/drivers/i2c/busses/i2c-eg20t.c

  1/*
  2 * Copyright (C) 2010 OKI SEMICONDUCTOR CO., LTD.
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License as published by
  6 * the Free Software Foundation; version 2 of the License.
  7 *
  8 * This program is distributed in the hope that it will be useful,
  9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 11 * GNU General Public License for more details.
 12 *
 13 * You should have received a copy of the GNU General Public License
 14 * along with this program; if not, write to the Free Software
 15 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 16 */
 17
 18#include <linux/module.h>
 19#include <linux/kernel.h>
 20#include <linux/delay.h>
 21#include <linux/init.h>
 22#include <linux/errno.h>
 23#include <linux/i2c.h>
 24#include <linux/fs.h>
 25#include <linux/io.h>
 26#include <linux/types.h>
 27#include <linux/interrupt.h>
 28#include <linux/jiffies.h>
 29#include <linux/pci.h>
 30#include <linux/mutex.h>
 31#include <linux/ktime.h>
 32#include <linux/slab.h>
 33
 34#define PCH_EVENT_SET	0	/* I2C Interrupt Event Set Status */
 35#define PCH_EVENT_NONE	1	/* I2C Interrupt Event Clear Status */
 36#define PCH_MAX_CLK		100000	/* Maximum Clock speed in MHz */
 37#define PCH_BUFFER_MODE_ENABLE	0x0002	/* flag for Buffer mode enable */
 38#define PCH_EEPROM_SW_RST_MODE_ENABLE	0x0008	/* EEPROM SW RST enable flag */
 39
 40#define PCH_I2CSADR	0x00	/* I2C slave address register */
 41#define PCH_I2CCTL	0x04	/* I2C control register */
 42#define PCH_I2CSR	0x08	/* I2C status register */
 43#define PCH_I2CDR	0x0C	/* I2C data register */
 44#define PCH_I2CMON	0x10	/* I2C bus monitor register */
 45#define PCH_I2CBC	0x14	/* I2C bus transfer rate setup counter */
 46#define PCH_I2CMOD	0x18	/* I2C mode register */
 47#define PCH_I2CBUFSLV	0x1C	/* I2C buffer mode slave address register */
 48#define PCH_I2CBUFSUB	0x20	/* I2C buffer mode subaddress register */
 49#define PCH_I2CBUFFOR	0x24	/* I2C buffer mode format register */
 50#define PCH_I2CBUFCTL	0x28	/* I2C buffer mode control register */
 51#define PCH_I2CBUFMSK	0x2C	/* I2C buffer mode interrupt mask register */
 52#define PCH_I2CBUFSTA	0x30	/* I2C buffer mode status register */
 53#define PCH_I2CBUFLEV	0x34	/* I2C buffer mode level register */
 54#define PCH_I2CESRFOR	0x38	/* EEPROM software reset mode format register */
 55#define PCH_I2CESRCTL	0x3C	/* EEPROM software reset mode ctrl register */
 56#define PCH_I2CESRMSK	0x40	/* EEPROM software reset mode */
 57#define PCH_I2CESRSTA	0x44	/* EEPROM software reset mode status register */
 58#define PCH_I2CTMR	0x48	/* I2C timer register */
 59#define PCH_I2CSRST	0xFC	/* I2C reset register */
 60#define PCH_I2CNF	0xF8	/* I2C noise filter register */
 61
 62#define BUS_IDLE_TIMEOUT	20
 63#define PCH_I2CCTL_I2CMEN	0x0080
 64#define TEN_BIT_ADDR_DEFAULT	0xF000
 65#define TEN_BIT_ADDR_MASK	0xF0
 66#define PCH_START		0x0020
 67#define PCH_ESR_START		0x0001
 68#define PCH_BUFF_START		0x1
 69#define PCH_REPSTART		0x0004
 70#define PCH_ACK			0x0008
 71#define PCH_GETACK		0x0001
 72#define CLR_REG			0x0
 73#define I2C_RD			0x1
 74#define I2CMCF_BIT		0x0080
 75#define I2CMIF_BIT		0x0002
 76#define I2CMAL_BIT		0x0010
 77#define I2CBMFI_BIT		0x0001
 78#define I2CBMAL_BIT		0x0002
 79#define I2CBMNA_BIT		0x0004
 80#define I2CBMTO_BIT		0x0008
 81#define I2CBMIS_BIT		0x0010
 82#define I2CESRFI_BIT		0X0001
 83#define I2CESRTO_BIT		0x0002
 84#define I2CESRFIIE_BIT		0x1
 85#define I2CESRTOIE_BIT		0x2
 86#define I2CBMDZ_BIT		0x0040
 87#define I2CBMAG_BIT		0x0020
 88#define I2CMBB_BIT		0x0020
 89#define BUFFER_MODE_MASK	(I2CBMFI_BIT | I2CBMAL_BIT | I2CBMNA_BIT | \
 90				I2CBMTO_BIT | I2CBMIS_BIT)
 91#define I2C_ADDR_MSK		0xFF
 92#define I2C_MSB_2B_MSK		0x300
 93#define FAST_MODE_CLK		400
 94#define FAST_MODE_EN		0x0001
 95#define SUB_ADDR_LEN_MAX	4
 96#define BUF_LEN_MAX		32
 97#define PCH_BUFFER_MODE		0x1
 98#define EEPROM_SW_RST_MODE	0x0002
 99#define NORMAL_INTR_ENBL	0x0300
100#define EEPROM_RST_INTR_ENBL	(I2CESRFIIE_BIT | I2CESRTOIE_BIT)
101#define EEPROM_RST_INTR_DISBL	0x0
102#define BUFFER_MODE_INTR_ENBL	0x001F
103#define BUFFER_MODE_INTR_DISBL	0x0
104#define NORMAL_MODE		0x0
105#define BUFFER_MODE		0x1
106#define EEPROM_SR_MODE		0x2
107#define I2C_TX_MODE		0x0010
108#define PCH_BUF_TX		0xFFF7
109#define PCH_BUF_RD		0x0008
110#define I2C_ERROR_MASK	(I2CESRTO_EVENT | I2CBMIS_EVENT | I2CBMTO_EVENT | \
111			I2CBMNA_EVENT | I2CBMAL_EVENT | I2CMAL_EVENT)
112#define I2CMAL_EVENT		0x0001
113#define I2CMCF_EVENT		0x0002
114#define I2CBMFI_EVENT		0x0004
115#define I2CBMAL_EVENT		0x0008
116#define I2CBMNA_EVENT		0x0010
117#define I2CBMTO_EVENT		0x0020
118#define I2CBMIS_EVENT		0x0040
119#define I2CESRFI_EVENT		0x0080
120#define I2CESRTO_EVENT		0x0100
121#define PCI_DEVICE_ID_PCH_I2C	0x8817
122
123#define pch_dbg(adap, fmt, arg...)  \
124	dev_dbg(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
125
126#define pch_err(adap, fmt, arg...)  \
127	dev_err(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
128
129#define pch_pci_err(pdev, fmt, arg...)  \
130	dev_err(&pdev->dev, "%s :" fmt, __func__, ##arg)
131
132#define pch_pci_dbg(pdev, fmt, arg...)  \
133	dev_dbg(&pdev->dev, "%s :" fmt, __func__, ##arg)
134
135/*
136Set the number of I2C instance max
137Intel EG20T PCH :		1ch
138OKI SEMICONDUCTOR ML7213 IOH :	2ch
139*/
140#define PCH_I2C_MAX_DEV			2
141
142/**
143 * struct i2c_algo_pch_data - for I2C driver functionalities
144 * @pch_adapter:		stores the reference to i2c_adapter structure
145 * @p_adapter_info:		stores the reference to adapter_info structure
146 * @pch_base_address:		specifies the remapped base address
147 * @pch_buff_mode_en:		specifies if buffer mode is enabled
148 * @pch_event_flag:		specifies occurrence of interrupt events
149 * @pch_i2c_xfer_in_progress:	specifies whether the transfer is completed
150 */
151struct i2c_algo_pch_data {
152	struct i2c_adapter pch_adapter;
153	struct adapter_info *p_adapter_info;
154	void __iomem *pch_base_address;
155	int pch_buff_mode_en;
156	u32 pch_event_flag;
157	bool pch_i2c_xfer_in_progress;
158};
159
160/**
161 * struct adapter_info - This structure holds the adapter information for the
162			 PCH i2c controller
163 * @pch_data:		stores a list of i2c_algo_pch_data
164 * @pch_i2c_suspended:	specifies whether the system is suspended or not
165 *			perhaps with more lines and words.
166 * @ch_num:		specifies the number of i2c instance
167 *
168 * pch_data has as many elements as maximum I2C channels
169 */
170struct adapter_info {
171	struct i2c_algo_pch_data pch_data[PCH_I2C_MAX_DEV];
172	bool pch_i2c_suspended;
173	int ch_num;
174};
175
176
177static int pch_i2c_speed = 100; /* I2C bus speed in Kbps */
178static int pch_clk = 50000;	/* specifies I2C clock speed in KHz */
179static wait_queue_head_t pch_event;
180static DEFINE_MUTEX(pch_mutex);
181
182/* Definition for ML7213 by OKI SEMICONDUCTOR */
183#define PCI_VENDOR_ID_ROHM		0x10DB
184#define PCI_DEVICE_ID_ML7213_I2C	0x802D
185#define PCI_DEVICE_ID_ML7223_I2C	0x8010
186
187static struct pci_device_id __devinitdata pch_pcidev_id[] = {
188	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_I2C),   1, },
189	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_I2C), 2, },
190	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_I2C), 1, },
191	{0,}
192};
193
194static irqreturn_t pch_i2c_handler(int irq, void *pData);
195
196static inline void pch_setbit(void __iomem *addr, u32 offset, u32 bitmask)
197{
198	u32 val;
199	val = ioread32(addr + offset);
200	val |= bitmask;
201	iowrite32(val, addr + offset);
202}
203
204static inline void pch_clrbit(void __iomem *addr, u32 offset, u32 bitmask)
205{
206	u32 val;
207	val = ioread32(addr + offset);
208	val &= (~bitmask);
209	iowrite32(val, addr + offset);
210}
211
212/**
213 * pch_i2c_init() - hardware initialization of I2C module
214 * @adap:	Pointer to struct i2c_algo_pch_data.
215 */
216static void pch_i2c_init(struct i2c_algo_pch_data *adap)
217{
218	void __iomem *p = adap->pch_base_address;
219	u32 pch_i2cbc;
220	u32 pch_i2ctmr;
221	u32 reg_value;
222
223	/* reset I2C controller */
224	iowrite32(0x01, p + PCH_I2CSRST);
225	msleep(20);
226	iowrite32(0x0, p + PCH_I2CSRST);
227
228	/* Initialize I2C registers */
229	iowrite32(0x21, p + PCH_I2CNF);
230
231	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_I2CCTL_I2CMEN);
232
233	if (pch_i2c_speed != 400)
234		pch_i2c_speed = 100;
235
236	reg_value = PCH_I2CCTL_I2CMEN;
237	if (pch_i2c_speed == FAST_MODE_CLK) {
238		reg_value |= FAST_MODE_EN;
239		pch_dbg(adap, "Fast mode enabled\n");
240	}
241
242	if (pch_clk > PCH_MAX_CLK)
243		pch_clk = 62500;
244
245	pch_i2cbc = (pch_clk + (pch_i2c_speed * 4)) / (pch_i2c_speed * 8);
246	/* Set transfer speed in I2CBC */
247	iowrite32(pch_i2cbc, p + PCH_I2CBC);
248
249	pch_i2ctmr = (pch_clk) / 8;
250	iowrite32(pch_i2ctmr, p + PCH_I2CTMR);
251
252	reg_value |= NORMAL_INTR_ENBL;	/* Enable interrupts in normal mode */
253	iowrite32(reg_value, p + PCH_I2CCTL);
254
255	pch_dbg(adap,
256		"I2CCTL=%x pch_i2cbc=%x pch_i2ctmr=%x Enable interrupts\n",
257		ioread32(p + PCH_I2CCTL), pch_i2cbc, pch_i2ctmr);
258
259	init_waitqueue_head(&pch_event);
260}
261
262static inline bool ktime_lt(const ktime_t cmp1, const ktime_t cmp2)
263{
264	return cmp1.tv64 < cmp2.tv64;
265}
266
267/**
268 * pch_i2c_wait_for_bus_idle() - check the status of bus.
269 * @adap:	Pointer to struct i2c_algo_pch_data.
270 * @timeout:	waiting time counter (us).
271 */
272static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap,
273				     s32 timeout)
274{
275	void __iomem *p = adap->pch_base_address;
276
277	/* MAX timeout value is timeout*1000*1000nsec */
278	ktime_t ns_val = ktime_add_ns(ktime_get(), timeout*1000*1000);
279	do {
280		if ((ioread32(p + PCH_I2CSR) & I2CMBB_BIT) == 0)
281			break;
282		msleep(20);
283	} while (ktime_lt(ktime_get(), ns_val));
284
285	pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR));
286
287	if (timeout == 0) {
288		pch_err(adap, "%s: Timeout Error.return%d\n", __func__, -ETIME);
289		return -ETIME;
290	}
291
292	return 0;
293}
294
295/**
296 * pch_i2c_start() - Generate I2C start condition in normal mode.
297 * @adap:	Pointer to struct i2c_algo_pch_data.
298 *
299 * Generate I2C start condition in normal mode by setting I2CCTL.I2CMSTA to 1.
300 */
301static void pch_i2c_start(struct i2c_algo_pch_data *adap)
302{
303	void __iomem *p = adap->pch_base_address;
304	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
305	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
306}
307
308/**
309 * pch_i2c_wait_for_xfer_complete() - initiates a wait for the tx complete event
310 * @adap:	Pointer to struct i2c_algo_pch_data.
311 */
312static s32 pch_i2c_wait_for_xfer_complete(struct i2c_algo_pch_data *adap)
313{
314	s32 ret;
315	ret = wait_event_timeout(pch_event,
316			(adap->pch_event_flag != 0), msecs_to_jiffies(50));
317	if (ret < 0) {
318		pch_err(adap, "timeout: %x\n", adap->pch_event_flag);
319		return ret;
320	}
321
322	if (ret == 0) {
323		pch_err(adap, "timeout: %x\n", adap->pch_event_flag);
324		return -ETIMEDOUT;
325	}
326
327	if (adap->pch_event_flag & I2C_ERROR_MASK) {
328		pch_err(adap, "error bits set: %x\n", adap->pch_event_flag);
329		return -EIO;
330	}
331
332	adap->pch_event_flag = 0;
333
334	return 0;
335}
336
337/**
338 * pch_i2c_getack() - to confirm ACK/NACK
339 * @adap:	Pointer to struct i2c_algo_pch_data.
340 */
341static s32 pch_i2c_getack(struct i2c_algo_pch_data *adap)
342{
343	u32 reg_val;
344	void __iomem *p = adap->pch_base_address;
345	reg_val = ioread32(p + PCH_I2CSR) & PCH_GETACK;
346
347	if (reg_val != 0) {
348		pch_err(adap, "return%d\n", -EPROTO);
349		return -EPROTO;
350	}
351
352	return 0;
353}
354
355/**
356 * pch_i2c_stop() - generate stop condition in normal mode.
357 * @adap:	Pointer to struct i2c_algo_pch_data.
358 */
359static void pch_i2c_stop(struct i2c_algo_pch_data *adap)
360{
361	void __iomem *p = adap->pch_base_address;
362	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
363	/* clear the start bit */
364	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
365}
366
367/**
368 * pch_i2c_repstart() - generate repeated start condition in normal mode
369 * @adap:	Pointer to struct i2c_algo_pch_data.
370 */
371static void pch_i2c_repstart(struct i2c_algo_pch_data *adap)
372{
373	void __iomem *p = adap->pch_base_address;
374	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
375	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_REPSTART);
376}
377
378/**
379 * pch_i2c_writebytes() - write data to I2C bus in normal mode
380 * @i2c_adap:	Pointer to the struct i2c_adapter.
381 * @last:	specifies whether last message or not.
382 *		In the case of compound mode it will be 1 for last message,
383 *		otherwise 0.
384 * @first:	specifies whether first message or not.
385 *		1 for first message otherwise 0.
386 */
387static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
388			      struct i2c_msg *msgs, u32 last, u32 first)
389{
390	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
391	u8 *buf;
392	u32 length;
393	u32 addr;
394	u32 addr_2_msb;
395	u32 addr_8_lsb;
396	s32 wrcount;
397	void __iomem *p = adap->pch_base_address;
398
399	length = msgs->len;
400	buf = msgs->buf;
401	addr = msgs->addr;
402
403	/* enable master tx */
404	pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
405
406	pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL),
407		length);
408
409	if (first) {
410		if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
411			return -ETIME;
412	}
413
414	if (msgs->flags & I2C_M_TEN) {
415		addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7);
416		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
417		if (first)
418			pch_i2c_start(adap);
419		if (pch_i2c_wait_for_xfer_complete(adap) == 0 &&
420		    pch_i2c_getack(adap) == 0) {
421			addr_8_lsb = (addr & I2C_ADDR_MSK);
422			iowrite32(addr_8_lsb, p + PCH_I2CDR);
423		} else {
424			pch_i2c_stop(adap);
425			return -ETIME;
426		}
427	} else {
428		/* set 7 bit slave address and R/W bit as 0 */
429		iowrite32(addr << 1, p + PCH_I2CDR);
430		if (first)
431			pch_i2c_start(adap);
432	}
433
434	if ((pch_i2c_wait_for_xfer_complete(adap) == 0) &&
435	    (pch_i2c_getack(adap) == 0)) {
436		for (wrcount = 0; wrcount < length; ++wrcount) {
437			/* write buffer value to I2C data register */
438			iowrite32(buf[wrcount], p + PCH_I2CDR);
439			pch_dbg(adap, "writing %x to Data register\n",
440				buf[wrcount]);
441
442			if (pch_i2c_wait_for_xfer_complete(adap) != 0)
443				return -ETIME;
444
445			if (pch_i2c_getack(adap))
446				return -EIO;
447		}
448
449		/* check if this is the last message */
450		if (last)
451			pch_i2c_stop(adap);
452		else
453			pch_i2c_repstart(adap);
454	} else {
455		pch_i2c_stop(adap);
456		return -EIO;
457	}
458
459	pch_dbg(adap, "return=%d\n", wrcount);
460
461	return wrcount;
462}
463
464/**
465 * pch_i2c_sendack() - send ACK
466 * @adap:	Pointer to struct i2c_algo_pch_data.
467 */
468static void pch_i2c_sendack(struct i2c_algo_pch_data *adap)
469{
470	void __iomem *p = adap->pch_base_address;
471	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
472	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
473}
474
475/**
476 * pch_i2c_sendnack() - send NACK
477 * @adap:	Pointer to struct i2c_algo_pch_data.
478 */
479static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap)
480{
481	void __iomem *p = adap->pch_base_address;
482	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
483	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
484}
485
486/**
487 * pch_i2c_readbytes() - read data  from I2C bus in normal mode.
488 * @i2c_adap:	Pointer to the struct i2c_adapter.
489 * @msgs:	Pointer to i2c_msg structure.
490 * @last:	specifies whether last message or not.
491 * @first:	specifies whether first message or not.
492 */
493static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
494			     u32 last, u32 first)
495{
496	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
497
498	u8 *buf;
499	u32 count;
500	u32 length;
501	u32 addr;
502	u32 addr_2_msb;
503	void __iomem *p = adap->pch_base_address;
504
505	length = msgs->len;
506	buf = msgs->buf;
507	addr = msgs->addr;
508
509	/* enable master reception */
510	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
511
512	if (first) {
513		if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
514			return -ETIME;
515	}
516
517	if (msgs->flags & I2C_M_TEN) {
518		addr_2_msb = (((addr & I2C_MSB_2B_MSK) >> 7) | (I2C_RD));
519		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
520
521	} else {
522		/* 7 address bits + R/W bit */
523		addr = (((addr) << 1) | (I2C_RD));
524		iowrite32(addr, p + PCH_I2CDR);
525	}
526
527	/* check if it is the first message */
528	if (first)
529		pch_i2c_start(adap);
530
531	if ((pch_i2c_wait_for_xfer_complete(adap) == 0) &&
532	    (pch_i2c_getack(adap) == 0)) {
533		pch_dbg(adap, "return %d\n", 0);
534
535		if (length == 0) {
536			pch_i2c_stop(adap);
537			ioread32(p + PCH_I2CDR); /* Dummy read needs */
538
539			count = length;
540		} else {
541			int read_index;
542			int loop;
543			pch_i2c_sendack(adap);
544
545			/* Dummy read */
546			for (loop = 1, read_index = 0; loop < length; loop++) {
547				buf[read_index] = ioread32(p + PCH_I2CDR);
548
549				if (loop != 1)
550					read_index++;
551
552				if (pch_i2c_wait_for_xfer_complete(adap) != 0) {
553					pch_i2c_stop(adap);
554					return -ETIME;
555				}
556			}	/* end for */
557
558			pch_i2c_sendnack(adap);
559
560			buf[read_index] = ioread32(p + PCH_I2CDR);
561
562			if (length != 1)
563				read_index++;
564
565			if (pch_i2c_wait_for_xfer_complete(adap) == 0) {
566				if (last)
567					pch_i2c_stop(adap);
568				else
569					pch_i2c_repstart(adap);
570
571				buf[read_index++] = ioread32(p + PCH_I2CDR);
572				count = read_index;
573			} else {
574				count = -ETIME;
575			}
576
577		}
578	} else {
579		count = -ETIME;
580		pch_i2c_stop(adap);
581	}
582
583	return count;
584}
585
586/**
587 * pch_i2c_cb() - Interrupt handler Call back function
588 * @adap:	Pointer to struct i2c_algo_pch_data.
589 */
590static void pch_i2c_cb(struct i2c_algo_pch_data *adap)
591{
592	u32 sts;
593	void __iomem *p = adap->pch_base_address;
594
595	sts = ioread32(p + PCH_I2CSR);
596	sts &= (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT);
597	if (sts & I2CMAL_BIT)
598		adap->pch_event_flag |= I2CMAL_EVENT;
599
600	if (sts & I2CMCF_BIT)
601		adap->pch_event_flag |= I2CMCF_EVENT;
602
603	/* clear the applicable bits */
604	pch_clrbit(adap->pch_base_address, PCH_I2CSR, sts);
605
606	pch_dbg(adap, "PCH_I2CSR = %x\n", ioread32(p + PCH_I2CSR));
607
608	wake_up(&pch_event);
609}
610
611/**
612 * pch_i2c_handler() - interrupt handler for the PCH I2C controller
613 * @irq:	irq number.
614 * @pData:	cookie passed back to the handler function.
615 */
616static irqreturn_t pch_i2c_handler(int irq, void *pData)
617{
618	u32 reg_val;
619	int flag;
620	int i;
621	struct adapter_info *adap_info = pData;
622	void __iomem *p;
623	u32 mode;
624
625	for (i = 0, flag = 0; i < adap_info->ch_num; i++) {
626		p = adap_info->pch_data[i].pch_base_address;
627		mode = ioread32(p + PCH_I2CMOD);
628		mode &= BUFFER_MODE | EEPROM_SR_MODE;
629		if (mode != NORMAL_MODE) {
630			pch_err(adap_info->pch_data,
631				"I2C-%d mode(%d) is not supported\n", mode, i);
632			continue;
633		}
634		reg_val = ioread32(p + PCH_I2CSR);
635		if (reg_val & (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT)) {
636			pch_i2c_cb(&adap_info->pch_data[i]);
637			flag = 1;
638		}
639	}
640
641	return flag ? IRQ_HANDLED : IRQ_NONE;
642}
643
644/**
645 * pch_i2c_xfer() - Reading adnd writing data through I2C bus
646 * @i2c_adap:	Pointer to the struct i2c_adapter.
647 * @msgs:	Pointer to i2c_msg structure.
648 * @num:	number of messages.
649 */
650static s32 pch_i2c_xfer(struct i2c_adapter *i2c_adap,
651			struct i2c_msg *msgs, s32 num)
652{
653	struct i2c_msg *pmsg;
654	u32 i = 0;
655	u32 status;
656	u32 msglen;
657	u32 subaddrlen;
658	s32 ret;
659
660	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
661
662	ret = mutex_lock_interruptible(&pch_mutex);
663	if (ret)
664		return -ERESTARTSYS;
665
666	if (adap->p_adapter_info->pch_i2c_suspended) {
667		mutex_unlock(&pch_mutex);
668		return -EBUSY;
669	}
670
671	pch_dbg(adap, "adap->p_adapter_info->pch_i2c_suspended is %d\n",
672		adap->p_adapter_info->pch_i2c_suspended);
673	/* transfer not completed */
674	adap->pch_i2c_xfer_in_progress = true;
675
676	pmsg = &msgs[0];
677	pmsg->flags |= adap->pch_buff_mode_en;
678	status = pmsg->flags;
679	pch_dbg(adap,
680		"After invoking I2C_MODE_SEL :flag= 0x%x\n", status);
681	/* calculate sub address length and message length */
682	/* these are applicable only for buffer mode */
683	subaddrlen = pmsg->buf[0];
684	/* calculate actual message length excluding
685	 * the sub address fields */
686	msglen = (pmsg->len) - (subaddrlen + 1);
687	if (status & (I2C_M_RD)) {
688		pch_dbg(adap, "invoking pch_i2c_readbytes\n");
689		ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num),
690				   (i == 0));
691	} else {
692		pch_dbg(adap, "invoking pch_i2c_writebytes\n");
693		ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num),
694				    (i == 0));
695	}
696
697	adap->pch_i2c_xfer_in_progress = false;	/* transfer completed */
698
699	mutex_unlock(&pch_mutex);
700
701	return ret;
702}
703
704/**
705 * pch_i2c_func() - return the functionality of the I2C driver
706 * @adap:	Pointer to struct i2c_algo_pch_data.
707 */
708static u32 pch_i2c_func(struct i2c_adapter *adap)
709{
710	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
711}
712
713static struct i2c_algorithm pch_algorithm = {
714	.master_xfer = pch_i2c_xfer,
715	.functionality = pch_i2c_func
716};
717
718/**
719 * pch_i2c_disbl_int() - Disable PCH I2C interrupts
720 * @adap:	Pointer to struct i2c_algo_pch_data.
721 */
722static void pch_i2c_disbl_int(struct i2c_algo_pch_data *adap)
723{
724	void __iomem *p = adap->pch_base_address;
725
726	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, NORMAL_INTR_ENBL);
727
728	iowrite32(EEPROM_RST_INTR_DISBL, p + PCH_I2CESRMSK);
729
730	iowrite32(BUFFER_MODE_INTR_DISBL, p + PCH_I2CBUFMSK);
731}
732
733static int __devinit pch_i2c_probe(struct pci_dev *pdev,
734				   const struct pci_device_id *id)
735{
736	void __iomem *base_addr;
737	int ret;
738	int i, j;
739	struct adapter_info *adap_info;
740	struct i2c_adapter *pch_adap;
741
742	pch_pci_dbg(pdev, "Entered.\n");
743
744	adap_info = kzalloc((sizeof(struct adapter_info)), GFP_KERNEL);
745	if (adap_info == NULL) {
746		pch_pci_err(pdev, "Memory allocation FAILED\n");
747		return -ENOMEM;
748	}
749
750	ret = pci_enable_device(pdev);
751	if (ret) {
752		pch_pci_err(pdev, "pci_enable_device FAILED\n");
753		goto err_pci_enable;
754	}
755
756	ret = pci_request_regions(pdev, KBUILD_MODNAME);
757	if (ret) {
758		pch_pci_err(pdev, "pci_request_regions FAILED\n");
759		goto err_pci_req;
760	}
761
762	base_addr = pci_iomap(pdev, 1, 0);
763
764	if (base_addr == NULL) {
765		pch_pci_err(pdev, "pci_iomap FAILED\n");
766		ret = -ENOMEM;
767		goto err_pci_iomap;
768	}
769
770	/* Set the number of I2C channel instance */
771	adap_info->ch_num = id->driver_data;
772
773	for (i = 0; i < adap_info->ch_num; i++) {
774		pch_adap = &adap_info->pch_data[i].pch_adapter;
775		adap_info->pch_i2c_suspended = false;
776
777		adap_info->pch_data[i].p_adapter_info = adap_info;
778
779		pch_adap->owner = THIS_MODULE;
780		pch_adap->class = I2C_CLASS_HWMON;
781		strcpy(pch_adap->name, KBUILD_MODNAME);
782		pch_adap->algo = &pch_algorithm;
783		pch_adap->algo_data = &adap_info->pch_data[i];
784
785		/* base_addr + offset; */
786		adap_info->pch_data[i].pch_base_address = base_addr + 0x100 * i;
787
788		pch_adap->dev.parent = &pdev->dev;
789
790		ret = i2c_add_adapter(pch_adap);
791		if (ret) {
792			pch_pci_err(pdev, "i2c_add_adapter[ch:%d] FAILED\n", i);
793			goto err_i2c_add_adapter;
794		}
795
796		pch_i2c_init(&adap_info->pch_data[i]);
797	}
798	ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED,
799		  KBUILD_MODNAME, adap_info);
800	if (ret) {
801		pch_pci_err(pdev, "request_irq FAILED\n");
802		goto err_i2c_add_adapter;
803	}
804
805	pci_set_drvdata(pdev, adap_info);
806	pch_pci_dbg(pdev, "returns %d.\n", ret);
807	return 0;
808
809err_i2c_add_adapter:
810	for (j = 0; j < i; j++)
811		i2c_del_adapter(&adap_info->pch_data[j].pch_adapter);
812	pci_iounmap(pdev, base_addr);
813err_pci_iomap:
814	pci_release_regions(pdev);
815err_pci_req:
816	pci_disable_device(pdev);
817err_pci_enable:
818	kfree(adap_info);
819	return ret;
820}
821
822static void __devexit pch_i2c_remove(struct pci_dev *pdev)
823{
824	int i;
825	struct adapter_info *adap_info = pci_get_drvdata(pdev);
826
827	free_irq(pdev->irq, adap_info);
828
829	for (i = 0; i < adap_info->ch_num; i++) {
830		pch_i2c_disbl_int(&adap_info->pch_data[i]);
831		i2c_del_adapter(&adap_info->pch_data[i].pch_adapter);
832	}
833
834	if (adap_info->pch_data[0].pch_base_address)
835		pci_iounmap(pdev, adap_info->pch_data[0].pch_base_address);
836
837	for (i = 0; i < adap_info->ch_num; i++)
838		adap_info->pch_data[i].pch_base_address = 0;
839
840	pci_set_drvdata(pdev, NULL);
841
842	pci_release_regions(pdev);
843
844	pci_disable_device(pdev);
845	kfree(adap_info);
846}
847
848#ifdef CONFIG_PM
849static int pch_i2c_suspend(struct pci_dev *pdev, pm_message_t state)
850{
851	int ret;
852	int i;
853	struct adapter_info *adap_info = pci_get_drvdata(pdev);
854	void __iomem *p = adap_info->pch_data[0].pch_base_address;
855
856	adap_info->pch_i2c_suspended = true;
857
858	for (i = 0; i < adap_info->ch_num; i++) {
859		while ((adap_info->pch_data[i].pch_i2c_xfer_in_progress)) {
860			/* Wait until all channel transfers are completed */
861			msleep(20);
862		}
863	}
864
865	/* Disable the i2c interrupts */
866	for (i = 0; i < adap_info->ch_num; i++)
867		pch_i2c_disbl_int(&adap_info->pch_data[i]);
868
869	pch_pci_dbg(pdev, "I2CSR = %x I2CBUFSTA = %x I2CESRSTA = %x "
870		"invoked function pch_i2c_disbl_int successfully\n",
871		ioread32(p + PCH_I2CSR), ioread32(p + PCH_I2CBUFSTA),
872		ioread32(p + PCH_I2CESRSTA));
873
874	ret = pci_save_state(pdev);
875
876	if (ret) {
877		pch_pci_err(pdev, "pci_save_state\n");
878		return ret;
879	}
880
881	pci_enable_wake(pdev, PCI_D3hot, 0);
882	pci_disable_device(pdev);
883	pci_set_power_state(pdev, pci_choose_state(pdev, state));
884
885	return 0;
886}
887
888static int pch_i2c_resume(struct pci_dev *pdev)
889{
890	int i;
891	struct adapter_info *adap_info = pci_get_drvdata(pdev);
892
893	pci_set_power_state(pdev, PCI_D0);
894	pci_restore_state(pdev);
895
896	if (pci_enable_device(pdev) < 0) {
897		pch_pci_err(pdev, "pch_i2c_resume:pci_enable_device FAILED\n");
898		return -EIO;
899	}
900
901	pci_enable_wake(pdev, PCI_D3hot, 0);
902
903	for (i = 0; i < adap_info->ch_num; i++)
904		pch_i2c_init(&adap_info->pch_data[i]);
905
906	adap_info->pch_i2c_suspended = false;
907
908	return 0;
909}
910#else
911#define pch_i2c_suspend NULL
912#define pch_i2c_resume NULL
913#endif
914
915static struct pci_driver pch_pcidriver = {
916	.name = KBUILD_MODNAME,
917	.id_table = pch_pcidev_id,
918	.probe = pch_i2c_probe,
919	.remove = __devexit_p(pch_i2c_remove),
920	.suspend = pch_i2c_suspend,
921	.resume = pch_i2c_resume
922};
923
924static int __init pch_pci_init(void)
925{
926	return pci_register_driver(&pch_pcidriver);
927}
928module_init(pch_pci_init);
929
930static void __exit pch_pci_exit(void)
931{
932	pci_unregister_driver(&pch_pcidriver);
933}
934module_exit(pch_pci_exit);
935
936MODULE_DESCRIPTION("Intel EG20T PCH/OKI SEMICONDUCTOR ML7213 IOH I2C Driver");
937MODULE_LICENSE("GPL");
938MODULE_AUTHOR("Tomoya MORINAGA. <tomoya-linux@dsn.okisemi.com>");
939module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR));
940module_param(pch_clk, int, (S_IRUSR | S_IWUSR));