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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");
v5.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * OMAP2 McSPI controller driver
   4 *
   5 * Copyright (C) 2005, 2006 Nokia Corporation
   6 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   7 *		Juha Yrj�l� <juha.yrjola@nokia.com>
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/interrupt.h>
  12#include <linux/module.h>
  13#include <linux/device.h>
  14#include <linux/delay.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/dmaengine.h>
  17#include <linux/pinctrl/consumer.h>
  18#include <linux/platform_device.h>
  19#include <linux/err.h>
  20#include <linux/clk.h>
  21#include <linux/io.h>
  22#include <linux/slab.h>
  23#include <linux/pm_runtime.h>
  24#include <linux/of.h>
  25#include <linux/of_device.h>
  26#include <linux/gcd.h>
  27#include <linux/iopoll.h>
  28
  29#include <linux/spi/spi.h>
  30#include <linux/gpio.h>
 
  31
  32#include <linux/platform_data/spi-omap2-mcspi.h>
  33
  34#define OMAP2_MCSPI_MAX_FREQ		48000000
  35#define OMAP2_MCSPI_MAX_DIVIDER		4096
  36#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  37#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  38#define SPI_AUTOSUSPEND_TIMEOUT		2000
  39
  40#define OMAP2_MCSPI_REVISION		0x00
  41#define OMAP2_MCSPI_SYSSTATUS		0x14
  42#define OMAP2_MCSPI_IRQSTATUS		0x18
  43#define OMAP2_MCSPI_IRQENABLE		0x1c
  44#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  45#define OMAP2_MCSPI_SYST		0x24
  46#define OMAP2_MCSPI_MODULCTRL		0x28
  47#define OMAP2_MCSPI_XFERLEVEL		0x7c
  48
  49/* per-channel banks, 0x14 bytes each, first is: */
  50#define OMAP2_MCSPI_CHCONF0		0x2c
  51#define OMAP2_MCSPI_CHSTAT0		0x30
  52#define OMAP2_MCSPI_CHCTRL0		0x34
  53#define OMAP2_MCSPI_TX0			0x38
  54#define OMAP2_MCSPI_RX0			0x3c
  55
  56/* per-register bitmasks: */
  57#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  58
  59#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  60#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  61#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  62
  63#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  64#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  65#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  66#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  67#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  68#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  69#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  70#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  71#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  72#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  73#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  74#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  75#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  76#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  77#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  78#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  79#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  80#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  81
  82#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  83#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  84#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  85#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  86
  87#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
  88#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
  89
  90#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  91
  92/* We have 2 DMA channels per CS, one for RX and one for TX */
  93struct omap2_mcspi_dma {
  94	struct dma_chan *dma_tx;
  95	struct dma_chan *dma_rx;
  96
  97	struct completion dma_tx_completion;
  98	struct completion dma_rx_completion;
  99
 100	char dma_rx_ch_name[14];
 101	char dma_tx_ch_name[14];
 102};
 103
 104/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 105 * cache operations; better heuristics consider wordsize and bitrate.
 106 */
 107#define DMA_MIN_BYTES			160
 108
 109
 110/*
 111 * Used for context save and restore, structure members to be updated whenever
 112 * corresponding registers are modified.
 113 */
 114struct omap2_mcspi_regs {
 115	u32 modulctrl;
 116	u32 wakeupenable;
 117	struct list_head cs;
 118};
 119
 120struct omap2_mcspi {
 121	struct completion	txdone;
 122	struct spi_master	*master;
 123	/* Virtual base address of the controller */
 124	void __iomem		*base;
 125	unsigned long		phys;
 126	/* SPI1 has 4 channels, while SPI2 has 2 */
 127	struct omap2_mcspi_dma	*dma_channels;
 128	struct device		*dev;
 129	struct omap2_mcspi_regs ctx;
 
 130	int			fifo_depth;
 131	bool			slave_aborted;
 132	unsigned int		pin_dir:1;
 
 
 
 133};
 134
 135struct omap2_mcspi_cs {
 136	void __iomem		*base;
 137	unsigned long		phys;
 138	int			word_len;
 139	u16			mode;
 140	struct list_head	node;
 141	/* Context save and restore shadow register */
 142	u32			chconf0, chctrl0;
 143};
 144
 145static inline void mcspi_write_reg(struct spi_master *master,
 146		int idx, u32 val)
 147{
 148	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 149
 150	writel_relaxed(val, mcspi->base + idx);
 151}
 152
 153static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 154{
 155	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 156
 157	return readl_relaxed(mcspi->base + idx);
 158}
 159
 160static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 161		int idx, u32 val)
 162{
 163	struct omap2_mcspi_cs	*cs = spi->controller_state;
 164
 165	writel_relaxed(val, cs->base +  idx);
 166}
 167
 168static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 169{
 170	struct omap2_mcspi_cs	*cs = spi->controller_state;
 171
 172	return readl_relaxed(cs->base + idx);
 173}
 174
 175static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 176{
 177	struct omap2_mcspi_cs *cs = spi->controller_state;
 178
 179	return cs->chconf0;
 180}
 181
 182static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 183{
 184	struct omap2_mcspi_cs *cs = spi->controller_state;
 185
 186	cs->chconf0 = val;
 187	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 188	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 189}
 190
 191static inline int mcspi_bytes_per_word(int word_len)
 192{
 193	if (word_len <= 8)
 194		return 1;
 195	else if (word_len <= 16)
 196		return 2;
 197	else /* word_len <= 32 */
 198		return 4;
 199}
 200
 201static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 202		int is_read, int enable)
 203{
 204	u32 l, rw;
 205
 206	l = mcspi_cached_chconf0(spi);
 207
 208	if (is_read) /* 1 is read, 0 write */
 209		rw = OMAP2_MCSPI_CHCONF_DMAR;
 210	else
 211		rw = OMAP2_MCSPI_CHCONF_DMAW;
 212
 213	if (enable)
 214		l |= rw;
 215	else
 216		l &= ~rw;
 217
 218	mcspi_write_chconf0(spi, l);
 219}
 220
 221static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 222{
 223	struct omap2_mcspi_cs *cs = spi->controller_state;
 224	u32 l;
 225
 226	l = cs->chctrl0;
 227	if (enable)
 228		l |= OMAP2_MCSPI_CHCTRL_EN;
 229	else
 230		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 231	cs->chctrl0 = l;
 232	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 233	/* Flash post-writes */
 234	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 235}
 236
 237static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 238{
 239	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 240	u32 l;
 241
 242	/* The controller handles the inverted chip selects
 243	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 244	 * the inversion from the core spi_set_cs function.
 245	 */
 246	if (spi->mode & SPI_CS_HIGH)
 247		enable = !enable;
 248
 249	if (spi->controller_state) {
 250		int err = pm_runtime_get_sync(mcspi->dev);
 251		if (err < 0) {
 252			pm_runtime_put_noidle(mcspi->dev);
 253			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 254			return;
 255		}
 256
 257		l = mcspi_cached_chconf0(spi);
 258
 259		if (enable)
 
 260			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 261		else
 262			l |= OMAP2_MCSPI_CHCONF_FORCE;
 
 
 
 
 263
 264		mcspi_write_chconf0(spi, l);
 265
 266		pm_runtime_mark_last_busy(mcspi->dev);
 267		pm_runtime_put_autosuspend(mcspi->dev);
 268	}
 269}
 270
 271static void omap2_mcspi_set_mode(struct spi_master *master)
 272{
 273	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 274	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 275	u32 l;
 276
 277	/*
 278	 * Choose master or slave mode
 279	 */
 280	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 281	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
 282	if (spi_controller_is_slave(master)) {
 283		l |= (OMAP2_MCSPI_MODULCTRL_MS);
 284	} else {
 285		l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
 286		l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 
 
 
 
 
 287	}
 288	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 289
 290	ctx->modulctrl = l;
 291}
 292
 293static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 294				struct spi_transfer *t, int enable)
 295{
 296	struct spi_master *master = spi->master;
 297	struct omap2_mcspi_cs *cs = spi->controller_state;
 298	struct omap2_mcspi *mcspi;
 299	unsigned int wcnt;
 300	int max_fifo_depth, bytes_per_word;
 301	u32 chconf, xferlevel;
 302
 303	mcspi = spi_master_get_devdata(master);
 304
 305	chconf = mcspi_cached_chconf0(spi);
 306	if (enable) {
 307		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 308		if (t->len % bytes_per_word != 0)
 309			goto disable_fifo;
 310
 311		if (t->rx_buf != NULL && t->tx_buf != NULL)
 312			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 313		else
 314			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 315
 316		wcnt = t->len / bytes_per_word;
 317		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 318			goto disable_fifo;
 319
 320		xferlevel = wcnt << 16;
 321		if (t->rx_buf != NULL) {
 322			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 323			xferlevel |= (bytes_per_word - 1) << 8;
 324		}
 325
 326		if (t->tx_buf != NULL) {
 327			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 328			xferlevel |= bytes_per_word - 1;
 329		}
 330
 331		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 332		mcspi_write_chconf0(spi, chconf);
 333		mcspi->fifo_depth = max_fifo_depth;
 334
 335		return;
 336	}
 337
 338disable_fifo:
 339	if (t->rx_buf != NULL)
 340		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 341
 342	if (t->tx_buf != NULL)
 343		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 344
 345	mcspi_write_chconf0(spi, chconf);
 346	mcspi->fifo_depth = 0;
 347}
 348
 349static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 350{
 351	u32 val;
 352
 353	return readl_poll_timeout(reg, val, val & bit, 1, MSEC_PER_SEC);
 
 
 
 
 
 
 
 
 
 
 354}
 355
 356static int mcspi_wait_for_completion(struct  omap2_mcspi *mcspi,
 357				     struct completion *x)
 358{
 359	if (spi_controller_is_slave(mcspi->master)) {
 360		if (wait_for_completion_interruptible(x) ||
 361		    mcspi->slave_aborted)
 362			return -EINTR;
 363	} else {
 364		wait_for_completion(x);
 365	}
 366
 367	return 0;
 368}
 369
 370static void omap2_mcspi_rx_callback(void *data)
 371{
 372	struct spi_device *spi = data;
 373	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 374	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 375
 376	/* We must disable the DMA RX request */
 377	omap2_mcspi_set_dma_req(spi, 1, 0);
 378
 379	complete(&mcspi_dma->dma_rx_completion);
 380}
 381
 382static void omap2_mcspi_tx_callback(void *data)
 383{
 384	struct spi_device *spi = data;
 385	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 386	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 387
 388	/* We must disable the DMA TX request */
 389	omap2_mcspi_set_dma_req(spi, 0, 0);
 390
 391	complete(&mcspi_dma->dma_tx_completion);
 392}
 393
 394static void omap2_mcspi_tx_dma(struct spi_device *spi,
 395				struct spi_transfer *xfer,
 396				struct dma_slave_config cfg)
 397{
 398	struct omap2_mcspi	*mcspi;
 399	struct omap2_mcspi_dma  *mcspi_dma;
 
 400
 401	mcspi = spi_master_get_devdata(spi->master);
 402	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 403
 404	if (mcspi_dma->dma_tx) {
 405		struct dma_async_tx_descriptor *tx;
 406
 407		dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 408
 409		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 410					     xfer->tx_sg.nents,
 411					     DMA_MEM_TO_DEV,
 412					     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 413		if (tx) {
 414			tx->callback = omap2_mcspi_tx_callback;
 415			tx->callback_param = spi;
 416			dmaengine_submit(tx);
 417		} else {
 418			/* FIXME: fall back to PIO? */
 419		}
 420	}
 421	dma_async_issue_pending(mcspi_dma->dma_tx);
 422	omap2_mcspi_set_dma_req(spi, 0, 1);
 423
 424}
 425
 426static unsigned
 427omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 428				struct dma_slave_config cfg,
 429				unsigned es)
 430{
 431	struct omap2_mcspi	*mcspi;
 432	struct omap2_mcspi_dma  *mcspi_dma;
 433	unsigned int		count, transfer_reduction = 0;
 434	struct scatterlist	*sg_out[2];
 435	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 436	size_t			sizes[2];
 437	u32			l;
 438	int			elements = 0;
 439	int			word_len, element_count;
 440	struct omap2_mcspi_cs	*cs = spi->controller_state;
 441	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 
 442
 443	mcspi = spi_master_get_devdata(spi->master);
 444	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 445	count = xfer->len;
 446
 447	/*
 448	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 449	 *  it mentions reducing DMA transfer length by one element in master
 450	 *  normal mode.
 451	 */
 452	if (mcspi->fifo_depth == 0)
 453		transfer_reduction = es;
 454
 455	word_len = cs->word_len;
 456	l = mcspi_cached_chconf0(spi);
 457
 458	if (word_len <= 8)
 459		element_count = count;
 460	else if (word_len <= 16)
 461		element_count = count >> 1;
 462	else /* word_len <= 32 */
 463		element_count = count >> 2;
 464
 465	if (mcspi_dma->dma_rx) {
 466		struct dma_async_tx_descriptor *tx;
 467
 468		dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 469
 
 
 
 
 
 
 
 
 
 
 
 
 
 470		/*
 471		 *  Reduce DMA transfer length by one more if McSPI is
 472		 *  configured in turbo mode.
 473		 */
 474		if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 475			transfer_reduction += es;
 
 476
 477		if (transfer_reduction) {
 478			/* Split sgl into two. The second sgl won't be used. */
 479			sizes[0] = count - transfer_reduction;
 480			sizes[1] = transfer_reduction;
 481			nb_sizes = 2;
 482		} else {
 483			/*
 484			 * Don't bother splitting the sgl. This essentially
 485			 * clones the original sgl.
 486			 */
 487			sizes[0] = count;
 488			nb_sizes = 1;
 489		}
 490
 491		ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents,
 492			       0, nb_sizes,
 493			       sizes,
 494			       sg_out, out_mapped_nents,
 495			       GFP_KERNEL);
 496
 497		if (ret < 0) {
 498			dev_err(&spi->dev, "sg_split failed\n");
 499			return 0;
 500		}
 501
 502		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx,
 503					     sg_out[0],
 504					     out_mapped_nents[0],
 505					     DMA_DEV_TO_MEM,
 506					     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 507		if (tx) {
 508			tx->callback = omap2_mcspi_rx_callback;
 509			tx->callback_param = spi;
 510			dmaengine_submit(tx);
 511		} else {
 512				/* FIXME: fall back to PIO? */
 513		}
 514	}
 515
 516	dma_async_issue_pending(mcspi_dma->dma_rx);
 517	omap2_mcspi_set_dma_req(spi, 1, 1);
 518
 519	ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
 520	if (ret || mcspi->slave_aborted) {
 521		dmaengine_terminate_sync(mcspi_dma->dma_rx);
 522		omap2_mcspi_set_dma_req(spi, 1, 0);
 523		return 0;
 524	}
 525
 526	for (x = 0; x < nb_sizes; x++)
 527		kfree(sg_out[x]);
 528
 529	if (mcspi->fifo_depth > 0)
 530		return count;
 531
 532	/*
 533	 *  Due to the DMA transfer length reduction the missing bytes must
 534	 *  be read manually to receive all of the expected data.
 535	 */
 536	omap2_mcspi_set_enable(spi, 0);
 537
 538	elements = element_count - 1;
 539
 540	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 541		elements--;
 542
 543		if (!mcspi_wait_for_reg_bit(chstat_reg,
 544					    OMAP2_MCSPI_CHSTAT_RXS)) {
 545			u32 w;
 546
 547			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 548			if (word_len <= 8)
 549				((u8 *)xfer->rx_buf)[elements++] = w;
 550			else if (word_len <= 16)
 551				((u16 *)xfer->rx_buf)[elements++] = w;
 552			else /* word_len <= 32 */
 553				((u32 *)xfer->rx_buf)[elements++] = w;
 554		} else {
 555			int bytes_per_word = mcspi_bytes_per_word(word_len);
 556			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 557			count -= (bytes_per_word << 1);
 558			omap2_mcspi_set_enable(spi, 1);
 559			return count;
 560		}
 561	}
 562	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 563		u32 w;
 564
 565		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 566		if (word_len <= 8)
 567			((u8 *)xfer->rx_buf)[elements] = w;
 568		else if (word_len <= 16)
 569			((u16 *)xfer->rx_buf)[elements] = w;
 570		else /* word_len <= 32 */
 571			((u32 *)xfer->rx_buf)[elements] = w;
 572	} else {
 573		dev_err(&spi->dev, "DMA RX last word empty\n");
 574		count -= mcspi_bytes_per_word(word_len);
 575	}
 576	omap2_mcspi_set_enable(spi, 1);
 577	return count;
 578}
 579
 580static unsigned
 581omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 582{
 583	struct omap2_mcspi	*mcspi;
 584	struct omap2_mcspi_cs	*cs = spi->controller_state;
 585	struct omap2_mcspi_dma  *mcspi_dma;
 586	unsigned int		count;
 587	u8			*rx;
 588	const u8		*tx;
 589	struct dma_slave_config	cfg;
 590	enum dma_slave_buswidth width;
 591	unsigned es;
 592	void __iomem		*chstat_reg;
 593	void __iomem            *irqstat_reg;
 594	int			wait_res;
 595
 596	mcspi = spi_master_get_devdata(spi->master);
 597	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 598
 599	if (cs->word_len <= 8) {
 600		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 601		es = 1;
 602	} else if (cs->word_len <= 16) {
 603		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 604		es = 2;
 605	} else {
 606		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 607		es = 4;
 608	}
 609
 610	count = xfer->len;
 611
 612	memset(&cfg, 0, sizeof(cfg));
 613	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 614	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 615	cfg.src_addr_width = width;
 616	cfg.dst_addr_width = width;
 617	cfg.src_maxburst = 1;
 618	cfg.dst_maxburst = 1;
 619
 620	rx = xfer->rx_buf;
 621	tx = xfer->tx_buf;
 622
 623	mcspi->slave_aborted = false;
 624	reinit_completion(&mcspi_dma->dma_tx_completion);
 625	reinit_completion(&mcspi_dma->dma_rx_completion);
 626	reinit_completion(&mcspi->txdone);
 627	if (tx) {
 628		/* Enable EOW IRQ to know end of tx in slave mode */
 629		if (spi_controller_is_slave(spi->master))
 630			mcspi_write_reg(spi->master,
 631					OMAP2_MCSPI_IRQENABLE,
 632					OMAP2_MCSPI_IRQSTATUS_EOW);
 633		omap2_mcspi_tx_dma(spi, xfer, cfg);
 634	}
 635
 636	if (rx != NULL)
 637		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 638
 639	if (tx != NULL) {
 640		int ret;
 641
 642		ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
 643		if (ret || mcspi->slave_aborted) {
 644			dmaengine_terminate_sync(mcspi_dma->dma_tx);
 645			omap2_mcspi_set_dma_req(spi, 0, 0);
 646			return 0;
 647		}
 648
 649		if (spi_controller_is_slave(mcspi->master)) {
 650			ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
 651			if (ret || mcspi->slave_aborted)
 652				return 0;
 653		}
 654
 655		if (mcspi->fifo_depth > 0) {
 656			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 657
 658			if (mcspi_wait_for_reg_bit(irqstat_reg,
 659						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 660				dev_err(&spi->dev, "EOW timed out\n");
 661
 662			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 663					OMAP2_MCSPI_IRQSTATUS_EOW);
 664		}
 665
 666		/* for TX_ONLY mode, be sure all words have shifted out */
 667		if (rx == NULL) {
 668			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 669			if (mcspi->fifo_depth > 0) {
 670				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 671						OMAP2_MCSPI_CHSTAT_TXFFE);
 672				if (wait_res < 0)
 673					dev_err(&spi->dev, "TXFFE timed out\n");
 674			} else {
 675				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 676						OMAP2_MCSPI_CHSTAT_TXS);
 677				if (wait_res < 0)
 678					dev_err(&spi->dev, "TXS timed out\n");
 679			}
 680			if (wait_res >= 0 &&
 681				(mcspi_wait_for_reg_bit(chstat_reg,
 682					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 683				dev_err(&spi->dev, "EOT timed out\n");
 684		}
 685	}
 686	return count;
 687}
 688
 689static unsigned
 690omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 691{
 692	struct omap2_mcspi_cs	*cs = spi->controller_state;
 693	unsigned int		count, c;
 694	u32			l;
 695	void __iomem		*base = cs->base;
 696	void __iomem		*tx_reg;
 697	void __iomem		*rx_reg;
 698	void __iomem		*chstat_reg;
 699	int			word_len;
 700
 701	count = xfer->len;
 702	c = count;
 703	word_len = cs->word_len;
 704
 705	l = mcspi_cached_chconf0(spi);
 706
 707	/* We store the pre-calculated register addresses on stack to speed
 708	 * up the transfer loop. */
 709	tx_reg		= base + OMAP2_MCSPI_TX0;
 710	rx_reg		= base + OMAP2_MCSPI_RX0;
 711	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 712
 713	if (c < (word_len>>3))
 714		return 0;
 715
 716	if (word_len <= 8) {
 717		u8		*rx;
 718		const u8	*tx;
 719
 720		rx = xfer->rx_buf;
 721		tx = xfer->tx_buf;
 722
 723		do {
 724			c -= 1;
 725			if (tx != NULL) {
 726				if (mcspi_wait_for_reg_bit(chstat_reg,
 727						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 728					dev_err(&spi->dev, "TXS timed out\n");
 729					goto out;
 730				}
 731				dev_vdbg(&spi->dev, "write-%d %02x\n",
 732						word_len, *tx);
 733				writel_relaxed(*tx++, tx_reg);
 734			}
 735			if (rx != NULL) {
 736				if (mcspi_wait_for_reg_bit(chstat_reg,
 737						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 738					dev_err(&spi->dev, "RXS timed out\n");
 739					goto out;
 740				}
 741
 742				if (c == 1 && tx == NULL &&
 743				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 744					omap2_mcspi_set_enable(spi, 0);
 745					*rx++ = readl_relaxed(rx_reg);
 746					dev_vdbg(&spi->dev, "read-%d %02x\n",
 747						    word_len, *(rx - 1));
 748					if (mcspi_wait_for_reg_bit(chstat_reg,
 749						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 750						dev_err(&spi->dev,
 751							"RXS timed out\n");
 752						goto out;
 753					}
 754					c = 0;
 755				} else if (c == 0 && tx == NULL) {
 756					omap2_mcspi_set_enable(spi, 0);
 757				}
 758
 759				*rx++ = readl_relaxed(rx_reg);
 760				dev_vdbg(&spi->dev, "read-%d %02x\n",
 761						word_len, *(rx - 1));
 762			}
 
 
 763		} while (c);
 764	} else if (word_len <= 16) {
 765		u16		*rx;
 766		const u16	*tx;
 767
 768		rx = xfer->rx_buf;
 769		tx = xfer->tx_buf;
 770		do {
 771			c -= 2;
 772			if (tx != NULL) {
 773				if (mcspi_wait_for_reg_bit(chstat_reg,
 774						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 775					dev_err(&spi->dev, "TXS timed out\n");
 776					goto out;
 777				}
 778				dev_vdbg(&spi->dev, "write-%d %04x\n",
 779						word_len, *tx);
 780				writel_relaxed(*tx++, tx_reg);
 781			}
 782			if (rx != NULL) {
 783				if (mcspi_wait_for_reg_bit(chstat_reg,
 784						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 785					dev_err(&spi->dev, "RXS timed out\n");
 786					goto out;
 787				}
 788
 789				if (c == 2 && tx == NULL &&
 790				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 791					omap2_mcspi_set_enable(spi, 0);
 792					*rx++ = readl_relaxed(rx_reg);
 793					dev_vdbg(&spi->dev, "read-%d %04x\n",
 794						    word_len, *(rx - 1));
 795					if (mcspi_wait_for_reg_bit(chstat_reg,
 796						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 797						dev_err(&spi->dev,
 798							"RXS timed out\n");
 799						goto out;
 800					}
 801					c = 0;
 802				} else if (c == 0 && tx == NULL) {
 803					omap2_mcspi_set_enable(spi, 0);
 804				}
 805
 806				*rx++ = readl_relaxed(rx_reg);
 807				dev_vdbg(&spi->dev, "read-%d %04x\n",
 808						word_len, *(rx - 1));
 809			}
 
 
 810		} while (c >= 2);
 811	} else if (word_len <= 32) {
 812		u32		*rx;
 813		const u32	*tx;
 814
 815		rx = xfer->rx_buf;
 816		tx = xfer->tx_buf;
 817		do {
 818			c -= 4;
 819			if (tx != NULL) {
 820				if (mcspi_wait_for_reg_bit(chstat_reg,
 821						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 822					dev_err(&spi->dev, "TXS timed out\n");
 823					goto out;
 824				}
 825				dev_vdbg(&spi->dev, "write-%d %08x\n",
 826						word_len, *tx);
 827				writel_relaxed(*tx++, tx_reg);
 828			}
 829			if (rx != NULL) {
 830				if (mcspi_wait_for_reg_bit(chstat_reg,
 831						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 832					dev_err(&spi->dev, "RXS timed out\n");
 833					goto out;
 834				}
 835
 836				if (c == 4 && tx == NULL &&
 837				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 838					omap2_mcspi_set_enable(spi, 0);
 839					*rx++ = readl_relaxed(rx_reg);
 840					dev_vdbg(&spi->dev, "read-%d %08x\n",
 841						    word_len, *(rx - 1));
 842					if (mcspi_wait_for_reg_bit(chstat_reg,
 843						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 844						dev_err(&spi->dev,
 845							"RXS timed out\n");
 846						goto out;
 847					}
 848					c = 0;
 849				} else if (c == 0 && tx == NULL) {
 850					omap2_mcspi_set_enable(spi, 0);
 851				}
 852
 853				*rx++ = readl_relaxed(rx_reg);
 854				dev_vdbg(&spi->dev, "read-%d %08x\n",
 855						word_len, *(rx - 1));
 856			}
 
 
 857		} while (c >= 4);
 858	}
 859
 860	/* for TX_ONLY mode, be sure all words have shifted out */
 861	if (xfer->rx_buf == NULL) {
 862		if (mcspi_wait_for_reg_bit(chstat_reg,
 863				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 864			dev_err(&spi->dev, "TXS timed out\n");
 865		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 866				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 867			dev_err(&spi->dev, "EOT timed out\n");
 868
 869		/* disable chan to purge rx datas received in TX_ONLY transfer,
 870		 * otherwise these rx datas will affect the direct following
 871		 * RX_ONLY transfer.
 872		 */
 873		omap2_mcspi_set_enable(spi, 0);
 874	}
 875out:
 876	omap2_mcspi_set_enable(spi, 1);
 877	return count - c;
 878}
 879
 880static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 881{
 882	u32 div;
 883
 884	for (div = 0; div < 15; div++)
 885		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 886			return div;
 887
 888	return 15;
 889}
 890
 891/* called only when no transfer is active to this device */
 892static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 893		struct spi_transfer *t)
 894{
 895	struct omap2_mcspi_cs *cs = spi->controller_state;
 896	struct omap2_mcspi *mcspi;
 897	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 898	u8 word_len = spi->bits_per_word;
 899	u32 speed_hz = spi->max_speed_hz;
 900
 901	mcspi = spi_master_get_devdata(spi->master);
 902
 903	if (t != NULL && t->bits_per_word)
 904		word_len = t->bits_per_word;
 905
 906	cs->word_len = word_len;
 907
 908	if (t && t->speed_hz)
 909		speed_hz = t->speed_hz;
 910
 911	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 912	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 913		clkd = omap2_mcspi_calc_divisor(speed_hz);
 914		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 
 915		clkg = 0;
 916	} else {
 917		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 918		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 919		clkd = (div - 1) & 0xf;
 920		extclk = (div - 1) >> 4;
 921		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 922	}
 923
 924	l = mcspi_cached_chconf0(spi);
 925
 926	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 927	 * REVISIT: this controller could support SPI_3WIRE mode.
 928	 */
 929	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 930		l &= ~OMAP2_MCSPI_CHCONF_IS;
 931		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 932		l |= OMAP2_MCSPI_CHCONF_DPE0;
 933	} else {
 934		l |= OMAP2_MCSPI_CHCONF_IS;
 935		l |= OMAP2_MCSPI_CHCONF_DPE1;
 936		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 937	}
 938
 939	/* wordlength */
 940	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 941	l |= (word_len - 1) << 7;
 942
 943	/* set chipselect polarity; manage with FORCE */
 944	if (!(spi->mode & SPI_CS_HIGH))
 945		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 946	else
 947		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 948
 949	/* set clock divisor */
 950	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 951	l |= clkd << 2;
 952
 953	/* set clock granularity */
 954	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 955	l |= clkg;
 956	if (clkg) {
 957		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 958		cs->chctrl0 |= extclk << 8;
 959		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 960	}
 961
 962	/* set SPI mode 0..3 */
 963	if (spi->mode & SPI_CPOL)
 964		l |= OMAP2_MCSPI_CHCONF_POL;
 965	else
 966		l &= ~OMAP2_MCSPI_CHCONF_POL;
 967	if (spi->mode & SPI_CPHA)
 968		l |= OMAP2_MCSPI_CHCONF_PHA;
 969	else
 970		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 971
 972	mcspi_write_chconf0(spi, l);
 973
 974	cs->mode = spi->mode;
 975
 976	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 977			speed_hz,
 978			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 979			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 980
 981	return 0;
 982}
 983
 984/*
 985 * Note that we currently allow DMA only if we get a channel
 986 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 987 */
 988static int omap2_mcspi_request_dma(struct spi_device *spi)
 
 989{
 990	struct spi_master	*master = spi->master;
 991	struct omap2_mcspi	*mcspi;
 992	struct omap2_mcspi_dma	*mcspi_dma;
 993	int ret = 0;
 994
 995	mcspi = spi_master_get_devdata(master);
 996	mcspi_dma = mcspi->dma_channels + spi->chip_select;
 997
 998	init_completion(&mcspi_dma->dma_rx_completion);
 999	init_completion(&mcspi_dma->dma_tx_completion);
1000
1001	mcspi_dma->dma_rx = dma_request_chan(&master->dev,
1002					     mcspi_dma->dma_rx_ch_name);
1003	if (IS_ERR(mcspi_dma->dma_rx)) {
1004		ret = PTR_ERR(mcspi_dma->dma_rx);
1005		mcspi_dma->dma_rx = NULL;
1006		goto no_dma;
1007	}
1008
1009	mcspi_dma->dma_tx = dma_request_chan(&master->dev,
1010					     mcspi_dma->dma_tx_ch_name);
1011	if (IS_ERR(mcspi_dma->dma_tx)) {
1012		ret = PTR_ERR(mcspi_dma->dma_tx);
1013		mcspi_dma->dma_tx = NULL;
1014		dma_release_channel(mcspi_dma->dma_rx);
1015		mcspi_dma->dma_rx = NULL;
1016	}
1017
 
 
 
1018no_dma:
1019	return ret;
1020}
1021
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1022static int omap2_mcspi_setup(struct spi_device *spi)
1023{
 
1024	int			ret;
1025	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
1026	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1027	struct omap2_mcspi_dma	*mcspi_dma;
1028	struct omap2_mcspi_cs	*cs = spi->controller_state;
1029
1030	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1031
1032	if (!cs) {
1033		cs = kzalloc(sizeof *cs, GFP_KERNEL);
1034		if (!cs)
1035			return -ENOMEM;
1036		cs->base = mcspi->base + spi->chip_select * 0x14;
1037		cs->phys = mcspi->phys + spi->chip_select * 0x14;
1038		cs->mode = 0;
1039		cs->chconf0 = 0;
1040		cs->chctrl0 = 0;
1041		spi->controller_state = cs;
1042		/* Link this to context save list */
1043		list_add_tail(&cs->node, &ctx->cs);
1044
1045		if (gpio_is_valid(spi->cs_gpio)) {
1046			ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1047			if (ret) {
1048				dev_err(&spi->dev, "failed to request gpio\n");
1049				return ret;
1050			}
1051			gpio_direction_output(spi->cs_gpio,
1052					 !(spi->mode & SPI_CS_HIGH));
1053		}
1054	}
1055
1056	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1057		ret = omap2_mcspi_request_dma(spi);
1058		if (ret)
1059			dev_warn(&spi->dev, "not using DMA for McSPI (%d)\n",
1060				 ret);
1061	}
1062
1063	ret = pm_runtime_get_sync(mcspi->dev);
1064	if (ret < 0) {
1065		pm_runtime_put_noidle(mcspi->dev);
 
1066
1067		return ret;
1068	}
1069
1070	ret = omap2_mcspi_setup_transfer(spi, NULL);
 
 
 
1071	pm_runtime_mark_last_busy(mcspi->dev);
1072	pm_runtime_put_autosuspend(mcspi->dev);
1073
1074	return ret;
1075}
1076
1077static void omap2_mcspi_cleanup(struct spi_device *spi)
1078{
1079	struct omap2_mcspi	*mcspi;
1080	struct omap2_mcspi_dma	*mcspi_dma;
1081	struct omap2_mcspi_cs	*cs;
1082
1083	mcspi = spi_master_get_devdata(spi->master);
1084
1085	if (spi->controller_state) {
1086		/* Unlink controller state from context save list */
1087		cs = spi->controller_state;
1088		list_del(&cs->node);
1089
1090		kfree(cs);
1091	}
1092
1093	if (spi->chip_select < spi->master->num_chipselect) {
1094		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1095
1096		if (mcspi_dma->dma_rx) {
1097			dma_release_channel(mcspi_dma->dma_rx);
1098			mcspi_dma->dma_rx = NULL;
1099		}
1100		if (mcspi_dma->dma_tx) {
1101			dma_release_channel(mcspi_dma->dma_tx);
1102			mcspi_dma->dma_tx = NULL;
1103		}
1104	}
1105
1106	if (gpio_is_valid(spi->cs_gpio))
1107		gpio_free(spi->cs_gpio);
1108}
1109
1110static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1111{
1112	struct omap2_mcspi *mcspi = data;
1113	u32 irqstat;
1114
1115	irqstat	= mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1116	if (!irqstat)
1117		return IRQ_NONE;
1118
1119	/* Disable IRQ and wakeup slave xfer task */
1120	mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1121	if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1122		complete(&mcspi->txdone);
1123
1124	return IRQ_HANDLED;
1125}
1126
1127static int omap2_mcspi_slave_abort(struct spi_master *master)
1128{
1129	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1130	struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1131
1132	mcspi->slave_aborted = true;
1133	complete(&mcspi_dma->dma_rx_completion);
1134	complete(&mcspi_dma->dma_tx_completion);
1135	complete(&mcspi->txdone);
1136
1137	return 0;
1138}
1139
1140static int omap2_mcspi_transfer_one(struct spi_master *master,
1141				    struct spi_device *spi,
1142				    struct spi_transfer *t)
1143{
1144
1145	/* We only enable one channel at a time -- the one whose message is
1146	 * -- although this controller would gladly
1147	 * arbitrate among multiple channels.  This corresponds to "single
1148	 * channel" master mode.  As a side effect, we need to manage the
1149	 * chipselect with the FORCE bit ... CS != channel enable.
1150	 */
1151
1152	struct omap2_mcspi		*mcspi;
1153	struct omap2_mcspi_dma		*mcspi_dma;
1154	struct omap2_mcspi_cs		*cs;
1155	struct omap2_mcspi_device_config *cd;
1156	int				par_override = 0;
1157	int				status = 0;
1158	u32				chconf;
1159
1160	mcspi = spi_master_get_devdata(master);
1161	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1162	cs = spi->controller_state;
1163	cd = spi->controller_data;
1164
1165	/*
1166	 * The slave driver could have changed spi->mode in which case
1167	 * it will be different from cs->mode (the current hardware setup).
1168	 * If so, set par_override (even though its not a parity issue) so
1169	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1170	 * with the correct mode on the first iteration of the loop below.
1171	 */
1172	if (spi->mode != cs->mode)
1173		par_override = 1;
1174
1175	omap2_mcspi_set_enable(spi, 0);
1176
1177	if (gpio_is_valid(spi->cs_gpio))
1178		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1179
1180	if (par_override ||
1181	    (t->speed_hz != spi->max_speed_hz) ||
1182	    (t->bits_per_word != spi->bits_per_word)) {
1183		par_override = 1;
1184		status = omap2_mcspi_setup_transfer(spi, t);
1185		if (status < 0)
1186			goto out;
1187		if (t->speed_hz == spi->max_speed_hz &&
1188		    t->bits_per_word == spi->bits_per_word)
1189			par_override = 0;
1190	}
1191	if (cd && cd->cs_per_word) {
1192		chconf = mcspi->ctx.modulctrl;
1193		chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1194		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1195		mcspi->ctx.modulctrl =
1196			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1197	}
1198
1199	chconf = mcspi_cached_chconf0(spi);
1200	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1201	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1202
1203	if (t->tx_buf == NULL)
1204		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1205	else if (t->rx_buf == NULL)
1206		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1207
1208	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1209		/* Turbo mode is for more than one word */
1210		if (t->len > ((cs->word_len + 7) >> 3))
1211			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1212	}
1213
1214	mcspi_write_chconf0(spi, chconf);
1215
1216	if (t->len) {
1217		unsigned	count;
1218
1219		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1220		    master->cur_msg_mapped &&
1221		    master->can_dma(master, spi, t))
1222			omap2_mcspi_set_fifo(spi, t, 1);
1223
1224		omap2_mcspi_set_enable(spi, 1);
1225
1226		/* RX_ONLY mode needs dummy data in TX reg */
1227		if (t->tx_buf == NULL)
1228			writel_relaxed(0, cs->base
1229					+ OMAP2_MCSPI_TX0);
1230
1231		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1232		    master->cur_msg_mapped &&
1233		    master->can_dma(master, spi, t))
1234			count = omap2_mcspi_txrx_dma(spi, t);
1235		else
1236			count = omap2_mcspi_txrx_pio(spi, t);
1237
1238		if (count != t->len) {
1239			status = -EIO;
1240			goto out;
1241		}
1242	}
1243
1244	omap2_mcspi_set_enable(spi, 0);
1245
1246	if (mcspi->fifo_depth > 0)
1247		omap2_mcspi_set_fifo(spi, t, 0);
1248
1249out:
1250	/* Restore defaults if they were overriden */
1251	if (par_override) {
1252		par_override = 0;
1253		status = omap2_mcspi_setup_transfer(spi, NULL);
1254	}
1255
1256	if (cd && cd->cs_per_word) {
1257		chconf = mcspi->ctx.modulctrl;
1258		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1259		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1260		mcspi->ctx.modulctrl =
1261			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1262	}
1263
1264	omap2_mcspi_set_enable(spi, 0);
1265
1266	if (gpio_is_valid(spi->cs_gpio))
1267		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1268
1269	if (mcspi->fifo_depth > 0 && t)
1270		omap2_mcspi_set_fifo(spi, t, 0);
1271
1272	return status;
1273}
1274
1275static int omap2_mcspi_prepare_message(struct spi_master *master,
1276				       struct spi_message *msg)
1277{
1278	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1279	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1280	struct omap2_mcspi_cs	*cs;
 
 
1281
1282	/* Only a single channel can have the FORCE bit enabled
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1283	 * in its chconf0 register.
1284	 * Scan all channels and disable them except the current one.
1285	 * A FORCE can remain from a last transfer having cs_change enabled
 
 
1286	 */
1287	list_for_each_entry(cs, &ctx->cs, node) {
1288		if (msg->spi->controller_state == cs)
1289			continue;
 
1290
1291		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1292			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1293			writel_relaxed(cs->chconf0,
1294					cs->base + OMAP2_MCSPI_CHCONF0);
1295			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1296		}
1297	}
1298
1299	return 0;
1300}
1301
1302static bool omap2_mcspi_can_dma(struct spi_master *master,
1303				struct spi_device *spi,
1304				struct spi_transfer *xfer)
1305{
1306	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1307	struct omap2_mcspi_dma *mcspi_dma =
1308		&mcspi->dma_channels[spi->chip_select];
1309
1310	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1311		return false;
1312
1313	if (spi_controller_is_slave(master))
1314		return true;
1315
 
 
 
1316	return (xfer->len >= DMA_MIN_BYTES);
1317}
1318
 
 
 
 
 
 
 
 
 
 
 
 
1319static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1320{
1321	struct spi_master	*master = mcspi->master;
1322	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1323	int			ret = 0;
1324
1325	ret = pm_runtime_get_sync(mcspi->dev);
1326	if (ret < 0) {
1327		pm_runtime_put_noidle(mcspi->dev);
1328
1329		return ret;
1330	}
1331
1332	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1333			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1334	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1335
1336	omap2_mcspi_set_mode(master);
1337	pm_runtime_mark_last_busy(mcspi->dev);
1338	pm_runtime_put_autosuspend(mcspi->dev);
1339	return 0;
1340}
1341
 
 
 
 
 
 
 
 
 
 
 
1342/*
1343 * When SPI wake up from off-mode, CS is in activate state. If it was in
1344 * inactive state when driver was suspend, then force it to inactive state at
1345 * wake up.
1346 */
1347static int omap_mcspi_runtime_resume(struct device *dev)
1348{
1349	struct spi_master *master = dev_get_drvdata(dev);
1350	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1351	struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1352	struct omap2_mcspi_cs *cs;
 
 
 
 
 
1353
1354	/* McSPI: context restore */
1355	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1356	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1357
1358	list_for_each_entry(cs, &ctx->cs, node) {
1359		/*
1360		 * We need to toggle CS state for OMAP take this
1361		 * change in account.
1362		 */
1363		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1364			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1365			writel_relaxed(cs->chconf0,
1366				       cs->base + OMAP2_MCSPI_CHCONF0);
1367			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1368			writel_relaxed(cs->chconf0,
1369				       cs->base + OMAP2_MCSPI_CHCONF0);
1370		} else {
1371			writel_relaxed(cs->chconf0,
1372				       cs->base + OMAP2_MCSPI_CHCONF0);
1373		}
1374	}
1375
1376	return 0;
1377}
1378
1379static struct omap2_mcspi_platform_config omap2_pdata = {
1380	.regs_offset = 0,
1381};
1382
1383static struct omap2_mcspi_platform_config omap4_pdata = {
1384	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1385};
1386
 
 
 
 
 
1387static const struct of_device_id omap_mcspi_of_match[] = {
1388	{
1389		.compatible = "ti,omap2-mcspi",
1390		.data = &omap2_pdata,
1391	},
1392	{
1393		.compatible = "ti,omap4-mcspi",
1394		.data = &omap4_pdata,
1395	},
 
 
 
 
1396	{ },
1397};
1398MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1399
1400static int omap2_mcspi_probe(struct platform_device *pdev)
1401{
1402	struct spi_master	*master;
1403	const struct omap2_mcspi_platform_config *pdata;
1404	struct omap2_mcspi	*mcspi;
1405	struct resource		*r;
1406	int			status = 0, i;
1407	u32			regs_offset = 0;
1408	struct device_node	*node = pdev->dev.of_node;
1409	const struct of_device_id *match;
1410
1411	if (of_property_read_bool(node, "spi-slave"))
1412		master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1413	else
1414		master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1415	if (!master)
1416		return -ENOMEM;
1417
1418	/* the spi->mode bits understood by this driver: */
1419	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1420	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1421	master->setup = omap2_mcspi_setup;
1422	master->auto_runtime_pm = true;
1423	master->prepare_message = omap2_mcspi_prepare_message;
1424	master->can_dma = omap2_mcspi_can_dma;
1425	master->transfer_one = omap2_mcspi_transfer_one;
1426	master->set_cs = omap2_mcspi_set_cs;
1427	master->cleanup = omap2_mcspi_cleanup;
1428	master->slave_abort = omap2_mcspi_slave_abort;
1429	master->dev.of_node = node;
1430	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1431	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1432
1433	platform_set_drvdata(pdev, master);
1434
1435	mcspi = spi_master_get_devdata(master);
1436	mcspi->master = master;
1437
1438	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1439	if (match) {
1440		u32 num_cs = 1; /* default number of chipselect */
1441		pdata = match->data;
1442
1443		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1444		master->num_chipselect = num_cs;
1445		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1446			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1447	} else {
1448		pdata = dev_get_platdata(&pdev->dev);
1449		master->num_chipselect = pdata->num_cs;
1450		mcspi->pin_dir = pdata->pin_dir;
1451	}
1452	regs_offset = pdata->regs_offset;
 
 
 
 
1453
1454	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1455	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1456	if (IS_ERR(mcspi->base)) {
1457		status = PTR_ERR(mcspi->base);
1458		goto free_master;
1459	}
1460	mcspi->phys = r->start + regs_offset;
1461	mcspi->base += regs_offset;
1462
1463	mcspi->dev = &pdev->dev;
1464
1465	INIT_LIST_HEAD(&mcspi->ctx.cs);
1466
1467	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1468					   sizeof(struct omap2_mcspi_dma),
1469					   GFP_KERNEL);
1470	if (mcspi->dma_channels == NULL) {
1471		status = -ENOMEM;
1472		goto free_master;
1473	}
1474
1475	for (i = 0; i < master->num_chipselect; i++) {
1476		sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1477		sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
 
 
 
 
 
1478	}
1479
1480	status = platform_get_irq(pdev, 0);
1481	if (status == -EPROBE_DEFER)
1482		goto free_master;
1483	if (status < 0) {
1484		dev_err(&pdev->dev, "no irq resource found\n");
1485		goto free_master;
1486	}
1487	init_completion(&mcspi->txdone);
1488	status = devm_request_irq(&pdev->dev, status,
1489				  omap2_mcspi_irq_handler, 0, pdev->name,
1490				  mcspi);
1491	if (status) {
1492		dev_err(&pdev->dev, "Cannot request IRQ");
1493		goto free_master;
 
 
 
 
 
 
 
1494	}
 
 
 
 
 
 
1495
1496	pm_runtime_use_autosuspend(&pdev->dev);
1497	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1498	pm_runtime_enable(&pdev->dev);
1499
1500	status = omap2_mcspi_controller_setup(mcspi);
1501	if (status < 0)
1502		goto disable_pm;
1503
1504	status = devm_spi_register_controller(&pdev->dev, master);
1505	if (status < 0)
1506		goto disable_pm;
1507
1508	return status;
1509
1510disable_pm:
1511	pm_runtime_dont_use_autosuspend(&pdev->dev);
1512	pm_runtime_put_sync(&pdev->dev);
1513	pm_runtime_disable(&pdev->dev);
1514free_master:
1515	spi_master_put(master);
 
1516	return status;
1517}
1518
1519static int omap2_mcspi_remove(struct platform_device *pdev)
1520{
1521	struct spi_master *master = platform_get_drvdata(pdev);
1522	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 
 
1523
1524	pm_runtime_dont_use_autosuspend(mcspi->dev);
1525	pm_runtime_put_sync(mcspi->dev);
1526	pm_runtime_disable(&pdev->dev);
1527
1528	return 0;
1529}
1530
1531/* work with hotplug and coldplug */
1532MODULE_ALIAS("platform:omap2_mcspi");
1533
1534static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1535{
1536	struct spi_master *master = dev_get_drvdata(dev);
1537	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1538	int error;
1539
1540	error = pinctrl_pm_select_sleep_state(dev);
1541	if (error)
1542		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1543			 __func__, error);
1544
1545	error = spi_master_suspend(master);
1546	if (error)
1547		dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1548			 __func__, error);
1549
1550	return pm_runtime_force_suspend(dev);
1551}
1552
1553static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1554{
1555	struct spi_master *master = dev_get_drvdata(dev);
1556	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1557	int error;
1558
1559	error = pinctrl_pm_select_default_state(dev);
1560	if (error)
1561		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1562			 __func__, error);
1563
1564	error = spi_master_resume(master);
1565	if (error)
1566		dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1567			 __func__, error);
1568
1569	return pm_runtime_force_resume(dev);
1570}
1571
1572static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1573	SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1574				omap2_mcspi_resume)
1575	.runtime_resume	= omap_mcspi_runtime_resume,
 
1576};
1577
1578static struct platform_driver omap2_mcspi_driver = {
1579	.driver = {
1580		.name =		"omap2_mcspi",
1581		.pm =		&omap2_mcspi_pm_ops,
1582		.of_match_table = omap_mcspi_of_match,
1583	},
1584	.probe =	omap2_mcspi_probe,
1585	.remove =	omap2_mcspi_remove,
1586};
1587
1588module_platform_driver(omap2_mcspi_driver);
 
1589MODULE_LICENSE("GPL");