
1182	    (t->bits_per_word != spi->bits_per_word)) {
1183		par_override = 1;
1184		status = omap2_mcspi_setup_transfer(spi, t);
1185		if (status < 0)
1186			goto out;
1187		if (t->speed_hz == spi->max_speed_hz &&
1188		    t->bits_per_word == spi->bits_per_word)
1189			par_override = 0;
1190	}
1191
1192	chconf = mcspi_cached_chconf0(spi);
1193	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1194	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
 
1195
1196	if (t->tx_buf == NULL)
1197		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1198	else if (t->rx_buf == NULL)
1199		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1200
1201	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1202		/* Turbo mode is for more than one word */
1203		if (t->len > ((cs->word_len + 7) >> 3))
1204			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1205	}
1206
1207	mcspi_write_chconf0(spi, chconf);
 
 
 
 
 
 
 
 
 
1208
1209	if (t->len) {
1210		unsigned	count;
1211
1212		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1213		    spi_xfer_is_dma_mapped(ctlr, spi, t))
1214			omap2_mcspi_set_fifo(spi, t, 1);
1215
1216		omap2_mcspi_set_enable(spi, 1);
 
 
1217
1218		/* RX_ONLY mode needs dummy data in TX reg */
1219		if (t->tx_buf == NULL)
1220			writel_relaxed(0, cs->base
1221					+ OMAP2_MCSPI_TX0);
1222
1223		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1224		    spi_xfer_is_dma_mapped(ctlr, spi, t))
1225			count = omap2_mcspi_txrx_dma(spi, t);
1226		else
1227			count = omap2_mcspi_txrx_pio(spi, t);
 
 
 
 
 
 
1228
1229		if (count != t->len) {
1230			status = -EIO;
1231			goto out;
 
1232		}
1233	}
1234
1235	omap2_mcspi_set_enable(spi, 0);
 
1236
1237	if (mcspi->fifo_depth > 0)
1238		omap2_mcspi_set_fifo(spi, t, 0);
 
 
 
1239
1240out:
 
 
 
 
1241	/* Restore defaults if they were overriden */
1242	if (par_override) {
1243		par_override = 0;
1244		status = omap2_mcspi_setup_transfer(spi, NULL);
1245	}
1246
1247	omap2_mcspi_set_enable(spi, 0);
 
1248
1249	if (spi_get_csgpiod(spi, 0))
1250		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
 
 
 
 
 
 
 
1251
1252	if (mcspi->fifo_depth > 0 && t)
1253		omap2_mcspi_set_fifo(spi, t, 0);
1254
1255	return status;
1256}
1257
1258static int omap2_mcspi_prepare_message(struct spi_controller *ctlr,
1259				       struct spi_message *msg)
1260{
1261	struct omap2_mcspi	*mcspi = spi_controller_get_devdata(ctlr);
1262	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1263	struct omap2_mcspi_cs	*cs;
1264	struct spi_transfer	*tr;
1265	u8 bits_per_word;
1266
1267	/*
1268	 * The conditions are strict, it is mandatory to check each transfer of the list to see if
1269	 * multi-mode is applicable.
1270	 */
1271	mcspi->use_multi_mode = true;
1272	list_for_each_entry(tr, &msg->transfers, transfer_list) {
1273		if (!tr->bits_per_word)
1274			bits_per_word = msg->spi->bits_per_word;
1275		else
1276			bits_per_word = tr->bits_per_word;
1277
1278		/*
1279		 * Check if this transfer contains only one word;
1280		 */
1281		if (bits_per_word < 8 && tr->len == 1) {
1282			/* multi-mode is applicable, only one word (1..7 bits) */
1283		} else if (bits_per_word >= 8 && tr->len == bits_per_word / 8) {
1284			/* multi-mode is applicable, only one word (8..32 bits) */
1285		} else {
1286			/* multi-mode is not applicable: more than one word in the transfer */
1287			mcspi->use_multi_mode = false;
 
 
 
 
 
 
 
 
 
1288		}
1289
1290		/* Check if transfer asks to change the CS status after the transfer */
1291		if (!tr->cs_change)
1292			mcspi->use_multi_mode = false;
1293
1294		/*
1295		 * If at least one message is not compatible, switch back to single mode
1296		 *
1297		 * The bits_per_word of certain transfer can be different, but it will have no
1298		 * impact on the signal itself.
1299		 */
1300		if (!mcspi->use_multi_mode)
1301			break;
1302	}
1303
1304	omap2_mcspi_set_mode(ctlr);
1305
1306	/* In single mode only a single channel can have the FORCE bit enabled
1307	 * in its chconf0 register.
1308	 * Scan all channels and disable them except the current one.
1309	 * A FORCE can remain from a last transfer having cs_change enabled
1310	 *
1311	 * In multi mode all FORCE bits must be disabled.
1312	 */
1313	list_for_each_entry(cs, &ctx->cs, node) {
1314		if (msg->spi->controller_state == cs && !mcspi->use_multi_mode) {
1315			continue;
1316		}
1317
1318		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1319			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1320			writel_relaxed(cs->chconf0,
1321					cs->base + OMAP2_MCSPI_CHCONF0);
1322			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1323		}
1324	}
1325
 
 
1326	return 0;
1327}
1328
1329static bool omap2_mcspi_can_dma(struct spi_controller *ctlr,
1330				struct spi_device *spi,
1331				struct spi_transfer *xfer)
1332{
1333	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
1334	struct omap2_mcspi_dma *mcspi_dma =
1335		&mcspi->dma_channels[spi_get_chipselect(spi, 0)];
1336
1337	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1338		return false;
1339
1340	if (spi_controller_is_target(ctlr))
1341		return true;
1342
1343	ctlr->dma_rx = mcspi_dma->dma_rx;
1344	ctlr->dma_tx = mcspi_dma->dma_tx;
1345
1346	return (xfer->len >= DMA_MIN_BYTES);
1347}
1348
1349static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1350{
1351	struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
1352	struct omap2_mcspi_dma *mcspi_dma =
1353		&mcspi->dma_channels[spi_get_chipselect(spi, 0)];
1354
1355	if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1356		return mcspi->max_xfer_len;
1357
1358	return SIZE_MAX;
1359}
1360
1361static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1362{
1363	struct spi_controller	*ctlr = mcspi->ctlr;
1364	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1365	int			ret = 0;
1366
1367	ret = pm_runtime_resume_and_get(mcspi->dev);
1368	if (ret < 0)
1369		return ret;
1370
1371	mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE,
1372			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1373	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1374
1375	omap2_mcspi_set_mode(ctlr);
1376	pm_runtime_mark_last_busy(mcspi->dev);
1377	pm_runtime_put_autosuspend(mcspi->dev);
1378	return 0;
1379}
1380
1381static int omap_mcspi_runtime_suspend(struct device *dev)
1382{
1383	int error;
1384
1385	error = pinctrl_pm_select_idle_state(dev);
1386	if (error)
1387		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1388
1389	return 0;
1390}
1391
1392/*
1393 * When SPI wake up from off-mode, CS is in activate state. If it was in
1394 * inactive state when driver was suspend, then force it to inactive state at
1395 * wake up.
1396 */
1397static int omap_mcspi_runtime_resume(struct device *dev)
1398{
1399	struct spi_controller *ctlr = dev_get_drvdata(dev);
1400	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1401	struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1402	struct omap2_mcspi_cs *cs;
1403	int error;
1404
1405	error = pinctrl_pm_select_default_state(dev);
1406	if (error)
1407		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1408
1409	/* McSPI: context restore */
1410	mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1411	mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1412
1413	list_for_each_entry(cs, &ctx->cs, node) {
1414		/*
1415		 * We need to toggle CS state for OMAP take this
1416		 * change in account.
1417		 */
1418		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1419			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1420			writel_relaxed(cs->chconf0,
1421				       cs->base + OMAP2_MCSPI_CHCONF0);
1422			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1423			writel_relaxed(cs->chconf0,
1424				       cs->base + OMAP2_MCSPI_CHCONF0);
1425		} else {
1426			writel_relaxed(cs->chconf0,
1427				       cs->base + OMAP2_MCSPI_CHCONF0);
1428		}
1429	}
1430
1431	return 0;
1432}
1433
1434static struct omap2_mcspi_platform_config omap2_pdata = {
1435	.regs_offset = 0,
1436};
1437
1438static struct omap2_mcspi_platform_config omap4_pdata = {
1439	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1440};
1441
1442static struct omap2_mcspi_platform_config am654_pdata = {
1443	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1444	.max_xfer_len = SZ_4K - 1,
1445};
1446
1447static const struct of_device_id omap_mcspi_of_match[] = {
1448	{
1449		.compatible = "ti,omap2-mcspi",
1450		.data = &omap2_pdata,
1451	},
1452	{
1453		.compatible = "ti,omap4-mcspi",
1454		.data = &omap4_pdata,
1455	},
1456	{
1457		.compatible = "ti,am654-mcspi",
1458		.data = &am654_pdata,
1459	},
1460	{ },
1461};
1462MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1463
1464static int omap2_mcspi_probe(struct platform_device *pdev)
1465{
1466	struct spi_controller	*ctlr;
1467	const struct omap2_mcspi_platform_config *pdata;
1468	struct omap2_mcspi	*mcspi;
1469	struct resource		*r;
1470	int			status = 0, i;
1471	u32			regs_offset = 0;
 
1472	struct device_node	*node = pdev->dev.of_node;
1473	const struct of_device_id *match;
1474
1475	if (of_property_read_bool(node, "spi-slave"))
1476		ctlr = spi_alloc_target(&pdev->dev, sizeof(*mcspi));
1477	else
1478		ctlr = spi_alloc_host(&pdev->dev, sizeof(*mcspi));
1479	if (!ctlr)
1480		return -ENOMEM;
 
1481
1482	/* the spi->mode bits understood by this driver: */
1483	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1484	ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1485	ctlr->setup = omap2_mcspi_setup;
1486	ctlr->auto_runtime_pm = true;
1487	ctlr->prepare_message = omap2_mcspi_prepare_message;
1488	ctlr->can_dma = omap2_mcspi_can_dma;
1489	ctlr->transfer_one = omap2_mcspi_transfer_one;
1490	ctlr->set_cs = omap2_mcspi_set_cs;
1491	ctlr->cleanup = omap2_mcspi_cleanup;
1492	ctlr->target_abort = omap2_mcspi_target_abort;
1493	ctlr->dev.of_node = node;
1494	ctlr->use_gpio_descriptors = true;
1495
1496	platform_set_drvdata(pdev, ctlr);
1497
1498	mcspi = spi_controller_get_devdata(ctlr);
1499	mcspi->ctlr = ctlr;
1500
1501	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1502	if (match) {
1503		u32 num_cs = 1; /* default number of chipselect */
1504		pdata = match->data;
1505
1506		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1507		ctlr->num_chipselect = num_cs;
1508		if (of_property_read_bool(node, "ti,pindir-d0-out-d1-in"))
 
1509			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1510	} else {
1511		pdata = dev_get_platdata(&pdev->dev);
1512		ctlr->num_chipselect = pdata->num_cs;
 
 
1513		mcspi->pin_dir = pdata->pin_dir;
1514	}
1515	regs_offset = pdata->regs_offset;
1516	if (pdata->max_xfer_len) {
1517		mcspi->max_xfer_len = pdata->max_xfer_len;
1518		ctlr->max_transfer_size = omap2_mcspi_max_xfer_size;
 
 
1519	}
1520
1521	mcspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
 
 
 
 
1522	if (IS_ERR(mcspi->base)) {
1523		status = PTR_ERR(mcspi->base);
1524		goto free_ctlr;
1525	}
1526	mcspi->phys = r->start + regs_offset;
1527	mcspi->base += regs_offset;
1528
1529	mcspi->dev = &pdev->dev;
1530
1531	INIT_LIST_HEAD(&mcspi->ctx.cs);
1532
1533	mcspi->dma_channels = devm_kcalloc(&pdev->dev, ctlr->num_chipselect,
1534					   sizeof(struct omap2_mcspi_dma),
1535					   GFP_KERNEL);
1536	if (mcspi->dma_channels == NULL) {
1537		status = -ENOMEM;
1538		goto free_ctlr;
1539	}
1540
1541	for (i = 0; i < ctlr->num_chipselect; i++) {
1542		sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1543		sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1544
1545		status = omap2_mcspi_request_dma(mcspi,
1546						 &mcspi->dma_channels[i]);
1547		if (status == -EPROBE_DEFER)
1548			goto free_ctlr;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1549	}
1550
1551	status = platform_get_irq(pdev, 0);
1552	if (status < 0)
1553		goto free_ctlr;
1554	init_completion(&mcspi->txdone);
1555	status = devm_request_irq(&pdev->dev, status,
1556				  omap2_mcspi_irq_handler, 0, pdev->name,
1557				  mcspi);
1558	if (status) {
1559		dev_err(&pdev->dev, "Cannot request IRQ");
1560		goto free_ctlr;
1561	}
1562
1563	mcspi->ref_clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
1564	if (IS_ERR(mcspi->ref_clk)) {
1565		status = PTR_ERR(mcspi->ref_clk);
1566		dev_err_probe(&pdev->dev, status, "Failed to get ref_clk");
1567		goto free_ctlr;
1568	}
1569	if (mcspi->ref_clk)
1570		mcspi->ref_clk_hz = clk_get_rate(mcspi->ref_clk);
1571	else
1572		mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ;
1573	ctlr->max_speed_hz = mcspi->ref_clk_hz;
1574	ctlr->min_speed_hz = mcspi->ref_clk_hz >> 15;
1575
1576	pm_runtime_use_autosuspend(&pdev->dev);
1577	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1578	pm_runtime_enable(&pdev->dev);
1579
1580	status = omap2_mcspi_controller_setup(mcspi);
1581	if (status < 0)
1582		goto disable_pm;
1583
1584	status = devm_spi_register_controller(&pdev->dev, ctlr);
1585	if (status < 0)
1586		goto disable_pm;
1587
1588	return status;
1589
1590disable_pm:
1591	pm_runtime_dont_use_autosuspend(&pdev->dev);
1592	pm_runtime_put_sync(&pdev->dev);
1593	pm_runtime_disable(&pdev->dev);
1594free_ctlr:
1595	omap2_mcspi_release_dma(ctlr);
1596	spi_controller_put(ctlr);
1597	return status;
1598}
1599
1600static void omap2_mcspi_remove(struct platform_device *pdev)
1601{
1602	struct spi_controller *ctlr = platform_get_drvdata(pdev);
1603	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1604
1605	omap2_mcspi_release_dma(ctlr);
1606
1607	pm_runtime_dont_use_autosuspend(mcspi->dev);
1608	pm_runtime_put_sync(mcspi->dev);
1609	pm_runtime_disable(&pdev->dev);
 
 
1610}
1611
1612/* work with hotplug and coldplug */
1613MODULE_ALIAS("platform:omap2_mcspi");
1614
1615static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1616{
1617	struct spi_controller *ctlr = dev_get_drvdata(dev);
1618	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1619	int error;
1620
1621	error = pinctrl_pm_select_sleep_state(dev);
1622	if (error)
1623		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1624			 __func__, error);
1625
1626	error = spi_controller_suspend(ctlr);
1627	if (error)
1628		dev_warn(mcspi->dev, "%s: controller suspend failed: %i\n",
1629			 __func__, error);
1630
1631	return pm_runtime_force_suspend(dev);
1632}
1633
1634static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1635{
1636	struct spi_controller *ctlr = dev_get_drvdata(dev);
1637	struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1638	int error;
1639
1640	error = spi_controller_resume(ctlr);
1641	if (error)
1642		dev_warn(mcspi->dev, "%s: controller resume failed: %i\n",
1643			 __func__, error);
1644
1645	return pm_runtime_force_resume(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1646}
 
 
 
1647
1648static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1649	SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1650				omap2_mcspi_resume)
1651	.runtime_suspend	= omap_mcspi_runtime_suspend,
1652	.runtime_resume		= omap_mcspi_runtime_resume,
1653};
1654
1655static struct platform_driver omap2_mcspi_driver = {
1656	.driver = {
1657		.name =		"omap2_mcspi",
 
1658		.pm =		&omap2_mcspi_pm_ops,
1659		.of_match_table = omap_mcspi_of_match,
1660	},
1661	.probe =	omap2_mcspi_probe,
1662	.remove =	omap2_mcspi_remove,
1663};
1664
1665module_platform_driver(omap2_mcspi_driver);
1666MODULE_DESCRIPTION("OMAP2 McSPI controller driver");
1667MODULE_LICENSE("GPL");
v3.15
 
   1/*
   2 * OMAP2 McSPI controller driver
   3 *
   4 * Copyright (C) 2005, 2006 Nokia Corporation
   5 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   6 *		Juha Yrj�l� <juha.yrjola@nokia.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License as published by
  10 * the Free Software Foundation; either version 2 of the License, or
  11 * (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21 *
  22 */
  23
  24#include <linux/kernel.h>
  25#include <linux/interrupt.h>
  26#include <linux/module.h>
  27#include <linux/device.h>
  28#include <linux/delay.h>
  29#include <linux/dma-mapping.h>
  30#include <linux/dmaengine.h>
  31#include <linux/omap-dma.h>
  32#include <linux/platform_device.h>
  33#include <linux/err.h>
  34#include <linux/clk.h>
  35#include <linux/io.h>
  36#include <linux/slab.h>
  37#include <linux/pm_runtime.h>
  38#include <linux/of.h>
  39#include <linux/of_device.h>
  40#include <linux/gcd.h>
  41
  42#include <linux/spi/spi.h>
  43
 
 
  44#include <linux/platform_data/spi-omap2-mcspi.h>
  45
  46#define OMAP2_MCSPI_MAX_FREQ		48000000
  47#define OMAP2_MCSPI_MAX_DIVIDER		4096
  48#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  49#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  50#define SPI_AUTOSUSPEND_TIMEOUT		2000
  51
  52#define OMAP2_MCSPI_REVISION		0x00
  53#define OMAP2_MCSPI_SYSSTATUS		0x14
  54#define OMAP2_MCSPI_IRQSTATUS		0x18
  55#define OMAP2_MCSPI_IRQENABLE		0x1c
  56#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  57#define OMAP2_MCSPI_SYST		0x24
  58#define OMAP2_MCSPI_MODULCTRL		0x28
  59#define OMAP2_MCSPI_XFERLEVEL		0x7c
  60
  61/* per-channel banks, 0x14 bytes each, first is: */
  62#define OMAP2_MCSPI_CHCONF0		0x2c
  63#define OMAP2_MCSPI_CHSTAT0		0x30
  64#define OMAP2_MCSPI_CHCTRL0		0x34
  65#define OMAP2_MCSPI_TX0			0x38
  66#define OMAP2_MCSPI_RX0			0x3c
  67
  68/* per-register bitmasks: */
  69#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  70
  71#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  72#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  73#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  74
  75#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  76#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  77#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  78#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  79#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  80#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  81#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  82#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  83#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  84#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  85#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  86#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  87#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  88#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  89#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  90#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  91#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  92#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  93
  94#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  95#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  96#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  97#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  98
  99#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
 100#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
 101
 102#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
 103
 104/* We have 2 DMA channels per CS, one for RX and one for TX */
 105struct omap2_mcspi_dma {
 106	struct dma_chan *dma_tx;
 107	struct dma_chan *dma_rx;
 108
 109	int dma_tx_sync_dev;
 110	int dma_rx_sync_dev;
 111
 112	struct completion dma_tx_completion;
 113	struct completion dma_rx_completion;
 114
 115	char dma_rx_ch_name[14];
 116	char dma_tx_ch_name[14];
 117};
 118
 119/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 120 * cache operations; better heuristics consider wordsize and bitrate.
 121 */
 122#define DMA_MIN_BYTES			160
 123
 124
 125/*
 126 * Used for context save and restore, structure members to be updated whenever
 127 * corresponding registers are modified.
 128 */
 129struct omap2_mcspi_regs {
 130	u32 modulctrl;
 131	u32 wakeupenable;
 132	struct list_head cs;
 133};
 134
 135struct omap2_mcspi {
 136	struct spi_master	*master;
 
 137	/* Virtual base address of the controller */
 138	void __iomem		*base;
 139	unsigned long		phys;
 140	/* SPI1 has 4 channels, while SPI2 has 2 */
 141	struct omap2_mcspi_dma	*dma_channels;
 142	struct device		*dev;
 143	struct omap2_mcspi_regs ctx;
 
 144	int			fifo_depth;
 
 145	unsigned int		pin_dir:1;
 
 
 
 146};
 147
 148struct omap2_mcspi_cs {
 149	void __iomem		*base;
 150	unsigned long		phys;
 151	int			word_len;
 
 152	struct list_head	node;
 153	/* Context save and restore shadow register */
 154	u32			chconf0, chctrl0;
 155};
 156
 157static inline void mcspi_write_reg(struct spi_master *master,
 158		int idx, u32 val)
 159{
 160	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 161
 162	writel_relaxed(val, mcspi->base + idx);
 163}
 164
 165static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 166{
 167	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 168
 169	return readl_relaxed(mcspi->base + idx);
 170}
 171
 172static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 173		int idx, u32 val)
 174{
 175	struct omap2_mcspi_cs	*cs = spi->controller_state;
 176
 177	writel_relaxed(val, cs->base +  idx);
 178}
 179
 180static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 181{
 182	struct omap2_mcspi_cs	*cs = spi->controller_state;
 183
 184	return readl_relaxed(cs->base + idx);
 185}
 186
 187static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 188{
 189	struct omap2_mcspi_cs *cs = spi->controller_state;
 190
 191	return cs->chconf0;
 192}
 193
 194static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 195{
 196	struct omap2_mcspi_cs *cs = spi->controller_state;
 197
 198	cs->chconf0 = val;
 199	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 200	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 201}
 202
 203static inline int mcspi_bytes_per_word(int word_len)
 204{
 205	if (word_len <= 8)
 206		return 1;
 207	else if (word_len <= 16)
 208		return 2;
 209	else /* word_len <= 32 */
 210		return 4;
 211}
 212
 213static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 214		int is_read, int enable)
 215{
 216	u32 l, rw;
 217
 218	l = mcspi_cached_chconf0(spi);
 219
 220	if (is_read) /* 1 is read, 0 write */
 221		rw = OMAP2_MCSPI_CHCONF_DMAR;
 222	else
 223		rw = OMAP2_MCSPI_CHCONF_DMAW;
 224
 225	if (enable)
 226		l |= rw;
 227	else
 228		l &= ~rw;
 229
 230	mcspi_write_chconf0(spi, l);
 231}
 232
 233static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 234{
 235	struct omap2_mcspi_cs *cs = spi->controller_state;
 236	u32 l;
 237
 238	l = cs->chctrl0;
 239	if (enable)
 240		l |= OMAP2_MCSPI_CHCTRL_EN;
 241	else
 242		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 243	cs->chctrl0 = l;
 244	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 245	/* Flash post-writes */
 246	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 247}
 248
 249static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 250{
 
 251	u32 l;
 252
 253	l = mcspi_cached_chconf0(spi);
 254	if (cs_active)
 255		l |= OMAP2_MCSPI_CHCONF_FORCE;
 256	else
 257		l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 258
 259	mcspi_write_chconf0(spi, l);
 
 
 260}
 261
 262static void omap2_mcspi_set_master_mode(struct spi_master *master)
 263{
 264	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 265	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 266	u32 l;
 267
 268	/*
 269	 * Setup when switching from (reset default) slave mode
 270	 * to single-channel master mode
 271	 */
 272	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 273	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
 274	l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 275	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 
 
 
 
 
 
 
 
 
 
 276
 277	ctx->modulctrl = l;
 278}
 279
 280static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 281				struct spi_transfer *t, int enable)
 282{
 283	struct spi_master *master = spi->master;
 284	struct omap2_mcspi_cs *cs = spi->controller_state;
 285	struct omap2_mcspi *mcspi;
 286	unsigned int wcnt;
 287	int max_fifo_depth, fifo_depth, bytes_per_word;
 288	u32 chconf, xferlevel;
 289
 290	mcspi = spi_master_get_devdata(master);
 291
 292	chconf = mcspi_cached_chconf0(spi);
 293	if (enable) {
 294		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 295		if (t->len % bytes_per_word != 0)
 296			goto disable_fifo;
 297
 298		if (t->rx_buf != NULL && t->tx_buf != NULL)
 299			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 300		else
 301			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 302
 303		fifo_depth = gcd(t->len, max_fifo_depth);
 304		if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
 305			goto disable_fifo;
 306
 307		wcnt = t->len / bytes_per_word;
 308		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 309			goto disable_fifo;
 310
 311		xferlevel = wcnt << 16;
 312		if (t->rx_buf != NULL) {
 313			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 314			xferlevel |= (fifo_depth - 1) << 8;
 315		}
 
 316		if (t->tx_buf != NULL) {
 317			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 318			xferlevel |= fifo_depth - 1;
 319		}
 320
 321		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 322		mcspi_write_chconf0(spi, chconf);
 323		mcspi->fifo_depth = fifo_depth;
 324
 325		return;
 326	}
 327
 328disable_fifo:
 329	if (t->rx_buf != NULL)
 330		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 331	else
 
 332		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 333
 334	mcspi_write_chconf0(spi, chconf);
 335	mcspi->fifo_depth = 0;
 336}
 337
 338static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 339{
 340	struct spi_master	*spi_cntrl = mcspi->master;
 341	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 342	struct omap2_mcspi_cs	*cs;
 343
 344	/* McSPI: context restore */
 345	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
 346	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
 347
 348	list_for_each_entry(cs, &ctx->cs, node)
 349		writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 350}
 351
 352static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 353{
 354	unsigned long timeout;
 355
 356	timeout = jiffies + msecs_to_jiffies(1000);
 357	while (!(readl_relaxed(reg) & bit)) {
 358		if (time_after(jiffies, timeout)) {
 359			if (!(readl_relaxed(reg) & bit))
 360				return -ETIMEDOUT;
 361			else
 362				return 0;
 363		}
 364		cpu_relax();
 365	}
 366	return 0;
 367}
 368
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 369static void omap2_mcspi_rx_callback(void *data)
 370{
 371	struct spi_device *spi = data;
 372	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 373	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 374
 375	/* We must disable the DMA RX request */
 376	omap2_mcspi_set_dma_req(spi, 1, 0);
 377
 378	complete(&mcspi_dma->dma_rx_completion);
 379}
 380
 381static void omap2_mcspi_tx_callback(void *data)
 382{
 383	struct spi_device *spi = data;
 384	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 385	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 386
 387	/* We must disable the DMA TX request */
 388	omap2_mcspi_set_dma_req(spi, 0, 0);
 389
 390	complete(&mcspi_dma->dma_tx_completion);
 391}
 392
 393static void omap2_mcspi_tx_dma(struct spi_device *spi,
 394				struct spi_transfer *xfer,
 395				struct dma_slave_config cfg)
 396{
 397	struct omap2_mcspi	*mcspi;
 398	struct omap2_mcspi_dma  *mcspi_dma;
 399	unsigned int		count;
 
 
 
 400
 401	mcspi = spi_master_get_devdata(spi->master);
 402	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 403	count = xfer->len;
 404
 405	if (mcspi_dma->dma_tx) {
 406		struct dma_async_tx_descriptor *tx;
 407		struct scatterlist sg;
 408
 409		dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 410
 411		sg_init_table(&sg, 1);
 412		sg_dma_address(&sg) = xfer->tx_dma;
 413		sg_dma_len(&sg) = xfer->len;
 414
 415		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
 416		DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 417		if (tx) {
 418			tx->callback = omap2_mcspi_tx_callback;
 419			tx->callback_param = spi;
 420			dmaengine_submit(tx);
 421		} else {
 422			/* FIXME: fall back to PIO? */
 423		}
 424	}
 425	dma_async_issue_pending(mcspi_dma->dma_tx);
 426	omap2_mcspi_set_dma_req(spi, 0, 1);
 427
 428}
 429
 430static unsigned
 431omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 432				struct dma_slave_config cfg,
 433				unsigned es)
 434{
 435	struct omap2_mcspi	*mcspi;
 436	struct omap2_mcspi_dma  *mcspi_dma;
 437	unsigned int		count, dma_count;
 
 
 
 438	u32			l;
 439	int			elements = 0;
 440	int			word_len, element_count;
 441	struct omap2_mcspi_cs	*cs = spi->controller_state;
 442	mcspi = spi_master_get_devdata(spi->master);
 443	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 
 
 
 444	count = xfer->len;
 445	dma_count = xfer->len;
 446
 
 
 
 
 
 447	if (mcspi->fifo_depth == 0)
 448		dma_count -= es;
 449
 450	word_len = cs->word_len;
 451	l = mcspi_cached_chconf0(spi);
 452
 453	if (word_len <= 8)
 454		element_count = count;
 455	else if (word_len <= 16)
 456		element_count = count >> 1;
 457	else /* word_len <= 32 */
 458		element_count = count >> 2;
 459
 460	if (mcspi_dma->dma_rx) {
 461		struct dma_async_tx_descriptor *tx;
 462		struct scatterlist sg;
 463
 464		dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 465
 466		if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 467			dma_count -= es;
 468
 469		sg_init_table(&sg, 1);
 470		sg_dma_address(&sg) = xfer->rx_dma;
 471		sg_dma_len(&sg) = dma_count;
 472
 473		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
 474				DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
 475				DMA_CTRL_ACK);
 476		if (tx) {
 477			tx->callback = omap2_mcspi_rx_callback;
 478			tx->callback_param = spi;
 479			dmaengine_submit(tx);
 480		} else {
 481				/* FIXME: fall back to PIO? */
 482		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 483	}
 484
 485	dma_async_issue_pending(mcspi_dma->dma_rx);
 486	omap2_mcspi_set_dma_req(spi, 1, 1);
 487
 488	wait_for_completion(&mcspi_dma->dma_rx_completion);
 489	dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
 490			 DMA_FROM_DEVICE);
 
 
 
 
 
 
 491
 492	if (mcspi->fifo_depth > 0)
 493		return count;
 494
 
 
 
 
 495	omap2_mcspi_set_enable(spi, 0);
 496
 497	elements = element_count - 1;
 498
 499	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 500		elements--;
 501
 502		if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 503				   & OMAP2_MCSPI_CHSTAT_RXS)) {
 504			u32 w;
 505
 506			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 507			if (word_len <= 8)
 508				((u8 *)xfer->rx_buf)[elements++] = w;
 509			else if (word_len <= 16)
 510				((u16 *)xfer->rx_buf)[elements++] = w;
 511			else /* word_len <= 32 */
 512				((u32 *)xfer->rx_buf)[elements++] = w;
 513		} else {
 514			int bytes_per_word = mcspi_bytes_per_word(word_len);
 515			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 516			count -= (bytes_per_word << 1);
 517			omap2_mcspi_set_enable(spi, 1);
 518			return count;
 519		}
 520	}
 521	if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 522				& OMAP2_MCSPI_CHSTAT_RXS)) {
 523		u32 w;
 524
 525		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 526		if (word_len <= 8)
 527			((u8 *)xfer->rx_buf)[elements] = w;
 528		else if (word_len <= 16)
 529			((u16 *)xfer->rx_buf)[elements] = w;
 530		else /* word_len <= 32 */
 531			((u32 *)xfer->rx_buf)[elements] = w;
 532	} else {
 533		dev_err(&spi->dev, "DMA RX last word empty\n");
 534		count -= mcspi_bytes_per_word(word_len);
 535	}
 536	omap2_mcspi_set_enable(spi, 1);
 537	return count;
 538}
 539
 540static unsigned
 541omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 542{
 543	struct omap2_mcspi	*mcspi;
 544	struct omap2_mcspi_cs	*cs = spi->controller_state;
 545	struct omap2_mcspi_dma  *mcspi_dma;
 546	unsigned int		count;
 547	u32			l;
 548	u8			*rx;
 549	const u8		*tx;
 550	struct dma_slave_config	cfg;
 551	enum dma_slave_buswidth width;
 552	unsigned es;
 553	u32			burst;
 554	void __iomem		*chstat_reg;
 555	void __iomem            *irqstat_reg;
 556	int			wait_res;
 557
 558	mcspi = spi_master_get_devdata(spi->master);
 559	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 560	l = mcspi_cached_chconf0(spi);
 561
 562
 563	if (cs->word_len <= 8) {
 564		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 565		es = 1;
 566	} else if (cs->word_len <= 16) {
 567		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 568		es = 2;
 569	} else {
 570		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 571		es = 4;
 572	}
 573
 574	count = xfer->len;
 575	burst = 1;
 576
 577	if (mcspi->fifo_depth > 0) {
 578		if (count > mcspi->fifo_depth)
 579			burst = mcspi->fifo_depth / es;
 580		else
 581			burst = count / es;
 582	}
 583
 584	memset(&cfg, 0, sizeof(cfg));
 585	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 586	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 587	cfg.src_addr_width = width;
 588	cfg.dst_addr_width = width;
 589	cfg.src_maxburst = burst;
 590	cfg.dst_maxburst = burst;
 591
 592	rx = xfer->rx_buf;
 593	tx = xfer->tx_buf;
 594
 595	if (tx != NULL)
 
 
 
 
 
 
 
 
 
 596		omap2_mcspi_tx_dma(spi, xfer, cfg);
 
 597
 598	if (rx != NULL)
 599		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 600
 601	if (tx != NULL) {
 602		wait_for_completion(&mcspi_dma->dma_tx_completion);
 603		dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len,
 604				 DMA_TO_DEVICE);
 
 
 
 
 
 
 
 
 
 
 
 605
 606		if (mcspi->fifo_depth > 0) {
 607			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 608
 609			if (mcspi_wait_for_reg_bit(irqstat_reg,
 610						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 611				dev_err(&spi->dev, "EOW timed out\n");
 612
 613			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 614					OMAP2_MCSPI_IRQSTATUS_EOW);
 615		}
 616
 617		/* for TX_ONLY mode, be sure all words have shifted out */
 618		if (rx == NULL) {
 619			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 620			if (mcspi->fifo_depth > 0) {
 621				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 622						OMAP2_MCSPI_CHSTAT_TXFFE);
 623				if (wait_res < 0)
 624					dev_err(&spi->dev, "TXFFE timed out\n");
 625			} else {
 626				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 627						OMAP2_MCSPI_CHSTAT_TXS);
 628				if (wait_res < 0)
 629					dev_err(&spi->dev, "TXS timed out\n");
 630			}
 631			if (wait_res >= 0 &&
 632				(mcspi_wait_for_reg_bit(chstat_reg,
 633					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 634				dev_err(&spi->dev, "EOT timed out\n");
 635		}
 636	}
 637	return count;
 638}
 639
 640static unsigned
 641omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 642{
 643	struct omap2_mcspi	*mcspi;
 644	struct omap2_mcspi_cs	*cs = spi->controller_state;
 645	unsigned int		count, c;
 646	u32			l;
 647	void __iomem		*base = cs->base;
 648	void __iomem		*tx_reg;
 649	void __iomem		*rx_reg;
 650	void __iomem		*chstat_reg;
 651	int			word_len;
 652
 653	mcspi = spi_master_get_devdata(spi->master);
 654	count = xfer->len;
 655	c = count;
 656	word_len = cs->word_len;
 657
 658	l = mcspi_cached_chconf0(spi);
 659
 660	/* We store the pre-calculated register addresses on stack to speed
 661	 * up the transfer loop. */
 662	tx_reg		= base + OMAP2_MCSPI_TX0;
 663	rx_reg		= base + OMAP2_MCSPI_RX0;
 664	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 665
 666	if (c < (word_len>>3))
 667		return 0;
 668
 669	if (word_len <= 8) {
 670		u8		*rx;
 671		const u8	*tx;
 672
 673		rx = xfer->rx_buf;
 674		tx = xfer->tx_buf;
 675
 676		do {
 677			c -= 1;
 678			if (tx != NULL) {
 679				if (mcspi_wait_for_reg_bit(chstat_reg,
 680						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 681					dev_err(&spi->dev, "TXS timed out\n");
 682					goto out;
 683				}
 684				dev_vdbg(&spi->dev, "write-%d %02x\n",
 685						word_len, *tx);
 686				writel_relaxed(*tx++, tx_reg);
 687			}
 688			if (rx != NULL) {
 689				if (mcspi_wait_for_reg_bit(chstat_reg,
 690						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 691					dev_err(&spi->dev, "RXS timed out\n");
 692					goto out;
 693				}
 694
 695				if (c == 1 && tx == NULL &&
 696				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 697					omap2_mcspi_set_enable(spi, 0);
 698					*rx++ = readl_relaxed(rx_reg);
 699					dev_vdbg(&spi->dev, "read-%d %02x\n",
 700						    word_len, *(rx - 1));
 701					if (mcspi_wait_for_reg_bit(chstat_reg,
 702						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 703						dev_err(&spi->dev,
 704							"RXS timed out\n");
 705						goto out;
 706					}
 707					c = 0;
 708				} else if (c == 0 && tx == NULL) {
 709					omap2_mcspi_set_enable(spi, 0);
 710				}
 711
 712				*rx++ = readl_relaxed(rx_reg);
 713				dev_vdbg(&spi->dev, "read-%d %02x\n",
 714						word_len, *(rx - 1));
 715			}
 
 
 716		} while (c);
 717	} else if (word_len <= 16) {
 718		u16		*rx;
 719		const u16	*tx;
 720
 721		rx = xfer->rx_buf;
 722		tx = xfer->tx_buf;
 723		do {
 724			c -= 2;
 725			if (tx != NULL) {
 726				if (mcspi_wait_for_reg_bit(chstat_reg,
 727						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 728					dev_err(&spi->dev, "TXS timed out\n");
 729					goto out;
 730				}
 731				dev_vdbg(&spi->dev, "write-%d %04x\n",
 732						word_len, *tx);
 733				writel_relaxed(*tx++, tx_reg);
 734			}
 735			if (rx != NULL) {
 736				if (mcspi_wait_for_reg_bit(chstat_reg,
 737						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 738					dev_err(&spi->dev, "RXS timed out\n");
 739					goto out;
 740				}
 741
 742				if (c == 2 && tx == NULL &&
 743				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 744					omap2_mcspi_set_enable(spi, 0);
 745					*rx++ = readl_relaxed(rx_reg);
 746					dev_vdbg(&spi->dev, "read-%d %04x\n",
 747						    word_len, *(rx - 1));
 748					if (mcspi_wait_for_reg_bit(chstat_reg,
 749						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 750						dev_err(&spi->dev,
 751							"RXS timed out\n");
 752						goto out;
 753					}
 754					c = 0;
 755				} else if (c == 0 && tx == NULL) {
 756					omap2_mcspi_set_enable(spi, 0);
 757				}
 758
 759				*rx++ = readl_relaxed(rx_reg);
 760				dev_vdbg(&spi->dev, "read-%d %04x\n",
 761						word_len, *(rx - 1));
 762			}
 
 
 763		} while (c >= 2);
 764	} else if (word_len <= 32) {
 765		u32		*rx;
 766		const u32	*tx;
 767
 768		rx = xfer->rx_buf;
 769		tx = xfer->tx_buf;
 770		do {
 771			c -= 4;
 772			if (tx != NULL) {
 773				if (mcspi_wait_for_reg_bit(chstat_reg,
 774						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 775					dev_err(&spi->dev, "TXS timed out\n");
 776					goto out;
 777				}
 778				dev_vdbg(&spi->dev, "write-%d %08x\n",
 779						word_len, *tx);
 780				writel_relaxed(*tx++, tx_reg);
 781			}
 782			if (rx != NULL) {
 783				if (mcspi_wait_for_reg_bit(chstat_reg,
 784						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 785					dev_err(&spi->dev, "RXS timed out\n");
 786					goto out;
 787				}
 788
 789				if (c == 4 && tx == NULL &&
 790				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 791					omap2_mcspi_set_enable(spi, 0);
 792					*rx++ = readl_relaxed(rx_reg);
 793					dev_vdbg(&spi->dev, "read-%d %08x\n",
 794						    word_len, *(rx - 1));
 795					if (mcspi_wait_for_reg_bit(chstat_reg,
 796						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 797						dev_err(&spi->dev,
 798							"RXS timed out\n");
 799						goto out;
 800					}
 801					c = 0;
 802				} else if (c == 0 && tx == NULL) {
 803					omap2_mcspi_set_enable(spi, 0);
 804				}
 805
 806				*rx++ = readl_relaxed(rx_reg);
 807				dev_vdbg(&spi->dev, "read-%d %08x\n",
 808						word_len, *(rx - 1));
 809			}
 
 
 810		} while (c >= 4);
 811	}
 812
 813	/* for TX_ONLY mode, be sure all words have shifted out */
 814	if (xfer->rx_buf == NULL) {
 815		if (mcspi_wait_for_reg_bit(chstat_reg,
 816				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 817			dev_err(&spi->dev, "TXS timed out\n");
 818		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 819				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 820			dev_err(&spi->dev, "EOT timed out\n");
 821
 822		/* disable chan to purge rx datas received in TX_ONLY transfer,
 823		 * otherwise these rx datas will affect the direct following
 824		 * RX_ONLY transfer.
 825		 */
 826		omap2_mcspi_set_enable(spi, 0);
 827	}
 828out:
 829	omap2_mcspi_set_enable(spi, 1);
 830	return count - c;
 831}
 832
 833static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 834{
 835	u32 div;
 836
 837	for (div = 0; div < 15; div++)
 838		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 839			return div;
 840
 841	return 15;
 842}
 843
 844/* called only when no transfer is active to this device */
 845static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 846		struct spi_transfer *t)
 847{
 848	struct omap2_mcspi_cs *cs = spi->controller_state;
 849	struct omap2_mcspi *mcspi;
 850	struct spi_master *spi_cntrl;
 851	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 852	u8 word_len = spi->bits_per_word;
 853	u32 speed_hz = spi->max_speed_hz;
 854
 855	mcspi = spi_master_get_devdata(spi->master);
 856	spi_cntrl = mcspi->master;
 857
 858	if (t != NULL && t->bits_per_word)
 859		word_len = t->bits_per_word;
 860
 861	cs->word_len = word_len;
 862
 863	if (t && t->speed_hz)
 864		speed_hz = t->speed_hz;
 865
 866	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 867	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 868		clkd = omap2_mcspi_calc_divisor(speed_hz);
 869		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 
 870		clkg = 0;
 871	} else {
 872		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 873		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 874		clkd = (div - 1) & 0xf;
 875		extclk = (div - 1) >> 4;
 876		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 877	}
 878
 879	l = mcspi_cached_chconf0(spi);
 880
 881	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 882	 * REVISIT: this controller could support SPI_3WIRE mode.
 883	 */
 884	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 885		l &= ~OMAP2_MCSPI_CHCONF_IS;
 886		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 887		l |= OMAP2_MCSPI_CHCONF_DPE0;
 888	} else {
 889		l |= OMAP2_MCSPI_CHCONF_IS;
 890		l |= OMAP2_MCSPI_CHCONF_DPE1;
 891		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 892	}
 893
 894	/* wordlength */
 895	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 896	l |= (word_len - 1) << 7;
 897
 898	/* set chipselect polarity; manage with FORCE */
 899	if (!(spi->mode & SPI_CS_HIGH))
 900		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 901	else
 902		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 903
 904	/* set clock divisor */
 905	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 906	l |= clkd << 2;
 907
 908	/* set clock granularity */
 909	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 910	l |= clkg;
 911	if (clkg) {
 912		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 913		cs->chctrl0 |= extclk << 8;
 914		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 915	}
 916
 917	/* set SPI mode 0..3 */
 918	if (spi->mode & SPI_CPOL)
 919		l |= OMAP2_MCSPI_CHCONF_POL;
 920	else
 921		l &= ~OMAP2_MCSPI_CHCONF_POL;
 922	if (spi->mode & SPI_CPHA)
 923		l |= OMAP2_MCSPI_CHCONF_PHA;
 924	else
 925		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 926
 927	mcspi_write_chconf0(spi, l);
 928
 
 
 929	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 930			speed_hz,
 931			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 932			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 933
 934	return 0;
 935}
 936
 937/*
 938 * Note that we currently allow DMA only if we get a channel
 939 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 940 */
 941static int omap2_mcspi_request_dma(struct spi_device *spi)
 
 942{
 943	struct spi_master	*master = spi->master;
 944	struct omap2_mcspi	*mcspi;
 945	struct omap2_mcspi_dma	*mcspi_dma;
 946	dma_cap_mask_t mask;
 947	unsigned sig;
 
 
 
 
 948
 949	mcspi = spi_master_get_devdata(master);
 950	mcspi_dma = mcspi->dma_channels + spi->chip_select;
 
 
 
 
 
 
 951
 952	init_completion(&mcspi_dma->dma_rx_completion);
 953	init_completion(&mcspi_dma->dma_tx_completion);
 954
 955	dma_cap_zero(mask);
 956	dma_cap_set(DMA_SLAVE, mask);
 957	sig = mcspi_dma->dma_rx_sync_dev;
 958
 959	mcspi_dma->dma_rx =
 960		dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 961						 &sig, &master->dev,
 962						 mcspi_dma->dma_rx_ch_name);
 963	if (!mcspi_dma->dma_rx)
 964		goto no_dma;
 965
 966	sig = mcspi_dma->dma_tx_sync_dev;
 967	mcspi_dma->dma_tx =
 968		dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 969						 &sig, &master->dev,
 970						 mcspi_dma->dma_tx_ch_name);
 971
 972	if (!mcspi_dma->dma_tx) {
 973		dma_release_channel(mcspi_dma->dma_rx);
 974		mcspi_dma->dma_rx = NULL;
 975		goto no_dma;
 
 
 
 
 976	}
 
 
 
 
 
 977
 978	return 0;
 
 
 
 979
 980no_dma:
 981	dev_warn(&spi->dev, "not using DMA for McSPI\n");
 982	return -EAGAIN;
 983}
 984
 985static int omap2_mcspi_setup(struct spi_device *spi)
 986{
 
 987	int			ret;
 988	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
 989	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 990	struct omap2_mcspi_dma	*mcspi_dma;
 991	struct omap2_mcspi_cs	*cs = spi->controller_state;
 992
 993	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 994
 995	if (!cs) {
 996		cs = kzalloc(sizeof *cs, GFP_KERNEL);
 997		if (!cs)
 998			return -ENOMEM;
 999		cs->base = mcspi->base + spi->chip_select * 0x14;
1000		cs->phys = mcspi->phys + spi->chip_select * 0x14;
 
1001		cs->chconf0 = 0;
1002		cs->chctrl0 = 0;
1003		spi->controller_state = cs;
1004		/* Link this to context save list */
1005		list_add_tail(&cs->node, &ctx->cs);
 
1006	}
1007
1008	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1009		ret = omap2_mcspi_request_dma(spi);
1010		if (ret < 0 && ret != -EAGAIN)
1011			return ret;
1012	}
1013
1014	ret = pm_runtime_get_sync(mcspi->dev);
1015	if (ret < 0)
1016		return ret;
 
1017
1018	ret = omap2_mcspi_setup_transfer(spi, NULL);
 
 
 
1019	pm_runtime_mark_last_busy(mcspi->dev);
1020	pm_runtime_put_autosuspend(mcspi->dev);
1021
1022	return ret;
1023}
1024
1025static void omap2_mcspi_cleanup(struct spi_device *spi)
1026{
1027	struct omap2_mcspi	*mcspi;
1028	struct omap2_mcspi_dma	*mcspi_dma;
1029	struct omap2_mcspi_cs	*cs;
 
 
 
1030
1031	mcspi = spi_master_get_devdata(spi->master);
 
 
 
1032
1033	if (spi->controller_state) {
1034		/* Unlink controller state from context save list */
1035		cs = spi->controller_state;
1036		list_del(&cs->node);
1037
1038		kfree(cs);
1039	}
 
 
1040
1041	if (spi->chip_select < spi->master->num_chipselect) {
1042		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 
 
1043
1044		if (mcspi_dma->dma_rx) {
1045			dma_release_channel(mcspi_dma->dma_rx);
1046			mcspi_dma->dma_rx = NULL;
1047		}
1048		if (mcspi_dma->dma_tx) {
1049			dma_release_channel(mcspi_dma->dma_tx);
1050			mcspi_dma->dma_tx = NULL;
1051		}
1052	}
1053}
1054
1055static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
 
 
1056{
1057
1058	/* We only enable one channel at a time -- the one whose message is
1059	 * -- although this controller would gladly
1060	 * arbitrate among multiple channels.  This corresponds to "single
1061	 * channel" master mode.  As a side effect, we need to manage the
1062	 * chipselect with the FORCE bit ... CS != channel enable.
1063	 */
1064
1065	struct spi_device		*spi;
1066	struct spi_transfer		*t = NULL;
1067	struct spi_master		*master;
1068	struct omap2_mcspi_dma		*mcspi_dma;
1069	int				cs_active = 0;
1070	struct omap2_mcspi_cs		*cs;
1071	struct omap2_mcspi_device_config *cd;
1072	int				par_override = 0;
1073	int				status = 0;
1074	u32				chconf;
1075
1076	spi = m->spi;
1077	master = spi->master;
1078	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1079	cs = spi->controller_state;
1080	cd = spi->controller_data;
1081
 
 
 
 
 
 
 
 
 
 
1082	omap2_mcspi_set_enable(spi, 0);
1083	list_for_each_entry(t, &m->transfers, transfer_list) {
1084		if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
1085			status = -EINVAL;
1086			break;
1087		}
1088		if (par_override ||
1089		    (t->speed_hz != spi->max_speed_hz) ||
1090		    (t->bits_per_word != spi->bits_per_word)) {
1091			par_override = 1;
1092			status = omap2_mcspi_setup_transfer(spi, t);
1093			if (status < 0)
1094				break;
1095			if (t->speed_hz == spi->max_speed_hz &&
1096			    t->bits_per_word == spi->bits_per_word)
1097				par_override = 0;
1098		}
1099		if (cd && cd->cs_per_word) {
1100			chconf = mcspi->ctx.modulctrl;
1101			chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1102			mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1103			mcspi->ctx.modulctrl =
1104				mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1105		}
1106
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1107
1108		if (!cs_active) {
1109			omap2_mcspi_force_cs(spi, 1);
1110			cs_active = 1;
1111		}
1112
1113		chconf = mcspi_cached_chconf0(spi);
1114		chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1115		chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
 
 
 
 
 
 
 
1116
1117		if (t->tx_buf == NULL)
1118			chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1119		else if (t->rx_buf == NULL)
1120			chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1121
1122		if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1123			/* Turbo mode is for more than one word */
1124			if (t->len > ((cs->word_len + 7) >> 3))
1125				chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1126		}
1127
1128		mcspi_write_chconf0(spi, chconf);
 
1129
1130		if (t->len) {
1131			unsigned	count;
 
1132
1133			if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1134			    (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1135				omap2_mcspi_set_fifo(spi, t, 1);
1136
1137			omap2_mcspi_set_enable(spi, 1);
 
 
 
1138
1139			/* RX_ONLY mode needs dummy data in TX reg */
1140			if (t->tx_buf == NULL)
1141				writel_relaxed(0, cs->base
1142						+ OMAP2_MCSPI_TX0);
1143
1144			if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1145			    (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1146				count = omap2_mcspi_txrx_dma(spi, t);
1147			else
1148				count = omap2_mcspi_txrx_pio(spi, t);
1149			m->actual_length += count;
1150
1151			if (count != t->len) {
1152				status = -EIO;
1153				break;
1154			}
1155		}
 
1156
1157		if (t->delay_usecs)
1158			udelay(t->delay_usecs);
1159
1160		/* ignore the "leave it on after last xfer" hint */
1161		if (t->cs_change) {
1162			omap2_mcspi_force_cs(spi, 0);
1163			cs_active = 0;
1164		}
1165
1166		omap2_mcspi_set_enable(spi, 0);
1167
1168		if (mcspi->fifo_depth > 0)
1169			omap2_mcspi_set_fifo(spi, t, 0);
1170	}
1171	/* Restore defaults if they were overriden */
1172	if (par_override) {
1173		par_override = 0;
1174		status = omap2_mcspi_setup_transfer(spi, NULL);
1175	}
1176
1177	if (cs_active)
1178		omap2_mcspi_force_cs(spi, 0);
1179
1180	if (cd && cd->cs_per_word) {
1181		chconf = mcspi->ctx.modulctrl;
1182		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1183		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1184		mcspi->ctx.modulctrl =
1185			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1186	}
1187
1188	omap2_mcspi_set_enable(spi, 0);
1189
1190	if (mcspi->fifo_depth > 0 && t)
1191		omap2_mcspi_set_fifo(spi, t, 0);
1192
1193	m->status = status;
1194}
1195
1196static int omap2_mcspi_transfer_one_message(struct spi_master *master,
1197		struct spi_message *m)
1198{
1199	struct spi_device	*spi;
1200	struct omap2_mcspi	*mcspi;
1201	struct omap2_mcspi_dma	*mcspi_dma;
1202	struct spi_transfer	*t;
 
 
 
 
 
 
 
 
 
 
 
 
1203
1204	spi = m->spi;
1205	mcspi = spi_master_get_devdata(master);
1206	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1207	m->actual_length = 0;
1208	m->status = 0;
1209
1210	list_for_each_entry(t, &m->transfers, transfer_list) {
1211		const void	*tx_buf = t->tx_buf;
1212		void		*rx_buf = t->rx_buf;
1213		unsigned	len = t->len;
1214
1215		if ((len && !(rx_buf || tx_buf))) {
1216			dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1217					t->speed_hz,
1218					len,
1219					tx_buf ? "tx" : "",
1220					rx_buf ? "rx" : "",
1221					t->bits_per_word);
1222			return -EINVAL;
1223		}
1224
1225		if (m->is_dma_mapped || len < DMA_MIN_BYTES)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1226			continue;
 
1227
1228		if (mcspi_dma->dma_tx && tx_buf != NULL) {
1229			t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1230					len, DMA_TO_DEVICE);
1231			if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1232				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1233						'T', len);
1234				return -EINVAL;
1235			}
1236		}
1237		if (mcspi_dma->dma_rx && rx_buf != NULL) {
1238			t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1239					DMA_FROM_DEVICE);
1240			if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1241				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1242						'R', len);
1243				if (tx_buf != NULL)
1244					dma_unmap_single(mcspi->dev, t->tx_dma,
1245							len, DMA_TO_DEVICE);
1246				return -EINVAL;
1247			}
1248		}
1249	}
1250
1251	omap2_mcspi_work(mcspi, m);
1252	spi_finalize_current_message(master);
1253	return 0;
1254}
1255
1256static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1257{
1258	struct spi_master	*master = mcspi->master;
 
 
 
 
 
 
 
 
 
 
 
 
1259	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1260	int			ret = 0;
1261
1262	ret = pm_runtime_get_sync(mcspi->dev);
1263	if (ret < 0)
1264		return ret;
1265
1266	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1267			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1268	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1269
1270	omap2_mcspi_set_master_mode(master);
1271	pm_runtime_mark_last_busy(mcspi->dev);
1272	pm_runtime_put_autosuspend(mcspi->dev);
1273	return 0;
1274}
1275
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1276static int omap_mcspi_runtime_resume(struct device *dev)
1277{
1278	struct omap2_mcspi	*mcspi;
1279	struct spi_master	*master;
 
 
 
 
 
 
 
 
 
 
 
1280
1281	master = dev_get_drvdata(dev);
1282	mcspi = spi_master_get_devdata(master);
1283	omap2_mcspi_restore_ctx(mcspi);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1284
1285	return 0;
1286}
1287
1288static struct omap2_mcspi_platform_config omap2_pdata = {
1289	.regs_offset = 0,
1290};
1291
1292static struct omap2_mcspi_platform_config omap4_pdata = {
1293	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1294};
1295
 
 
 
 
 
1296static const struct of_device_id omap_mcspi_of_match[] = {
1297	{
1298		.compatible = "ti,omap2-mcspi",
1299		.data = &omap2_pdata,
1300	},
1301	{
1302		.compatible = "ti,omap4-mcspi",
1303		.data = &omap4_pdata,
1304	},
 
 
 
 
1305	{ },
1306};
1307MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1308
1309static int omap2_mcspi_probe(struct platform_device *pdev)
1310{
1311	struct spi_master	*master;
1312	const struct omap2_mcspi_platform_config *pdata;
1313	struct omap2_mcspi	*mcspi;
1314	struct resource		*r;
1315	int			status = 0, i;
1316	u32			regs_offset = 0;
1317	static int		bus_num = 1;
1318	struct device_node	*node = pdev->dev.of_node;
1319	const struct of_device_id *match;
1320
1321	master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1322	if (master == NULL) {
1323		dev_dbg(&pdev->dev, "master allocation failed\n");
 
 
1324		return -ENOMEM;
1325	}
1326
1327	/* the spi->mode bits understood by this driver: */
1328	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1329	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1330	master->setup = omap2_mcspi_setup;
1331	master->auto_runtime_pm = true;
1332	master->transfer_one_message = omap2_mcspi_transfer_one_message;
1333	master->cleanup = omap2_mcspi_cleanup;
1334	master->dev.of_node = node;
1335	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1336	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
 
 
 
1337
1338	platform_set_drvdata(pdev, master);
1339
1340	mcspi = spi_master_get_devdata(master);
1341	mcspi->master = master;
1342
1343	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1344	if (match) {
1345		u32 num_cs = 1; /* default number of chipselect */
1346		pdata = match->data;
1347
1348		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1349		master->num_chipselect = num_cs;
1350		master->bus_num = bus_num++;
1351		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1352			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1353	} else {
1354		pdata = dev_get_platdata(&pdev->dev);
1355		master->num_chipselect = pdata->num_cs;
1356		if (pdev->id != -1)
1357			master->bus_num = pdev->id;
1358		mcspi->pin_dir = pdata->pin_dir;
1359	}
1360	regs_offset = pdata->regs_offset;
1361
1362	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1363	if (r == NULL) {
1364		status = -ENODEV;
1365		goto free_master;
1366	}
1367
1368	r->start += regs_offset;
1369	r->end += regs_offset;
1370	mcspi->phys = r->start;
1371
1372	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1373	if (IS_ERR(mcspi->base)) {
1374		status = PTR_ERR(mcspi->base);
1375		goto free_master;
1376	}
 
 
1377
1378	mcspi->dev = &pdev->dev;
1379
1380	INIT_LIST_HEAD(&mcspi->ctx.cs);
1381
1382	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1383					   sizeof(struct omap2_mcspi_dma),
1384					   GFP_KERNEL);
1385	if (mcspi->dma_channels == NULL) {
1386		status = -ENOMEM;
1387		goto free_master;
1388	}
1389
1390	for (i = 0; i < master->num_chipselect; i++) {
1391		char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1392		char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1393		struct resource *dma_res;
1394
1395		sprintf(dma_rx_ch_name, "rx%d", i);
1396		if (!pdev->dev.of_node) {
1397			dma_res =
1398				platform_get_resource_byname(pdev,
1399							     IORESOURCE_DMA,
1400							     dma_rx_ch_name);
1401			if (!dma_res) {
1402				dev_dbg(&pdev->dev,
1403					"cannot get DMA RX channel\n");
1404				status = -ENODEV;
1405				break;
1406			}
1407
1408			mcspi->dma_channels[i].dma_rx_sync_dev =
1409				dma_res->start;
1410		}
1411		sprintf(dma_tx_ch_name, "tx%d", i);
1412		if (!pdev->dev.of_node) {
1413			dma_res =
1414				platform_get_resource_byname(pdev,
1415							     IORESOURCE_DMA,
1416							     dma_tx_ch_name);
1417			if (!dma_res) {
1418				dev_dbg(&pdev->dev,
1419					"cannot get DMA TX channel\n");
1420				status = -ENODEV;
1421				break;
1422			}
1423
1424			mcspi->dma_channels[i].dma_tx_sync_dev =
1425				dma_res->start;
1426		}
1427	}
1428
 
1429	if (status < 0)
1430		goto free_master;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1431
1432	pm_runtime_use_autosuspend(&pdev->dev);
1433	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1434	pm_runtime_enable(&pdev->dev);
1435
1436	status = omap2_mcspi_master_setup(mcspi);
1437	if (status < 0)
1438		goto disable_pm;
1439
1440	status = devm_spi_register_master(&pdev->dev, master);
1441	if (status < 0)
1442		goto disable_pm;
1443
1444	return status;
1445
1446disable_pm:
 
 
1447	pm_runtime_disable(&pdev->dev);
1448free_master:
1449	spi_master_put(master);
 
1450	return status;
1451}
1452
1453static int omap2_mcspi_remove(struct platform_device *pdev)
1454{
1455	struct spi_master *master = platform_get_drvdata(pdev);
1456	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 
 
1457
 
1458	pm_runtime_put_sync(mcspi->dev);
1459	pm_runtime_disable(&pdev->dev);
1460
1461	return 0;
1462}
1463
1464/* work with hotplug and coldplug */
1465MODULE_ALIAS("platform:omap2_mcspi");
1466
1467#ifdef	CONFIG_SUSPEND
1468/*
1469 * When SPI wake up from off-mode, CS is in activate state. If it was in
1470 * unactive state when driver was suspend, then force it to unactive state at
1471 * wake up.
1472 */
1473static int omap2_mcspi_resume(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
1474{
1475	struct spi_master	*master = dev_get_drvdata(dev);
1476	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1477	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1478	struct omap2_mcspi_cs	*cs;
 
 
 
 
1479
1480	pm_runtime_get_sync(mcspi->dev);
1481	list_for_each_entry(cs, &ctx->cs, node) {
1482		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1483			/*
1484			 * We need to toggle CS state for OMAP take this
1485			 * change in account.
1486			 */
1487			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1488			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1489			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1490			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1491		}
1492	}
1493	pm_runtime_mark_last_busy(mcspi->dev);
1494	pm_runtime_put_autosuspend(mcspi->dev);
1495	return 0;
1496}
1497#else
1498#define	omap2_mcspi_resume	NULL
1499#endif
1500
1501static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1502	.resume = omap2_mcspi_resume,
1503	.runtime_resume	= omap_mcspi_runtime_resume,
 
 
1504};
1505
1506static struct platform_driver omap2_mcspi_driver = {
1507	.driver = {
1508		.name =		"omap2_mcspi",
1509		.owner =	THIS_MODULE,
1510		.pm =		&omap2_mcspi_pm_ops,
1511		.of_match_table = omap_mcspi_of_match,
1512	},
1513	.probe =	omap2_mcspi_probe,
1514	.remove =	omap2_mcspi_remove,
1515};
1516
1517module_platform_driver(omap2_mcspi_driver);
 
1518MODULE_LICENSE("GPL");