1/*
2 * Copyright (C) 2011 LAPIS 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
14#include <linux/module.h>
15#include <linux/kernel.h>
16#include <linux/delay.h>
17#include <linux/errno.h>
18#include <linux/i2c.h>
19#include <linux/fs.h>
20#include <linux/io.h>
21#include <linux/types.h>
22#include <linux/interrupt.h>
23#include <linux/jiffies.h>
24#include <linux/pci.h>
25#include <linux/mutex.h>
26#include <linux/ktime.h>
27#include <linux/slab.h>
28
29#define PCH_EVENT_SET	0	/* I2C Interrupt Event Set Status */
30#define PCH_EVENT_NONE	1	/* I2C Interrupt Event Clear Status */
31#define PCH_MAX_CLK		100000	/* Maximum Clock speed in MHz */
32#define PCH_BUFFER_MODE_ENABLE	0x0002	/* flag for Buffer mode enable */
33#define PCH_EEPROM_SW_RST_MODE_ENABLE	0x0008	/* EEPROM SW RST enable flag */
34
35#define PCH_I2CSADR	0x00	/* I2C slave address register */
36#define PCH_I2CCTL	0x04	/* I2C control register */
37#define PCH_I2CSR	0x08	/* I2C status register */
38#define PCH_I2CDR	0x0C	/* I2C data register */
39#define PCH_I2CMON	0x10	/* I2C bus monitor register */
40#define PCH_I2CBC	0x14	/* I2C bus transfer rate setup counter */
41#define PCH_I2CMOD	0x18	/* I2C mode register */
42#define PCH_I2CBUFSLV	0x1C	/* I2C buffer mode slave address register */
43#define PCH_I2CBUFSUB	0x20	/* I2C buffer mode subaddress register */
44#define PCH_I2CBUFFOR	0x24	/* I2C buffer mode format register */
45#define PCH_I2CBUFCTL	0x28	/* I2C buffer mode control register */
46#define PCH_I2CBUFMSK	0x2C	/* I2C buffer mode interrupt mask register */
47#define PCH_I2CBUFSTA	0x30	/* I2C buffer mode status register */
48#define PCH_I2CBUFLEV	0x34	/* I2C buffer mode level register */
49#define PCH_I2CESRFOR	0x38	/* EEPROM software reset mode format register */
50#define PCH_I2CESRCTL	0x3C	/* EEPROM software reset mode ctrl register */
51#define PCH_I2CESRMSK	0x40	/* EEPROM software reset mode */
52#define PCH_I2CESRSTA	0x44	/* EEPROM software reset mode status register */
53#define PCH_I2CTMR	0x48	/* I2C timer register */
54#define PCH_I2CSRST	0xFC	/* I2C reset register */
55#define PCH_I2CNF	0xF8	/* I2C noise filter register */
56
57#define BUS_IDLE_TIMEOUT	20
58#define PCH_I2CCTL_I2CMEN	0x0080
59#define TEN_BIT_ADDR_DEFAULT	0xF000
60#define TEN_BIT_ADDR_MASK	0xF0
61#define PCH_START		0x0020
62#define PCH_RESTART		0x0004
63#define PCH_ESR_START		0x0001
64#define PCH_BUFF_START		0x1
65#define PCH_REPSTART		0x0004
66#define PCH_ACK			0x0008
67#define PCH_GETACK		0x0001
68#define CLR_REG			0x0
69#define I2C_RD			0x1
70#define I2CMCF_BIT		0x0080
71#define I2CMIF_BIT		0x0002
72#define I2CMAL_BIT		0x0010
73#define I2CBMFI_BIT		0x0001
74#define I2CBMAL_BIT		0x0002
75#define I2CBMNA_BIT		0x0004
76#define I2CBMTO_BIT		0x0008
77#define I2CBMIS_BIT		0x0010
78#define I2CESRFI_BIT		0X0001
79#define I2CESRTO_BIT		0x0002
80#define I2CESRFIIE_BIT		0x1
81#define I2CESRTOIE_BIT		0x2
82#define I2CBMDZ_BIT		0x0040
83#define I2CBMAG_BIT		0x0020
84#define I2CMBB_BIT		0x0020
85#define BUFFER_MODE_MASK	(I2CBMFI_BIT | I2CBMAL_BIT | I2CBMNA_BIT | \
86				I2CBMTO_BIT | I2CBMIS_BIT)
87#define I2C_ADDR_MSK		0xFF
88#define I2C_MSB_2B_MSK		0x300
89#define FAST_MODE_CLK		400
90#define FAST_MODE_EN		0x0001
91#define SUB_ADDR_LEN_MAX	4
92#define BUF_LEN_MAX		32
93#define PCH_BUFFER_MODE		0x1
94#define EEPROM_SW_RST_MODE	0x0002
95#define NORMAL_INTR_ENBL	0x0300
96#define EEPROM_RST_INTR_ENBL	(I2CESRFIIE_BIT | I2CESRTOIE_BIT)
97#define EEPROM_RST_INTR_DISBL	0x0
98#define BUFFER_MODE_INTR_ENBL	0x001F
99#define BUFFER_MODE_INTR_DISBL	0x0
100#define NORMAL_MODE		0x0
101#define BUFFER_MODE		0x1
102#define EEPROM_SR_MODE		0x2
103#define I2C_TX_MODE		0x0010
104#define PCH_BUF_TX		0xFFF7
105#define PCH_BUF_RD		0x0008
106#define I2C_ERROR_MASK	(I2CESRTO_EVENT | I2CBMIS_EVENT | I2CBMTO_EVENT | \
107			I2CBMNA_EVENT | I2CBMAL_EVENT | I2CMAL_EVENT)
108#define I2CMAL_EVENT		0x0001
109#define I2CMCF_EVENT		0x0002
110#define I2CBMFI_EVENT		0x0004
111#define I2CBMAL_EVENT		0x0008
112#define I2CBMNA_EVENT		0x0010
113#define I2CBMTO_EVENT		0x0020
114#define I2CBMIS_EVENT		0x0040
115#define I2CESRFI_EVENT		0x0080
116#define I2CESRTO_EVENT		0x0100
117#define PCI_DEVICE_ID_PCH_I2C	0x8817
118
119#define pch_dbg(adap, fmt, arg...)  \
120	dev_dbg(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
121
122#define pch_err(adap, fmt, arg...)  \
123	dev_err(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
124
125#define pch_pci_err(pdev, fmt, arg...)  \
126	dev_err(&pdev->dev, "%s :" fmt, __func__, ##arg)
127
128#define pch_pci_dbg(pdev, fmt, arg...)  \
129	dev_dbg(&pdev->dev, "%s :" fmt, __func__, ##arg)
130
131/*
132Set the number of I2C instance max
133Intel EG20T PCH :		1ch
134LAPIS Semiconductor ML7213 IOH :	2ch
135LAPIS Semiconductor ML7831 IOH :	1ch
136*/
137#define PCH_I2C_MAX_DEV			2
138
139/**
140 * struct i2c_algo_pch_data - for I2C driver functionalities
141 * @pch_adapter:		stores the reference to i2c_adapter structure
142 * @p_adapter_info:		stores the reference to adapter_info structure
143 * @pch_base_address:		specifies the remapped base address
144 * @pch_buff_mode_en:		specifies if buffer mode is enabled
145 * @pch_event_flag:		specifies occurrence of interrupt events
146 * @pch_i2c_xfer_in_progress:	specifies whether the transfer is completed
147 */
148struct i2c_algo_pch_data {
149	struct i2c_adapter pch_adapter;
150	struct adapter_info *p_adapter_info;
151	void __iomem *pch_base_address;
152	int pch_buff_mode_en;
153	u32 pch_event_flag;
154	bool pch_i2c_xfer_in_progress;
155};
156
157/**
158 * struct adapter_info - This structure holds the adapter information for the
159			 PCH i2c controller
160 * @pch_data:		stores a list of i2c_algo_pch_data
161 * @pch_i2c_suspended:	specifies whether the system is suspended or not
162 *			perhaps with more lines and words.
163 * @ch_num:		specifies the number of i2c instance
164 *
165 * pch_data has as many elements as maximum I2C channels
166 */
167struct adapter_info {
168	struct i2c_algo_pch_data pch_data[PCH_I2C_MAX_DEV];
169	bool pch_i2c_suspended;
170	int ch_num;
171};
172
173
174static int pch_i2c_speed = 100; /* I2C bus speed in Kbps */
175static int pch_clk = 50000;	/* specifies I2C clock speed in KHz */
176static wait_queue_head_t pch_event;
177static DEFINE_MUTEX(pch_mutex);
178
179/* Definition for ML7213 by LAPIS Semiconductor */
180#define PCI_VENDOR_ID_ROHM		0x10DB
181#define PCI_DEVICE_ID_ML7213_I2C	0x802D
182#define PCI_DEVICE_ID_ML7223_I2C	0x8010
183#define PCI_DEVICE_ID_ML7831_I2C	0x8817
184
185static const struct pci_device_id pch_pcidev_id[] = {
186	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_I2C),   1, },
187	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_I2C), 2, },
188	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_I2C), 1, },
189	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_I2C), 1, },
190	{0,}
191};
192
193static irqreturn_t pch_i2c_handler(int irq, void *pData);
194
195static inline void pch_setbit(void __iomem *addr, u32 offset, u32 bitmask)
196{
197	u32 val;
198	val = ioread32(addr + offset);
199	val |= bitmask;
200	iowrite32(val, addr + offset);
201}
202
203static inline void pch_clrbit(void __iomem *addr, u32 offset, u32 bitmask)
204{
205	u32 val;
206	val = ioread32(addr + offset);
207	val &= (~bitmask);
208	iowrite32(val, addr + offset);
209}
210
211/**
212 * pch_i2c_init() - hardware initialization of I2C module
213 * @adap:	Pointer to struct i2c_algo_pch_data.
214 */
215static void pch_i2c_init(struct i2c_algo_pch_data *adap)
216{
217	void __iomem *p = adap->pch_base_address;
218	u32 pch_i2cbc;
219	u32 pch_i2ctmr;
220	u32 reg_value;
221
222	/* reset I2C controller */
223	iowrite32(0x01, p + PCH_I2CSRST);
224	msleep(20);
225	iowrite32(0x0, p + PCH_I2CSRST);
226
227	/* Initialize I2C registers */
228	iowrite32(0x21, p + PCH_I2CNF);
229
230	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_I2CCTL_I2CMEN);
231
232	if (pch_i2c_speed != 400)
233		pch_i2c_speed = 100;
234
235	reg_value = PCH_I2CCTL_I2CMEN;
236	if (pch_i2c_speed == FAST_MODE_CLK) {
237		reg_value |= FAST_MODE_EN;
238		pch_dbg(adap, "Fast mode enabled\n");
239	}
240
241	if (pch_clk > PCH_MAX_CLK)
242		pch_clk = 62500;
243
244	pch_i2cbc = (pch_clk + (pch_i2c_speed * 4)) / (pch_i2c_speed * 8);
245	/* Set transfer speed in I2CBC */
246	iowrite32(pch_i2cbc, p + PCH_I2CBC);
247
248	pch_i2ctmr = (pch_clk) / 8;
249	iowrite32(pch_i2ctmr, p + PCH_I2CTMR);
250
251	reg_value |= NORMAL_INTR_ENBL;	/* Enable interrupts in normal mode */
252	iowrite32(reg_value, p + PCH_I2CCTL);
253
254	pch_dbg(adap,
255		"I2CCTL=%x pch_i2cbc=%x pch_i2ctmr=%x Enable interrupts\n",
256		ioread32(p + PCH_I2CCTL), pch_i2cbc, pch_i2ctmr);
257
258	init_waitqueue_head(&pch_event);
259}
260
261/**
262 * pch_i2c_wait_for_bus_idle() - check the status of bus.
263 * @adap:	Pointer to struct i2c_algo_pch_data.
264 * @timeout:	waiting time counter (ms).
265 */
266static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap,
267				     s32 timeout)
268{
269	void __iomem *p = adap->pch_base_address;
270	int schedule = 0;
271	unsigned long end = jiffies + msecs_to_jiffies(timeout);
272
273	while (ioread32(p + PCH_I2CSR) & I2CMBB_BIT) {
274		if (time_after(jiffies, end)) {
275			pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR));
276			pch_err(adap, "%s: Timeout Error.return%d\n",
277					__func__, -ETIME);
278			pch_i2c_init(adap);
279
280			return -ETIME;
281		}
282
283		if (!schedule)
284			/* Retry after some usecs */
285			udelay(5);
286		else
287			/* Wait a bit more without consuming CPU */
288			usleep_range(20, 1000);
289
290		schedule = 1;
291	}
292
293	return 0;
294}
295
296/**
297 * pch_i2c_start() - Generate I2C start condition in normal mode.
298 * @adap:	Pointer to struct i2c_algo_pch_data.
299 *
300 * Generate I2C start condition in normal mode by setting I2CCTL.I2CMSTA to 1.
301 */
302static void pch_i2c_start(struct i2c_algo_pch_data *adap)
303{
304	void __iomem *p = adap->pch_base_address;
305	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
306	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
307}
308
309/**
310 * pch_i2c_stop() - generate stop condition in normal mode.
311 * @adap:	Pointer to struct i2c_algo_pch_data.
312 */
313static void pch_i2c_stop(struct i2c_algo_pch_data *adap)
314{
315	void __iomem *p = adap->pch_base_address;
316	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
317	/* clear the start bit */
318	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
319}
320
321static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap)
322{
323	long ret;
324	void __iomem *p = adap->pch_base_address;
325
326	ret = wait_event_timeout(pch_event,
327			(adap->pch_event_flag != 0), msecs_to_jiffies(1000));
328	if (!ret) {
329		pch_err(adap, "%s:wait-event timeout\n", __func__);
330		adap->pch_event_flag = 0;
331		pch_i2c_stop(adap);
332		pch_i2c_init(adap);
333		return -ETIMEDOUT;
334	}
335
336	if (adap->pch_event_flag & I2C_ERROR_MASK) {
337		pch_err(adap, "Lost Arbitration\n");
338		adap->pch_event_flag = 0;
339		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT);
340		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT);
341		pch_i2c_init(adap);
342		return -EAGAIN;
343	}
344
345	adap->pch_event_flag = 0;
346
347	if (ioread32(p + PCH_I2CSR) & PCH_GETACK) {
348		pch_dbg(adap, "Receive NACK for slave address setting\n");
349		return -ENXIO;
350	}
351
352	return 0;
353}
354
355/**
356 * pch_i2c_repstart() - generate repeated start condition in normal mode
357 * @adap:	Pointer to struct i2c_algo_pch_data.
358 */
359static void pch_i2c_repstart(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	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_REPSTART);
364}
365
366/**
367 * pch_i2c_writebytes() - write data to I2C bus in normal mode
368 * @i2c_adap:	Pointer to the struct i2c_adapter.
369 * @last:	specifies whether last message or not.
370 *		In the case of compound mode it will be 1 for last message,
371 *		otherwise 0.
372 * @first:	specifies whether first message or not.
373 *		1 for first message otherwise 0.
374 */
375static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
376			      struct i2c_msg *msgs, u32 last, u32 first)
377{
378	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
379	u8 *buf;
380	u32 length;
381	u32 addr;
382	u32 addr_2_msb;
383	u32 addr_8_lsb;
384	s32 wrcount;
385	s32 rtn;
386	void __iomem *p = adap->pch_base_address;
387
388	length = msgs->len;
389	buf = msgs->buf;
390	addr = msgs->addr;
391
392	/* enable master tx */
393	pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
394
395	pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL),
396		length);
397
398	if (first) {
399		if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
400			return -ETIME;
401	}
402
403	if (msgs->flags & I2C_M_TEN) {
404		addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7) & 0x06;
405		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
406		if (first)
407			pch_i2c_start(adap);
408
409		rtn = pch_i2c_wait_for_check_xfer(adap);
410		if (rtn)
411			return rtn;
412
413		addr_8_lsb = (addr & I2C_ADDR_MSK);
414		iowrite32(addr_8_lsb, p + PCH_I2CDR);
415	} else {
416		/* set 7 bit slave address and R/W bit as 0 */
417		iowrite32(addr << 1, p + PCH_I2CDR);
418		if (first)
419			pch_i2c_start(adap);
420	}
421
422	rtn = pch_i2c_wait_for_check_xfer(adap);
423	if (rtn)
424		return rtn;
425
426	for (wrcount = 0; wrcount < length; ++wrcount) {
427		/* write buffer value to I2C data register */
428		iowrite32(buf[wrcount], p + PCH_I2CDR);
429		pch_dbg(adap, "writing %x to Data register\n", buf[wrcount]);
430
431		rtn = pch_i2c_wait_for_check_xfer(adap);
432		if (rtn)
433			return rtn;
434
435		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMCF_BIT);
436		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT);
437	}
438
439	/* check if this is the last message */
440	if (last)
441		pch_i2c_stop(adap);
442	else
443		pch_i2c_repstart(adap);
444
445	pch_dbg(adap, "return=%d\n", wrcount);
446
447	return wrcount;
448}
449
450/**
451 * pch_i2c_sendack() - send ACK
452 * @adap:	Pointer to struct i2c_algo_pch_data.
453 */
454static void pch_i2c_sendack(struct i2c_algo_pch_data *adap)
455{
456	void __iomem *p = adap->pch_base_address;
457	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
458	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
459}
460
461/**
462 * pch_i2c_sendnack() - send NACK
463 * @adap:	Pointer to struct i2c_algo_pch_data.
464 */
465static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap)
466{
467	void __iomem *p = adap->pch_base_address;
468	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
469	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
470}
471
472/**
473 * pch_i2c_restart() - Generate I2C restart condition in normal mode.
474 * @adap:	Pointer to struct i2c_algo_pch_data.
475 *
476 * Generate I2C restart condition in normal mode by setting I2CCTL.I2CRSTA.
477 */
478static void pch_i2c_restart(struct i2c_algo_pch_data *adap)
479{
480	void __iomem *p = adap->pch_base_address;
481	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
482	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_RESTART);
483}
484
485/**
486 * pch_i2c_readbytes() - read data  from I2C bus in normal mode.
487 * @i2c_adap:	Pointer to the struct i2c_adapter.
488 * @msgs:	Pointer to i2c_msg structure.
489 * @last:	specifies whether last message or not.
490 * @first:	specifies whether first message or not.
491 */
492static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
493			     u32 last, u32 first)
494{
495	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
496
497	u8 *buf;
498	u32 count;
499	u32 length;
500	u32 addr;
501	u32 addr_2_msb;
502	u32 addr_8_lsb;
503	void __iomem *p = adap->pch_base_address;
504	s32 rtn;
505
506	length = msgs->len;
507	buf = msgs->buf;
508	addr = msgs->addr;
509
510	/* enable master reception */
511	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
512
513	if (first) {
514		if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
515			return -ETIME;
516	}
517
518	if (msgs->flags & I2C_M_TEN) {
519		addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7);
520		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
521		if (first)
522			pch_i2c_start(adap);
523
524		rtn = pch_i2c_wait_for_check_xfer(adap);
525		if (rtn)
526			return rtn;
527
528		addr_8_lsb = (addr & I2C_ADDR_MSK);
529		iowrite32(addr_8_lsb, p + PCH_I2CDR);
530
531		pch_i2c_restart(adap);
532
533		rtn = pch_i2c_wait_for_check_xfer(adap);
534		if (rtn)
535			return rtn;
536
537		addr_2_msb |= I2C_RD;
538		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
539	} else {
540		/* 7 address bits + R/W bit */
541		addr = (((addr) << 1) | (I2C_RD));
542		iowrite32(addr, p + PCH_I2CDR);
543	}
544
545	/* check if it is the first message */
546	if (first)
547		pch_i2c_start(adap);
548
549	rtn = pch_i2c_wait_for_check_xfer(adap);
550	if (rtn)
551		return rtn;
552
553	if (length == 0) {
554		pch_i2c_stop(adap);
555		ioread32(p + PCH_I2CDR); /* Dummy read needs */
556
557		count = length;
558	} else {
559		int read_index;
560		int loop;
561		pch_i2c_sendack(adap);
562
563		/* Dummy read */
564		for (loop = 1, read_index = 0; loop < length; loop++) {
565			buf[read_index] = ioread32(p + PCH_I2CDR);
566
567			if (loop != 1)
568				read_index++;
569
570			rtn = pch_i2c_wait_for_check_xfer(adap);
571			if (rtn)
572				return rtn;
573		}	/* end for */
574
575		pch_i2c_sendnack(adap);
576
577		buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */
578
579		if (length != 1)
580			read_index++;
581
582		rtn = pch_i2c_wait_for_check_xfer(adap);
583		if (rtn)
584			return rtn;
585
586		if (last)
587			pch_i2c_stop(adap);
588		else
589			pch_i2c_repstart(adap);
590
591		buf[read_index++] = ioread32(p + PCH_I2CDR); /* Read Final */
592		count = read_index;
593	}
594
595	return count;
596}
597
598/**
599 * pch_i2c_cb() - Interrupt handler Call back function
600 * @adap:	Pointer to struct i2c_algo_pch_data.
601 */
602static void pch_i2c_cb(struct i2c_algo_pch_data *adap)
603{
604	u32 sts;
605	void __iomem *p = adap->pch_base_address;
606
607	sts = ioread32(p + PCH_I2CSR);
608	sts &= (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT);
609	if (sts & I2CMAL_BIT)
610		adap->pch_event_flag |= I2CMAL_EVENT;
611
612	if (sts & I2CMCF_BIT)
613		adap->pch_event_flag |= I2CMCF_EVENT;
614
615	/* clear the applicable bits */
616	pch_clrbit(adap->pch_base_address, PCH_I2CSR, sts);
617
618	pch_dbg(adap, "PCH_I2CSR = %x\n", ioread32(p + PCH_I2CSR));
619
620	wake_up(&pch_event);
621}
622
623/**
624 * pch_i2c_handler() - interrupt handler for the PCH I2C controller
625 * @irq:	irq number.
626 * @pData:	cookie passed back to the handler function.
627 */
628static irqreturn_t pch_i2c_handler(int irq, void *pData)
629{
630	u32 reg_val;
631	int flag;
632	int i;
633	struct adapter_info *adap_info = pData;
634	void __iomem *p;
635	u32 mode;
636
637	for (i = 0, flag = 0; i < adap_info->ch_num; i++) {
638		p = adap_info->pch_data[i].pch_base_address;
639		mode = ioread32(p + PCH_I2CMOD);
640		mode &= BUFFER_MODE | EEPROM_SR_MODE;
641		if (mode != NORMAL_MODE) {
642			pch_err(adap_info->pch_data,
643				"I2C-%d mode(%d) is not supported\n", mode, i);
644			continue;
645		}
646		reg_val = ioread32(p + PCH_I2CSR);
647		if (reg_val & (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT)) {
648			pch_i2c_cb(&adap_info->pch_data[i]);
649			flag = 1;
650		}
651	}
652
653	return flag ? IRQ_HANDLED : IRQ_NONE;
654}
655
656/**
657 * pch_i2c_xfer() - Reading adnd writing data through I2C bus
658 * @i2c_adap:	Pointer to the struct i2c_adapter.
659 * @msgs:	Pointer to i2c_msg structure.
660 * @num:	number of messages.
661 */
662static s32 pch_i2c_xfer(struct i2c_adapter *i2c_adap,
663			struct i2c_msg *msgs, s32 num)
664{
665	struct i2c_msg *pmsg;
666	u32 i = 0;
667	u32 status;
668	s32 ret;
669
670	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
671
672	ret = mutex_lock_interruptible(&pch_mutex);
673	if (ret)
674		return ret;
675
676	if (adap->p_adapter_info->pch_i2c_suspended) {
677		mutex_unlock(&pch_mutex);
678		return -EBUSY;
679	}
680
681	pch_dbg(adap, "adap->p_adapter_info->pch_i2c_suspended is %d\n",
682		adap->p_adapter_info->pch_i2c_suspended);
683	/* transfer not completed */
684	adap->pch_i2c_xfer_in_progress = true;
685
686	for (i = 0; i < num && ret >= 0; i++) {
687		pmsg = &msgs[i];
688		pmsg->flags |= adap->pch_buff_mode_en;
689		status = pmsg->flags;
690		pch_dbg(adap,
691			"After invoking I2C_MODE_SEL :flag= 0x%x\n", status);
692
693		if ((status & (I2C_M_RD)) != false) {
694			ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num),
695						(i == 0));
696		} else {
697			ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num),
698						 (i == 0));
699		}
700	}
701
702	adap->pch_i2c_xfer_in_progress = false;	/* transfer completed */
703
704	mutex_unlock(&pch_mutex);
705
706	return (ret < 0) ? ret : num;
707}
708
709/**
710 * pch_i2c_func() - return the functionality of the I2C driver
711 * @adap:	Pointer to struct i2c_algo_pch_data.
712 */
713static u32 pch_i2c_func(struct i2c_adapter *adap)
714{
715	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
716}
717
718static struct i2c_algorithm pch_algorithm = {
719	.master_xfer = pch_i2c_xfer,
720	.functionality = pch_i2c_func
721};
722
723/**
724 * pch_i2c_disbl_int() - Disable PCH I2C interrupts
725 * @adap:	Pointer to struct i2c_algo_pch_data.
726 */
727static void pch_i2c_disbl_int(struct i2c_algo_pch_data *adap)
728{
729	void __iomem *p = adap->pch_base_address;
730
731	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, NORMAL_INTR_ENBL);
732
733	iowrite32(EEPROM_RST_INTR_DISBL, p + PCH_I2CESRMSK);
734
735	iowrite32(BUFFER_MODE_INTR_DISBL, p + PCH_I2CBUFMSK);
736}
737
738static int pch_i2c_probe(struct pci_dev *pdev,
739				   const struct pci_device_id *id)
740{
741	void __iomem *base_addr;
742	int ret;
743	int i, j;
744	struct adapter_info *adap_info;
745	struct i2c_adapter *pch_adap;
746
747	pch_pci_dbg(pdev, "Entered.\n");
748
749	adap_info = kzalloc((sizeof(struct adapter_info)), GFP_KERNEL);
750	if (adap_info == NULL)
751		return -ENOMEM;
752
753	ret = pci_enable_device(pdev);
754	if (ret) {
755		pch_pci_err(pdev, "pci_enable_device FAILED\n");
756		goto err_pci_enable;
757	}
758
759	ret = pci_request_regions(pdev, KBUILD_MODNAME);
760	if (ret) {
761		pch_pci_err(pdev, "pci_request_regions FAILED\n");
762		goto err_pci_req;
763	}
764
765	base_addr = pci_iomap(pdev, 1, 0);
766
767	if (base_addr == NULL) {
768		pch_pci_err(pdev, "pci_iomap FAILED\n");
769		ret = -ENOMEM;
770		goto err_pci_iomap;
771	}
772
773	/* Set the number of I2C channel instance */
774	adap_info->ch_num = id->driver_data;
775
776	ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED,
777		  KBUILD_MODNAME, adap_info);
778	if (ret) {
779		pch_pci_err(pdev, "request_irq FAILED\n");
780		goto err_request_irq;
781	}
782
783	for (i = 0; i < adap_info->ch_num; i++) {
784		pch_adap = &adap_info->pch_data[i].pch_adapter;
785		adap_info->pch_i2c_suspended = false;
786
787		adap_info->pch_data[i].p_adapter_info = adap_info;
788
789		pch_adap->owner = THIS_MODULE;
790		pch_adap->class = I2C_CLASS_HWMON;
791		strlcpy(pch_adap->name, KBUILD_MODNAME, sizeof(pch_adap->name));
792		pch_adap->algo = &pch_algorithm;
793		pch_adap->algo_data = &adap_info->pch_data[i];
794
795		/* base_addr + offset; */
796		adap_info->pch_data[i].pch_base_address = base_addr + 0x100 * i;
797
798		pch_adap->dev.parent = &pdev->dev;
799
800		pch_i2c_init(&adap_info->pch_data[i]);
801
802		pch_adap->nr = i;
803		ret = i2c_add_numbered_adapter(pch_adap);
804		if (ret) {
805			pch_pci_err(pdev, "i2c_add_adapter[ch:%d] FAILED\n", i);
806			goto err_add_adapter;
807		}
808	}
809
810	pci_set_drvdata(pdev, adap_info);
811	pch_pci_dbg(pdev, "returns %d.\n", ret);
812	return 0;
813
814err_add_adapter:
815	for (j = 0; j < i; j++)
816		i2c_del_adapter(&adap_info->pch_data[j].pch_adapter);
817	free_irq(pdev->irq, adap_info);
818err_request_irq:
819	pci_iounmap(pdev, base_addr);
820err_pci_iomap:
821	pci_release_regions(pdev);
822err_pci_req:
823	pci_disable_device(pdev);
824err_pci_enable:
825	kfree(adap_info);
826	return ret;
827}
828
829static void pch_i2c_remove(struct pci_dev *pdev)
830{
831	int i;
832	struct adapter_info *adap_info = pci_get_drvdata(pdev);
833
834	free_irq(pdev->irq, adap_info);
835
836	for (i = 0; i < adap_info->ch_num; i++) {
837		pch_i2c_disbl_int(&adap_info->pch_data[i]);
838		i2c_del_adapter(&adap_info->pch_data[i].pch_adapter);
839	}
840
841	if (adap_info->pch_data[0].pch_base_address)
842		pci_iounmap(pdev, adap_info->pch_data[0].pch_base_address);
843
844	for (i = 0; i < adap_info->ch_num; i++)
845		adap_info->pch_data[i].pch_base_address = NULL;
846
847	pci_release_regions(pdev);
848
849	pci_disable_device(pdev);
850	kfree(adap_info);
851}
852
853#ifdef CONFIG_PM
854static int pch_i2c_suspend(struct pci_dev *pdev, pm_message_t state)
855{
856	int ret;
857	int i;
858	struct adapter_info *adap_info = pci_get_drvdata(pdev);
859	void __iomem *p = adap_info->pch_data[0].pch_base_address;
860
861	adap_info->pch_i2c_suspended = true;
862
863	for (i = 0; i < adap_info->ch_num; i++) {
864		while ((adap_info->pch_data[i].pch_i2c_xfer_in_progress)) {
865			/* Wait until all channel transfers are completed */
866			msleep(20);
867		}
868	}
869
870	/* Disable the i2c interrupts */
871	for (i = 0; i < adap_info->ch_num; i++)
872		pch_i2c_disbl_int(&adap_info->pch_data[i]);
873
874	pch_pci_dbg(pdev, "I2CSR = %x I2CBUFSTA = %x I2CESRSTA = %x "
875		"invoked function pch_i2c_disbl_int successfully\n",
876		ioread32(p + PCH_I2CSR), ioread32(p + PCH_I2CBUFSTA),
877		ioread32(p + PCH_I2CESRSTA));
878
879	ret = pci_save_state(pdev);
880
881	if (ret) {
882		pch_pci_err(pdev, "pci_save_state\n");
883		return ret;
884	}
885
886	pci_enable_wake(pdev, PCI_D3hot, 0);
887	pci_disable_device(pdev);
888	pci_set_power_state(pdev, pci_choose_state(pdev, state));
889
890	return 0;
891}
892
893static int pch_i2c_resume(struct pci_dev *pdev)
894{
895	int i;
896	struct adapter_info *adap_info = pci_get_drvdata(pdev);
897
898	pci_set_power_state(pdev, PCI_D0);
899	pci_restore_state(pdev);
900
901	if (pci_enable_device(pdev) < 0) {
902		pch_pci_err(pdev, "pch_i2c_resume:pci_enable_device FAILED\n");
903		return -EIO;
904	}
905
906	pci_enable_wake(pdev, PCI_D3hot, 0);
907
908	for (i = 0; i < adap_info->ch_num; i++)
909		pch_i2c_init(&adap_info->pch_data[i]);
910
911	adap_info->pch_i2c_suspended = false;
912
913	return 0;
914}
915#else
916#define pch_i2c_suspend NULL
917#define pch_i2c_resume NULL
918#endif
919
920static struct pci_driver pch_pcidriver = {
921	.name = KBUILD_MODNAME,
922	.id_table = pch_pcidev_id,
923	.probe = pch_i2c_probe,
924	.remove = pch_i2c_remove,
925	.suspend = pch_i2c_suspend,
926	.resume = pch_i2c_resume
927};
928
929module_pci_driver(pch_pcidriver);
930
931MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semico ML7213/ML7223/ML7831 IOH I2C");
932MODULE_LICENSE("GPL");
933MODULE_AUTHOR("Tomoya MORINAGA. <tomoya.rohm@gmail.com>");
934module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR));
935module_param(pch_clk, int, (S_IRUSR | S_IWUSR));
936