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Kuninori Morimoto6ccbe602012-09-27 23:44:25 -07001/*
Wolfram Sang3d99bea2014-05-28 09:44:46 +02002 * Driver for the Renesas RCar I2C unit
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -07003 *
Wolfram Sang3d99bea2014-05-28 09:44:46 +02004 * Copyright (C) 2014 Wolfram Sang <wsa@sang-engineering.com>
5 *
6 * Copyright (C) 2012-14 Renesas Solutions Corp.
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -07007 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
8 *
9 * This file is based on the drivers/i2c/busses/i2c-sh7760.c
10 * (c) 2005-2008 MSC Vertriebsges.m.b.H, Manuel Lauss <mlau@msc-ge.com>
11 *
12 * This file used out-of-tree driver i2c-rcar.c
13 * Copyright (C) 2011-2012 Renesas Electronics Corporation
14 *
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
Wolfram Sang3d99bea2014-05-28 09:44:46 +020017 * the Free Software Foundation; version 2 of the License.
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070018 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070023 */
24#include <linux/clk.h>
25#include <linux/delay.h>
26#include <linux/err.h>
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070027#include <linux/interrupt.h>
28#include <linux/io.h>
29#include <linux/i2c.h>
30#include <linux/i2c/i2c-rcar.h>
31#include <linux/kernel.h>
32#include <linux/module.h>
Guennadi Liakhovetski7679c0e2013-09-12 14:36:46 +020033#include <linux/of_device.h>
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070034#include <linux/platform_device.h>
35#include <linux/pm_runtime.h>
36#include <linux/slab.h>
Sergei Shtylyov91bfe292014-08-24 00:44:09 +040037#include <linux/spinlock.h>
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070038
39/* register offsets */
40#define ICSCR 0x00 /* slave ctrl */
41#define ICMCR 0x04 /* master ctrl */
42#define ICSSR 0x08 /* slave status */
43#define ICMSR 0x0C /* master status */
44#define ICSIER 0x10 /* slave irq enable */
45#define ICMIER 0x14 /* master irq enable */
46#define ICCCR 0x18 /* clock dividers */
47#define ICSAR 0x1C /* slave address */
48#define ICMAR 0x20 /* master address */
49#define ICRXTX 0x24 /* data port */
50
Wolfram Sangde20d182014-11-18 17:04:55 +010051/* ICSCR */
52#define SDBS (1 << 3) /* slave data buffer select */
53#define SIE (1 << 2) /* slave interface enable */
54#define GCAE (1 << 1) /* general call address enable */
55#define FNA (1 << 0) /* forced non acknowledgment */
56
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070057/* ICMCR */
58#define MDBS (1 << 7) /* non-fifo mode switch */
59#define FSCL (1 << 6) /* override SCL pin */
60#define FSDA (1 << 5) /* override SDA pin */
61#define OBPC (1 << 4) /* override pins */
62#define MIE (1 << 3) /* master if enable */
63#define TSBE (1 << 2)
64#define FSB (1 << 1) /* force stop bit */
65#define ESG (1 << 0) /* en startbit gen */
66
Wolfram Sangde20d182014-11-18 17:04:55 +010067/* ICSSR (also for ICSIER) */
68#define GCAR (1 << 6) /* general call received */
69#define STM (1 << 5) /* slave transmit mode */
70#define SSR (1 << 4) /* stop received */
71#define SDE (1 << 3) /* slave data empty */
72#define SDT (1 << 2) /* slave data transmitted */
73#define SDR (1 << 1) /* slave data received */
74#define SAR (1 << 0) /* slave addr received */
75
Wolfram Sang3e3aaba2014-05-28 09:44:44 +020076/* ICMSR (also for ICMIE) */
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070077#define MNR (1 << 6) /* nack received */
78#define MAL (1 << 5) /* arbitration lost */
79#define MST (1 << 4) /* sent a stop */
80#define MDE (1 << 3)
81#define MDT (1 << 2)
82#define MDR (1 << 1)
83#define MAT (1 << 0) /* slave addr xfer done */
84
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070085
Wolfram Sang4f443a82014-05-28 09:44:38 +020086#define RCAR_BUS_PHASE_START (MDBS | MIE | ESG)
87#define RCAR_BUS_PHASE_DATA (MDBS | MIE)
88#define RCAR_BUS_PHASE_STOP (MDBS | MIE | FSB)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070089
Wolfram Sang3e3aaba2014-05-28 09:44:44 +020090#define RCAR_IRQ_SEND (MNR | MAL | MST | MAT | MDE)
91#define RCAR_IRQ_RECV (MNR | MAL | MST | MAT | MDR)
92#define RCAR_IRQ_STOP (MST)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070093
Sergei Shtylyov938916f2014-09-06 03:34:32 +040094#define RCAR_IRQ_ACK_SEND (~(MAT | MDE) & 0xFF)
95#define RCAR_IRQ_ACK_RECV (~(MAT | MDR) & 0xFF)
Wolfram Sang3c95de62014-05-28 09:44:42 +020096
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -070097#define ID_LAST_MSG (1 << 0)
98#define ID_IOERROR (1 << 1)
99#define ID_DONE (1 << 2)
100#define ID_ARBLOST (1 << 3)
101#define ID_NACK (1 << 4)
102
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900103enum rcar_i2c_type {
Kuninori Morimoto043a3f12013-10-21 01:04:32 -0700104 I2C_RCAR_GEN1,
105 I2C_RCAR_GEN2,
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900106};
107
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700108struct rcar_i2c_priv {
109 void __iomem *io;
110 struct i2c_adapter adap;
111 struct i2c_msg *msg;
Ben Dooksbc8120f2014-01-26 16:05:35 +0000112 struct clk *clk;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700113
Sergei Shtylyov91bfe292014-08-24 00:44:09 +0400114 spinlock_t lock;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700115 wait_queue_head_t wait;
116
117 int pos;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700118 u32 icccr;
119 u32 flags;
Wolfram Sang51371cd2014-05-28 09:44:45 +0200120 enum rcar_i2c_type devtype;
Wolfram Sangde20d182014-11-18 17:04:55 +0100121 struct i2c_client *slave;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700122};
123
124#define rcar_i2c_priv_to_dev(p) ((p)->adap.dev.parent)
125#define rcar_i2c_is_recv(p) ((p)->msg->flags & I2C_M_RD)
126
127#define rcar_i2c_flags_set(p, f) ((p)->flags |= (f))
128#define rcar_i2c_flags_has(p, f) ((p)->flags & (f))
129
130#define LOOP_TIMEOUT 1024
131
Wolfram Sang51371cd2014-05-28 09:44:45 +0200132
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700133static void rcar_i2c_write(struct rcar_i2c_priv *priv, int reg, u32 val)
134{
135 writel(val, priv->io + reg);
136}
137
138static u32 rcar_i2c_read(struct rcar_i2c_priv *priv, int reg)
139{
140 return readl(priv->io + reg);
141}
142
143static void rcar_i2c_init(struct rcar_i2c_priv *priv)
144{
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700145 /* reset master mode */
146 rcar_i2c_write(priv, ICMIER, 0);
Wolfram Sang93c659d2015-09-03 22:20:05 +0200147 rcar_i2c_write(priv, ICMCR, MDBS);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700148 rcar_i2c_write(priv, ICMSR, 0);
Wolfram Sang93c659d2015-09-03 22:20:05 +0200149 /* start clock */
150 rcar_i2c_write(priv, ICCCR, priv->icccr);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700151}
152
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700153static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
154{
155 int i;
156
157 for (i = 0; i < LOOP_TIMEOUT; i++) {
158 /* make sure that bus is not busy */
159 if (!(rcar_i2c_read(priv, ICMCR) & FSDA))
160 return 0;
161 udelay(1);
162 }
163
164 return -EBUSY;
165}
166
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700167static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv,
168 u32 bus_speed,
169 struct device *dev)
170{
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700171 u32 scgd, cdf;
172 u32 round, ick;
173 u32 scl;
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900174 u32 cdf_width;
Guennadi Liakhovetski8d049402013-09-12 14:36:45 +0200175 unsigned long rate;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700176
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900177 switch (priv->devtype) {
Kuninori Morimoto043a3f12013-10-21 01:04:32 -0700178 case I2C_RCAR_GEN1:
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900179 cdf_width = 2;
180 break;
Kuninori Morimoto043a3f12013-10-21 01:04:32 -0700181 case I2C_RCAR_GEN2:
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900182 cdf_width = 3;
183 break;
184 default:
185 dev_err(dev, "device type error\n");
186 return -EIO;
187 }
188
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700189 /*
190 * calculate SCL clock
191 * see
192 * ICCCR
193 *
194 * ick = clkp / (1 + CDF)
195 * SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
196 *
197 * ick : I2C internal clock < 20 MHz
198 * ticf : I2C SCL falling time = 35 ns here
199 * tr : I2C SCL rising time = 200 ns here
200 * intd : LSI internal delay = 50 ns here
201 * clkp : peripheral_clk
202 * F[] : integer up-valuation
203 */
Ben Dooksbc8120f2014-01-26 16:05:35 +0000204 rate = clk_get_rate(priv->clk);
Guennadi Liakhovetski8d049402013-09-12 14:36:45 +0200205 cdf = rate / 20000000;
Wolfram Sang22762cc2014-09-20 12:07:37 +0200206 if (cdf >= 1U << cdf_width) {
Guennadi Liakhovetski8d049402013-09-12 14:36:45 +0200207 dev_err(dev, "Input clock %lu too high\n", rate);
208 return -EIO;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700209 }
Guennadi Liakhovetski8d049402013-09-12 14:36:45 +0200210 ick = rate / (cdf + 1);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700211
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700212 /*
213 * it is impossible to calculate large scale
214 * number on u32. separate it
215 *
216 * F[(ticf + tr + intd) * ick]
217 * = F[(35 + 200 + 50)ns * ick]
218 * = F[285 * ick / 1000000000]
219 * = F[(ick / 1000000) * 285 / 1000]
220 */
221 round = (ick + 500000) / 1000000 * 285;
222 round = (round + 500) / 1000;
223
224 /*
225 * SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
226 *
227 * Calculation result (= SCL) should be less than
228 * bus_speed for hardware safety
Guennadi Liakhovetski8d049402013-09-12 14:36:45 +0200229 *
230 * We could use something along the lines of
231 * div = ick / (bus_speed + 1) + 1;
232 * scgd = (div - 20 - round + 7) / 8;
233 * scl = ick / (20 + (scgd * 8) + round);
234 * (not fully verified) but that would get pretty involved
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700235 */
236 for (scgd = 0; scgd < 0x40; scgd++) {
237 scl = ick / (20 + (scgd * 8) + round);
238 if (scl <= bus_speed)
239 goto scgd_find;
240 }
241 dev_err(dev, "it is impossible to calculate best SCL\n");
242 return -EIO;
243
244scgd_find:
245 dev_dbg(dev, "clk %d/%d(%lu), round %u, CDF:0x%x, SCGD: 0x%x\n",
Ben Dooksbc8120f2014-01-26 16:05:35 +0000246 scl, bus_speed, clk_get_rate(priv->clk), round, cdf, scgd);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700247
248 /*
249 * keep icccr value
250 */
Guennadi Liakhovetski14d32f12013-09-12 14:36:44 +0200251 priv->icccr = scgd << cdf_width | cdf;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700252
253 return 0;
254}
255
Sergei Shtylyov7c7117f2014-09-15 00:15:46 +0400256static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700257{
Wolfram Sang386babf2014-05-28 09:44:41 +0200258 int read = !!rcar_i2c_is_recv(priv);
259
260 rcar_i2c_write(priv, ICMAR, (priv->msg->addr << 1) | read);
Wolfram Sang3c95de62014-05-28 09:44:42 +0200261 rcar_i2c_write(priv, ICMSR, 0);
Wolfram Sang4f443a82014-05-28 09:44:38 +0200262 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START);
Wolfram Sang386babf2014-05-28 09:44:41 +0200263 rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700264}
265
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700266/*
267 * interrupt functions
268 */
269static int rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
270{
271 struct i2c_msg *msg = priv->msg;
272
273 /*
274 * FIXME
275 * sometimes, unknown interrupt happened.
276 * Do nothing
277 */
278 if (!(msr & MDE))
279 return 0;
280
281 /*
282 * If address transfer phase finished,
283 * goto data phase.
284 */
285 if (msr & MAT)
Wolfram Sang4f443a82014-05-28 09:44:38 +0200286 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700287
288 if (priv->pos < msg->len) {
289 /*
290 * Prepare next data to ICRXTX register.
291 * This data will go to _SHIFT_ register.
292 *
293 * *
294 * [ICRXTX] -> [SHIFT] -> [I2C bus]
295 */
296 rcar_i2c_write(priv, ICRXTX, msg->buf[priv->pos]);
297 priv->pos++;
298
299 } else {
300 /*
301 * The last data was pushed to ICRXTX on _PREV_ empty irq.
302 * It is on _SHIFT_ register, and will sent to I2C bus.
303 *
304 * *
305 * [ICRXTX] -> [SHIFT] -> [I2C bus]
306 */
307
308 if (priv->flags & ID_LAST_MSG)
309 /*
310 * If current msg is the _LAST_ msg,
311 * prepare stop condition here.
312 * ID_DONE will be set on STOP irq.
313 */
Wolfram Sang4f443a82014-05-28 09:44:38 +0200314 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700315 else
316 /*
317 * If current msg is _NOT_ last msg,
318 * it doesn't call stop phase.
319 * thus, there is no STOP irq.
320 * return ID_DONE here.
321 */
322 return ID_DONE;
323 }
324
Wolfram Sang3c95de62014-05-28 09:44:42 +0200325 rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_SEND);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700326
327 return 0;
328}
329
330static int rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
331{
332 struct i2c_msg *msg = priv->msg;
333
334 /*
335 * FIXME
336 * sometimes, unknown interrupt happened.
337 * Do nothing
338 */
339 if (!(msr & MDR))
340 return 0;
341
342 if (msr & MAT) {
343 /*
344 * Address transfer phase finished,
345 * but, there is no data at this point.
346 * Do nothing.
347 */
348 } else if (priv->pos < msg->len) {
349 /*
350 * get received data
351 */
352 msg->buf[priv->pos] = rcar_i2c_read(priv, ICRXTX);
353 priv->pos++;
354 }
355
356 /*
357 * If next received data is the _LAST_,
358 * go to STOP phase,
359 * otherwise, go to DATA phase.
360 */
361 if (priv->pos + 1 >= msg->len)
Wolfram Sang4f443a82014-05-28 09:44:38 +0200362 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700363 else
Wolfram Sang4f443a82014-05-28 09:44:38 +0200364 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700365
Wolfram Sang3c95de62014-05-28 09:44:42 +0200366 rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_RECV);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700367
368 return 0;
369}
370
Wolfram Sangde20d182014-11-18 17:04:55 +0100371static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)
372{
373 u32 ssr_raw, ssr_filtered;
374 u8 value;
375
376 ssr_raw = rcar_i2c_read(priv, ICSSR) & 0xff;
377 ssr_filtered = ssr_raw & rcar_i2c_read(priv, ICSIER);
378
379 if (!ssr_filtered)
380 return false;
381
382 /* address detected */
383 if (ssr_filtered & SAR) {
384 /* read or write request */
385 if (ssr_raw & STM) {
Wolfram Sang5b77d162015-03-23 09:26:36 +0100386 i2c_slave_event(priv->slave, I2C_SLAVE_READ_REQUESTED, &value);
Wolfram Sangde20d182014-11-18 17:04:55 +0100387 rcar_i2c_write(priv, ICRXTX, value);
388 rcar_i2c_write(priv, ICSIER, SDE | SSR | SAR);
389 } else {
Wolfram Sang5b77d162015-03-23 09:26:36 +0100390 i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
Wolfram Sangde20d182014-11-18 17:04:55 +0100391 rcar_i2c_read(priv, ICRXTX); /* dummy read */
392 rcar_i2c_write(priv, ICSIER, SDR | SSR | SAR);
393 }
394
395 rcar_i2c_write(priv, ICSSR, ~SAR & 0xff);
396 }
397
398 /* master sent stop */
399 if (ssr_filtered & SSR) {
400 i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value);
401 rcar_i2c_write(priv, ICSIER, SAR | SSR);
402 rcar_i2c_write(priv, ICSSR, ~SSR & 0xff);
403 }
404
405 /* master wants to write to us */
406 if (ssr_filtered & SDR) {
407 int ret;
408
409 value = rcar_i2c_read(priv, ICRXTX);
Wolfram Sang5b77d162015-03-23 09:26:36 +0100410 ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
Wolfram Sangde20d182014-11-18 17:04:55 +0100411 /* Send NACK in case of error */
412 rcar_i2c_write(priv, ICSCR, SIE | SDBS | (ret < 0 ? FNA : 0));
Wolfram Sangde20d182014-11-18 17:04:55 +0100413 rcar_i2c_write(priv, ICSSR, ~SDR & 0xff);
414 }
415
416 /* master wants to read from us */
417 if (ssr_filtered & SDE) {
Wolfram Sang5b77d162015-03-23 09:26:36 +0100418 i2c_slave_event(priv->slave, I2C_SLAVE_READ_PROCESSED, &value);
Wolfram Sangde20d182014-11-18 17:04:55 +0100419 rcar_i2c_write(priv, ICRXTX, value);
420 rcar_i2c_write(priv, ICSSR, ~SDE & 0xff);
421 }
422
423 return true;
424}
425
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700426static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
427{
428 struct rcar_i2c_priv *priv = ptr;
Sergei Shtylyovaa5beaf2014-09-15 00:20:19 +0400429 irqreturn_t result = IRQ_HANDLED;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700430 u32 msr;
431
Sergei Shtylyov91bfe292014-08-24 00:44:09 +0400432 /*-------------- spin lock -----------------*/
433 spin_lock(&priv->lock);
434
Wolfram Sangde20d182014-11-18 17:04:55 +0100435 if (rcar_i2c_slave_irq(priv))
436 goto exit;
437
Wolfram Sang1c176d52014-05-28 09:44:36 +0200438 msr = rcar_i2c_read(priv, ICMSR);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700439
Sergei Shtylyovdd318b02014-09-02 01:15:26 +0400440 /* Only handle interrupts that are currently enabled */
441 msr &= rcar_i2c_read(priv, ICMIER);
Sergei Shtylyovaa5beaf2014-09-15 00:20:19 +0400442 if (!msr) {
443 result = IRQ_NONE;
444 goto exit;
445 }
Sergei Shtylyovdd318b02014-09-02 01:15:26 +0400446
Wolfram Sang51371cd2014-05-28 09:44:45 +0200447 /* Arbitration lost */
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700448 if (msr & MAL) {
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700449 rcar_i2c_flags_set(priv, (ID_DONE | ID_ARBLOST));
450 goto out;
451 }
452
Wolfram Sang51371cd2014-05-28 09:44:45 +0200453 /* Nack */
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700454 if (msr & MNR) {
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700455 /* go to stop phase */
Wolfram Sang4f443a82014-05-28 09:44:38 +0200456 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
Wolfram Sangf2382242014-05-28 09:44:39 +0200457 rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700458 rcar_i2c_flags_set(priv, ID_NACK);
459 goto out;
460 }
461
Sergei Shtylyovdd318b02014-09-02 01:15:26 +0400462 /* Stop */
463 if (msr & MST) {
464 rcar_i2c_flags_set(priv, ID_DONE);
465 goto out;
466 }
467
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700468 if (rcar_i2c_is_recv(priv))
469 rcar_i2c_flags_set(priv, rcar_i2c_irq_recv(priv, msr));
470 else
471 rcar_i2c_flags_set(priv, rcar_i2c_irq_send(priv, msr));
472
473out:
474 if (rcar_i2c_flags_has(priv, ID_DONE)) {
Wolfram Sangf2382242014-05-28 09:44:39 +0200475 rcar_i2c_write(priv, ICMIER, 0);
Wolfram Sang3c95de62014-05-28 09:44:42 +0200476 rcar_i2c_write(priv, ICMSR, 0);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700477 wake_up(&priv->wait);
478 }
479
Sergei Shtylyovaa5beaf2014-09-15 00:20:19 +0400480exit:
Sergei Shtylyov91bfe292014-08-24 00:44:09 +0400481 spin_unlock(&priv->lock);
482 /*-------------- spin unlock -----------------*/
483
Sergei Shtylyovaa5beaf2014-09-15 00:20:19 +0400484 return result;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700485}
486
487static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
488 struct i2c_msg *msgs,
489 int num)
490{
491 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
492 struct device *dev = rcar_i2c_priv_to_dev(priv);
Sergei Shtylyov91bfe292014-08-24 00:44:09 +0400493 unsigned long flags;
Wolfram Sangb6763d02015-06-20 21:03:20 +0200494 int i, ret;
495 long timeout;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700496
497 pm_runtime_get_sync(dev);
498
Wolfram Sang3f7de222014-05-28 09:44:40 +0200499 ret = rcar_i2c_bus_barrier(priv);
500 if (ret < 0)
501 goto out;
502
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700503 for (i = 0; i < num; i++) {
Wolfram Sangd7653962014-05-05 18:36:21 +0200504 /* This HW can't send STOP after address phase */
505 if (msgs[i].len == 0) {
506 ret = -EOPNOTSUPP;
507 break;
508 }
509
Sergei Shtylyov91bfe292014-08-24 00:44:09 +0400510 /*-------------- spin lock -----------------*/
511 spin_lock_irqsave(&priv->lock, flags);
512
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700513 /* init each data */
514 priv->msg = &msgs[i];
515 priv->pos = 0;
516 priv->flags = 0;
Sergei Shtylyovc30d7662014-09-15 00:14:14 +0400517 if (i == num - 1)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700518 rcar_i2c_flags_set(priv, ID_LAST_MSG);
519
Sergei Shtylyov7c7117f2014-09-15 00:15:46 +0400520 rcar_i2c_prepare_msg(priv);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700521
Sergei Shtylyov91bfe292014-08-24 00:44:09 +0400522 spin_unlock_irqrestore(&priv->lock, flags);
523 /*-------------- spin unlock -----------------*/
524
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700525 timeout = wait_event_timeout(priv->wait,
526 rcar_i2c_flags_has(priv, ID_DONE),
Wolfram Sangefd2c612015-06-20 21:03:19 +0200527 adap->timeout);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700528 if (!timeout) {
529 ret = -ETIMEDOUT;
530 break;
531 }
532
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700533 if (rcar_i2c_flags_has(priv, ID_NACK)) {
Ben Dooks6ff4b1052014-01-26 16:05:37 +0000534 ret = -ENXIO;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700535 break;
536 }
537
538 if (rcar_i2c_flags_has(priv, ID_ARBLOST)) {
539 ret = -EAGAIN;
540 break;
541 }
542
543 if (rcar_i2c_flags_has(priv, ID_IOERROR)) {
544 ret = -EIO;
545 break;
546 }
547
548 ret = i + 1; /* The number of transfer */
549 }
Wolfram Sang3f7de222014-05-28 09:44:40 +0200550out:
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700551 pm_runtime_put(dev);
552
Ben Dooks6ff4b1052014-01-26 16:05:37 +0000553 if (ret < 0 && ret != -ENXIO)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700554 dev_err(dev, "error %d : %x\n", ret, priv->flags);
555
556 return ret;
557}
558
Wolfram Sangde20d182014-11-18 17:04:55 +0100559static int rcar_reg_slave(struct i2c_client *slave)
560{
561 struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter);
562
563 if (priv->slave)
564 return -EBUSY;
565
566 if (slave->flags & I2C_CLIENT_TEN)
567 return -EAFNOSUPPORT;
568
569 pm_runtime_forbid(rcar_i2c_priv_to_dev(priv));
570
571 priv->slave = slave;
572 rcar_i2c_write(priv, ICSAR, slave->addr);
573 rcar_i2c_write(priv, ICSSR, 0);
574 rcar_i2c_write(priv, ICSIER, SAR | SSR);
575 rcar_i2c_write(priv, ICSCR, SIE | SDBS);
576
577 return 0;
578}
579
580static int rcar_unreg_slave(struct i2c_client *slave)
581{
582 struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter);
583
584 WARN_ON(!priv->slave);
585
586 rcar_i2c_write(priv, ICSIER, 0);
587 rcar_i2c_write(priv, ICSCR, 0);
588
589 priv->slave = NULL;
590
591 pm_runtime_allow(rcar_i2c_priv_to_dev(priv));
592
593 return 0;
594}
595
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700596static u32 rcar_i2c_func(struct i2c_adapter *adap)
597{
Wolfram Sangd7653962014-05-05 18:36:21 +0200598 /* This HW can't do SMBUS_QUICK and NOSTART */
Wolfram Sang1fb2ad92015-05-14 14:40:03 +0200599 return I2C_FUNC_I2C | I2C_FUNC_SLAVE |
600 (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700601}
602
603static const struct i2c_algorithm rcar_i2c_algo = {
604 .master_xfer = rcar_i2c_master_xfer,
605 .functionality = rcar_i2c_func,
Wolfram Sangde20d182014-11-18 17:04:55 +0100606 .reg_slave = rcar_reg_slave,
607 .unreg_slave = rcar_unreg_slave,
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700608};
609
Guennadi Liakhovetski7679c0e2013-09-12 14:36:46 +0200610static const struct of_device_id rcar_i2c_dt_ids[] = {
Kuninori Morimoto043a3f12013-10-21 01:04:32 -0700611 { .compatible = "renesas,i2c-rcar", .data = (void *)I2C_RCAR_GEN1 },
612 { .compatible = "renesas,i2c-r8a7778", .data = (void *)I2C_RCAR_GEN1 },
613 { .compatible = "renesas,i2c-r8a7779", .data = (void *)I2C_RCAR_GEN1 },
614 { .compatible = "renesas,i2c-r8a7790", .data = (void *)I2C_RCAR_GEN2 },
Wolfram Sange8936452014-02-20 09:03:20 +0100615 { .compatible = "renesas,i2c-r8a7791", .data = (void *)I2C_RCAR_GEN2 },
Wolfram Sang819a3952014-05-27 14:06:28 +0200616 { .compatible = "renesas,i2c-r8a7792", .data = (void *)I2C_RCAR_GEN2 },
617 { .compatible = "renesas,i2c-r8a7793", .data = (void *)I2C_RCAR_GEN2 },
618 { .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 },
Guennadi Liakhovetski7679c0e2013-09-12 14:36:46 +0200619 {},
620};
621MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);
622
Bill Pemberton0b255e92012-11-27 15:59:38 -0500623static int rcar_i2c_probe(struct platform_device *pdev)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700624{
Jingoo Han6d4028c2013-07-30 16:59:33 +0900625 struct i2c_rcar_platform_data *pdata = dev_get_platdata(&pdev->dev);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700626 struct rcar_i2c_priv *priv;
627 struct i2c_adapter *adap;
628 struct resource *res;
629 struct device *dev = &pdev->dev;
630 u32 bus_speed;
Wolfram Sang93e953d2014-05-28 09:44:37 +0200631 int irq, ret;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700632
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700633 priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL);
Jingoo Han46797a22014-05-13 10:51:58 +0900634 if (!priv)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700635 return -ENOMEM;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700636
Ben Dooksbc8120f2014-01-26 16:05:35 +0000637 priv->clk = devm_clk_get(dev, NULL);
638 if (IS_ERR(priv->clk)) {
639 dev_err(dev, "cannot get clock\n");
640 return PTR_ERR(priv->clk);
641 }
642
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700643 bus_speed = 100000; /* default 100 kHz */
Guennadi Liakhovetski7679c0e2013-09-12 14:36:46 +0200644 ret = of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
645 if (ret < 0 && pdata && pdata->bus_speed)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700646 bus_speed = pdata->bus_speed;
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900647
Guennadi Liakhovetski7679c0e2013-09-12 14:36:46 +0200648 if (pdev->dev.of_node)
649 priv->devtype = (long)of_match_device(rcar_i2c_dt_ids,
650 dev)->data;
651 else
652 priv->devtype = platform_get_device_id(pdev)->driver_data;
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900653
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700654 ret = rcar_i2c_clock_calculate(priv, bus_speed, dev);
655 if (ret < 0)
656 return ret;
657
Wolfram Sang3cc2d002013-05-10 10:16:54 +0200658 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
Thierry Reding84dbf802013-01-21 11:09:03 +0100659 priv->io = devm_ioremap_resource(dev, res);
660 if (IS_ERR(priv->io))
661 return PTR_ERR(priv->io);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700662
Wolfram Sang93c659d2015-09-03 22:20:05 +0200663 rcar_i2c_init(priv);
664
Wolfram Sang93e953d2014-05-28 09:44:37 +0200665 irq = platform_get_irq(pdev, 0);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700666 init_waitqueue_head(&priv->wait);
Sergei Shtylyov91bfe292014-08-24 00:44:09 +0400667 spin_lock_init(&priv->lock);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700668
Wolfram Sang929e3aba2014-07-10 13:46:31 +0200669 adap = &priv->adap;
670 adap->nr = pdev->id;
671 adap->algo = &rcar_i2c_algo;
672 adap->class = I2C_CLASS_DEPRECATED;
673 adap->retries = 3;
674 adap->dev.parent = dev;
675 adap->dev.of_node = dev->of_node;
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700676 i2c_set_adapdata(adap, priv);
677 strlcpy(adap->name, pdev->name, sizeof(adap->name));
678
Wolfram Sang93e953d2014-05-28 09:44:37 +0200679 ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0,
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700680 dev_name(dev), priv);
681 if (ret < 0) {
Wolfram Sang93e953d2014-05-28 09:44:37 +0200682 dev_err(dev, "cannot get irq %d\n", irq);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700683 return ret;
684 }
685
686 ret = i2c_add_numbered_adapter(adap);
687 if (ret < 0) {
688 dev_err(dev, "reg adap failed: %d\n", ret);
689 return ret;
690 }
691
692 pm_runtime_enable(dev);
693 platform_set_drvdata(pdev, priv);
694
695 dev_info(dev, "probed\n");
696
697 return 0;
698}
699
Bill Pemberton0b255e92012-11-27 15:59:38 -0500700static int rcar_i2c_remove(struct platform_device *pdev)
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700701{
702 struct rcar_i2c_priv *priv = platform_get_drvdata(pdev);
703 struct device *dev = &pdev->dev;
704
705 i2c_del_adapter(&priv->adap);
706 pm_runtime_disable(dev);
707
708 return 0;
709}
710
Krzysztof Kozlowskie9a02a32015-05-02 00:54:25 +0900711static const struct platform_device_id rcar_i2c_id_table[] = {
Kuninori Morimoto043a3f12013-10-21 01:04:32 -0700712 { "i2c-rcar", I2C_RCAR_GEN1 },
713 { "i2c-rcar_gen1", I2C_RCAR_GEN1 },
714 { "i2c-rcar_gen2", I2C_RCAR_GEN2 },
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900715 {},
716};
717MODULE_DEVICE_TABLE(platform, rcar_i2c_id_table);
718
Wolfram Sang45fd5e42012-11-13 11:24:15 +0100719static struct platform_driver rcar_i2c_driver = {
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700720 .driver = {
721 .name = "i2c-rcar",
Guennadi Liakhovetski7679c0e2013-09-12 14:36:46 +0200722 .of_match_table = rcar_i2c_dt_ids,
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700723 },
724 .probe = rcar_i2c_probe,
Bill Pemberton0b255e92012-11-27 15:59:38 -0500725 .remove = rcar_i2c_remove,
Nguyen Viet Dungb7204232013-09-03 09:09:25 +0900726 .id_table = rcar_i2c_id_table,
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700727};
728
Wolfram Sang45fd5e42012-11-13 11:24:15 +0100729module_platform_driver(rcar_i2c_driver);
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700730
Wolfram Sang3d99bea2014-05-28 09:44:46 +0200731MODULE_LICENSE("GPL v2");
Kuninori Morimoto6ccbe602012-09-27 23:44:25 -0700732MODULE_DESCRIPTION("Renesas R-Car I2C bus driver");
733MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");