1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
4 */
5
6#include <linux/module.h>
7#include <linux/kernel.h>
8#include <linux/delay.h>
9#include <linux/errno.h>
10#include <linux/i2c.h>
11#include <linux/fs.h>
12#include <linux/io.h>
13#include <linux/types.h>
14#include <linux/interrupt.h>
15#include <linux/jiffies.h>
16#include <linux/pci.h>
17#include <linux/mutex.h>
18#include <linux/ktime.h>
19#include <linux/slab.h>
20
21#define PCH_EVENT_SET	0	/* I2C Interrupt Event Set Status */
22#define PCH_EVENT_NONE	1	/* I2C Interrupt Event Clear Status */
23#define PCH_MAX_CLK		100000	/* Maximum Clock speed in MHz */
24#define PCH_BUFFER_MODE_ENABLE	0x0002	/* flag for Buffer mode enable */
25#define PCH_EEPROM_SW_RST_MODE_ENABLE	0x0008	/* EEPROM SW RST enable flag */
26
27#define PCH_I2CSADR	0x00	/* I2C slave address register */
28#define PCH_I2CCTL	0x04	/* I2C control register */
29#define PCH_I2CSR	0x08	/* I2C status register */
30#define PCH_I2CDR	0x0C	/* I2C data register */
31#define PCH_I2CMON	0x10	/* I2C bus monitor register */
32#define PCH_I2CBC	0x14	/* I2C bus transfer rate setup counter */
33#define PCH_I2CMOD	0x18	/* I2C mode register */
34#define PCH_I2CBUFSLV	0x1C	/* I2C buffer mode slave address register */
35#define PCH_I2CBUFSUB	0x20	/* I2C buffer mode subaddress register */
36#define PCH_I2CBUFFOR	0x24	/* I2C buffer mode format register */
37#define PCH_I2CBUFCTL	0x28	/* I2C buffer mode control register */
38#define PCH_I2CBUFMSK	0x2C	/* I2C buffer mode interrupt mask register */
39#define PCH_I2CBUFSTA	0x30	/* I2C buffer mode status register */
40#define PCH_I2CBUFLEV	0x34	/* I2C buffer mode level register */
41#define PCH_I2CESRFOR	0x38	/* EEPROM software reset mode format register */
42#define PCH_I2CESRCTL	0x3C	/* EEPROM software reset mode ctrl register */
43#define PCH_I2CESRMSK	0x40	/* EEPROM software reset mode */
44#define PCH_I2CESRSTA	0x44	/* EEPROM software reset mode status register */
45#define PCH_I2CTMR	0x48	/* I2C timer register */
46#define PCH_I2CSRST	0xFC	/* I2C reset register */
47#define PCH_I2CNF	0xF8	/* I2C noise filter register */
48
49#define BUS_IDLE_TIMEOUT	20
50#define PCH_I2CCTL_I2CMEN	0x0080
51#define TEN_BIT_ADDR_DEFAULT	0xF000
52#define TEN_BIT_ADDR_MASK	0xF0
53#define PCH_START		0x0020
54#define PCH_RESTART		0x0004
55#define PCH_ESR_START		0x0001
56#define PCH_BUFF_START		0x1
57#define PCH_REPSTART		0x0004
58#define PCH_ACK			0x0008
59#define PCH_GETACK		0x0001
60#define CLR_REG			0x0
61#define I2C_RD			0x1
62#define I2CMCF_BIT		0x0080
63#define I2CMIF_BIT		0x0002
64#define I2CMAL_BIT		0x0010
65#define I2CBMFI_BIT		0x0001
66#define I2CBMAL_BIT		0x0002
67#define I2CBMNA_BIT		0x0004
68#define I2CBMTO_BIT		0x0008
69#define I2CBMIS_BIT		0x0010
70#define I2CESRFI_BIT		0X0001
71#define I2CESRTO_BIT		0x0002
72#define I2CESRFIIE_BIT		0x1
73#define I2CESRTOIE_BIT		0x2
74#define I2CBMDZ_BIT		0x0040
75#define I2CBMAG_BIT		0x0020
76#define I2CMBB_BIT		0x0020
77#define BUFFER_MODE_MASK	(I2CBMFI_BIT | I2CBMAL_BIT | I2CBMNA_BIT | \
78				I2CBMTO_BIT | I2CBMIS_BIT)
79#define I2C_ADDR_MSK		0xFF
80#define I2C_MSB_2B_MSK		0x300
81#define FAST_MODE_CLK		400
82#define FAST_MODE_EN		0x0001
83#define SUB_ADDR_LEN_MAX	4
84#define BUF_LEN_MAX		32
85#define PCH_BUFFER_MODE		0x1
86#define EEPROM_SW_RST_MODE	0x0002
87#define NORMAL_INTR_ENBL	0x0300
88#define EEPROM_RST_INTR_ENBL	(I2CESRFIIE_BIT | I2CESRTOIE_BIT)
89#define EEPROM_RST_INTR_DISBL	0x0
90#define BUFFER_MODE_INTR_ENBL	0x001F
91#define BUFFER_MODE_INTR_DISBL	0x0
92#define NORMAL_MODE		0x0
93#define BUFFER_MODE		0x1
94#define EEPROM_SR_MODE		0x2
95#define I2C_TX_MODE		0x0010
96#define PCH_BUF_TX		0xFFF7
97#define PCH_BUF_RD		0x0008
98#define I2C_ERROR_MASK	(I2CESRTO_EVENT | I2CBMIS_EVENT | I2CBMTO_EVENT | \
99			I2CBMNA_EVENT | I2CBMAL_EVENT | I2CMAL_EVENT)
100#define I2CMAL_EVENT		0x0001
101#define I2CMCF_EVENT		0x0002
102#define I2CBMFI_EVENT		0x0004
103#define I2CBMAL_EVENT		0x0008
104#define I2CBMNA_EVENT		0x0010
105#define I2CBMTO_EVENT		0x0020
106#define I2CBMIS_EVENT		0x0040
107#define I2CESRFI_EVENT		0x0080
108#define I2CESRTO_EVENT		0x0100
109#define PCI_DEVICE_ID_PCH_I2C	0x8817
110
111#define pch_dbg(adap, fmt, arg...)  \
112	dev_dbg(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
113
114#define pch_err(adap, fmt, arg...)  \
115	dev_err(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
116
117#define pch_pci_err(pdev, fmt, arg...)  \
118	dev_err(&pdev->dev, "%s :" fmt, __func__, ##arg)
119
120#define pch_pci_dbg(pdev, fmt, arg...)  \
121	dev_dbg(&pdev->dev, "%s :" fmt, __func__, ##arg)
122
123/*
124Set the number of I2C instance max
125Intel EG20T PCH :		1ch
126LAPIS Semiconductor ML7213 IOH :	2ch
127LAPIS Semiconductor ML7831 IOH :	1ch
128*/
129#define PCH_I2C_MAX_DEV			2
130
131/**
132 * struct i2c_algo_pch_data - for I2C driver functionalities
133 * @pch_adapter:		stores the reference to i2c_adapter structure
134 * @p_adapter_info:		stores the reference to adapter_info structure
135 * @pch_base_address:		specifies the remapped base address
136 * @pch_buff_mode_en:		specifies if buffer mode is enabled
137 * @pch_event_flag:		specifies occurrence of interrupt events
138 * @pch_i2c_xfer_in_progress:	specifies whether the transfer is completed
139 */
140struct i2c_algo_pch_data {
141	struct i2c_adapter pch_adapter;
142	struct adapter_info *p_adapter_info;
143	void __iomem *pch_base_address;
144	int pch_buff_mode_en;
145	u32 pch_event_flag;
146	bool pch_i2c_xfer_in_progress;
147};
148
149/**
150 * struct adapter_info - This structure holds the adapter information for the
151			 PCH i2c controller
152 * @pch_data:		stores a list of i2c_algo_pch_data
153 * @pch_i2c_suspended:	specifies whether the system is suspended or not
154 *			perhaps with more lines and words.
155 * @ch_num:		specifies the number of i2c instance
156 *
157 * pch_data has as many elements as maximum I2C channels
158 */
159struct adapter_info {
160	struct i2c_algo_pch_data pch_data[PCH_I2C_MAX_DEV];
161	bool pch_i2c_suspended;
162	int ch_num;
163};
164
165
166static int pch_i2c_speed = 100; /* I2C bus speed in Kbps */
167static int pch_clk = 50000;	/* specifies I2C clock speed in KHz */
168static wait_queue_head_t pch_event;
169static DEFINE_MUTEX(pch_mutex);
170
171/* Definition for ML7213 by LAPIS Semiconductor */
172#define PCI_DEVICE_ID_ML7213_I2C	0x802D
173#define PCI_DEVICE_ID_ML7223_I2C	0x8010
174#define PCI_DEVICE_ID_ML7831_I2C	0x8817
175
176static const struct pci_device_id pch_pcidev_id[] = {
177	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_I2C),   1, },
178	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_I2C), 2, },
179	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_I2C), 1, },
180	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_I2C), 1, },
181	{0,}
182};
183MODULE_DEVICE_TABLE(pci, pch_pcidev_id);
184
185static irqreturn_t pch_i2c_handler(int irq, void *pData);
186
187static inline void pch_setbit(void __iomem *addr, u32 offset, u32 bitmask)
188{
189	u32 val;
190	val = ioread32(addr + offset);
191	val |= bitmask;
192	iowrite32(val, addr + offset);
193}
194
195static inline void pch_clrbit(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
203/**
204 * pch_i2c_init() - hardware initialization of I2C module
205 * @adap:	Pointer to struct i2c_algo_pch_data.
206 */
207static void pch_i2c_init(struct i2c_algo_pch_data *adap)
208{
209	void __iomem *p = adap->pch_base_address;
210	u32 pch_i2cbc;
211	u32 pch_i2ctmr;
212	u32 reg_value;
213
214	/* reset I2C controller */
215	iowrite32(0x01, p + PCH_I2CSRST);
216	msleep(20);
217	iowrite32(0x0, p + PCH_I2CSRST);
218
219	/* Initialize I2C registers */
220	iowrite32(0x21, p + PCH_I2CNF);
221
222	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_I2CCTL_I2CMEN);
223
224	if (pch_i2c_speed != 400)
225		pch_i2c_speed = 100;
226
227	reg_value = PCH_I2CCTL_I2CMEN;
228	if (pch_i2c_speed == FAST_MODE_CLK) {
229		reg_value |= FAST_MODE_EN;
230		pch_dbg(adap, "Fast mode enabled\n");
231	}
232
233	if (pch_clk > PCH_MAX_CLK)
234		pch_clk = 62500;
235
236	pch_i2cbc = (pch_clk + (pch_i2c_speed * 4)) / (pch_i2c_speed * 8);
237	/* Set transfer speed in I2CBC */
238	iowrite32(pch_i2cbc, p + PCH_I2CBC);
239
240	pch_i2ctmr = (pch_clk) / 8;
241	iowrite32(pch_i2ctmr, p + PCH_I2CTMR);
242
243	reg_value |= NORMAL_INTR_ENBL;	/* Enable interrupts in normal mode */
244	iowrite32(reg_value, p + PCH_I2CCTL);
245
246	pch_dbg(adap,
247		"I2CCTL=%x pch_i2cbc=%x pch_i2ctmr=%x Enable interrupts\n",
248		ioread32(p + PCH_I2CCTL), pch_i2cbc, pch_i2ctmr);
249
250	init_waitqueue_head(&pch_event);
251}
252
253/**
254 * pch_i2c_wait_for_bus_idle() - check the status of bus.
255 * @adap:	Pointer to struct i2c_algo_pch_data.
256 * @timeout:	waiting time counter (ms).
257 */
258static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap,
259				     s32 timeout)
260{
261	void __iomem *p = adap->pch_base_address;
262	int schedule = 0;
263	unsigned long end = jiffies + msecs_to_jiffies(timeout);
264
265	while (ioread32(p + PCH_I2CSR) & I2CMBB_BIT) {
266		if (time_after(jiffies, end)) {
267			pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR));
268			pch_err(adap, "%s: Timeout Error.return%d\n",
269					__func__, -ETIME);
270			pch_i2c_init(adap);
271
272			return -ETIME;
273		}
274
275		if (!schedule)
276			/* Retry after some usecs */
277			udelay(5);
278		else
279			/* Wait a bit more without consuming CPU */
280			usleep_range(20, 1000);
281
282		schedule = 1;
283	}
284
285	return 0;
286}
287
288/**
289 * pch_i2c_start() - Generate I2C start condition in normal mode.
290 * @adap:	Pointer to struct i2c_algo_pch_data.
291 *
292 * Generate I2C start condition in normal mode by setting I2CCTL.I2CMSTA to 1.
293 */
294static void pch_i2c_start(struct i2c_algo_pch_data *adap)
295{
296	void __iomem *p = adap->pch_base_address;
297	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
298	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
299}
300
301/**
302 * pch_i2c_stop() - generate stop condition in normal mode.
303 * @adap:	Pointer to struct i2c_algo_pch_data.
304 */
305static void pch_i2c_stop(struct i2c_algo_pch_data *adap)
306{
307	void __iomem *p = adap->pch_base_address;
308	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
309	/* clear the start bit */
310	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
311}
312
313static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap)
314{
315	long ret;
316	void __iomem *p = adap->pch_base_address;
317
318	ret = wait_event_timeout(pch_event,
319			(adap->pch_event_flag != 0), msecs_to_jiffies(1000));
320	if (!ret) {
321		pch_err(adap, "%s:wait-event timeout\n", __func__);
322		adap->pch_event_flag = 0;
323		pch_i2c_stop(adap);
324		pch_i2c_init(adap);
325		return -ETIMEDOUT;
326	}
327
328	if (adap->pch_event_flag & I2C_ERROR_MASK) {
329		pch_err(adap, "Lost Arbitration\n");
330		adap->pch_event_flag = 0;
331		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT);
332		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT);
333		pch_i2c_init(adap);
334		return -EAGAIN;
335	}
336
337	adap->pch_event_flag = 0;
338
339	if (ioread32(p + PCH_I2CSR) & PCH_GETACK) {
340		pch_dbg(adap, "Receive NACK for slave address setting\n");
341		return -ENXIO;
342	}
343
344	return 0;
345}
346
347/**
348 * pch_i2c_repstart() - generate repeated start condition in normal mode
349 * @adap:	Pointer to struct i2c_algo_pch_data.
350 */
351static void pch_i2c_repstart(struct i2c_algo_pch_data *adap)
352{
353	void __iomem *p = adap->pch_base_address;
354	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
355	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_REPSTART);
356}
357
358/**
359 * pch_i2c_writebytes() - write data to I2C bus in normal mode
360 * @i2c_adap:	Pointer to the struct i2c_adapter.
361 * @last:	specifies whether last message or not.
362 *		In the case of compound mode it will be 1 for last message,
363 *		otherwise 0.
364 * @first:	specifies whether first message or not.
365 *		1 for first message otherwise 0.
366 */
367static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
368			      struct i2c_msg *msgs, u32 last, u32 first)
369{
370	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
371	u8 *buf;
372	u32 length;
373	u32 addr;
374	u32 addr_2_msb;
375	u32 addr_8_lsb;
376	s32 wrcount;
377	s32 rtn;
378	void __iomem *p = adap->pch_base_address;
379
380	length = msgs->len;
381	buf = msgs->buf;
382	addr = msgs->addr;
383
384	/* enable master tx */
385	pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
386
387	pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL),
388		length);
389
390	if (first) {
391		if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
392			return -ETIME;
393	}
394
395	if (msgs->flags & I2C_M_TEN) {
396		addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7) & 0x06;
397		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
398		if (first)
399			pch_i2c_start(adap);
400
401		rtn = pch_i2c_wait_for_check_xfer(adap);
402		if (rtn)
403			return rtn;
404
405		addr_8_lsb = (addr & I2C_ADDR_MSK);
406		iowrite32(addr_8_lsb, p + PCH_I2CDR);
407	} else {
408		/* set 7 bit slave address and R/W bit as 0 */
409		iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR);
410		if (first)
411			pch_i2c_start(adap);
412	}
413
414	rtn = pch_i2c_wait_for_check_xfer(adap);
415	if (rtn)
416		return rtn;
417
418	for (wrcount = 0; wrcount < length; ++wrcount) {
419		/* write buffer value to I2C data register */
420		iowrite32(buf[wrcount], p + PCH_I2CDR);
421		pch_dbg(adap, "writing %x to Data register\n", buf[wrcount]);
422
423		rtn = pch_i2c_wait_for_check_xfer(adap);
424		if (rtn)
425			return rtn;
426
427		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMCF_BIT);
428		pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT);
429	}
430
431	/* check if this is the last message */
432	if (last)
433		pch_i2c_stop(adap);
434	else
435		pch_i2c_repstart(adap);
436
437	pch_dbg(adap, "return=%d\n", wrcount);
438
439	return wrcount;
440}
441
442/**
443 * pch_i2c_sendack() - send ACK
444 * @adap:	Pointer to struct i2c_algo_pch_data.
445 */
446static void pch_i2c_sendack(struct i2c_algo_pch_data *adap)
447{
448	void __iomem *p = adap->pch_base_address;
449	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
450	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
451}
452
453/**
454 * pch_i2c_sendnack() - send NACK
455 * @adap:	Pointer to struct i2c_algo_pch_data.
456 */
457static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap)
458{
459	void __iomem *p = adap->pch_base_address;
460	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
461	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
462}
463
464/**
465 * pch_i2c_restart() - Generate I2C restart condition in normal mode.
466 * @adap:	Pointer to struct i2c_algo_pch_data.
467 *
468 * Generate I2C restart condition in normal mode by setting I2CCTL.I2CRSTA.
469 */
470static void pch_i2c_restart(struct i2c_algo_pch_data *adap)
471{
472	void __iomem *p = adap->pch_base_address;
473	pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
474	pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_RESTART);
475}
476
477/**
478 * pch_i2c_readbytes() - read data  from I2C bus in normal mode.
479 * @i2c_adap:	Pointer to the struct i2c_adapter.
480 * @msgs:	Pointer to i2c_msg structure.
481 * @last:	specifies whether last message or not.
482 * @first:	specifies whether first message or not.
483 */
484static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
485			     u32 last, u32 first)
486{
487	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
488
489	u8 *buf;
490	u32 count;
491	u32 length;
492	u32 addr;
493	u32 addr_2_msb;
494	u32 addr_8_lsb;
495	void __iomem *p = adap->pch_base_address;
496	s32 rtn;
497
498	length = msgs->len;
499	buf = msgs->buf;
500	addr = msgs->addr;
501
502	/* enable master reception */
503	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
504
505	if (first) {
506		if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
507			return -ETIME;
508	}
509
510	if (msgs->flags & I2C_M_TEN) {
511		addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7);
512		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
513		if (first)
514			pch_i2c_start(adap);
515
516		rtn = pch_i2c_wait_for_check_xfer(adap);
517		if (rtn)
518			return rtn;
519
520		addr_8_lsb = (addr & I2C_ADDR_MSK);
521		iowrite32(addr_8_lsb, p + PCH_I2CDR);
522
523		pch_i2c_restart(adap);
524
525		rtn = pch_i2c_wait_for_check_xfer(adap);
526		if (rtn)
527			return rtn;
528
529		addr_2_msb |= I2C_RD;
530		iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
531	} else {
532		/* 7 address bits + R/W bit */
533		iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR);
534	}
535
536	/* check if it is the first message */
537	if (first)
538		pch_i2c_start(adap);
539
540	rtn = pch_i2c_wait_for_check_xfer(adap);
541	if (rtn)
542		return rtn;
543
544	if (length == 0) {
545		pch_i2c_stop(adap);
546		ioread32(p + PCH_I2CDR); /* Dummy read needs */
547
548		count = length;
549	} else {
550		int read_index;
551		int loop;
552		pch_i2c_sendack(adap);
553
554		/* Dummy read */
555		for (loop = 1, read_index = 0; loop < length; loop++) {
556			buf[read_index] = ioread32(p + PCH_I2CDR);
557
558			if (loop != 1)
559				read_index++;
560
561			rtn = pch_i2c_wait_for_check_xfer(adap);
562			if (rtn)
563				return rtn;
564		}	/* end for */
565
566		pch_i2c_sendnack(adap);
567
568		buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */
569
570		if (length != 1)
571			read_index++;
572
573		rtn = pch_i2c_wait_for_check_xfer(adap);
574		if (rtn)
575			return rtn;
576
577		if (last)
578			pch_i2c_stop(adap);
579		else
580			pch_i2c_repstart(adap);
581
582		buf[read_index++] = ioread32(p + PCH_I2CDR); /* Read Final */
583		count = read_index;
584	}
585
586	return count;
587}
588
589/**
590 * pch_i2c_cb() - Interrupt handler Call back function
591 * @adap:	Pointer to struct i2c_algo_pch_data.
592 */
593static void pch_i2c_cb(struct i2c_algo_pch_data *adap)
594{
595	u32 sts;
596	void __iomem *p = adap->pch_base_address;
597
598	sts = ioread32(p + PCH_I2CSR);
599	sts &= (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT);
600	if (sts & I2CMAL_BIT)
601		adap->pch_event_flag |= I2CMAL_EVENT;
602
603	if (sts & I2CMCF_BIT)
604		adap->pch_event_flag |= I2CMCF_EVENT;
605
606	/* clear the applicable bits */
607	pch_clrbit(adap->pch_base_address, PCH_I2CSR, sts);
608
609	pch_dbg(adap, "PCH_I2CSR = %x\n", ioread32(p + PCH_I2CSR));
610
611	wake_up(&pch_event);
612}
613
614/**
615 * pch_i2c_handler() - interrupt handler for the PCH I2C controller
616 * @irq:	irq number.
617 * @pData:	cookie passed back to the handler function.
618 */
619static irqreturn_t pch_i2c_handler(int irq, void *pData)
620{
621	u32 reg_val;
622	int flag;
623	int i;
624	struct adapter_info *adap_info = pData;
625	void __iomem *p;
626	u32 mode;
627
628	for (i = 0, flag = 0; i < adap_info->ch_num; i++) {
629		p = adap_info->pch_data[i].pch_base_address;
630		mode = ioread32(p + PCH_I2CMOD);
631		mode &= BUFFER_MODE | EEPROM_SR_MODE;
632		if (mode != NORMAL_MODE) {
633			pch_err(adap_info->pch_data,
634				"I2C-%d mode(%d) is not supported\n", mode, i);
635			continue;
636		}
637		reg_val = ioread32(p + PCH_I2CSR);
638		if (reg_val & (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT)) {
639			pch_i2c_cb(&adap_info->pch_data[i]);
640			flag = 1;
641		}
642	}
643
644	return flag ? IRQ_HANDLED : IRQ_NONE;
645}
646
647/**
648 * pch_i2c_xfer() - Reading adnd writing data through I2C bus
649 * @i2c_adap:	Pointer to the struct i2c_adapter.
650 * @msgs:	Pointer to i2c_msg structure.
651 * @num:	number of messages.
652 */
653static s32 pch_i2c_xfer(struct i2c_adapter *i2c_adap,
654			struct i2c_msg *msgs, s32 num)
655{
656	struct i2c_msg *pmsg;
657	u32 i = 0;
658	u32 status;
659	s32 ret;
660
661	struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
662
663	ret = mutex_lock_interruptible(&pch_mutex);
664	if (ret)
665		return ret;
666
667	if (adap->p_adapter_info->pch_i2c_suspended) {
668		mutex_unlock(&pch_mutex);
669		return -EBUSY;
670	}
671
672	pch_dbg(adap, "adap->p_adapter_info->pch_i2c_suspended is %d\n",
673		adap->p_adapter_info->pch_i2c_suspended);
674	/* transfer not completed */
675	adap->pch_i2c_xfer_in_progress = true;
676
677	for (i = 0; i < num && ret >= 0; i++) {
678		pmsg = &msgs[i];
679		pmsg->flags |= adap->pch_buff_mode_en;
680		status = pmsg->flags;
681		pch_dbg(adap,
682			"After invoking I2C_MODE_SEL :flag= 0x%x\n", status);
683
684		if ((status & (I2C_M_RD)) != false) {
685			ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num),
686						(i == 0));
687		} else {
688			ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num),
689						 (i == 0));
690		}
691	}
692
693	adap->pch_i2c_xfer_in_progress = false;	/* transfer completed */
694
695	mutex_unlock(&pch_mutex);
696
697	return (ret < 0) ? ret : num;
698}
699
700/**
701 * pch_i2c_func() - return the functionality of the I2C driver
702 * @adap:	Pointer to struct i2c_algo_pch_data.
703 */
704static u32 pch_i2c_func(struct i2c_adapter *adap)
705{
706	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
707}
708
709static const struct i2c_algorithm pch_algorithm = {
710	.master_xfer = pch_i2c_xfer,
711	.functionality = pch_i2c_func
712};
713
714/**
715 * pch_i2c_disbl_int() - Disable PCH I2C interrupts
716 * @adap:	Pointer to struct i2c_algo_pch_data.
717 */
718static void pch_i2c_disbl_int(struct i2c_algo_pch_data *adap)
719{
720	void __iomem *p = adap->pch_base_address;
721
722	pch_clrbit(adap->pch_base_address, PCH_I2CCTL, NORMAL_INTR_ENBL);
723
724	iowrite32(EEPROM_RST_INTR_DISBL, p + PCH_I2CESRMSK);
725
726	iowrite32(BUFFER_MODE_INTR_DISBL, p + PCH_I2CBUFMSK);
727}
728
729static int pch_i2c_probe(struct pci_dev *pdev,
730				   const struct pci_device_id *id)
731{
732	void __iomem *base_addr;
733	int ret;
734	int i, j;
735	struct adapter_info *adap_info;
736	struct i2c_adapter *pch_adap;
737
738	pch_pci_dbg(pdev, "Entered.\n");
739
740	adap_info = kzalloc((sizeof(struct adapter_info)), GFP_KERNEL);
741	if (adap_info == NULL)
742		return -ENOMEM;
743
744	ret = pci_enable_device(pdev);
745	if (ret) {
746		pch_pci_err(pdev, "pci_enable_device FAILED\n");
747		goto err_pci_enable;
748	}
749
750	ret = pci_request_regions(pdev, KBUILD_MODNAME);
751	if (ret) {
752		pch_pci_err(pdev, "pci_request_regions FAILED\n");
753		goto err_pci_req;
754	}
755
756	base_addr = pci_iomap(pdev, 1, 0);
757
758	if (base_addr == NULL) {
759		pch_pci_err(pdev, "pci_iomap FAILED\n");
760		ret = -ENOMEM;
761		goto err_pci_iomap;
762	}
763
764	/* Set the number of I2C channel instance */
765	adap_info->ch_num = id->driver_data;
766
767	for (i = 0; i < adap_info->ch_num; i++) {
768		pch_adap = &adap_info->pch_data[i].pch_adapter;
769		adap_info->pch_i2c_suspended = false;
770
771		adap_info->pch_data[i].p_adapter_info = adap_info;
772
773		pch_adap->owner = THIS_MODULE;
774		pch_adap->class = I2C_CLASS_HWMON;
775		strlcpy(pch_adap->name, KBUILD_MODNAME, sizeof(pch_adap->name));
776		pch_adap->algo = &pch_algorithm;
777		pch_adap->algo_data = &adap_info->pch_data[i];
778
779		/* base_addr + offset; */
780		adap_info->pch_data[i].pch_base_address = base_addr + 0x100 * i;
781
782		pch_adap->dev.of_node = pdev->dev.of_node;
783		pch_adap->dev.parent = &pdev->dev;
784	}
785
786	ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED,
787		  KBUILD_MODNAME, adap_info);
788	if (ret) {
789		pch_pci_err(pdev, "request_irq FAILED\n");
790		goto err_request_irq;
791	}
792
793	for (i = 0; i < adap_info->ch_num; i++) {
794		pch_adap = &adap_info->pch_data[i].pch_adapter;
795
796		pch_i2c_init(&adap_info->pch_data[i]);
797
798		pch_adap->nr = i;
799		ret = i2c_add_numbered_adapter(pch_adap);
800		if (ret) {
801			pch_pci_err(pdev, "i2c_add_adapter[ch:%d] FAILED\n", i);
802			goto err_add_adapter;
803		}
804	}
805
806	pci_set_drvdata(pdev, adap_info);
807	pch_pci_dbg(pdev, "returns %d.\n", ret);
808	return 0;
809
810err_add_adapter:
811	for (j = 0; j < i; j++)
812		i2c_del_adapter(&adap_info->pch_data[j].pch_adapter);
813	free_irq(pdev->irq, adap_info);
814err_request_irq:
815	pci_iounmap(pdev, base_addr);
816err_pci_iomap:
817	pci_release_regions(pdev);
818err_pci_req:
819	pci_disable_device(pdev);
820err_pci_enable:
821	kfree(adap_info);
822	return ret;
823}
824
825static void pch_i2c_remove(struct pci_dev *pdev)
826{
827	int i;
828	struct adapter_info *adap_info = pci_get_drvdata(pdev);
829
830	free_irq(pdev->irq, adap_info);
831
832	for (i = 0; i < adap_info->ch_num; i++) {
833		pch_i2c_disbl_int(&adap_info->pch_data[i]);
834		i2c_del_adapter(&adap_info->pch_data[i].pch_adapter);
835	}
836
837	if (adap_info->pch_data[0].pch_base_address)
838		pci_iounmap(pdev, adap_info->pch_data[0].pch_base_address);
839
840	for (i = 0; i < adap_info->ch_num; i++)
841		adap_info->pch_data[i].pch_base_address = NULL;
842
843	pci_release_regions(pdev);
844
845	pci_disable_device(pdev);
846	kfree(adap_info);
847}
848
849static int __maybe_unused pch_i2c_suspend(struct device *dev)
850{
851	int i;
852	struct pci_dev *pdev = to_pci_dev(dev);
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	return 0;
875}
876
877static int __maybe_unused pch_i2c_resume(struct device *dev)
878{
879	int i;
880	struct adapter_info *adap_info = dev_get_drvdata(dev);
881
882	for (i = 0; i < adap_info->ch_num; i++)
883		pch_i2c_init(&adap_info->pch_data[i]);
884
885	adap_info->pch_i2c_suspended = false;
886
887	return 0;
888}
889
890static SIMPLE_DEV_PM_OPS(pch_i2c_pm_ops, pch_i2c_suspend, pch_i2c_resume);
891
892static struct pci_driver pch_pcidriver = {
893	.name = KBUILD_MODNAME,
894	.id_table = pch_pcidev_id,
895	.probe = pch_i2c_probe,
896	.remove = pch_i2c_remove,
897	.driver.pm = &pch_i2c_pm_ops,
898};
899
900module_pci_driver(pch_pcidriver);
901
902MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semico ML7213/ML7223/ML7831 IOH I2C");
903MODULE_LICENSE("GPL");
904MODULE_AUTHOR("Tomoya MORINAGA. <tomoya.rohm@gmail.com>");
905module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR));
906module_param(pch_clk, int, (S_IRUSR | S_IWUSR));
907