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v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * OMAP2 McSPI controller driver
   4 *
   5 * Copyright (C) 2005, 2006 Nokia Corporation
   6 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   7 *		Juha Yrjola <juha.yrjola@nokia.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/interrupt.h>
  12#include <linux/module.h>
  13#include <linux/device.h>
  14#include <linux/delay.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/dmaengine.h>
  17#include <linux/pinctrl/consumer.h>
  18#include <linux/platform_device.h>
  19#include <linux/err.h>
  20#include <linux/clk.h>
  21#include <linux/io.h>
  22#include <linux/slab.h>
  23#include <linux/pm_runtime.h>
  24#include <linux/of.h>
  25#include <linux/of_device.h>
  26#include <linux/gcd.h>
  27
  28#include <linux/spi/spi.h>
  29
  30#include <linux/platform_data/spi-omap2-mcspi.h>
  31
  32#define OMAP2_MCSPI_MAX_FREQ		48000000
  33#define OMAP2_MCSPI_MAX_DIVIDER		4096
  34#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  35#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  36#define SPI_AUTOSUSPEND_TIMEOUT		2000
  37
  38#define OMAP2_MCSPI_REVISION		0x00
  39#define OMAP2_MCSPI_SYSSTATUS		0x14
  40#define OMAP2_MCSPI_IRQSTATUS		0x18
  41#define OMAP2_MCSPI_IRQENABLE		0x1c
  42#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  43#define OMAP2_MCSPI_SYST		0x24
  44#define OMAP2_MCSPI_MODULCTRL		0x28
  45#define OMAP2_MCSPI_XFERLEVEL		0x7c
  46
  47/* per-channel banks, 0x14 bytes each, first is: */
  48#define OMAP2_MCSPI_CHCONF0		0x2c
  49#define OMAP2_MCSPI_CHSTAT0		0x30
  50#define OMAP2_MCSPI_CHCTRL0		0x34
  51#define OMAP2_MCSPI_TX0			0x38
  52#define OMAP2_MCSPI_RX0			0x3c
  53
  54/* per-register bitmasks: */
  55#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  56
  57#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  58#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  59#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  60
  61#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  62#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  63#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  64#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  65#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  66#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  67#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  68#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  69#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  70#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  71#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  72#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  73#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  74#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  75#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  76#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  77#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  78#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  79
  80#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  81#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  82#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  83#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  84
  85#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
  86#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
  87
  88#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
  89
  90/* We have 2 DMA channels per CS, one for RX and one for TX */
  91struct omap2_mcspi_dma {
  92	struct dma_chan *dma_tx;
  93	struct dma_chan *dma_rx;
  94
 
 
 
  95	struct completion dma_tx_completion;
  96	struct completion dma_rx_completion;
  97
  98	char dma_rx_ch_name[14];
  99	char dma_tx_ch_name[14];
 100};
 101
 102/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 103 * cache operations; better heuristics consider wordsize and bitrate.
 104 */
 105#define DMA_MIN_BYTES			160
 106
 107
 108/*
 109 * Used for context save and restore, structure members to be updated whenever
 110 * corresponding registers are modified.
 111 */
 112struct omap2_mcspi_regs {
 113	u32 modulctrl;
 114	u32 wakeupenable;
 115	struct list_head cs;
 116};
 117
 118struct omap2_mcspi {
 119	struct completion	txdone;
 120	struct spi_master	*master;
 121	/* Virtual base address of the controller */
 122	void __iomem		*base;
 123	unsigned long		phys;
 124	/* SPI1 has 4 channels, while SPI2 has 2 */
 125	struct omap2_mcspi_dma	*dma_channels;
 126	struct device		*dev;
 127	struct omap2_mcspi_regs ctx;
 128	int			fifo_depth;
 129	bool			slave_aborted;
 130	unsigned int		pin_dir:1;
 131	size_t			max_xfer_len;
 132};
 133
 134struct omap2_mcspi_cs {
 135	void __iomem		*base;
 136	unsigned long		phys;
 137	int			word_len;
 138	u16			mode;
 139	struct list_head	node;
 140	/* Context save and restore shadow register */
 141	u32			chconf0, chctrl0;
 142};
 143
 144static inline void mcspi_write_reg(struct spi_master *master,
 145		int idx, u32 val)
 146{
 147	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 148
 149	writel_relaxed(val, mcspi->base + idx);
 150}
 151
 152static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 153{
 154	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 155
 156	return readl_relaxed(mcspi->base + idx);
 157}
 158
 159static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 160		int idx, u32 val)
 161{
 162	struct omap2_mcspi_cs	*cs = spi->controller_state;
 163
 164	writel_relaxed(val, cs->base +  idx);
 165}
 166
 167static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 168{
 169	struct omap2_mcspi_cs	*cs = spi->controller_state;
 170
 171	return readl_relaxed(cs->base + idx);
 172}
 173
 174static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 175{
 176	struct omap2_mcspi_cs *cs = spi->controller_state;
 177
 178	return cs->chconf0;
 179}
 180
 181static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 182{
 183	struct omap2_mcspi_cs *cs = spi->controller_state;
 184
 185	cs->chconf0 = val;
 186	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 187	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 188}
 189
 190static inline int mcspi_bytes_per_word(int word_len)
 191{
 192	if (word_len <= 8)
 193		return 1;
 194	else if (word_len <= 16)
 195		return 2;
 196	else /* word_len <= 32 */
 197		return 4;
 198}
 199
 200static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 201		int is_read, int enable)
 202{
 203	u32 l, rw;
 204
 205	l = mcspi_cached_chconf0(spi);
 206
 207	if (is_read) /* 1 is read, 0 write */
 208		rw = OMAP2_MCSPI_CHCONF_DMAR;
 209	else
 210		rw = OMAP2_MCSPI_CHCONF_DMAW;
 211
 212	if (enable)
 213		l |= rw;
 214	else
 215		l &= ~rw;
 216
 217	mcspi_write_chconf0(spi, l);
 218}
 219
 220static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 221{
 222	struct omap2_mcspi_cs *cs = spi->controller_state;
 223	u32 l;
 224
 225	l = cs->chctrl0;
 226	if (enable)
 227		l |= OMAP2_MCSPI_CHCTRL_EN;
 228	else
 229		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 230	cs->chctrl0 = l;
 231	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 232	/* Flash post-writes */
 233	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 234}
 235
 236static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
 237{
 238	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 239	u32 l;
 240
 241	/* The controller handles the inverted chip selects
 242	 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
 243	 * the inversion from the core spi_set_cs function.
 244	 */
 245	if (spi->mode & SPI_CS_HIGH)
 246		enable = !enable;
 247
 248	if (spi->controller_state) {
 249		int err = pm_runtime_resume_and_get(mcspi->dev);
 250		if (err < 0) {
 251			dev_err(mcspi->dev, "failed to get sync: %d\n", err);
 252			return;
 253		}
 254
 255		l = mcspi_cached_chconf0(spi);
 256
 257		if (enable)
 258			l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 259		else
 260			l |= OMAP2_MCSPI_CHCONF_FORCE;
 261
 262		mcspi_write_chconf0(spi, l);
 263
 264		pm_runtime_mark_last_busy(mcspi->dev);
 265		pm_runtime_put_autosuspend(mcspi->dev);
 266	}
 267}
 268
 269static void omap2_mcspi_set_mode(struct spi_master *master)
 270{
 271	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 272	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 273	u32 l;
 274
 275	/*
 276	 * Choose master or slave mode
 
 277	 */
 278	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 279	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
 280	if (spi_controller_is_slave(master)) {
 281		l |= (OMAP2_MCSPI_MODULCTRL_MS);
 282	} else {
 283		l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
 284		l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 285	}
 286	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 287
 288	ctx->modulctrl = l;
 289}
 290
 291static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 292				struct spi_transfer *t, int enable)
 293{
 294	struct spi_master *master = spi->master;
 295	struct omap2_mcspi_cs *cs = spi->controller_state;
 296	struct omap2_mcspi *mcspi;
 297	unsigned int wcnt;
 298	int max_fifo_depth, bytes_per_word;
 299	u32 chconf, xferlevel;
 300
 301	mcspi = spi_master_get_devdata(master);
 302
 303	chconf = mcspi_cached_chconf0(spi);
 304	if (enable) {
 305		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 306		if (t->len % bytes_per_word != 0)
 307			goto disable_fifo;
 308
 309		if (t->rx_buf != NULL && t->tx_buf != NULL)
 310			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 311		else
 312			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 313
 
 
 
 
 314		wcnt = t->len / bytes_per_word;
 315		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 316			goto disable_fifo;
 317
 318		xferlevel = wcnt << 16;
 319		if (t->rx_buf != NULL) {
 320			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 321			xferlevel |= (bytes_per_word - 1) << 8;
 322		}
 323
 324		if (t->tx_buf != NULL) {
 325			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 326			xferlevel |= bytes_per_word - 1;
 327		}
 328
 329		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 330		mcspi_write_chconf0(spi, chconf);
 331		mcspi->fifo_depth = max_fifo_depth;
 332
 333		return;
 334	}
 335
 336disable_fifo:
 337	if (t->rx_buf != NULL)
 338		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 339
 340	if (t->tx_buf != NULL)
 341		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 342
 343	mcspi_write_chconf0(spi, chconf);
 344	mcspi->fifo_depth = 0;
 345}
 346
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 347static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 348{
 349	unsigned long timeout;
 350
 351	timeout = jiffies + msecs_to_jiffies(1000);
 352	while (!(readl_relaxed(reg) & bit)) {
 353		if (time_after(jiffies, timeout)) {
 354			if (!(readl_relaxed(reg) & bit))
 355				return -ETIMEDOUT;
 356			else
 357				return 0;
 358		}
 359		cpu_relax();
 360	}
 361	return 0;
 362}
 363
 364static int mcspi_wait_for_completion(struct  omap2_mcspi *mcspi,
 365				     struct completion *x)
 366{
 367	if (spi_controller_is_slave(mcspi->master)) {
 368		if (wait_for_completion_interruptible(x) ||
 369		    mcspi->slave_aborted)
 370			return -EINTR;
 371	} else {
 372		wait_for_completion(x);
 373	}
 374
 375	return 0;
 376}
 377
 378static void omap2_mcspi_rx_callback(void *data)
 379{
 380	struct spi_device *spi = data;
 381	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 382	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 383
 384	/* We must disable the DMA RX request */
 385	omap2_mcspi_set_dma_req(spi, 1, 0);
 386
 387	complete(&mcspi_dma->dma_rx_completion);
 388}
 389
 390static void omap2_mcspi_tx_callback(void *data)
 391{
 392	struct spi_device *spi = data;
 393	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 394	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 395
 396	/* We must disable the DMA TX request */
 397	omap2_mcspi_set_dma_req(spi, 0, 0);
 398
 399	complete(&mcspi_dma->dma_tx_completion);
 400}
 401
 402static void omap2_mcspi_tx_dma(struct spi_device *spi,
 403				struct spi_transfer *xfer,
 404				struct dma_slave_config cfg)
 405{
 406	struct omap2_mcspi	*mcspi;
 407	struct omap2_mcspi_dma  *mcspi_dma;
 408	struct dma_async_tx_descriptor *tx;
 409
 410	mcspi = spi_master_get_devdata(spi->master);
 411	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 
 412
 413	dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 414
 415	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
 416				     xfer->tx_sg.nents,
 417				     DMA_MEM_TO_DEV,
 418				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 419	if (tx) {
 420		tx->callback = omap2_mcspi_tx_callback;
 421		tx->callback_param = spi;
 422		dmaengine_submit(tx);
 423	} else {
 424		/* FIXME: fall back to PIO? */
 
 
 
 
 
 
 
 425	}
 426	dma_async_issue_pending(mcspi_dma->dma_tx);
 427	omap2_mcspi_set_dma_req(spi, 0, 1);
 
 428}
 429
 430static unsigned
 431omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 432				struct dma_slave_config cfg,
 433				unsigned es)
 434{
 435	struct omap2_mcspi	*mcspi;
 436	struct omap2_mcspi_dma  *mcspi_dma;
 437	unsigned int		count, transfer_reduction = 0;
 438	struct scatterlist	*sg_out[2];
 439	int			nb_sizes = 0, out_mapped_nents[2], ret, x;
 440	size_t			sizes[2];
 441	u32			l;
 442	int			elements = 0;
 443	int			word_len, element_count;
 444	struct omap2_mcspi_cs	*cs = spi->controller_state;
 445	void __iomem		*chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 446	struct dma_async_tx_descriptor *tx;
 447
 448	mcspi = spi_master_get_devdata(spi->master);
 449	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 450	count = xfer->len;
 
 451
 452	/*
 453	 *  In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
 454	 *  it mentions reducing DMA transfer length by one element in master
 455	 *  normal mode.
 456	 */
 457	if (mcspi->fifo_depth == 0)
 458		transfer_reduction = es;
 459
 460	word_len = cs->word_len;
 461	l = mcspi_cached_chconf0(spi);
 462
 463	if (word_len <= 8)
 464		element_count = count;
 465	else if (word_len <= 16)
 466		element_count = count >> 1;
 467	else /* word_len <= 32 */
 468		element_count = count >> 2;
 469
 470
 471	dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 472
 473	/*
 474	 *  Reduce DMA transfer length by one more if McSPI is
 475	 *  configured in turbo mode.
 476	 */
 477	if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 478		transfer_reduction += es;
 479
 480	if (transfer_reduction) {
 481		/* Split sgl into two. The second sgl won't be used. */
 482		sizes[0] = count - transfer_reduction;
 483		sizes[1] = transfer_reduction;
 484		nb_sizes = 2;
 485	} else {
 486		/*
 487		 * Don't bother splitting the sgl. This essentially
 488		 * clones the original sgl.
 489		 */
 490		sizes[0] = count;
 491		nb_sizes = 1;
 492	}
 493
 494	ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
 495		       sizes, sg_out, out_mapped_nents, GFP_KERNEL);
 496
 497	if (ret < 0) {
 498		dev_err(&spi->dev, "sg_split failed\n");
 499		return 0;
 500	}
 501
 502	tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
 503				     out_mapped_nents[0], DMA_DEV_TO_MEM,
 504				     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 505	if (tx) {
 506		tx->callback = omap2_mcspi_rx_callback;
 507		tx->callback_param = spi;
 508		dmaengine_submit(tx);
 509	} else {
 510		/* FIXME: fall back to PIO? */
 511	}
 512
 513	dma_async_issue_pending(mcspi_dma->dma_rx);
 514	omap2_mcspi_set_dma_req(spi, 1, 1);
 515
 516	ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
 517	if (ret || mcspi->slave_aborted) {
 518		dmaengine_terminate_sync(mcspi_dma->dma_rx);
 519		omap2_mcspi_set_dma_req(spi, 1, 0);
 520		return 0;
 521	}
 522
 523	for (x = 0; x < nb_sizes; x++)
 524		kfree(sg_out[x]);
 525
 526	if (mcspi->fifo_depth > 0)
 527		return count;
 528
 529	/*
 530	 *  Due to the DMA transfer length reduction the missing bytes must
 531	 *  be read manually to receive all of the expected data.
 532	 */
 533	omap2_mcspi_set_enable(spi, 0);
 534
 535	elements = element_count - 1;
 536
 537	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 538		elements--;
 539
 540		if (!mcspi_wait_for_reg_bit(chstat_reg,
 541					    OMAP2_MCSPI_CHSTAT_RXS)) {
 542			u32 w;
 543
 544			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 545			if (word_len <= 8)
 546				((u8 *)xfer->rx_buf)[elements++] = w;
 547			else if (word_len <= 16)
 548				((u16 *)xfer->rx_buf)[elements++] = w;
 549			else /* word_len <= 32 */
 550				((u32 *)xfer->rx_buf)[elements++] = w;
 551		} else {
 552			int bytes_per_word = mcspi_bytes_per_word(word_len);
 553			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 554			count -= (bytes_per_word << 1);
 555			omap2_mcspi_set_enable(spi, 1);
 556			return count;
 557		}
 558	}
 559	if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
 
 560		u32 w;
 561
 562		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 563		if (word_len <= 8)
 564			((u8 *)xfer->rx_buf)[elements] = w;
 565		else if (word_len <= 16)
 566			((u16 *)xfer->rx_buf)[elements] = w;
 567		else /* word_len <= 32 */
 568			((u32 *)xfer->rx_buf)[elements] = w;
 569	} else {
 570		dev_err(&spi->dev, "DMA RX last word empty\n");
 571		count -= mcspi_bytes_per_word(word_len);
 572	}
 573	omap2_mcspi_set_enable(spi, 1);
 574	return count;
 575}
 576
 577static unsigned
 578omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 579{
 580	struct omap2_mcspi	*mcspi;
 581	struct omap2_mcspi_cs	*cs = spi->controller_state;
 582	struct omap2_mcspi_dma  *mcspi_dma;
 583	unsigned int		count;
 
 584	u8			*rx;
 585	const u8		*tx;
 586	struct dma_slave_config	cfg;
 587	enum dma_slave_buswidth width;
 588	unsigned es;
 
 589	void __iomem		*chstat_reg;
 590	void __iomem            *irqstat_reg;
 591	int			wait_res;
 592
 593	mcspi = spi_master_get_devdata(spi->master);
 594	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 
 
 595
 596	if (cs->word_len <= 8) {
 597		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 598		es = 1;
 599	} else if (cs->word_len <= 16) {
 600		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 601		es = 2;
 602	} else {
 603		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 604		es = 4;
 605	}
 606
 607	count = xfer->len;
 
 
 
 
 
 
 
 
 608
 609	memset(&cfg, 0, sizeof(cfg));
 610	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 611	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 612	cfg.src_addr_width = width;
 613	cfg.dst_addr_width = width;
 614	cfg.src_maxburst = 1;
 615	cfg.dst_maxburst = 1;
 616
 617	rx = xfer->rx_buf;
 618	tx = xfer->tx_buf;
 619
 620	mcspi->slave_aborted = false;
 621	reinit_completion(&mcspi_dma->dma_tx_completion);
 622	reinit_completion(&mcspi_dma->dma_rx_completion);
 623	reinit_completion(&mcspi->txdone);
 624	if (tx) {
 625		/* Enable EOW IRQ to know end of tx in slave mode */
 626		if (spi_controller_is_slave(spi->master))
 627			mcspi_write_reg(spi->master,
 628					OMAP2_MCSPI_IRQENABLE,
 629					OMAP2_MCSPI_IRQSTATUS_EOW);
 630		omap2_mcspi_tx_dma(spi, xfer, cfg);
 631	}
 632
 633	if (rx != NULL)
 634		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 635
 636	if (tx != NULL) {
 637		int ret;
 638
 639		ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
 640		if (ret || mcspi->slave_aborted) {
 641			dmaengine_terminate_sync(mcspi_dma->dma_tx);
 642			omap2_mcspi_set_dma_req(spi, 0, 0);
 643			return 0;
 644		}
 645
 646		if (spi_controller_is_slave(mcspi->master)) {
 647			ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
 648			if (ret || mcspi->slave_aborted)
 649				return 0;
 650		}
 651
 652		if (mcspi->fifo_depth > 0) {
 653			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 654
 655			if (mcspi_wait_for_reg_bit(irqstat_reg,
 656						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 657				dev_err(&spi->dev, "EOW timed out\n");
 658
 659			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 660					OMAP2_MCSPI_IRQSTATUS_EOW);
 661		}
 662
 663		/* for TX_ONLY mode, be sure all words have shifted out */
 664		if (rx == NULL) {
 665			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 666			if (mcspi->fifo_depth > 0) {
 667				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 668						OMAP2_MCSPI_CHSTAT_TXFFE);
 669				if (wait_res < 0)
 670					dev_err(&spi->dev, "TXFFE timed out\n");
 671			} else {
 672				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 673						OMAP2_MCSPI_CHSTAT_TXS);
 674				if (wait_res < 0)
 675					dev_err(&spi->dev, "TXS timed out\n");
 676			}
 677			if (wait_res >= 0 &&
 678				(mcspi_wait_for_reg_bit(chstat_reg,
 679					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 680				dev_err(&spi->dev, "EOT timed out\n");
 681		}
 682	}
 683	return count;
 684}
 685
 686static unsigned
 687omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 688{
 
 689	struct omap2_mcspi_cs	*cs = spi->controller_state;
 690	unsigned int		count, c;
 691	u32			l;
 692	void __iomem		*base = cs->base;
 693	void __iomem		*tx_reg;
 694	void __iomem		*rx_reg;
 695	void __iomem		*chstat_reg;
 696	int			word_len;
 697
 
 698	count = xfer->len;
 699	c = count;
 700	word_len = cs->word_len;
 701
 702	l = mcspi_cached_chconf0(spi);
 703
 704	/* We store the pre-calculated register addresses on stack to speed
 705	 * up the transfer loop. */
 706	tx_reg		= base + OMAP2_MCSPI_TX0;
 707	rx_reg		= base + OMAP2_MCSPI_RX0;
 708	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 709
 710	if (c < (word_len>>3))
 711		return 0;
 712
 713	if (word_len <= 8) {
 714		u8		*rx;
 715		const u8	*tx;
 716
 717		rx = xfer->rx_buf;
 718		tx = xfer->tx_buf;
 719
 720		do {
 721			c -= 1;
 722			if (tx != NULL) {
 723				if (mcspi_wait_for_reg_bit(chstat_reg,
 724						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 725					dev_err(&spi->dev, "TXS timed out\n");
 726					goto out;
 727				}
 728				dev_vdbg(&spi->dev, "write-%d %02x\n",
 729						word_len, *tx);
 730				writel_relaxed(*tx++, tx_reg);
 731			}
 732			if (rx != NULL) {
 733				if (mcspi_wait_for_reg_bit(chstat_reg,
 734						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 735					dev_err(&spi->dev, "RXS timed out\n");
 736					goto out;
 737				}
 738
 739				if (c == 1 && tx == NULL &&
 740				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 741					omap2_mcspi_set_enable(spi, 0);
 742					*rx++ = readl_relaxed(rx_reg);
 743					dev_vdbg(&spi->dev, "read-%d %02x\n",
 744						    word_len, *(rx - 1));
 745					if (mcspi_wait_for_reg_bit(chstat_reg,
 746						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 747						dev_err(&spi->dev,
 748							"RXS timed out\n");
 749						goto out;
 750					}
 751					c = 0;
 752				} else if (c == 0 && tx == NULL) {
 753					omap2_mcspi_set_enable(spi, 0);
 754				}
 755
 756				*rx++ = readl_relaxed(rx_reg);
 757				dev_vdbg(&spi->dev, "read-%d %02x\n",
 758						word_len, *(rx - 1));
 759			}
 760			/* Add word delay between each word */
 761			spi_delay_exec(&xfer->word_delay, xfer);
 762		} while (c);
 763	} else if (word_len <= 16) {
 764		u16		*rx;
 765		const u16	*tx;
 766
 767		rx = xfer->rx_buf;
 768		tx = xfer->tx_buf;
 769		do {
 770			c -= 2;
 771			if (tx != NULL) {
 772				if (mcspi_wait_for_reg_bit(chstat_reg,
 773						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 774					dev_err(&spi->dev, "TXS timed out\n");
 775					goto out;
 776				}
 777				dev_vdbg(&spi->dev, "write-%d %04x\n",
 778						word_len, *tx);
 779				writel_relaxed(*tx++, tx_reg);
 780			}
 781			if (rx != NULL) {
 782				if (mcspi_wait_for_reg_bit(chstat_reg,
 783						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 784					dev_err(&spi->dev, "RXS timed out\n");
 785					goto out;
 786				}
 787
 788				if (c == 2 && tx == NULL &&
 789				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 790					omap2_mcspi_set_enable(spi, 0);
 791					*rx++ = readl_relaxed(rx_reg);
 792					dev_vdbg(&spi->dev, "read-%d %04x\n",
 793						    word_len, *(rx - 1));
 794					if (mcspi_wait_for_reg_bit(chstat_reg,
 795						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 796						dev_err(&spi->dev,
 797							"RXS timed out\n");
 798						goto out;
 799					}
 800					c = 0;
 801				} else if (c == 0 && tx == NULL) {
 802					omap2_mcspi_set_enable(spi, 0);
 803				}
 804
 805				*rx++ = readl_relaxed(rx_reg);
 806				dev_vdbg(&spi->dev, "read-%d %04x\n",
 807						word_len, *(rx - 1));
 808			}
 809			/* Add word delay between each word */
 810			spi_delay_exec(&xfer->word_delay, xfer);
 811		} while (c >= 2);
 812	} else if (word_len <= 32) {
 813		u32		*rx;
 814		const u32	*tx;
 815
 816		rx = xfer->rx_buf;
 817		tx = xfer->tx_buf;
 818		do {
 819			c -= 4;
 820			if (tx != NULL) {
 821				if (mcspi_wait_for_reg_bit(chstat_reg,
 822						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 823					dev_err(&spi->dev, "TXS timed out\n");
 824					goto out;
 825				}
 826				dev_vdbg(&spi->dev, "write-%d %08x\n",
 827						word_len, *tx);
 828				writel_relaxed(*tx++, tx_reg);
 829			}
 830			if (rx != NULL) {
 831				if (mcspi_wait_for_reg_bit(chstat_reg,
 832						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 833					dev_err(&spi->dev, "RXS timed out\n");
 834					goto out;
 835				}
 836
 837				if (c == 4 && tx == NULL &&
 838				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 839					omap2_mcspi_set_enable(spi, 0);
 840					*rx++ = readl_relaxed(rx_reg);
 841					dev_vdbg(&spi->dev, "read-%d %08x\n",
 842						    word_len, *(rx - 1));
 843					if (mcspi_wait_for_reg_bit(chstat_reg,
 844						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 845						dev_err(&spi->dev,
 846							"RXS timed out\n");
 847						goto out;
 848					}
 849					c = 0;
 850				} else if (c == 0 && tx == NULL) {
 851					omap2_mcspi_set_enable(spi, 0);
 852				}
 853
 854				*rx++ = readl_relaxed(rx_reg);
 855				dev_vdbg(&spi->dev, "read-%d %08x\n",
 856						word_len, *(rx - 1));
 857			}
 858			/* Add word delay between each word */
 859			spi_delay_exec(&xfer->word_delay, xfer);
 860		} while (c >= 4);
 861	}
 862
 863	/* for TX_ONLY mode, be sure all words have shifted out */
 864	if (xfer->rx_buf == NULL) {
 865		if (mcspi_wait_for_reg_bit(chstat_reg,
 866				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 867			dev_err(&spi->dev, "TXS timed out\n");
 868		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 869				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 870			dev_err(&spi->dev, "EOT timed out\n");
 871
 872		/* disable chan to purge rx datas received in TX_ONLY transfer,
 873		 * otherwise these rx datas will affect the direct following
 874		 * RX_ONLY transfer.
 875		 */
 876		omap2_mcspi_set_enable(spi, 0);
 877	}
 878out:
 879	omap2_mcspi_set_enable(spi, 1);
 880	return count - c;
 881}
 882
 883static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 884{
 885	u32 div;
 886
 887	for (div = 0; div < 15; div++)
 888		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 889			return div;
 890
 891	return 15;
 892}
 893
 894/* called only when no transfer is active to this device */
 895static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 896		struct spi_transfer *t)
 897{
 898	struct omap2_mcspi_cs *cs = spi->controller_state;
 899	struct omap2_mcspi *mcspi;
 
 900	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 901	u8 word_len = spi->bits_per_word;
 902	u32 speed_hz = spi->max_speed_hz;
 903
 904	mcspi = spi_master_get_devdata(spi->master);
 
 905
 906	if (t != NULL && t->bits_per_word)
 907		word_len = t->bits_per_word;
 908
 909	cs->word_len = word_len;
 910
 911	if (t && t->speed_hz)
 912		speed_hz = t->speed_hz;
 913
 914	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 915	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 916		clkd = omap2_mcspi_calc_divisor(speed_hz);
 917		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 918		clkg = 0;
 919	} else {
 920		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 921		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 922		clkd = (div - 1) & 0xf;
 923		extclk = (div - 1) >> 4;
 924		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 925	}
 926
 927	l = mcspi_cached_chconf0(spi);
 928
 929	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 930	 * REVISIT: this controller could support SPI_3WIRE mode.
 931	 */
 932	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 933		l &= ~OMAP2_MCSPI_CHCONF_IS;
 934		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 935		l |= OMAP2_MCSPI_CHCONF_DPE0;
 936	} else {
 937		l |= OMAP2_MCSPI_CHCONF_IS;
 938		l |= OMAP2_MCSPI_CHCONF_DPE1;
 939		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 940	}
 941
 942	/* wordlength */
 943	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 944	l |= (word_len - 1) << 7;
 945
 946	/* set chipselect polarity; manage with FORCE */
 947	if (!(spi->mode & SPI_CS_HIGH))
 948		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 949	else
 950		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 951
 952	/* set clock divisor */
 953	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 954	l |= clkd << 2;
 955
 956	/* set clock granularity */
 957	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 958	l |= clkg;
 959	if (clkg) {
 960		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 961		cs->chctrl0 |= extclk << 8;
 962		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 963	}
 964
 965	/* set SPI mode 0..3 */
 966	if (spi->mode & SPI_CPOL)
 967		l |= OMAP2_MCSPI_CHCONF_POL;
 968	else
 969		l &= ~OMAP2_MCSPI_CHCONF_POL;
 970	if (spi->mode & SPI_CPHA)
 971		l |= OMAP2_MCSPI_CHCONF_PHA;
 972	else
 973		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 974
 975	mcspi_write_chconf0(spi, l);
 976
 977	cs->mode = spi->mode;
 978
 979	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 980			speed_hz,
 981			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 982			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 983
 984	return 0;
 985}
 986
 987/*
 988 * Note that we currently allow DMA only if we get a channel
 989 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 990 */
 991static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
 992				   struct omap2_mcspi_dma *mcspi_dma)
 993{
 994	int ret = 0;
 995
 996	mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
 997					     mcspi_dma->dma_rx_ch_name);
 998	if (IS_ERR(mcspi_dma->dma_rx)) {
 999		ret = PTR_ERR(mcspi_dma->dma_rx);
1000		mcspi_dma->dma_rx = NULL;
1001		goto no_dma;
1002	}
1003
1004	mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
1005					     mcspi_dma->dma_tx_ch_name);
1006	if (IS_ERR(mcspi_dma->dma_tx)) {
1007		ret = PTR_ERR(mcspi_dma->dma_tx);
1008		mcspi_dma->dma_tx = NULL;
1009		dma_release_channel(mcspi_dma->dma_rx);
1010		mcspi_dma->dma_rx = NULL;
1011	}
1012
1013	init_completion(&mcspi_dma->dma_rx_completion);
1014	init_completion(&mcspi_dma->dma_tx_completion);
1015
1016no_dma:
1017	return ret;
1018}
 
 
 
 
 
 
 
1019
1020static void omap2_mcspi_release_dma(struct spi_master *master)
1021{
1022	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1023	struct omap2_mcspi_dma	*mcspi_dma;
1024	int i;
1025
1026	for (i = 0; i < master->num_chipselect; i++) {
1027		mcspi_dma = &mcspi->dma_channels[i];
1028
1029		if (mcspi_dma->dma_rx) {
1030			dma_release_channel(mcspi_dma->dma_rx);
1031			mcspi_dma->dma_rx = NULL;
1032		}
1033		if (mcspi_dma->dma_tx) {
1034			dma_release_channel(mcspi_dma->dma_tx);
1035			mcspi_dma->dma_tx = NULL;
1036		}
1037	}
1038}
1039
1040static void omap2_mcspi_cleanup(struct spi_device *spi)
1041{
1042	struct omap2_mcspi_cs	*cs;
1043
1044	if (spi->controller_state) {
1045		/* Unlink controller state from context save list */
1046		cs = spi->controller_state;
1047		list_del(&cs->node);
1048
1049		kfree(cs);
1050	}
 
1051}
1052
1053static int omap2_mcspi_setup(struct spi_device *spi)
1054{
1055	bool			initial_setup = false;
1056	int			ret;
1057	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
1058	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 
1059	struct omap2_mcspi_cs	*cs = spi->controller_state;
1060
 
 
1061	if (!cs) {
1062		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1063		if (!cs)
1064			return -ENOMEM;
1065		cs->base = mcspi->base + spi->chip_select * 0x14;
1066		cs->phys = mcspi->phys + spi->chip_select * 0x14;
1067		cs->mode = 0;
1068		cs->chconf0 = 0;
1069		cs->chctrl0 = 0;
1070		spi->controller_state = cs;
1071		/* Link this to context save list */
1072		list_add_tail(&cs->node, &ctx->cs);
1073		initial_setup = true;
1074	}
1075
1076	ret = pm_runtime_resume_and_get(mcspi->dev);
1077	if (ret < 0) {
1078		if (initial_setup)
1079			omap2_mcspi_cleanup(spi);
 
1080
 
 
1081		return ret;
1082	}
1083
1084	ret = omap2_mcspi_setup_transfer(spi, NULL);
1085	if (ret && initial_setup)
1086		omap2_mcspi_cleanup(spi);
1087
1088	pm_runtime_mark_last_busy(mcspi->dev);
1089	pm_runtime_put_autosuspend(mcspi->dev);
1090
1091	return ret;
1092}
1093
1094static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1095{
1096	struct omap2_mcspi *mcspi = data;
1097	u32 irqstat;
 
1098
1099	irqstat	= mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1100	if (!irqstat)
1101		return IRQ_NONE;
1102
1103	/* Disable IRQ and wakeup slave xfer task */
1104	mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1105	if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1106		complete(&mcspi->txdone);
1107
1108	return IRQ_HANDLED;
1109}
1110
1111static int omap2_mcspi_slave_abort(struct spi_master *master)
1112{
1113	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1114	struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1115
1116	mcspi->slave_aborted = true;
1117	complete(&mcspi_dma->dma_rx_completion);
1118	complete(&mcspi_dma->dma_tx_completion);
1119	complete(&mcspi->txdone);
1120
1121	return 0;
 
 
 
1122}
1123
1124static int omap2_mcspi_transfer_one(struct spi_master *master,
1125				    struct spi_device *spi,
1126				    struct spi_transfer *t)
1127{
1128
1129	/* We only enable one channel at a time -- the one whose message is
1130	 * -- although this controller would gladly
1131	 * arbitrate among multiple channels.  This corresponds to "single
1132	 * channel" master mode.  As a side effect, we need to manage the
1133	 * chipselect with the FORCE bit ... CS != channel enable.
1134	 */
1135
1136	struct omap2_mcspi		*mcspi;
 
 
1137	struct omap2_mcspi_dma		*mcspi_dma;
 
1138	struct omap2_mcspi_cs		*cs;
1139	struct omap2_mcspi_device_config *cd;
1140	int				par_override = 0;
1141	int				status = 0;
1142	u32				chconf;
1143
1144	mcspi = spi_master_get_devdata(master);
 
1145	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1146	cs = spi->controller_state;
1147	cd = spi->controller_data;
1148
1149	/*
1150	 * The slave driver could have changed spi->mode in which case
1151	 * it will be different from cs->mode (the current hardware setup).
1152	 * If so, set par_override (even though its not a parity issue) so
1153	 * omap2_mcspi_setup_transfer will be called to configure the hardware
1154	 * with the correct mode on the first iteration of the loop below.
1155	 */
1156	if (spi->mode != cs->mode)
1157		par_override = 1;
1158
1159	omap2_mcspi_set_enable(spi, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1160
1161	if (spi->cs_gpiod)
1162		omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1163
1164	if (par_override ||
1165	    (t->speed_hz != spi->max_speed_hz) ||
1166	    (t->bits_per_word != spi->bits_per_word)) {
1167		par_override = 1;
1168		status = omap2_mcspi_setup_transfer(spi, t);
1169		if (status < 0)
1170			goto out;
1171		if (t->speed_hz == spi->max_speed_hz &&
1172		    t->bits_per_word == spi->bits_per_word)
1173			par_override = 0;
1174	}
1175	if (cd && cd->cs_per_word) {
1176		chconf = mcspi->ctx.modulctrl;
1177		chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1178		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1179		mcspi->ctx.modulctrl =
1180			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1181	}
1182
1183	chconf = mcspi_cached_chconf0(spi);
1184	chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1185	chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
 
1186
1187	if (t->tx_buf == NULL)
1188		chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1189	else if (t->rx_buf == NULL)
1190		chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1191
1192	if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1193		/* Turbo mode is for more than one word */
1194		if (t->len > ((cs->word_len + 7) >> 3))
1195			chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1196	}
1197
1198	mcspi_write_chconf0(spi, chconf);
 
 
 
 
 
 
 
 
 
1199
1200	if (t->len) {
1201		unsigned	count;
1202
1203		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1204		    master->cur_msg_mapped &&
1205		    master->can_dma(master, spi, t))
1206			omap2_mcspi_set_fifo(spi, t, 1);
1207
1208		omap2_mcspi_set_enable(spi, 1);
 
 
1209
1210		/* RX_ONLY mode needs dummy data in TX reg */
1211		if (t->tx_buf == NULL)
1212			writel_relaxed(0, cs->base
1213					+ OMAP2_MCSPI_TX0);
1214
1215		if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1216		    master->cur_msg_mapped &&
1217		    master->can_dma(master, spi, t))
1218			count = omap2_mcspi_txrx_dma(spi, t);
1219		else
1220			count = omap2_mcspi_txrx_pio(spi, t);
 
 
 
 
 
1221
1222		if (count != t->len) {
1223			status = -EIO;
1224			goto out;
 
1225		}
1226	}
1227
1228	omap2_mcspi_set_enable(spi, 0);
 
1229
1230	if (mcspi->fifo_depth > 0)
1231		omap2_mcspi_set_fifo(spi, t, 0);
 
 
 
1232
1233out:
 
 
 
 
1234	/* Restore defaults if they were overriden */
1235	if (par_override) {
1236		par_override = 0;
1237		status = omap2_mcspi_setup_transfer(spi, NULL);
1238	}
1239
 
 
 
1240	if (cd && cd->cs_per_word) {
1241		chconf = mcspi->ctx.modulctrl;
1242		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1243		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1244		mcspi->ctx.modulctrl =
1245			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1246	}
1247
1248	omap2_mcspi_set_enable(spi, 0);
1249
1250	if (spi->cs_gpiod)
1251		omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1252
1253	if (mcspi->fifo_depth > 0 && t)
1254		omap2_mcspi_set_fifo(spi, t, 0);
1255
1256	return status;
1257}
1258
1259static int omap2_mcspi_prepare_message(struct spi_master *master,
1260				       struct spi_message *msg)
1261{
1262	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1263	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1264	struct omap2_mcspi_cs	*cs;
 
1265
1266	/* Only a single channel can have the FORCE bit enabled
1267	 * in its chconf0 register.
1268	 * Scan all channels and disable them except the current one.
1269	 * A FORCE can remain from a last transfer having cs_change enabled
1270	 */
1271	list_for_each_entry(cs, &ctx->cs, node) {
1272		if (msg->spi->controller_state == cs)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1273			continue;
1274
1275		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1276			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1277			writel_relaxed(cs->chconf0,
1278					cs->base + OMAP2_MCSPI_CHCONF0);
1279			readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1280		}
1281	}
1282
 
 
1283	return 0;
1284}
1285
1286static bool omap2_mcspi_can_dma(struct spi_master *master,
1287				struct spi_device *spi,
1288				struct spi_transfer *xfer)
1289{
1290	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1291	struct omap2_mcspi_dma *mcspi_dma =
1292		&mcspi->dma_channels[spi->chip_select];
1293
1294	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1295		return false;
1296
1297	if (spi_controller_is_slave(master))
1298		return true;
1299
1300	master->dma_rx = mcspi_dma->dma_rx;
1301	master->dma_tx = mcspi_dma->dma_tx;
1302
1303	return (xfer->len >= DMA_MIN_BYTES);
1304}
1305
1306static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1307{
1308	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1309	struct omap2_mcspi_dma *mcspi_dma =
1310		&mcspi->dma_channels[spi->chip_select];
1311
1312	if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1313		return mcspi->max_xfer_len;
1314
1315	return SIZE_MAX;
1316}
1317
1318static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1319{
1320	struct spi_master	*master = mcspi->master;
1321	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1322	int			ret = 0;
1323
1324	ret = pm_runtime_resume_and_get(mcspi->dev);
1325	if (ret < 0)
1326		return ret;
1327
1328	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1329			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1330	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1331
1332	omap2_mcspi_set_mode(master);
1333	pm_runtime_mark_last_busy(mcspi->dev);
1334	pm_runtime_put_autosuspend(mcspi->dev);
1335	return 0;
1336}
1337
1338static int omap_mcspi_runtime_suspend(struct device *dev)
1339{
1340	int error;
1341
1342	error = pinctrl_pm_select_idle_state(dev);
1343	if (error)
1344		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1345
1346	return 0;
1347}
1348
1349/*
1350 * When SPI wake up from off-mode, CS is in activate state. If it was in
1351 * inactive state when driver was suspend, then force it to inactive state at
1352 * wake up.
1353 */
1354static int omap_mcspi_runtime_resume(struct device *dev)
1355{
1356	struct spi_master *master = dev_get_drvdata(dev);
1357	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1358	struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1359	struct omap2_mcspi_cs *cs;
1360	int error;
1361
1362	error = pinctrl_pm_select_default_state(dev);
1363	if (error)
1364		dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1365
1366	/* McSPI: context restore */
1367	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1368	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1369
1370	list_for_each_entry(cs, &ctx->cs, node) {
1371		/*
1372		 * We need to toggle CS state for OMAP take this
1373		 * change in account.
1374		 */
1375		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1376			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1377			writel_relaxed(cs->chconf0,
1378				       cs->base + OMAP2_MCSPI_CHCONF0);
1379			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1380			writel_relaxed(cs->chconf0,
1381				       cs->base + OMAP2_MCSPI_CHCONF0);
1382		} else {
1383			writel_relaxed(cs->chconf0,
1384				       cs->base + OMAP2_MCSPI_CHCONF0);
1385		}
1386	}
1387
1388	return 0;
1389}
1390
1391static struct omap2_mcspi_platform_config omap2_pdata = {
1392	.regs_offset = 0,
1393};
1394
1395static struct omap2_mcspi_platform_config omap4_pdata = {
1396	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1397};
1398
1399static struct omap2_mcspi_platform_config am654_pdata = {
1400	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1401	.max_xfer_len = SZ_4K - 1,
1402};
1403
1404static const struct of_device_id omap_mcspi_of_match[] = {
1405	{
1406		.compatible = "ti,omap2-mcspi",
1407		.data = &omap2_pdata,
1408	},
1409	{
1410		.compatible = "ti,omap4-mcspi",
1411		.data = &omap4_pdata,
1412	},
1413	{
1414		.compatible = "ti,am654-mcspi",
1415		.data = &am654_pdata,
1416	},
1417	{ },
1418};
1419MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1420
1421static int omap2_mcspi_probe(struct platform_device *pdev)
1422{
1423	struct spi_master	*master;
1424	const struct omap2_mcspi_platform_config *pdata;
1425	struct omap2_mcspi	*mcspi;
1426	struct resource		*r;
1427	int			status = 0, i;
1428	u32			regs_offset = 0;
 
1429	struct device_node	*node = pdev->dev.of_node;
1430	const struct of_device_id *match;
1431
1432	if (of_property_read_bool(node, "spi-slave"))
1433		master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1434	else
1435		master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1436	if (!master)
1437		return -ENOMEM;
 
1438
1439	/* the spi->mode bits understood by this driver: */
1440	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1441	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1442	master->setup = omap2_mcspi_setup;
1443	master->auto_runtime_pm = true;
1444	master->prepare_message = omap2_mcspi_prepare_message;
1445	master->can_dma = omap2_mcspi_can_dma;
1446	master->transfer_one = omap2_mcspi_transfer_one;
1447	master->set_cs = omap2_mcspi_set_cs;
1448	master->cleanup = omap2_mcspi_cleanup;
1449	master->slave_abort = omap2_mcspi_slave_abort;
1450	master->dev.of_node = node;
1451	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1452	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1453	master->use_gpio_descriptors = true;
1454
1455	platform_set_drvdata(pdev, master);
1456
1457	mcspi = spi_master_get_devdata(master);
1458	mcspi->master = master;
1459
1460	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1461	if (match) {
1462		u32 num_cs = 1; /* default number of chipselect */
1463		pdata = match->data;
1464
1465		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1466		master->num_chipselect = num_cs;
 
1467		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1468			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1469	} else {
1470		pdata = dev_get_platdata(&pdev->dev);
1471		master->num_chipselect = pdata->num_cs;
 
 
1472		mcspi->pin_dir = pdata->pin_dir;
1473	}
1474	regs_offset = pdata->regs_offset;
1475	if (pdata->max_xfer_len) {
1476		mcspi->max_xfer_len = pdata->max_xfer_len;
1477		master->max_transfer_size = omap2_mcspi_max_xfer_size;
1478	}
1479
1480	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 
 
 
 
 
 
 
 
 
1481	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1482	if (IS_ERR(mcspi->base)) {
1483		status = PTR_ERR(mcspi->base);
1484		goto free_master;
1485	}
1486	mcspi->phys = r->start + regs_offset;
1487	mcspi->base += regs_offset;
1488
1489	mcspi->dev = &pdev->dev;
1490
1491	INIT_LIST_HEAD(&mcspi->ctx.cs);
1492
1493	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1494					   sizeof(struct omap2_mcspi_dma),
1495					   GFP_KERNEL);
1496	if (mcspi->dma_channels == NULL) {
1497		status = -ENOMEM;
1498		goto free_master;
1499	}
1500
1501	for (i = 0; i < master->num_chipselect; i++) {
1502		sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1503		sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1504
1505		status = omap2_mcspi_request_dma(mcspi,
1506						 &mcspi->dma_channels[i]);
1507		if (status == -EPROBE_DEFER)
1508			goto free_master;
1509	}
 
 
 
 
 
 
 
 
 
 
1510
1511	status = platform_get_irq(pdev, 0);
1512	if (status < 0) {
1513		dev_err_probe(&pdev->dev, status, "no irq resource found\n");
1514		goto free_master;
1515	}
1516	init_completion(&mcspi->txdone);
1517	status = devm_request_irq(&pdev->dev, status,
1518				  omap2_mcspi_irq_handler, 0, pdev->name,
1519				  mcspi);
1520	if (status) {
1521		dev_err(&pdev->dev, "Cannot request IRQ");
1522		goto free_master;
1523	}
1524
1525	pm_runtime_use_autosuspend(&pdev->dev);
1526	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1527	pm_runtime_enable(&pdev->dev);
1528
1529	status = omap2_mcspi_controller_setup(mcspi);
1530	if (status < 0)
1531		goto disable_pm;
1532
1533	status = devm_spi_register_controller(&pdev->dev, master);
1534	if (status < 0)
1535		goto disable_pm;
1536
1537	return status;
1538
1539disable_pm:
1540	pm_runtime_dont_use_autosuspend(&pdev->dev);
1541	pm_runtime_put_sync(&pdev->dev);
1542	pm_runtime_disable(&pdev->dev);
1543free_master:
1544	omap2_mcspi_release_dma(master);
1545	spi_master_put(master);
1546	return status;
1547}
1548
1549static int omap2_mcspi_remove(struct platform_device *pdev)
1550{
1551	struct spi_master *master = platform_get_drvdata(pdev);
1552	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1553
1554	omap2_mcspi_release_dma(master);
1555
1556	pm_runtime_dont_use_autosuspend(mcspi->dev);
1557	pm_runtime_put_sync(mcspi->dev);
1558	pm_runtime_disable(&pdev->dev);
1559
1560	return 0;
1561}
1562
1563/* work with hotplug and coldplug */
1564MODULE_ALIAS("platform:omap2_mcspi");
1565
1566static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1567{
1568	struct spi_master *master = dev_get_drvdata(dev);
1569	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1570	int error;
1571
1572	error = pinctrl_pm_select_sleep_state(dev);
1573	if (error)
1574		dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1575			 __func__, error);
1576
1577	error = spi_master_suspend(master);
1578	if (error)
1579		dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1580			 __func__, error);
1581
1582	return pm_runtime_force_suspend(dev);
1583}
1584
1585static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1586{
1587	struct spi_master *master = dev_get_drvdata(dev);
1588	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1589	int error;
1590
1591	error = spi_master_resume(master);
1592	if (error)
1593		dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1594			 __func__, error);
1595
1596	return pm_runtime_force_resume(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1597}
 
 
 
1598
1599static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1600	SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1601				omap2_mcspi_resume)
1602	.runtime_suspend	= omap_mcspi_runtime_suspend,
1603	.runtime_resume		= omap_mcspi_runtime_resume,
1604};
1605
1606static struct platform_driver omap2_mcspi_driver = {
1607	.driver = {
1608		.name =		"omap2_mcspi",
 
1609		.pm =		&omap2_mcspi_pm_ops,
1610		.of_match_table = omap_mcspi_of_match,
1611	},
1612	.probe =	omap2_mcspi_probe,
1613	.remove =	omap2_mcspi_remove,
1614};
1615
1616module_platform_driver(omap2_mcspi_driver);
1617MODULE_LICENSE("GPL");
v3.15
 
   1/*
   2 * OMAP2 McSPI controller driver
   3 *
   4 * Copyright (C) 2005, 2006 Nokia Corporation
   5 * Author:	Samuel Ortiz <samuel.ortiz@nokia.com> and
   6 *		Juha Yrj�l� <juha.yrjola@nokia.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License as published by
  10 * the Free Software Foundation; either version 2 of the License, or
  11 * (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21 *
  22 */
  23
  24#include <linux/kernel.h>
  25#include <linux/interrupt.h>
  26#include <linux/module.h>
  27#include <linux/device.h>
  28#include <linux/delay.h>
  29#include <linux/dma-mapping.h>
  30#include <linux/dmaengine.h>
  31#include <linux/omap-dma.h>
  32#include <linux/platform_device.h>
  33#include <linux/err.h>
  34#include <linux/clk.h>
  35#include <linux/io.h>
  36#include <linux/slab.h>
  37#include <linux/pm_runtime.h>
  38#include <linux/of.h>
  39#include <linux/of_device.h>
  40#include <linux/gcd.h>
  41
  42#include <linux/spi/spi.h>
  43
  44#include <linux/platform_data/spi-omap2-mcspi.h>
  45
  46#define OMAP2_MCSPI_MAX_FREQ		48000000
  47#define OMAP2_MCSPI_MAX_DIVIDER		4096
  48#define OMAP2_MCSPI_MAX_FIFODEPTH	64
  49#define OMAP2_MCSPI_MAX_FIFOWCNT	0xFFFF
  50#define SPI_AUTOSUSPEND_TIMEOUT		2000
  51
  52#define OMAP2_MCSPI_REVISION		0x00
  53#define OMAP2_MCSPI_SYSSTATUS		0x14
  54#define OMAP2_MCSPI_IRQSTATUS		0x18
  55#define OMAP2_MCSPI_IRQENABLE		0x1c
  56#define OMAP2_MCSPI_WAKEUPENABLE	0x20
  57#define OMAP2_MCSPI_SYST		0x24
  58#define OMAP2_MCSPI_MODULCTRL		0x28
  59#define OMAP2_MCSPI_XFERLEVEL		0x7c
  60
  61/* per-channel banks, 0x14 bytes each, first is: */
  62#define OMAP2_MCSPI_CHCONF0		0x2c
  63#define OMAP2_MCSPI_CHSTAT0		0x30
  64#define OMAP2_MCSPI_CHCTRL0		0x34
  65#define OMAP2_MCSPI_TX0			0x38
  66#define OMAP2_MCSPI_RX0			0x3c
  67
  68/* per-register bitmasks: */
  69#define OMAP2_MCSPI_IRQSTATUS_EOW	BIT(17)
  70
  71#define OMAP2_MCSPI_MODULCTRL_SINGLE	BIT(0)
  72#define OMAP2_MCSPI_MODULCTRL_MS	BIT(2)
  73#define OMAP2_MCSPI_MODULCTRL_STEST	BIT(3)
  74
  75#define OMAP2_MCSPI_CHCONF_PHA		BIT(0)
  76#define OMAP2_MCSPI_CHCONF_POL		BIT(1)
  77#define OMAP2_MCSPI_CHCONF_CLKD_MASK	(0x0f << 2)
  78#define OMAP2_MCSPI_CHCONF_EPOL		BIT(6)
  79#define OMAP2_MCSPI_CHCONF_WL_MASK	(0x1f << 7)
  80#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
  81#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
  82#define OMAP2_MCSPI_CHCONF_TRM_MASK	(0x03 << 12)
  83#define OMAP2_MCSPI_CHCONF_DMAW		BIT(14)
  84#define OMAP2_MCSPI_CHCONF_DMAR		BIT(15)
  85#define OMAP2_MCSPI_CHCONF_DPE0		BIT(16)
  86#define OMAP2_MCSPI_CHCONF_DPE1		BIT(17)
  87#define OMAP2_MCSPI_CHCONF_IS		BIT(18)
  88#define OMAP2_MCSPI_CHCONF_TURBO	BIT(19)
  89#define OMAP2_MCSPI_CHCONF_FORCE	BIT(20)
  90#define OMAP2_MCSPI_CHCONF_FFET		BIT(27)
  91#define OMAP2_MCSPI_CHCONF_FFER		BIT(28)
  92#define OMAP2_MCSPI_CHCONF_CLKG		BIT(29)
  93
  94#define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
  95#define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
  96#define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
  97#define OMAP2_MCSPI_CHSTAT_TXFFE	BIT(3)
  98
  99#define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
 100#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK	(0xff << 8)
 101
 102#define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
 103
 104/* We have 2 DMA channels per CS, one for RX and one for TX */
 105struct omap2_mcspi_dma {
 106	struct dma_chan *dma_tx;
 107	struct dma_chan *dma_rx;
 108
 109	int dma_tx_sync_dev;
 110	int dma_rx_sync_dev;
 111
 112	struct completion dma_tx_completion;
 113	struct completion dma_rx_completion;
 114
 115	char dma_rx_ch_name[14];
 116	char dma_tx_ch_name[14];
 117};
 118
 119/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 120 * cache operations; better heuristics consider wordsize and bitrate.
 121 */
 122#define DMA_MIN_BYTES			160
 123
 124
 125/*
 126 * Used for context save and restore, structure members to be updated whenever
 127 * corresponding registers are modified.
 128 */
 129struct omap2_mcspi_regs {
 130	u32 modulctrl;
 131	u32 wakeupenable;
 132	struct list_head cs;
 133};
 134
 135struct omap2_mcspi {
 
 136	struct spi_master	*master;
 137	/* Virtual base address of the controller */
 138	void __iomem		*base;
 139	unsigned long		phys;
 140	/* SPI1 has 4 channels, while SPI2 has 2 */
 141	struct omap2_mcspi_dma	*dma_channels;
 142	struct device		*dev;
 143	struct omap2_mcspi_regs ctx;
 144	int			fifo_depth;
 
 145	unsigned int		pin_dir:1;
 
 146};
 147
 148struct omap2_mcspi_cs {
 149	void __iomem		*base;
 150	unsigned long		phys;
 151	int			word_len;
 
 152	struct list_head	node;
 153	/* Context save and restore shadow register */
 154	u32			chconf0, chctrl0;
 155};
 156
 157static inline void mcspi_write_reg(struct spi_master *master,
 158		int idx, u32 val)
 159{
 160	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 161
 162	writel_relaxed(val, mcspi->base + idx);
 163}
 164
 165static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 166{
 167	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 168
 169	return readl_relaxed(mcspi->base + idx);
 170}
 171
 172static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 173		int idx, u32 val)
 174{
 175	struct omap2_mcspi_cs	*cs = spi->controller_state;
 176
 177	writel_relaxed(val, cs->base +  idx);
 178}
 179
 180static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 181{
 182	struct omap2_mcspi_cs	*cs = spi->controller_state;
 183
 184	return readl_relaxed(cs->base + idx);
 185}
 186
 187static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 188{
 189	struct omap2_mcspi_cs *cs = spi->controller_state;
 190
 191	return cs->chconf0;
 192}
 193
 194static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 195{
 196	struct omap2_mcspi_cs *cs = spi->controller_state;
 197
 198	cs->chconf0 = val;
 199	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 200	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 201}
 202
 203static inline int mcspi_bytes_per_word(int word_len)
 204{
 205	if (word_len <= 8)
 206		return 1;
 207	else if (word_len <= 16)
 208		return 2;
 209	else /* word_len <= 32 */
 210		return 4;
 211}
 212
 213static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 214		int is_read, int enable)
 215{
 216	u32 l, rw;
 217
 218	l = mcspi_cached_chconf0(spi);
 219
 220	if (is_read) /* 1 is read, 0 write */
 221		rw = OMAP2_MCSPI_CHCONF_DMAR;
 222	else
 223		rw = OMAP2_MCSPI_CHCONF_DMAW;
 224
 225	if (enable)
 226		l |= rw;
 227	else
 228		l &= ~rw;
 229
 230	mcspi_write_chconf0(spi, l);
 231}
 232
 233static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 234{
 235	struct omap2_mcspi_cs *cs = spi->controller_state;
 236	u32 l;
 237
 238	l = cs->chctrl0;
 239	if (enable)
 240		l |= OMAP2_MCSPI_CHCTRL_EN;
 241	else
 242		l &= ~OMAP2_MCSPI_CHCTRL_EN;
 243	cs->chctrl0 = l;
 244	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 245	/* Flash post-writes */
 246	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 247}
 248
 249static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 250{
 
 251	u32 l;
 252
 253	l = mcspi_cached_chconf0(spi);
 254	if (cs_active)
 255		l |= OMAP2_MCSPI_CHCONF_FORCE;
 256	else
 257		l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 258
 259	mcspi_write_chconf0(spi, l);
 
 
 260}
 261
 262static void omap2_mcspi_set_master_mode(struct spi_master *master)
 263{
 264	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
 265	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 266	u32 l;
 267
 268	/*
 269	 * Setup when switching from (reset default) slave mode
 270	 * to single-channel master mode
 271	 */
 272	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 273	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
 274	l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 
 
 
 
 
 275	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 276
 277	ctx->modulctrl = l;
 278}
 279
 280static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 281				struct spi_transfer *t, int enable)
 282{
 283	struct spi_master *master = spi->master;
 284	struct omap2_mcspi_cs *cs = spi->controller_state;
 285	struct omap2_mcspi *mcspi;
 286	unsigned int wcnt;
 287	int max_fifo_depth, fifo_depth, bytes_per_word;
 288	u32 chconf, xferlevel;
 289
 290	mcspi = spi_master_get_devdata(master);
 291
 292	chconf = mcspi_cached_chconf0(spi);
 293	if (enable) {
 294		bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 295		if (t->len % bytes_per_word != 0)
 296			goto disable_fifo;
 297
 298		if (t->rx_buf != NULL && t->tx_buf != NULL)
 299			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 300		else
 301			max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 302
 303		fifo_depth = gcd(t->len, max_fifo_depth);
 304		if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
 305			goto disable_fifo;
 306
 307		wcnt = t->len / bytes_per_word;
 308		if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 309			goto disable_fifo;
 310
 311		xferlevel = wcnt << 16;
 312		if (t->rx_buf != NULL) {
 313			chconf |= OMAP2_MCSPI_CHCONF_FFER;
 314			xferlevel |= (fifo_depth - 1) << 8;
 315		}
 
 316		if (t->tx_buf != NULL) {
 317			chconf |= OMAP2_MCSPI_CHCONF_FFET;
 318			xferlevel |= fifo_depth - 1;
 319		}
 320
 321		mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 322		mcspi_write_chconf0(spi, chconf);
 323		mcspi->fifo_depth = fifo_depth;
 324
 325		return;
 326	}
 327
 328disable_fifo:
 329	if (t->rx_buf != NULL)
 330		chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 331	else
 
 332		chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 333
 334	mcspi_write_chconf0(spi, chconf);
 335	mcspi->fifo_depth = 0;
 336}
 337
 338static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 339{
 340	struct spi_master	*spi_cntrl = mcspi->master;
 341	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 342	struct omap2_mcspi_cs	*cs;
 343
 344	/* McSPI: context restore */
 345	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
 346	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
 347
 348	list_for_each_entry(cs, &ctx->cs, node)
 349		writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 350}
 351
 352static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 353{
 354	unsigned long timeout;
 355
 356	timeout = jiffies + msecs_to_jiffies(1000);
 357	while (!(readl_relaxed(reg) & bit)) {
 358		if (time_after(jiffies, timeout)) {
 359			if (!(readl_relaxed(reg) & bit))
 360				return -ETIMEDOUT;
 361			else
 362				return 0;
 363		}
 364		cpu_relax();
 365	}
 366	return 0;
 367}
 368
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 369static void omap2_mcspi_rx_callback(void *data)
 370{
 371	struct spi_device *spi = data;
 372	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 373	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 374
 375	/* We must disable the DMA RX request */
 376	omap2_mcspi_set_dma_req(spi, 1, 0);
 377
 378	complete(&mcspi_dma->dma_rx_completion);
 379}
 380
 381static void omap2_mcspi_tx_callback(void *data)
 382{
 383	struct spi_device *spi = data;
 384	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 385	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 386
 387	/* We must disable the DMA TX request */
 388	omap2_mcspi_set_dma_req(spi, 0, 0);
 389
 390	complete(&mcspi_dma->dma_tx_completion);
 391}
 392
 393static void omap2_mcspi_tx_dma(struct spi_device *spi,
 394				struct spi_transfer *xfer,
 395				struct dma_slave_config cfg)
 396{
 397	struct omap2_mcspi	*mcspi;
 398	struct omap2_mcspi_dma  *mcspi_dma;
 399	unsigned int		count;
 400
 401	mcspi = spi_master_get_devdata(spi->master);
 402	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 403	count = xfer->len;
 404
 405	if (mcspi_dma->dma_tx) {
 406		struct dma_async_tx_descriptor *tx;
 407		struct scatterlist sg;
 408
 409		dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 410
 411		sg_init_table(&sg, 1);
 412		sg_dma_address(&sg) = xfer->tx_dma;
 413		sg_dma_len(&sg) = xfer->len;
 414
 415		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
 416		DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 417		if (tx) {
 418			tx->callback = omap2_mcspi_tx_callback;
 419			tx->callback_param = spi;
 420			dmaengine_submit(tx);
 421		} else {
 422			/* FIXME: fall back to PIO? */
 423		}
 424	}
 425	dma_async_issue_pending(mcspi_dma->dma_tx);
 426	omap2_mcspi_set_dma_req(spi, 0, 1);
 427
 428}
 429
 430static unsigned
 431omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 432				struct dma_slave_config cfg,
 433				unsigned es)
 434{
 435	struct omap2_mcspi	*mcspi;
 436	struct omap2_mcspi_dma  *mcspi_dma;
 437	unsigned int		count, dma_count;
 
 
 
 438	u32			l;
 439	int			elements = 0;
 440	int			word_len, element_count;
 441	struct omap2_mcspi_cs	*cs = spi->controller_state;
 
 
 
 442	mcspi = spi_master_get_devdata(spi->master);
 443	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 444	count = xfer->len;
 445	dma_count = xfer->len;
 446
 
 
 
 
 
 447	if (mcspi->fifo_depth == 0)
 448		dma_count -= es;
 449
 450	word_len = cs->word_len;
 451	l = mcspi_cached_chconf0(spi);
 452
 453	if (word_len <= 8)
 454		element_count = count;
 455	else if (word_len <= 16)
 456		element_count = count >> 1;
 457	else /* word_len <= 32 */
 458		element_count = count >> 2;
 459
 460	if (mcspi_dma->dma_rx) {
 461		struct dma_async_tx_descriptor *tx;
 462		struct scatterlist sg;
 463
 464		dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 465
 466		if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 467			dma_count -= es;
 468
 469		sg_init_table(&sg, 1);
 470		sg_dma_address(&sg) = xfer->rx_dma;
 471		sg_dma_len(&sg) = dma_count;
 472
 473		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
 474				DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
 475				DMA_CTRL_ACK);
 476		if (tx) {
 477			tx->callback = omap2_mcspi_rx_callback;
 478			tx->callback_param = spi;
 479			dmaengine_submit(tx);
 480		} else {
 481				/* FIXME: fall back to PIO? */
 482		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 483	}
 484
 485	dma_async_issue_pending(mcspi_dma->dma_rx);
 486	omap2_mcspi_set_dma_req(spi, 1, 1);
 487
 488	wait_for_completion(&mcspi_dma->dma_rx_completion);
 489	dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
 490			 DMA_FROM_DEVICE);
 
 
 
 
 
 
 491
 492	if (mcspi->fifo_depth > 0)
 493		return count;
 494
 
 
 
 
 495	omap2_mcspi_set_enable(spi, 0);
 496
 497	elements = element_count - 1;
 498
 499	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 500		elements--;
 501
 502		if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 503				   & OMAP2_MCSPI_CHSTAT_RXS)) {
 504			u32 w;
 505
 506			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 507			if (word_len <= 8)
 508				((u8 *)xfer->rx_buf)[elements++] = w;
 509			else if (word_len <= 16)
 510				((u16 *)xfer->rx_buf)[elements++] = w;
 511			else /* word_len <= 32 */
 512				((u32 *)xfer->rx_buf)[elements++] = w;
 513		} else {
 514			int bytes_per_word = mcspi_bytes_per_word(word_len);
 515			dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 516			count -= (bytes_per_word << 1);
 517			omap2_mcspi_set_enable(spi, 1);
 518			return count;
 519		}
 520	}
 521	if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 522				& OMAP2_MCSPI_CHSTAT_RXS)) {
 523		u32 w;
 524
 525		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 526		if (word_len <= 8)
 527			((u8 *)xfer->rx_buf)[elements] = w;
 528		else if (word_len <= 16)
 529			((u16 *)xfer->rx_buf)[elements] = w;
 530		else /* word_len <= 32 */
 531			((u32 *)xfer->rx_buf)[elements] = w;
 532	} else {
 533		dev_err(&spi->dev, "DMA RX last word empty\n");
 534		count -= mcspi_bytes_per_word(word_len);
 535	}
 536	omap2_mcspi_set_enable(spi, 1);
 537	return count;
 538}
 539
 540static unsigned
 541omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 542{
 543	struct omap2_mcspi	*mcspi;
 544	struct omap2_mcspi_cs	*cs = spi->controller_state;
 545	struct omap2_mcspi_dma  *mcspi_dma;
 546	unsigned int		count;
 547	u32			l;
 548	u8			*rx;
 549	const u8		*tx;
 550	struct dma_slave_config	cfg;
 551	enum dma_slave_buswidth width;
 552	unsigned es;
 553	u32			burst;
 554	void __iomem		*chstat_reg;
 555	void __iomem            *irqstat_reg;
 556	int			wait_res;
 557
 558	mcspi = spi_master_get_devdata(spi->master);
 559	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 560	l = mcspi_cached_chconf0(spi);
 561
 562
 563	if (cs->word_len <= 8) {
 564		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 565		es = 1;
 566	} else if (cs->word_len <= 16) {
 567		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 568		es = 2;
 569	} else {
 570		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 571		es = 4;
 572	}
 573
 574	count = xfer->len;
 575	burst = 1;
 576
 577	if (mcspi->fifo_depth > 0) {
 578		if (count > mcspi->fifo_depth)
 579			burst = mcspi->fifo_depth / es;
 580		else
 581			burst = count / es;
 582	}
 583
 584	memset(&cfg, 0, sizeof(cfg));
 585	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 586	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 587	cfg.src_addr_width = width;
 588	cfg.dst_addr_width = width;
 589	cfg.src_maxburst = burst;
 590	cfg.dst_maxburst = burst;
 591
 592	rx = xfer->rx_buf;
 593	tx = xfer->tx_buf;
 594
 595	if (tx != NULL)
 
 
 
 
 
 
 
 
 
 596		omap2_mcspi_tx_dma(spi, xfer, cfg);
 
 597
 598	if (rx != NULL)
 599		count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 600
 601	if (tx != NULL) {
 602		wait_for_completion(&mcspi_dma->dma_tx_completion);
 603		dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len,
 604				 DMA_TO_DEVICE);
 
 
 
 
 
 
 
 
 
 
 
 605
 606		if (mcspi->fifo_depth > 0) {
 607			irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 608
 609			if (mcspi_wait_for_reg_bit(irqstat_reg,
 610						OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 611				dev_err(&spi->dev, "EOW timed out\n");
 612
 613			mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 614					OMAP2_MCSPI_IRQSTATUS_EOW);
 615		}
 616
 617		/* for TX_ONLY mode, be sure all words have shifted out */
 618		if (rx == NULL) {
 619			chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 620			if (mcspi->fifo_depth > 0) {
 621				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 622						OMAP2_MCSPI_CHSTAT_TXFFE);
 623				if (wait_res < 0)
 624					dev_err(&spi->dev, "TXFFE timed out\n");
 625			} else {
 626				wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 627						OMAP2_MCSPI_CHSTAT_TXS);
 628				if (wait_res < 0)
 629					dev_err(&spi->dev, "TXS timed out\n");
 630			}
 631			if (wait_res >= 0 &&
 632				(mcspi_wait_for_reg_bit(chstat_reg,
 633					OMAP2_MCSPI_CHSTAT_EOT) < 0))
 634				dev_err(&spi->dev, "EOT timed out\n");
 635		}
 636	}
 637	return count;
 638}
 639
 640static unsigned
 641omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 642{
 643	struct omap2_mcspi	*mcspi;
 644	struct omap2_mcspi_cs	*cs = spi->controller_state;
 645	unsigned int		count, c;
 646	u32			l;
 647	void __iomem		*base = cs->base;
 648	void __iomem		*tx_reg;
 649	void __iomem		*rx_reg;
 650	void __iomem		*chstat_reg;
 651	int			word_len;
 652
 653	mcspi = spi_master_get_devdata(spi->master);
 654	count = xfer->len;
 655	c = count;
 656	word_len = cs->word_len;
 657
 658	l = mcspi_cached_chconf0(spi);
 659
 660	/* We store the pre-calculated register addresses on stack to speed
 661	 * up the transfer loop. */
 662	tx_reg		= base + OMAP2_MCSPI_TX0;
 663	rx_reg		= base + OMAP2_MCSPI_RX0;
 664	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
 665
 666	if (c < (word_len>>3))
 667		return 0;
 668
 669	if (word_len <= 8) {
 670		u8		*rx;
 671		const u8	*tx;
 672
 673		rx = xfer->rx_buf;
 674		tx = xfer->tx_buf;
 675
 676		do {
 677			c -= 1;
 678			if (tx != NULL) {
 679				if (mcspi_wait_for_reg_bit(chstat_reg,
 680						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 681					dev_err(&spi->dev, "TXS timed out\n");
 682					goto out;
 683				}
 684				dev_vdbg(&spi->dev, "write-%d %02x\n",
 685						word_len, *tx);
 686				writel_relaxed(*tx++, tx_reg);
 687			}
 688			if (rx != NULL) {
 689				if (mcspi_wait_for_reg_bit(chstat_reg,
 690						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 691					dev_err(&spi->dev, "RXS timed out\n");
 692					goto out;
 693				}
 694
 695				if (c == 1 && tx == NULL &&
 696				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 697					omap2_mcspi_set_enable(spi, 0);
 698					*rx++ = readl_relaxed(rx_reg);
 699					dev_vdbg(&spi->dev, "read-%d %02x\n",
 700						    word_len, *(rx - 1));
 701					if (mcspi_wait_for_reg_bit(chstat_reg,
 702						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 703						dev_err(&spi->dev,
 704							"RXS timed out\n");
 705						goto out;
 706					}
 707					c = 0;
 708				} else if (c == 0 && tx == NULL) {
 709					omap2_mcspi_set_enable(spi, 0);
 710				}
 711
 712				*rx++ = readl_relaxed(rx_reg);
 713				dev_vdbg(&spi->dev, "read-%d %02x\n",
 714						word_len, *(rx - 1));
 715			}
 
 
 716		} while (c);
 717	} else if (word_len <= 16) {
 718		u16		*rx;
 719		const u16	*tx;
 720
 721		rx = xfer->rx_buf;
 722		tx = xfer->tx_buf;
 723		do {
 724			c -= 2;
 725			if (tx != NULL) {
 726				if (mcspi_wait_for_reg_bit(chstat_reg,
 727						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 728					dev_err(&spi->dev, "TXS timed out\n");
 729					goto out;
 730				}
 731				dev_vdbg(&spi->dev, "write-%d %04x\n",
 732						word_len, *tx);
 733				writel_relaxed(*tx++, tx_reg);
 734			}
 735			if (rx != NULL) {
 736				if (mcspi_wait_for_reg_bit(chstat_reg,
 737						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 738					dev_err(&spi->dev, "RXS timed out\n");
 739					goto out;
 740				}
 741
 742				if (c == 2 && tx == NULL &&
 743				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 744					omap2_mcspi_set_enable(spi, 0);
 745					*rx++ = readl_relaxed(rx_reg);
 746					dev_vdbg(&spi->dev, "read-%d %04x\n",
 747						    word_len, *(rx - 1));
 748					if (mcspi_wait_for_reg_bit(chstat_reg,
 749						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 750						dev_err(&spi->dev,
 751							"RXS timed out\n");
 752						goto out;
 753					}
 754					c = 0;
 755				} else if (c == 0 && tx == NULL) {
 756					omap2_mcspi_set_enable(spi, 0);
 757				}
 758
 759				*rx++ = readl_relaxed(rx_reg);
 760				dev_vdbg(&spi->dev, "read-%d %04x\n",
 761						word_len, *(rx - 1));
 762			}
 
 
 763		} while (c >= 2);
 764	} else if (word_len <= 32) {
 765		u32		*rx;
 766		const u32	*tx;
 767
 768		rx = xfer->rx_buf;
 769		tx = xfer->tx_buf;
 770		do {
 771			c -= 4;
 772			if (tx != NULL) {
 773				if (mcspi_wait_for_reg_bit(chstat_reg,
 774						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 775					dev_err(&spi->dev, "TXS timed out\n");
 776					goto out;
 777				}
 778				dev_vdbg(&spi->dev, "write-%d %08x\n",
 779						word_len, *tx);
 780				writel_relaxed(*tx++, tx_reg);
 781			}
 782			if (rx != NULL) {
 783				if (mcspi_wait_for_reg_bit(chstat_reg,
 784						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 785					dev_err(&spi->dev, "RXS timed out\n");
 786					goto out;
 787				}
 788
 789				if (c == 4 && tx == NULL &&
 790				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 791					omap2_mcspi_set_enable(spi, 0);
 792					*rx++ = readl_relaxed(rx_reg);
 793					dev_vdbg(&spi->dev, "read-%d %08x\n",
 794						    word_len, *(rx - 1));
 795					if (mcspi_wait_for_reg_bit(chstat_reg,
 796						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 797						dev_err(&spi->dev,
 798							"RXS timed out\n");
 799						goto out;
 800					}
 801					c = 0;
 802				} else if (c == 0 && tx == NULL) {
 803					omap2_mcspi_set_enable(spi, 0);
 804				}
 805
 806				*rx++ = readl_relaxed(rx_reg);
 807				dev_vdbg(&spi->dev, "read-%d %08x\n",
 808						word_len, *(rx - 1));
 809			}
 
 
 810		} while (c >= 4);
 811	}
 812
 813	/* for TX_ONLY mode, be sure all words have shifted out */
 814	if (xfer->rx_buf == NULL) {
 815		if (mcspi_wait_for_reg_bit(chstat_reg,
 816				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 817			dev_err(&spi->dev, "TXS timed out\n");
 818		} else if (mcspi_wait_for_reg_bit(chstat_reg,
 819				OMAP2_MCSPI_CHSTAT_EOT) < 0)
 820			dev_err(&spi->dev, "EOT timed out\n");
 821
 822		/* disable chan to purge rx datas received in TX_ONLY transfer,
 823		 * otherwise these rx datas will affect the direct following
 824		 * RX_ONLY transfer.
 825		 */
 826		omap2_mcspi_set_enable(spi, 0);
 827	}
 828out:
 829	omap2_mcspi_set_enable(spi, 1);
 830	return count - c;
 831}
 832
 833static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 834{
 835	u32 div;
 836
 837	for (div = 0; div < 15; div++)
 838		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 839			return div;
 840
 841	return 15;
 842}
 843
 844/* called only when no transfer is active to this device */
 845static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 846		struct spi_transfer *t)
 847{
 848	struct omap2_mcspi_cs *cs = spi->controller_state;
 849	struct omap2_mcspi *mcspi;
 850	struct spi_master *spi_cntrl;
 851	u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 852	u8 word_len = spi->bits_per_word;
 853	u32 speed_hz = spi->max_speed_hz;
 854
 855	mcspi = spi_master_get_devdata(spi->master);
 856	spi_cntrl = mcspi->master;
 857
 858	if (t != NULL && t->bits_per_word)
 859		word_len = t->bits_per_word;
 860
 861	cs->word_len = word_len;
 862
 863	if (t && t->speed_hz)
 864		speed_hz = t->speed_hz;
 865
 866	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 867	if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 868		clkd = omap2_mcspi_calc_divisor(speed_hz);
 869		speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 870		clkg = 0;
 871	} else {
 872		div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 873		speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 874		clkd = (div - 1) & 0xf;
 875		extclk = (div - 1) >> 4;
 876		clkg = OMAP2_MCSPI_CHCONF_CLKG;
 877	}
 878
 879	l = mcspi_cached_chconf0(spi);
 880
 881	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 882	 * REVISIT: this controller could support SPI_3WIRE mode.
 883	 */
 884	if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 885		l &= ~OMAP2_MCSPI_CHCONF_IS;
 886		l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 887		l |= OMAP2_MCSPI_CHCONF_DPE0;
 888	} else {
 889		l |= OMAP2_MCSPI_CHCONF_IS;
 890		l |= OMAP2_MCSPI_CHCONF_DPE1;
 891		l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 892	}
 893
 894	/* wordlength */
 895	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 896	l |= (word_len - 1) << 7;
 897
 898	/* set chipselect polarity; manage with FORCE */
 899	if (!(spi->mode & SPI_CS_HIGH))
 900		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
 901	else
 902		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 903
 904	/* set clock divisor */
 905	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 906	l |= clkd << 2;
 907
 908	/* set clock granularity */
 909	l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 910	l |= clkg;
 911	if (clkg) {
 912		cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 913		cs->chctrl0 |= extclk << 8;
 914		mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 915	}
 916
 917	/* set SPI mode 0..3 */
 918	if (spi->mode & SPI_CPOL)
 919		l |= OMAP2_MCSPI_CHCONF_POL;
 920	else
 921		l &= ~OMAP2_MCSPI_CHCONF_POL;
 922	if (spi->mode & SPI_CPHA)
 923		l |= OMAP2_MCSPI_CHCONF_PHA;
 924	else
 925		l &= ~OMAP2_MCSPI_CHCONF_PHA;
 926
 927	mcspi_write_chconf0(spi, l);
 928
 
 
 929	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 930			speed_hz,
 931			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
 932			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
 933
 934	return 0;
 935}
 936
 937/*
 938 * Note that we currently allow DMA only if we get a channel
 939 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 940 */
 941static int omap2_mcspi_request_dma(struct spi_device *spi)
 
 942{
 943	struct spi_master	*master = spi->master;
 944	struct omap2_mcspi	*mcspi;
 945	struct omap2_mcspi_dma	*mcspi_dma;
 946	dma_cap_mask_t mask;
 947	unsigned sig;
 
 
 
 
 948
 949	mcspi = spi_master_get_devdata(master);
 950	mcspi_dma = mcspi->dma_channels + spi->chip_select;
 
 
 
 
 
 
 951
 952	init_completion(&mcspi_dma->dma_rx_completion);
 953	init_completion(&mcspi_dma->dma_tx_completion);
 954
 955	dma_cap_zero(mask);
 956	dma_cap_set(DMA_SLAVE, mask);
 957	sig = mcspi_dma->dma_rx_sync_dev;
 958
 959	mcspi_dma->dma_rx =
 960		dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 961						 &sig, &master->dev,
 962						 mcspi_dma->dma_rx_ch_name);
 963	if (!mcspi_dma->dma_rx)
 964		goto no_dma;
 965
 966	sig = mcspi_dma->dma_tx_sync_dev;
 967	mcspi_dma->dma_tx =
 968		dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 969						 &sig, &master->dev,
 970						 mcspi_dma->dma_tx_ch_name);
 971
 972	if (!mcspi_dma->dma_tx) {
 973		dma_release_channel(mcspi_dma->dma_rx);
 974		mcspi_dma->dma_rx = NULL;
 975		goto no_dma;
 
 
 
 
 
 
 
 976	}
 
 
 
 
 
 977
 978	return 0;
 
 
 
 979
 980no_dma:
 981	dev_warn(&spi->dev, "not using DMA for McSPI\n");
 982	return -EAGAIN;
 983}
 984
 985static int omap2_mcspi_setup(struct spi_device *spi)
 986{
 
 987	int			ret;
 988	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
 989	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 990	struct omap2_mcspi_dma	*mcspi_dma;
 991	struct omap2_mcspi_cs	*cs = spi->controller_state;
 992
 993	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 994
 995	if (!cs) {
 996		cs = kzalloc(sizeof *cs, GFP_KERNEL);
 997		if (!cs)
 998			return -ENOMEM;
 999		cs->base = mcspi->base + spi->chip_select * 0x14;
1000		cs->phys = mcspi->phys + spi->chip_select * 0x14;
 
1001		cs->chconf0 = 0;
1002		cs->chctrl0 = 0;
1003		spi->controller_state = cs;
1004		/* Link this to context save list */
1005		list_add_tail(&cs->node, &ctx->cs);
 
1006	}
1007
1008	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1009		ret = omap2_mcspi_request_dma(spi);
1010		if (ret < 0 && ret != -EAGAIN)
1011			return ret;
1012	}
1013
1014	ret = pm_runtime_get_sync(mcspi->dev);
1015	if (ret < 0)
1016		return ret;
 
1017
1018	ret = omap2_mcspi_setup_transfer(spi, NULL);
 
 
 
1019	pm_runtime_mark_last_busy(mcspi->dev);
1020	pm_runtime_put_autosuspend(mcspi->dev);
1021
1022	return ret;
1023}
1024
1025static void omap2_mcspi_cleanup(struct spi_device *spi)
1026{
1027	struct omap2_mcspi	*mcspi;
1028	struct omap2_mcspi_dma	*mcspi_dma;
1029	struct omap2_mcspi_cs	*cs;
1030
1031	mcspi = spi_master_get_devdata(spi->master);
 
 
1032
1033	if (spi->controller_state) {
1034		/* Unlink controller state from context save list */
1035		cs = spi->controller_state;
1036		list_del(&cs->node);
1037
1038		kfree(cs);
1039	}
1040
1041	if (spi->chip_select < spi->master->num_chipselect) {
1042		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 
 
1043
1044		if (mcspi_dma->dma_rx) {
1045			dma_release_channel(mcspi_dma->dma_rx);
1046			mcspi_dma->dma_rx = NULL;
1047		}
1048		if (mcspi_dma->dma_tx) {
1049			dma_release_channel(mcspi_dma->dma_tx);
1050			mcspi_dma->dma_tx = NULL;
1051		}
1052	}
1053}
1054
1055static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
 
 
1056{
1057
1058	/* We only enable one channel at a time -- the one whose message is
1059	 * -- although this controller would gladly
1060	 * arbitrate among multiple channels.  This corresponds to "single
1061	 * channel" master mode.  As a side effect, we need to manage the
1062	 * chipselect with the FORCE bit ... CS != channel enable.
1063	 */
1064
1065	struct spi_device		*spi;
1066	struct spi_transfer		*t = NULL;
1067	struct spi_master		*master;
1068	struct omap2_mcspi_dma		*mcspi_dma;
1069	int				cs_active = 0;
1070	struct omap2_mcspi_cs		*cs;
1071	struct omap2_mcspi_device_config *cd;
1072	int				par_override = 0;
1073	int				status = 0;
1074	u32				chconf;
1075
1076	spi = m->spi;
1077	master = spi->master;
1078	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1079	cs = spi->controller_state;
1080	cd = spi->controller_data;
1081
 
 
 
 
 
 
 
 
 
 
1082	omap2_mcspi_set_enable(spi, 0);
1083	list_for_each_entry(t, &m->transfers, transfer_list) {
1084		if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
1085			status = -EINVAL;
1086			break;
1087		}
1088		if (par_override ||
1089		    (t->speed_hz != spi->max_speed_hz) ||
1090		    (t->bits_per_word != spi->bits_per_word)) {
1091			par_override = 1;
1092			status = omap2_mcspi_setup_transfer(spi, t);
1093			if (status < 0)
1094				break;
1095			if (t->speed_hz == spi->max_speed_hz &&
1096			    t->bits_per_word == spi->bits_per_word)
1097				par_override = 0;
1098		}
1099		if (cd && cd->cs_per_word) {
1100			chconf = mcspi->ctx.modulctrl;
1101			chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1102			mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1103			mcspi->ctx.modulctrl =
1104				mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1105		}
1106
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1107
1108		if (!cs_active) {
1109			omap2_mcspi_force_cs(spi, 1);
1110			cs_active = 1;
1111		}
1112
1113		chconf = mcspi_cached_chconf0(spi);
1114		chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1115		chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
 
 
 
 
 
 
 
1116
1117		if (t->tx_buf == NULL)
1118			chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1119		else if (t->rx_buf == NULL)
1120			chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1121
1122		if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1123			/* Turbo mode is for more than one word */
1124			if (t->len > ((cs->word_len + 7) >> 3))
1125				chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1126		}
1127
1128		mcspi_write_chconf0(spi, chconf);
 
1129
1130		if (t->len) {
1131			unsigned	count;
 
 
1132
1133			if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1134			    (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1135				omap2_mcspi_set_fifo(spi, t, 1);
1136
1137			omap2_mcspi_set_enable(spi, 1);
 
 
 
1138
1139			/* RX_ONLY mode needs dummy data in TX reg */
1140			if (t->tx_buf == NULL)
1141				writel_relaxed(0, cs->base
1142						+ OMAP2_MCSPI_TX0);
1143
1144			if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1145			    (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1146				count = omap2_mcspi_txrx_dma(spi, t);
1147			else
1148				count = omap2_mcspi_txrx_pio(spi, t);
1149			m->actual_length += count;
1150
1151			if (count != t->len) {
1152				status = -EIO;
1153				break;
1154			}
1155		}
 
1156
1157		if (t->delay_usecs)
1158			udelay(t->delay_usecs);
1159
1160		/* ignore the "leave it on after last xfer" hint */
1161		if (t->cs_change) {
1162			omap2_mcspi_force_cs(spi, 0);
1163			cs_active = 0;
1164		}
1165
1166		omap2_mcspi_set_enable(spi, 0);
1167
1168		if (mcspi->fifo_depth > 0)
1169			omap2_mcspi_set_fifo(spi, t, 0);
1170	}
1171	/* Restore defaults if they were overriden */
1172	if (par_override) {
1173		par_override = 0;
1174		status = omap2_mcspi_setup_transfer(spi, NULL);
1175	}
1176
1177	if (cs_active)
1178		omap2_mcspi_force_cs(spi, 0);
1179
1180	if (cd && cd->cs_per_word) {
1181		chconf = mcspi->ctx.modulctrl;
1182		chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1183		mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1184		mcspi->ctx.modulctrl =
1185			mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1186	}
1187
1188	omap2_mcspi_set_enable(spi, 0);
1189
 
 
 
1190	if (mcspi->fifo_depth > 0 && t)
1191		omap2_mcspi_set_fifo(spi, t, 0);
1192
1193	m->status = status;
1194}
1195
1196static int omap2_mcspi_transfer_one_message(struct spi_master *master,
1197		struct spi_message *m)
1198{
1199	struct spi_device	*spi;
1200	struct omap2_mcspi	*mcspi;
1201	struct omap2_mcspi_dma	*mcspi_dma;
1202	struct spi_transfer	*t;
1203
1204	spi = m->spi;
1205	mcspi = spi_master_get_devdata(master);
1206	mcspi_dma = mcspi->dma_channels + spi->chip_select;
1207	m->actual_length = 0;
1208	m->status = 0;
1209
1210	list_for_each_entry(t, &m->transfers, transfer_list) {
1211		const void	*tx_buf = t->tx_buf;
1212		void		*rx_buf = t->rx_buf;
1213		unsigned	len = t->len;
1214
1215		if ((len && !(rx_buf || tx_buf))) {
1216			dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1217					t->speed_hz,
1218					len,
1219					tx_buf ? "tx" : "",
1220					rx_buf ? "rx" : "",
1221					t->bits_per_word);
1222			return -EINVAL;
1223		}
1224
1225		if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1226			continue;
1227
1228		if (mcspi_dma->dma_tx && tx_buf != NULL) {
1229			t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1230					len, DMA_TO_DEVICE);
1231			if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1232				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1233						'T', len);
1234				return -EINVAL;
1235			}
1236		}
1237		if (mcspi_dma->dma_rx && rx_buf != NULL) {
1238			t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1239					DMA_FROM_DEVICE);
1240			if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1241				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1242						'R', len);
1243				if (tx_buf != NULL)
1244					dma_unmap_single(mcspi->dev, t->tx_dma,
1245							len, DMA_TO_DEVICE);
1246				return -EINVAL;
1247			}
1248		}
1249	}
1250
1251	omap2_mcspi_work(mcspi, m);
1252	spi_finalize_current_message(master);
1253	return 0;
1254}
1255
1256static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1257{
1258	struct spi_master	*master = mcspi->master;
1259	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1260	int			ret = 0;
1261
1262	ret = pm_runtime_get_sync(mcspi->dev);
1263	if (ret < 0)
1264		return ret;
1265
1266	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1267			OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1268	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1269
1270	omap2_mcspi_set_master_mode(master);
1271	pm_runtime_mark_last_busy(mcspi->dev);
1272	pm_runtime_put_autosuspend(mcspi->dev);
1273	return 0;
1274}
1275
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1276static int omap_mcspi_runtime_resume(struct device *dev)
1277{
1278	struct omap2_mcspi	*mcspi;
1279	struct spi_master	*master;
 
 
 
 
 
 
 
 
 
 
 
1280
1281	master = dev_get_drvdata(dev);
1282	mcspi = spi_master_get_devdata(master);
1283	omap2_mcspi_restore_ctx(mcspi);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1284
1285	return 0;
1286}
1287
1288static struct omap2_mcspi_platform_config omap2_pdata = {
1289	.regs_offset = 0,
1290};
1291
1292static struct omap2_mcspi_platform_config omap4_pdata = {
1293	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1294};
1295
 
 
 
 
 
1296static const struct of_device_id omap_mcspi_of_match[] = {
1297	{
1298		.compatible = "ti,omap2-mcspi",
1299		.data = &omap2_pdata,
1300	},
1301	{
1302		.compatible = "ti,omap4-mcspi",
1303		.data = &omap4_pdata,
1304	},
 
 
 
 
1305	{ },
1306};
1307MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1308
1309static int omap2_mcspi_probe(struct platform_device *pdev)
1310{
1311	struct spi_master	*master;
1312	const struct omap2_mcspi_platform_config *pdata;
1313	struct omap2_mcspi	*mcspi;
1314	struct resource		*r;
1315	int			status = 0, i;
1316	u32			regs_offset = 0;
1317	static int		bus_num = 1;
1318	struct device_node	*node = pdev->dev.of_node;
1319	const struct of_device_id *match;
1320
1321	master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1322	if (master == NULL) {
1323		dev_dbg(&pdev->dev, "master allocation failed\n");
 
 
1324		return -ENOMEM;
1325	}
1326
1327	/* the spi->mode bits understood by this driver: */
1328	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1329	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1330	master->setup = omap2_mcspi_setup;
1331	master->auto_runtime_pm = true;
1332	master->transfer_one_message = omap2_mcspi_transfer_one_message;
 
 
 
1333	master->cleanup = omap2_mcspi_cleanup;
 
1334	master->dev.of_node = node;
1335	master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1336	master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
 
1337
1338	platform_set_drvdata(pdev, master);
1339
1340	mcspi = spi_master_get_devdata(master);
1341	mcspi->master = master;
1342
1343	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1344	if (match) {
1345		u32 num_cs = 1; /* default number of chipselect */
1346		pdata = match->data;
1347
1348		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1349		master->num_chipselect = num_cs;
1350		master->bus_num = bus_num++;
1351		if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1352			mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1353	} else {
1354		pdata = dev_get_platdata(&pdev->dev);
1355		master->num_chipselect = pdata->num_cs;
1356		if (pdev->id != -1)
1357			master->bus_num = pdev->id;
1358		mcspi->pin_dir = pdata->pin_dir;
1359	}
1360	regs_offset = pdata->regs_offset;
 
 
 
 
1361
1362	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1363	if (r == NULL) {
1364		status = -ENODEV;
1365		goto free_master;
1366	}
1367
1368	r->start += regs_offset;
1369	r->end += regs_offset;
1370	mcspi->phys = r->start;
1371
1372	mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1373	if (IS_ERR(mcspi->base)) {
1374		status = PTR_ERR(mcspi->base);
1375		goto free_master;
1376	}
 
 
1377
1378	mcspi->dev = &pdev->dev;
1379
1380	INIT_LIST_HEAD(&mcspi->ctx.cs);
1381
1382	mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1383					   sizeof(struct omap2_mcspi_dma),
1384					   GFP_KERNEL);
1385	if (mcspi->dma_channels == NULL) {
1386		status = -ENOMEM;
1387		goto free_master;
1388	}
1389
1390	for (i = 0; i < master->num_chipselect; i++) {
1391		char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1392		char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1393		struct resource *dma_res;
1394
1395		sprintf(dma_rx_ch_name, "rx%d", i);
1396		if (!pdev->dev.of_node) {
1397			dma_res =
1398				platform_get_resource_byname(pdev,
1399							     IORESOURCE_DMA,
1400							     dma_rx_ch_name);
1401			if (!dma_res) {
1402				dev_dbg(&pdev->dev,
1403					"cannot get DMA RX channel\n");
1404				status = -ENODEV;
1405				break;
1406			}
1407
1408			mcspi->dma_channels[i].dma_rx_sync_dev =
1409				dma_res->start;
1410		}
1411		sprintf(dma_tx_ch_name, "tx%d", i);
1412		if (!pdev->dev.of_node) {
1413			dma_res =
1414				platform_get_resource_byname(pdev,
1415							     IORESOURCE_DMA,
1416							     dma_tx_ch_name);
1417			if (!dma_res) {
1418				dev_dbg(&pdev->dev,
1419					"cannot get DMA TX channel\n");
1420				status = -ENODEV;
1421				break;
1422			}
1423
1424			mcspi->dma_channels[i].dma_tx_sync_dev =
1425				dma_res->start;
1426		}
 
1427	}
1428
1429	if (status < 0)
 
 
 
 
1430		goto free_master;
 
1431
1432	pm_runtime_use_autosuspend(&pdev->dev);
1433	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1434	pm_runtime_enable(&pdev->dev);
1435
1436	status = omap2_mcspi_master_setup(mcspi);
1437	if (status < 0)
1438		goto disable_pm;
1439
1440	status = devm_spi_register_master(&pdev->dev, master);
1441	if (status < 0)
1442		goto disable_pm;
1443
1444	return status;
1445
1446disable_pm:
 
 
1447	pm_runtime_disable(&pdev->dev);
1448free_master:
 
1449	spi_master_put(master);
1450	return status;
1451}
1452
1453static int omap2_mcspi_remove(struct platform_device *pdev)
1454{
1455	struct spi_master *master = platform_get_drvdata(pdev);
1456	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1457
 
 
 
1458	pm_runtime_put_sync(mcspi->dev);
1459	pm_runtime_disable(&pdev->dev);
1460
1461	return 0;
1462}
1463
1464/* work with hotplug and coldplug */
1465MODULE_ALIAS("platform:omap2_mcspi");
1466
1467#ifdef	CONFIG_SUSPEND
1468/*
1469 * When SPI wake up from off-mode, CS is in activate state. If it was in
1470 * unactive state when driver was suspend, then force it to unactive state at
1471 * wake up.
1472 */
1473static int omap2_mcspi_resume(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
1474{
1475	struct spi_master	*master = dev_get_drvdata(dev);
1476	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1477	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1478	struct omap2_mcspi_cs	*cs;
 
 
 
 
1479
1480	pm_runtime_get_sync(mcspi->dev);
1481	list_for_each_entry(cs, &ctx->cs, node) {
1482		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1483			/*
1484			 * We need to toggle CS state for OMAP take this
1485			 * change in account.
1486			 */
1487			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1488			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1489			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1490			writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1491		}
1492	}
1493	pm_runtime_mark_last_busy(mcspi->dev);
1494	pm_runtime_put_autosuspend(mcspi->dev);
1495	return 0;
1496}
1497#else
1498#define	omap2_mcspi_resume	NULL
1499#endif
1500
1501static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1502	.resume = omap2_mcspi_resume,
1503	.runtime_resume	= omap_mcspi_runtime_resume,
 
 
1504};
1505
1506static struct platform_driver omap2_mcspi_driver = {
1507	.driver = {
1508		.name =		"omap2_mcspi",
1509		.owner =	THIS_MODULE,
1510		.pm =		&omap2_mcspi_pm_ops,
1511		.of_match_table = omap_mcspi_of_match,
1512	},
1513	.probe =	omap2_mcspi_probe,
1514	.remove =	omap2_mcspi_remove,
1515};
1516
1517module_platform_driver(omap2_mcspi_driver);
1518MODULE_LICENSE("GPL");