Linux Audio

Check our new training course

Loading...
v6.2
   1// SPDX-License-Identifier: GPL-2.0+
   2// Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3// Copyright (C) 2008 Juergen Beisert
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   4
   5#include <linux/clk.h>
   6#include <linux/completion.h>
   7#include <linux/delay.h>
   8#include <linux/dmaengine.h>
   9#include <linux/dma-mapping.h>
  10#include <linux/err.h>
 
  11#include <linux/interrupt.h>
  12#include <linux/io.h>
  13#include <linux/irq.h>
  14#include <linux/kernel.h>
  15#include <linux/module.h>
  16#include <linux/pinctrl/consumer.h>
  17#include <linux/platform_device.h>
  18#include <linux/pm_runtime.h>
  19#include <linux/slab.h>
  20#include <linux/spi/spi.h>
 
  21#include <linux/types.h>
  22#include <linux/of.h>
  23#include <linux/of_device.h>
  24#include <linux/property.h>
  25
  26#include <linux/dma/imx-dma.h>
 
  27
  28#define DRIVER_NAME "spi_imx"
  29
  30static bool use_dma = true;
  31module_param(use_dma, bool, 0644);
  32MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
  33
  34/* define polling limits */
  35static unsigned int polling_limit_us = 30;
  36module_param(polling_limit_us, uint, 0664);
  37MODULE_PARM_DESC(polling_limit_us,
  38		 "time in us to run a transfer in polling mode\n");
  39
  40#define MXC_RPM_TIMEOUT		2000 /* 2000ms */
  41
  42#define MXC_CSPIRXDATA		0x00
  43#define MXC_CSPITXDATA		0x04
  44#define MXC_CSPICTRL		0x08
  45#define MXC_CSPIINT		0x0c
  46#define MXC_RESET		0x1c
  47
  48/* generic defines to abstract from the different register layouts */
  49#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
  50#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
  51#define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
  52
  53/* The maximum bytes that a sdma BD can transfer. */
  54#define MAX_SDMA_BD_BYTES (1 << 15)
  55#define MX51_ECSPI_CTRL_MAX_BURST	512
  56/* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
  57#define MX53_MAX_TRANSFER_BYTES		512
 
 
 
  58
  59enum spi_imx_devtype {
  60	IMX1_CSPI,
  61	IMX21_CSPI,
  62	IMX27_CSPI,
  63	IMX31_CSPI,
  64	IMX35_CSPI,	/* CSPI on all i.mx except above */
  65	IMX51_ECSPI,	/* ECSPI on i.mx51 */
  66	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
  67};
  68
  69struct spi_imx_data;
  70
  71struct spi_imx_devtype_data {
  72	void (*intctrl)(struct spi_imx_data *spi_imx, int enable);
  73	int (*prepare_message)(struct spi_imx_data *spi_imx, struct spi_message *msg);
  74	int (*prepare_transfer)(struct spi_imx_data *spi_imx, struct spi_device *spi);
  75	void (*trigger)(struct spi_imx_data *spi_imx);
  76	int (*rx_available)(struct spi_imx_data *spi_imx);
  77	void (*reset)(struct spi_imx_data *spi_imx);
  78	void (*setup_wml)(struct spi_imx_data *spi_imx);
  79	void (*disable)(struct spi_imx_data *spi_imx);
  80	bool has_dmamode;
  81	bool has_slavemode;
  82	unsigned int fifo_size;
  83	bool dynamic_burst;
  84	/*
  85	 * ERR009165 fixed or not:
  86	 * https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf
  87	 */
  88	bool tx_glitch_fixed;
  89	enum spi_imx_devtype devtype;
  90};
  91
  92struct spi_imx_data {
  93	struct spi_controller *controller;
  94	struct device *dev;
  95
  96	struct completion xfer_done;
  97	void __iomem *base;
  98	unsigned long base_phys;
  99
 100	struct clk *clk_per;
 101	struct clk *clk_ipg;
 102	unsigned long spi_clk;
 103	unsigned int spi_bus_clk;
 104
 105	unsigned int bits_per_word;
 106	unsigned int spi_drctl;
 107
 108	unsigned int count, remainder;
 109	void (*tx)(struct spi_imx_data *spi_imx);
 110	void (*rx)(struct spi_imx_data *spi_imx);
 111	void *rx_buf;
 112	const void *tx_buf;
 113	unsigned int txfifo; /* number of words pushed in tx FIFO */
 114	unsigned int dynamic_burst;
 115	bool rx_only;
 116
 117	/* Slave mode */
 118	bool slave_mode;
 119	bool slave_aborted;
 120	unsigned int slave_burst;
 121
 122	/* DMA */
 123	bool usedma;
 124	u32 wml;
 125	struct completion dma_rx_completion;
 126	struct completion dma_tx_completion;
 127
 128	const struct spi_imx_devtype_data *devtype_data;
 
 129};
 130
 131static inline int is_imx27_cspi(struct spi_imx_data *d)
 132{
 133	return d->devtype_data->devtype == IMX27_CSPI;
 134}
 135
 136static inline int is_imx35_cspi(struct spi_imx_data *d)
 137{
 138	return d->devtype_data->devtype == IMX35_CSPI;
 139}
 140
 141static inline int is_imx51_ecspi(struct spi_imx_data *d)
 142{
 143	return d->devtype_data->devtype == IMX51_ECSPI;
 144}
 145
 146static inline int is_imx53_ecspi(struct spi_imx_data *d)
 147{
 148	return d->devtype_data->devtype == IMX53_ECSPI;
 149}
 150
 151#define MXC_SPI_BUF_RX(type)						\
 152static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 153{									\
 154	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 155									\
 156	if (spi_imx->rx_buf) {						\
 157		*(type *)spi_imx->rx_buf = val;				\
 158		spi_imx->rx_buf += sizeof(type);			\
 159	}								\
 160									\
 161	spi_imx->remainder -= sizeof(type);				\
 162}
 163
 164#define MXC_SPI_BUF_TX(type)						\
 165static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 166{									\
 167	type val = 0;							\
 168									\
 169	if (spi_imx->tx_buf) {						\
 170		val = *(type *)spi_imx->tx_buf;				\
 171		spi_imx->tx_buf += sizeof(type);			\
 172	}								\
 173									\
 174	spi_imx->count -= sizeof(type);					\
 175									\
 176	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 177}
 178
 179MXC_SPI_BUF_RX(u8)
 180MXC_SPI_BUF_TX(u8)
 181MXC_SPI_BUF_RX(u16)
 182MXC_SPI_BUF_TX(u16)
 183MXC_SPI_BUF_RX(u32)
 184MXC_SPI_BUF_TX(u32)
 185
 186/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 187 * (which is currently not the case in this driver)
 188 */
 189static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 190	256, 384, 512, 768, 1024};
 191
 192/* MX21, MX27 */
 193static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 194		unsigned int fspi, unsigned int max, unsigned int *fres)
 195{
 196	int i;
 197
 198	for (i = 2; i < max; i++)
 199		if (fspi * mxc_clkdivs[i] >= fin)
 200			break;
 201
 202	*fres = fin / mxc_clkdivs[i];
 203	return i;
 204}
 205
 206/* MX1, MX31, MX35, MX51 CSPI */
 207static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 208		unsigned int fspi, unsigned int *fres)
 209{
 210	int i, div = 4;
 211
 212	for (i = 0; i < 7; i++) {
 213		if (fspi * div >= fin)
 214			goto out;
 215		div <<= 1;
 216	}
 217
 218out:
 219	*fres = fin / div;
 220	return i;
 221}
 222
 223static int spi_imx_bytes_per_word(const int bits_per_word)
 224{
 225	if (bits_per_word <= 8)
 226		return 1;
 227	else if (bits_per_word <= 16)
 228		return 2;
 229	else
 230		return 4;
 231}
 232
 233static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device *spi,
 234			 struct spi_transfer *transfer)
 235{
 236	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
 
 237
 238	if (!use_dma || controller->fallback)
 239		return false;
 240
 241	if (!controller->dma_rx)
 242		return false;
 243
 244	if (spi_imx->slave_mode)
 
 
 
 
 
 
 245		return false;
 246
 247	if (transfer->len < spi_imx->devtype_data->fifo_size)
 248		return false;
 249
 250	spi_imx->dynamic_burst = 0;
 
 251
 252	return true;
 253}
 254
 255#define MX51_ECSPI_CTRL		0x08
 256#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
 257#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 258#define MX51_ECSPI_CTRL_SMC		(1 << 3)
 259#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 260#define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
 261#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
 262#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 263#define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
 264#define MX51_ECSPI_CTRL_BL_OFFSET	20
 265#define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
 266
 267#define MX51_ECSPI_CONFIG	0x0c
 268#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
 269#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
 270#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
 271#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
 272#define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
 273
 274#define MX51_ECSPI_INT		0x10
 275#define MX51_ECSPI_INT_TEEN		(1 <<  0)
 276#define MX51_ECSPI_INT_RREN		(1 <<  3)
 277#define MX51_ECSPI_INT_RDREN		(1 <<  4)
 278
 279#define MX51_ECSPI_DMA		0x14
 280#define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
 281#define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
 282#define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
 283
 284#define MX51_ECSPI_DMA_TEDEN		(1 << 7)
 285#define MX51_ECSPI_DMA_RXDEN		(1 << 23)
 286#define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
 287
 288#define MX51_ECSPI_STAT		0x18
 289#define MX51_ECSPI_STAT_RR		(1 <<  3)
 290
 291#define MX51_ECSPI_TESTREG	0x20
 292#define MX51_ECSPI_TESTREG_LBC	BIT(31)
 293
 294static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
 295{
 296	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
 297
 298	if (spi_imx->rx_buf) {
 299#ifdef __LITTLE_ENDIAN
 300		unsigned int bytes_per_word;
 301
 302		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 303		if (bytes_per_word == 1)
 304			swab32s(&val);
 305		else if (bytes_per_word == 2)
 306			swahw32s(&val);
 307#endif
 308		*(u32 *)spi_imx->rx_buf = val;
 309		spi_imx->rx_buf += sizeof(u32);
 310	}
 311
 312	spi_imx->remainder -= sizeof(u32);
 313}
 314
 315static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
 316{
 317	int unaligned;
 318	u32 val;
 319
 320	unaligned = spi_imx->remainder % 4;
 321
 322	if (!unaligned) {
 323		spi_imx_buf_rx_swap_u32(spi_imx);
 324		return;
 325	}
 326
 327	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 328		spi_imx_buf_rx_u16(spi_imx);
 329		return;
 330	}
 331
 332	val = readl(spi_imx->base + MXC_CSPIRXDATA);
 333
 334	while (unaligned--) {
 335		if (spi_imx->rx_buf) {
 336			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
 337			spi_imx->rx_buf++;
 338		}
 339		spi_imx->remainder--;
 340	}
 341}
 342
 343static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
 344{
 345	u32 val = 0;
 346#ifdef __LITTLE_ENDIAN
 347	unsigned int bytes_per_word;
 348#endif
 349
 350	if (spi_imx->tx_buf) {
 351		val = *(u32 *)spi_imx->tx_buf;
 352		spi_imx->tx_buf += sizeof(u32);
 353	}
 354
 355	spi_imx->count -= sizeof(u32);
 356#ifdef __LITTLE_ENDIAN
 357	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 358
 359	if (bytes_per_word == 1)
 360		swab32s(&val);
 361	else if (bytes_per_word == 2)
 362		swahw32s(&val);
 363#endif
 364	writel(val, spi_imx->base + MXC_CSPITXDATA);
 365}
 366
 367static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
 368{
 369	int unaligned;
 370	u32 val = 0;
 371
 372	unaligned = spi_imx->count % 4;
 373
 374	if (!unaligned) {
 375		spi_imx_buf_tx_swap_u32(spi_imx);
 376		return;
 377	}
 378
 379	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 380		spi_imx_buf_tx_u16(spi_imx);
 381		return;
 382	}
 383
 384	while (unaligned--) {
 385		if (spi_imx->tx_buf) {
 386			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
 387			spi_imx->tx_buf++;
 388		}
 389		spi_imx->count--;
 390	}
 391
 392	writel(val, spi_imx->base + MXC_CSPITXDATA);
 393}
 394
 395static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
 396{
 397	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
 398
 399	if (spi_imx->rx_buf) {
 400		int n_bytes = spi_imx->slave_burst % sizeof(val);
 401
 402		if (!n_bytes)
 403			n_bytes = sizeof(val);
 404
 405		memcpy(spi_imx->rx_buf,
 406		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
 407
 408		spi_imx->rx_buf += n_bytes;
 409		spi_imx->slave_burst -= n_bytes;
 410	}
 411
 412	spi_imx->remainder -= sizeof(u32);
 413}
 414
 415static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
 416{
 417	u32 val = 0;
 418	int n_bytes = spi_imx->count % sizeof(val);
 419
 420	if (!n_bytes)
 421		n_bytes = sizeof(val);
 422
 423	if (spi_imx->tx_buf) {
 424		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
 425		       spi_imx->tx_buf, n_bytes);
 426		val = cpu_to_be32(val);
 427		spi_imx->tx_buf += n_bytes;
 428	}
 429
 430	spi_imx->count -= n_bytes;
 431
 432	writel(val, spi_imx->base + MXC_CSPITXDATA);
 433}
 434
 435/* MX51 eCSPI */
 436static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 437				      unsigned int fspi, unsigned int *fres)
 438{
 439	/*
 440	 * there are two 4-bit dividers, the pre-divider divides by
 441	 * $pre, the post-divider by 2^$post
 442	 */
 443	unsigned int pre, post;
 444	unsigned int fin = spi_imx->spi_clk;
 445
 446	fspi = min(fspi, fin);
 
 447
 448	post = fls(fin) - fls(fspi);
 449	if (fin > fspi << post)
 450		post++;
 451
 452	/* now we have: (fin <= fspi << post) with post being minimal */
 453
 454	post = max(4U, post) - 4;
 455	if (unlikely(post > 0xf)) {
 456		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 457				fspi, fin);
 458		return 0xff;
 459	}
 460
 461	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 462
 463	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 464			__func__, fin, fspi, post, pre);
 465
 466	/* Resulting frequency for the SCLK line. */
 467	*fres = (fin / (pre + 1)) >> post;
 468
 469	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 470		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 471}
 472
 473static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 474{
 475	unsigned int val = 0;
 476
 477	if (enable & MXC_INT_TE)
 478		val |= MX51_ECSPI_INT_TEEN;
 479
 480	if (enable & MXC_INT_RR)
 481		val |= MX51_ECSPI_INT_RREN;
 482
 483	if (enable & MXC_INT_RDR)
 484		val |= MX51_ECSPI_INT_RDREN;
 485
 486	writel(val, spi_imx->base + MX51_ECSPI_INT);
 487}
 488
 489static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 490{
 491	u32 reg;
 492
 493	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 494	reg |= MX51_ECSPI_CTRL_XCH;
 495	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 496}
 497
 498static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
 
 499{
 500	u32 ctrl;
 501
 502	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 503	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
 504	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 505}
 506
 507static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
 508				      struct spi_message *msg)
 509{
 510	struct spi_device *spi = msg->spi;
 511	struct spi_transfer *xfer;
 512	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 513	u32 min_speed_hz = ~0U;
 514	u32 testreg, delay;
 515	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 516	u32 current_cfg = cfg;
 517
 518	/* set Master or Slave mode */
 519	if (spi_imx->slave_mode)
 520		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
 521	else
 522		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 523
 524	/*
 525	 * Enable SPI_RDY handling (falling edge/level triggered).
 
 
 
 
 526	 */
 527	if (spi->mode & SPI_READY)
 528		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
 
 
 
 529
 530	/* set chip select to use */
 531	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
 532
 533	/*
 534	 * The ctrl register must be written first, with the EN bit set other
 535	 * registers must not be written to.
 536	 */
 537	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 538
 539	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 540	if (spi->mode & SPI_LOOP)
 541		testreg |= MX51_ECSPI_TESTREG_LBC;
 542	else
 543		testreg &= ~MX51_ECSPI_TESTREG_LBC;
 544	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
 545
 546	/*
 547	 * eCSPI burst completion by Chip Select signal in Slave mode
 548	 * is not functional for imx53 Soc, config SPI burst completed when
 549	 * BURST_LENGTH + 1 bits are received
 550	 */
 551	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 552		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 553	else
 554		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 555
 556	if (spi->mode & SPI_CPOL) {
 557		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 558		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 559	} else {
 560		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 561		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 562	}
 563
 564	if (spi->mode & SPI_CS_HIGH)
 565		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 566	else
 567		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 568
 569	if (cfg == current_cfg)
 570		return 0;
 
 
 
 
 
 
 
 
 
 
 571
 572	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 573
 574	/*
 575	 * Wait until the changes in the configuration register CONFIGREG
 576	 * propagate into the hardware. It takes exactly one tick of the
 577	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 578	 * effect of the delay it takes for the hardware to apply changes
 579	 * is noticable if the SCLK clock run very slow. In such a case, if
 580	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 581	 * be asserted before the SCLK polarity changes, which would disrupt
 582	 * the SPI communication as the device on the other end would consider
 583	 * the change of SCLK polarity as a clock tick already.
 584	 *
 585	 * Because spi_imx->spi_bus_clk is only set in prepare_message
 586	 * callback, iterate over all the transfers in spi_message, find the
 587	 * one with lowest bus frequency, and use that bus frequency for the
 588	 * delay calculation. In case all transfers have speed_hz == 0, then
 589	 * min_speed_hz is ~0 and the resulting delay is zero.
 590	 */
 591	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
 592		if (!xfer->speed_hz)
 593			continue;
 594		min_speed_hz = min(xfer->speed_hz, min_speed_hz);
 595	}
 596
 597	delay = (2 * 1000000) / min_speed_hz;
 598	if (likely(delay < 10))	/* SCLK is faster than 200 kHz */
 599		udelay(delay);
 600	else			/* SCLK is _very_ slow */
 601		usleep_range(delay, delay + 10);
 602
 603	return 0;
 604}
 605
 606static void mx51_configure_cpha(struct spi_imx_data *spi_imx,
 607				struct spi_device *spi)
 608{
 609	bool cpha = (spi->mode & SPI_CPHA);
 610	bool flip_cpha = (spi->mode & SPI_RX_CPHA_FLIP) && spi_imx->rx_only;
 611	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 612
 613	/* Flip cpha logical value iff flip_cpha */
 614	cpha ^= flip_cpha;
 615
 616	if (cpha)
 617		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 618	else
 619		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 620
 621	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 622}
 623
 624static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
 625				       struct spi_device *spi)
 626{
 627	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 628	u32 clk;
 629
 630	/* Clear BL field and set the right value */
 631	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
 632	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 633		ctrl |= (spi_imx->slave_burst * 8 - 1)
 634			<< MX51_ECSPI_CTRL_BL_OFFSET;
 635	else
 636		ctrl |= (spi_imx->bits_per_word - 1)
 637			<< MX51_ECSPI_CTRL_BL_OFFSET;
 638
 639	/* set clock speed */
 640	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
 641		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
 642	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
 643	spi_imx->spi_bus_clk = clk;
 644
 645	mx51_configure_cpha(spi_imx, spi);
 646
 647	/*
 648	 * ERR009165: work in XHC mode instead of SMC as PIO on the chips
 649	 * before i.mx6ul.
 650	 */
 651	if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
 652		ctrl |= MX51_ECSPI_CTRL_SMC;
 653	else
 654		ctrl &= ~MX51_ECSPI_CTRL_SMC;
 655
 656	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 657
 658	return 0;
 659}
 660
 661static void mx51_setup_wml(struct spi_imx_data *spi_imx)
 662{
 663	u32 tx_wml = 0;
 664
 665	if (spi_imx->devtype_data->tx_glitch_fixed)
 666		tx_wml = spi_imx->wml;
 667	/*
 668	 * Configure the DMA register: setup the watermark
 669	 * and enable DMA request.
 670	 */
 671	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
 672		MX51_ECSPI_DMA_TX_WML(tx_wml) |
 
 673		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 674		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 675		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 
 
 676}
 677
 678static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 679{
 680	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 681}
 682
 683static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 684{
 685	/* drain receive buffer */
 686	while (mx51_ecspi_rx_available(spi_imx))
 687		readl(spi_imx->base + MXC_CSPIRXDATA);
 688}
 689
 690#define MX31_INTREG_TEEN	(1 << 0)
 691#define MX31_INTREG_RREN	(1 << 3)
 692
 693#define MX31_CSPICTRL_ENABLE	(1 << 0)
 694#define MX31_CSPICTRL_MASTER	(1 << 1)
 695#define MX31_CSPICTRL_XCH	(1 << 2)
 696#define MX31_CSPICTRL_SMC	(1 << 3)
 697#define MX31_CSPICTRL_POL	(1 << 4)
 698#define MX31_CSPICTRL_PHA	(1 << 5)
 699#define MX31_CSPICTRL_SSCTL	(1 << 6)
 700#define MX31_CSPICTRL_SSPOL	(1 << 7)
 701#define MX31_CSPICTRL_BC_SHIFT	8
 702#define MX35_CSPICTRL_BL_SHIFT	20
 703#define MX31_CSPICTRL_CS_SHIFT	24
 704#define MX35_CSPICTRL_CS_SHIFT	12
 705#define MX31_CSPICTRL_DR_SHIFT	16
 706
 707#define MX31_CSPI_DMAREG	0x10
 708#define MX31_DMAREG_RH_DEN	(1<<4)
 709#define MX31_DMAREG_TH_DEN	(1<<1)
 710
 711#define MX31_CSPISTATUS		0x14
 712#define MX31_STATUS_RR		(1 << 3)
 713
 714#define MX31_CSPI_TESTREG	0x1C
 715#define MX31_TEST_LBC		(1 << 14)
 716
 717/* These functions also work for the i.MX35, but be aware that
 718 * the i.MX35 has a slightly different register layout for bits
 719 * we do not use here.
 720 */
 721static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 722{
 723	unsigned int val = 0;
 724
 725	if (enable & MXC_INT_TE)
 726		val |= MX31_INTREG_TEEN;
 727	if (enable & MXC_INT_RR)
 728		val |= MX31_INTREG_RREN;
 729
 730	writel(val, spi_imx->base + MXC_CSPIINT);
 731}
 732
 733static void mx31_trigger(struct spi_imx_data *spi_imx)
 734{
 735	unsigned int reg;
 736
 737	reg = readl(spi_imx->base + MXC_CSPICTRL);
 738	reg |= MX31_CSPICTRL_XCH;
 739	writel(reg, spi_imx->base + MXC_CSPICTRL);
 740}
 741
 742static int mx31_prepare_message(struct spi_imx_data *spi_imx,
 743				struct spi_message *msg)
 744{
 745	return 0;
 746}
 747
 748static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
 749				 struct spi_device *spi)
 750{
 751	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 752	unsigned int clk;
 753
 754	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
 755		MX31_CSPICTRL_DR_SHIFT;
 756	spi_imx->spi_bus_clk = clk;
 757
 758	if (is_imx35_cspi(spi_imx)) {
 759		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
 760		reg |= MX31_CSPICTRL_SSCTL;
 761	} else {
 762		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
 763	}
 764
 765	if (spi->mode & SPI_CPHA)
 766		reg |= MX31_CSPICTRL_PHA;
 767	if (spi->mode & SPI_CPOL)
 768		reg |= MX31_CSPICTRL_POL;
 769	if (spi->mode & SPI_CS_HIGH)
 770		reg |= MX31_CSPICTRL_SSPOL;
 771	if (!spi->cs_gpiod)
 772		reg |= (spi->chip_select) <<
 773			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 774						  MX31_CSPICTRL_CS_SHIFT);
 775
 776	if (spi_imx->usedma)
 777		reg |= MX31_CSPICTRL_SMC;
 778
 779	writel(reg, spi_imx->base + MXC_CSPICTRL);
 780
 781	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
 782	if (spi->mode & SPI_LOOP)
 783		reg |= MX31_TEST_LBC;
 784	else
 785		reg &= ~MX31_TEST_LBC;
 786	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 787
 788	if (spi_imx->usedma) {
 789		/*
 790		 * configure DMA requests when RXFIFO is half full and
 791		 * when TXFIFO is half empty
 792		 */
 793		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
 794			spi_imx->base + MX31_CSPI_DMAREG);
 795	}
 796
 797	return 0;
 798}
 799
 800static int mx31_rx_available(struct spi_imx_data *spi_imx)
 801{
 802	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 803}
 804
 805static void mx31_reset(struct spi_imx_data *spi_imx)
 806{
 807	/* drain receive buffer */
 808	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 809		readl(spi_imx->base + MXC_CSPIRXDATA);
 810}
 811
 812#define MX21_INTREG_RR		(1 << 4)
 813#define MX21_INTREG_TEEN	(1 << 9)
 814#define MX21_INTREG_RREN	(1 << 13)
 815
 816#define MX21_CSPICTRL_POL	(1 << 5)
 817#define MX21_CSPICTRL_PHA	(1 << 6)
 818#define MX21_CSPICTRL_SSPOL	(1 << 8)
 819#define MX21_CSPICTRL_XCH	(1 << 9)
 820#define MX21_CSPICTRL_ENABLE	(1 << 10)
 821#define MX21_CSPICTRL_MASTER	(1 << 11)
 822#define MX21_CSPICTRL_DR_SHIFT	14
 823#define MX21_CSPICTRL_CS_SHIFT	19
 824
 825static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 826{
 827	unsigned int val = 0;
 828
 829	if (enable & MXC_INT_TE)
 830		val |= MX21_INTREG_TEEN;
 831	if (enable & MXC_INT_RR)
 832		val |= MX21_INTREG_RREN;
 833
 834	writel(val, spi_imx->base + MXC_CSPIINT);
 835}
 836
 837static void mx21_trigger(struct spi_imx_data *spi_imx)
 838{
 839	unsigned int reg;
 840
 841	reg = readl(spi_imx->base + MXC_CSPICTRL);
 842	reg |= MX21_CSPICTRL_XCH;
 843	writel(reg, spi_imx->base + MXC_CSPICTRL);
 844}
 845
 846static int mx21_prepare_message(struct spi_imx_data *spi_imx,
 847				struct spi_message *msg)
 848{
 849	return 0;
 850}
 851
 852static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
 853				 struct spi_device *spi)
 854{
 855	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 
 856	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 857	unsigned int clk;
 858
 859	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
 860		<< MX21_CSPICTRL_DR_SHIFT;
 861	spi_imx->spi_bus_clk = clk;
 862
 863	reg |= spi_imx->bits_per_word - 1;
 864
 865	if (spi->mode & SPI_CPHA)
 866		reg |= MX21_CSPICTRL_PHA;
 867	if (spi->mode & SPI_CPOL)
 868		reg |= MX21_CSPICTRL_POL;
 869	if (spi->mode & SPI_CS_HIGH)
 870		reg |= MX21_CSPICTRL_SSPOL;
 871	if (!spi->cs_gpiod)
 872		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
 873
 874	writel(reg, spi_imx->base + MXC_CSPICTRL);
 875
 876	return 0;
 877}
 878
 879static int mx21_rx_available(struct spi_imx_data *spi_imx)
 880{
 881	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 882}
 883
 884static void mx21_reset(struct spi_imx_data *spi_imx)
 885{
 886	writel(1, spi_imx->base + MXC_RESET);
 887}
 888
 889#define MX1_INTREG_RR		(1 << 3)
 890#define MX1_INTREG_TEEN		(1 << 8)
 891#define MX1_INTREG_RREN		(1 << 11)
 892
 893#define MX1_CSPICTRL_POL	(1 << 4)
 894#define MX1_CSPICTRL_PHA	(1 << 5)
 895#define MX1_CSPICTRL_XCH	(1 << 8)
 896#define MX1_CSPICTRL_ENABLE	(1 << 9)
 897#define MX1_CSPICTRL_MASTER	(1 << 10)
 898#define MX1_CSPICTRL_DR_SHIFT	13
 899
 900static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 901{
 902	unsigned int val = 0;
 903
 904	if (enable & MXC_INT_TE)
 905		val |= MX1_INTREG_TEEN;
 906	if (enable & MXC_INT_RR)
 907		val |= MX1_INTREG_RREN;
 908
 909	writel(val, spi_imx->base + MXC_CSPIINT);
 910}
 911
 912static void mx1_trigger(struct spi_imx_data *spi_imx)
 913{
 914	unsigned int reg;
 915
 916	reg = readl(spi_imx->base + MXC_CSPICTRL);
 917	reg |= MX1_CSPICTRL_XCH;
 918	writel(reg, spi_imx->base + MXC_CSPICTRL);
 919}
 920
 921static int mx1_prepare_message(struct spi_imx_data *spi_imx,
 922			       struct spi_message *msg)
 923{
 924	return 0;
 925}
 926
 927static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
 928				struct spi_device *spi)
 929{
 930	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 931	unsigned int clk;
 932
 933	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
 934		MX1_CSPICTRL_DR_SHIFT;
 935	spi_imx->spi_bus_clk = clk;
 936
 937	reg |= spi_imx->bits_per_word - 1;
 938
 939	if (spi->mode & SPI_CPHA)
 940		reg |= MX1_CSPICTRL_PHA;
 941	if (spi->mode & SPI_CPOL)
 942		reg |= MX1_CSPICTRL_POL;
 943
 944	writel(reg, spi_imx->base + MXC_CSPICTRL);
 945
 946	return 0;
 947}
 948
 949static int mx1_rx_available(struct spi_imx_data *spi_imx)
 950{
 951	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 952}
 953
 954static void mx1_reset(struct spi_imx_data *spi_imx)
 955{
 956	writel(1, spi_imx->base + MXC_RESET);
 957}
 958
 959static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 960	.intctrl = mx1_intctrl,
 961	.prepare_message = mx1_prepare_message,
 962	.prepare_transfer = mx1_prepare_transfer,
 963	.trigger = mx1_trigger,
 964	.rx_available = mx1_rx_available,
 965	.reset = mx1_reset,
 966	.fifo_size = 8,
 967	.has_dmamode = false,
 968	.dynamic_burst = false,
 969	.has_slavemode = false,
 970	.devtype = IMX1_CSPI,
 971};
 972
 973static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 974	.intctrl = mx21_intctrl,
 975	.prepare_message = mx21_prepare_message,
 976	.prepare_transfer = mx21_prepare_transfer,
 977	.trigger = mx21_trigger,
 978	.rx_available = mx21_rx_available,
 979	.reset = mx21_reset,
 980	.fifo_size = 8,
 981	.has_dmamode = false,
 982	.dynamic_burst = false,
 983	.has_slavemode = false,
 984	.devtype = IMX21_CSPI,
 985};
 986
 987static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 988	/* i.mx27 cspi shares the functions with i.mx21 one */
 989	.intctrl = mx21_intctrl,
 990	.prepare_message = mx21_prepare_message,
 991	.prepare_transfer = mx21_prepare_transfer,
 992	.trigger = mx21_trigger,
 993	.rx_available = mx21_rx_available,
 994	.reset = mx21_reset,
 995	.fifo_size = 8,
 996	.has_dmamode = false,
 997	.dynamic_burst = false,
 998	.has_slavemode = false,
 999	.devtype = IMX27_CSPI,
1000};
1001
1002static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
1003	.intctrl = mx31_intctrl,
1004	.prepare_message = mx31_prepare_message,
1005	.prepare_transfer = mx31_prepare_transfer,
1006	.trigger = mx31_trigger,
1007	.rx_available = mx31_rx_available,
1008	.reset = mx31_reset,
1009	.fifo_size = 8,
1010	.has_dmamode = false,
1011	.dynamic_burst = false,
1012	.has_slavemode = false,
1013	.devtype = IMX31_CSPI,
1014};
1015
1016static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
1017	/* i.mx35 and later cspi shares the functions with i.mx31 one */
1018	.intctrl = mx31_intctrl,
1019	.prepare_message = mx31_prepare_message,
1020	.prepare_transfer = mx31_prepare_transfer,
1021	.trigger = mx31_trigger,
1022	.rx_available = mx31_rx_available,
1023	.reset = mx31_reset,
1024	.fifo_size = 8,
1025	.has_dmamode = true,
1026	.dynamic_burst = false,
1027	.has_slavemode = false,
1028	.devtype = IMX35_CSPI,
1029};
1030
1031static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
1032	.intctrl = mx51_ecspi_intctrl,
1033	.prepare_message = mx51_ecspi_prepare_message,
1034	.prepare_transfer = mx51_ecspi_prepare_transfer,
1035	.trigger = mx51_ecspi_trigger,
1036	.rx_available = mx51_ecspi_rx_available,
1037	.reset = mx51_ecspi_reset,
1038	.setup_wml = mx51_setup_wml,
1039	.fifo_size = 64,
1040	.has_dmamode = true,
1041	.dynamic_burst = true,
1042	.has_slavemode = true,
1043	.disable = mx51_ecspi_disable,
1044	.devtype = IMX51_ECSPI,
1045};
1046
1047static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1048	.intctrl = mx51_ecspi_intctrl,
1049	.prepare_message = mx51_ecspi_prepare_message,
1050	.prepare_transfer = mx51_ecspi_prepare_transfer,
1051	.trigger = mx51_ecspi_trigger,
1052	.rx_available = mx51_ecspi_rx_available,
1053	.reset = mx51_ecspi_reset,
1054	.fifo_size = 64,
1055	.has_dmamode = true,
1056	.has_slavemode = true,
1057	.disable = mx51_ecspi_disable,
1058	.devtype = IMX53_ECSPI,
1059};
1060
1061static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
1062	.intctrl = mx51_ecspi_intctrl,
1063	.prepare_message = mx51_ecspi_prepare_message,
1064	.prepare_transfer = mx51_ecspi_prepare_transfer,
1065	.trigger = mx51_ecspi_trigger,
1066	.rx_available = mx51_ecspi_rx_available,
1067	.reset = mx51_ecspi_reset,
1068	.setup_wml = mx51_setup_wml,
1069	.fifo_size = 64,
1070	.has_dmamode = true,
1071	.dynamic_burst = true,
1072	.has_slavemode = true,
1073	.tx_glitch_fixed = true,
1074	.disable = mx51_ecspi_disable,
1075	.devtype = IMX51_ECSPI,
1076};
1077
1078static const struct of_device_id spi_imx_dt_ids[] = {
1079	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1080	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1081	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1082	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1083	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1084	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1085	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1086	{ .compatible = "fsl,imx6ul-ecspi", .data = &imx6ul_ecspi_devtype_data, },
1087	{ /* sentinel */ }
1088};
1089MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1090
1091static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1092{
1093	u32 ctrl;
 
 
 
1094
1095	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1096	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1097	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1098	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1099}
1100
1101static void spi_imx_push(struct spi_imx_data *spi_imx)
1102{
1103	unsigned int burst_len;
1104
1105	/*
1106	 * Reload the FIFO when the remaining bytes to be transferred in the
1107	 * current burst is 0. This only applies when bits_per_word is a
1108	 * multiple of 8.
1109	 */
1110	if (!spi_imx->remainder) {
1111		if (spi_imx->dynamic_burst) {
1112
1113			/* We need to deal unaligned data first */
1114			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1115
1116			if (!burst_len)
1117				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1118
1119			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1120
1121			spi_imx->remainder = burst_len;
1122		} else {
1123			spi_imx->remainder = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1124		}
1125	}
1126
1127	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1128		if (!spi_imx->count)
1129			break;
1130		if (spi_imx->dynamic_burst &&
1131		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder, 4))
1132			break;
1133		spi_imx->tx(spi_imx);
1134		spi_imx->txfifo++;
1135	}
1136
1137	if (!spi_imx->slave_mode)
1138		spi_imx->devtype_data->trigger(spi_imx);
1139}
1140
1141static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1142{
1143	struct spi_imx_data *spi_imx = dev_id;
1144
1145	while (spi_imx->txfifo &&
1146	       spi_imx->devtype_data->rx_available(spi_imx)) {
1147		spi_imx->rx(spi_imx);
1148		spi_imx->txfifo--;
1149	}
1150
1151	if (spi_imx->count) {
1152		spi_imx_push(spi_imx);
1153		return IRQ_HANDLED;
1154	}
1155
1156	if (spi_imx->txfifo) {
1157		/* No data left to push, but still waiting for rx data,
1158		 * enable receive data available interrupt.
1159		 */
1160		spi_imx->devtype_data->intctrl(
1161				spi_imx, MXC_INT_RR);
1162		return IRQ_HANDLED;
1163	}
1164
1165	spi_imx->devtype_data->intctrl(spi_imx, 0);
1166	complete(&spi_imx->xfer_done);
1167
1168	return IRQ_HANDLED;
1169}
1170
1171static int spi_imx_dma_configure(struct spi_controller *controller)
 
1172{
1173	int ret;
1174	enum dma_slave_buswidth buswidth;
1175	struct dma_slave_config rx = {}, tx = {};
1176	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
 
 
 
 
1177
1178	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1179	case 4:
1180		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1181		break;
1182	case 2:
1183		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1184		break;
1185	case 1:
1186		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1187		break;
1188	default:
1189		return -EINVAL;
1190	}
1191
1192	tx.direction = DMA_MEM_TO_DEV;
1193	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1194	tx.dst_addr_width = buswidth;
1195	tx.dst_maxburst = spi_imx->wml;
1196	ret = dmaengine_slave_config(controller->dma_tx, &tx);
1197	if (ret) {
1198		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1199		return ret;
1200	}
1201
1202	rx.direction = DMA_DEV_TO_MEM;
1203	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1204	rx.src_addr_width = buswidth;
1205	rx.src_maxburst = spi_imx->wml;
1206	ret = dmaengine_slave_config(controller->dma_rx, &rx);
1207	if (ret) {
1208		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1209		return ret;
1210	}
1211
 
 
1212	return 0;
1213}
1214
1215static int spi_imx_setupxfer(struct spi_device *spi,
1216				 struct spi_transfer *t)
1217{
1218	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1219
1220	if (!t)
1221		return 0;
1222
1223	if (!t->speed_hz) {
1224		if (!spi->max_speed_hz) {
1225			dev_err(&spi->dev, "no speed_hz provided!\n");
1226			return -EINVAL;
1227		}
1228		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1229		spi_imx->spi_bus_clk = spi->max_speed_hz;
1230	} else
1231		spi_imx->spi_bus_clk = t->speed_hz;
1232
1233	spi_imx->bits_per_word = t->bits_per_word;
1234
1235	/*
1236	 * Initialize the functions for transfer. To transfer non byte-aligned
1237	 * words, we have to use multiple word-size bursts, we can't use
1238	 * dynamic_burst in that case.
1239	 */
1240	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1241	    !(spi->mode & SPI_CS_WORD) &&
1242	    (spi_imx->bits_per_word == 8 ||
1243	    spi_imx->bits_per_word == 16 ||
1244	    spi_imx->bits_per_word == 32)) {
1245
1246		spi_imx->rx = spi_imx_buf_rx_swap;
1247		spi_imx->tx = spi_imx_buf_tx_swap;
1248		spi_imx->dynamic_burst = 1;
1249
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1250	} else {
1251		if (spi_imx->bits_per_word <= 8) {
1252			spi_imx->rx = spi_imx_buf_rx_u8;
1253			spi_imx->tx = spi_imx_buf_tx_u8;
1254		} else if (spi_imx->bits_per_word <= 16) {
1255			spi_imx->rx = spi_imx_buf_rx_u16;
1256			spi_imx->tx = spi_imx_buf_tx_u16;
1257		} else {
1258			spi_imx->rx = spi_imx_buf_rx_u32;
1259			spi_imx->tx = spi_imx_buf_tx_u32;
1260		}
1261		spi_imx->dynamic_burst = 0;
1262	}
1263
1264	if (spi_imx_can_dma(spi_imx->controller, spi, t))
1265		spi_imx->usedma = true;
1266	else
1267		spi_imx->usedma = false;
1268
1269	spi_imx->rx_only = ((t->tx_buf == NULL)
1270			|| (t->tx_buf == spi->controller->dummy_tx));
1271
1272	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1273		spi_imx->rx = mx53_ecspi_rx_slave;
1274		spi_imx->tx = mx53_ecspi_tx_slave;
1275		spi_imx->slave_burst = t->len;
1276	}
1277
1278	spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
1279
1280	return 0;
1281}
1282
1283static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1284{
1285	struct spi_controller *controller = spi_imx->controller;
1286
1287	if (controller->dma_rx) {
1288		dma_release_channel(controller->dma_rx);
1289		controller->dma_rx = NULL;
1290	}
1291
1292	if (controller->dma_tx) {
1293		dma_release_channel(controller->dma_tx);
1294		controller->dma_tx = NULL;
1295	}
1296}
1297
1298static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1299			     struct spi_controller *controller)
1300{
1301	int ret;
1302
1303	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
 
 
 
 
1304
1305	/* Prepare for TX DMA: */
1306	controller->dma_tx = dma_request_chan(dev, "tx");
1307	if (IS_ERR(controller->dma_tx)) {
1308		ret = PTR_ERR(controller->dma_tx);
1309		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1310		controller->dma_tx = NULL;
1311		goto err;
1312	}
1313
1314	/* Prepare for RX : */
1315	controller->dma_rx = dma_request_chan(dev, "rx");
1316	if (IS_ERR(controller->dma_rx)) {
1317		ret = PTR_ERR(controller->dma_rx);
1318		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1319		controller->dma_rx = NULL;
1320		goto err;
1321	}
1322
 
 
1323	init_completion(&spi_imx->dma_rx_completion);
1324	init_completion(&spi_imx->dma_tx_completion);
1325	controller->can_dma = spi_imx_can_dma;
1326	controller->max_dma_len = MAX_SDMA_BD_BYTES;
1327	spi_imx->controller->flags = SPI_CONTROLLER_MUST_RX |
1328					 SPI_CONTROLLER_MUST_TX;
1329
1330	return 0;
1331err:
1332	spi_imx_sdma_exit(spi_imx);
1333	return ret;
1334}
1335
1336static void spi_imx_dma_rx_callback(void *cookie)
1337{
1338	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1339
1340	complete(&spi_imx->dma_rx_completion);
1341}
1342
1343static void spi_imx_dma_tx_callback(void *cookie)
1344{
1345	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1346
1347	complete(&spi_imx->dma_tx_completion);
1348}
1349
1350static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1351{
1352	unsigned long timeout = 0;
1353
1354	/* Time with actual data transfer and CS change delay related to HW */
1355	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1356
1357	/* Add extra second for scheduler related activities */
1358	timeout += 1;
1359
1360	/* Double calculated timeout */
1361	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1362}
1363
1364static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1365				struct spi_transfer *transfer)
1366{
1367	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1368	unsigned long transfer_timeout;
1369	unsigned long timeout;
1370	struct spi_controller *controller = spi_imx->controller;
1371	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1372	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1373	unsigned int bytes_per_word, i;
1374	int ret;
1375
1376	/* Get the right burst length from the last sg to ensure no tail data */
1377	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1378	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1379		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1380			break;
1381	}
1382	/* Use 1 as wml in case no available burst length got */
1383	if (i == 0)
1384		i = 1;
1385
1386	spi_imx->wml =  i;
1387
1388	ret = spi_imx_dma_configure(controller);
1389	if (ret)
1390		goto dma_failure_no_start;
1391
1392	if (!spi_imx->devtype_data->setup_wml) {
1393		dev_err(spi_imx->dev, "No setup_wml()?\n");
1394		ret = -EINVAL;
1395		goto dma_failure_no_start;
1396	}
1397	spi_imx->devtype_data->setup_wml(spi_imx);
1398
1399	/*
1400	 * The TX DMA setup starts the transfer, so make sure RX is configured
1401	 * before TX.
1402	 */
1403	desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
1404				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1405				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1406	if (!desc_rx) {
1407		ret = -EINVAL;
1408		goto dma_failure_no_start;
1409	}
1410
1411	desc_rx->callback = spi_imx_dma_rx_callback;
1412	desc_rx->callback_param = (void *)spi_imx;
1413	dmaengine_submit(desc_rx);
1414	reinit_completion(&spi_imx->dma_rx_completion);
1415	dma_async_issue_pending(controller->dma_rx);
1416
1417	desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
1418				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1419				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1420	if (!desc_tx) {
1421		dmaengine_terminate_all(controller->dma_tx);
1422		dmaengine_terminate_all(controller->dma_rx);
1423		return -EINVAL;
1424	}
1425
1426	desc_tx->callback = spi_imx_dma_tx_callback;
1427	desc_tx->callback_param = (void *)spi_imx;
1428	dmaengine_submit(desc_tx);
1429	reinit_completion(&spi_imx->dma_tx_completion);
1430	dma_async_issue_pending(controller->dma_tx);
1431
1432	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1433
1434	/* Wait SDMA to finish the data transfer.*/
1435	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1436						transfer_timeout);
1437	if (!timeout) {
1438		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1439		dmaengine_terminate_all(controller->dma_tx);
1440		dmaengine_terminate_all(controller->dma_rx);
1441		return -ETIMEDOUT;
1442	}
1443
1444	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1445					      transfer_timeout);
1446	if (!timeout) {
1447		dev_err(&controller->dev, "I/O Error in DMA RX\n");
1448		spi_imx->devtype_data->reset(spi_imx);
1449		dmaengine_terminate_all(controller->dma_rx);
1450		return -ETIMEDOUT;
1451	}
1452
1453	return 0;
1454/* fallback to pio */
1455dma_failure_no_start:
1456	transfer->error |= SPI_TRANS_FAIL_NO_START;
1457	return ret;
1458}
1459
1460static int spi_imx_pio_transfer(struct spi_device *spi,
1461				struct spi_transfer *transfer)
1462{
1463	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1464	unsigned long transfer_timeout;
1465	unsigned long timeout;
1466
1467	spi_imx->tx_buf = transfer->tx_buf;
1468	spi_imx->rx_buf = transfer->rx_buf;
1469	spi_imx->count = transfer->len;
1470	spi_imx->txfifo = 0;
1471	spi_imx->remainder = 0;
1472
1473	reinit_completion(&spi_imx->xfer_done);
1474
1475	spi_imx_push(spi_imx);
1476
1477	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1478
1479	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1480
1481	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1482					      transfer_timeout);
1483	if (!timeout) {
1484		dev_err(&spi->dev, "I/O Error in PIO\n");
1485		spi_imx->devtype_data->reset(spi_imx);
1486		return -ETIMEDOUT;
1487	}
1488
1489	return 0;
1490}
1491
1492static int spi_imx_poll_transfer(struct spi_device *spi,
1493				 struct spi_transfer *transfer)
1494{
1495	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1496	unsigned long timeout;
1497
1498	spi_imx->tx_buf = transfer->tx_buf;
1499	spi_imx->rx_buf = transfer->rx_buf;
1500	spi_imx->count = transfer->len;
1501	spi_imx->txfifo = 0;
1502	spi_imx->remainder = 0;
1503
1504	/* fill in the fifo before timeout calculations if we are
1505	 * interrupted here, then the data is getting transferred by
1506	 * the HW while we are interrupted
1507	 */
1508	spi_imx_push(spi_imx);
1509
1510	timeout = spi_imx_calculate_timeout(spi_imx, transfer->len) + jiffies;
1511	while (spi_imx->txfifo) {
1512		/* RX */
1513		while (spi_imx->txfifo &&
1514		       spi_imx->devtype_data->rx_available(spi_imx)) {
1515			spi_imx->rx(spi_imx);
1516			spi_imx->txfifo--;
1517		}
1518
1519		/* TX */
1520		if (spi_imx->count) {
1521			spi_imx_push(spi_imx);
1522			continue;
1523		}
1524
1525		if (spi_imx->txfifo &&
1526		    time_after(jiffies, timeout)) {
1527
1528			dev_err_ratelimited(&spi->dev,
1529					    "timeout period reached: jiffies: %lu- falling back to interrupt mode\n",
1530					    jiffies - timeout);
1531
1532			/* fall back to interrupt mode */
1533			return spi_imx_pio_transfer(spi, transfer);
1534		}
1535	}
1536
1537	return 0;
1538}
1539
1540static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1541				      struct spi_transfer *transfer)
1542{
1543	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1544	int ret = 0;
1545
1546	if (is_imx53_ecspi(spi_imx) &&
1547	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1548		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1549			MX53_MAX_TRANSFER_BYTES);
1550		return -EMSGSIZE;
1551	}
1552
1553	spi_imx->tx_buf = transfer->tx_buf;
1554	spi_imx->rx_buf = transfer->rx_buf;
1555	spi_imx->count = transfer->len;
1556	spi_imx->txfifo = 0;
1557	spi_imx->remainder = 0;
1558
1559	reinit_completion(&spi_imx->xfer_done);
1560	spi_imx->slave_aborted = false;
1561
1562	spi_imx_push(spi_imx);
1563
1564	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1565
1566	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1567	    spi_imx->slave_aborted) {
1568		dev_dbg(&spi->dev, "interrupted\n");
1569		ret = -EINTR;
1570	}
1571
1572	/* ecspi has a HW issue when works in Slave mode,
1573	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1574	 * ECSPI_TXDATA keeps shift out the last word data,
1575	 * so we have to disable ECSPI when in slave mode after the
1576	 * transfer completes
1577	 */
1578	if (spi_imx->devtype_data->disable)
1579		spi_imx->devtype_data->disable(spi_imx);
1580
1581	return ret;
1582}
1583
1584static int spi_imx_transfer_one(struct spi_controller *controller,
1585				struct spi_device *spi,
1586				struct spi_transfer *transfer)
1587{
1588	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1589	unsigned long hz_per_byte, byte_limit;
1590
1591	spi_imx_setupxfer(spi, transfer);
1592	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1593
1594	/* flush rxfifo before transfer */
1595	while (spi_imx->devtype_data->rx_available(spi_imx))
1596		readl(spi_imx->base + MXC_CSPIRXDATA);
1597
1598	if (spi_imx->slave_mode)
1599		return spi_imx_pio_transfer_slave(spi, transfer);
1600
1601	/*
1602	 * If we decided in spi_imx_can_dma() that we want to do a DMA
1603	 * transfer, the SPI transfer has already been mapped, so we
1604	 * have to do the DMA transfer here.
1605	 */
1606	if (spi_imx->usedma)
1607		return spi_imx_dma_transfer(spi_imx, transfer);
1608	/*
1609	 * Calculate the estimated time in us the transfer runs. Find
1610	 * the number of Hz per byte per polling limit.
1611	 */
1612	hz_per_byte = polling_limit_us ? ((8 + 4) * USEC_PER_SEC) / polling_limit_us : 0;
1613	byte_limit = hz_per_byte ? transfer->effective_speed_hz / hz_per_byte : 1;
1614
1615	/* run in polling mode for short transfers */
1616	if (transfer->len < byte_limit)
1617		return spi_imx_poll_transfer(spi, transfer);
1618
1619	return spi_imx_pio_transfer(spi, transfer);
1620}
1621
1622static int spi_imx_setup(struct spi_device *spi)
1623{
 
 
 
1624	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1625		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1626
 
 
 
 
 
1627	return 0;
1628}
1629
1630static void spi_imx_cleanup(struct spi_device *spi)
1631{
1632}
1633
1634static int
1635spi_imx_prepare_message(struct spi_controller *controller, struct spi_message *msg)
1636{
1637	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1638	int ret;
1639
1640	ret = pm_runtime_resume_and_get(spi_imx->dev);
1641	if (ret < 0) {
1642		dev_err(spi_imx->dev, "failed to enable clock\n");
1643		return ret;
1644	}
1645
1646	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1647	if (ret) {
1648		pm_runtime_mark_last_busy(spi_imx->dev);
1649		pm_runtime_put_autosuspend(spi_imx->dev);
1650	}
1651
1652	return ret;
1653}
1654
1655static int
1656spi_imx_unprepare_message(struct spi_controller *controller, struct spi_message *msg)
1657{
1658	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1659
1660	pm_runtime_mark_last_busy(spi_imx->dev);
1661	pm_runtime_put_autosuspend(spi_imx->dev);
1662	return 0;
1663}
1664
1665static int spi_imx_slave_abort(struct spi_controller *controller)
 
1666{
1667	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1668
1669	spi_imx->slave_aborted = true;
1670	complete(&spi_imx->xfer_done);
1671
 
 
1672	return 0;
1673}
1674
1675static int spi_imx_probe(struct platform_device *pdev)
1676{
1677	struct device_node *np = pdev->dev.of_node;
1678	struct spi_controller *controller;
 
 
 
 
1679	struct spi_imx_data *spi_imx;
1680	struct resource *res;
1681	int ret, irq, spi_drctl;
1682	const struct spi_imx_devtype_data *devtype_data =
1683			of_device_get_match_data(&pdev->dev);
1684	bool slave_mode;
1685	u32 val;
1686
1687	slave_mode = devtype_data->has_slavemode &&
1688			of_property_read_bool(np, "spi-slave");
1689	if (slave_mode)
1690		controller = spi_alloc_slave(&pdev->dev,
1691					     sizeof(struct spi_imx_data));
1692	else
1693		controller = spi_alloc_master(&pdev->dev,
1694					      sizeof(struct spi_imx_data));
1695	if (!controller)
1696		return -ENOMEM;
1697
1698	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1699	if ((ret < 0) || (spi_drctl >= 0x3)) {
1700		/* '11' is reserved */
1701		spi_drctl = 0;
1702	}
1703
1704	platform_set_drvdata(pdev, controller);
 
 
 
 
 
 
1705
1706	controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1707	controller->bus_num = np ? -1 : pdev->id;
1708	controller->use_gpio_descriptors = true;
 
1709
1710	spi_imx = spi_controller_get_devdata(controller);
1711	spi_imx->controller = controller;
 
 
 
 
 
 
1712	spi_imx->dev = &pdev->dev;
1713	spi_imx->slave_mode = slave_mode;
1714
1715	spi_imx->devtype_data = devtype_data;
 
1716
1717	/*
1718	 * Get number of chip selects from device properties. This can be
1719	 * coming from device tree or boardfiles, if it is not defined,
1720	 * a default value of 3 chip selects will be used, as all the legacy
1721	 * board files have <= 3 chip selects.
1722	 */
1723	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1724		controller->num_chipselect = val;
1725	else
1726		controller->num_chipselect = 3;
1727
1728	spi_imx->controller->transfer_one = spi_imx_transfer_one;
1729	spi_imx->controller->setup = spi_imx_setup;
1730	spi_imx->controller->cleanup = spi_imx_cleanup;
1731	spi_imx->controller->prepare_message = spi_imx_prepare_message;
1732	spi_imx->controller->unprepare_message = spi_imx_unprepare_message;
1733	spi_imx->controller->slave_abort = spi_imx_slave_abort;
1734	spi_imx->controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS;
1735
1736	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1737	    is_imx53_ecspi(spi_imx))
1738		spi_imx->controller->mode_bits |= SPI_LOOP | SPI_READY;
1739
1740	if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx))
1741		spi_imx->controller->mode_bits |= SPI_RX_CPHA_FLIP;
1742
1743	if (is_imx51_ecspi(spi_imx) &&
1744	    device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
1745		/*
1746		 * When using HW-CS implementing SPI_CS_WORD can be done by just
1747		 * setting the burst length to the word size. This is
1748		 * considerably faster than manually controlling the CS.
1749		 */
1750		spi_imx->controller->mode_bits |= SPI_CS_WORD;
1751
1752	spi_imx->spi_drctl = spi_drctl;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1753
1754	init_completion(&spi_imx->xfer_done);
1755
1756	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1757	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1758	if (IS_ERR(spi_imx->base)) {
1759		ret = PTR_ERR(spi_imx->base);
1760		goto out_controller_put;
1761	}
1762	spi_imx->base_phys = res->start;
1763
1764	irq = platform_get_irq(pdev, 0);
1765	if (irq < 0) {
1766		ret = irq;
1767		goto out_controller_put;
1768	}
1769
1770	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1771			       dev_name(&pdev->dev), spi_imx);
1772	if (ret) {
1773		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1774		goto out_controller_put;
1775	}
1776
1777	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1778	if (IS_ERR(spi_imx->clk_ipg)) {
1779		ret = PTR_ERR(spi_imx->clk_ipg);
1780		goto out_controller_put;
1781	}
1782
1783	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1784	if (IS_ERR(spi_imx->clk_per)) {
1785		ret = PTR_ERR(spi_imx->clk_per);
1786		goto out_controller_put;
1787	}
1788
1789	ret = clk_prepare_enable(spi_imx->clk_per);
1790	if (ret)
1791		goto out_controller_put;
1792
1793	ret = clk_prepare_enable(spi_imx->clk_ipg);
1794	if (ret)
1795		goto out_put_per;
1796
1797	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1798	pm_runtime_use_autosuspend(spi_imx->dev);
1799	pm_runtime_get_noresume(spi_imx->dev);
1800	pm_runtime_set_active(spi_imx->dev);
1801	pm_runtime_enable(spi_imx->dev);
1802
1803	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1804	/*
1805	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1806	 * if validated on other chips.
1807	 */
1808	if (spi_imx->devtype_data->has_dmamode) {
1809		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, controller);
1810		if (ret == -EPROBE_DEFER)
1811			goto out_runtime_pm_put;
1812
1813		if (ret < 0)
1814			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1815				ret);
1816	}
1817
1818	spi_imx->devtype_data->reset(spi_imx);
1819
1820	spi_imx->devtype_data->intctrl(spi_imx, 0);
1821
1822	controller->dev.of_node = pdev->dev.of_node;
1823	ret = spi_register_controller(controller);
1824	if (ret) {
1825		dev_err_probe(&pdev->dev, ret, "register controller failed\n");
1826		goto out_register_controller;
1827	}
1828
1829	pm_runtime_mark_last_busy(spi_imx->dev);
1830	pm_runtime_put_autosuspend(spi_imx->dev);
1831
 
 
1832	return ret;
1833
1834out_register_controller:
1835	if (spi_imx->devtype_data->has_dmamode)
1836		spi_imx_sdma_exit(spi_imx);
1837out_runtime_pm_put:
1838	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1839	pm_runtime_set_suspended(&pdev->dev);
1840	pm_runtime_disable(spi_imx->dev);
1841
1842	clk_disable_unprepare(spi_imx->clk_ipg);
1843out_put_per:
1844	clk_disable_unprepare(spi_imx->clk_per);
1845out_controller_put:
1846	spi_controller_put(controller);
1847
1848	return ret;
1849}
1850
1851static int spi_imx_remove(struct platform_device *pdev)
1852{
1853	struct spi_controller *controller = platform_get_drvdata(pdev);
1854	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1855	int ret;
1856
1857	spi_unregister_controller(controller);
1858
1859	ret = pm_runtime_resume_and_get(spi_imx->dev);
1860	if (ret < 0) {
1861		dev_err(spi_imx->dev, "failed to enable clock\n");
1862		return ret;
1863	}
1864
1865	writel(0, spi_imx->base + MXC_CSPICTRL);
1866
1867	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1868	pm_runtime_put_sync(spi_imx->dev);
1869	pm_runtime_disable(spi_imx->dev);
1870
1871	spi_imx_sdma_exit(spi_imx);
 
1872
1873	return 0;
1874}
1875
1876static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1877{
1878	struct spi_controller *controller = dev_get_drvdata(dev);
1879	struct spi_imx_data *spi_imx;
1880	int ret;
1881
1882	spi_imx = spi_controller_get_devdata(controller);
1883
1884	ret = clk_prepare_enable(spi_imx->clk_per);
1885	if (ret)
1886		return ret;
1887
1888	ret = clk_prepare_enable(spi_imx->clk_ipg);
1889	if (ret) {
1890		clk_disable_unprepare(spi_imx->clk_per);
1891		return ret;
1892	}
1893
1894	return 0;
1895}
1896
1897static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1898{
1899	struct spi_controller *controller = dev_get_drvdata(dev);
1900	struct spi_imx_data *spi_imx;
1901
1902	spi_imx = spi_controller_get_devdata(controller);
1903
1904	clk_disable_unprepare(spi_imx->clk_per);
1905	clk_disable_unprepare(spi_imx->clk_ipg);
1906
1907	return 0;
1908}
1909
1910static int __maybe_unused spi_imx_suspend(struct device *dev)
1911{
1912	pinctrl_pm_select_sleep_state(dev);
1913	return 0;
1914}
1915
1916static int __maybe_unused spi_imx_resume(struct device *dev)
1917{
1918	pinctrl_pm_select_default_state(dev);
1919	return 0;
1920}
1921
1922static const struct dev_pm_ops imx_spi_pm = {
1923	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1924				spi_imx_runtime_resume, NULL)
1925	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1926};
1927
1928static struct platform_driver spi_imx_driver = {
1929	.driver = {
1930		   .name = DRIVER_NAME,
1931		   .of_match_table = spi_imx_dt_ids,
1932		   .pm = &imx_spi_pm,
1933	},
1934	.probe = spi_imx_probe,
1935	.remove = spi_imx_remove,
1936};
1937module_platform_driver(spi_imx_driver);
1938
1939MODULE_DESCRIPTION("i.MX SPI Controller driver");
1940MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1941MODULE_LICENSE("GPL");
1942MODULE_ALIAS("platform:" DRIVER_NAME);
v4.6
   1/*
   2 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3 * Copyright (C) 2008 Juergen Beisert
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License
   7 * as published by the Free Software Foundation; either version 2
   8 * of the License, or (at your option) any later version.
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write to the
  16 * Free Software Foundation
  17 * 51 Franklin Street, Fifth Floor
  18 * Boston, MA  02110-1301, USA.
  19 */
  20
  21#include <linux/clk.h>
  22#include <linux/completion.h>
  23#include <linux/delay.h>
  24#include <linux/dmaengine.h>
  25#include <linux/dma-mapping.h>
  26#include <linux/err.h>
  27#include <linux/gpio.h>
  28#include <linux/interrupt.h>
  29#include <linux/io.h>
  30#include <linux/irq.h>
  31#include <linux/kernel.h>
  32#include <linux/module.h>
 
  33#include <linux/platform_device.h>
 
  34#include <linux/slab.h>
  35#include <linux/spi/spi.h>
  36#include <linux/spi/spi_bitbang.h>
  37#include <linux/types.h>
  38#include <linux/of.h>
  39#include <linux/of_device.h>
  40#include <linux/of_gpio.h>
  41
  42#include <linux/platform_data/dma-imx.h>
  43#include <linux/platform_data/spi-imx.h>
  44
  45#define DRIVER_NAME "spi_imx"
  46
 
 
 
 
 
 
 
 
 
 
 
 
  47#define MXC_CSPIRXDATA		0x00
  48#define MXC_CSPITXDATA		0x04
  49#define MXC_CSPICTRL		0x08
  50#define MXC_CSPIINT		0x0c
  51#define MXC_RESET		0x1c
  52
  53/* generic defines to abstract from the different register layouts */
  54#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
  55#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
 
  56
  57/* The maximum  bytes that a sdma BD can transfer.*/
  58#define MAX_SDMA_BD_BYTES  (1 << 15)
  59struct spi_imx_config {
  60	unsigned int speed_hz;
  61	unsigned int bpw;
  62	unsigned int mode;
  63	u8 cs;
  64};
  65
  66enum spi_imx_devtype {
  67	IMX1_CSPI,
  68	IMX21_CSPI,
  69	IMX27_CSPI,
  70	IMX31_CSPI,
  71	IMX35_CSPI,	/* CSPI on all i.mx except above */
  72	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
 
  73};
  74
  75struct spi_imx_data;
  76
  77struct spi_imx_devtype_data {
  78	void (*intctrl)(struct spi_imx_data *, int);
  79	int (*config)(struct spi_imx_data *, struct spi_imx_config *);
  80	void (*trigger)(struct spi_imx_data *);
  81	int (*rx_available)(struct spi_imx_data *);
  82	void (*reset)(struct spi_imx_data *);
 
 
 
 
 
 
 
 
 
 
 
 
  83	enum spi_imx_devtype devtype;
  84};
  85
  86struct spi_imx_data {
  87	struct spi_bitbang bitbang;
  88	struct device *dev;
  89
  90	struct completion xfer_done;
  91	void __iomem *base;
  92	unsigned long base_phys;
  93
  94	struct clk *clk_per;
  95	struct clk *clk_ipg;
  96	unsigned long spi_clk;
  97	unsigned int spi_bus_clk;
  98
  99	unsigned int bytes_per_word;
 
 100
 101	unsigned int count;
 102	void (*tx)(struct spi_imx_data *);
 103	void (*rx)(struct spi_imx_data *);
 104	void *rx_buf;
 105	const void *tx_buf;
 106	unsigned int txfifo; /* number of words pushed in tx FIFO */
 
 
 
 
 
 
 
 107
 108	/* DMA */
 109	bool usedma;
 110	u32 wml;
 111	struct completion dma_rx_completion;
 112	struct completion dma_tx_completion;
 113
 114	const struct spi_imx_devtype_data *devtype_data;
 115	int chipselect[0];
 116};
 117
 118static inline int is_imx27_cspi(struct spi_imx_data *d)
 119{
 120	return d->devtype_data->devtype == IMX27_CSPI;
 121}
 122
 123static inline int is_imx35_cspi(struct spi_imx_data *d)
 124{
 125	return d->devtype_data->devtype == IMX35_CSPI;
 126}
 127
 128static inline int is_imx51_ecspi(struct spi_imx_data *d)
 129{
 130	return d->devtype_data->devtype == IMX51_ECSPI;
 131}
 132
 133static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
 134{
 135	return is_imx51_ecspi(d) ? 64 : 8;
 136}
 137
 138#define MXC_SPI_BUF_RX(type)						\
 139static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 140{									\
 141	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 142									\
 143	if (spi_imx->rx_buf) {						\
 144		*(type *)spi_imx->rx_buf = val;				\
 145		spi_imx->rx_buf += sizeof(type);			\
 146	}								\
 
 
 147}
 148
 149#define MXC_SPI_BUF_TX(type)						\
 150static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 151{									\
 152	type val = 0;							\
 153									\
 154	if (spi_imx->tx_buf) {						\
 155		val = *(type *)spi_imx->tx_buf;				\
 156		spi_imx->tx_buf += sizeof(type);			\
 157	}								\
 158									\
 159	spi_imx->count -= sizeof(type);					\
 160									\
 161	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 162}
 163
 164MXC_SPI_BUF_RX(u8)
 165MXC_SPI_BUF_TX(u8)
 166MXC_SPI_BUF_RX(u16)
 167MXC_SPI_BUF_TX(u16)
 168MXC_SPI_BUF_RX(u32)
 169MXC_SPI_BUF_TX(u32)
 170
 171/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 172 * (which is currently not the case in this driver)
 173 */
 174static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 175	256, 384, 512, 768, 1024};
 176
 177/* MX21, MX27 */
 178static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 179		unsigned int fspi, unsigned int max)
 180{
 181	int i;
 182
 183	for (i = 2; i < max; i++)
 184		if (fspi * mxc_clkdivs[i] >= fin)
 185			return i;
 186
 187	return max;
 
 188}
 189
 190/* MX1, MX31, MX35, MX51 CSPI */
 191static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 192		unsigned int fspi)
 193{
 194	int i, div = 4;
 195
 196	for (i = 0; i < 7; i++) {
 197		if (fspi * div >= fin)
 198			return i;
 199		div <<= 1;
 200	}
 201
 202	return 7;
 
 
 203}
 204
 205static int spi_imx_bytes_per_word(const int bpw)
 206{
 207	return DIV_ROUND_UP(bpw, BITS_PER_BYTE);
 
 
 
 
 
 208}
 209
 210static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 211			 struct spi_transfer *transfer)
 212{
 213	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 214	unsigned int bpw;
 215
 216	if (!master->dma_rx)
 217		return false;
 218
 219	if (!transfer)
 220		return false;
 221
 222	bpw = transfer->bits_per_word;
 223	if (!bpw)
 224		bpw = spi->bits_per_word;
 225
 226	bpw = spi_imx_bytes_per_word(bpw);
 227
 228	if (bpw != 1 && bpw != 2 && bpw != 4)
 229		return false;
 230
 231	if (transfer->len < spi_imx->wml * bpw)
 232		return false;
 233
 234	if (transfer->len % (spi_imx->wml * bpw))
 235		return false;
 236
 237	return true;
 238}
 239
 240#define MX51_ECSPI_CTRL		0x08
 241#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
 242#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 243#define MX51_ECSPI_CTRL_SMC		(1 << 3)
 244#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 
 245#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
 246#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 247#define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
 248#define MX51_ECSPI_CTRL_BL_OFFSET	20
 
 249
 250#define MX51_ECSPI_CONFIG	0x0c
 251#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
 252#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
 253#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
 254#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
 255#define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
 256
 257#define MX51_ECSPI_INT		0x10
 258#define MX51_ECSPI_INT_TEEN		(1 <<  0)
 259#define MX51_ECSPI_INT_RREN		(1 <<  3)
 
 260
 261#define MX51_ECSPI_DMA      0x14
 262#define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
 263#define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
 264#define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
 265
 266#define MX51_ECSPI_DMA_TEDEN		(1 << 7)
 267#define MX51_ECSPI_DMA_RXDEN		(1 << 23)
 268#define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
 269
 270#define MX51_ECSPI_STAT		0x18
 271#define MX51_ECSPI_STAT_RR		(1 <<  3)
 272
 273#define MX51_ECSPI_TESTREG	0x20
 274#define MX51_ECSPI_TESTREG_LBC	BIT(31)
 275
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 276/* MX51 eCSPI */
 277static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 278				      unsigned int fspi, unsigned int *fres)
 279{
 280	/*
 281	 * there are two 4-bit dividers, the pre-divider divides by
 282	 * $pre, the post-divider by 2^$post
 283	 */
 284	unsigned int pre, post;
 285	unsigned int fin = spi_imx->spi_clk;
 286
 287	if (unlikely(fspi > fin))
 288		return 0;
 289
 290	post = fls(fin) - fls(fspi);
 291	if (fin > fspi << post)
 292		post++;
 293
 294	/* now we have: (fin <= fspi << post) with post being minimal */
 295
 296	post = max(4U, post) - 4;
 297	if (unlikely(post > 0xf)) {
 298		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 299				fspi, fin);
 300		return 0xff;
 301	}
 302
 303	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 304
 305	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 306			__func__, fin, fspi, post, pre);
 307
 308	/* Resulting frequency for the SCLK line. */
 309	*fres = (fin / (pre + 1)) >> post;
 310
 311	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 312		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 313}
 314
 315static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 316{
 317	unsigned val = 0;
 318
 319	if (enable & MXC_INT_TE)
 320		val |= MX51_ECSPI_INT_TEEN;
 321
 322	if (enable & MXC_INT_RR)
 323		val |= MX51_ECSPI_INT_RREN;
 324
 
 
 
 325	writel(val, spi_imx->base + MX51_ECSPI_INT);
 326}
 327
 328static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 329{
 330	u32 reg;
 331
 332	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 333	reg |= MX51_ECSPI_CTRL_XCH;
 334	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 335}
 336
 337static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
 338		struct spi_imx_config *config)
 339{
 
 
 
 
 
 
 
 
 
 
 
 
 340	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 341	u32 clk = config->speed_hz, delay, reg;
 
 342	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 
 
 
 
 
 
 
 343
 344	/*
 345	 * The hardware seems to have a race condition when changing modes. The
 346	 * current assumption is that the selection of the channel arrives
 347	 * earlier in the hardware than the mode bits when they are written at
 348	 * the same time.
 349	 * So set master mode for all channels as we do not support slave mode.
 350	 */
 351	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 352
 353	/* set clock speed */
 354	ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk);
 355	spi_imx->spi_bus_clk = clk;
 356
 357	/* set chip select to use */
 358	ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
 359
 360	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
 
 
 
 
 361
 362	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
 
 
 
 
 
 363
 364	if (config->mode & SPI_CPHA)
 365		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
 
 
 
 
 
 366	else
 367		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
 368
 369	if (config->mode & SPI_CPOL) {
 370		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
 371		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
 372	} else {
 373		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
 374		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
 375	}
 376	if (config->mode & SPI_CS_HIGH)
 377		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
 
 378	else
 379		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(config->cs);
 380
 381	if (spi_imx->usedma)
 382		ctrl |= MX51_ECSPI_CTRL_SMC;
 383
 384	/* CTRL register always go first to bring out controller from reset */
 385	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 386
 387	reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 388	if (config->mode & SPI_LOOP)
 389		reg |= MX51_ECSPI_TESTREG_LBC;
 390	else
 391		reg &= ~MX51_ECSPI_TESTREG_LBC;
 392	writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
 393
 394	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 395
 396	/*
 397	 * Wait until the changes in the configuration register CONFIGREG
 398	 * propagate into the hardware. It takes exactly one tick of the
 399	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 400	 * effect of the delay it takes for the hardware to apply changes
 401	 * is noticable if the SCLK clock run very slow. In such a case, if
 402	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 403	 * be asserted before the SCLK polarity changes, which would disrupt
 404	 * the SPI communication as the device on the other end would consider
 405	 * the change of SCLK polarity as a clock tick already.
 
 
 
 
 
 
 406	 */
 407	delay = (2 * 1000000) / clk;
 408	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
 
 
 
 
 
 
 409		udelay(delay);
 410	else			/* SCLK is _very_ slow */
 411		usleep_range(delay, delay + 10);
 412
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 413	/*
 414	 * Configure the DMA register: setup the watermark
 415	 * and enable DMA request.
 416	 */
 417
 418	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
 419		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 420		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 421		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 422		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 423
 424	return 0;
 425}
 426
 427static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 428{
 429	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 430}
 431
 432static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 433{
 434	/* drain receive buffer */
 435	while (mx51_ecspi_rx_available(spi_imx))
 436		readl(spi_imx->base + MXC_CSPIRXDATA);
 437}
 438
 439#define MX31_INTREG_TEEN	(1 << 0)
 440#define MX31_INTREG_RREN	(1 << 3)
 441
 442#define MX31_CSPICTRL_ENABLE	(1 << 0)
 443#define MX31_CSPICTRL_MASTER	(1 << 1)
 444#define MX31_CSPICTRL_XCH	(1 << 2)
 
 445#define MX31_CSPICTRL_POL	(1 << 4)
 446#define MX31_CSPICTRL_PHA	(1 << 5)
 447#define MX31_CSPICTRL_SSCTL	(1 << 6)
 448#define MX31_CSPICTRL_SSPOL	(1 << 7)
 449#define MX31_CSPICTRL_BC_SHIFT	8
 450#define MX35_CSPICTRL_BL_SHIFT	20
 451#define MX31_CSPICTRL_CS_SHIFT	24
 452#define MX35_CSPICTRL_CS_SHIFT	12
 453#define MX31_CSPICTRL_DR_SHIFT	16
 454
 
 
 
 
 455#define MX31_CSPISTATUS		0x14
 456#define MX31_STATUS_RR		(1 << 3)
 457
 
 
 
 458/* These functions also work for the i.MX35, but be aware that
 459 * the i.MX35 has a slightly different register layout for bits
 460 * we do not use here.
 461 */
 462static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 463{
 464	unsigned int val = 0;
 465
 466	if (enable & MXC_INT_TE)
 467		val |= MX31_INTREG_TEEN;
 468	if (enable & MXC_INT_RR)
 469		val |= MX31_INTREG_RREN;
 470
 471	writel(val, spi_imx->base + MXC_CSPIINT);
 472}
 473
 474static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
 475{
 476	unsigned int reg;
 477
 478	reg = readl(spi_imx->base + MXC_CSPICTRL);
 479	reg |= MX31_CSPICTRL_XCH;
 480	writel(reg, spi_imx->base + MXC_CSPICTRL);
 481}
 482
 483static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
 484		struct spi_imx_config *config)
 
 
 
 
 
 
 485{
 486	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 487	int cs = spi_imx->chipselect[config->cs];
 488
 489	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 490		MX31_CSPICTRL_DR_SHIFT;
 
 491
 492	if (is_imx35_cspi(spi_imx)) {
 493		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
 494		reg |= MX31_CSPICTRL_SSCTL;
 495	} else {
 496		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
 497	}
 498
 499	if (config->mode & SPI_CPHA)
 500		reg |= MX31_CSPICTRL_PHA;
 501	if (config->mode & SPI_CPOL)
 502		reg |= MX31_CSPICTRL_POL;
 503	if (config->mode & SPI_CS_HIGH)
 504		reg |= MX31_CSPICTRL_SSPOL;
 505	if (cs < 0)
 506		reg |= (cs + 32) <<
 507			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 508						  MX31_CSPICTRL_CS_SHIFT);
 509
 
 
 
 510	writel(reg, spi_imx->base + MXC_CSPICTRL);
 511
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 512	return 0;
 513}
 514
 515static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
 516{
 517	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 518}
 519
 520static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
 521{
 522	/* drain receive buffer */
 523	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 524		readl(spi_imx->base + MXC_CSPIRXDATA);
 525}
 526
 527#define MX21_INTREG_RR		(1 << 4)
 528#define MX21_INTREG_TEEN	(1 << 9)
 529#define MX21_INTREG_RREN	(1 << 13)
 530
 531#define MX21_CSPICTRL_POL	(1 << 5)
 532#define MX21_CSPICTRL_PHA	(1 << 6)
 533#define MX21_CSPICTRL_SSPOL	(1 << 8)
 534#define MX21_CSPICTRL_XCH	(1 << 9)
 535#define MX21_CSPICTRL_ENABLE	(1 << 10)
 536#define MX21_CSPICTRL_MASTER	(1 << 11)
 537#define MX21_CSPICTRL_DR_SHIFT	14
 538#define MX21_CSPICTRL_CS_SHIFT	19
 539
 540static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 541{
 542	unsigned int val = 0;
 543
 544	if (enable & MXC_INT_TE)
 545		val |= MX21_INTREG_TEEN;
 546	if (enable & MXC_INT_RR)
 547		val |= MX21_INTREG_RREN;
 548
 549	writel(val, spi_imx->base + MXC_CSPIINT);
 550}
 551
 552static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
 553{
 554	unsigned int reg;
 555
 556	reg = readl(spi_imx->base + MXC_CSPICTRL);
 557	reg |= MX21_CSPICTRL_XCH;
 558	writel(reg, spi_imx->base + MXC_CSPICTRL);
 559}
 560
 561static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
 562		struct spi_imx_config *config)
 
 
 
 
 
 
 563{
 564	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 565	int cs = spi_imx->chipselect[config->cs];
 566	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 
 567
 568	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
 569		MX21_CSPICTRL_DR_SHIFT;
 570	reg |= config->bpw - 1;
 571
 572	if (config->mode & SPI_CPHA)
 
 
 573		reg |= MX21_CSPICTRL_PHA;
 574	if (config->mode & SPI_CPOL)
 575		reg |= MX21_CSPICTRL_POL;
 576	if (config->mode & SPI_CS_HIGH)
 577		reg |= MX21_CSPICTRL_SSPOL;
 578	if (cs < 0)
 579		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
 580
 581	writel(reg, spi_imx->base + MXC_CSPICTRL);
 582
 583	return 0;
 584}
 585
 586static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
 587{
 588	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 589}
 590
 591static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
 592{
 593	writel(1, spi_imx->base + MXC_RESET);
 594}
 595
 596#define MX1_INTREG_RR		(1 << 3)
 597#define MX1_INTREG_TEEN		(1 << 8)
 598#define MX1_INTREG_RREN		(1 << 11)
 599
 600#define MX1_CSPICTRL_POL	(1 << 4)
 601#define MX1_CSPICTRL_PHA	(1 << 5)
 602#define MX1_CSPICTRL_XCH	(1 << 8)
 603#define MX1_CSPICTRL_ENABLE	(1 << 9)
 604#define MX1_CSPICTRL_MASTER	(1 << 10)
 605#define MX1_CSPICTRL_DR_SHIFT	13
 606
 607static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 608{
 609	unsigned int val = 0;
 610
 611	if (enable & MXC_INT_TE)
 612		val |= MX1_INTREG_TEEN;
 613	if (enable & MXC_INT_RR)
 614		val |= MX1_INTREG_RREN;
 615
 616	writel(val, spi_imx->base + MXC_CSPIINT);
 617}
 618
 619static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
 620{
 621	unsigned int reg;
 622
 623	reg = readl(spi_imx->base + MXC_CSPICTRL);
 624	reg |= MX1_CSPICTRL_XCH;
 625	writel(reg, spi_imx->base + MXC_CSPICTRL);
 626}
 627
 628static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
 629		struct spi_imx_config *config)
 
 
 
 
 
 
 630{
 631	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 
 632
 633	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 634		MX1_CSPICTRL_DR_SHIFT;
 635	reg |= config->bpw - 1;
 
 
 636
 637	if (config->mode & SPI_CPHA)
 638		reg |= MX1_CSPICTRL_PHA;
 639	if (config->mode & SPI_CPOL)
 640		reg |= MX1_CSPICTRL_POL;
 641
 642	writel(reg, spi_imx->base + MXC_CSPICTRL);
 643
 644	return 0;
 645}
 646
 647static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
 648{
 649	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 650}
 651
 652static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
 653{
 654	writel(1, spi_imx->base + MXC_RESET);
 655}
 656
 657static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 658	.intctrl = mx1_intctrl,
 659	.config = mx1_config,
 
 660	.trigger = mx1_trigger,
 661	.rx_available = mx1_rx_available,
 662	.reset = mx1_reset,
 
 
 
 
 663	.devtype = IMX1_CSPI,
 664};
 665
 666static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 667	.intctrl = mx21_intctrl,
 668	.config = mx21_config,
 
 669	.trigger = mx21_trigger,
 670	.rx_available = mx21_rx_available,
 671	.reset = mx21_reset,
 
 
 
 
 672	.devtype = IMX21_CSPI,
 673};
 674
 675static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 676	/* i.mx27 cspi shares the functions with i.mx21 one */
 677	.intctrl = mx21_intctrl,
 678	.config = mx21_config,
 
 679	.trigger = mx21_trigger,
 680	.rx_available = mx21_rx_available,
 681	.reset = mx21_reset,
 
 
 
 
 682	.devtype = IMX27_CSPI,
 683};
 684
 685static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 686	.intctrl = mx31_intctrl,
 687	.config = mx31_config,
 
 688	.trigger = mx31_trigger,
 689	.rx_available = mx31_rx_available,
 690	.reset = mx31_reset,
 
 
 
 
 691	.devtype = IMX31_CSPI,
 692};
 693
 694static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 695	/* i.mx35 and later cspi shares the functions with i.mx31 one */
 696	.intctrl = mx31_intctrl,
 697	.config = mx31_config,
 
 698	.trigger = mx31_trigger,
 699	.rx_available = mx31_rx_available,
 700	.reset = mx31_reset,
 
 
 
 
 701	.devtype = IMX35_CSPI,
 702};
 703
 704static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 705	.intctrl = mx51_ecspi_intctrl,
 706	.config = mx51_ecspi_config,
 
 707	.trigger = mx51_ecspi_trigger,
 708	.rx_available = mx51_ecspi_rx_available,
 709	.reset = mx51_ecspi_reset,
 
 
 
 
 
 
 710	.devtype = IMX51_ECSPI,
 711};
 712
 713static const struct platform_device_id spi_imx_devtype[] = {
 714	{
 715		.name = "imx1-cspi",
 716		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
 717	}, {
 718		.name = "imx21-cspi",
 719		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
 720	}, {
 721		.name = "imx27-cspi",
 722		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
 723	}, {
 724		.name = "imx31-cspi",
 725		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
 726	}, {
 727		.name = "imx35-cspi",
 728		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
 729	}, {
 730		.name = "imx51-ecspi",
 731		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
 732	}, {
 733		/* sentinel */
 734	}
 
 
 
 
 
 
 
 735};
 736
 737static const struct of_device_id spi_imx_dt_ids[] = {
 738	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
 739	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
 740	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
 741	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
 742	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
 743	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
 
 
 744	{ /* sentinel */ }
 745};
 746MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
 747
 748static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 749{
 750	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 751	int gpio = spi_imx->chipselect[spi->chip_select];
 752	int active = is_active != BITBANG_CS_INACTIVE;
 753	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
 754
 755	if (!gpio_is_valid(gpio))
 756		return;
 757
 758	gpio_set_value(gpio, dev_is_lowactive ^ active);
 759}
 760
 761static void spi_imx_push(struct spi_imx_data *spi_imx)
 762{
 763	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 764		if (!spi_imx->count)
 765			break;
 
 
 
 766		spi_imx->tx(spi_imx);
 767		spi_imx->txfifo++;
 768	}
 769
 770	spi_imx->devtype_data->trigger(spi_imx);
 
 771}
 772
 773static irqreturn_t spi_imx_isr(int irq, void *dev_id)
 774{
 775	struct spi_imx_data *spi_imx = dev_id;
 776
 777	while (spi_imx->devtype_data->rx_available(spi_imx)) {
 
 778		spi_imx->rx(spi_imx);
 779		spi_imx->txfifo--;
 780	}
 781
 782	if (spi_imx->count) {
 783		spi_imx_push(spi_imx);
 784		return IRQ_HANDLED;
 785	}
 786
 787	if (spi_imx->txfifo) {
 788		/* No data left to push, but still waiting for rx data,
 789		 * enable receive data available interrupt.
 790		 */
 791		spi_imx->devtype_data->intctrl(
 792				spi_imx, MXC_INT_RR);
 793		return IRQ_HANDLED;
 794	}
 795
 796	spi_imx->devtype_data->intctrl(spi_imx, 0);
 797	complete(&spi_imx->xfer_done);
 798
 799	return IRQ_HANDLED;
 800}
 801
 802static int spi_imx_dma_configure(struct spi_master *master,
 803				 int bytes_per_word)
 804{
 805	int ret;
 806	enum dma_slave_buswidth buswidth;
 807	struct dma_slave_config rx = {}, tx = {};
 808	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 809
 810	if (bytes_per_word == spi_imx->bytes_per_word)
 811		/* Same as last time */
 812		return 0;
 813
 814	switch (bytes_per_word) {
 815	case 4:
 816		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 817		break;
 818	case 2:
 819		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
 820		break;
 821	case 1:
 822		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
 823		break;
 824	default:
 825		return -EINVAL;
 826	}
 827
 828	tx.direction = DMA_MEM_TO_DEV;
 829	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
 830	tx.dst_addr_width = buswidth;
 831	tx.dst_maxburst = spi_imx->wml;
 832	ret = dmaengine_slave_config(master->dma_tx, &tx);
 833	if (ret) {
 834		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
 835		return ret;
 836	}
 837
 838	rx.direction = DMA_DEV_TO_MEM;
 839	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
 840	rx.src_addr_width = buswidth;
 841	rx.src_maxburst = spi_imx->wml;
 842	ret = dmaengine_slave_config(master->dma_rx, &rx);
 843	if (ret) {
 844		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
 845		return ret;
 846	}
 847
 848	spi_imx->bytes_per_word = bytes_per_word;
 849
 850	return 0;
 851}
 852
 853static int spi_imx_setupxfer(struct spi_device *spi,
 854				 struct spi_transfer *t)
 855{
 856	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 857	struct spi_imx_config config;
 858	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 859
 860	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
 861	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
 862	config.mode = spi->mode;
 863	config.cs = spi->chip_select;
 864
 865	if (!config.speed_hz)
 866		config.speed_hz = spi->max_speed_hz;
 867	if (!config.bpw)
 868		config.bpw = spi->bits_per_word;
 869
 870	/* Initialize the functions for transfer */
 871	if (config.bpw <= 8) {
 872		spi_imx->rx = spi_imx_buf_rx_u8;
 873		spi_imx->tx = spi_imx_buf_tx_u8;
 874	} else if (config.bpw <= 16) {
 875		spi_imx->rx = spi_imx_buf_rx_u16;
 876		spi_imx->tx = spi_imx_buf_tx_u16;
 877	} else {
 878		spi_imx->rx = spi_imx_buf_rx_u32;
 879		spi_imx->tx = spi_imx_buf_tx_u32;
 
 
 
 
 
 
 
 
 
 880	}
 881
 882	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
 883		spi_imx->usedma = 1;
 884	else
 885		spi_imx->usedma = 0;
 886
 887	if (spi_imx->usedma) {
 888		ret = spi_imx_dma_configure(spi->master,
 889					    spi_imx_bytes_per_word(config.bpw));
 890		if (ret)
 891			return ret;
 
 
 892	}
 893
 894	spi_imx->devtype_data->config(spi_imx, &config);
 895
 896	return 0;
 897}
 898
 899static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
 900{
 901	struct spi_master *master = spi_imx->bitbang.master;
 902
 903	if (master->dma_rx) {
 904		dma_release_channel(master->dma_rx);
 905		master->dma_rx = NULL;
 906	}
 907
 908	if (master->dma_tx) {
 909		dma_release_channel(master->dma_tx);
 910		master->dma_tx = NULL;
 911	}
 912}
 913
 914static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
 915			     struct spi_master *master)
 916{
 917	int ret;
 918
 919	/* use pio mode for i.mx6dl chip TKT238285 */
 920	if (of_machine_is_compatible("fsl,imx6dl"))
 921		return 0;
 922
 923	spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2;
 924
 925	/* Prepare for TX DMA: */
 926	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
 927	if (IS_ERR(master->dma_tx)) {
 928		ret = PTR_ERR(master->dma_tx);
 929		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
 930		master->dma_tx = NULL;
 931		goto err;
 932	}
 933
 934	/* Prepare for RX : */
 935	master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
 936	if (IS_ERR(master->dma_rx)) {
 937		ret = PTR_ERR(master->dma_rx);
 938		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
 939		master->dma_rx = NULL;
 940		goto err;
 941	}
 942
 943	spi_imx_dma_configure(master, 1);
 944
 945	init_completion(&spi_imx->dma_rx_completion);
 946	init_completion(&spi_imx->dma_tx_completion);
 947	master->can_dma = spi_imx_can_dma;
 948	master->max_dma_len = MAX_SDMA_BD_BYTES;
 949	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
 950					 SPI_MASTER_MUST_TX;
 951
 952	return 0;
 953err:
 954	spi_imx_sdma_exit(spi_imx);
 955	return ret;
 956}
 957
 958static void spi_imx_dma_rx_callback(void *cookie)
 959{
 960	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 961
 962	complete(&spi_imx->dma_rx_completion);
 963}
 964
 965static void spi_imx_dma_tx_callback(void *cookie)
 966{
 967	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
 968
 969	complete(&spi_imx->dma_tx_completion);
 970}
 971
 972static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
 973{
 974	unsigned long timeout = 0;
 975
 976	/* Time with actual data transfer and CS change delay related to HW */
 977	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
 978
 979	/* Add extra second for scheduler related activities */
 980	timeout += 1;
 981
 982	/* Double calculated timeout */
 983	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
 984}
 985
 986static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
 987				struct spi_transfer *transfer)
 988{
 989	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
 990	unsigned long transfer_timeout;
 991	unsigned long timeout;
 992	struct spi_master *master = spi_imx->bitbang.master;
 993	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 994
 995	/*
 996	 * The TX DMA setup starts the transfer, so make sure RX is configured
 997	 * before TX.
 998	 */
 999	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1000				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1001				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1002	if (!desc_rx)
1003		return -EINVAL;
 
 
1004
1005	desc_rx->callback = spi_imx_dma_rx_callback;
1006	desc_rx->callback_param = (void *)spi_imx;
1007	dmaengine_submit(desc_rx);
1008	reinit_completion(&spi_imx->dma_rx_completion);
1009	dma_async_issue_pending(master->dma_rx);
1010
1011	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1012				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1013				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1014	if (!desc_tx) {
1015		dmaengine_terminate_all(master->dma_tx);
 
1016		return -EINVAL;
1017	}
1018
1019	desc_tx->callback = spi_imx_dma_tx_callback;
1020	desc_tx->callback_param = (void *)spi_imx;
1021	dmaengine_submit(desc_tx);
1022	reinit_completion(&spi_imx->dma_tx_completion);
1023	dma_async_issue_pending(master->dma_tx);
1024
1025	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1026
1027	/* Wait SDMA to finish the data transfer.*/
1028	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1029						transfer_timeout);
1030	if (!timeout) {
1031		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1032		dmaengine_terminate_all(master->dma_tx);
1033		dmaengine_terminate_all(master->dma_rx);
1034		return -ETIMEDOUT;
1035	}
1036
1037	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1038					      transfer_timeout);
1039	if (!timeout) {
1040		dev_err(&master->dev, "I/O Error in DMA RX\n");
1041		spi_imx->devtype_data->reset(spi_imx);
1042		dmaengine_terminate_all(master->dma_rx);
1043		return -ETIMEDOUT;
1044	}
1045
1046	return transfer->len;
 
 
 
 
1047}
1048
1049static int spi_imx_pio_transfer(struct spi_device *spi,
1050				struct spi_transfer *transfer)
1051{
1052	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
 
1053
1054	spi_imx->tx_buf = transfer->tx_buf;
1055	spi_imx->rx_buf = transfer->rx_buf;
1056	spi_imx->count = transfer->len;
1057	spi_imx->txfifo = 0;
 
1058
1059	reinit_completion(&spi_imx->xfer_done);
1060
1061	spi_imx_push(spi_imx);
1062
1063	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1064
1065	wait_for_completion(&spi_imx->xfer_done);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1066
1067	return transfer->len;
 
 
 
 
 
1068}
1069
1070static int spi_imx_transfer(struct spi_device *spi,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1071				struct spi_transfer *transfer)
1072{
1073	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
 
 
 
 
 
 
 
 
 
 
1074
 
 
 
 
 
1075	if (spi_imx->usedma)
1076		return spi_imx_dma_transfer(spi_imx, transfer);
1077	else
1078		return spi_imx_pio_transfer(spi, transfer);
 
 
 
 
 
 
 
 
 
 
1079}
1080
1081static int spi_imx_setup(struct spi_device *spi)
1082{
1083	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1084	int gpio = spi_imx->chipselect[spi->chip_select];
1085
1086	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1087		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1088
1089	if (gpio_is_valid(gpio))
1090		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
1091
1092	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1093
1094	return 0;
1095}
1096
1097static void spi_imx_cleanup(struct spi_device *spi)
1098{
1099}
1100
1101static int
1102spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1103{
1104	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1105	int ret;
1106
1107	ret = clk_enable(spi_imx->clk_per);
1108	if (ret)
 
1109		return ret;
 
1110
1111	ret = clk_enable(spi_imx->clk_ipg);
1112	if (ret) {
1113		clk_disable(spi_imx->clk_per);
1114		return ret;
1115	}
1116
 
 
 
 
 
 
 
 
 
 
1117	return 0;
1118}
1119
1120static int
1121spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1122{
1123	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 
 
 
1124
1125	clk_disable(spi_imx->clk_ipg);
1126	clk_disable(spi_imx->clk_per);
1127	return 0;
1128}
1129
1130static int spi_imx_probe(struct platform_device *pdev)
1131{
1132	struct device_node *np = pdev->dev.of_node;
1133	const struct of_device_id *of_id =
1134			of_match_device(spi_imx_dt_ids, &pdev->dev);
1135	struct spi_imx_master *mxc_platform_info =
1136			dev_get_platdata(&pdev->dev);
1137	struct spi_master *master;
1138	struct spi_imx_data *spi_imx;
1139	struct resource *res;
1140	int i, ret, num_cs, irq;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1141
1142	if (!np && !mxc_platform_info) {
1143		dev_err(&pdev->dev, "can't get the platform data\n");
1144		return -EINVAL;
 
1145	}
1146
1147	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
1148	if (ret < 0) {
1149		if (mxc_platform_info)
1150			num_cs = mxc_platform_info->num_chipselect;
1151		else
1152			return ret;
1153	}
1154
1155	master = spi_alloc_master(&pdev->dev,
1156			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
1157	if (!master)
1158		return -ENOMEM;
1159
1160	platform_set_drvdata(pdev, master);
1161
1162	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1163	master->bus_num = pdev->id;
1164	master->num_chipselect = num_cs;
1165
1166	spi_imx = spi_master_get_devdata(master);
1167	spi_imx->bitbang.master = master;
1168	spi_imx->dev = &pdev->dev;
 
1169
1170	spi_imx->devtype_data = of_id ? of_id->data :
1171		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1172
1173	for (i = 0; i < master->num_chipselect; i++) {
1174		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
1175		if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
1176			cs_gpio = mxc_platform_info->chipselect[i];
 
 
 
 
 
 
1177
1178		spi_imx->chipselect[i] = cs_gpio;
1179		if (!gpio_is_valid(cs_gpio))
1180			continue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1181
1182		ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
1183					DRIVER_NAME);
1184		if (ret) {
1185			dev_err(&pdev->dev, "can't get cs gpios\n");
1186			goto out_master_put;
1187		}
1188	}
1189
1190	spi_imx->bitbang.chipselect = spi_imx_chipselect;
1191	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1192	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1193	spi_imx->bitbang.master->setup = spi_imx_setup;
1194	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1195	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1196	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1197	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1198	if (is_imx51_ecspi(spi_imx))
1199		spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
1200
1201	init_completion(&spi_imx->xfer_done);
1202
1203	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1204	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1205	if (IS_ERR(spi_imx->base)) {
1206		ret = PTR_ERR(spi_imx->base);
1207		goto out_master_put;
1208	}
1209	spi_imx->base_phys = res->start;
1210
1211	irq = platform_get_irq(pdev, 0);
1212	if (irq < 0) {
1213		ret = irq;
1214		goto out_master_put;
1215	}
1216
1217	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1218			       dev_name(&pdev->dev), spi_imx);
1219	if (ret) {
1220		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1221		goto out_master_put;
1222	}
1223
1224	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1225	if (IS_ERR(spi_imx->clk_ipg)) {
1226		ret = PTR_ERR(spi_imx->clk_ipg);
1227		goto out_master_put;
1228	}
1229
1230	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1231	if (IS_ERR(spi_imx->clk_per)) {
1232		ret = PTR_ERR(spi_imx->clk_per);
1233		goto out_master_put;
1234	}
1235
1236	ret = clk_prepare_enable(spi_imx->clk_per);
1237	if (ret)
1238		goto out_master_put;
1239
1240	ret = clk_prepare_enable(spi_imx->clk_ipg);
1241	if (ret)
1242		goto out_put_per;
1243
 
 
 
 
 
 
1244	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1245	/*
1246	 * Only validated on i.mx6 now, can remove the constrain if validated on
1247	 * other chips.
1248	 */
1249	if (is_imx51_ecspi(spi_imx)) {
1250		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1251		if (ret == -EPROBE_DEFER)
1252			goto out_clk_put;
1253
1254		if (ret < 0)
1255			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1256				ret);
1257	}
1258
1259	spi_imx->devtype_data->reset(spi_imx);
1260
1261	spi_imx->devtype_data->intctrl(spi_imx, 0);
1262
1263	master->dev.of_node = pdev->dev.of_node;
1264	ret = spi_bitbang_start(&spi_imx->bitbang);
1265	if (ret) {
1266		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1267		goto out_clk_put;
1268	}
1269
1270	dev_info(&pdev->dev, "probed\n");
 
1271
1272	clk_disable(spi_imx->clk_ipg);
1273	clk_disable(spi_imx->clk_per);
1274	return ret;
1275
1276out_clk_put:
 
 
 
 
 
 
 
1277	clk_disable_unprepare(spi_imx->clk_ipg);
1278out_put_per:
1279	clk_disable_unprepare(spi_imx->clk_per);
1280out_master_put:
1281	spi_master_put(master);
1282
1283	return ret;
1284}
1285
1286static int spi_imx_remove(struct platform_device *pdev)
1287{
1288	struct spi_master *master = platform_get_drvdata(pdev);
1289	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 
 
 
1290
1291	spi_bitbang_stop(&spi_imx->bitbang);
 
 
 
 
1292
1293	writel(0, spi_imx->base + MXC_CSPICTRL);
1294	clk_unprepare(spi_imx->clk_ipg);
1295	clk_unprepare(spi_imx->clk_per);
 
 
 
1296	spi_imx_sdma_exit(spi_imx);
1297	spi_master_put(master);
1298
1299	return 0;
1300}
1301
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1302static struct platform_driver spi_imx_driver = {
1303	.driver = {
1304		   .name = DRIVER_NAME,
1305		   .of_match_table = spi_imx_dt_ids,
1306		   },
1307	.id_table = spi_imx_devtype,
1308	.probe = spi_imx_probe,
1309	.remove = spi_imx_remove,
1310};
1311module_platform_driver(spi_imx_driver);
1312
1313MODULE_DESCRIPTION("SPI Master Controller driver");
1314MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1315MODULE_LICENSE("GPL");
1316MODULE_ALIAS("platform:" DRIVER_NAME);