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v3.1
   1/*
   2 * TI OMAP I2C master mode driver
   3 *
   4 * Copyright (C) 2003 MontaVista Software, Inc.
   5 * Copyright (C) 2005 Nokia Corporation
   6 * Copyright (C) 2004 - 2007 Texas Instruments.
   7 *
   8 * Originally written by MontaVista Software, Inc.
   9 * Additional contributions by:
  10 *	Tony Lindgren <tony@atomide.com>
  11 *	Imre Deak <imre.deak@nokia.com>
  12 *	Juha Yrjölä <juha.yrjola@solidboot.com>
  13 *	Syed Khasim <x0khasim@ti.com>
  14 *	Nishant Menon <nm@ti.com>
  15 *
  16 * This program is free software; you can redistribute it and/or modify
  17 * it under the terms of the GNU General Public License as published by
  18 * the Free Software Foundation; either version 2 of the License, or
  19 * (at your option) any later version.
  20 *
  21 * This program is distributed in the hope that it will be useful,
  22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  24 * GNU General Public License for more details.
  25 *
  26 * You should have received a copy of the GNU General Public License
  27 * along with this program; if not, write to the Free Software
  28 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29 */
  30
  31#include <linux/module.h>
  32#include <linux/delay.h>
  33#include <linux/i2c.h>
  34#include <linux/err.h>
  35#include <linux/interrupt.h>
  36#include <linux/completion.h>
  37#include <linux/platform_device.h>
  38#include <linux/clk.h>
  39#include <linux/io.h>
 
 
  40#include <linux/slab.h>
  41#include <linux/i2c-omap.h>
  42#include <linux/pm_runtime.h>
  43
  44/* I2C controller revisions */
  45#define OMAP_I2C_REV_2			0x20
  46
  47/* I2C controller revisions present on specific hardware */
  48#define OMAP_I2C_REV_ON_2430		0x36
  49#define OMAP_I2C_REV_ON_3430		0x3C
  50#define OMAP_I2C_REV_ON_4430		0x40
 
  51
  52/* timeout waiting for the controller to respond */
  53#define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
  54
 
 
 
  55/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
  56enum {
  57	OMAP_I2C_REV_REG = 0,
  58	OMAP_I2C_IE_REG,
  59	OMAP_I2C_STAT_REG,
  60	OMAP_I2C_IV_REG,
  61	OMAP_I2C_WE_REG,
  62	OMAP_I2C_SYSS_REG,
  63	OMAP_I2C_BUF_REG,
  64	OMAP_I2C_CNT_REG,
  65	OMAP_I2C_DATA_REG,
  66	OMAP_I2C_SYSC_REG,
  67	OMAP_I2C_CON_REG,
  68	OMAP_I2C_OA_REG,
  69	OMAP_I2C_SA_REG,
  70	OMAP_I2C_PSC_REG,
  71	OMAP_I2C_SCLL_REG,
  72	OMAP_I2C_SCLH_REG,
  73	OMAP_I2C_SYSTEST_REG,
  74	OMAP_I2C_BUFSTAT_REG,
  75	OMAP_I2C_REVNB_LO,
  76	OMAP_I2C_REVNB_HI,
  77	OMAP_I2C_IRQSTATUS_RAW,
  78	OMAP_I2C_IRQENABLE_SET,
  79	OMAP_I2C_IRQENABLE_CLR,
 
  80};
  81
  82/* I2C Interrupt Enable Register (OMAP_I2C_IE): */
  83#define OMAP_I2C_IE_XDR		(1 << 14)	/* TX Buffer drain int enable */
  84#define OMAP_I2C_IE_RDR		(1 << 13)	/* RX Buffer drain int enable */
  85#define OMAP_I2C_IE_XRDY	(1 << 4)	/* TX data ready int enable */
  86#define OMAP_I2C_IE_RRDY	(1 << 3)	/* RX data ready int enable */
  87#define OMAP_I2C_IE_ARDY	(1 << 2)	/* Access ready int enable */
  88#define OMAP_I2C_IE_NACK	(1 << 1)	/* No ack interrupt enable */
  89#define OMAP_I2C_IE_AL		(1 << 0)	/* Arbitration lost int ena */
  90
  91/* I2C Status Register (OMAP_I2C_STAT): */
  92#define OMAP_I2C_STAT_XDR	(1 << 14)	/* TX Buffer draining */
  93#define OMAP_I2C_STAT_RDR	(1 << 13)	/* RX Buffer draining */
  94#define OMAP_I2C_STAT_BB	(1 << 12)	/* Bus busy */
  95#define OMAP_I2C_STAT_ROVR	(1 << 11)	/* Receive overrun */
  96#define OMAP_I2C_STAT_XUDF	(1 << 10)	/* Transmit underflow */
  97#define OMAP_I2C_STAT_AAS	(1 << 9)	/* Address as slave */
  98#define OMAP_I2C_STAT_AD0	(1 << 8)	/* Address zero */
  99#define OMAP_I2C_STAT_XRDY	(1 << 4)	/* Transmit data ready */
 100#define OMAP_I2C_STAT_RRDY	(1 << 3)	/* Receive data ready */
 101#define OMAP_I2C_STAT_ARDY	(1 << 2)	/* Register access ready */
 102#define OMAP_I2C_STAT_NACK	(1 << 1)	/* No ack interrupt enable */
 103#define OMAP_I2C_STAT_AL	(1 << 0)	/* Arbitration lost int ena */
 104
 105/* I2C WE wakeup enable register */
 106#define OMAP_I2C_WE_XDR_WE	(1 << 14)	/* TX drain wakup */
 107#define OMAP_I2C_WE_RDR_WE	(1 << 13)	/* RX drain wakeup */
 108#define OMAP_I2C_WE_AAS_WE	(1 << 9)	/* Address as slave wakeup*/
 109#define OMAP_I2C_WE_BF_WE	(1 << 8)	/* Bus free wakeup */
 110#define OMAP_I2C_WE_STC_WE	(1 << 6)	/* Start condition wakeup */
 111#define OMAP_I2C_WE_GC_WE	(1 << 5)	/* General call wakeup */
 112#define OMAP_I2C_WE_DRDY_WE	(1 << 3)	/* TX/RX data ready wakeup */
 113#define OMAP_I2C_WE_ARDY_WE	(1 << 2)	/* Reg access ready wakeup */
 114#define OMAP_I2C_WE_NACK_WE	(1 << 1)	/* No acknowledgment wakeup */
 115#define OMAP_I2C_WE_AL_WE	(1 << 0)	/* Arbitration lost wakeup */
 116
 117#define OMAP_I2C_WE_ALL		(OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
 118				OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
 119				OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
 120				OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
 121				OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
 122
 123/* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
 124#define OMAP_I2C_BUF_RDMA_EN	(1 << 15)	/* RX DMA channel enable */
 125#define OMAP_I2C_BUF_RXFIF_CLR	(1 << 14)	/* RX FIFO Clear */
 126#define OMAP_I2C_BUF_XDMA_EN	(1 << 7)	/* TX DMA channel enable */
 127#define OMAP_I2C_BUF_TXFIF_CLR	(1 << 6)	/* TX FIFO Clear */
 128
 129/* I2C Configuration Register (OMAP_I2C_CON): */
 130#define OMAP_I2C_CON_EN		(1 << 15)	/* I2C module enable */
 131#define OMAP_I2C_CON_BE		(1 << 14)	/* Big endian mode */
 132#define OMAP_I2C_CON_OPMODE_HS	(1 << 12)	/* High Speed support */
 133#define OMAP_I2C_CON_STB	(1 << 11)	/* Start byte mode (master) */
 134#define OMAP_I2C_CON_MST	(1 << 10)	/* Master/slave mode */
 135#define OMAP_I2C_CON_TRX	(1 << 9)	/* TX/RX mode (master only) */
 136#define OMAP_I2C_CON_XA		(1 << 8)	/* Expand address */
 137#define OMAP_I2C_CON_RM		(1 << 2)	/* Repeat mode (master only) */
 138#define OMAP_I2C_CON_STP	(1 << 1)	/* Stop cond (master only) */
 139#define OMAP_I2C_CON_STT	(1 << 0)	/* Start condition (master) */
 140
 141/* I2C SCL time value when Master */
 142#define OMAP_I2C_SCLL_HSSCLL	8
 143#define OMAP_I2C_SCLH_HSSCLH	8
 144
 145/* I2C System Test Register (OMAP_I2C_SYSTEST): */
 146#ifdef DEBUG
 147#define OMAP_I2C_SYSTEST_ST_EN		(1 << 15)	/* System test enable */
 148#define OMAP_I2C_SYSTEST_FREE		(1 << 14)	/* Free running mode */
 149#define OMAP_I2C_SYSTEST_TMODE_MASK	(3 << 12)	/* Test mode select */
 150#define OMAP_I2C_SYSTEST_TMODE_SHIFT	(12)		/* Test mode select */
 151#define OMAP_I2C_SYSTEST_SCL_I		(1 << 3)	/* SCL line sense in */
 152#define OMAP_I2C_SYSTEST_SCL_O		(1 << 2)	/* SCL line drive out */
 153#define OMAP_I2C_SYSTEST_SDA_I		(1 << 1)	/* SDA line sense in */
 154#define OMAP_I2C_SYSTEST_SDA_O		(1 << 0)	/* SDA line drive out */
 155#endif
 156
 157/* OCP_SYSSTATUS bit definitions */
 158#define SYSS_RESETDONE_MASK		(1 << 0)
 159
 160/* OCP_SYSCONFIG bit definitions */
 161#define SYSC_CLOCKACTIVITY_MASK		(0x3 << 8)
 162#define SYSC_SIDLEMODE_MASK		(0x3 << 3)
 163#define SYSC_ENAWAKEUP_MASK		(1 << 2)
 164#define SYSC_SOFTRESET_MASK		(1 << 1)
 165#define SYSC_AUTOIDLE_MASK		(1 << 0)
 166
 167#define SYSC_IDLEMODE_SMART		0x2
 168#define SYSC_CLOCKACTIVITY_FCLK		0x2
 169
 170/* Errata definitions */
 171#define I2C_OMAP_ERRATA_I207		(1 << 0)
 172#define I2C_OMAP3_1P153			(1 << 1)
 
 
 173
 174struct omap_i2c_dev {
 
 175	struct device		*dev;
 176	void __iomem		*base;		/* virtual */
 177	int			irq;
 178	int			reg_shift;      /* bit shift for I2C register addresses */
 179	struct completion	cmd_complete;
 180	struct resource		*ioarea;
 181	u32			latency;	/* maximum mpu wkup latency */
 182	void			(*set_mpu_wkup_lat)(struct device *dev,
 183						    long latency);
 184	u32			speed;		/* Speed of bus in Khz */
 
 
 185	u16			cmd_err;
 186	u8			*buf;
 187	u8			*regs;
 188	size_t			buf_len;
 189	struct i2c_adapter	adapter;
 
 190	u8			fifo_size;	/* use as flag and value
 191						 * fifo_size==0 implies no fifo
 192						 * if set, should be trsh+1
 193						 */
 194	u8			rev;
 195	unsigned		b_hw:1;		/* bad h/w fixes */
 196	unsigned		idle:1;
 197	u16			iestate;	/* Saved interrupt register */
 198	u16			pscstate;
 199	u16			scllstate;
 200	u16			sclhstate;
 201	u16			bufstate;
 202	u16			syscstate;
 203	u16			westate;
 204	u16			errata;
 205};
 206
 207static const u8 reg_map[] = {
 208	[OMAP_I2C_REV_REG] = 0x00,
 209	[OMAP_I2C_IE_REG] = 0x01,
 210	[OMAP_I2C_STAT_REG] = 0x02,
 211	[OMAP_I2C_IV_REG] = 0x03,
 212	[OMAP_I2C_WE_REG] = 0x03,
 213	[OMAP_I2C_SYSS_REG] = 0x04,
 214	[OMAP_I2C_BUF_REG] = 0x05,
 215	[OMAP_I2C_CNT_REG] = 0x06,
 216	[OMAP_I2C_DATA_REG] = 0x07,
 217	[OMAP_I2C_SYSC_REG] = 0x08,
 218	[OMAP_I2C_CON_REG] = 0x09,
 219	[OMAP_I2C_OA_REG] = 0x0a,
 220	[OMAP_I2C_SA_REG] = 0x0b,
 221	[OMAP_I2C_PSC_REG] = 0x0c,
 222	[OMAP_I2C_SCLL_REG] = 0x0d,
 223	[OMAP_I2C_SCLH_REG] = 0x0e,
 224	[OMAP_I2C_SYSTEST_REG] = 0x0f,
 225	[OMAP_I2C_BUFSTAT_REG] = 0x10,
 226};
 227
 228static const u8 omap4_reg_map[] = {
 229	[OMAP_I2C_REV_REG] = 0x04,
 230	[OMAP_I2C_IE_REG] = 0x2c,
 231	[OMAP_I2C_STAT_REG] = 0x28,
 232	[OMAP_I2C_IV_REG] = 0x34,
 233	[OMAP_I2C_WE_REG] = 0x34,
 234	[OMAP_I2C_SYSS_REG] = 0x90,
 235	[OMAP_I2C_BUF_REG] = 0x94,
 236	[OMAP_I2C_CNT_REG] = 0x98,
 237	[OMAP_I2C_DATA_REG] = 0x9c,
 238	[OMAP_I2C_SYSC_REG] = 0x20,
 239	[OMAP_I2C_CON_REG] = 0xa4,
 240	[OMAP_I2C_OA_REG] = 0xa8,
 241	[OMAP_I2C_SA_REG] = 0xac,
 242	[OMAP_I2C_PSC_REG] = 0xb0,
 243	[OMAP_I2C_SCLL_REG] = 0xb4,
 244	[OMAP_I2C_SCLH_REG] = 0xb8,
 245	[OMAP_I2C_SYSTEST_REG] = 0xbC,
 246	[OMAP_I2C_BUFSTAT_REG] = 0xc0,
 247	[OMAP_I2C_REVNB_LO] = 0x00,
 248	[OMAP_I2C_REVNB_HI] = 0x04,
 249	[OMAP_I2C_IRQSTATUS_RAW] = 0x24,
 250	[OMAP_I2C_IRQENABLE_SET] = 0x2c,
 251	[OMAP_I2C_IRQENABLE_CLR] = 0x30,
 252};
 253
 254static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
 255				      int reg, u16 val)
 256{
 257	__raw_writew(val, i2c_dev->base +
 258			(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 259}
 260
 261static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 262{
 263	return __raw_readw(i2c_dev->base +
 264				(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 265}
 266
 267static void omap_i2c_unidle(struct omap_i2c_dev *dev)
 268{
 269	struct platform_device *pdev;
 270	struct omap_i2c_bus_platform_data *pdata;
 271
 272	WARN_ON(!dev->idle);
 273
 274	pdev = to_platform_device(dev->dev);
 275	pdata = pdev->dev.platform_data;
 276
 277	pm_runtime_get_sync(&pdev->dev);
 
 278
 279	if (cpu_is_omap34xx()) {
 280		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 281		omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
 282		omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
 283		omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
 284		omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, dev->bufstate);
 285		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, dev->syscstate);
 286		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
 287		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 288	}
 289	dev->idle = 0;
 290
 291	/*
 292	 * Don't write to this register if the IE state is 0 as it can
 293	 * cause deadlock.
 294	 */
 295	if (dev->iestate)
 296		omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
 297}
 298
 299static void omap_i2c_idle(struct omap_i2c_dev *dev)
 300{
 301	struct platform_device *pdev;
 302	struct omap_i2c_bus_platform_data *pdata;
 303	u16 iv;
 304
 305	WARN_ON(dev->idle);
 306
 307	pdev = to_platform_device(dev->dev);
 308	pdata = pdev->dev.platform_data;
 309
 310	dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 311	if (dev->rev >= OMAP_I2C_REV_ON_4430)
 312		omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_CLR, 1);
 313	else
 314		omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
 315
 316	if (dev->rev < OMAP_I2C_REV_2) {
 317		iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
 318	} else {
 319		omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
 320
 321		/* Flush posted write before the dev->idle store occurs */
 322		omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 323	}
 324	dev->idle = 1;
 325
 326	pm_runtime_put_sync(&pdev->dev);
 327}
 328
 329static int omap_i2c_init(struct omap_i2c_dev *dev)
 330{
 331	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
 332	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
 333	unsigned long fclk_rate = 12000000;
 334	unsigned long timeout;
 335	unsigned long internal_clk = 0;
 336	struct clk *fclk;
 
 
 337
 338	if (dev->rev >= OMAP_I2C_REV_2) {
 339		/* Disable I2C controller before soft reset */
 340		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
 341			omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
 342				~(OMAP_I2C_CON_EN));
 343
 344		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
 345		/* For some reason we need to set the EN bit before the
 346		 * reset done bit gets set. */
 347		timeout = jiffies + OMAP_I2C_TIMEOUT;
 348		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 349		while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
 350			 SYSS_RESETDONE_MASK)) {
 351			if (time_after(jiffies, timeout)) {
 352				dev_warn(dev->dev, "timeout waiting "
 353						"for controller reset\n");
 354				return -ETIMEDOUT;
 355			}
 356			msleep(1);
 357		}
 358
 359		/* SYSC register is cleared by the reset; rewrite it */
 360		if (dev->rev == OMAP_I2C_REV_ON_2430) {
 361
 362			omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
 363					   SYSC_AUTOIDLE_MASK);
 
 364
 365		} else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
 366			dev->syscstate = SYSC_AUTOIDLE_MASK;
 367			dev->syscstate |= SYSC_ENAWAKEUP_MASK;
 368			dev->syscstate |= (SYSC_IDLEMODE_SMART <<
 369			      __ffs(SYSC_SIDLEMODE_MASK));
 370			dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
 371			      __ffs(SYSC_CLOCKACTIVITY_MASK));
 372
 373			omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
 374							dev->syscstate);
 375			/*
 376			 * Enabling all wakup sources to stop I2C freezing on
 377			 * WFI instruction.
 378			 * REVISIT: Some wkup sources might not be needed.
 379			 */
 380			dev->westate = OMAP_I2C_WE_ALL;
 381			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
 382		}
 383	}
 384	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 385
 386	if (cpu_class_is_omap1()) {
 387		/*
 388		 * The I2C functional clock is the armxor_ck, so there's
 389		 * no need to get "armxor_ck" separately.  Now, if OMAP2420
 390		 * always returns 12MHz for the functional clock, we can
 391		 * do this bit unconditionally.
 392		 */
 393		fclk = clk_get(dev->dev, "fck");
 394		fclk_rate = clk_get_rate(fclk);
 395		clk_put(fclk);
 396
 397		/* TRM for 5912 says the I2C clock must be prescaled to be
 398		 * between 7 - 12 MHz. The XOR input clock is typically
 399		 * 12, 13 or 19.2 MHz. So we should have code that produces:
 400		 *
 401		 * XOR MHz	Divider		Prescaler
 402		 * 12		1		0
 403		 * 13		2		1
 404		 * 19.2		2		1
 405		 */
 406		if (fclk_rate > 12000000)
 407			psc = fclk_rate / 12000000;
 408	}
 409
 410	if (!(cpu_class_is_omap1() || cpu_is_omap2420())) {
 411
 412		/*
 413		 * HSI2C controller internal clk rate should be 19.2 Mhz for
 414		 * HS and for all modes on 2430. On 34xx we can use lower rate
 415		 * to get longer filter period for better noise suppression.
 416		 * The filter is iclk (fclk for HS) period.
 417		 */
 418		if (dev->speed > 400 || cpu_is_omap2430())
 
 419			internal_clk = 19200;
 420		else if (dev->speed > 100)
 421			internal_clk = 9600;
 422		else
 423			internal_clk = 4000;
 424		fclk = clk_get(dev->dev, "fck");
 425		fclk_rate = clk_get_rate(fclk) / 1000;
 426		clk_put(fclk);
 427
 428		/* Compute prescaler divisor */
 429		psc = fclk_rate / internal_clk;
 430		psc = psc - 1;
 431
 432		/* If configured for High Speed */
 433		if (dev->speed > 400) {
 434			unsigned long scl;
 435
 436			/* For first phase of HS mode */
 437			scl = internal_clk / 400;
 438			fsscll = scl - (scl / 3) - 7;
 439			fssclh = (scl / 3) - 5;
 440
 441			/* For second phase of HS mode */
 442			scl = fclk_rate / dev->speed;
 443			hsscll = scl - (scl / 3) - 7;
 444			hssclh = (scl / 3) - 5;
 445		} else if (dev->speed > 100) {
 446			unsigned long scl;
 447
 448			/* Fast mode */
 449			scl = internal_clk / dev->speed;
 450			fsscll = scl - (scl / 3) - 7;
 451			fssclh = (scl / 3) - 5;
 452		} else {
 453			/* Standard mode */
 454			fsscll = internal_clk / (dev->speed * 2) - 7;
 455			fssclh = internal_clk / (dev->speed * 2) - 5;
 456		}
 457		scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
 458		sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
 459	} else {
 460		/* Program desired operating rate */
 461		fclk_rate /= (psc + 1) * 1000;
 462		if (psc > 2)
 463			psc = 2;
 464		scll = fclk_rate / (dev->speed * 2) - 7 + psc;
 465		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
 466	}
 467
 468	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
 469	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
 470
 471	/* SCL low and high time values */
 472	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
 473	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
 474
 475	if (dev->fifo_size) {
 476		/* Note: setup required fifo size - 1. RTRSH and XTRSH */
 477		buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
 478			(dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
 479		omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
 480	}
 481
 482	/* Take the I2C module out of reset: */
 483	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 484
 485	dev->errata = 0;
 486
 487	if (cpu_is_omap2430() || cpu_is_omap34xx())
 488		dev->errata |= I2C_OMAP_ERRATA_I207;
 489
 490	/* Enable interrupts */
 491	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 492			OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
 493			OMAP_I2C_IE_AL)  | ((dev->fifo_size) ?
 494				(OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
 495	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
 496	if (cpu_is_omap34xx()) {
 497		dev->pscstate = psc;
 498		dev->scllstate = scll;
 499		dev->sclhstate = sclh;
 500		dev->bufstate = buf;
 501	}
 502	return 0;
 503}
 504
 505/*
 506 * Waiting on Bus Busy
 507 */
 508static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
 509{
 510	unsigned long timeout;
 511
 512	timeout = jiffies + OMAP_I2C_TIMEOUT;
 513	while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
 514		if (time_after(jiffies, timeout)) {
 515			dev_warn(dev->dev, "timeout waiting for bus ready\n");
 516			return -ETIMEDOUT;
 517		}
 518		msleep(1);
 519	}
 520
 521	return 0;
 522}
 523
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 524/*
 525 * Low level master read/write transaction.
 526 */
 527static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 528			     struct i2c_msg *msg, int stop)
 529{
 530	struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 531	int r;
 532	u16 w;
 533
 534	dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
 535		msg->addr, msg->len, msg->flags, stop);
 536
 537	if (msg->len == 0)
 538		return -EINVAL;
 539
 
 
 
 540	omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
 541
 542	/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
 543	dev->buf = msg->buf;
 544	dev->buf_len = msg->len;
 545
 
 
 
 546	omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
 547
 548	/* Clear the FIFO Buffers */
 549	w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
 550	w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
 551	omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
 552
 553	init_completion(&dev->cmd_complete);
 554	dev->cmd_err = 0;
 555
 556	w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 557
 558	/* High speed configuration */
 559	if (dev->speed > 400)
 560		w |= OMAP_I2C_CON_OPMODE_HS;
 561
 
 
 562	if (msg->flags & I2C_M_TEN)
 563		w |= OMAP_I2C_CON_XA;
 564	if (!(msg->flags & I2C_M_RD))
 565		w |= OMAP_I2C_CON_TRX;
 566
 567	if (!dev->b_hw && stop)
 568		w |= OMAP_I2C_CON_STP;
 569
 570	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 571
 572	/*
 573	 * Don't write stt and stp together on some hardware.
 574	 */
 575	if (dev->b_hw && stop) {
 576		unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
 577		u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 578		while (con & OMAP_I2C_CON_STT) {
 579			con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 580
 581			/* Let the user know if i2c is in a bad state */
 582			if (time_after(jiffies, delay)) {
 583				dev_err(dev->dev, "controller timed out "
 584				"waiting for start condition to finish\n");
 585				return -ETIMEDOUT;
 586			}
 587			cpu_relax();
 588		}
 589
 590		w |= OMAP_I2C_CON_STP;
 591		w &= ~OMAP_I2C_CON_STT;
 592		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 593	}
 594
 595	/*
 596	 * REVISIT: We should abort the transfer on signals, but the bus goes
 597	 * into arbitration and we're currently unable to recover from it.
 598	 */
 599	r = wait_for_completion_timeout(&dev->cmd_complete,
 600					OMAP_I2C_TIMEOUT);
 601	dev->buf_len = 0;
 602	if (r < 0)
 603		return r;
 604	if (r == 0) {
 605		dev_err(dev->dev, "controller timed out\n");
 606		omap_i2c_init(dev);
 
 607		return -ETIMEDOUT;
 608	}
 609
 610	if (likely(!dev->cmd_err))
 611		return 0;
 612
 613	/* We have an error */
 614	if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
 615			    OMAP_I2C_STAT_XUDF)) {
 616		omap_i2c_init(dev);
 
 617		return -EIO;
 618	}
 619
 620	if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
 621		if (msg->flags & I2C_M_IGNORE_NAK)
 622			return 0;
 623		if (stop) {
 624			w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 625			w |= OMAP_I2C_CON_STP;
 626			omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 627		}
 628		return -EREMOTEIO;
 629	}
 630	return -EIO;
 631}
 632
 633
 634/*
 635 * Prepare controller for a transaction and call omap_i2c_xfer_msg
 636 * to do the work during IRQ processing.
 637 */
 638static int
 639omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 640{
 641	struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 642	int i;
 643	int r;
 644
 645	omap_i2c_unidle(dev);
 
 
 646
 647	r = omap_i2c_wait_for_bb(dev);
 648	if (r < 0)
 649		goto out;
 650
 651	if (dev->set_mpu_wkup_lat != NULL)
 652		dev->set_mpu_wkup_lat(dev->dev, dev->latency);
 653
 654	for (i = 0; i < num; i++) {
 655		r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
 656		if (r != 0)
 657			break;
 658	}
 659
 660	if (dev->set_mpu_wkup_lat != NULL)
 661		dev->set_mpu_wkup_lat(dev->dev, -1);
 662
 663	if (r == 0)
 664		r = num;
 665
 666	omap_i2c_wait_for_bb(dev);
 
 
 
 
 667out:
 668	omap_i2c_idle(dev);
 
 669	return r;
 670}
 671
 672static u32
 673omap_i2c_func(struct i2c_adapter *adap)
 674{
 675	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
 
 676}
 677
 678static inline void
 679omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
 680{
 681	dev->cmd_err |= err;
 682	complete(&dev->cmd_complete);
 683}
 684
 685static inline void
 686omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
 687{
 688	omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
 689}
 690
 691static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
 692{
 693	/*
 694	 * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
 695	 * Not applicable for OMAP4.
 696	 * Under certain rare conditions, RDR could be set again
 697	 * when the bus is busy, then ignore the interrupt and
 698	 * clear the interrupt.
 699	 */
 700	if (stat & OMAP_I2C_STAT_RDR) {
 701		/* Step 1: If RDR is set, clear it */
 702		omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 703
 704		/* Step 2: */
 705		if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 706						& OMAP_I2C_STAT_BB)) {
 707
 708			/* Step 3: */
 709			if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 710						& OMAP_I2C_STAT_RDR) {
 711				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 712				dev_dbg(dev->dev, "RDR when bus is busy.\n");
 713			}
 714
 715		}
 716	}
 717}
 718
 719/* rev1 devices are apparently only on some 15xx */
 720#ifdef CONFIG_ARCH_OMAP15XX
 721
 722static irqreturn_t
 723omap_i2c_rev1_isr(int this_irq, void *dev_id)
 724{
 725	struct omap_i2c_dev *dev = dev_id;
 726	u16 iv, w;
 727
 728	if (dev->idle)
 729		return IRQ_NONE;
 730
 731	iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
 732	switch (iv) {
 733	case 0x00:	/* None */
 734		break;
 735	case 0x01:	/* Arbitration lost */
 736		dev_err(dev->dev, "Arbitration lost\n");
 737		omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
 738		break;
 739	case 0x02:	/* No acknowledgement */
 740		omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
 741		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
 742		break;
 743	case 0x03:	/* Register access ready */
 744		omap_i2c_complete_cmd(dev, 0);
 745		break;
 746	case 0x04:	/* Receive data ready */
 747		if (dev->buf_len) {
 748			w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 749			*dev->buf++ = w;
 750			dev->buf_len--;
 751			if (dev->buf_len) {
 752				*dev->buf++ = w >> 8;
 753				dev->buf_len--;
 754			}
 755		} else
 756			dev_err(dev->dev, "RRDY IRQ while no data requested\n");
 757		break;
 758	case 0x05:	/* Transmit data ready */
 759		if (dev->buf_len) {
 760			w = *dev->buf++;
 761			dev->buf_len--;
 762			if (dev->buf_len) {
 763				w |= *dev->buf++ << 8;
 764				dev->buf_len--;
 765			}
 766			omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 767		} else
 768			dev_err(dev->dev, "XRDY IRQ while no data to send\n");
 769		break;
 770	default:
 771		return IRQ_NONE;
 772	}
 773
 774	return IRQ_HANDLED;
 775}
 776#else
 777#define omap_i2c_rev1_isr		NULL
 778#endif
 779
 780/*
 781 * OMAP3430 Errata 1.153: When an XRDY/XDR is hit, wait for XUDF before writing
 782 * data to DATA_REG. Otherwise some data bytes can be lost while transferring
 783 * them from the memory to the I2C interface.
 784 */
 785static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
 786{
 787	unsigned long timeout = 10000;
 
 788
 789	while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
 790		if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 791			omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
 
 
 
 
 792							OMAP_I2C_STAT_XDR));
 793			*err |= OMAP_I2C_STAT_XUDF;
 794			return -ETIMEDOUT;
 
 
 
 
 
 
 
 
 
 
 795		}
 796
 797		cpu_relax();
 798		*stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 799	}
 800
 801	if (!timeout) {
 802		dev_err(dev->dev, "timeout waiting on XUDF bit\n");
 803		return 0;
 804	}
 805
 806	return 0;
 807}
 808
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 809static irqreturn_t
 810omap_i2c_isr(int this_irq, void *dev_id)
 811{
 812	struct omap_i2c_dev *dev = dev_id;
 
 813	u16 bits;
 814	u16 stat, w;
 815	int err, count = 0;
 816
 817	if (dev->idle)
 818		return IRQ_NONE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 819
 820	bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 821	while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
 822		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 823		if (count++ == 100) {
 824			dev_warn(dev->dev, "Too much work in one IRQ\n");
 825			break;
 826		}
 827
 828		err = 0;
 829complete:
 830		/*
 831		 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
 832		 * acked after the data operation is complete.
 833		 * Ref: TRM SWPU114Q Figure 18-31
 834		 */
 835		omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
 836				~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
 837				OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
 838
 839		if (stat & OMAP_I2C_STAT_NACK) {
 840			err |= OMAP_I2C_STAT_NACK;
 841			omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
 842					   OMAP_I2C_CON_STP);
 843		}
 
 844		if (stat & OMAP_I2C_STAT_AL) {
 845			dev_err(dev->dev, "Arbitration lost\n");
 846			err |= OMAP_I2C_STAT_AL;
 
 
 847		}
 
 848		/*
 849		 * ProDB0017052: Clear ARDY bit twice
 850		 */
 
 
 
 851		if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
 852					OMAP_I2C_STAT_AL)) {
 853			omap_i2c_ack_stat(dev, stat &
 854				(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
 855				OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR |
 856				OMAP_I2C_STAT_ARDY));
 857			omap_i2c_complete_cmd(dev, err);
 858			return IRQ_HANDLED;
 859		}
 860		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
 
 861			u8 num_bytes = 1;
 862
 
 
 
 
 
 863			if (dev->errata & I2C_OMAP_ERRATA_I207)
 864				i2c_omap_errata_i207(dev, stat);
 865
 866			if (dev->fifo_size) {
 867				if (stat & OMAP_I2C_STAT_RRDY)
 868					num_bytes = dev->fifo_size;
 869				else    /* read RXSTAT on RDR interrupt */
 870					num_bytes = (omap_i2c_read_reg(dev,
 871							OMAP_I2C_BUFSTAT_REG)
 872							>> 8) & 0x3F;
 873			}
 874			while (num_bytes) {
 875				num_bytes--;
 876				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 877				if (dev->buf_len) {
 878					*dev->buf++ = w;
 879					dev->buf_len--;
 880					/*
 881					 * Data reg in 2430, omap3 and
 882					 * omap4 is 8 bit wide
 883					 */
 884					if (cpu_class_is_omap1() ||
 885							cpu_is_omap2420()) {
 886						if (dev->buf_len) {
 887							*dev->buf++ = w >> 8;
 888							dev->buf_len--;
 889						}
 890					}
 891				} else {
 892					if (stat & OMAP_I2C_STAT_RRDY)
 893						dev_err(dev->dev,
 894							"RRDY IRQ while no data"
 895								" requested\n");
 896					if (stat & OMAP_I2C_STAT_RDR)
 897						dev_err(dev->dev,
 898							"RDR IRQ while no data"
 899								" requested\n");
 900					break;
 901				}
 902			}
 903			omap_i2c_ack_stat(dev,
 904				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
 905			continue;
 906		}
 907		if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
 
 908			u8 num_bytes = 1;
 909			if (dev->fifo_size) {
 910				if (stat & OMAP_I2C_STAT_XRDY)
 911					num_bytes = dev->fifo_size;
 912				else    /* read TXSTAT on XDR interrupt */
 913					num_bytes = omap_i2c_read_reg(dev,
 914							OMAP_I2C_BUFSTAT_REG)
 915							& 0x3F;
 916			}
 917			while (num_bytes) {
 918				num_bytes--;
 919				w = 0;
 920				if (dev->buf_len) {
 921					w = *dev->buf++;
 922					dev->buf_len--;
 923					/*
 924					 * Data reg in 2430, omap3 and
 925					 * omap4 is 8 bit wide
 926					 */
 927					if (cpu_class_is_omap1() ||
 928							cpu_is_omap2420()) {
 929						if (dev->buf_len) {
 930							w |= *dev->buf++ << 8;
 931							dev->buf_len--;
 932						}
 933					}
 934				} else {
 935					if (stat & OMAP_I2C_STAT_XRDY)
 936						dev_err(dev->dev,
 937							"XRDY IRQ while no "
 938							"data to send\n");
 939					if (stat & OMAP_I2C_STAT_XDR)
 940						dev_err(dev->dev,
 941							"XDR IRQ while no "
 942							"data to send\n");
 943					break;
 944				}
 945
 946				if ((dev->errata & I2C_OMAP3_1P153) &&
 947				    errata_omap3_1p153(dev, &stat, &err))
 948					goto complete;
 949
 950				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 951			}
 952			omap_i2c_ack_stat(dev,
 953				stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 954			continue;
 955		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 956		if (stat & OMAP_I2C_STAT_ROVR) {
 957			dev_err(dev->dev, "Receive overrun\n");
 958			dev->cmd_err |= OMAP_I2C_STAT_ROVR;
 
 
 959		}
 
 960		if (stat & OMAP_I2C_STAT_XUDF) {
 961			dev_err(dev->dev, "Transmit underflow\n");
 962			dev->cmd_err |= OMAP_I2C_STAT_XUDF;
 
 
 963		}
 964	}
 965
 966	return count ? IRQ_HANDLED : IRQ_NONE;
 
 
 
 
 
 967}
 968
 969static const struct i2c_algorithm omap_i2c_algo = {
 970	.master_xfer	= omap_i2c_xfer,
 971	.functionality	= omap_i2c_func,
 972};
 973
 974static int __devinit
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 975omap_i2c_probe(struct platform_device *pdev)
 976{
 977	struct omap_i2c_dev	*dev;
 978	struct i2c_adapter	*adap;
 979	struct resource		*mem, *irq, *ioarea;
 980	struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
 981	irq_handler_t isr;
 
 
 
 982	int r;
 983	u32 speed = 0;
 
 984
 985	/* NOTE: driver uses the static register mapping */
 986	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 987	if (!mem) {
 988		dev_err(&pdev->dev, "no mem resource?\n");
 989		return -ENODEV;
 990	}
 991	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 992	if (!irq) {
 993		dev_err(&pdev->dev, "no irq resource?\n");
 994		return -ENODEV;
 995	}
 996
 997	ioarea = request_mem_region(mem->start, resource_size(mem),
 998			pdev->name);
 999	if (!ioarea) {
1000		dev_err(&pdev->dev, "I2C region already claimed\n");
1001		return -EBUSY;
1002	}
1003
1004	dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
1005	if (!dev) {
1006		r = -ENOMEM;
1007		goto err_release_region;
1008	}
1009
1010	if (pdata != NULL) {
1011		speed = pdata->clkrate;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1012		dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
1013	} else {
1014		speed = 100;	/* Default speed */
1015		dev->set_mpu_wkup_lat = NULL;
1016	}
1017
1018	dev->speed = speed;
1019	dev->idle = 1;
1020	dev->dev = &pdev->dev;
1021	dev->irq = irq->start;
1022	dev->base = ioremap(mem->start, resource_size(mem));
1023	if (!dev->base) {
1024		r = -ENOMEM;
1025		goto err_free_mem;
1026	}
1027
1028	platform_set_drvdata(pdev, dev);
 
1029
1030	if (cpu_is_omap7xx())
1031		dev->reg_shift = 1;
1032	else if (cpu_is_omap44xx())
1033		dev->reg_shift = 0;
1034	else
1035		dev->reg_shift = 2;
1036
1037	if (cpu_is_omap44xx())
1038		dev->regs = (u8 *) omap4_reg_map;
1039	else
1040		dev->regs = (u8 *) reg_map;
1041
1042	pm_runtime_enable(&pdev->dev);
1043	omap_i2c_unidle(dev);
 
1044
1045	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1046
1047	if (dev->rev <= OMAP_I2C_REV_ON_3430)
1048		dev->errata |= I2C_OMAP3_1P153;
1049
1050	if (!(cpu_class_is_omap1() || cpu_is_omap2420())) {
1051		u16 s;
1052
1053		/* Set up the fifo size - Get total size */
1054		s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1055		dev->fifo_size = 0x8 << s;
1056
1057		/*
1058		 * Set up notification threshold as half the total available
1059		 * size. This is to ensure that we can handle the status on int
1060		 * call back latencies.
1061		 */
1062		if (dev->rev >= OMAP_I2C_REV_ON_4430) {
1063			dev->fifo_size = 0;
1064			dev->b_hw = 0; /* Disable hardware fixes */
1065		} else {
1066			dev->fifo_size = (dev->fifo_size / 2);
1067			dev->b_hw = 1; /* Enable hardware fixes */
1068		}
1069		/* calculate wakeup latency constraint for MPU */
1070		if (dev->set_mpu_wkup_lat != NULL)
1071			dev->latency = (1000000 * dev->fifo_size) /
1072				       (1000 * speed / 8);
1073	}
1074
1075	/* reset ASAP, clearing any IRQs */
1076	omap_i2c_init(dev);
1077
1078	isr = (dev->rev < OMAP_I2C_REV_2) ? omap_i2c_rev1_isr : omap_i2c_isr;
1079	r = request_irq(dev->irq, isr, 0, pdev->name, dev);
 
 
 
 
 
 
1080
1081	if (r) {
1082		dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1083		goto err_unuse_clocks;
1084	}
1085
1086	dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n",
1087		 pdev->id, dev->rev >> 4, dev->rev & 0xf, dev->speed);
1088
1089	omap_i2c_idle(dev);
1090
1091	adap = &dev->adapter;
1092	i2c_set_adapdata(adap, dev);
1093	adap->owner = THIS_MODULE;
1094	adap->class = I2C_CLASS_HWMON;
1095	strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
1096	adap->algo = &omap_i2c_algo;
1097	adap->dev.parent = &pdev->dev;
 
1098
1099	/* i2c device drivers may be active on return from add_adapter() */
1100	adap->nr = pdev->id;
1101	r = i2c_add_numbered_adapter(adap);
1102	if (r) {
1103		dev_err(dev->dev, "failure adding adapter\n");
1104		goto err_free_irq;
1105	}
1106
 
 
 
 
 
 
1107	return 0;
1108
1109err_free_irq:
1110	free_irq(dev->irq, dev);
1111err_unuse_clocks:
1112	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1113	omap_i2c_idle(dev);
1114	iounmap(dev->base);
1115err_free_mem:
1116	platform_set_drvdata(pdev, NULL);
1117	kfree(dev);
1118err_release_region:
1119	release_mem_region(mem->start, resource_size(mem));
1120
1121	return r;
1122}
1123
1124static int
1125omap_i2c_remove(struct platform_device *pdev)
1126{
1127	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
1128	struct resource		*mem;
1129
1130	platform_set_drvdata(pdev, NULL);
1131
1132	free_irq(dev->irq, dev);
1133	i2c_del_adapter(&dev->adapter);
 
 
 
 
1134	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1135	iounmap(dev->base);
1136	kfree(dev);
1137	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1138	release_mem_region(mem->start, resource_size(mem));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1139	return 0;
1140}
 
 
 
 
 
 
 
 
 
 
1141
1142static struct platform_driver omap_i2c_driver = {
1143	.probe		= omap_i2c_probe,
1144	.remove		= omap_i2c_remove,
1145	.driver		= {
1146		.name	= "omap_i2c",
1147		.owner	= THIS_MODULE,
 
 
1148	},
1149};
1150
1151/* I2C may be needed to bring up other drivers */
1152static int __init
1153omap_i2c_init_driver(void)
1154{
1155	return platform_driver_register(&omap_i2c_driver);
1156}
1157subsys_initcall(omap_i2c_init_driver);
1158
1159static void __exit omap_i2c_exit_driver(void)
1160{
1161	platform_driver_unregister(&omap_i2c_driver);
1162}
1163module_exit(omap_i2c_exit_driver);
1164
1165MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1166MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1167MODULE_LICENSE("GPL");
1168MODULE_ALIAS("platform:omap_i2c");
v3.15
   1/*
   2 * TI OMAP I2C master mode driver
   3 *
   4 * Copyright (C) 2003 MontaVista Software, Inc.
   5 * Copyright (C) 2005 Nokia Corporation
   6 * Copyright (C) 2004 - 2007 Texas Instruments.
   7 *
   8 * Originally written by MontaVista Software, Inc.
   9 * Additional contributions by:
  10 *	Tony Lindgren <tony@atomide.com>
  11 *	Imre Deak <imre.deak@nokia.com>
  12 *	Juha Yrjölä <juha.yrjola@solidboot.com>
  13 *	Syed Khasim <x0khasim@ti.com>
  14 *	Nishant Menon <nm@ti.com>
  15 *
  16 * This program is free software; you can redistribute it and/or modify
  17 * it under the terms of the GNU General Public License as published by
  18 * the Free Software Foundation; either version 2 of the License, or
  19 * (at your option) any later version.
  20 *
  21 * This program is distributed in the hope that it will be useful,
  22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  24 * GNU General Public License for more details.
  25 *
  26 * You should have received a copy of the GNU General Public License
  27 * along with this program; if not, write to the Free Software
  28 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29 */
  30
  31#include <linux/module.h>
  32#include <linux/delay.h>
  33#include <linux/i2c.h>
  34#include <linux/err.h>
  35#include <linux/interrupt.h>
  36#include <linux/completion.h>
  37#include <linux/platform_device.h>
  38#include <linux/clk.h>
  39#include <linux/io.h>
  40#include <linux/of.h>
  41#include <linux/of_device.h>
  42#include <linux/slab.h>
  43#include <linux/i2c-omap.h>
  44#include <linux/pm_runtime.h>
  45
  46/* I2C controller revisions */
  47#define OMAP_I2C_OMAP1_REV_2		0x20
  48
  49/* I2C controller revisions present on specific hardware */
  50#define OMAP_I2C_REV_ON_2430		0x00000036
  51#define OMAP_I2C_REV_ON_3430_3530	0x0000003C
  52#define OMAP_I2C_REV_ON_3630		0x00000040
  53#define OMAP_I2C_REV_ON_4430_PLUS	0x50400002
  54
  55/* timeout waiting for the controller to respond */
  56#define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
  57
  58/* timeout for pm runtime autosuspend */
  59#define OMAP_I2C_PM_TIMEOUT		1000	/* ms */
  60
  61/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
  62enum {
  63	OMAP_I2C_REV_REG = 0,
  64	OMAP_I2C_IE_REG,
  65	OMAP_I2C_STAT_REG,
  66	OMAP_I2C_IV_REG,
  67	OMAP_I2C_WE_REG,
  68	OMAP_I2C_SYSS_REG,
  69	OMAP_I2C_BUF_REG,
  70	OMAP_I2C_CNT_REG,
  71	OMAP_I2C_DATA_REG,
  72	OMAP_I2C_SYSC_REG,
  73	OMAP_I2C_CON_REG,
  74	OMAP_I2C_OA_REG,
  75	OMAP_I2C_SA_REG,
  76	OMAP_I2C_PSC_REG,
  77	OMAP_I2C_SCLL_REG,
  78	OMAP_I2C_SCLH_REG,
  79	OMAP_I2C_SYSTEST_REG,
  80	OMAP_I2C_BUFSTAT_REG,
  81	/* only on OMAP4430 */
  82	OMAP_I2C_IP_V2_REVNB_LO,
  83	OMAP_I2C_IP_V2_REVNB_HI,
  84	OMAP_I2C_IP_V2_IRQSTATUS_RAW,
  85	OMAP_I2C_IP_V2_IRQENABLE_SET,
  86	OMAP_I2C_IP_V2_IRQENABLE_CLR,
  87};
  88
  89/* I2C Interrupt Enable Register (OMAP_I2C_IE): */
  90#define OMAP_I2C_IE_XDR		(1 << 14)	/* TX Buffer drain int enable */
  91#define OMAP_I2C_IE_RDR		(1 << 13)	/* RX Buffer drain int enable */
  92#define OMAP_I2C_IE_XRDY	(1 << 4)	/* TX data ready int enable */
  93#define OMAP_I2C_IE_RRDY	(1 << 3)	/* RX data ready int enable */
  94#define OMAP_I2C_IE_ARDY	(1 << 2)	/* Access ready int enable */
  95#define OMAP_I2C_IE_NACK	(1 << 1)	/* No ack interrupt enable */
  96#define OMAP_I2C_IE_AL		(1 << 0)	/* Arbitration lost int ena */
  97
  98/* I2C Status Register (OMAP_I2C_STAT): */
  99#define OMAP_I2C_STAT_XDR	(1 << 14)	/* TX Buffer draining */
 100#define OMAP_I2C_STAT_RDR	(1 << 13)	/* RX Buffer draining */
 101#define OMAP_I2C_STAT_BB	(1 << 12)	/* Bus busy */
 102#define OMAP_I2C_STAT_ROVR	(1 << 11)	/* Receive overrun */
 103#define OMAP_I2C_STAT_XUDF	(1 << 10)	/* Transmit underflow */
 104#define OMAP_I2C_STAT_AAS	(1 << 9)	/* Address as slave */
 105#define OMAP_I2C_STAT_AD0	(1 << 8)	/* Address zero */
 106#define OMAP_I2C_STAT_XRDY	(1 << 4)	/* Transmit data ready */
 107#define OMAP_I2C_STAT_RRDY	(1 << 3)	/* Receive data ready */
 108#define OMAP_I2C_STAT_ARDY	(1 << 2)	/* Register access ready */
 109#define OMAP_I2C_STAT_NACK	(1 << 1)	/* No ack interrupt enable */
 110#define OMAP_I2C_STAT_AL	(1 << 0)	/* Arbitration lost int ena */
 111
 112/* I2C WE wakeup enable register */
 113#define OMAP_I2C_WE_XDR_WE	(1 << 14)	/* TX drain wakup */
 114#define OMAP_I2C_WE_RDR_WE	(1 << 13)	/* RX drain wakeup */
 115#define OMAP_I2C_WE_AAS_WE	(1 << 9)	/* Address as slave wakeup*/
 116#define OMAP_I2C_WE_BF_WE	(1 << 8)	/* Bus free wakeup */
 117#define OMAP_I2C_WE_STC_WE	(1 << 6)	/* Start condition wakeup */
 118#define OMAP_I2C_WE_GC_WE	(1 << 5)	/* General call wakeup */
 119#define OMAP_I2C_WE_DRDY_WE	(1 << 3)	/* TX/RX data ready wakeup */
 120#define OMAP_I2C_WE_ARDY_WE	(1 << 2)	/* Reg access ready wakeup */
 121#define OMAP_I2C_WE_NACK_WE	(1 << 1)	/* No acknowledgment wakeup */
 122#define OMAP_I2C_WE_AL_WE	(1 << 0)	/* Arbitration lost wakeup */
 123
 124#define OMAP_I2C_WE_ALL		(OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
 125				OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
 126				OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
 127				OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
 128				OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
 129
 130/* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
 131#define OMAP_I2C_BUF_RDMA_EN	(1 << 15)	/* RX DMA channel enable */
 132#define OMAP_I2C_BUF_RXFIF_CLR	(1 << 14)	/* RX FIFO Clear */
 133#define OMAP_I2C_BUF_XDMA_EN	(1 << 7)	/* TX DMA channel enable */
 134#define OMAP_I2C_BUF_TXFIF_CLR	(1 << 6)	/* TX FIFO Clear */
 135
 136/* I2C Configuration Register (OMAP_I2C_CON): */
 137#define OMAP_I2C_CON_EN		(1 << 15)	/* I2C module enable */
 138#define OMAP_I2C_CON_BE		(1 << 14)	/* Big endian mode */
 139#define OMAP_I2C_CON_OPMODE_HS	(1 << 12)	/* High Speed support */
 140#define OMAP_I2C_CON_STB	(1 << 11)	/* Start byte mode (master) */
 141#define OMAP_I2C_CON_MST	(1 << 10)	/* Master/slave mode */
 142#define OMAP_I2C_CON_TRX	(1 << 9)	/* TX/RX mode (master only) */
 143#define OMAP_I2C_CON_XA		(1 << 8)	/* Expand address */
 144#define OMAP_I2C_CON_RM		(1 << 2)	/* Repeat mode (master only) */
 145#define OMAP_I2C_CON_STP	(1 << 1)	/* Stop cond (master only) */
 146#define OMAP_I2C_CON_STT	(1 << 0)	/* Start condition (master) */
 147
 148/* I2C SCL time value when Master */
 149#define OMAP_I2C_SCLL_HSSCLL	8
 150#define OMAP_I2C_SCLH_HSSCLH	8
 151
 152/* I2C System Test Register (OMAP_I2C_SYSTEST): */
 153#ifdef DEBUG
 154#define OMAP_I2C_SYSTEST_ST_EN		(1 << 15)	/* System test enable */
 155#define OMAP_I2C_SYSTEST_FREE		(1 << 14)	/* Free running mode */
 156#define OMAP_I2C_SYSTEST_TMODE_MASK	(3 << 12)	/* Test mode select */
 157#define OMAP_I2C_SYSTEST_TMODE_SHIFT	(12)		/* Test mode select */
 158#define OMAP_I2C_SYSTEST_SCL_I		(1 << 3)	/* SCL line sense in */
 159#define OMAP_I2C_SYSTEST_SCL_O		(1 << 2)	/* SCL line drive out */
 160#define OMAP_I2C_SYSTEST_SDA_I		(1 << 1)	/* SDA line sense in */
 161#define OMAP_I2C_SYSTEST_SDA_O		(1 << 0)	/* SDA line drive out */
 162#endif
 163
 164/* OCP_SYSSTATUS bit definitions */
 165#define SYSS_RESETDONE_MASK		(1 << 0)
 166
 167/* OCP_SYSCONFIG bit definitions */
 168#define SYSC_CLOCKACTIVITY_MASK		(0x3 << 8)
 169#define SYSC_SIDLEMODE_MASK		(0x3 << 3)
 170#define SYSC_ENAWAKEUP_MASK		(1 << 2)
 171#define SYSC_SOFTRESET_MASK		(1 << 1)
 172#define SYSC_AUTOIDLE_MASK		(1 << 0)
 173
 174#define SYSC_IDLEMODE_SMART		0x2
 175#define SYSC_CLOCKACTIVITY_FCLK		0x2
 176
 177/* Errata definitions */
 178#define I2C_OMAP_ERRATA_I207		(1 << 0)
 179#define I2C_OMAP_ERRATA_I462		(1 << 1)
 180
 181#define OMAP_I2C_IP_V2_INTERRUPTS_MASK	0x6FFF
 182
 183struct omap_i2c_dev {
 184	spinlock_t		lock;		/* IRQ synchronization */
 185	struct device		*dev;
 186	void __iomem		*base;		/* virtual */
 187	int			irq;
 188	int			reg_shift;      /* bit shift for I2C register addresses */
 189	struct completion	cmd_complete;
 190	struct resource		*ioarea;
 191	u32			latency;	/* maximum mpu wkup latency */
 192	void			(*set_mpu_wkup_lat)(struct device *dev,
 193						    long latency);
 194	u32			speed;		/* Speed of bus in kHz */
 195	u32			flags;
 196	u16			scheme;
 197	u16			cmd_err;
 198	u8			*buf;
 199	u8			*regs;
 200	size_t			buf_len;
 201	struct i2c_adapter	adapter;
 202	u8			threshold;
 203	u8			fifo_size;	/* use as flag and value
 204						 * fifo_size==0 implies no fifo
 205						 * if set, should be trsh+1
 206						 */
 207	u32			rev;
 208	unsigned		b_hw:1;		/* bad h/w fixes */
 209	unsigned		receiver:1;	/* true when we're in receiver mode */
 210	u16			iestate;	/* Saved interrupt register */
 211	u16			pscstate;
 212	u16			scllstate;
 213	u16			sclhstate;
 
 214	u16			syscstate;
 215	u16			westate;
 216	u16			errata;
 217};
 218
 219static const u8 reg_map_ip_v1[] = {
 220	[OMAP_I2C_REV_REG] = 0x00,
 221	[OMAP_I2C_IE_REG] = 0x01,
 222	[OMAP_I2C_STAT_REG] = 0x02,
 223	[OMAP_I2C_IV_REG] = 0x03,
 224	[OMAP_I2C_WE_REG] = 0x03,
 225	[OMAP_I2C_SYSS_REG] = 0x04,
 226	[OMAP_I2C_BUF_REG] = 0x05,
 227	[OMAP_I2C_CNT_REG] = 0x06,
 228	[OMAP_I2C_DATA_REG] = 0x07,
 229	[OMAP_I2C_SYSC_REG] = 0x08,
 230	[OMAP_I2C_CON_REG] = 0x09,
 231	[OMAP_I2C_OA_REG] = 0x0a,
 232	[OMAP_I2C_SA_REG] = 0x0b,
 233	[OMAP_I2C_PSC_REG] = 0x0c,
 234	[OMAP_I2C_SCLL_REG] = 0x0d,
 235	[OMAP_I2C_SCLH_REG] = 0x0e,
 236	[OMAP_I2C_SYSTEST_REG] = 0x0f,
 237	[OMAP_I2C_BUFSTAT_REG] = 0x10,
 238};
 239
 240static const u8 reg_map_ip_v2[] = {
 241	[OMAP_I2C_REV_REG] = 0x04,
 242	[OMAP_I2C_IE_REG] = 0x2c,
 243	[OMAP_I2C_STAT_REG] = 0x28,
 244	[OMAP_I2C_IV_REG] = 0x34,
 245	[OMAP_I2C_WE_REG] = 0x34,
 246	[OMAP_I2C_SYSS_REG] = 0x90,
 247	[OMAP_I2C_BUF_REG] = 0x94,
 248	[OMAP_I2C_CNT_REG] = 0x98,
 249	[OMAP_I2C_DATA_REG] = 0x9c,
 250	[OMAP_I2C_SYSC_REG] = 0x10,
 251	[OMAP_I2C_CON_REG] = 0xa4,
 252	[OMAP_I2C_OA_REG] = 0xa8,
 253	[OMAP_I2C_SA_REG] = 0xac,
 254	[OMAP_I2C_PSC_REG] = 0xb0,
 255	[OMAP_I2C_SCLL_REG] = 0xb4,
 256	[OMAP_I2C_SCLH_REG] = 0xb8,
 257	[OMAP_I2C_SYSTEST_REG] = 0xbC,
 258	[OMAP_I2C_BUFSTAT_REG] = 0xc0,
 259	[OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
 260	[OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
 261	[OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
 262	[OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
 263	[OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
 264};
 265
 266static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
 267				      int reg, u16 val)
 268{
 269	writew_relaxed(val, i2c_dev->base +
 270			(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 271}
 272
 273static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 274{
 275	return readw_relaxed(i2c_dev->base +
 276				(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 277}
 278
 279static void __omap_i2c_init(struct omap_i2c_dev *dev)
 280{
 
 
 
 
 281
 282	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 
 283
 284	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
 285	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
 286
 287	/* SCL low and high time values */
 288	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
 289	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
 290	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
 
 
 
 291		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
 292
 293	/* Take the I2C module out of reset: */
 294	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 295
 296	/*
 297	 * Don't write to this register if the IE state is 0 as it can
 298	 * cause deadlock.
 299	 */
 300	if (dev->iestate)
 301		omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
 302}
 303
 304static int omap_i2c_reset(struct omap_i2c_dev *dev)
 305{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 306	unsigned long timeout;
 307	u16 sysc;
 308
 309	if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
 310		sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
 311
 
 312		/* Disable I2C controller before soft reset */
 313		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
 314			omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
 315				~(OMAP_I2C_CON_EN));
 316
 317		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
 318		/* For some reason we need to set the EN bit before the
 319		 * reset done bit gets set. */
 320		timeout = jiffies + OMAP_I2C_TIMEOUT;
 321		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 322		while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
 323			 SYSS_RESETDONE_MASK)) {
 324			if (time_after(jiffies, timeout)) {
 325				dev_warn(dev->dev, "timeout waiting "
 326						"for controller reset\n");
 327				return -ETIMEDOUT;
 328			}
 329			msleep(1);
 330		}
 331
 332		/* SYSC register is cleared by the reset; rewrite it */
 333		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
 334
 335	}
 336	return 0;
 337}
 338
 339static int omap_i2c_init(struct omap_i2c_dev *dev)
 340{
 341	u16 psc = 0, scll = 0, sclh = 0;
 342	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
 343	unsigned long fclk_rate = 12000000;
 344	unsigned long internal_clk = 0;
 345	struct clk *fclk;
 346
 347	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
 348		/*
 349		 * Enabling all wakup sources to stop I2C freezing on
 350		 * WFI instruction.
 351		 * REVISIT: Some wkup sources might not be needed.
 352		 */
 353		dev->westate = OMAP_I2C_WE_ALL;
 
 
 
 354	}
 
 355
 356	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
 357		/*
 358		 * The I2C functional clock is the armxor_ck, so there's
 359		 * no need to get "armxor_ck" separately.  Now, if OMAP2420
 360		 * always returns 12MHz for the functional clock, we can
 361		 * do this bit unconditionally.
 362		 */
 363		fclk = clk_get(dev->dev, "fck");
 364		fclk_rate = clk_get_rate(fclk);
 365		clk_put(fclk);
 366
 367		/* TRM for 5912 says the I2C clock must be prescaled to be
 368		 * between 7 - 12 MHz. The XOR input clock is typically
 369		 * 12, 13 or 19.2 MHz. So we should have code that produces:
 370		 *
 371		 * XOR MHz	Divider		Prescaler
 372		 * 12		1		0
 373		 * 13		2		1
 374		 * 19.2		2		1
 375		 */
 376		if (fclk_rate > 12000000)
 377			psc = fclk_rate / 12000000;
 378	}
 379
 380	if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
 381
 382		/*
 383		 * HSI2C controller internal clk rate should be 19.2 Mhz for
 384		 * HS and for all modes on 2430. On 34xx we can use lower rate
 385		 * to get longer filter period for better noise suppression.
 386		 * The filter is iclk (fclk for HS) period.
 387		 */
 388		if (dev->speed > 400 ||
 389			       dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
 390			internal_clk = 19200;
 391		else if (dev->speed > 100)
 392			internal_clk = 9600;
 393		else
 394			internal_clk = 4000;
 395		fclk = clk_get(dev->dev, "fck");
 396		fclk_rate = clk_get_rate(fclk) / 1000;
 397		clk_put(fclk);
 398
 399		/* Compute prescaler divisor */
 400		psc = fclk_rate / internal_clk;
 401		psc = psc - 1;
 402
 403		/* If configured for High Speed */
 404		if (dev->speed > 400) {
 405			unsigned long scl;
 406
 407			/* For first phase of HS mode */
 408			scl = internal_clk / 400;
 409			fsscll = scl - (scl / 3) - 7;
 410			fssclh = (scl / 3) - 5;
 411
 412			/* For second phase of HS mode */
 413			scl = fclk_rate / dev->speed;
 414			hsscll = scl - (scl / 3) - 7;
 415			hssclh = (scl / 3) - 5;
 416		} else if (dev->speed > 100) {
 417			unsigned long scl;
 418
 419			/* Fast mode */
 420			scl = internal_clk / dev->speed;
 421			fsscll = scl - (scl / 3) - 7;
 422			fssclh = (scl / 3) - 5;
 423		} else {
 424			/* Standard mode */
 425			fsscll = internal_clk / (dev->speed * 2) - 7;
 426			fssclh = internal_clk / (dev->speed * 2) - 5;
 427		}
 428		scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
 429		sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
 430	} else {
 431		/* Program desired operating rate */
 432		fclk_rate /= (psc + 1) * 1000;
 433		if (psc > 2)
 434			psc = 2;
 435		scll = fclk_rate / (dev->speed * 2) - 7 + psc;
 436		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
 437	}
 438
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 439	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 440			OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
 441			OMAP_I2C_IE_AL)  | ((dev->fifo_size) ?
 442				(OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
 443
 444	dev->pscstate = psc;
 445	dev->scllstate = scll;
 446	dev->sclhstate = sclh;
 447
 448	__omap_i2c_init(dev);
 449
 450	return 0;
 451}
 452
 453/*
 454 * Waiting on Bus Busy
 455 */
 456static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
 457{
 458	unsigned long timeout;
 459
 460	timeout = jiffies + OMAP_I2C_TIMEOUT;
 461	while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
 462		if (time_after(jiffies, timeout)) {
 463			dev_warn(dev->dev, "timeout waiting for bus ready\n");
 464			return -ETIMEDOUT;
 465		}
 466		msleep(1);
 467	}
 468
 469	return 0;
 470}
 471
 472static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
 473{
 474	u16		buf;
 475
 476	if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
 477		return;
 478
 479	/*
 480	 * Set up notification threshold based on message size. We're doing
 481	 * this to try and avoid draining feature as much as possible. Whenever
 482	 * we have big messages to transfer (bigger than our total fifo size)
 483	 * then we might use draining feature to transfer the remaining bytes.
 484	 */
 485
 486	dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
 487
 488	buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
 489
 490	if (is_rx) {
 491		/* Clear RX Threshold */
 492		buf &= ~(0x3f << 8);
 493		buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
 494	} else {
 495		/* Clear TX Threshold */
 496		buf &= ~0x3f;
 497		buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
 498	}
 499
 500	omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
 501
 502	if (dev->rev < OMAP_I2C_REV_ON_3630)
 503		dev->b_hw = 1; /* Enable hardware fixes */
 504
 505	/* calculate wakeup latency constraint for MPU */
 506	if (dev->set_mpu_wkup_lat != NULL)
 507		dev->latency = (1000000 * dev->threshold) /
 508			(1000 * dev->speed / 8);
 509}
 510
 511/*
 512 * Low level master read/write transaction.
 513 */
 514static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 515			     struct i2c_msg *msg, int stop)
 516{
 517	struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 518	unsigned long timeout;
 519	u16 w;
 520
 521	dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
 522		msg->addr, msg->len, msg->flags, stop);
 523
 524	if (msg->len == 0)
 525		return -EINVAL;
 526
 527	dev->receiver = !!(msg->flags & I2C_M_RD);
 528	omap_i2c_resize_fifo(dev, msg->len, dev->receiver);
 529
 530	omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
 531
 532	/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
 533	dev->buf = msg->buf;
 534	dev->buf_len = msg->len;
 535
 536	/* make sure writes to dev->buf_len are ordered */
 537	barrier();
 538
 539	omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
 540
 541	/* Clear the FIFO Buffers */
 542	w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
 543	w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
 544	omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
 545
 546	reinit_completion(&dev->cmd_complete);
 547	dev->cmd_err = 0;
 548
 549	w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 550
 551	/* High speed configuration */
 552	if (dev->speed > 400)
 553		w |= OMAP_I2C_CON_OPMODE_HS;
 554
 555	if (msg->flags & I2C_M_STOP)
 556		stop = 1;
 557	if (msg->flags & I2C_M_TEN)
 558		w |= OMAP_I2C_CON_XA;
 559	if (!(msg->flags & I2C_M_RD))
 560		w |= OMAP_I2C_CON_TRX;
 561
 562	if (!dev->b_hw && stop)
 563		w |= OMAP_I2C_CON_STP;
 564
 565	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 566
 567	/*
 568	 * Don't write stt and stp together on some hardware.
 569	 */
 570	if (dev->b_hw && stop) {
 571		unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
 572		u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 573		while (con & OMAP_I2C_CON_STT) {
 574			con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 575
 576			/* Let the user know if i2c is in a bad state */
 577			if (time_after(jiffies, delay)) {
 578				dev_err(dev->dev, "controller timed out "
 579				"waiting for start condition to finish\n");
 580				return -ETIMEDOUT;
 581			}
 582			cpu_relax();
 583		}
 584
 585		w |= OMAP_I2C_CON_STP;
 586		w &= ~OMAP_I2C_CON_STT;
 587		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 588	}
 589
 590	/*
 591	 * REVISIT: We should abort the transfer on signals, but the bus goes
 592	 * into arbitration and we're currently unable to recover from it.
 593	 */
 594	timeout = wait_for_completion_timeout(&dev->cmd_complete,
 595						OMAP_I2C_TIMEOUT);
 596	if (timeout == 0) {
 
 
 
 597		dev_err(dev->dev, "controller timed out\n");
 598		omap_i2c_reset(dev);
 599		__omap_i2c_init(dev);
 600		return -ETIMEDOUT;
 601	}
 602
 603	if (likely(!dev->cmd_err))
 604		return 0;
 605
 606	/* We have an error */
 607	if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
 608			    OMAP_I2C_STAT_XUDF)) {
 609		omap_i2c_reset(dev);
 610		__omap_i2c_init(dev);
 611		return -EIO;
 612	}
 613
 614	if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
 615		if (msg->flags & I2C_M_IGNORE_NAK)
 616			return 0;
 617
 618		w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 619		w |= OMAP_I2C_CON_STP;
 620		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 
 621		return -EREMOTEIO;
 622	}
 623	return -EIO;
 624}
 625
 626
 627/*
 628 * Prepare controller for a transaction and call omap_i2c_xfer_msg
 629 * to do the work during IRQ processing.
 630 */
 631static int
 632omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 633{
 634	struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 635	int i;
 636	int r;
 637
 638	r = pm_runtime_get_sync(dev->dev);
 639	if (r < 0)
 640		goto out;
 641
 642	r = omap_i2c_wait_for_bb(dev);
 643	if (r < 0)
 644		goto out;
 645
 646	if (dev->set_mpu_wkup_lat != NULL)
 647		dev->set_mpu_wkup_lat(dev->dev, dev->latency);
 648
 649	for (i = 0; i < num; i++) {
 650		r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
 651		if (r != 0)
 652			break;
 653	}
 654
 
 
 
 655	if (r == 0)
 656		r = num;
 657
 658	omap_i2c_wait_for_bb(dev);
 659
 660	if (dev->set_mpu_wkup_lat != NULL)
 661		dev->set_mpu_wkup_lat(dev->dev, -1);
 662
 663out:
 664	pm_runtime_mark_last_busy(dev->dev);
 665	pm_runtime_put_autosuspend(dev->dev);
 666	return r;
 667}
 668
 669static u32
 670omap_i2c_func(struct i2c_adapter *adap)
 671{
 672	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
 673	       I2C_FUNC_PROTOCOL_MANGLING;
 674}
 675
 676static inline void
 677omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
 678{
 679	dev->cmd_err |= err;
 680	complete(&dev->cmd_complete);
 681}
 682
 683static inline void
 684omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
 685{
 686	omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
 687}
 688
 689static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
 690{
 691	/*
 692	 * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
 693	 * Not applicable for OMAP4.
 694	 * Under certain rare conditions, RDR could be set again
 695	 * when the bus is busy, then ignore the interrupt and
 696	 * clear the interrupt.
 697	 */
 698	if (stat & OMAP_I2C_STAT_RDR) {
 699		/* Step 1: If RDR is set, clear it */
 700		omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 701
 702		/* Step 2: */
 703		if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 704						& OMAP_I2C_STAT_BB)) {
 705
 706			/* Step 3: */
 707			if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 708						& OMAP_I2C_STAT_RDR) {
 709				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 710				dev_dbg(dev->dev, "RDR when bus is busy.\n");
 711			}
 712
 713		}
 714	}
 715}
 716
 717/* rev1 devices are apparently only on some 15xx */
 718#ifdef CONFIG_ARCH_OMAP15XX
 719
 720static irqreturn_t
 721omap_i2c_omap1_isr(int this_irq, void *dev_id)
 722{
 723	struct omap_i2c_dev *dev = dev_id;
 724	u16 iv, w;
 725
 726	if (pm_runtime_suspended(dev->dev))
 727		return IRQ_NONE;
 728
 729	iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
 730	switch (iv) {
 731	case 0x00:	/* None */
 732		break;
 733	case 0x01:	/* Arbitration lost */
 734		dev_err(dev->dev, "Arbitration lost\n");
 735		omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
 736		break;
 737	case 0x02:	/* No acknowledgement */
 738		omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
 739		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
 740		break;
 741	case 0x03:	/* Register access ready */
 742		omap_i2c_complete_cmd(dev, 0);
 743		break;
 744	case 0x04:	/* Receive data ready */
 745		if (dev->buf_len) {
 746			w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 747			*dev->buf++ = w;
 748			dev->buf_len--;
 749			if (dev->buf_len) {
 750				*dev->buf++ = w >> 8;
 751				dev->buf_len--;
 752			}
 753		} else
 754			dev_err(dev->dev, "RRDY IRQ while no data requested\n");
 755		break;
 756	case 0x05:	/* Transmit data ready */
 757		if (dev->buf_len) {
 758			w = *dev->buf++;
 759			dev->buf_len--;
 760			if (dev->buf_len) {
 761				w |= *dev->buf++ << 8;
 762				dev->buf_len--;
 763			}
 764			omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 765		} else
 766			dev_err(dev->dev, "XRDY IRQ while no data to send\n");
 767		break;
 768	default:
 769		return IRQ_NONE;
 770	}
 771
 772	return IRQ_HANDLED;
 773}
 774#else
 775#define omap_i2c_omap1_isr		NULL
 776#endif
 777
 778/*
 779 * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
 780 * data to DATA_REG. Otherwise some data bytes can be lost while transferring
 781 * them from the memory to the I2C interface.
 782 */
 783static int errata_omap3_i462(struct omap_i2c_dev *dev)
 784{
 785	unsigned long timeout = 10000;
 786	u16 stat;
 787
 788	do {
 789		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 790		if (stat & OMAP_I2C_STAT_XUDF)
 791			break;
 792
 793		if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 794			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
 795							OMAP_I2C_STAT_XDR));
 796			if (stat & OMAP_I2C_STAT_NACK) {
 797				dev->cmd_err |= OMAP_I2C_STAT_NACK;
 798				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
 799			}
 800
 801			if (stat & OMAP_I2C_STAT_AL) {
 802				dev_err(dev->dev, "Arbitration lost\n");
 803				dev->cmd_err |= OMAP_I2C_STAT_AL;
 804				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
 805			}
 806
 807			return -EIO;
 808		}
 809
 810		cpu_relax();
 811	} while (--timeout);
 
 812
 813	if (!timeout) {
 814		dev_err(dev->dev, "timeout waiting on XUDF bit\n");
 815		return 0;
 816	}
 817
 818	return 0;
 819}
 820
 821static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
 822		bool is_rdr)
 823{
 824	u16		w;
 825
 826	while (num_bytes--) {
 827		w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 828		*dev->buf++ = w;
 829		dev->buf_len--;
 830
 831		/*
 832		 * Data reg in 2430, omap3 and
 833		 * omap4 is 8 bit wide
 834		 */
 835		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
 836			*dev->buf++ = w >> 8;
 837			dev->buf_len--;
 838		}
 839	}
 840}
 841
 842static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 843		bool is_xdr)
 844{
 845	u16		w;
 846
 847	while (num_bytes--) {
 848		w = *dev->buf++;
 849		dev->buf_len--;
 850
 851		/*
 852		 * Data reg in 2430, omap3 and
 853		 * omap4 is 8 bit wide
 854		 */
 855		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
 856			w |= *dev->buf++ << 8;
 857			dev->buf_len--;
 858		}
 859
 860		if (dev->errata & I2C_OMAP_ERRATA_I462) {
 861			int ret;
 862
 863			ret = errata_omap3_i462(dev);
 864			if (ret < 0)
 865				return ret;
 866		}
 867
 868		omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 869	}
 870
 871	return 0;
 872}
 873
 874static irqreturn_t
 875omap_i2c_isr(int irq, void *dev_id)
 876{
 877	struct omap_i2c_dev *dev = dev_id;
 878	irqreturn_t ret = IRQ_HANDLED;
 879	u16 mask;
 880	u16 stat;
 881
 882	spin_lock(&dev->lock);
 883	mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 884	stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 885
 886	if (stat & mask)
 887		ret = IRQ_WAKE_THREAD;
 888
 889	spin_unlock(&dev->lock);
 890
 891	return ret;
 892}
 893
 894static irqreturn_t
 895omap_i2c_isr_thread(int this_irq, void *dev_id)
 896{
 897	struct omap_i2c_dev *dev = dev_id;
 898	unsigned long flags;
 899	u16 bits;
 900	u16 stat;
 901	int err = 0, count = 0;
 902
 903	spin_lock_irqsave(&dev->lock, flags);
 904	do {
 905		bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 906		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 907		stat &= bits;
 908
 909		/* If we're in receiver mode, ignore XDR/XRDY */
 910		if (dev->receiver)
 911			stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY);
 912		else
 913			stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
 914
 915		if (!stat) {
 916			/* my work here is done */
 917			goto out;
 918		}
 919
 
 
 920		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 921		if (count++ == 100) {
 922			dev_warn(dev->dev, "Too much work in one IRQ\n");
 923			break;
 924		}
 925
 
 
 
 
 
 
 
 
 
 
 
 926		if (stat & OMAP_I2C_STAT_NACK) {
 927			err |= OMAP_I2C_STAT_NACK;
 928			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
 929			break;
 930		}
 931
 932		if (stat & OMAP_I2C_STAT_AL) {
 933			dev_err(dev->dev, "Arbitration lost\n");
 934			err |= OMAP_I2C_STAT_AL;
 935			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
 936			break;
 937		}
 938
 939		/*
 940		 * ProDB0017052: Clear ARDY bit twice
 941		 */
 942		if (stat & OMAP_I2C_STAT_ARDY)
 943			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ARDY);
 944
 945		if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
 946					OMAP_I2C_STAT_AL)) {
 947			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
 948						OMAP_I2C_STAT_RDR |
 949						OMAP_I2C_STAT_XRDY |
 950						OMAP_I2C_STAT_XDR |
 951						OMAP_I2C_STAT_ARDY));
 952			break;
 953		}
 954
 955		if (stat & OMAP_I2C_STAT_RDR) {
 956			u8 num_bytes = 1;
 957
 958			if (dev->fifo_size)
 959				num_bytes = dev->buf_len;
 960
 961			omap_i2c_receive_data(dev, num_bytes, true);
 962
 963			if (dev->errata & I2C_OMAP_ERRATA_I207)
 964				i2c_omap_errata_i207(dev, stat);
 965
 966			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 967			continue;
 968		}
 969
 970		if (stat & OMAP_I2C_STAT_RRDY) {
 971			u8 num_bytes = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 972
 973			if (dev->threshold)
 974				num_bytes = dev->threshold;
 975
 976			omap_i2c_receive_data(dev, num_bytes, false);
 977			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
 978			continue;
 979		}
 980
 981		if (stat & OMAP_I2C_STAT_XDR) {
 982			u8 num_bytes = 1;
 983			int ret;
 984
 985			if (dev->fifo_size)
 986				num_bytes = dev->buf_len;
 987
 988			ret = omap_i2c_transmit_data(dev, num_bytes, true);
 989			if (ret < 0)
 990				break;
 991
 992			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
 993			continue;
 994		}
 995
 996		if (stat & OMAP_I2C_STAT_XRDY) {
 997			u8 num_bytes = 1;
 998			int ret;
 999
1000			if (dev->threshold)
1001				num_bytes = dev->threshold;
1002
1003			ret = omap_i2c_transmit_data(dev, num_bytes, false);
1004			if (ret < 0)
1005				break;
1006
1007			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
1008			continue;
1009		}
1010
1011		if (stat & OMAP_I2C_STAT_ROVR) {
1012			dev_err(dev->dev, "Receive overrun\n");
1013			err |= OMAP_I2C_STAT_ROVR;
1014			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
1015			break;
1016		}
1017
1018		if (stat & OMAP_I2C_STAT_XUDF) {
1019			dev_err(dev->dev, "Transmit underflow\n");
1020			err |= OMAP_I2C_STAT_XUDF;
1021			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
1022			break;
1023		}
1024	} while (stat);
1025
1026	omap_i2c_complete_cmd(dev, err);
1027
1028out:
1029	spin_unlock_irqrestore(&dev->lock, flags);
1030
1031	return IRQ_HANDLED;
1032}
1033
1034static const struct i2c_algorithm omap_i2c_algo = {
1035	.master_xfer	= omap_i2c_xfer,
1036	.functionality	= omap_i2c_func,
1037};
1038
1039#ifdef CONFIG_OF
1040static struct omap_i2c_bus_platform_data omap2420_pdata = {
1041	.rev = OMAP_I2C_IP_VERSION_1,
1042	.flags = OMAP_I2C_FLAG_NO_FIFO |
1043			OMAP_I2C_FLAG_SIMPLE_CLOCK |
1044			OMAP_I2C_FLAG_16BIT_DATA_REG |
1045			OMAP_I2C_FLAG_BUS_SHIFT_2,
1046};
1047
1048static struct omap_i2c_bus_platform_data omap2430_pdata = {
1049	.rev = OMAP_I2C_IP_VERSION_1,
1050	.flags = OMAP_I2C_FLAG_BUS_SHIFT_2 |
1051			OMAP_I2C_FLAG_FORCE_19200_INT_CLK,
1052};
1053
1054static struct omap_i2c_bus_platform_data omap3_pdata = {
1055	.rev = OMAP_I2C_IP_VERSION_1,
1056	.flags = OMAP_I2C_FLAG_BUS_SHIFT_2,
1057};
1058
1059static struct omap_i2c_bus_platform_data omap4_pdata = {
1060	.rev = OMAP_I2C_IP_VERSION_2,
1061};
1062
1063static const struct of_device_id omap_i2c_of_match[] = {
1064	{
1065		.compatible = "ti,omap4-i2c",
1066		.data = &omap4_pdata,
1067	},
1068	{
1069		.compatible = "ti,omap3-i2c",
1070		.data = &omap3_pdata,
1071	},
1072	{
1073		.compatible = "ti,omap2430-i2c",
1074		.data = &omap2430_pdata,
1075	},
1076	{
1077		.compatible = "ti,omap2420-i2c",
1078		.data = &omap2420_pdata,
1079	},
1080	{ },
1081};
1082MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
1083#endif
1084
1085#define OMAP_I2C_SCHEME(rev)		((rev & 0xc000) >> 14)
1086
1087#define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4)
1088#define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf)
1089
1090#define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7)
1091#define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f)
1092#define OMAP_I2C_SCHEME_0		0
1093#define OMAP_I2C_SCHEME_1		1
1094
1095static int
1096omap_i2c_probe(struct platform_device *pdev)
1097{
1098	struct omap_i2c_dev	*dev;
1099	struct i2c_adapter	*adap;
1100	struct resource		*mem;
1101	const struct omap_i2c_bus_platform_data *pdata =
1102		dev_get_platdata(&pdev->dev);
1103	struct device_node	*node = pdev->dev.of_node;
1104	const struct of_device_id *match;
1105	int irq;
1106	int r;
1107	u32 rev;
1108	u16 minor, major;
1109
1110	irq = platform_get_irq(pdev, 0);
1111	if (irq < 0) {
 
 
 
 
 
 
1112		dev_err(&pdev->dev, "no irq resource?\n");
1113		return irq;
1114	}
1115
1116	dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
 
 
 
 
 
 
 
1117	if (!dev) {
1118		dev_err(&pdev->dev, "Menory allocation failed\n");
1119		return -ENOMEM;
1120	}
1121
1122	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1123	dev->base = devm_ioremap_resource(&pdev->dev, mem);
1124	if (IS_ERR(dev->base))
1125		return PTR_ERR(dev->base);
1126
1127	match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
1128	if (match) {
1129		u32 freq = 100000; /* default to 100000 Hz */
1130
1131		pdata = match->data;
1132		dev->flags = pdata->flags;
1133
1134		of_property_read_u32(node, "clock-frequency", &freq);
1135		/* convert DT freq value in Hz into kHz for speed */
1136		dev->speed = freq / 1000;
1137	} else if (pdata != NULL) {
1138		dev->speed = pdata->clkrate;
1139		dev->flags = pdata->flags;
1140		dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
 
 
 
1141	}
1142
 
 
1143	dev->dev = &pdev->dev;
1144	dev->irq = irq;
1145
1146	spin_lock_init(&dev->lock);
 
 
 
1147
1148	platform_set_drvdata(pdev, dev);
1149	init_completion(&dev->cmd_complete);
1150
1151	dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
 
 
 
 
 
1152
1153	pm_runtime_enable(dev->dev);
1154	pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT);
1155	pm_runtime_use_autosuspend(dev->dev);
 
1156
1157	r = pm_runtime_get_sync(dev->dev);
1158	if (r < 0)
1159		goto err_free_mem;
1160
1161	/*
1162	 * Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2.
1163	 * On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset.
1164	 * Also since the omap_i2c_read_reg uses reg_map_ip_* a
1165	 * readw_relaxed is done.
1166	 */
1167	rev = readw_relaxed(dev->base + 0x04);
1168
1169	dev->scheme = OMAP_I2C_SCHEME(rev);
1170	switch (dev->scheme) {
1171	case OMAP_I2C_SCHEME_0:
1172		dev->regs = (u8 *)reg_map_ip_v1;
1173		dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG);
1174		minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
1175		major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
1176		break;
1177	case OMAP_I2C_SCHEME_1:
1178		/* FALLTHROUGH */
1179	default:
1180		dev->regs = (u8 *)reg_map_ip_v2;
1181		rev = (rev << 16) |
1182			omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO);
1183		minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev);
1184		major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev);
1185		dev->rev = rev;
1186	}
1187
1188	dev->errata = 0;
1189
1190	if (dev->rev >= OMAP_I2C_REV_ON_2430 &&
1191			dev->rev < OMAP_I2C_REV_ON_4430_PLUS)
1192		dev->errata |= I2C_OMAP_ERRATA_I207;
1193
1194	if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
1195		dev->errata |= I2C_OMAP_ERRATA_I462;
1196
1197	if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
1198		u16 s;
1199
1200		/* Set up the fifo size - Get total size */
1201		s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1202		dev->fifo_size = 0x8 << s;
1203
1204		/*
1205		 * Set up notification threshold as half the total available
1206		 * size. This is to ensure that we can handle the status on int
1207		 * call back latencies.
1208		 */
1209
1210		dev->fifo_size = (dev->fifo_size / 2);
1211
1212		if (dev->rev < OMAP_I2C_REV_ON_3630)
 
1213			dev->b_hw = 1; /* Enable hardware fixes */
1214
1215		/* calculate wakeup latency constraint for MPU */
1216		if (dev->set_mpu_wkup_lat != NULL)
1217			dev->latency = (1000000 * dev->fifo_size) /
1218				       (1000 * dev->speed / 8);
1219	}
1220
1221	/* reset ASAP, clearing any IRQs */
1222	omap_i2c_init(dev);
1223
1224	if (dev->rev < OMAP_I2C_OMAP1_REV_2)
1225		r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr,
1226				IRQF_NO_SUSPEND, pdev->name, dev);
1227	else
1228		r = devm_request_threaded_irq(&pdev->dev, dev->irq,
1229				omap_i2c_isr, omap_i2c_isr_thread,
1230				IRQF_NO_SUSPEND | IRQF_ONESHOT,
1231				pdev->name, dev);
1232
1233	if (r) {
1234		dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1235		goto err_unuse_clocks;
1236	}
1237
 
 
 
 
 
1238	adap = &dev->adapter;
1239	i2c_set_adapdata(adap, dev);
1240	adap->owner = THIS_MODULE;
1241	adap->class = I2C_CLASS_HWMON | I2C_CLASS_DEPRECATED;
1242	strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
1243	adap->algo = &omap_i2c_algo;
1244	adap->dev.parent = &pdev->dev;
1245	adap->dev.of_node = pdev->dev.of_node;
1246
1247	/* i2c device drivers may be active on return from add_adapter() */
1248	adap->nr = pdev->id;
1249	r = i2c_add_numbered_adapter(adap);
1250	if (r) {
1251		dev_err(dev->dev, "failure adding adapter\n");
1252		goto err_unuse_clocks;
1253	}
1254
1255	dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
1256		 major, minor, dev->speed);
1257
1258	pm_runtime_mark_last_busy(dev->dev);
1259	pm_runtime_put_autosuspend(dev->dev);
1260
1261	return 0;
1262
 
 
1263err_unuse_clocks:
1264	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1265	pm_runtime_put(dev->dev);
1266	pm_runtime_disable(&pdev->dev);
1267err_free_mem:
 
 
 
 
1268
1269	return r;
1270}
1271
1272static int omap_i2c_remove(struct platform_device *pdev)
 
1273{
1274	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
1275	int ret;
1276
 
 
 
1277	i2c_del_adapter(&dev->adapter);
1278	ret = pm_runtime_get_sync(&pdev->dev);
1279	if (ret < 0)
1280		return ret;
1281
1282	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1283	pm_runtime_put(&pdev->dev);
1284	pm_runtime_disable(&pdev->dev);
1285	return 0;
1286}
1287
1288#ifdef CONFIG_PM
1289#ifdef CONFIG_PM_RUNTIME
1290static int omap_i2c_runtime_suspend(struct device *dev)
1291{
1292	struct platform_device *pdev = to_platform_device(dev);
1293	struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1294
1295	_dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
1296
1297	if (_dev->scheme == OMAP_I2C_SCHEME_0)
1298		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
1299	else
1300		omap_i2c_write_reg(_dev, OMAP_I2C_IP_V2_IRQENABLE_CLR,
1301				   OMAP_I2C_IP_V2_INTERRUPTS_MASK);
1302
1303	if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
1304		omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
1305	} else {
1306		omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
1307
1308		/* Flush posted write */
1309		omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
1310	}
1311
1312	return 0;
1313}
1314
1315static int omap_i2c_runtime_resume(struct device *dev)
1316{
1317	struct platform_device *pdev = to_platform_device(dev);
1318	struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1319
1320	if (!_dev->regs)
1321		return 0;
1322
1323	__omap_i2c_init(_dev);
1324
1325	return 0;
1326}
1327#endif /* CONFIG_PM_RUNTIME */
1328
1329static struct dev_pm_ops omap_i2c_pm_ops = {
1330	SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
1331			   omap_i2c_runtime_resume, NULL)
1332};
1333#define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1334#else
1335#define OMAP_I2C_PM_OPS NULL
1336#endif /* CONFIG_PM */
1337
1338static struct platform_driver omap_i2c_driver = {
1339	.probe		= omap_i2c_probe,
1340	.remove		= omap_i2c_remove,
1341	.driver		= {
1342		.name	= "omap_i2c",
1343		.owner	= THIS_MODULE,
1344		.pm	= OMAP_I2C_PM_OPS,
1345		.of_match_table = of_match_ptr(omap_i2c_of_match),
1346	},
1347};
1348
1349/* I2C may be needed to bring up other drivers */
1350static int __init
1351omap_i2c_init_driver(void)
1352{
1353	return platform_driver_register(&omap_i2c_driver);
1354}
1355subsys_initcall(omap_i2c_init_driver);
1356
1357static void __exit omap_i2c_exit_driver(void)
1358{
1359	platform_driver_unregister(&omap_i2c_driver);
1360}
1361module_exit(omap_i2c_exit_driver);
1362
1363MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1364MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1365MODULE_LICENSE("GPL");
1366MODULE_ALIAS("platform:omap_i2c");