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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);
v6.13.7
   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/bits.h>
   6#include <linux/bitfield.h>
   7#include <linux/clk.h>
   8#include <linux/completion.h>
   9#include <linux/delay.h>
  10#include <linux/dmaengine.h>
  11#include <linux/dma-mapping.h>
  12#include <linux/err.h>
  13#include <linux/interrupt.h>
  14#include <linux/io.h>
  15#include <linux/irq.h>
  16#include <linux/kernel.h>
  17#include <linux/math.h>
  18#include <linux/math64.h>
  19#include <linux/module.h>
  20#include <linux/overflow.h>
  21#include <linux/pinctrl/consumer.h>
  22#include <linux/platform_device.h>
  23#include <linux/pm_runtime.h>
  24#include <linux/slab.h>
  25#include <linux/spi/spi.h>
  26#include <linux/types.h>
  27#include <linux/of.h>
 
  28#include <linux/property.h>
  29
  30#include <linux/dma/imx-dma.h>
  31
  32#define DRIVER_NAME "spi_imx"
  33
  34static bool use_dma = true;
  35module_param(use_dma, bool, 0644);
  36MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
  37
  38/* define polling limits */
  39static unsigned int polling_limit_us = 30;
  40module_param(polling_limit_us, uint, 0664);
  41MODULE_PARM_DESC(polling_limit_us,
  42		 "time in us to run a transfer in polling mode\n");
  43
  44#define MXC_RPM_TIMEOUT		2000 /* 2000ms */
  45
  46#define MXC_CSPIRXDATA		0x00
  47#define MXC_CSPITXDATA		0x04
  48#define MXC_CSPICTRL		0x08
  49#define MXC_CSPIINT		0x0c
  50#define MXC_RESET		0x1c
  51
  52/* generic defines to abstract from the different register layouts */
  53#define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
  54#define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
  55#define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
  56
  57/* The maximum bytes that a sdma BD can transfer. */
  58#define MAX_SDMA_BD_BYTES (1 << 15)
  59#define MX51_ECSPI_CTRL_MAX_BURST	512
  60/* The maximum bytes that IMX53_ECSPI can transfer in target mode.*/
  61#define MX53_MAX_TRANSFER_BYTES		512
  62
  63enum spi_imx_devtype {
  64	IMX1_CSPI,
  65	IMX21_CSPI,
  66	IMX27_CSPI,
  67	IMX31_CSPI,
  68	IMX35_CSPI,	/* CSPI on all i.mx except above */
  69	IMX51_ECSPI,	/* ECSPI on i.mx51 */
  70	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
  71};
  72
  73struct spi_imx_data;
  74
  75struct spi_imx_devtype_data {
  76	void (*intctrl)(struct spi_imx_data *spi_imx, int enable);
  77	int (*prepare_message)(struct spi_imx_data *spi_imx, struct spi_message *msg);
  78	int (*prepare_transfer)(struct spi_imx_data *spi_imx, struct spi_device *spi,
  79				struct spi_transfer *t);
  80	void (*trigger)(struct spi_imx_data *spi_imx);
  81	int (*rx_available)(struct spi_imx_data *spi_imx);
  82	void (*reset)(struct spi_imx_data *spi_imx);
  83	void (*setup_wml)(struct spi_imx_data *spi_imx);
  84	void (*disable)(struct spi_imx_data *spi_imx);
  85	bool has_dmamode;
  86	bool has_targetmode;
  87	unsigned int fifo_size;
  88	bool dynamic_burst;
  89	/*
  90	 * ERR009165 fixed or not:
  91	 * https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf
  92	 */
  93	bool tx_glitch_fixed;
  94	enum spi_imx_devtype devtype;
  95};
  96
  97struct spi_imx_data {
  98	struct spi_controller *controller;
  99	struct device *dev;
 100
 101	struct completion xfer_done;
 102	void __iomem *base;
 103	unsigned long base_phys;
 104
 105	struct clk *clk_per;
 106	struct clk *clk_ipg;
 107	unsigned long spi_clk;
 108	unsigned int spi_bus_clk;
 109
 110	unsigned int bits_per_word;
 111	unsigned int spi_drctl;
 112
 113	unsigned int count, remainder;
 114	void (*tx)(struct spi_imx_data *spi_imx);
 115	void (*rx)(struct spi_imx_data *spi_imx);
 116	void *rx_buf;
 117	const void *tx_buf;
 118	unsigned int txfifo; /* number of words pushed in tx FIFO */
 119	unsigned int dynamic_burst;
 120	bool rx_only;
 121
 122	/* Target mode */
 123	bool target_mode;
 124	bool target_aborted;
 125	unsigned int target_burst;
 126
 127	/* DMA */
 128	bool usedma;
 129	u32 wml;
 130	struct completion dma_rx_completion;
 131	struct completion dma_tx_completion;
 132
 133	const struct spi_imx_devtype_data *devtype_data;
 134};
 135
 136static inline int is_imx27_cspi(struct spi_imx_data *d)
 137{
 138	return d->devtype_data->devtype == IMX27_CSPI;
 139}
 140
 141static inline int is_imx35_cspi(struct spi_imx_data *d)
 142{
 143	return d->devtype_data->devtype == IMX35_CSPI;
 144}
 145
 146static inline int is_imx51_ecspi(struct spi_imx_data *d)
 147{
 148	return d->devtype_data->devtype == IMX51_ECSPI;
 149}
 150
 151static inline int is_imx53_ecspi(struct spi_imx_data *d)
 152{
 153	return d->devtype_data->devtype == IMX53_ECSPI;
 154}
 155
 156#define MXC_SPI_BUF_RX(type)						\
 157static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
 158{									\
 159	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
 160									\
 161	if (spi_imx->rx_buf) {						\
 162		*(type *)spi_imx->rx_buf = val;				\
 163		spi_imx->rx_buf += sizeof(type);			\
 164	}								\
 165									\
 166	spi_imx->remainder -= sizeof(type);				\
 167}
 168
 169#define MXC_SPI_BUF_TX(type)						\
 170static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
 171{									\
 172	type val = 0;							\
 173									\
 174	if (spi_imx->tx_buf) {						\
 175		val = *(type *)spi_imx->tx_buf;				\
 176		spi_imx->tx_buf += sizeof(type);			\
 177	}								\
 178									\
 179	spi_imx->count -= sizeof(type);					\
 180									\
 181	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
 182}
 183
 184MXC_SPI_BUF_RX(u8)
 185MXC_SPI_BUF_TX(u8)
 186MXC_SPI_BUF_RX(u16)
 187MXC_SPI_BUF_TX(u16)
 188MXC_SPI_BUF_RX(u32)
 189MXC_SPI_BUF_TX(u32)
 190
 191/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 192 * (which is currently not the case in this driver)
 193 */
 194static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 195	256, 384, 512, 768, 1024};
 196
 197/* MX21, MX27 */
 198static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 199		unsigned int fspi, unsigned int max, unsigned int *fres)
 200{
 201	int i;
 202
 203	for (i = 2; i < max; i++)
 204		if (fspi * mxc_clkdivs[i] >= fin)
 205			break;
 206
 207	*fres = fin / mxc_clkdivs[i];
 208	return i;
 209}
 210
 211/* MX1, MX31, MX35, MX51 CSPI */
 212static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 213		unsigned int fspi, unsigned int *fres)
 214{
 215	int i, div = 4;
 216
 217	for (i = 0; i < 7; i++) {
 218		if (fspi * div >= fin)
 219			goto out;
 220		div <<= 1;
 221	}
 222
 223out:
 224	*fres = fin / div;
 225	return i;
 226}
 227
 228static int spi_imx_bytes_per_word(const int bits_per_word)
 229{
 230	if (bits_per_word <= 8)
 231		return 1;
 232	else if (bits_per_word <= 16)
 233		return 2;
 234	else
 235		return 4;
 236}
 237
 238static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device *spi,
 239			 struct spi_transfer *transfer)
 240{
 241	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
 242
 243	if (!use_dma || controller->fallback)
 244		return false;
 245
 246	if (!controller->dma_rx)
 247		return false;
 248
 249	if (spi_imx->target_mode)
 250		return false;
 251
 252	if (transfer->len < spi_imx->devtype_data->fifo_size)
 253		return false;
 254
 255	spi_imx->dynamic_burst = 0;
 256
 257	return true;
 258}
 259
 260/*
 261 * Note the number of natively supported chip selects for MX51 is 4. Some
 262 * devices may have less actual SS pins but the register map supports 4. When
 263 * using gpio chip selects the cs values passed into the macros below can go
 264 * outside the range 0 - 3. We therefore need to limit the cs value to avoid
 265 * corrupting bits outside the allocated locations.
 266 *
 267 * The simplest way to do this is to just mask the cs bits to 2 bits. This
 268 * still allows all 4 native chip selects to work as well as gpio chip selects
 269 * (which can use any of the 4 chip select configurations).
 270 */
 271
 272#define MX51_ECSPI_CTRL		0x08
 273#define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
 274#define MX51_ECSPI_CTRL_XCH		(1 <<  2)
 275#define MX51_ECSPI_CTRL_SMC		(1 << 3)
 276#define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
 277#define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
 278#define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
 279#define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 280#define MX51_ECSPI_CTRL_CS(cs)		((cs & 3) << 18)
 281#define MX51_ECSPI_CTRL_BL_OFFSET	20
 282#define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
 283
 284#define MX51_ECSPI_CONFIG	0x0c
 285#define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs & 3) +  0))
 286#define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs & 3) +  4))
 287#define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs & 3) +  8))
 288#define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs & 3) + 12))
 289#define MX51_ECSPI_CONFIG_DATACTL(cs)	(1 << ((cs & 3) + 16))
 290#define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs & 3) + 20))
 291
 292#define MX51_ECSPI_INT		0x10
 293#define MX51_ECSPI_INT_TEEN		(1 <<  0)
 294#define MX51_ECSPI_INT_RREN		(1 <<  3)
 295#define MX51_ECSPI_INT_RDREN		(1 <<  4)
 296
 297#define MX51_ECSPI_DMA		0x14
 298#define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
 299#define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
 300#define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
 301
 302#define MX51_ECSPI_DMA_TEDEN		(1 << 7)
 303#define MX51_ECSPI_DMA_RXDEN		(1 << 23)
 304#define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
 305
 306#define MX51_ECSPI_STAT		0x18
 307#define MX51_ECSPI_STAT_RR		(1 <<  3)
 308
 309#define MX51_ECSPI_PERIOD	0x1c
 310#define MX51_ECSPI_PERIOD_MASK		0x7fff
 311/*
 312 * As measured on the i.MX6, the SPI host controller inserts a 4 SPI-Clock
 313 * (SCLK) delay after each burst if the PERIOD reg is 0x0. This value will be
 314 * called MX51_ECSPI_PERIOD_MIN_DELAY_SCK.
 315 *
 316 * If the PERIOD register is != 0, the controller inserts a delay of
 317 * MX51_ECSPI_PERIOD_MIN_DELAY_SCK + register value + 1 SCLK after each burst.
 318 */
 319#define MX51_ECSPI_PERIOD_MIN_DELAY_SCK 4
 320
 321#define MX51_ECSPI_TESTREG	0x20
 322#define MX51_ECSPI_TESTREG_LBC	BIT(31)
 323
 324static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
 325{
 326	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
 327
 328	if (spi_imx->rx_buf) {
 329#ifdef __LITTLE_ENDIAN
 330		unsigned int bytes_per_word;
 331
 332		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 333		if (bytes_per_word == 1)
 334			swab32s(&val);
 335		else if (bytes_per_word == 2)
 336			swahw32s(&val);
 337#endif
 338		*(u32 *)spi_imx->rx_buf = val;
 339		spi_imx->rx_buf += sizeof(u32);
 340	}
 341
 342	spi_imx->remainder -= sizeof(u32);
 343}
 344
 345static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
 346{
 347	int unaligned;
 348	u32 val;
 349
 350	unaligned = spi_imx->remainder % 4;
 351
 352	if (!unaligned) {
 353		spi_imx_buf_rx_swap_u32(spi_imx);
 354		return;
 355	}
 356
 357	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 358		spi_imx_buf_rx_u16(spi_imx);
 359		return;
 360	}
 361
 362	val = readl(spi_imx->base + MXC_CSPIRXDATA);
 363
 364	while (unaligned--) {
 365		if (spi_imx->rx_buf) {
 366			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
 367			spi_imx->rx_buf++;
 368		}
 369		spi_imx->remainder--;
 370	}
 371}
 372
 373static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
 374{
 375	u32 val = 0;
 376#ifdef __LITTLE_ENDIAN
 377	unsigned int bytes_per_word;
 378#endif
 379
 380	if (spi_imx->tx_buf) {
 381		val = *(u32 *)spi_imx->tx_buf;
 382		spi_imx->tx_buf += sizeof(u32);
 383	}
 384
 385	spi_imx->count -= sizeof(u32);
 386#ifdef __LITTLE_ENDIAN
 387	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 388
 389	if (bytes_per_word == 1)
 390		swab32s(&val);
 391	else if (bytes_per_word == 2)
 392		swahw32s(&val);
 393#endif
 394	writel(val, spi_imx->base + MXC_CSPITXDATA);
 395}
 396
 397static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
 398{
 399	int unaligned;
 400	u32 val = 0;
 401
 402	unaligned = spi_imx->count % 4;
 403
 404	if (!unaligned) {
 405		spi_imx_buf_tx_swap_u32(spi_imx);
 406		return;
 407	}
 408
 409	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 410		spi_imx_buf_tx_u16(spi_imx);
 411		return;
 412	}
 413
 414	while (unaligned--) {
 415		if (spi_imx->tx_buf) {
 416			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
 417			spi_imx->tx_buf++;
 418		}
 419		spi_imx->count--;
 420	}
 421
 422	writel(val, spi_imx->base + MXC_CSPITXDATA);
 423}
 424
 425static void mx53_ecspi_rx_target(struct spi_imx_data *spi_imx)
 426{
 427	u32 val = ioread32be(spi_imx->base + MXC_CSPIRXDATA);
 428
 429	if (spi_imx->rx_buf) {
 430		int n_bytes = spi_imx->target_burst % sizeof(val);
 431
 432		if (!n_bytes)
 433			n_bytes = sizeof(val);
 434
 435		memcpy(spi_imx->rx_buf,
 436		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
 437
 438		spi_imx->rx_buf += n_bytes;
 439		spi_imx->target_burst -= n_bytes;
 440	}
 441
 442	spi_imx->remainder -= sizeof(u32);
 443}
 444
 445static void mx53_ecspi_tx_target(struct spi_imx_data *spi_imx)
 446{
 447	u32 val = 0;
 448	int n_bytes = spi_imx->count % sizeof(val);
 449
 450	if (!n_bytes)
 451		n_bytes = sizeof(val);
 452
 453	if (spi_imx->tx_buf) {
 454		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
 455		       spi_imx->tx_buf, n_bytes);
 
 456		spi_imx->tx_buf += n_bytes;
 457	}
 458
 459	spi_imx->count -= n_bytes;
 460
 461	iowrite32be(val, spi_imx->base + MXC_CSPITXDATA);
 462}
 463
 464/* MX51 eCSPI */
 465static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 466				      unsigned int fspi, unsigned int *fres)
 467{
 468	/*
 469	 * there are two 4-bit dividers, the pre-divider divides by
 470	 * $pre, the post-divider by 2^$post
 471	 */
 472	unsigned int pre, post;
 473	unsigned int fin = spi_imx->spi_clk;
 474
 475	fspi = min(fspi, fin);
 476
 477	post = fls(fin) - fls(fspi);
 478	if (fin > fspi << post)
 479		post++;
 480
 481	/* now we have: (fin <= fspi << post) with post being minimal */
 482
 483	post = max(4U, post) - 4;
 484	if (unlikely(post > 0xf)) {
 485		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 486				fspi, fin);
 487		return 0xff;
 488	}
 489
 490	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 491
 492	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 493			__func__, fin, fspi, post, pre);
 494
 495	/* Resulting frequency for the SCLK line. */
 496	*fres = (fin / (pre + 1)) >> post;
 497
 498	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 499		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 500}
 501
 502static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 503{
 504	unsigned int val = 0;
 505
 506	if (enable & MXC_INT_TE)
 507		val |= MX51_ECSPI_INT_TEEN;
 508
 509	if (enable & MXC_INT_RR)
 510		val |= MX51_ECSPI_INT_RREN;
 511
 512	if (enable & MXC_INT_RDR)
 513		val |= MX51_ECSPI_INT_RDREN;
 514
 515	writel(val, spi_imx->base + MX51_ECSPI_INT);
 516}
 517
 518static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 519{
 520	u32 reg;
 521
 522	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 523	reg |= MX51_ECSPI_CTRL_XCH;
 524	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 525}
 526
 527static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
 528{
 529	u32 ctrl;
 530
 531	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 532	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
 533	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 534}
 535
 536static int mx51_ecspi_channel(const struct spi_device *spi)
 537{
 538	if (!spi_get_csgpiod(spi, 0))
 539		return spi_get_chipselect(spi, 0);
 540	return spi->controller->unused_native_cs;
 541}
 542
 543static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
 544				      struct spi_message *msg)
 545{
 546	struct spi_device *spi = msg->spi;
 547	struct spi_transfer *xfer;
 548	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 549	u32 min_speed_hz = ~0U;
 550	u32 testreg, delay;
 551	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 552	u32 current_cfg = cfg;
 553	int channel = mx51_ecspi_channel(spi);
 554
 555	/* set Host or Target mode */
 556	if (spi_imx->target_mode)
 557		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
 558	else
 559		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 560
 561	/*
 562	 * Enable SPI_RDY handling (falling edge/level triggered).
 563	 */
 564	if (spi->mode & SPI_READY)
 565		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
 566
 567	/* set chip select to use */
 568	ctrl |= MX51_ECSPI_CTRL_CS(channel);
 569
 570	/*
 571	 * The ctrl register must be written first, with the EN bit set other
 572	 * registers must not be written to.
 573	 */
 574	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 575
 576	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 577	if (spi->mode & SPI_LOOP)
 578		testreg |= MX51_ECSPI_TESTREG_LBC;
 579	else
 580		testreg &= ~MX51_ECSPI_TESTREG_LBC;
 581	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
 582
 583	/*
 584	 * eCSPI burst completion by Chip Select signal in Target mode
 585	 * is not functional for imx53 Soc, config SPI burst completed when
 586	 * BURST_LENGTH + 1 bits are received
 587	 */
 588	if (spi_imx->target_mode && is_imx53_ecspi(spi_imx))
 589		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(channel);
 590	else
 591		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(channel);
 592
 593	if (spi->mode & SPI_CPOL) {
 594		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(channel);
 595		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(channel);
 596	} else {
 597		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(channel);
 598		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(channel);
 599	}
 600
 601	if (spi->mode & SPI_MOSI_IDLE_LOW)
 602		cfg |= MX51_ECSPI_CONFIG_DATACTL(channel);
 603	else
 604		cfg &= ~MX51_ECSPI_CONFIG_DATACTL(channel);
 605
 606	if (spi->mode & SPI_CS_HIGH)
 607		cfg |= MX51_ECSPI_CONFIG_SSBPOL(channel);
 608	else
 609		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(channel);
 610
 611	if (cfg == current_cfg)
 612		return 0;
 613
 614	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 615
 616	/*
 617	 * Wait until the changes in the configuration register CONFIGREG
 618	 * propagate into the hardware. It takes exactly one tick of the
 619	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
 620	 * effect of the delay it takes for the hardware to apply changes
 621	 * is noticable if the SCLK clock run very slow. In such a case, if
 622	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 623	 * be asserted before the SCLK polarity changes, which would disrupt
 624	 * the SPI communication as the device on the other end would consider
 625	 * the change of SCLK polarity as a clock tick already.
 626	 *
 627	 * Because spi_imx->spi_bus_clk is only set in prepare_message
 628	 * callback, iterate over all the transfers in spi_message, find the
 629	 * one with lowest bus frequency, and use that bus frequency for the
 630	 * delay calculation. In case all transfers have speed_hz == 0, then
 631	 * min_speed_hz is ~0 and the resulting delay is zero.
 632	 */
 633	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
 634		if (!xfer->speed_hz)
 635			continue;
 636		min_speed_hz = min(xfer->speed_hz, min_speed_hz);
 637	}
 638
 639	delay = (2 * 1000000) / min_speed_hz;
 640	if (likely(delay < 10))	/* SCLK is faster than 200 kHz */
 641		udelay(delay);
 642	else			/* SCLK is _very_ slow */
 643		usleep_range(delay, delay + 10);
 644
 645	return 0;
 646}
 647
 648static void mx51_configure_cpha(struct spi_imx_data *spi_imx,
 649				struct spi_device *spi)
 650{
 651	bool cpha = (spi->mode & SPI_CPHA);
 652	bool flip_cpha = (spi->mode & SPI_RX_CPHA_FLIP) && spi_imx->rx_only;
 653	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 654	int channel = mx51_ecspi_channel(spi);
 655
 656	/* Flip cpha logical value iff flip_cpha */
 657	cpha ^= flip_cpha;
 658
 659	if (cpha)
 660		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(channel);
 661	else
 662		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(channel);
 663
 664	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 665}
 666
 667static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
 668				       struct spi_device *spi, struct spi_transfer *t)
 669{
 670	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 671	u64 word_delay_sck;
 672	u32 clk;
 673
 674	/* Clear BL field and set the right value */
 675	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
 676	if (spi_imx->target_mode && is_imx53_ecspi(spi_imx))
 677		ctrl |= (spi_imx->target_burst * 8 - 1)
 678			<< MX51_ECSPI_CTRL_BL_OFFSET;
 679	else {
 680		ctrl |= (spi_imx->bits_per_word - 1)
 681			<< MX51_ECSPI_CTRL_BL_OFFSET;
 682	}
 683
 684	/* set clock speed */
 685	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
 686		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
 687	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
 688	spi_imx->spi_bus_clk = clk;
 689
 690	mx51_configure_cpha(spi_imx, spi);
 691
 692	/*
 693	 * ERR009165: work in XHC mode instead of SMC as PIO on the chips
 694	 * before i.mx6ul.
 695	 */
 696	if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
 697		ctrl |= MX51_ECSPI_CTRL_SMC;
 698	else
 699		ctrl &= ~MX51_ECSPI_CTRL_SMC;
 700
 701	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 702
 703	/* calculate word delay in SPI Clock (SCLK) cycles */
 704	if (t->word_delay.value == 0) {
 705		word_delay_sck = 0;
 706	} else if (t->word_delay.unit == SPI_DELAY_UNIT_SCK) {
 707		word_delay_sck = t->word_delay.value;
 708
 709		if (word_delay_sck <= MX51_ECSPI_PERIOD_MIN_DELAY_SCK)
 710			word_delay_sck = 0;
 711		else if (word_delay_sck <= MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1)
 712			word_delay_sck = 1;
 713		else
 714			word_delay_sck -= MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1;
 715	} else {
 716		int word_delay_ns;
 717
 718		word_delay_ns = spi_delay_to_ns(&t->word_delay, t);
 719		if (word_delay_ns < 0)
 720			return word_delay_ns;
 721
 722		if (word_delay_ns <= mul_u64_u32_div(NSEC_PER_SEC,
 723						     MX51_ECSPI_PERIOD_MIN_DELAY_SCK,
 724						     spi_imx->spi_bus_clk)) {
 725			word_delay_sck = 0;
 726		} else if (word_delay_ns <= mul_u64_u32_div(NSEC_PER_SEC,
 727							    MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1,
 728							    spi_imx->spi_bus_clk)) {
 729			word_delay_sck = 1;
 730		} else {
 731			word_delay_ns -= mul_u64_u32_div(NSEC_PER_SEC,
 732							 MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1,
 733							 spi_imx->spi_bus_clk);
 734
 735			word_delay_sck = DIV_U64_ROUND_UP((u64)word_delay_ns * spi_imx->spi_bus_clk,
 736							  NSEC_PER_SEC);
 737		}
 738	}
 739
 740	if (!FIELD_FIT(MX51_ECSPI_PERIOD_MASK, word_delay_sck))
 741		return -EINVAL;
 742
 743	writel(FIELD_PREP(MX51_ECSPI_PERIOD_MASK, word_delay_sck),
 744	       spi_imx->base + MX51_ECSPI_PERIOD);
 745
 746	return 0;
 747}
 748
 749static void mx51_setup_wml(struct spi_imx_data *spi_imx)
 750{
 751	u32 tx_wml = 0;
 752
 753	if (spi_imx->devtype_data->tx_glitch_fixed)
 754		tx_wml = spi_imx->wml;
 755	/*
 756	 * Configure the DMA register: setup the watermark
 757	 * and enable DMA request.
 758	 */
 759	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
 760		MX51_ECSPI_DMA_TX_WML(tx_wml) |
 761		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 762		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 763		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 764}
 765
 766static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 767{
 768	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 769}
 770
 771static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 772{
 773	/* drain receive buffer */
 774	while (mx51_ecspi_rx_available(spi_imx))
 775		readl(spi_imx->base + MXC_CSPIRXDATA);
 776}
 777
 778#define MX31_INTREG_TEEN	(1 << 0)
 779#define MX31_INTREG_RREN	(1 << 3)
 780
 781#define MX31_CSPICTRL_ENABLE	(1 << 0)
 782#define MX31_CSPICTRL_HOST	(1 << 1)
 783#define MX31_CSPICTRL_XCH	(1 << 2)
 784#define MX31_CSPICTRL_SMC	(1 << 3)
 785#define MX31_CSPICTRL_POL	(1 << 4)
 786#define MX31_CSPICTRL_PHA	(1 << 5)
 787#define MX31_CSPICTRL_SSCTL	(1 << 6)
 788#define MX31_CSPICTRL_SSPOL	(1 << 7)
 789#define MX31_CSPICTRL_BC_SHIFT	8
 790#define MX35_CSPICTRL_BL_SHIFT	20
 791#define MX31_CSPICTRL_CS_SHIFT	24
 792#define MX35_CSPICTRL_CS_SHIFT	12
 793#define MX31_CSPICTRL_DR_SHIFT	16
 794
 795#define MX31_CSPI_DMAREG	0x10
 796#define MX31_DMAREG_RH_DEN	(1<<4)
 797#define MX31_DMAREG_TH_DEN	(1<<1)
 798
 799#define MX31_CSPISTATUS		0x14
 800#define MX31_STATUS_RR		(1 << 3)
 801
 802#define MX31_CSPI_TESTREG	0x1C
 803#define MX31_TEST_LBC		(1 << 14)
 804
 805/* These functions also work for the i.MX35, but be aware that
 806 * the i.MX35 has a slightly different register layout for bits
 807 * we do not use here.
 808 */
 809static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 810{
 811	unsigned int val = 0;
 812
 813	if (enable & MXC_INT_TE)
 814		val |= MX31_INTREG_TEEN;
 815	if (enable & MXC_INT_RR)
 816		val |= MX31_INTREG_RREN;
 817
 818	writel(val, spi_imx->base + MXC_CSPIINT);
 819}
 820
 821static void mx31_trigger(struct spi_imx_data *spi_imx)
 822{
 823	unsigned int reg;
 824
 825	reg = readl(spi_imx->base + MXC_CSPICTRL);
 826	reg |= MX31_CSPICTRL_XCH;
 827	writel(reg, spi_imx->base + MXC_CSPICTRL);
 828}
 829
 830static int mx31_prepare_message(struct spi_imx_data *spi_imx,
 831				struct spi_message *msg)
 832{
 833	return 0;
 834}
 835
 836static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
 837				 struct spi_device *spi, struct spi_transfer *t)
 838{
 839	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_HOST;
 840	unsigned int clk;
 841
 842	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
 843		MX31_CSPICTRL_DR_SHIFT;
 844	spi_imx->spi_bus_clk = clk;
 845
 846	if (is_imx35_cspi(spi_imx)) {
 847		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
 848		reg |= MX31_CSPICTRL_SSCTL;
 849	} else {
 850		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
 851	}
 852
 853	if (spi->mode & SPI_CPHA)
 854		reg |= MX31_CSPICTRL_PHA;
 855	if (spi->mode & SPI_CPOL)
 856		reg |= MX31_CSPICTRL_POL;
 857	if (spi->mode & SPI_CS_HIGH)
 858		reg |= MX31_CSPICTRL_SSPOL;
 859	if (!spi_get_csgpiod(spi, 0))
 860		reg |= (spi_get_chipselect(spi, 0)) <<
 861			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 862						  MX31_CSPICTRL_CS_SHIFT);
 863
 864	if (spi_imx->usedma)
 865		reg |= MX31_CSPICTRL_SMC;
 866
 867	writel(reg, spi_imx->base + MXC_CSPICTRL);
 868
 869	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
 870	if (spi->mode & SPI_LOOP)
 871		reg |= MX31_TEST_LBC;
 872	else
 873		reg &= ~MX31_TEST_LBC;
 874	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 875
 876	if (spi_imx->usedma) {
 877		/*
 878		 * configure DMA requests when RXFIFO is half full and
 879		 * when TXFIFO is half empty
 880		 */
 881		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
 882			spi_imx->base + MX31_CSPI_DMAREG);
 883	}
 884
 885	return 0;
 886}
 887
 888static int mx31_rx_available(struct spi_imx_data *spi_imx)
 889{
 890	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 891}
 892
 893static void mx31_reset(struct spi_imx_data *spi_imx)
 894{
 895	/* drain receive buffer */
 896	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 897		readl(spi_imx->base + MXC_CSPIRXDATA);
 898}
 899
 900#define MX21_INTREG_RR		(1 << 4)
 901#define MX21_INTREG_TEEN	(1 << 9)
 902#define MX21_INTREG_RREN	(1 << 13)
 903
 904#define MX21_CSPICTRL_POL	(1 << 5)
 905#define MX21_CSPICTRL_PHA	(1 << 6)
 906#define MX21_CSPICTRL_SSPOL	(1 << 8)
 907#define MX21_CSPICTRL_XCH	(1 << 9)
 908#define MX21_CSPICTRL_ENABLE	(1 << 10)
 909#define MX21_CSPICTRL_HOST	(1 << 11)
 910#define MX21_CSPICTRL_DR_SHIFT	14
 911#define MX21_CSPICTRL_CS_SHIFT	19
 912
 913static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 914{
 915	unsigned int val = 0;
 916
 917	if (enable & MXC_INT_TE)
 918		val |= MX21_INTREG_TEEN;
 919	if (enable & MXC_INT_RR)
 920		val |= MX21_INTREG_RREN;
 921
 922	writel(val, spi_imx->base + MXC_CSPIINT);
 923}
 924
 925static void mx21_trigger(struct spi_imx_data *spi_imx)
 926{
 927	unsigned int reg;
 928
 929	reg = readl(spi_imx->base + MXC_CSPICTRL);
 930	reg |= MX21_CSPICTRL_XCH;
 931	writel(reg, spi_imx->base + MXC_CSPICTRL);
 932}
 933
 934static int mx21_prepare_message(struct spi_imx_data *spi_imx,
 935				struct spi_message *msg)
 936{
 937	return 0;
 938}
 939
 940static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
 941				 struct spi_device *spi, struct spi_transfer *t)
 942{
 943	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_HOST;
 944	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 945	unsigned int clk;
 946
 947	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
 948		<< MX21_CSPICTRL_DR_SHIFT;
 949	spi_imx->spi_bus_clk = clk;
 950
 951	reg |= spi_imx->bits_per_word - 1;
 952
 953	if (spi->mode & SPI_CPHA)
 954		reg |= MX21_CSPICTRL_PHA;
 955	if (spi->mode & SPI_CPOL)
 956		reg |= MX21_CSPICTRL_POL;
 957	if (spi->mode & SPI_CS_HIGH)
 958		reg |= MX21_CSPICTRL_SSPOL;
 959	if (!spi_get_csgpiod(spi, 0))
 960		reg |= spi_get_chipselect(spi, 0) << MX21_CSPICTRL_CS_SHIFT;
 961
 962	writel(reg, spi_imx->base + MXC_CSPICTRL);
 963
 964	return 0;
 965}
 966
 967static int mx21_rx_available(struct spi_imx_data *spi_imx)
 968{
 969	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 970}
 971
 972static void mx21_reset(struct spi_imx_data *spi_imx)
 973{
 974	writel(1, spi_imx->base + MXC_RESET);
 975}
 976
 977#define MX1_INTREG_RR		(1 << 3)
 978#define MX1_INTREG_TEEN		(1 << 8)
 979#define MX1_INTREG_RREN		(1 << 11)
 980
 981#define MX1_CSPICTRL_POL	(1 << 4)
 982#define MX1_CSPICTRL_PHA	(1 << 5)
 983#define MX1_CSPICTRL_XCH	(1 << 8)
 984#define MX1_CSPICTRL_ENABLE	(1 << 9)
 985#define MX1_CSPICTRL_HOST	(1 << 10)
 986#define MX1_CSPICTRL_DR_SHIFT	13
 987
 988static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 989{
 990	unsigned int val = 0;
 991
 992	if (enable & MXC_INT_TE)
 993		val |= MX1_INTREG_TEEN;
 994	if (enable & MXC_INT_RR)
 995		val |= MX1_INTREG_RREN;
 996
 997	writel(val, spi_imx->base + MXC_CSPIINT);
 998}
 999
1000static void mx1_trigger(struct spi_imx_data *spi_imx)
1001{
1002	unsigned int reg;
1003
1004	reg = readl(spi_imx->base + MXC_CSPICTRL);
1005	reg |= MX1_CSPICTRL_XCH;
1006	writel(reg, spi_imx->base + MXC_CSPICTRL);
1007}
1008
1009static int mx1_prepare_message(struct spi_imx_data *spi_imx,
1010			       struct spi_message *msg)
1011{
1012	return 0;
1013}
1014
1015static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
1016				struct spi_device *spi, struct spi_transfer *t)
1017{
1018	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_HOST;
1019	unsigned int clk;
1020
1021	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
1022		MX1_CSPICTRL_DR_SHIFT;
1023	spi_imx->spi_bus_clk = clk;
1024
1025	reg |= spi_imx->bits_per_word - 1;
1026
1027	if (spi->mode & SPI_CPHA)
1028		reg |= MX1_CSPICTRL_PHA;
1029	if (spi->mode & SPI_CPOL)
1030		reg |= MX1_CSPICTRL_POL;
1031
1032	writel(reg, spi_imx->base + MXC_CSPICTRL);
1033
1034	return 0;
1035}
1036
1037static int mx1_rx_available(struct spi_imx_data *spi_imx)
1038{
1039	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
1040}
1041
1042static void mx1_reset(struct spi_imx_data *spi_imx)
1043{
1044	writel(1, spi_imx->base + MXC_RESET);
1045}
1046
1047static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
1048	.intctrl = mx1_intctrl,
1049	.prepare_message = mx1_prepare_message,
1050	.prepare_transfer = mx1_prepare_transfer,
1051	.trigger = mx1_trigger,
1052	.rx_available = mx1_rx_available,
1053	.reset = mx1_reset,
1054	.fifo_size = 8,
1055	.has_dmamode = false,
1056	.dynamic_burst = false,
1057	.has_targetmode = false,
1058	.devtype = IMX1_CSPI,
1059};
1060
1061static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
1062	.intctrl = mx21_intctrl,
1063	.prepare_message = mx21_prepare_message,
1064	.prepare_transfer = mx21_prepare_transfer,
1065	.trigger = mx21_trigger,
1066	.rx_available = mx21_rx_available,
1067	.reset = mx21_reset,
1068	.fifo_size = 8,
1069	.has_dmamode = false,
1070	.dynamic_burst = false,
1071	.has_targetmode = false,
1072	.devtype = IMX21_CSPI,
1073};
1074
1075static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
1076	/* i.mx27 cspi shares the functions with i.mx21 one */
1077	.intctrl = mx21_intctrl,
1078	.prepare_message = mx21_prepare_message,
1079	.prepare_transfer = mx21_prepare_transfer,
1080	.trigger = mx21_trigger,
1081	.rx_available = mx21_rx_available,
1082	.reset = mx21_reset,
1083	.fifo_size = 8,
1084	.has_dmamode = false,
1085	.dynamic_burst = false,
1086	.has_targetmode = false,
1087	.devtype = IMX27_CSPI,
1088};
1089
1090static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
1091	.intctrl = mx31_intctrl,
1092	.prepare_message = mx31_prepare_message,
1093	.prepare_transfer = mx31_prepare_transfer,
1094	.trigger = mx31_trigger,
1095	.rx_available = mx31_rx_available,
1096	.reset = mx31_reset,
1097	.fifo_size = 8,
1098	.has_dmamode = false,
1099	.dynamic_burst = false,
1100	.has_targetmode = false,
1101	.devtype = IMX31_CSPI,
1102};
1103
1104static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
1105	/* i.mx35 and later cspi shares the functions with i.mx31 one */
1106	.intctrl = mx31_intctrl,
1107	.prepare_message = mx31_prepare_message,
1108	.prepare_transfer = mx31_prepare_transfer,
1109	.trigger = mx31_trigger,
1110	.rx_available = mx31_rx_available,
1111	.reset = mx31_reset,
1112	.fifo_size = 8,
1113	.has_dmamode = false,
1114	.dynamic_burst = false,
1115	.has_targetmode = false,
1116	.devtype = IMX35_CSPI,
1117};
1118
1119static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
1120	.intctrl = mx51_ecspi_intctrl,
1121	.prepare_message = mx51_ecspi_prepare_message,
1122	.prepare_transfer = mx51_ecspi_prepare_transfer,
1123	.trigger = mx51_ecspi_trigger,
1124	.rx_available = mx51_ecspi_rx_available,
1125	.reset = mx51_ecspi_reset,
1126	.setup_wml = mx51_setup_wml,
1127	.fifo_size = 64,
1128	.has_dmamode = true,
1129	.dynamic_burst = true,
1130	.has_targetmode = true,
1131	.disable = mx51_ecspi_disable,
1132	.devtype = IMX51_ECSPI,
1133};
1134
1135static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1136	.intctrl = mx51_ecspi_intctrl,
1137	.prepare_message = mx51_ecspi_prepare_message,
1138	.prepare_transfer = mx51_ecspi_prepare_transfer,
1139	.trigger = mx51_ecspi_trigger,
1140	.rx_available = mx51_ecspi_rx_available,
1141	.reset = mx51_ecspi_reset,
1142	.fifo_size = 64,
1143	.has_dmamode = true,
1144	.has_targetmode = true,
1145	.disable = mx51_ecspi_disable,
1146	.devtype = IMX53_ECSPI,
1147};
1148
1149static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
1150	.intctrl = mx51_ecspi_intctrl,
1151	.prepare_message = mx51_ecspi_prepare_message,
1152	.prepare_transfer = mx51_ecspi_prepare_transfer,
1153	.trigger = mx51_ecspi_trigger,
1154	.rx_available = mx51_ecspi_rx_available,
1155	.reset = mx51_ecspi_reset,
1156	.setup_wml = mx51_setup_wml,
1157	.fifo_size = 64,
1158	.has_dmamode = true,
1159	.dynamic_burst = true,
1160	.has_targetmode = true,
1161	.tx_glitch_fixed = true,
1162	.disable = mx51_ecspi_disable,
1163	.devtype = IMX51_ECSPI,
1164};
1165
1166static const struct of_device_id spi_imx_dt_ids[] = {
1167	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1168	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1169	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1170	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1171	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1172	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1173	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1174	{ .compatible = "fsl,imx6ul-ecspi", .data = &imx6ul_ecspi_devtype_data, },
1175	{ /* sentinel */ }
1176};
1177MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1178
1179static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1180{
1181	u32 ctrl;
1182
1183	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1184	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1185	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1186	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1187}
1188
1189static void spi_imx_push(struct spi_imx_data *spi_imx)
1190{
1191	unsigned int burst_len;
1192
1193	/*
1194	 * Reload the FIFO when the remaining bytes to be transferred in the
1195	 * current burst is 0. This only applies when bits_per_word is a
1196	 * multiple of 8.
1197	 */
1198	if (!spi_imx->remainder) {
1199		if (spi_imx->dynamic_burst) {
1200
1201			/* We need to deal unaligned data first */
1202			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1203
1204			if (!burst_len)
1205				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1206
1207			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1208
1209			spi_imx->remainder = burst_len;
1210		} else {
1211			spi_imx->remainder = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1212		}
1213	}
1214
1215	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1216		if (!spi_imx->count)
1217			break;
1218		if (spi_imx->dynamic_burst &&
1219		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder, 4))
1220			break;
1221		spi_imx->tx(spi_imx);
1222		spi_imx->txfifo++;
1223	}
1224
1225	if (!spi_imx->target_mode)
1226		spi_imx->devtype_data->trigger(spi_imx);
1227}
1228
1229static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1230{
1231	struct spi_imx_data *spi_imx = dev_id;
1232
1233	while (spi_imx->txfifo &&
1234	       spi_imx->devtype_data->rx_available(spi_imx)) {
1235		spi_imx->rx(spi_imx);
1236		spi_imx->txfifo--;
1237	}
1238
1239	if (spi_imx->count) {
1240		spi_imx_push(spi_imx);
1241		return IRQ_HANDLED;
1242	}
1243
1244	if (spi_imx->txfifo) {
1245		/* No data left to push, but still waiting for rx data,
1246		 * enable receive data available interrupt.
1247		 */
1248		spi_imx->devtype_data->intctrl(
1249				spi_imx, MXC_INT_RR);
1250		return IRQ_HANDLED;
1251	}
1252
1253	spi_imx->devtype_data->intctrl(spi_imx, 0);
1254	complete(&spi_imx->xfer_done);
1255
1256	return IRQ_HANDLED;
1257}
1258
1259static int spi_imx_dma_configure(struct spi_controller *controller)
1260{
1261	int ret;
1262	enum dma_slave_buswidth buswidth;
1263	struct dma_slave_config rx = {}, tx = {};
1264	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1265
1266	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1267	case 4:
1268		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1269		break;
1270	case 2:
1271		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1272		break;
1273	case 1:
1274		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1275		break;
1276	default:
1277		return -EINVAL;
1278	}
1279
1280	tx.direction = DMA_MEM_TO_DEV;
1281	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1282	tx.dst_addr_width = buswidth;
1283	tx.dst_maxburst = spi_imx->wml;
1284	ret = dmaengine_slave_config(controller->dma_tx, &tx);
1285	if (ret) {
1286		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1287		return ret;
1288	}
1289
1290	rx.direction = DMA_DEV_TO_MEM;
1291	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1292	rx.src_addr_width = buswidth;
1293	rx.src_maxburst = spi_imx->wml;
1294	ret = dmaengine_slave_config(controller->dma_rx, &rx);
1295	if (ret) {
1296		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1297		return ret;
1298	}
1299
1300	return 0;
1301}
1302
1303static int spi_imx_setupxfer(struct spi_device *spi,
1304				 struct spi_transfer *t)
1305{
1306	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1307
1308	if (!t)
1309		return 0;
1310
1311	if (!t->speed_hz) {
1312		if (!spi->max_speed_hz) {
1313			dev_err(&spi->dev, "no speed_hz provided!\n");
1314			return -EINVAL;
1315		}
1316		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1317		spi_imx->spi_bus_clk = spi->max_speed_hz;
1318	} else
1319		spi_imx->spi_bus_clk = t->speed_hz;
1320
1321	spi_imx->bits_per_word = t->bits_per_word;
1322	spi_imx->count = t->len;
1323
1324	/*
1325	 * Initialize the functions for transfer. To transfer non byte-aligned
1326	 * words, we have to use multiple word-size bursts. To insert word
1327	 * delay, the burst size has to equal the word size. We can't use
1328	 * dynamic_burst in these cases.
1329	 */
1330	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->target_mode &&
1331	    !(spi->mode & SPI_CS_WORD) &&
1332	    !(t->word_delay.value) &&
1333	    (spi_imx->bits_per_word == 8 ||
1334	    spi_imx->bits_per_word == 16 ||
1335	    spi_imx->bits_per_word == 32)) {
1336
1337		spi_imx->rx = spi_imx_buf_rx_swap;
1338		spi_imx->tx = spi_imx_buf_tx_swap;
1339		spi_imx->dynamic_burst = 1;
1340
1341	} else {
1342		if (spi_imx->bits_per_word <= 8) {
1343			spi_imx->rx = spi_imx_buf_rx_u8;
1344			spi_imx->tx = spi_imx_buf_tx_u8;
1345		} else if (spi_imx->bits_per_word <= 16) {
1346			spi_imx->rx = spi_imx_buf_rx_u16;
1347			spi_imx->tx = spi_imx_buf_tx_u16;
1348		} else {
1349			spi_imx->rx = spi_imx_buf_rx_u32;
1350			spi_imx->tx = spi_imx_buf_tx_u32;
1351		}
1352		spi_imx->dynamic_burst = 0;
1353	}
1354
1355	if (spi_imx_can_dma(spi_imx->controller, spi, t))
1356		spi_imx->usedma = true;
1357	else
1358		spi_imx->usedma = false;
1359
1360	spi_imx->rx_only = ((t->tx_buf == NULL)
1361			|| (t->tx_buf == spi->controller->dummy_tx));
1362
1363	if (is_imx53_ecspi(spi_imx) && spi_imx->target_mode) {
1364		spi_imx->rx = mx53_ecspi_rx_target;
1365		spi_imx->tx = mx53_ecspi_tx_target;
1366		spi_imx->target_burst = t->len;
1367	}
1368
1369	spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
1370
1371	return 0;
1372}
1373
1374static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1375{
1376	struct spi_controller *controller = spi_imx->controller;
1377
1378	if (controller->dma_rx) {
1379		dma_release_channel(controller->dma_rx);
1380		controller->dma_rx = NULL;
1381	}
1382
1383	if (controller->dma_tx) {
1384		dma_release_channel(controller->dma_tx);
1385		controller->dma_tx = NULL;
1386	}
1387}
1388
1389static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1390			     struct spi_controller *controller)
1391{
1392	int ret;
1393
1394	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1395
1396	/* Prepare for TX DMA: */
1397	controller->dma_tx = dma_request_chan(dev, "tx");
1398	if (IS_ERR(controller->dma_tx)) {
1399		ret = PTR_ERR(controller->dma_tx);
1400		dev_err_probe(dev, ret, "can't get the TX DMA channel!\n");
1401		controller->dma_tx = NULL;
1402		goto err;
1403	}
1404
1405	/* Prepare for RX : */
1406	controller->dma_rx = dma_request_chan(dev, "rx");
1407	if (IS_ERR(controller->dma_rx)) {
1408		ret = PTR_ERR(controller->dma_rx);
1409		dev_err_probe(dev, ret, "can't get the RX DMA channel!\n");
1410		controller->dma_rx = NULL;
1411		goto err;
1412	}
1413
1414	init_completion(&spi_imx->dma_rx_completion);
1415	init_completion(&spi_imx->dma_tx_completion);
1416	controller->can_dma = spi_imx_can_dma;
1417	controller->max_dma_len = MAX_SDMA_BD_BYTES;
1418	spi_imx->controller->flags = SPI_CONTROLLER_MUST_RX |
1419					 SPI_CONTROLLER_MUST_TX;
1420
1421	return 0;
1422err:
1423	spi_imx_sdma_exit(spi_imx);
1424	return ret;
1425}
1426
1427static void spi_imx_dma_rx_callback(void *cookie)
1428{
1429	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1430
1431	complete(&spi_imx->dma_rx_completion);
1432}
1433
1434static void spi_imx_dma_tx_callback(void *cookie)
1435{
1436	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1437
1438	complete(&spi_imx->dma_tx_completion);
1439}
1440
1441static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1442{
1443	unsigned long timeout = 0;
1444
1445	/* Time with actual data transfer and CS change delay related to HW */
1446	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1447
1448	/* Add extra second for scheduler related activities */
1449	timeout += 1;
1450
1451	/* Double calculated timeout */
1452	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1453}
1454
1455static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1456				struct spi_transfer *transfer)
1457{
1458	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1459	unsigned long transfer_timeout;
1460	unsigned long time_left;
1461	struct spi_controller *controller = spi_imx->controller;
1462	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1463	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1464	unsigned int bytes_per_word, i;
1465	int ret;
1466
1467	/* Get the right burst length from the last sg to ensure no tail data */
1468	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1469	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1470		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1471			break;
1472	}
1473	/* Use 1 as wml in case no available burst length got */
1474	if (i == 0)
1475		i = 1;
1476
1477	spi_imx->wml =  i;
1478
1479	ret = spi_imx_dma_configure(controller);
1480	if (ret)
1481		goto dma_failure_no_start;
1482
1483	if (!spi_imx->devtype_data->setup_wml) {
1484		dev_err(spi_imx->dev, "No setup_wml()?\n");
1485		ret = -EINVAL;
1486		goto dma_failure_no_start;
1487	}
1488	spi_imx->devtype_data->setup_wml(spi_imx);
1489
1490	/*
1491	 * The TX DMA setup starts the transfer, so make sure RX is configured
1492	 * before TX.
1493	 */
1494	desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
1495				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1496				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1497	if (!desc_rx) {
1498		ret = -EINVAL;
1499		goto dma_failure_no_start;
1500	}
1501
1502	desc_rx->callback = spi_imx_dma_rx_callback;
1503	desc_rx->callback_param = (void *)spi_imx;
1504	dmaengine_submit(desc_rx);
1505	reinit_completion(&spi_imx->dma_rx_completion);
1506	dma_async_issue_pending(controller->dma_rx);
1507
1508	desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
1509				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1510				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1511	if (!desc_tx) {
1512		dmaengine_terminate_all(controller->dma_tx);
1513		dmaengine_terminate_all(controller->dma_rx);
1514		return -EINVAL;
1515	}
1516
1517	desc_tx->callback = spi_imx_dma_tx_callback;
1518	desc_tx->callback_param = (void *)spi_imx;
1519	dmaengine_submit(desc_tx);
1520	reinit_completion(&spi_imx->dma_tx_completion);
1521	dma_async_issue_pending(controller->dma_tx);
1522
1523	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1524
1525	/* Wait SDMA to finish the data transfer.*/
1526	time_left = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1527						transfer_timeout);
1528	if (!time_left) {
1529		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1530		dmaengine_terminate_all(controller->dma_tx);
1531		dmaengine_terminate_all(controller->dma_rx);
1532		return -ETIMEDOUT;
1533	}
1534
1535	time_left = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1536						transfer_timeout);
1537	if (!time_left) {
1538		dev_err(&controller->dev, "I/O Error in DMA RX\n");
1539		spi_imx->devtype_data->reset(spi_imx);
1540		dmaengine_terminate_all(controller->dma_rx);
1541		return -ETIMEDOUT;
1542	}
1543
1544	return 0;
1545/* fallback to pio */
1546dma_failure_no_start:
1547	transfer->error |= SPI_TRANS_FAIL_NO_START;
1548	return ret;
1549}
1550
1551static int spi_imx_pio_transfer(struct spi_device *spi,
1552				struct spi_transfer *transfer)
1553{
1554	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1555	unsigned long transfer_timeout;
1556	unsigned long time_left;
1557
1558	spi_imx->tx_buf = transfer->tx_buf;
1559	spi_imx->rx_buf = transfer->rx_buf;
1560	spi_imx->count = transfer->len;
1561	spi_imx->txfifo = 0;
1562	spi_imx->remainder = 0;
1563
1564	reinit_completion(&spi_imx->xfer_done);
1565
1566	spi_imx_push(spi_imx);
1567
1568	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1569
1570	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1571
1572	time_left = wait_for_completion_timeout(&spi_imx->xfer_done,
1573						transfer_timeout);
1574	if (!time_left) {
1575		dev_err(&spi->dev, "I/O Error in PIO\n");
1576		spi_imx->devtype_data->reset(spi_imx);
1577		return -ETIMEDOUT;
1578	}
1579
1580	return 0;
1581}
1582
1583static int spi_imx_poll_transfer(struct spi_device *spi,
1584				 struct spi_transfer *transfer)
1585{
1586	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1587	unsigned long timeout;
1588
1589	spi_imx->tx_buf = transfer->tx_buf;
1590	spi_imx->rx_buf = transfer->rx_buf;
1591	spi_imx->count = transfer->len;
1592	spi_imx->txfifo = 0;
1593	spi_imx->remainder = 0;
1594
1595	/* fill in the fifo before timeout calculations if we are
1596	 * interrupted here, then the data is getting transferred by
1597	 * the HW while we are interrupted
1598	 */
1599	spi_imx_push(spi_imx);
1600
1601	timeout = spi_imx_calculate_timeout(spi_imx, transfer->len) + jiffies;
1602	while (spi_imx->txfifo) {
1603		/* RX */
1604		while (spi_imx->txfifo &&
1605		       spi_imx->devtype_data->rx_available(spi_imx)) {
1606			spi_imx->rx(spi_imx);
1607			spi_imx->txfifo--;
1608		}
1609
1610		/* TX */
1611		if (spi_imx->count) {
1612			spi_imx_push(spi_imx);
1613			continue;
1614		}
1615
1616		if (spi_imx->txfifo &&
1617		    time_after(jiffies, timeout)) {
1618
1619			dev_err_ratelimited(&spi->dev,
1620					    "timeout period reached: jiffies: %lu- falling back to interrupt mode\n",
1621					    jiffies - timeout);
1622
1623			/* fall back to interrupt mode */
1624			return spi_imx_pio_transfer(spi, transfer);
1625		}
1626	}
1627
1628	return 0;
1629}
1630
1631static int spi_imx_pio_transfer_target(struct spi_device *spi,
1632				       struct spi_transfer *transfer)
1633{
1634	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1635	int ret = 0;
1636
1637	if (is_imx53_ecspi(spi_imx) &&
1638	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1639		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1640			MX53_MAX_TRANSFER_BYTES);
1641		return -EMSGSIZE;
1642	}
1643
1644	spi_imx->tx_buf = transfer->tx_buf;
1645	spi_imx->rx_buf = transfer->rx_buf;
1646	spi_imx->count = transfer->len;
1647	spi_imx->txfifo = 0;
1648	spi_imx->remainder = 0;
1649
1650	reinit_completion(&spi_imx->xfer_done);
1651	spi_imx->target_aborted = false;
1652
1653	spi_imx_push(spi_imx);
1654
1655	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1656
1657	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1658	    spi_imx->target_aborted) {
1659		dev_dbg(&spi->dev, "interrupted\n");
1660		ret = -EINTR;
1661	}
1662
1663	/* ecspi has a HW issue when works in Target mode,
1664	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1665	 * ECSPI_TXDATA keeps shift out the last word data,
1666	 * so we have to disable ECSPI when in target mode after the
1667	 * transfer completes
1668	 */
1669	if (spi_imx->devtype_data->disable)
1670		spi_imx->devtype_data->disable(spi_imx);
1671
1672	return ret;
1673}
1674
1675static unsigned int spi_imx_transfer_estimate_time_us(struct spi_transfer *transfer)
1676{
1677	u64 result;
1678
1679	result = DIV_U64_ROUND_CLOSEST((u64)USEC_PER_SEC * transfer->len * BITS_PER_BYTE,
1680				       transfer->effective_speed_hz);
1681	if (transfer->word_delay.value) {
1682		unsigned int word_delay_us;
1683		unsigned int words;
1684
1685		words = DIV_ROUND_UP(transfer->len * BITS_PER_BYTE, transfer->bits_per_word);
1686		word_delay_us = DIV_ROUND_CLOSEST(spi_delay_to_ns(&transfer->word_delay, transfer),
1687						  NSEC_PER_USEC);
1688		result += (u64)words * word_delay_us;
1689	}
1690
1691	return min(result, U32_MAX);
1692}
1693
1694static int spi_imx_transfer_one(struct spi_controller *controller,
1695				struct spi_device *spi,
1696				struct spi_transfer *transfer)
1697{
1698	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
 
1699
1700	spi_imx_setupxfer(spi, transfer);
1701	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1702
1703	/* flush rxfifo before transfer */
1704	while (spi_imx->devtype_data->rx_available(spi_imx))
1705		readl(spi_imx->base + MXC_CSPIRXDATA);
1706
1707	if (spi_imx->target_mode)
1708		return spi_imx_pio_transfer_target(spi, transfer);
1709
1710	/*
1711	 * If we decided in spi_imx_can_dma() that we want to do a DMA
1712	 * transfer, the SPI transfer has already been mapped, so we
1713	 * have to do the DMA transfer here.
1714	 */
1715	if (spi_imx->usedma)
1716		return spi_imx_dma_transfer(spi_imx, transfer);
 
 
 
 
 
 
1717
1718	/* run in polling mode for short transfers */
1719	if (transfer->len == 1 || (polling_limit_us &&
1720				   spi_imx_transfer_estimate_time_us(transfer) < polling_limit_us))
1721		return spi_imx_poll_transfer(spi, transfer);
1722
1723	return spi_imx_pio_transfer(spi, transfer);
1724}
1725
1726static int spi_imx_setup(struct spi_device *spi)
1727{
1728	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1729		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1730
1731	return 0;
1732}
1733
 
 
 
 
1734static int
1735spi_imx_prepare_message(struct spi_controller *controller, struct spi_message *msg)
1736{
1737	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1738	int ret;
1739
1740	ret = pm_runtime_resume_and_get(spi_imx->dev);
1741	if (ret < 0) {
1742		dev_err(spi_imx->dev, "failed to enable clock\n");
1743		return ret;
1744	}
1745
1746	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1747	if (ret) {
1748		pm_runtime_mark_last_busy(spi_imx->dev);
1749		pm_runtime_put_autosuspend(spi_imx->dev);
1750	}
1751
1752	return ret;
1753}
1754
1755static int
1756spi_imx_unprepare_message(struct spi_controller *controller, struct spi_message *msg)
1757{
1758	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1759
1760	pm_runtime_mark_last_busy(spi_imx->dev);
1761	pm_runtime_put_autosuspend(spi_imx->dev);
1762	return 0;
1763}
1764
1765static int spi_imx_target_abort(struct spi_controller *controller)
1766{
1767	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1768
1769	spi_imx->target_aborted = true;
1770	complete(&spi_imx->xfer_done);
1771
1772	return 0;
1773}
1774
1775static int spi_imx_probe(struct platform_device *pdev)
1776{
1777	struct device_node *np = pdev->dev.of_node;
1778	struct spi_controller *controller;
1779	struct spi_imx_data *spi_imx;
1780	struct resource *res;
1781	int ret, irq, spi_drctl;
1782	const struct spi_imx_devtype_data *devtype_data =
1783			of_device_get_match_data(&pdev->dev);
1784	bool target_mode;
1785	u32 val;
1786
1787	target_mode = devtype_data->has_targetmode &&
1788		      of_property_read_bool(np, "spi-slave");
1789	if (target_mode)
1790		controller = spi_alloc_target(&pdev->dev,
 
 
 
1791					      sizeof(struct spi_imx_data));
1792	else
1793		controller = spi_alloc_host(&pdev->dev,
1794					    sizeof(struct spi_imx_data));
1795	if (!controller)
1796		return -ENOMEM;
1797
1798	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1799	if ((ret < 0) || (spi_drctl >= 0x3)) {
1800		/* '11' is reserved */
1801		spi_drctl = 0;
1802	}
1803
1804	platform_set_drvdata(pdev, controller);
1805
1806	controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1807	controller->bus_num = np ? -1 : pdev->id;
1808	controller->use_gpio_descriptors = true;
1809
1810	spi_imx = spi_controller_get_devdata(controller);
1811	spi_imx->controller = controller;
1812	spi_imx->dev = &pdev->dev;
1813	spi_imx->target_mode = target_mode;
1814
1815	spi_imx->devtype_data = devtype_data;
1816
1817	/*
1818	 * Get number of chip selects from device properties. This can be
1819	 * coming from device tree or boardfiles, if it is not defined,
1820	 * a default value of 3 chip selects will be used, as all the legacy
1821	 * board files have <= 3 chip selects.
1822	 */
1823	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1824		controller->num_chipselect = val;
1825	else
1826		controller->num_chipselect = 3;
1827
1828	controller->transfer_one = spi_imx_transfer_one;
1829	controller->setup = spi_imx_setup;
1830	controller->prepare_message = spi_imx_prepare_message;
1831	controller->unprepare_message = spi_imx_unprepare_message;
1832	controller->target_abort = spi_imx_target_abort;
1833	controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS |
1834				SPI_MOSI_IDLE_LOW;
1835
1836	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1837	    is_imx53_ecspi(spi_imx))
1838		controller->mode_bits |= SPI_LOOP | SPI_READY;
1839
1840	if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx))
1841		controller->mode_bits |= SPI_RX_CPHA_FLIP;
1842
1843	if (is_imx51_ecspi(spi_imx) &&
1844	    device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
1845		/*
1846		 * When using HW-CS implementing SPI_CS_WORD can be done by just
1847		 * setting the burst length to the word size. This is
1848		 * considerably faster than manually controlling the CS.
1849		 */
1850		controller->mode_bits |= SPI_CS_WORD;
1851
1852	if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx)) {
1853		controller->max_native_cs = 4;
1854		controller->flags |= SPI_CONTROLLER_GPIO_SS;
1855	}
1856
1857	spi_imx->spi_drctl = spi_drctl;
1858
1859	init_completion(&spi_imx->xfer_done);
1860
1861	spi_imx->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 
1862	if (IS_ERR(spi_imx->base)) {
1863		ret = PTR_ERR(spi_imx->base);
1864		goto out_controller_put;
1865	}
1866	spi_imx->base_phys = res->start;
1867
1868	irq = platform_get_irq(pdev, 0);
1869	if (irq < 0) {
1870		ret = irq;
1871		goto out_controller_put;
1872	}
1873
1874	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1875			       dev_name(&pdev->dev), spi_imx);
1876	if (ret) {
1877		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1878		goto out_controller_put;
1879	}
1880
1881	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1882	if (IS_ERR(spi_imx->clk_ipg)) {
1883		ret = PTR_ERR(spi_imx->clk_ipg);
1884		goto out_controller_put;
1885	}
1886
1887	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1888	if (IS_ERR(spi_imx->clk_per)) {
1889		ret = PTR_ERR(spi_imx->clk_per);
1890		goto out_controller_put;
1891	}
1892
1893	ret = clk_prepare_enable(spi_imx->clk_per);
1894	if (ret)
1895		goto out_controller_put;
1896
1897	ret = clk_prepare_enable(spi_imx->clk_ipg);
1898	if (ret)
1899		goto out_put_per;
1900
1901	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1902	pm_runtime_use_autosuspend(spi_imx->dev);
1903	pm_runtime_get_noresume(spi_imx->dev);
1904	pm_runtime_set_active(spi_imx->dev);
1905	pm_runtime_enable(spi_imx->dev);
1906
1907	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1908	/*
1909	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1910	 * if validated on other chips.
1911	 */
1912	if (spi_imx->devtype_data->has_dmamode) {
1913		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, controller);
1914		if (ret == -EPROBE_DEFER)
1915			goto out_runtime_pm_put;
1916
1917		if (ret < 0)
1918			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1919				ret);
1920	}
1921
1922	spi_imx->devtype_data->reset(spi_imx);
1923
1924	spi_imx->devtype_data->intctrl(spi_imx, 0);
1925
1926	controller->dev.of_node = pdev->dev.of_node;
1927	ret = spi_register_controller(controller);
1928	if (ret) {
1929		dev_err_probe(&pdev->dev, ret, "register controller failed\n");
1930		goto out_register_controller;
1931	}
1932
1933	pm_runtime_mark_last_busy(spi_imx->dev);
1934	pm_runtime_put_autosuspend(spi_imx->dev);
1935
1936	return ret;
1937
1938out_register_controller:
1939	if (spi_imx->devtype_data->has_dmamode)
1940		spi_imx_sdma_exit(spi_imx);
1941out_runtime_pm_put:
1942	pm_runtime_dont_use_autosuspend(spi_imx->dev);
 
1943	pm_runtime_disable(spi_imx->dev);
1944	pm_runtime_set_suspended(&pdev->dev);
1945
1946	clk_disable_unprepare(spi_imx->clk_ipg);
1947out_put_per:
1948	clk_disable_unprepare(spi_imx->clk_per);
1949out_controller_put:
1950	spi_controller_put(controller);
1951
1952	return ret;
1953}
1954
1955static void spi_imx_remove(struct platform_device *pdev)
1956{
1957	struct spi_controller *controller = platform_get_drvdata(pdev);
1958	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1959	int ret;
1960
1961	spi_unregister_controller(controller);
1962
1963	ret = pm_runtime_get_sync(spi_imx->dev);
1964	if (ret >= 0)
1965		writel(0, spi_imx->base + MXC_CSPICTRL);
1966	else
1967		dev_warn(spi_imx->dev, "failed to enable clock, skip hw disable\n");
 
 
1968
1969	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1970	pm_runtime_put_sync(spi_imx->dev);
1971	pm_runtime_disable(spi_imx->dev);
1972
1973	spi_imx_sdma_exit(spi_imx);
 
 
1974}
1975
1976static int spi_imx_runtime_resume(struct device *dev)
1977{
1978	struct spi_controller *controller = dev_get_drvdata(dev);
1979	struct spi_imx_data *spi_imx;
1980	int ret;
1981
1982	spi_imx = spi_controller_get_devdata(controller);
1983
1984	ret = clk_prepare_enable(spi_imx->clk_per);
1985	if (ret)
1986		return ret;
1987
1988	ret = clk_prepare_enable(spi_imx->clk_ipg);
1989	if (ret) {
1990		clk_disable_unprepare(spi_imx->clk_per);
1991		return ret;
1992	}
1993
1994	return 0;
1995}
1996
1997static int spi_imx_runtime_suspend(struct device *dev)
1998{
1999	struct spi_controller *controller = dev_get_drvdata(dev);
2000	struct spi_imx_data *spi_imx;
2001
2002	spi_imx = spi_controller_get_devdata(controller);
2003
2004	clk_disable_unprepare(spi_imx->clk_per);
2005	clk_disable_unprepare(spi_imx->clk_ipg);
2006
2007	return 0;
2008}
2009
2010static int spi_imx_suspend(struct device *dev)
2011{
2012	pinctrl_pm_select_sleep_state(dev);
2013	return 0;
2014}
2015
2016static int spi_imx_resume(struct device *dev)
2017{
2018	pinctrl_pm_select_default_state(dev);
2019	return 0;
2020}
2021
2022static const struct dev_pm_ops imx_spi_pm = {
2023	RUNTIME_PM_OPS(spi_imx_runtime_suspend,	spi_imx_runtime_resume, NULL)
2024	SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
 
2025};
2026
2027static struct platform_driver spi_imx_driver = {
2028	.driver = {
2029		   .name = DRIVER_NAME,
2030		   .of_match_table = spi_imx_dt_ids,
2031		   .pm = pm_ptr(&imx_spi_pm),
2032	},
2033	.probe = spi_imx_probe,
2034	.remove = spi_imx_remove,
2035};
2036module_platform_driver(spi_imx_driver);
2037
2038MODULE_DESCRIPTION("i.MX SPI Controller driver");
2039MODULE_AUTHOR("Sascha Hauer, Pengutronix");
2040MODULE_LICENSE("GPL");
2041MODULE_ALIAS("platform:" DRIVER_NAME);