Linux Audio

Check our new training course

Linux kernel drivers training

Mar 31-Apr 9, 2025, special US time zones
Register
Loading...
v3.1
 
  1/*
  2 *	Copyright (C) 2002 Motorola GSG-China
  3 *
  4 *	This program is free software; you can redistribute it and/or
  5 *	modify it under the terms of the GNU General Public License
  6 *	as published by the Free Software Foundation; either version 2
  7 *	of the License, or (at your option) any later version.
  8 *
  9 *	This program is distributed in the hope that it will be useful,
 10 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
 11 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 12 *	GNU General Public License for more details.
 13 *
 14 *	You should have received a copy of the GNU General Public License
 15 *	along with this program; if not, write to the Free Software
 16 *	Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
 17 *	USA.
 18 *
 19 * Author:
 20 *	Darius Augulis, Teltonika Inc.
 21 *
 22 * Desc.:
 23 *	Implementation of I2C Adapter/Algorithm Driver
 24 *	for I2C Bus integrated in Freescale i.MX/MXC processors
 25 *
 26 *	Derived from Motorola GSG China I2C example driver
 27 *
 28 *	Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de
 29 *	Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de
 30 *	Copyright (C) 2007 RightHand Technologies, Inc.
 31 *	Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
 32 *
 
 
 
 33 */
 34
 35/** Includes *******************************************************************
 36*******************************************************************************/
 37
 38#include <linux/init.h>
 39#include <linux/kernel.h>
 40#include <linux/module.h>
 41#include <linux/errno.h>
 42#include <linux/err.h>
 43#include <linux/interrupt.h>
 44#include <linux/delay.h>
 
 
 
 
 
 
 45#include <linux/i2c.h>
 
 
 46#include <linux/io.h>
 47#include <linux/sched.h>
 
 
 
 
 
 
 
 
 
 48#include <linux/platform_device.h>
 49#include <linux/clk.h>
 
 50#include <linux/slab.h>
 51
 52#include <mach/irqs.h>
 53#include <mach/hardware.h>
 54#include <mach/i2c.h>
 55
 56/** Defines ********************************************************************
 57*******************************************************************************/
 58
 59/* This will be the driver name the kernel reports */
 60#define DRIVER_NAME "imx-i2c"
 61
 62/* Default value */
 63#define IMX_I2C_BIT_RATE	100000	/* 100kHz */
 64
 65/* IMX I2C registers */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 66#define IMX_I2C_IADR	0x00	/* i2c slave address */
 67#define IMX_I2C_IFDR	0x04	/* i2c frequency divider */
 68#define IMX_I2C_I2CR	0x08	/* i2c control */
 69#define IMX_I2C_I2SR	0x0C	/* i2c status */
 70#define IMX_I2C_I2DR	0x10	/* i2c transfer data */
 
 
 
 
 
 
 
 
 71
 72/* Bits of IMX I2C registers */
 73#define I2SR_RXAK	0x01
 74#define I2SR_IIF	0x02
 75#define I2SR_SRW	0x04
 76#define I2SR_IAL	0x10
 77#define I2SR_IBB	0x20
 78#define I2SR_IAAS	0x40
 79#define I2SR_ICF	0x80
 
 80#define I2CR_RSTA	0x04
 81#define I2CR_TXAK	0x08
 82#define I2CR_MTX	0x10
 83#define I2CR_MSTA	0x20
 84#define I2CR_IIEN	0x40
 85#define I2CR_IEN	0x80
 
 86
 87/** Variables ******************************************************************
 88*******************************************************************************/
 
 
 
 
 
 
 
 
 
 
 
 
 89
 90/*
 91 * sorted list of clock divider, register value pairs
 92 * taken from table 26-5, p.26-9, Freescale i.MX
 93 * Integrated Portable System Processor Reference Manual
 94 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
 95 *
 96 * Duplicated divider values removed from list
 97 */
 
 
 
 
 98
 99static u16 __initdata i2c_clk_div[50][2] = {
100	{ 22,	0x20 }, { 24,	0x21 }, { 26,	0x22 }, { 28,	0x23 },
101	{ 30,	0x00 },	{ 32,	0x24 }, { 36,	0x25 }, { 40,	0x26 },
102	{ 42,	0x03 }, { 44,	0x27 },	{ 48,	0x28 }, { 52,	0x05 },
103	{ 56,	0x29 }, { 60,	0x06 }, { 64,	0x2A },	{ 72,	0x2B },
104	{ 80,	0x2C }, { 88,	0x09 }, { 96,	0x2D }, { 104,	0x0A },
105	{ 112,	0x2E }, { 128,	0x2F }, { 144,	0x0C }, { 160,	0x30 },
106	{ 192,	0x31 },	{ 224,	0x32 }, { 240,	0x0F }, { 256,	0x33 },
107	{ 288,	0x10 }, { 320,	0x34 },	{ 384,	0x35 }, { 448,	0x36 },
108	{ 480,	0x13 }, { 512,	0x37 }, { 576,	0x14 },	{ 640,	0x38 },
109	{ 768,	0x39 }, { 896,	0x3A }, { 960,	0x17 }, { 1024,	0x3B },
110	{ 1152,	0x18 }, { 1280,	0x3C }, { 1536,	0x3D }, { 1792,	0x3E },
111	{ 1920,	0x1B },	{ 2048,	0x3F }, { 2304,	0x1C }, { 2560,	0x1D },
112	{ 3072,	0x1E }, { 3840,	0x1F }
113};
114
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
115struct imx_i2c_struct {
116	struct i2c_adapter	adapter;
117	struct resource		*res;
118	struct clk		*clk;
 
119	void __iomem		*base;
120	int			irq;
121	wait_queue_head_t	queue;
122	unsigned long		i2csr;
123	unsigned int 		disable_delay;
124	int			stopped;
125	unsigned int		ifdr; /* IMX_I2C_IFDR */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
126};
127
128/** Functions for IMX I2C adapter driver ***************************************
129*******************************************************************************/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
130
131static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
132{
133	unsigned long orig_jiffies = jiffies;
134	unsigned int temp;
135
136	dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
137
138	while (1) {
139		temp = readb(i2c_imx->base + IMX_I2C_I2SR);
140		if (for_busy && (temp & I2SR_IBB))
 
 
 
 
 
 
 
 
141			break;
142		if (!for_busy && !(temp & I2SR_IBB))
 
 
143			break;
144		if (signal_pending(current)) {
145			dev_dbg(&i2c_imx->adapter.dev,
146				"<%s> I2C Interrupted\n", __func__);
147			return -EINTR;
148		}
149		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
150			dev_dbg(&i2c_imx->adapter.dev,
151				"<%s> I2C bus is busy\n", __func__);
152			return -ETIMEDOUT;
153		}
154		schedule();
 
 
 
155	}
156
157	return 0;
158}
159
160static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
161{
162	wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
163
164	if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
165		dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
166		return -ETIMEDOUT;
167	}
 
 
 
 
 
 
 
 
 
 
168	dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
169	i2c_imx->i2csr = 0;
170	return 0;
171}
172
173static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
174{
175	if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
176		dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
177		return -EIO;  /* No ACK */
178	}
179
180	dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
181	return 0;
182}
183
184static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
185{
186	unsigned int temp = 0;
187	int result;
188
189	dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
190
191	clk_enable(i2c_imx->clk);
192	writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
193	/* Enable I2C controller */
194	writeb(0, i2c_imx->base + IMX_I2C_I2SR);
195	writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
196
197	/* Wait controller to be stable */
198	udelay(50);
 
 
 
199
200	/* Start I2C transaction */
201	temp = readb(i2c_imx->base + IMX_I2C_I2CR);
202	temp |= I2CR_MSTA;
203	writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
204	result = i2c_imx_bus_busy(i2c_imx, 1);
205	if (result)
206		return result;
207	i2c_imx->stopped = 0;
208
209	temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
210	writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
 
 
 
 
211	return result;
212}
213
214static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
215{
216	unsigned int temp = 0;
217
218	if (!i2c_imx->stopped) {
219		/* Stop I2C transaction */
220		dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
221		temp = readb(i2c_imx->base + IMX_I2C_I2CR);
 
222		temp &= ~(I2CR_MSTA | I2CR_MTX);
223		writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
 
 
224	}
225	if (cpu_is_mx1()) {
226		/*
227		 * This delay caused by an i.MXL hardware bug.
228		 * If no (or too short) delay, no "STOP" bit will be generated.
229		 */
230		udelay(i2c_imx->disable_delay);
231	}
232
233	if (!i2c_imx->stopped) {
234		i2c_imx_bus_busy(i2c_imx, 0);
235		i2c_imx->stopped = 1;
236	}
237
238	/* Disable I2C controller */
239	writeb(0, i2c_imx->base + IMX_I2C_I2CR);
240	clk_disable(i2c_imx->clk);
241}
242
243static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
244							unsigned int rate)
 
 
 
 
245{
246	unsigned int i2c_clk_rate;
247	unsigned int div;
248	int i;
249
250	/* Divider value calculation */
251	i2c_clk_rate = clk_get_rate(i2c_imx->clk);
252	div = (i2c_clk_rate + rate - 1) / rate;
253	if (div < i2c_clk_div[0][0])
254		i = 0;
255	else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
256		i = ARRAY_SIZE(i2c_clk_div) - 1;
257	else
258		for (i = 0; i2c_clk_div[i][0] < div; i++);
259
260	/* Store divider value */
261	i2c_imx->ifdr = i2c_clk_div[i][1];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
262
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
263	/*
264	 * There dummy delay is calculated.
265	 * It should be about one I2C clock period long.
266	 * This delay is used in I2C bus disable function
267	 * to fix chip hardware bug.
 
268	 */
269	i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
270		+ (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
 
 
 
271
272	/* dev_dbg() can't be used, because adapter is not yet registered */
273#ifdef CONFIG_I2C_DEBUG_BUS
274	printk(KERN_DEBUG "I2C: <%s> I2C_CLK=%d, REQ DIV=%d\n",
275		__func__, i2c_clk_rate, div);
276	printk(KERN_DEBUG "I2C: <%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
277		__func__, i2c_clk_div[i][1], i2c_clk_div[i][0]);
278#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
279}
280
281static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
282{
283	struct imx_i2c_struct *i2c_imx = dev_id;
284	unsigned int temp;
 
285
286	temp = readb(i2c_imx->base + IMX_I2C_I2SR);
287	if (temp & I2SR_IIF) {
288		/* save status register */
289		i2c_imx->i2csr = temp;
290		temp &= ~I2SR_IIF;
291		writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
292		wake_up(&i2c_imx->queue);
293		return IRQ_HANDLED;
 
 
 
 
 
 
 
 
 
 
 
 
294	}
 
295
296	return IRQ_NONE;
297}
298
299static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
300{
301	int i, result;
302
303	dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
304		__func__, msgs->addr << 1);
305
306	/* write slave address */
307	writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR);
308	result = i2c_imx_trx_complete(i2c_imx);
309	if (result)
310		return result;
311	result = i2c_imx_acked(i2c_imx);
312	if (result)
313		return result;
314	dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
315
316	/* write data */
317	for (i = 0; i < msgs->len; i++) {
318		dev_dbg(&i2c_imx->adapter.dev,
319			"<%s> write byte: B%d=0x%X\n",
320			__func__, i, msgs->buf[i]);
321		writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
322		result = i2c_imx_trx_complete(i2c_imx);
323		if (result)
324			return result;
325		result = i2c_imx_acked(i2c_imx);
326		if (result)
327			return result;
328	}
329	return 0;
330}
331
332static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 
333{
334	int i, result;
335	unsigned int temp;
 
 
 
336
337	dev_dbg(&i2c_imx->adapter.dev,
338		"<%s> write slave address: addr=0x%x\n",
339		__func__, (msgs->addr << 1) | 0x01);
340
341	/* write slave address */
342	writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR);
343	result = i2c_imx_trx_complete(i2c_imx);
344	if (result)
345		return result;
346	result = i2c_imx_acked(i2c_imx);
347	if (result)
348		return result;
349
350	dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
351
352	/* setup bus to read data */
353	temp = readb(i2c_imx->base + IMX_I2C_I2CR);
354	temp &= ~I2CR_MTX;
355	if (msgs->len - 1)
 
 
 
 
 
356		temp &= ~I2CR_TXAK;
357	writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
358	readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
 
 
359
360	dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
361
 
 
 
362	/* read data */
363	for (i = 0; i < msgs->len; i++) {
364		result = i2c_imx_trx_complete(i2c_imx);
 
 
365		if (result)
366			return result;
367		if (i == (msgs->len - 1)) {
368			/* It must generate STOP before read I2DR to prevent
369			   controller from generating another clock cycle */
 
 
 
 
 
 
370			dev_dbg(&i2c_imx->adapter.dev,
371				"<%s> clear MSTA\n", __func__);
372			temp = readb(i2c_imx->base + IMX_I2C_I2CR);
373			temp &= ~(I2CR_MSTA | I2CR_MTX);
374			writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
375			i2c_imx_bus_busy(i2c_imx, 0);
376			i2c_imx->stopped = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
377		} else if (i == (msgs->len - 2)) {
378			dev_dbg(&i2c_imx->adapter.dev,
379				"<%s> set TXAK\n", __func__);
380			temp = readb(i2c_imx->base + IMX_I2C_I2CR);
381			temp |= I2CR_TXAK;
382			writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
383		}
384		msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
 
 
 
385		dev_dbg(&i2c_imx->adapter.dev,
386			"<%s> read byte: B%d=0x%X\n",
387			__func__, i, msgs->buf[i]);
388	}
389	return 0;
390}
391
392static int i2c_imx_xfer(struct i2c_adapter *adapter,
393						struct i2c_msg *msgs, int num)
394{
395	unsigned int i, temp;
396	int result;
 
397	struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
398
399	dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
400
401	/* Start I2C transfer */
402	result = i2c_imx_start(i2c_imx);
 
 
 
 
 
 
 
 
 
 
 
403	if (result)
404		goto fail0;
405
406	/* read/write data */
407	for (i = 0; i < num; i++) {
 
 
 
408		if (i) {
409			dev_dbg(&i2c_imx->adapter.dev,
410				"<%s> repeated start\n", __func__);
411			temp = readb(i2c_imx->base + IMX_I2C_I2CR);
412			temp |= I2CR_RSTA;
413			writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
414			result =  i2c_imx_bus_busy(i2c_imx, 1);
415			if (result)
416				goto fail0;
417		}
418		dev_dbg(&i2c_imx->adapter.dev,
419			"<%s> transfer message: %d\n", __func__, i);
420		/* write/read data */
421#ifdef CONFIG_I2C_DEBUG_BUS
422		temp = readb(i2c_imx->base + IMX_I2C_I2CR);
423		dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, "
424			"MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__,
 
425			(temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
426			(temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
427			(temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
428		temp = readb(i2c_imx->base + IMX_I2C_I2SR);
429		dev_dbg(&i2c_imx->adapter.dev,
430			"<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, "
431			"IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__,
432			(temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
433			(temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
434			(temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
435			(temp & I2SR_RXAK ? 1 : 0));
436#endif
437		if (msgs[i].flags & I2C_M_RD)
438			result = i2c_imx_read(i2c_imx, &msgs[i]);
439		else
440			result = i2c_imx_write(i2c_imx, &msgs[i]);
 
 
 
 
 
 
441		if (result)
442			goto fail0;
443	}
444
445fail0:
446	/* Stop I2C transfer */
447	i2c_imx_stop(i2c_imx);
448
449	dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
450		(result < 0) ? "error" : "success msg",
451			(result < 0) ? result : num);
 
 
 
 
452	return (result < 0) ? result : num;
453}
454
455static u32 i2c_imx_func(struct i2c_adapter *adapter)
 
456{
457	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 
 
 
 
 
 
 
 
 
 
 
 
458}
459
460static struct i2c_algorithm i2c_imx_algo = {
461	.master_xfer	= i2c_imx_xfer,
462	.functionality	= i2c_imx_func,
463};
 
 
 
 
 
 
 
 
 
464
465static int __init i2c_imx_probe(struct platform_device *pdev)
 
 
 
466{
467	struct imx_i2c_struct *i2c_imx;
468	struct resource *res;
469	struct imxi2c_platform_data *pdata;
470	void __iomem *base;
471	resource_size_t res_size;
472	int irq;
473	int ret;
474
475	dev_dbg(&pdev->dev, "<%s>\n", __func__);
476
477	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
478	if (!res) {
479		dev_err(&pdev->dev, "can't get device resources\n");
480		return -ENOENT;
481	}
482	irq = platform_get_irq(pdev, 0);
483	if (irq < 0) {
484		dev_err(&pdev->dev, "can't get irq number\n");
485		return -ENOENT;
486	}
487
488	pdata = pdev->dev.platform_data;
 
 
489
490	if (pdata && pdata->init) {
491		ret = pdata->init(&pdev->dev);
492		if (ret)
493			return ret;
494	}
495
496	res_size = resource_size(res);
 
497
498	if (!request_mem_region(res->start, res_size, DRIVER_NAME)) {
499		ret = -EBUSY;
500		goto fail0;
501	}
 
 
 
 
 
 
 
502
503	base = ioremap(res->start, res_size);
504	if (!base) {
505		dev_err(&pdev->dev, "ioremap failed\n");
506		ret = -EIO;
507		goto fail1;
508	}
509
510	i2c_imx = kzalloc(sizeof(struct imx_i2c_struct), GFP_KERNEL);
511	if (!i2c_imx) {
512		dev_err(&pdev->dev, "can't allocate interface\n");
513		ret = -ENOMEM;
514		goto fail2;
 
 
 
 
 
 
 
 
 
 
 
515	}
516
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
517	/* Setup i2c_imx driver structure */
518	strcpy(i2c_imx->adapter.name, pdev->name);
519	i2c_imx->adapter.owner		= THIS_MODULE;
520	i2c_imx->adapter.algo		= &i2c_imx_algo;
521	i2c_imx->adapter.dev.parent	= &pdev->dev;
522	i2c_imx->adapter.nr 		= pdev->id;
523	i2c_imx->irq			= irq;
524	i2c_imx->base			= base;
525	i2c_imx->res			= res;
526
527	/* Get I2C clock */
528	i2c_imx->clk = clk_get(&pdev->dev, "i2c_clk");
529	if (IS_ERR(i2c_imx->clk)) {
530		ret = PTR_ERR(i2c_imx->clk);
531		dev_err(&pdev->dev, "can't get I2C clock\n");
532		goto fail3;
533	}
534
535	/* Request IRQ */
536	ret = request_irq(i2c_imx->irq, i2c_imx_isr, 0, pdev->name, i2c_imx);
537	if (ret) {
538		dev_err(&pdev->dev, "can't claim irq %d\n", i2c_imx->irq);
539		goto fail4;
540	}
541
542	/* Init queue */
543	init_waitqueue_head(&i2c_imx->queue);
544
545	/* Set up adapter data */
546	i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
547
548	/* Set up clock divider */
549	if (pdata && pdata->bitrate)
550		i2c_imx_set_clk(i2c_imx, pdata->bitrate);
551	else
552		i2c_imx_set_clk(i2c_imx, IMX_I2C_BIT_RATE);
553
554	/* Set up chip registers to defaults */
555	writeb(0, i2c_imx->base + IMX_I2C_I2CR);
556	writeb(0, i2c_imx->base + IMX_I2C_I2SR);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
557
558	/* Add I2C adapter */
559	ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
560	if (ret < 0) {
561		dev_err(&pdev->dev, "registration failed\n");
562		goto fail5;
563	}
564
565	/* Set up platform driver data */
566	platform_set_drvdata(pdev, i2c_imx);
567
568	dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", i2c_imx->irq);
569	dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n",
570		i2c_imx->res->start, i2c_imx->res->end);
571	dev_dbg(&i2c_imx->adapter.dev, "allocated %d bytes at 0x%x \n",
572		res_size, i2c_imx->res->start);
573	dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
574		i2c_imx->adapter.name);
575	dev_dbg(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
 
 
 
576
577	return 0;   /* Return OK */
578
579fail5:
580	free_irq(i2c_imx->irq, i2c_imx);
581fail4:
582	clk_put(i2c_imx->clk);
583fail3:
584	kfree(i2c_imx);
585fail2:
586	iounmap(base);
587fail1:
588	release_mem_region(res->start, resource_size(res));
589fail0:
590	if (pdata && pdata->exit)
591		pdata->exit(&pdev->dev);
592	return ret; /* Return error number */
593}
594
595static int __exit i2c_imx_remove(struct platform_device *pdev)
596{
597	struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
598	struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
 
 
 
 
599
600	/* remove adapter */
601	dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
602	i2c_del_adapter(&i2c_imx->adapter);
603	platform_set_drvdata(pdev, NULL);
604
605	/* free interrupt */
606	free_irq(i2c_imx->irq, i2c_imx);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
607
608	/* setup chip registers to defaults */
609	writeb(0, i2c_imx->base + IMX_I2C_IADR);
610	writeb(0, i2c_imx->base + IMX_I2C_IFDR);
611	writeb(0, i2c_imx->base + IMX_I2C_I2CR);
612	writeb(0, i2c_imx->base + IMX_I2C_I2SR);
613
614	/* Shut down hardware */
615	if (pdata && pdata->exit)
616		pdata->exit(&pdev->dev);
617
618	clk_put(i2c_imx->clk);
619
620	iounmap(i2c_imx->base);
621	release_mem_region(i2c_imx->res->start, resource_size(i2c_imx->res));
622	kfree(i2c_imx);
623	return 0;
624}
625
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
626static struct platform_driver i2c_imx_driver = {
627	.remove		= __exit_p(i2c_imx_remove),
628	.driver	= {
629		.name	= DRIVER_NAME,
630		.owner	= THIS_MODULE,
631	}
 
 
 
 
632};
633
634static int __init i2c_adap_imx_init(void)
635{
636	return platform_driver_probe(&i2c_imx_driver, i2c_imx_probe);
637}
638subsys_initcall(i2c_adap_imx_init);
639
640static void __exit i2c_adap_imx_exit(void)
641{
642	platform_driver_unregister(&i2c_imx_driver);
643}
644module_exit(i2c_adap_imx_exit);
645
646MODULE_LICENSE("GPL");
647MODULE_AUTHOR("Darius Augulis");
648MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
649MODULE_ALIAS("platform:" DRIVER_NAME);
v6.2
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *	Copyright (C) 2002 Motorola GSG-China
   4 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   5 * Author:
   6 *	Darius Augulis, Teltonika Inc.
   7 *
   8 * Desc.:
   9 *	Implementation of I2C Adapter/Algorithm Driver
  10 *	for I2C Bus integrated in Freescale i.MX/MXC processors
  11 *
  12 *	Derived from Motorola GSG China I2C example driver
  13 *
  14 *	Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de
  15 *	Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de
  16 *	Copyright (C) 2007 RightHand Technologies, Inc.
  17 *	Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
  18 *
  19 *	Copyright 2013 Freescale Semiconductor, Inc.
  20 *	Copyright 2020 NXP
  21 *
  22 */
  23
  24#include <linux/acpi.h>
  25#include <linux/clk.h>
  26#include <linux/completion.h>
 
 
 
 
 
 
  27#include <linux/delay.h>
  28#include <linux/dma-mapping.h>
  29#include <linux/dmaengine.h>
  30#include <linux/dmapool.h>
  31#include <linux/err.h>
  32#include <linux/errno.h>
  33#include <linux/gpio/consumer.h>
  34#include <linux/i2c.h>
  35#include <linux/init.h>
  36#include <linux/interrupt.h>
  37#include <linux/io.h>
  38#include <linux/iopoll.h>
  39#include <linux/kernel.h>
  40#include <linux/spinlock.h>
  41#include <linux/hrtimer.h>
  42#include <linux/module.h>
  43#include <linux/of.h>
  44#include <linux/of_device.h>
  45#include <linux/of_dma.h>
  46#include <linux/pinctrl/consumer.h>
  47#include <linux/platform_data/i2c-imx.h>
  48#include <linux/platform_device.h>
  49#include <linux/pm_runtime.h>
  50#include <linux/sched.h>
  51#include <linux/slab.h>
  52
 
 
 
 
 
 
 
  53/* This will be the driver name the kernel reports */
  54#define DRIVER_NAME "imx-i2c"
  55
  56#define I2C_IMX_CHECK_DELAY 30000 /* Time to check for bus idle, in NS */
 
  57
  58/*
  59 * Enable DMA if transfer byte size is bigger than this threshold.
  60 * As the hardware request, it must bigger than 4 bytes.\
  61 * I have set '16' here, maybe it's not the best but I think it's
  62 * the appropriate.
  63 */
  64#define DMA_THRESHOLD	16
  65#define DMA_TIMEOUT	1000
  66
  67/* IMX I2C registers:
  68 * the I2C register offset is different between SoCs,
  69 * to provide support for all these chips, split the
  70 * register offset into a fixed base address and a
  71 * variable shift value, then the full register offset
  72 * will be calculated by
  73 * reg_off = ( reg_base_addr << reg_shift)
  74 */
  75#define IMX_I2C_IADR	0x00	/* i2c slave address */
  76#define IMX_I2C_IFDR	0x01	/* i2c frequency divider */
  77#define IMX_I2C_I2CR	0x02	/* i2c control */
  78#define IMX_I2C_I2SR	0x03	/* i2c status */
  79#define IMX_I2C_I2DR	0x04	/* i2c transfer data */
  80
  81/*
  82 * All of the layerscape series SoCs support IBIC register.
  83 */
  84#define IMX_I2C_IBIC	0x05    /* i2c bus interrupt config */
  85
  86#define IMX_I2C_REGSHIFT	2
  87#define VF610_I2C_REGSHIFT	0
  88
  89/* Bits of IMX I2C registers */
  90#define I2SR_RXAK	0x01
  91#define I2SR_IIF	0x02
  92#define I2SR_SRW	0x04
  93#define I2SR_IAL	0x10
  94#define I2SR_IBB	0x20
  95#define I2SR_IAAS	0x40
  96#define I2SR_ICF	0x80
  97#define I2CR_DMAEN	0x02
  98#define I2CR_RSTA	0x04
  99#define I2CR_TXAK	0x08
 100#define I2CR_MTX	0x10
 101#define I2CR_MSTA	0x20
 102#define I2CR_IIEN	0x40
 103#define I2CR_IEN	0x80
 104#define IBIC_BIIE	0x80 /* Bus idle interrupt enable */
 105
 106/* register bits different operating codes definition:
 107 * 1) I2SR: Interrupt flags clear operation differ between SoCs:
 108 * - write zero to clear(w0c) INT flag on i.MX,
 109 * - but write one to clear(w1c) INT flag on Vybrid.
 110 * 2) I2CR: I2C module enable operation also differ between SoCs:
 111 * - set I2CR_IEN bit enable the module on i.MX,
 112 * - but clear I2CR_IEN bit enable the module on Vybrid.
 113 */
 114#define I2SR_CLR_OPCODE_W0C	0x0
 115#define I2SR_CLR_OPCODE_W1C	(I2SR_IAL | I2SR_IIF)
 116#define I2CR_IEN_OPCODE_0	0x0
 117#define I2CR_IEN_OPCODE_1	I2CR_IEN
 118
 119#define I2C_PM_TIMEOUT		10 /* ms */
 120
 121/*
 122 * sorted list of clock divider, register value pairs
 123 * taken from table 26-5, p.26-9, Freescale i.MX
 124 * Integrated Portable System Processor Reference Manual
 125 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
 126 *
 127 * Duplicated divider values removed from list
 128 */
 129struct imx_i2c_clk_pair {
 130	u16	div;
 131	u16	val;
 132};
 133
 134static struct imx_i2c_clk_pair imx_i2c_clk_div[] = {
 135	{ 22,	0x20 }, { 24,	0x21 }, { 26,	0x22 }, { 28,	0x23 },
 136	{ 30,	0x00 },	{ 32,	0x24 }, { 36,	0x25 }, { 40,	0x26 },
 137	{ 42,	0x03 }, { 44,	0x27 },	{ 48,	0x28 }, { 52,	0x05 },
 138	{ 56,	0x29 }, { 60,	0x06 }, { 64,	0x2A },	{ 72,	0x2B },
 139	{ 80,	0x2C }, { 88,	0x09 }, { 96,	0x2D }, { 104,	0x0A },
 140	{ 112,	0x2E }, { 128,	0x2F }, { 144,	0x0C }, { 160,	0x30 },
 141	{ 192,	0x31 },	{ 224,	0x32 }, { 240,	0x0F }, { 256,	0x33 },
 142	{ 288,	0x10 }, { 320,	0x34 },	{ 384,	0x35 }, { 448,	0x36 },
 143	{ 480,	0x13 }, { 512,	0x37 }, { 576,	0x14 },	{ 640,	0x38 },
 144	{ 768,	0x39 }, { 896,	0x3A }, { 960,	0x17 }, { 1024,	0x3B },
 145	{ 1152,	0x18 }, { 1280,	0x3C }, { 1536,	0x3D }, { 1792,	0x3E },
 146	{ 1920,	0x1B },	{ 2048,	0x3F }, { 2304,	0x1C }, { 2560,	0x1D },
 147	{ 3072,	0x1E }, { 3840,	0x1F }
 148};
 149
 150/* Vybrid VF610 clock divider, register value pairs */
 151static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = {
 152	{ 20,   0x00 }, { 22,   0x01 }, { 24,   0x02 }, { 26,   0x03 },
 153	{ 28,   0x04 }, { 30,   0x05 }, { 32,   0x09 }, { 34,   0x06 },
 154	{ 36,   0x0A }, { 40,   0x07 }, { 44,   0x0C }, { 48,   0x0D },
 155	{ 52,   0x43 }, { 56,   0x0E }, { 60,   0x45 }, { 64,   0x12 },
 156	{ 68,   0x0F }, { 72,   0x13 }, { 80,   0x14 }, { 88,   0x15 },
 157	{ 96,   0x19 }, { 104,  0x16 }, { 112,  0x1A }, { 128,  0x17 },
 158	{ 136,  0x4F }, { 144,  0x1C }, { 160,  0x1D }, { 176,  0x55 },
 159	{ 192,  0x1E }, { 208,  0x56 }, { 224,  0x22 }, { 228,  0x24 },
 160	{ 240,  0x1F }, { 256,  0x23 }, { 288,  0x5C }, { 320,  0x25 },
 161	{ 384,  0x26 }, { 448,  0x2A }, { 480,  0x27 }, { 512,  0x2B },
 162	{ 576,  0x2C }, { 640,  0x2D }, { 768,  0x31 }, { 896,  0x32 },
 163	{ 960,  0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 },
 164	{ 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B },
 165	{ 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A },
 166	{ 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E },
 167};
 168
 169enum imx_i2c_type {
 170	IMX1_I2C,
 171	IMX21_I2C,
 172	VF610_I2C,
 173};
 174
 175struct imx_i2c_hwdata {
 176	enum imx_i2c_type	devtype;
 177	unsigned int		regshift;
 178	struct imx_i2c_clk_pair	*clk_div;
 179	unsigned int		ndivs;
 180	unsigned int		i2sr_clr_opcode;
 181	unsigned int		i2cr_ien_opcode;
 182	/*
 183	 * Errata ERR007805 or e7805:
 184	 * I2C: When the I2C clock speed is configured for 400 kHz,
 185	 * the SCL low period violates the I2C spec of 1.3 uS min.
 186	 */
 187	bool			has_err007805;
 188};
 189
 190struct imx_i2c_dma {
 191	struct dma_chan		*chan_tx;
 192	struct dma_chan		*chan_rx;
 193	struct dma_chan		*chan_using;
 194	struct completion	cmd_complete;
 195	dma_addr_t		dma_buf;
 196	unsigned int		dma_len;
 197	enum dma_transfer_direction dma_transfer_dir;
 198	enum dma_data_direction dma_data_dir;
 199};
 200
 201struct imx_i2c_struct {
 202	struct i2c_adapter	adapter;
 
 203	struct clk		*clk;
 204	struct notifier_block	clk_change_nb;
 205	void __iomem		*base;
 
 206	wait_queue_head_t	queue;
 207	unsigned long		i2csr;
 208	unsigned int		disable_delay;
 209	int			stopped;
 210	unsigned int		ifdr; /* IMX_I2C_IFDR */
 211	unsigned int		cur_clk;
 212	unsigned int		bitrate;
 213	const struct imx_i2c_hwdata	*hwdata;
 214	struct i2c_bus_recovery_info rinfo;
 215
 216	struct pinctrl *pinctrl;
 217	struct pinctrl_state *pinctrl_pins_default;
 218	struct pinctrl_state *pinctrl_pins_gpio;
 219
 220	struct imx_i2c_dma	*dma;
 221	struct i2c_client	*slave;
 222	enum i2c_slave_event last_slave_event;
 223
 224	/* For checking slave events. */
 225	spinlock_t     slave_lock;
 226	struct hrtimer slave_timer;
 227};
 228
 229static const struct imx_i2c_hwdata imx1_i2c_hwdata = {
 230	.devtype		= IMX1_I2C,
 231	.regshift		= IMX_I2C_REGSHIFT,
 232	.clk_div		= imx_i2c_clk_div,
 233	.ndivs			= ARRAY_SIZE(imx_i2c_clk_div),
 234	.i2sr_clr_opcode	= I2SR_CLR_OPCODE_W0C,
 235	.i2cr_ien_opcode	= I2CR_IEN_OPCODE_1,
 236
 237};
 238
 239static const struct imx_i2c_hwdata imx21_i2c_hwdata = {
 240	.devtype		= IMX21_I2C,
 241	.regshift		= IMX_I2C_REGSHIFT,
 242	.clk_div		= imx_i2c_clk_div,
 243	.ndivs			= ARRAY_SIZE(imx_i2c_clk_div),
 244	.i2sr_clr_opcode	= I2SR_CLR_OPCODE_W0C,
 245	.i2cr_ien_opcode	= I2CR_IEN_OPCODE_1,
 246
 247};
 248
 249static const struct imx_i2c_hwdata imx6_i2c_hwdata = {
 250	.devtype		= IMX21_I2C,
 251	.regshift		= IMX_I2C_REGSHIFT,
 252	.clk_div		= imx_i2c_clk_div,
 253	.ndivs			= ARRAY_SIZE(imx_i2c_clk_div),
 254	.i2sr_clr_opcode	= I2SR_CLR_OPCODE_W0C,
 255	.i2cr_ien_opcode	= I2CR_IEN_OPCODE_1,
 256	.has_err007805		= true,
 257};
 258
 259static struct imx_i2c_hwdata vf610_i2c_hwdata = {
 260	.devtype		= VF610_I2C,
 261	.regshift		= VF610_I2C_REGSHIFT,
 262	.clk_div		= vf610_i2c_clk_div,
 263	.ndivs			= ARRAY_SIZE(vf610_i2c_clk_div),
 264	.i2sr_clr_opcode	= I2SR_CLR_OPCODE_W1C,
 265	.i2cr_ien_opcode	= I2CR_IEN_OPCODE_0,
 266
 267};
 268
 269static const struct platform_device_id imx_i2c_devtype[] = {
 270	{
 271		.name = "imx1-i2c",
 272		.driver_data = (kernel_ulong_t)&imx1_i2c_hwdata,
 273	}, {
 274		.name = "imx21-i2c",
 275		.driver_data = (kernel_ulong_t)&imx21_i2c_hwdata,
 276	}, {
 277		/* sentinel */
 278	}
 279};
 280MODULE_DEVICE_TABLE(platform, imx_i2c_devtype);
 281
 282static const struct of_device_id i2c_imx_dt_ids[] = {
 283	{ .compatible = "fsl,imx1-i2c", .data = &imx1_i2c_hwdata, },
 284	{ .compatible = "fsl,imx21-i2c", .data = &imx21_i2c_hwdata, },
 285	{ .compatible = "fsl,imx6q-i2c", .data = &imx6_i2c_hwdata, },
 286	{ .compatible = "fsl,imx6sl-i2c", .data = &imx6_i2c_hwdata, },
 287	{ .compatible = "fsl,imx6sll-i2c", .data = &imx6_i2c_hwdata, },
 288	{ .compatible = "fsl,imx6sx-i2c", .data = &imx6_i2c_hwdata, },
 289	{ .compatible = "fsl,imx6ul-i2c", .data = &imx6_i2c_hwdata, },
 290	{ .compatible = "fsl,imx7s-i2c", .data = &imx6_i2c_hwdata, },
 291	{ .compatible = "fsl,imx8mm-i2c", .data = &imx6_i2c_hwdata, },
 292	{ .compatible = "fsl,imx8mn-i2c", .data = &imx6_i2c_hwdata, },
 293	{ .compatible = "fsl,imx8mp-i2c", .data = &imx6_i2c_hwdata, },
 294	{ .compatible = "fsl,imx8mq-i2c", .data = &imx6_i2c_hwdata, },
 295	{ .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, },
 296	{ /* sentinel */ }
 297};
 298MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids);
 299
 300static const struct acpi_device_id i2c_imx_acpi_ids[] = {
 301	{"NXP0001", .driver_data = (kernel_ulong_t)&vf610_i2c_hwdata},
 302	{ }
 303};
 304MODULE_DEVICE_TABLE(acpi, i2c_imx_acpi_ids);
 305
 306static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
 307{
 308	return i2c_imx->hwdata->devtype == IMX1_I2C;
 309}
 310
 311static inline int is_vf610_i2c(struct imx_i2c_struct *i2c_imx)
 312{
 313	return i2c_imx->hwdata->devtype == VF610_I2C;
 314}
 315
 316static inline void imx_i2c_write_reg(unsigned int val,
 317		struct imx_i2c_struct *i2c_imx, unsigned int reg)
 318{
 319	writeb(val, i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
 320}
 321
 322static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
 323		unsigned int reg)
 324{
 325	return readb(i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
 326}
 327
 328static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits)
 329{
 
 330	unsigned int temp;
 331
 332	/*
 333	 * i2sr_clr_opcode is the value to clear all interrupts. Here we want to
 334	 * clear only <bits>, so we write ~i2sr_clr_opcode with just <bits>
 335	 * toggled. This is required because i.MX needs W0C and Vybrid uses W1C.
 336	 */
 337	temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits;
 338	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
 339}
 340
 341/* Set up i2c controller register and i2c status register to default value. */
 342static void i2c_imx_reset_regs(struct imx_i2c_struct *i2c_imx)
 343{
 344	imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
 345			  i2c_imx, IMX_I2C_I2CR);
 346	i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
 347}
 348
 349/* Functions for DMA support */
 350static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
 351						dma_addr_t phy_addr)
 352{
 353	struct imx_i2c_dma *dma;
 354	struct dma_slave_config dma_sconfig;
 355	struct device *dev = &i2c_imx->adapter.dev;
 356	int ret;
 357
 358	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
 359	if (!dma)
 360		return;
 361
 362	dma->chan_tx = dma_request_chan(dev, "tx");
 363	if (IS_ERR(dma->chan_tx)) {
 364		ret = PTR_ERR(dma->chan_tx);
 365		if (ret != -ENODEV && ret != -EPROBE_DEFER)
 366			dev_err(dev, "can't request DMA tx channel (%d)\n", ret);
 367		goto fail_al;
 368	}
 369
 370	dma_sconfig.dst_addr = phy_addr +
 371				(IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
 372	dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 373	dma_sconfig.dst_maxburst = 1;
 374	dma_sconfig.direction = DMA_MEM_TO_DEV;
 375	ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig);
 376	if (ret < 0) {
 377		dev_err(dev, "can't configure tx channel (%d)\n", ret);
 378		goto fail_tx;
 379	}
 380
 381	dma->chan_rx = dma_request_chan(dev, "rx");
 382	if (IS_ERR(dma->chan_rx)) {
 383		ret = PTR_ERR(dma->chan_rx);
 384		if (ret != -ENODEV && ret != -EPROBE_DEFER)
 385			dev_err(dev, "can't request DMA rx channel (%d)\n", ret);
 386		goto fail_tx;
 387	}
 388
 389	dma_sconfig.src_addr = phy_addr +
 390				(IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
 391	dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 392	dma_sconfig.src_maxburst = 1;
 393	dma_sconfig.direction = DMA_DEV_TO_MEM;
 394	ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig);
 395	if (ret < 0) {
 396		dev_err(dev, "can't configure rx channel (%d)\n", ret);
 397		goto fail_rx;
 398	}
 399
 400	i2c_imx->dma = dma;
 401	init_completion(&dma->cmd_complete);
 402	dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
 403		dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
 404
 405	return;
 406
 407fail_rx:
 408	dma_release_channel(dma->chan_rx);
 409fail_tx:
 410	dma_release_channel(dma->chan_tx);
 411fail_al:
 412	devm_kfree(dev, dma);
 413}
 414
 415static void i2c_imx_dma_callback(void *arg)
 416{
 417	struct imx_i2c_struct *i2c_imx = (struct imx_i2c_struct *)arg;
 418	struct imx_i2c_dma *dma = i2c_imx->dma;
 419
 420	dma_unmap_single(dma->chan_using->device->dev, dma->dma_buf,
 421			dma->dma_len, dma->dma_data_dir);
 422	complete(&dma->cmd_complete);
 423}
 424
 425static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx,
 426					struct i2c_msg *msgs)
 427{
 428	struct imx_i2c_dma *dma = i2c_imx->dma;
 429	struct dma_async_tx_descriptor *txdesc;
 430	struct device *dev = &i2c_imx->adapter.dev;
 431	struct device *chan_dev = dma->chan_using->device->dev;
 432
 433	dma->dma_buf = dma_map_single(chan_dev, msgs->buf,
 434					dma->dma_len, dma->dma_data_dir);
 435	if (dma_mapping_error(chan_dev, dma->dma_buf)) {
 436		dev_err(dev, "DMA mapping failed\n");
 437		goto err_map;
 438	}
 439
 440	txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf,
 441					dma->dma_len, dma->dma_transfer_dir,
 442					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 443	if (!txdesc) {
 444		dev_err(dev, "Not able to get desc for DMA xfer\n");
 445		goto err_desc;
 446	}
 447
 448	reinit_completion(&dma->cmd_complete);
 449	txdesc->callback = i2c_imx_dma_callback;
 450	txdesc->callback_param = i2c_imx;
 451	if (dma_submit_error(dmaengine_submit(txdesc))) {
 452		dev_err(dev, "DMA submit failed\n");
 453		goto err_submit;
 454	}
 455
 456	dma_async_issue_pending(dma->chan_using);
 457	return 0;
 458
 459err_submit:
 460	dmaengine_terminate_sync(dma->chan_using);
 461err_desc:
 462	dma_unmap_single(chan_dev, dma->dma_buf,
 463			dma->dma_len, dma->dma_data_dir);
 464err_map:
 465	return -EINVAL;
 466}
 467
 468static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx)
 469{
 470	struct imx_i2c_dma *dma = i2c_imx->dma;
 471
 472	dma->dma_buf = 0;
 473	dma->dma_len = 0;
 474
 475	dma_release_channel(dma->chan_tx);
 476	dma->chan_tx = NULL;
 477
 478	dma_release_channel(dma->chan_rx);
 479	dma->chan_rx = NULL;
 480
 481	dma->chan_using = NULL;
 482}
 483
 484static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic)
 485{
 486	unsigned long orig_jiffies = jiffies;
 487	unsigned int temp;
 488
 489	while (1) {
 490		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 491
 492		/* check for arbitration lost */
 493		if (temp & I2SR_IAL) {
 494			i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
 495			return -EAGAIN;
 496		}
 497
 498		if (for_busy && (temp & I2SR_IBB)) {
 499			i2c_imx->stopped = 0;
 500			break;
 501		}
 502		if (!for_busy && !(temp & I2SR_IBB)) {
 503			i2c_imx->stopped = 1;
 504			break;
 
 
 
 
 505		}
 506		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 507			dev_dbg(&i2c_imx->adapter.dev,
 508				"<%s> I2C bus is busy\n", __func__);
 509			return -ETIMEDOUT;
 510		}
 511		if (atomic)
 512			udelay(100);
 513		else
 514			schedule();
 515	}
 516
 517	return 0;
 518}
 519
 520static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic)
 521{
 522	if (atomic) {
 523		void __iomem *addr = i2c_imx->base + (IMX_I2C_I2SR << i2c_imx->hwdata->regshift);
 524		unsigned int regval;
 525
 526		/*
 527		 * The formula for the poll timeout is documented in the RM
 528		 * Rev.5 on page 1878:
 529		 *     T_min = 10/F_scl
 530		 * Set the value hard as it is done for the non-atomic use-case.
 531		 * Use 10 kHz for the calculation since this is the minimum
 532		 * allowed SMBus frequency. Also add an offset of 100us since it
 533		 * turned out that the I2SR_IIF bit isn't set correctly within
 534		 * the minimum timeout in polling mode.
 535		 */
 536		readb_poll_timeout_atomic(addr, regval, regval & I2SR_IIF, 5, 1000 + 100);
 537		i2c_imx->i2csr = regval;
 538		i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
 539	} else {
 540		wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
 541	}
 542
 543	if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
 544		dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
 545		return -ETIMEDOUT;
 546	}
 547
 548	/* check for arbitration lost */
 549	if (i2c_imx->i2csr & I2SR_IAL) {
 550		dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__);
 551		i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
 552
 553		i2c_imx->i2csr = 0;
 554		return -EAGAIN;
 555	}
 556
 557	dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
 558	i2c_imx->i2csr = 0;
 559	return 0;
 560}
 561
 562static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
 563{
 564	if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
 565		dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
 566		return -ENXIO;  /* No ACK */
 567	}
 568
 569	dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
 570	return 0;
 571}
 572
 573static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
 574			    unsigned int i2c_clk_rate)
 575{
 576	struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div;
 577	unsigned int div;
 578	int i;
 579
 580	if (i2c_imx->hwdata->has_err007805 && i2c_imx->bitrate > 384000) {
 581		dev_dbg(&i2c_imx->adapter.dev,
 582			"SoC errata ERR007805 or e7805 applies, bus frequency limited from %d Hz to 384000 Hz.\n",
 583			i2c_imx->bitrate);
 584		i2c_imx->bitrate = 384000;
 585	}
 586
 587	/* Divider value calculation */
 588	if (i2c_imx->cur_clk == i2c_clk_rate)
 589		return;
 590
 591	i2c_imx->cur_clk = i2c_clk_rate;
 592
 593	div = DIV_ROUND_UP(i2c_clk_rate, i2c_imx->bitrate);
 594	if (div < i2c_clk_div[0].div)
 595		i = 0;
 596	else if (div > i2c_clk_div[i2c_imx->hwdata->ndivs - 1].div)
 597		i = i2c_imx->hwdata->ndivs - 1;
 598	else
 599		for (i = 0; i2c_clk_div[i].div < div; i++)
 600			;
 601
 602	/* Store divider value */
 603	i2c_imx->ifdr = i2c_clk_div[i].val;
 604
 605	/*
 606	 * There dummy delay is calculated.
 607	 * It should be about one I2C clock period long.
 608	 * This delay is used in I2C bus disable function
 609	 * to fix chip hardware bug.
 610	 */
 611	i2c_imx->disable_delay = DIV_ROUND_UP(500000U * i2c_clk_div[i].div,
 612					      i2c_clk_rate / 2);
 613
 614#ifdef CONFIG_I2C_DEBUG_BUS
 615	dev_dbg(&i2c_imx->adapter.dev, "I2C_CLK=%d, REQ DIV=%d\n",
 616		i2c_clk_rate, div);
 617	dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n",
 618		i2c_clk_div[i].val, i2c_clk_div[i].div);
 619#endif
 620}
 621
 622static int i2c_imx_clk_notifier_call(struct notifier_block *nb,
 623				     unsigned long action, void *data)
 624{
 625	struct clk_notifier_data *ndata = data;
 626	struct imx_i2c_struct *i2c_imx = container_of(nb,
 627						      struct imx_i2c_struct,
 628						      clk_change_nb);
 629
 630	if (action & POST_RATE_CHANGE)
 631		i2c_imx_set_clk(i2c_imx, ndata->new_rate);
 632
 633	return NOTIFY_OK;
 634}
 635
 636static int i2c_imx_start(struct imx_i2c_struct *i2c_imx, bool atomic)
 637{
 638	unsigned int temp = 0;
 639	int result;
 640
 641	imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR);
 
 
 
 642	/* Enable I2C controller */
 643	imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
 644	imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR);
 645
 646	/* Wait controller to be stable */
 647	if (atomic)
 648		udelay(50);
 649	else
 650		usleep_range(50, 150);
 651
 652	/* Start I2C transaction */
 653	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 654	temp |= I2CR_MSTA;
 655	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 656	result = i2c_imx_bus_busy(i2c_imx, 1, atomic);
 657	if (result)
 658		return result;
 
 659
 660	temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
 661	if (atomic)
 662		temp &= ~I2CR_IIEN; /* Disable interrupt */
 663
 664	temp &= ~I2CR_DMAEN;
 665	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 666	return result;
 667}
 668
 669static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx, bool atomic)
 670{
 671	unsigned int temp = 0;
 672
 673	if (!i2c_imx->stopped) {
 674		/* Stop I2C transaction */
 675		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 676		if (!(temp & I2CR_MSTA))
 677			i2c_imx->stopped = 1;
 678		temp &= ~(I2CR_MSTA | I2CR_MTX);
 679		if (i2c_imx->dma)
 680			temp &= ~I2CR_DMAEN;
 681		imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 682	}
 683	if (is_imx1_i2c(i2c_imx)) {
 684		/*
 685		 * This delay caused by an i.MXL hardware bug.
 686		 * If no (or too short) delay, no "STOP" bit will be generated.
 687		 */
 688		udelay(i2c_imx->disable_delay);
 689	}
 690
 691	if (!i2c_imx->stopped)
 692		i2c_imx_bus_busy(i2c_imx, 0, atomic);
 
 
 693
 694	/* Disable I2C controller */
 695	temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
 696	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 697}
 698
 699/*
 700 * Enable bus idle interrupts
 701 * Note: IBIC register will be cleared after disabled i2c module.
 702 * All of layerscape series SoCs support IBIC register.
 703 */
 704static void i2c_imx_enable_bus_idle(struct imx_i2c_struct *i2c_imx)
 705{
 706	if (is_vf610_i2c(i2c_imx)) {
 707		unsigned int temp;
 
 708
 709		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_IBIC);
 710		temp |= IBIC_BIIE;
 711		imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_IBIC);
 712	}
 713}
 
 
 
 
 714
 715static void i2c_imx_slave_event(struct imx_i2c_struct *i2c_imx,
 716				enum i2c_slave_event event, u8 *val)
 717{
 718	i2c_slave_event(i2c_imx->slave, event, val);
 719	i2c_imx->last_slave_event = event;
 720}
 721
 722static void i2c_imx_slave_finish_op(struct imx_i2c_struct *i2c_imx)
 723{
 724	u8 val = 0;
 725
 726	while (i2c_imx->last_slave_event != I2C_SLAVE_STOP) {
 727		switch (i2c_imx->last_slave_event) {
 728		case I2C_SLAVE_READ_REQUESTED:
 729			i2c_imx_slave_event(i2c_imx, I2C_SLAVE_READ_PROCESSED,
 730					    &val);
 731			break;
 732
 733		case I2C_SLAVE_WRITE_REQUESTED:
 734		case I2C_SLAVE_READ_PROCESSED:
 735		case I2C_SLAVE_WRITE_RECEIVED:
 736			i2c_imx_slave_event(i2c_imx, I2C_SLAVE_STOP, &val);
 737			break;
 738
 739		case I2C_SLAVE_STOP:
 740			break;
 741		}
 742	}
 743}
 744
 745/* Returns true if the timer should be restarted, false if not. */
 746static irqreturn_t i2c_imx_slave_handle(struct imx_i2c_struct *i2c_imx,
 747					unsigned int status, unsigned int ctl)
 748{
 749	u8 value = 0;
 750
 751	if (status & I2SR_IAL) { /* Arbitration lost */
 752		i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
 753		if (!(status & I2SR_IAAS))
 754			return IRQ_HANDLED;
 755	}
 756
 757	if (!(status & I2SR_IBB)) {
 758		/* No master on the bus, that could mean a stop condition. */
 759		i2c_imx_slave_finish_op(i2c_imx);
 760		return IRQ_HANDLED;
 761	}
 762
 763	if (!(status & I2SR_ICF))
 764		/* Data transfer still in progress, ignore this. */
 765		goto out;
 766
 767	if (status & I2SR_IAAS) { /* Addressed as a slave */
 768		i2c_imx_slave_finish_op(i2c_imx);
 769		if (status & I2SR_SRW) { /* Master wants to read from us*/
 770			dev_dbg(&i2c_imx->adapter.dev, "read requested");
 771			i2c_imx_slave_event(i2c_imx,
 772					    I2C_SLAVE_READ_REQUESTED, &value);
 773
 774			/* Slave transmit */
 775			ctl |= I2CR_MTX;
 776			imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
 777
 778			/* Send data */
 779			imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR);
 780		} else { /* Master wants to write to us */
 781			dev_dbg(&i2c_imx->adapter.dev, "write requested");
 782			i2c_imx_slave_event(i2c_imx,
 783					    I2C_SLAVE_WRITE_REQUESTED, &value);
 784
 785			/* Slave receive */
 786			ctl &= ~I2CR_MTX;
 787			imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
 788			/* Dummy read */
 789			imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 790		}
 791	} else if (!(ctl & I2CR_MTX)) { /* Receive mode */
 792		value = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 793		i2c_imx_slave_event(i2c_imx,
 794				    I2C_SLAVE_WRITE_RECEIVED, &value);
 795	} else if (!(status & I2SR_RXAK)) { /* Transmit mode received ACK */
 796		ctl |= I2CR_MTX;
 797		imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
 798
 799		i2c_imx_slave_event(i2c_imx,
 800				    I2C_SLAVE_READ_PROCESSED, &value);
 801
 802		imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR);
 803	} else { /* Transmit mode received NAK, operation is done */
 804		ctl &= ~I2CR_MTX;
 805		imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
 806		imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 807		i2c_imx_slave_finish_op(i2c_imx);
 808		return IRQ_HANDLED;
 809	}
 810
 811out:
 812	/*
 813	 * No need to check the return value here.  If it returns 0 or
 814	 * 1, then everything is fine.  If it returns -1, then the
 815	 * timer is running in the handler.  This will still work,
 816	 * though it may be redone (or already have been done) by the
 817	 * timer function.
 818	 */
 819	hrtimer_try_to_cancel(&i2c_imx->slave_timer);
 820	hrtimer_forward_now(&i2c_imx->slave_timer, I2C_IMX_CHECK_DELAY);
 821	hrtimer_restart(&i2c_imx->slave_timer);
 822	return IRQ_HANDLED;
 823}
 824
 825static enum hrtimer_restart i2c_imx_slave_timeout(struct hrtimer *t)
 826{
 827	struct imx_i2c_struct *i2c_imx = container_of(t, struct imx_i2c_struct,
 828						      slave_timer);
 829	unsigned int ctl, status;
 830	unsigned long flags;
 831
 832	spin_lock_irqsave(&i2c_imx->slave_lock, flags);
 833	status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 834	ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 835	i2c_imx_slave_handle(i2c_imx, status, ctl);
 836	spin_unlock_irqrestore(&i2c_imx->slave_lock, flags);
 837	return HRTIMER_NORESTART;
 838}
 839
 840static void i2c_imx_slave_init(struct imx_i2c_struct *i2c_imx)
 841{
 842	int temp;
 843
 844	/* Set slave addr. */
 845	imx_i2c_write_reg((i2c_imx->slave->addr << 1), i2c_imx, IMX_I2C_IADR);
 846
 847	i2c_imx_reset_regs(i2c_imx);
 848
 849	/* Enable module */
 850	temp = i2c_imx->hwdata->i2cr_ien_opcode;
 851	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 852
 853	/* Enable interrupt from i2c module */
 854	temp |= I2CR_IIEN;
 855	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 856
 857	i2c_imx_enable_bus_idle(i2c_imx);
 858}
 859
 860static int i2c_imx_reg_slave(struct i2c_client *client)
 861{
 862	struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter);
 863	int ret;
 864
 865	if (i2c_imx->slave)
 866		return -EBUSY;
 867
 868	i2c_imx->slave = client;
 869	i2c_imx->last_slave_event = I2C_SLAVE_STOP;
 870
 871	/* Resume */
 872	ret = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent);
 873	if (ret < 0) {
 874		dev_err(&i2c_imx->adapter.dev, "failed to resume i2c controller");
 875		return ret;
 876	}
 877
 878	i2c_imx_slave_init(i2c_imx);
 879
 880	return 0;
 881}
 882
 883static int i2c_imx_unreg_slave(struct i2c_client *client)
 884{
 885	struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter);
 886	int ret;
 887
 888	if (!i2c_imx->slave)
 889		return -EINVAL;
 890
 891	/* Reset slave address. */
 892	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
 893
 894	i2c_imx_reset_regs(i2c_imx);
 895
 896	i2c_imx->slave = NULL;
 897
 898	/* Suspend */
 899	ret = pm_runtime_put_sync(i2c_imx->adapter.dev.parent);
 900	if (ret < 0)
 901		dev_err(&i2c_imx->adapter.dev, "failed to suspend i2c controller");
 902
 903	return ret;
 904}
 905
 906static irqreturn_t i2c_imx_master_isr(struct imx_i2c_struct *i2c_imx, unsigned int status)
 907{
 908	/* save status register */
 909	i2c_imx->i2csr = status;
 910	wake_up(&i2c_imx->queue);
 911
 912	return IRQ_HANDLED;
 913}
 914
 915static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
 916{
 917	struct imx_i2c_struct *i2c_imx = dev_id;
 918	unsigned int ctl, status;
 919	unsigned long flags;
 920
 921	spin_lock_irqsave(&i2c_imx->slave_lock, flags);
 922	status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 923	ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 924
 925	if (status & I2SR_IIF) {
 926		i2c_imx_clear_irq(i2c_imx, I2SR_IIF);
 927		if (i2c_imx->slave) {
 928			if (!(ctl & I2CR_MSTA)) {
 929				irqreturn_t ret;
 930
 931				ret = i2c_imx_slave_handle(i2c_imx,
 932							   status, ctl);
 933				spin_unlock_irqrestore(&i2c_imx->slave_lock,
 934						       flags);
 935				return ret;
 936			}
 937			i2c_imx_slave_finish_op(i2c_imx);
 938		}
 939		spin_unlock_irqrestore(&i2c_imx->slave_lock, flags);
 940		return i2c_imx_master_isr(i2c_imx, status);
 941	}
 942	spin_unlock_irqrestore(&i2c_imx->slave_lock, flags);
 943
 944	return IRQ_NONE;
 945}
 946
 947static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx,
 948					struct i2c_msg *msgs)
 949{
 950	int result;
 951	unsigned long time_left;
 952	unsigned int temp = 0;
 953	unsigned long orig_jiffies = jiffies;
 954	struct imx_i2c_dma *dma = i2c_imx->dma;
 955	struct device *dev = &i2c_imx->adapter.dev;
 956
 957	dma->chan_using = dma->chan_tx;
 958	dma->dma_transfer_dir = DMA_MEM_TO_DEV;
 959	dma->dma_data_dir = DMA_TO_DEVICE;
 960	dma->dma_len = msgs->len - 1;
 961	result = i2c_imx_dma_xfer(i2c_imx, msgs);
 962	if (result)
 963		return result;
 964
 965	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 966	temp |= I2CR_DMAEN;
 967	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 968
 969	/*
 970	 * Write slave address.
 971	 * The first byte must be transmitted by the CPU.
 972	 */
 973	imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
 974	time_left = wait_for_completion_timeout(
 975				&i2c_imx->dma->cmd_complete,
 976				msecs_to_jiffies(DMA_TIMEOUT));
 977	if (time_left == 0) {
 978		dmaengine_terminate_sync(dma->chan_using);
 979		return -ETIMEDOUT;
 980	}
 981
 982	/* Waiting for transfer complete. */
 983	while (1) {
 984		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 985		if (temp & I2SR_ICF)
 986			break;
 987		if (time_after(jiffies, orig_jiffies +
 988				msecs_to_jiffies(DMA_TIMEOUT))) {
 989			dev_dbg(dev, "<%s> Timeout\n", __func__);
 990			return -ETIMEDOUT;
 991		}
 992		schedule();
 993	}
 994
 995	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 996	temp &= ~I2CR_DMAEN;
 997	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 998
 999	/* The last data byte must be transferred by the CPU. */
1000	imx_i2c_write_reg(msgs->buf[msgs->len-1],
1001				i2c_imx, IMX_I2C_I2DR);
1002	result = i2c_imx_trx_complete(i2c_imx, false);
1003	if (result)
1004		return result;
1005
1006	return i2c_imx_acked(i2c_imx);
1007}
1008
1009static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
1010			struct i2c_msg *msgs, bool is_lastmsg)
1011{
1012	int result;
1013	unsigned long time_left;
1014	unsigned int temp;
1015	unsigned long orig_jiffies = jiffies;
1016	struct imx_i2c_dma *dma = i2c_imx->dma;
1017	struct device *dev = &i2c_imx->adapter.dev;
1018
1019
1020	dma->chan_using = dma->chan_rx;
1021	dma->dma_transfer_dir = DMA_DEV_TO_MEM;
1022	dma->dma_data_dir = DMA_FROM_DEVICE;
1023	/* The last two data bytes must be transferred by the CPU. */
1024	dma->dma_len = msgs->len - 2;
1025	result = i2c_imx_dma_xfer(i2c_imx, msgs);
1026	if (result)
1027		return result;
1028
1029	time_left = wait_for_completion_timeout(
1030				&i2c_imx->dma->cmd_complete,
1031				msecs_to_jiffies(DMA_TIMEOUT));
1032	if (time_left == 0) {
1033		dmaengine_terminate_sync(dma->chan_using);
1034		return -ETIMEDOUT;
1035	}
1036
1037	/* waiting for transfer complete. */
1038	while (1) {
1039		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
1040		if (temp & I2SR_ICF)
1041			break;
1042		if (time_after(jiffies, orig_jiffies +
1043				msecs_to_jiffies(DMA_TIMEOUT))) {
1044			dev_dbg(dev, "<%s> Timeout\n", __func__);
1045			return -ETIMEDOUT;
1046		}
1047		schedule();
1048	}
1049
1050	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1051	temp &= ~I2CR_DMAEN;
1052	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1053
1054	/* read n-1 byte data */
1055	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1056	temp |= I2CR_TXAK;
1057	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1058
1059	msgs->buf[msgs->len-2] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1060	/* read n byte data */
1061	result = i2c_imx_trx_complete(i2c_imx, false);
1062	if (result)
1063		return result;
1064
1065	if (is_lastmsg) {
1066		/*
1067		 * It must generate STOP before read I2DR to prevent
1068		 * controller from generating another clock cycle
1069		 */
1070		dev_dbg(dev, "<%s> clear MSTA\n", __func__);
1071		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1072		if (!(temp & I2CR_MSTA))
1073			i2c_imx->stopped = 1;
1074		temp &= ~(I2CR_MSTA | I2CR_MTX);
1075		imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1076		if (!i2c_imx->stopped)
1077			i2c_imx_bus_busy(i2c_imx, 0, false);
1078	} else {
1079		/*
1080		 * For i2c master receiver repeat restart operation like:
1081		 * read -> repeat MSTA -> read/write
1082		 * The controller must set MTX before read the last byte in
1083		 * the first read operation, otherwise the first read cost
1084		 * one extra clock cycle.
1085		 */
1086		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1087		temp |= I2CR_MTX;
1088		imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1089	}
1090	msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1091
1092	return 0;
1093}
1094
1095static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs,
1096			 bool atomic)
1097{
1098	int i, result;
1099
1100	dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
1101		__func__, i2c_8bit_addr_from_msg(msgs));
1102
1103	/* write slave address */
1104	imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
1105	result = i2c_imx_trx_complete(i2c_imx, atomic);
1106	if (result)
1107		return result;
1108	result = i2c_imx_acked(i2c_imx);
1109	if (result)
1110		return result;
1111	dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
1112
1113	/* write data */
1114	for (i = 0; i < msgs->len; i++) {
1115		dev_dbg(&i2c_imx->adapter.dev,
1116			"<%s> write byte: B%d=0x%X\n",
1117			__func__, i, msgs->buf[i]);
1118		imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR);
1119		result = i2c_imx_trx_complete(i2c_imx, atomic);
1120		if (result)
1121			return result;
1122		result = i2c_imx_acked(i2c_imx);
1123		if (result)
1124			return result;
1125	}
1126	return 0;
1127}
1128
1129static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs,
1130			bool is_lastmsg, bool atomic)
1131{
1132	int i, result;
1133	unsigned int temp;
1134	int block_data = msgs->flags & I2C_M_RECV_LEN;
1135	int use_dma = i2c_imx->dma && msgs->flags & I2C_M_DMA_SAFE &&
1136		msgs->len >= DMA_THRESHOLD && !block_data;
1137
1138	dev_dbg(&i2c_imx->adapter.dev,
1139		"<%s> write slave address: addr=0x%x\n",
1140		__func__, i2c_8bit_addr_from_msg(msgs));
1141
1142	/* write slave address */
1143	imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
1144	result = i2c_imx_trx_complete(i2c_imx, atomic);
1145	if (result)
1146		return result;
1147	result = i2c_imx_acked(i2c_imx);
1148	if (result)
1149		return result;
1150
1151	dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
1152
1153	/* setup bus to read data */
1154	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1155	temp &= ~I2CR_MTX;
1156
1157	/*
1158	 * Reset the I2CR_TXAK flag initially for SMBus block read since the
1159	 * length is unknown
1160	 */
1161	if ((msgs->len - 1) || block_data)
1162		temp &= ~I2CR_TXAK;
1163	if (use_dma)
1164		temp |= I2CR_DMAEN;
1165	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1166	imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */
1167
1168	dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
1169
1170	if (use_dma)
1171		return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg);
1172
1173	/* read data */
1174	for (i = 0; i < msgs->len; i++) {
1175		u8 len = 0;
1176
1177		result = i2c_imx_trx_complete(i2c_imx, atomic);
1178		if (result)
1179			return result;
1180		/*
1181		 * First byte is the length of remaining packet
1182		 * in the SMBus block data read. Add it to
1183		 * msgs->len.
1184		 */
1185		if ((!i) && block_data) {
1186			len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1187			if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX))
1188				return -EPROTO;
1189			dev_dbg(&i2c_imx->adapter.dev,
1190				"<%s> read length: 0x%X\n",
1191				__func__, len);
1192			msgs->len += len;
1193		}
1194		if (i == (msgs->len - 1)) {
1195			if (is_lastmsg) {
1196				/*
1197				 * It must generate STOP before read I2DR to prevent
1198				 * controller from generating another clock cycle
1199				 */
1200				dev_dbg(&i2c_imx->adapter.dev,
1201					"<%s> clear MSTA\n", __func__);
1202				temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1203				if (!(temp & I2CR_MSTA))
1204					i2c_imx->stopped =  1;
1205				temp &= ~(I2CR_MSTA | I2CR_MTX);
1206				imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1207				if (!i2c_imx->stopped)
1208					i2c_imx_bus_busy(i2c_imx, 0, atomic);
1209			} else {
1210				/*
1211				 * For i2c master receiver repeat restart operation like:
1212				 * read -> repeat MSTA -> read/write
1213				 * The controller must set MTX before read the last byte in
1214				 * the first read operation, otherwise the first read cost
1215				 * one extra clock cycle.
1216				 */
1217				temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1218				temp |= I2CR_MTX;
1219				imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1220			}
1221		} else if (i == (msgs->len - 2)) {
1222			dev_dbg(&i2c_imx->adapter.dev,
1223				"<%s> set TXAK\n", __func__);
1224			temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1225			temp |= I2CR_TXAK;
1226			imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1227		}
1228		if ((!i) && block_data)
1229			msgs->buf[0] = len;
1230		else
1231			msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1232		dev_dbg(&i2c_imx->adapter.dev,
1233			"<%s> read byte: B%d=0x%X\n",
1234			__func__, i, msgs->buf[i]);
1235	}
1236	return 0;
1237}
1238
1239static int i2c_imx_xfer_common(struct i2c_adapter *adapter,
1240			       struct i2c_msg *msgs, int num, bool atomic)
1241{
1242	unsigned int i, temp;
1243	int result;
1244	bool is_lastmsg = false;
1245	struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
1246
 
 
1247	/* Start I2C transfer */
1248	result = i2c_imx_start(i2c_imx, atomic);
1249	if (result) {
1250		/*
1251		 * Bus recovery uses gpiod_get_value_cansleep() which is not
1252		 * allowed within atomic context.
1253		 */
1254		if (!atomic && i2c_imx->adapter.bus_recovery_info) {
1255			i2c_recover_bus(&i2c_imx->adapter);
1256			result = i2c_imx_start(i2c_imx, atomic);
1257		}
1258	}
1259
1260	if (result)
1261		goto fail0;
1262
1263	/* read/write data */
1264	for (i = 0; i < num; i++) {
1265		if (i == num - 1)
1266			is_lastmsg = true;
1267
1268		if (i) {
1269			dev_dbg(&i2c_imx->adapter.dev,
1270				"<%s> repeated start\n", __func__);
1271			temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1272			temp |= I2CR_RSTA;
1273			imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1274			result = i2c_imx_bus_busy(i2c_imx, 1, atomic);
1275			if (result)
1276				goto fail0;
1277		}
1278		dev_dbg(&i2c_imx->adapter.dev,
1279			"<%s> transfer message: %d\n", __func__, i);
1280		/* write/read data */
1281#ifdef CONFIG_I2C_DEBUG_BUS
1282		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1283		dev_dbg(&i2c_imx->adapter.dev,
1284			"<%s> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
1285			__func__,
1286			(temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
1287			(temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
1288			(temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
1289		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
1290		dev_dbg(&i2c_imx->adapter.dev,
1291			"<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
1292			__func__,
1293			(temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
1294			(temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
1295			(temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
1296			(temp & I2SR_RXAK ? 1 : 0));
1297#endif
1298		if (msgs[i].flags & I2C_M_RD) {
1299			result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg, atomic);
1300		} else {
1301			if (!atomic &&
1302			    i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD &&
1303				msgs[i].flags & I2C_M_DMA_SAFE)
1304				result = i2c_imx_dma_write(i2c_imx, &msgs[i]);
1305			else
1306				result = i2c_imx_write(i2c_imx, &msgs[i], atomic);
1307		}
1308		if (result)
1309			goto fail0;
1310	}
1311
1312fail0:
1313	/* Stop I2C transfer */
1314	i2c_imx_stop(i2c_imx, atomic);
1315
1316	dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
1317		(result < 0) ? "error" : "success msg",
1318			(result < 0) ? result : num);
1319	/* After data is transferred, switch to slave mode(as a receiver) */
1320	if (i2c_imx->slave)
1321		i2c_imx_slave_init(i2c_imx);
1322
1323	return (result < 0) ? result : num;
1324}
1325
1326static int i2c_imx_xfer(struct i2c_adapter *adapter,
1327			struct i2c_msg *msgs, int num)
1328{
1329	struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
1330	int result;
1331
1332	result = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent);
1333	if (result < 0)
1334		return result;
1335
1336	result = i2c_imx_xfer_common(adapter, msgs, num, false);
1337
1338	pm_runtime_mark_last_busy(i2c_imx->adapter.dev.parent);
1339	pm_runtime_put_autosuspend(i2c_imx->adapter.dev.parent);
1340
1341	return result;
1342}
1343
1344static int i2c_imx_xfer_atomic(struct i2c_adapter *adapter,
1345			       struct i2c_msg *msgs, int num)
1346{
1347	struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
1348	int result;
1349
1350	result = clk_enable(i2c_imx->clk);
1351	if (result)
1352		return result;
1353
1354	result = i2c_imx_xfer_common(adapter, msgs, num, true);
1355
1356	clk_disable(i2c_imx->clk);
1357
1358	return result;
1359}
1360
1361static void i2c_imx_prepare_recovery(struct i2c_adapter *adap)
1362{
1363	struct imx_i2c_struct *i2c_imx;
 
 
 
 
 
 
1364
1365	i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
1366
1367	pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio);
1368}
 
 
 
 
 
 
 
 
1369
1370static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap)
1371{
1372	struct imx_i2c_struct *i2c_imx;
1373
1374	i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
 
 
 
 
1375
1376	pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default);
1377}
1378
1379/*
1380 * We switch SCL and SDA to their GPIO function and do some bitbanging
1381 * for bus recovery. These alternative pinmux settings can be
1382 * described in the device tree by a separate pinctrl state "gpio". If
1383 * this is missing this is not a big problem, the only implication is
1384 * that we can't do bus recovery.
1385 */
1386static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
1387		struct platform_device *pdev)
1388{
1389	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
1390
1391	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
1392	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
1393		dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
1394		return PTR_ERR(i2c_imx->pinctrl);
 
1395	}
1396
1397	i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
1398			PINCTRL_STATE_DEFAULT);
1399	i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
1400			"gpio");
1401	rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN);
1402	rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
1403
1404	if (PTR_ERR(rinfo->sda_gpiod) == -EPROBE_DEFER ||
1405	    PTR_ERR(rinfo->scl_gpiod) == -EPROBE_DEFER) {
1406		return -EPROBE_DEFER;
1407	} else if (IS_ERR(rinfo->sda_gpiod) ||
1408		   IS_ERR(rinfo->scl_gpiod) ||
1409		   IS_ERR(i2c_imx->pinctrl_pins_default) ||
1410		   IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
1411		dev_dbg(&pdev->dev, "recovery information incomplete\n");
1412		return 0;
1413	}
1414
1415	dev_dbg(&pdev->dev, "using scl%s for recovery\n",
1416		rinfo->sda_gpiod ? ",sda" : "");
1417
1418	rinfo->prepare_recovery = i2c_imx_prepare_recovery;
1419	rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
1420	rinfo->recover_bus = i2c_generic_scl_recovery;
1421	i2c_imx->adapter.bus_recovery_info = rinfo;
1422
1423	return 0;
1424}
1425
1426static u32 i2c_imx_func(struct i2c_adapter *adapter)
1427{
1428	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
1429		| I2C_FUNC_SMBUS_READ_BLOCK_DATA;
1430}
1431
1432static const struct i2c_algorithm i2c_imx_algo = {
1433	.master_xfer = i2c_imx_xfer,
1434	.master_xfer_atomic = i2c_imx_xfer_atomic,
1435	.functionality = i2c_imx_func,
1436	.reg_slave	= i2c_imx_reg_slave,
1437	.unreg_slave	= i2c_imx_unreg_slave,
1438};
1439
1440static int i2c_imx_probe(struct platform_device *pdev)
1441{
1442	struct imx_i2c_struct *i2c_imx;
1443	struct resource *res;
1444	struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
1445	void __iomem *base;
1446	int irq, ret;
1447	dma_addr_t phy_addr;
1448	const struct imx_i2c_hwdata *match;
1449
1450	irq = platform_get_irq(pdev, 0);
1451	if (irq < 0)
1452		return irq;
1453
1454	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1455	if (IS_ERR(base))
1456		return PTR_ERR(base);
1457
1458	phy_addr = (dma_addr_t)res->start;
1459	i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL);
1460	if (!i2c_imx)
1461		return -ENOMEM;
1462
1463	spin_lock_init(&i2c_imx->slave_lock);
1464	hrtimer_init(&i2c_imx->slave_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1465	i2c_imx->slave_timer.function = i2c_imx_slave_timeout;
1466
1467	match = device_get_match_data(&pdev->dev);
1468	if (match)
1469		i2c_imx->hwdata = match;
1470	else
1471		i2c_imx->hwdata = (struct imx_i2c_hwdata *)
1472				platform_get_device_id(pdev)->driver_data;
1473
1474	/* Setup i2c_imx driver structure */
1475	strscpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name));
1476	i2c_imx->adapter.owner		= THIS_MODULE;
1477	i2c_imx->adapter.algo		= &i2c_imx_algo;
1478	i2c_imx->adapter.dev.parent	= &pdev->dev;
1479	i2c_imx->adapter.nr		= pdev->id;
1480	i2c_imx->adapter.dev.of_node	= pdev->dev.of_node;
1481	i2c_imx->base			= base;
1482	ACPI_COMPANION_SET(&i2c_imx->adapter.dev, ACPI_COMPANION(&pdev->dev));
1483
1484	/* Get I2C clock */
1485	i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
1486	if (IS_ERR(i2c_imx->clk))
1487		return dev_err_probe(&pdev->dev, PTR_ERR(i2c_imx->clk),
1488				     "can't get I2C clock\n");
 
 
1489
1490	ret = clk_prepare_enable(i2c_imx->clk);
 
1491	if (ret) {
1492		dev_err(&pdev->dev, "can't enable I2C clock, ret=%d\n", ret);
1493		return ret;
1494	}
1495
1496	/* Init queue */
1497	init_waitqueue_head(&i2c_imx->queue);
1498
1499	/* Set up adapter data */
1500	i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
1501
1502	/* Set up platform driver data */
1503	platform_set_drvdata(pdev, i2c_imx);
 
 
 
1504
1505	pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
1506	pm_runtime_use_autosuspend(&pdev->dev);
1507	pm_runtime_set_active(&pdev->dev);
1508	pm_runtime_enable(&pdev->dev);
1509
1510	ret = pm_runtime_get_sync(&pdev->dev);
1511	if (ret < 0)
1512		goto rpm_disable;
1513
1514	/* Request IRQ */
1515	ret = request_threaded_irq(irq, i2c_imx_isr, NULL, IRQF_SHARED,
1516				   pdev->name, i2c_imx);
1517	if (ret) {
1518		dev_err(&pdev->dev, "can't claim irq %d\n", irq);
1519		goto rpm_disable;
1520	}
1521
1522	/* Set up clock divider */
1523	i2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
1524	ret = of_property_read_u32(pdev->dev.of_node,
1525				   "clock-frequency", &i2c_imx->bitrate);
1526	if (ret < 0 && pdata && pdata->bitrate)
1527		i2c_imx->bitrate = pdata->bitrate;
1528	i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call;
1529	clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb);
1530	i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk));
1531
1532	i2c_imx_reset_regs(i2c_imx);
1533
1534	/* Init optional bus recovery function */
1535	ret = i2c_imx_init_recovery_info(i2c_imx, pdev);
1536	/* Give it another chance if pinctrl used is not ready yet */
1537	if (ret == -EPROBE_DEFER)
1538		goto clk_notifier_unregister;
1539
1540	/* Add I2C adapter */
1541	ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
1542	if (ret < 0)
1543		goto clk_notifier_unregister;
 
 
1544
1545	pm_runtime_mark_last_busy(&pdev->dev);
1546	pm_runtime_put_autosuspend(&pdev->dev);
1547
1548	dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq);
1549	dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
 
 
 
1550	dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
1551		i2c_imx->adapter.name);
1552	dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
1553
1554	/* Init DMA config if supported */
1555	i2c_imx_dma_request(i2c_imx, phy_addr);
1556
1557	return 0;   /* Return OK */
1558
1559clk_notifier_unregister:
1560	clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
1561	free_irq(irq, i2c_imx);
1562rpm_disable:
1563	pm_runtime_put_noidle(&pdev->dev);
1564	pm_runtime_disable(&pdev->dev);
1565	pm_runtime_set_suspended(&pdev->dev);
1566	pm_runtime_dont_use_autosuspend(&pdev->dev);
1567	clk_disable_unprepare(i2c_imx->clk);
1568	return ret;
 
 
 
 
1569}
1570
1571static int i2c_imx_remove(struct platform_device *pdev)
1572{
1573	struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
1574	int irq, ret;
1575
1576	ret = pm_runtime_get_sync(&pdev->dev);
1577
1578	hrtimer_cancel(&i2c_imx->slave_timer);
1579
1580	/* remove adapter */
1581	dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
1582	i2c_del_adapter(&i2c_imx->adapter);
 
1583
1584	if (i2c_imx->dma)
1585		i2c_imx_dma_free(i2c_imx);
1586
1587	if (ret >= 0) {
1588		/* setup chip registers to defaults */
1589		imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
1590		imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR);
1591		imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
1592		imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
1593		clk_disable(i2c_imx->clk);
1594	}
1595
1596	clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
1597	irq = platform_get_irq(pdev, 0);
1598	if (irq >= 0)
1599		free_irq(irq, i2c_imx);
1600
1601	clk_unprepare(i2c_imx->clk);
1602
1603	pm_runtime_put_noidle(&pdev->dev);
1604	pm_runtime_disable(&pdev->dev);
1605
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1606	return 0;
1607}
1608
1609static int __maybe_unused i2c_imx_runtime_suspend(struct device *dev)
1610{
1611	struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
1612
1613	clk_disable(i2c_imx->clk);
1614
1615	return 0;
1616}
1617
1618static int __maybe_unused i2c_imx_runtime_resume(struct device *dev)
1619{
1620	struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
1621	int ret;
1622
1623	ret = clk_enable(i2c_imx->clk);
1624	if (ret)
1625		dev_err(dev, "can't enable I2C clock, ret=%d\n", ret);
1626
1627	return ret;
1628}
1629
1630static const struct dev_pm_ops i2c_imx_pm_ops = {
1631	SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend,
1632			   i2c_imx_runtime_resume, NULL)
1633};
1634
1635static struct platform_driver i2c_imx_driver = {
1636	.probe = i2c_imx_probe,
1637	.remove = i2c_imx_remove,
1638	.driver = {
1639		.name = DRIVER_NAME,
1640		.pm = &i2c_imx_pm_ops,
1641		.of_match_table = i2c_imx_dt_ids,
1642		.acpi_match_table = i2c_imx_acpi_ids,
1643	},
1644	.id_table = imx_i2c_devtype,
1645};
1646
1647static int __init i2c_adap_imx_init(void)
1648{
1649	return platform_driver_register(&i2c_imx_driver);
1650}
1651subsys_initcall(i2c_adap_imx_init);
1652
1653static void __exit i2c_adap_imx_exit(void)
1654{
1655	platform_driver_unregister(&i2c_imx_driver);
1656}
1657module_exit(i2c_adap_imx_exit);
1658
1659MODULE_LICENSE("GPL");
1660MODULE_AUTHOR("Darius Augulis");
1661MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
1662MODULE_ALIAS("platform:" DRIVER_NAME);