Commit | Line | Data |
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95a7f10e VB |
1 | /* |
2 | * TI DAVINCI I2C adapter driver. | |
3 | * | |
4 | * Copyright (C) 2006 Texas Instruments. | |
5 | * Copyright (C) 2007 MontaVista Software Inc. | |
6 | * | |
7 | * Updated by Vinod & Sudhakar Feb 2005 | |
8 | * | |
9 | * ---------------------------------------------------------------------------- | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2 of the License, or | |
14 | * (at your option) any later version. | |
15 | * | |
16 | * This program is distributed in the hope that it will be useful, | |
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
19 | * GNU General Public License for more details. | |
20 | * | |
21 | * You should have received a copy of the GNU General Public License | |
22 | * along with this program; if not, write to the Free Software | |
23 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
24 | * ---------------------------------------------------------------------------- | |
25 | * | |
26 | */ | |
27 | #include <linux/kernel.h> | |
28 | #include <linux/module.h> | |
29 | #include <linux/delay.h> | |
30 | #include <linux/i2c.h> | |
31 | #include <linux/clk.h> | |
32 | #include <linux/errno.h> | |
33 | #include <linux/sched.h> | |
34 | #include <linux/err.h> | |
35 | #include <linux/interrupt.h> | |
36 | #include <linux/platform_device.h> | |
37 | #include <linux/io.h> | |
5a0e3ad6 | 38 | #include <linux/slab.h> |
82c0de11 | 39 | #include <linux/cpufreq.h> |
95a7f10e | 40 | |
a09e64fb | 41 | #include <mach/hardware.h> |
a09e64fb | 42 | #include <mach/i2c.h> |
95a7f10e VB |
43 | |
44 | /* ----- global defines ----------------------------------------------- */ | |
45 | ||
46 | #define DAVINCI_I2C_TIMEOUT (1*HZ) | |
47 | #define I2C_DAVINCI_INTR_ALL (DAVINCI_I2C_IMR_AAS | \ | |
48 | DAVINCI_I2C_IMR_SCD | \ | |
49 | DAVINCI_I2C_IMR_ARDY | \ | |
50 | DAVINCI_I2C_IMR_NACK | \ | |
51 | DAVINCI_I2C_IMR_AL) | |
52 | ||
53 | #define DAVINCI_I2C_OAR_REG 0x00 | |
54 | #define DAVINCI_I2C_IMR_REG 0x04 | |
55 | #define DAVINCI_I2C_STR_REG 0x08 | |
56 | #define DAVINCI_I2C_CLKL_REG 0x0c | |
57 | #define DAVINCI_I2C_CLKH_REG 0x10 | |
58 | #define DAVINCI_I2C_CNT_REG 0x14 | |
59 | #define DAVINCI_I2C_DRR_REG 0x18 | |
60 | #define DAVINCI_I2C_SAR_REG 0x1c | |
61 | #define DAVINCI_I2C_DXR_REG 0x20 | |
62 | #define DAVINCI_I2C_MDR_REG 0x24 | |
63 | #define DAVINCI_I2C_IVR_REG 0x28 | |
64 | #define DAVINCI_I2C_EMDR_REG 0x2c | |
65 | #define DAVINCI_I2C_PSC_REG 0x30 | |
66 | ||
67 | #define DAVINCI_I2C_IVR_AAS 0x07 | |
68 | #define DAVINCI_I2C_IVR_SCD 0x06 | |
69 | #define DAVINCI_I2C_IVR_XRDY 0x05 | |
70 | #define DAVINCI_I2C_IVR_RDR 0x04 | |
71 | #define DAVINCI_I2C_IVR_ARDY 0x03 | |
72 | #define DAVINCI_I2C_IVR_NACK 0x02 | |
73 | #define DAVINCI_I2C_IVR_AL 0x01 | |
74 | ||
c062a251 C |
75 | #define DAVINCI_I2C_STR_BB BIT(12) |
76 | #define DAVINCI_I2C_STR_RSFULL BIT(11) | |
77 | #define DAVINCI_I2C_STR_SCD BIT(5) | |
78 | #define DAVINCI_I2C_STR_ARDY BIT(2) | |
79 | #define DAVINCI_I2C_STR_NACK BIT(1) | |
80 | #define DAVINCI_I2C_STR_AL BIT(0) | |
81 | ||
82 | #define DAVINCI_I2C_MDR_NACK BIT(15) | |
83 | #define DAVINCI_I2C_MDR_STT BIT(13) | |
84 | #define DAVINCI_I2C_MDR_STP BIT(11) | |
85 | #define DAVINCI_I2C_MDR_MST BIT(10) | |
86 | #define DAVINCI_I2C_MDR_TRX BIT(9) | |
87 | #define DAVINCI_I2C_MDR_XA BIT(8) | |
88 | #define DAVINCI_I2C_MDR_RM BIT(7) | |
89 | #define DAVINCI_I2C_MDR_IRS BIT(5) | |
90 | ||
91 | #define DAVINCI_I2C_IMR_AAS BIT(6) | |
92 | #define DAVINCI_I2C_IMR_SCD BIT(5) | |
93 | #define DAVINCI_I2C_IMR_XRDY BIT(4) | |
94 | #define DAVINCI_I2C_IMR_RRDY BIT(3) | |
95 | #define DAVINCI_I2C_IMR_ARDY BIT(2) | |
96 | #define DAVINCI_I2C_IMR_NACK BIT(1) | |
97 | #define DAVINCI_I2C_IMR_AL BIT(0) | |
95a7f10e VB |
98 | |
99 | struct davinci_i2c_dev { | |
100 | struct device *dev; | |
101 | void __iomem *base; | |
102 | struct completion cmd_complete; | |
103 | struct clk *clk; | |
104 | int cmd_err; | |
105 | u8 *buf; | |
106 | size_t buf_len; | |
107 | int irq; | |
c6c7c729 | 108 | int stop; |
5a0d5f5f | 109 | u8 terminate; |
95a7f10e | 110 | struct i2c_adapter adapter; |
82c0de11 C |
111 | #ifdef CONFIG_CPU_FREQ |
112 | struct completion xfr_complete; | |
113 | struct notifier_block freq_transition; | |
114 | #endif | |
95a7f10e VB |
115 | }; |
116 | ||
117 | /* default platform data to use if not supplied in the platform_device */ | |
118 | static struct davinci_i2c_platform_data davinci_i2c_platform_data_default = { | |
119 | .bus_freq = 100, | |
120 | .bus_delay = 0, | |
121 | }; | |
122 | ||
123 | static inline void davinci_i2c_write_reg(struct davinci_i2c_dev *i2c_dev, | |
124 | int reg, u16 val) | |
125 | { | |
126 | __raw_writew(val, i2c_dev->base + reg); | |
127 | } | |
128 | ||
129 | static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg) | |
130 | { | |
131 | return __raw_readw(i2c_dev->base + reg); | |
132 | } | |
133 | ||
5ae5b113 C |
134 | static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev, |
135 | int val) | |
136 | { | |
137 | u16 w; | |
138 | ||
139 | w = davinci_i2c_read_reg(i2c_dev, DAVINCI_I2C_MDR_REG); | |
140 | if (!val) /* put I2C into reset */ | |
141 | w &= ~DAVINCI_I2C_MDR_IRS; | |
142 | else /* take I2C out of reset */ | |
143 | w |= DAVINCI_I2C_MDR_IRS; | |
144 | ||
145 | davinci_i2c_write_reg(i2c_dev, DAVINCI_I2C_MDR_REG, w); | |
146 | } | |
147 | ||
148 | static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev) | |
95a7f10e VB |
149 | { |
150 | struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; | |
151 | u16 psc; | |
152 | u32 clk; | |
cc99ff70 | 153 | u32 d; |
95a7f10e VB |
154 | u32 clkh; |
155 | u32 clkl; | |
156 | u32 input_clock = clk_get_rate(dev->clk); | |
95a7f10e VB |
157 | |
158 | /* NOTE: I2C Clock divider programming info | |
159 | * As per I2C specs the following formulas provide prescaler | |
160 | * and low/high divider values | |
161 | * input clk --> PSC Div -----------> ICCL/H Div --> output clock | |
162 | * module clk | |
163 | * | |
164 | * output clk = module clk / (PSC + 1) [ (ICCL + d) + (ICCH + d) ] | |
165 | * | |
166 | * Thus, | |
167 | * (ICCL + ICCH) = clk = (input clk / ((psc +1) * output clk)) - 2d; | |
168 | * | |
169 | * where if PSC == 0, d = 7, | |
170 | * if PSC == 1, d = 6 | |
171 | * if PSC > 1 , d = 5 | |
172 | */ | |
173 | ||
cc99ff70 TK |
174 | /* get minimum of 7 MHz clock, but max of 12 MHz */ |
175 | psc = (input_clock / 7000000) - 1; | |
176 | if ((input_clock / (psc + 1)) > 12000000) | |
177 | psc++; /* better to run under spec than over */ | |
178 | d = (psc >= 2) ? 5 : 7 - psc; | |
95a7f10e | 179 | |
cc99ff70 TK |
180 | clk = ((input_clock / (psc + 1)) / (pdata->bus_freq * 1000)) - (d << 1); |
181 | clkh = clk >> 1; | |
95a7f10e VB |
182 | clkl = clk - clkh; |
183 | ||
184 | davinci_i2c_write_reg(dev, DAVINCI_I2C_PSC_REG, psc); | |
185 | davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKH_REG, clkh); | |
186 | davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKL_REG, clkl); | |
187 | ||
5ae5b113 C |
188 | dev_dbg(dev->dev, "input_clock = %d, CLK = %d\n", input_clock, clk); |
189 | } | |
190 | ||
191 | /* | |
192 | * This function configures I2C and brings I2C out of reset. | |
193 | * This function is called during I2C init function. This function | |
194 | * also gets called if I2C encounters any errors. | |
195 | */ | |
196 | static int i2c_davinci_init(struct davinci_i2c_dev *dev) | |
197 | { | |
198 | struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; | |
199 | ||
200 | if (!pdata) | |
201 | pdata = &davinci_i2c_platform_data_default; | |
202 | ||
203 | /* put I2C into reset */ | |
204 | davinci_i2c_reset_ctrl(dev, 0); | |
205 | ||
206 | /* compute clock dividers */ | |
207 | i2c_davinci_calc_clk_dividers(dev); | |
208 | ||
7605fa3b DB |
209 | /* Respond at reserved "SMBus Host" slave address" (and zero); |
210 | * we seem to have no option to not respond... | |
211 | */ | |
212 | davinci_i2c_write_reg(dev, DAVINCI_I2C_OAR_REG, 0x08); | |
213 | ||
95a7f10e VB |
214 | dev_dbg(dev->dev, "PSC = %d\n", |
215 | davinci_i2c_read_reg(dev, DAVINCI_I2C_PSC_REG)); | |
216 | dev_dbg(dev->dev, "CLKL = %d\n", | |
217 | davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKL_REG)); | |
218 | dev_dbg(dev->dev, "CLKH = %d\n", | |
219 | davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKH_REG)); | |
cc99ff70 TK |
220 | dev_dbg(dev->dev, "bus_freq = %dkHz, bus_delay = %d\n", |
221 | pdata->bus_freq, pdata->bus_delay); | |
95a7f10e VB |
222 | |
223 | /* Take the I2C module out of reset: */ | |
5ae5b113 | 224 | davinci_i2c_reset_ctrl(dev, 1); |
95a7f10e VB |
225 | |
226 | /* Enable interrupts */ | |
227 | davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, I2C_DAVINCI_INTR_ALL); | |
228 | ||
229 | return 0; | |
230 | } | |
231 | ||
232 | /* | |
233 | * Waiting for bus not busy | |
234 | */ | |
235 | static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev, | |
236 | char allow_sleep) | |
237 | { | |
238 | unsigned long timeout; | |
239 | ||
98a679ca | 240 | timeout = jiffies + dev->adapter.timeout; |
95a7f10e VB |
241 | while (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) |
242 | & DAVINCI_I2C_STR_BB) { | |
243 | if (time_after(jiffies, timeout)) { | |
244 | dev_warn(dev->dev, | |
245 | "timeout waiting for bus ready\n"); | |
246 | return -ETIMEDOUT; | |
247 | } | |
248 | if (allow_sleep) | |
249 | schedule_timeout(1); | |
250 | } | |
251 | ||
252 | return 0; | |
253 | } | |
254 | ||
255 | /* | |
256 | * Low level master read/write transaction. This function is called | |
257 | * from i2c_davinci_xfer. | |
258 | */ | |
259 | static int | |
260 | i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop) | |
261 | { | |
262 | struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); | |
263 | struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; | |
264 | u32 flag; | |
95a7f10e VB |
265 | u16 w; |
266 | int r; | |
267 | ||
95a7f10e VB |
268 | if (!pdata) |
269 | pdata = &davinci_i2c_platform_data_default; | |
270 | /* Introduce a delay, required for some boards (e.g Davinci EVM) */ | |
271 | if (pdata->bus_delay) | |
272 | udelay(pdata->bus_delay); | |
273 | ||
274 | /* set the slave address */ | |
275 | davinci_i2c_write_reg(dev, DAVINCI_I2C_SAR_REG, msg->addr); | |
276 | ||
277 | dev->buf = msg->buf; | |
278 | dev->buf_len = msg->len; | |
c6c7c729 | 279 | dev->stop = stop; |
95a7f10e VB |
280 | |
281 | davinci_i2c_write_reg(dev, DAVINCI_I2C_CNT_REG, dev->buf_len); | |
282 | ||
2e743787 | 283 | INIT_COMPLETION(dev->cmd_complete); |
95a7f10e VB |
284 | dev->cmd_err = 0; |
285 | ||
95a7f10e VB |
286 | /* Take I2C out of reset, configure it as master and set the |
287 | * start bit */ | |
288 | flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST | DAVINCI_I2C_MDR_STT; | |
289 | ||
290 | /* if the slave address is ten bit address, enable XA bit */ | |
291 | if (msg->flags & I2C_M_TEN) | |
292 | flag |= DAVINCI_I2C_MDR_XA; | |
293 | if (!(msg->flags & I2C_M_RD)) | |
294 | flag |= DAVINCI_I2C_MDR_TRX; | |
295 | if (stop) | |
296 | flag |= DAVINCI_I2C_MDR_STP; | |
c6c7c729 DB |
297 | if (msg->len == 0) { |
298 | flag |= DAVINCI_I2C_MDR_RM; | |
299 | flag &= ~DAVINCI_I2C_MDR_STP; | |
300 | } | |
95a7f10e VB |
301 | |
302 | /* Enable receive or transmit interrupts */ | |
303 | w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG); | |
304 | if (msg->flags & I2C_M_RD) | |
c062a251 | 305 | w |= DAVINCI_I2C_IMR_RRDY; |
95a7f10e | 306 | else |
c062a251 | 307 | w |= DAVINCI_I2C_IMR_XRDY; |
95a7f10e VB |
308 | davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w); |
309 | ||
5a0d5f5f | 310 | dev->terminate = 0; |
c6c7c729 | 311 | |
95a7f10e VB |
312 | /* write the data into mode register */ |
313 | davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); | |
314 | ||
c6c7c729 DB |
315 | /* |
316 | * First byte should be set here, not after interrupt, | |
317 | * because transmit-data-ready interrupt can come before | |
318 | * NACK-interrupt during sending of previous message and | |
319 | * ICDXR may have wrong data | |
320 | */ | |
321 | if ((!(msg->flags & I2C_M_RD)) && dev->buf_len) { | |
322 | davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++); | |
323 | dev->buf_len--; | |
324 | } | |
325 | ||
95a7f10e | 326 | r = wait_for_completion_interruptible_timeout(&dev->cmd_complete, |
98a679ca | 327 | dev->adapter.timeout); |
95a7f10e VB |
328 | if (r == 0) { |
329 | dev_err(dev->dev, "controller timed out\n"); | |
330 | i2c_davinci_init(dev); | |
5a0d5f5f | 331 | dev->buf_len = 0; |
95a7f10e VB |
332 | return -ETIMEDOUT; |
333 | } | |
5a0d5f5f TK |
334 | if (dev->buf_len) { |
335 | /* This should be 0 if all bytes were transferred | |
336 | * or dev->cmd_err denotes an error. | |
337 | * A signal may have aborted the transfer. | |
338 | */ | |
339 | if (r >= 0) { | |
340 | dev_err(dev->dev, "abnormal termination buf_len=%i\n", | |
341 | dev->buf_len); | |
342 | r = -EREMOTEIO; | |
343 | } | |
344 | dev->terminate = 1; | |
345 | wmb(); | |
346 | dev->buf_len = 0; | |
347 | } | |
348 | if (r < 0) | |
349 | return r; | |
95a7f10e VB |
350 | |
351 | /* no error */ | |
352 | if (likely(!dev->cmd_err)) | |
353 | return msg->len; | |
354 | ||
355 | /* We have an error */ | |
356 | if (dev->cmd_err & DAVINCI_I2C_STR_AL) { | |
357 | i2c_davinci_init(dev); | |
358 | return -EIO; | |
359 | } | |
360 | ||
361 | if (dev->cmd_err & DAVINCI_I2C_STR_NACK) { | |
362 | if (msg->flags & I2C_M_IGNORE_NAK) | |
363 | return msg->len; | |
364 | if (stop) { | |
365 | w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); | |
c062a251 | 366 | w |= DAVINCI_I2C_MDR_STP; |
95a7f10e VB |
367 | davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); |
368 | } | |
369 | return -EREMOTEIO; | |
370 | } | |
371 | return -EIO; | |
372 | } | |
373 | ||
374 | /* | |
375 | * Prepare controller for a transaction and call i2c_davinci_xfer_msg | |
376 | */ | |
377 | static int | |
378 | i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) | |
379 | { | |
380 | struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); | |
381 | int i; | |
382 | int ret; | |
383 | ||
08882d20 | 384 | dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num); |
95a7f10e VB |
385 | |
386 | ret = i2c_davinci_wait_bus_not_busy(dev, 1); | |
387 | if (ret < 0) { | |
388 | dev_warn(dev->dev, "timeout waiting for bus ready\n"); | |
389 | return ret; | |
390 | } | |
391 | ||
392 | for (i = 0; i < num; i++) { | |
393 | ret = i2c_davinci_xfer_msg(adap, &msgs[i], (i == (num - 1))); | |
d868caa1 TK |
394 | dev_dbg(dev->dev, "%s [%d/%d] ret: %d\n", __func__, i + 1, num, |
395 | ret); | |
95a7f10e VB |
396 | if (ret < 0) |
397 | return ret; | |
398 | } | |
82c0de11 C |
399 | |
400 | #ifdef CONFIG_CPU_FREQ | |
401 | complete(&dev->xfr_complete); | |
402 | #endif | |
403 | ||
95a7f10e VB |
404 | return num; |
405 | } | |
406 | ||
407 | static u32 i2c_davinci_func(struct i2c_adapter *adap) | |
408 | { | |
c6c7c729 | 409 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
95a7f10e VB |
410 | } |
411 | ||
5a0d5f5f TK |
412 | static void terminate_read(struct davinci_i2c_dev *dev) |
413 | { | |
414 | u16 w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); | |
415 | w |= DAVINCI_I2C_MDR_NACK; | |
416 | davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); | |
417 | ||
418 | /* Throw away data */ | |
419 | davinci_i2c_read_reg(dev, DAVINCI_I2C_DRR_REG); | |
420 | if (!dev->terminate) | |
421 | dev_err(dev->dev, "RDR IRQ while no data requested\n"); | |
422 | } | |
423 | static void terminate_write(struct davinci_i2c_dev *dev) | |
424 | { | |
425 | u16 w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); | |
426 | w |= DAVINCI_I2C_MDR_RM | DAVINCI_I2C_MDR_STP; | |
427 | davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); | |
428 | ||
429 | if (!dev->terminate) | |
7605fa3b | 430 | dev_dbg(dev->dev, "TDR IRQ while no data to send\n"); |
5a0d5f5f TK |
431 | } |
432 | ||
95a7f10e VB |
433 | /* |
434 | * Interrupt service routine. This gets called whenever an I2C interrupt | |
435 | * occurs. | |
436 | */ | |
437 | static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id) | |
438 | { | |
439 | struct davinci_i2c_dev *dev = dev_id; | |
440 | u32 stat; | |
441 | int count = 0; | |
442 | u16 w; | |
443 | ||
444 | while ((stat = davinci_i2c_read_reg(dev, DAVINCI_I2C_IVR_REG))) { | |
08882d20 | 445 | dev_dbg(dev->dev, "%s: stat=0x%x\n", __func__, stat); |
95a7f10e VB |
446 | if (count++ == 100) { |
447 | dev_warn(dev->dev, "Too much work in one IRQ\n"); | |
448 | break; | |
449 | } | |
450 | ||
451 | switch (stat) { | |
452 | case DAVINCI_I2C_IVR_AL: | |
5a0d5f5f | 453 | /* Arbitration lost, must retry */ |
95a7f10e | 454 | dev->cmd_err |= DAVINCI_I2C_STR_AL; |
5a0d5f5f | 455 | dev->buf_len = 0; |
95a7f10e VB |
456 | complete(&dev->cmd_complete); |
457 | break; | |
458 | ||
459 | case DAVINCI_I2C_IVR_NACK: | |
460 | dev->cmd_err |= DAVINCI_I2C_STR_NACK; | |
5a0d5f5f | 461 | dev->buf_len = 0; |
95a7f10e VB |
462 | complete(&dev->cmd_complete); |
463 | break; | |
464 | ||
465 | case DAVINCI_I2C_IVR_ARDY: | |
b73a9aec TK |
466 | davinci_i2c_write_reg(dev, |
467 | DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_ARDY); | |
c6c7c729 DB |
468 | if (((dev->buf_len == 0) && (dev->stop != 0)) || |
469 | (dev->cmd_err & DAVINCI_I2C_STR_NACK)) { | |
470 | w = davinci_i2c_read_reg(dev, | |
471 | DAVINCI_I2C_MDR_REG); | |
472 | w |= DAVINCI_I2C_MDR_STP; | |
473 | davinci_i2c_write_reg(dev, | |
474 | DAVINCI_I2C_MDR_REG, w); | |
475 | } | |
95a7f10e VB |
476 | complete(&dev->cmd_complete); |
477 | break; | |
478 | ||
479 | case DAVINCI_I2C_IVR_RDR: | |
480 | if (dev->buf_len) { | |
481 | *dev->buf++ = | |
482 | davinci_i2c_read_reg(dev, | |
483 | DAVINCI_I2C_DRR_REG); | |
484 | dev->buf_len--; | |
485 | if (dev->buf_len) | |
486 | continue; | |
487 | ||
95a7f10e | 488 | davinci_i2c_write_reg(dev, |
b73a9aec TK |
489 | DAVINCI_I2C_STR_REG, |
490 | DAVINCI_I2C_IMR_RRDY); | |
5a0d5f5f TK |
491 | } else { |
492 | /* signal can terminate transfer */ | |
493 | terminate_read(dev); | |
494 | } | |
95a7f10e VB |
495 | break; |
496 | ||
497 | case DAVINCI_I2C_IVR_XRDY: | |
498 | if (dev->buf_len) { | |
499 | davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, | |
500 | *dev->buf++); | |
501 | dev->buf_len--; | |
502 | if (dev->buf_len) | |
503 | continue; | |
504 | ||
505 | w = davinci_i2c_read_reg(dev, | |
506 | DAVINCI_I2C_IMR_REG); | |
c062a251 | 507 | w &= ~DAVINCI_I2C_IMR_XRDY; |
95a7f10e VB |
508 | davinci_i2c_write_reg(dev, |
509 | DAVINCI_I2C_IMR_REG, | |
510 | w); | |
5a0d5f5f TK |
511 | } else { |
512 | /* signal can terminate transfer */ | |
513 | terminate_write(dev); | |
514 | } | |
95a7f10e VB |
515 | break; |
516 | ||
517 | case DAVINCI_I2C_IVR_SCD: | |
b73a9aec TK |
518 | davinci_i2c_write_reg(dev, |
519 | DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_SCD); | |
95a7f10e VB |
520 | complete(&dev->cmd_complete); |
521 | break; | |
522 | ||
523 | case DAVINCI_I2C_IVR_AAS: | |
7605fa3b DB |
524 | dev_dbg(dev->dev, "Address as slave interrupt\n"); |
525 | break; | |
526 | ||
527 | default: | |
528 | dev_warn(dev->dev, "Unrecognized irq stat %d\n", stat); | |
529 | break; | |
530 | } | |
531 | } | |
95a7f10e VB |
532 | |
533 | return count ? IRQ_HANDLED : IRQ_NONE; | |
534 | } | |
535 | ||
82c0de11 C |
536 | #ifdef CONFIG_CPU_FREQ |
537 | static int i2c_davinci_cpufreq_transition(struct notifier_block *nb, | |
538 | unsigned long val, void *data) | |
539 | { | |
540 | struct davinci_i2c_dev *dev; | |
541 | ||
542 | dev = container_of(nb, struct davinci_i2c_dev, freq_transition); | |
543 | if (val == CPUFREQ_PRECHANGE) { | |
544 | wait_for_completion(&dev->xfr_complete); | |
545 | davinci_i2c_reset_ctrl(dev, 0); | |
546 | } else if (val == CPUFREQ_POSTCHANGE) { | |
547 | i2c_davinci_calc_clk_dividers(dev); | |
548 | davinci_i2c_reset_ctrl(dev, 1); | |
549 | } | |
550 | ||
551 | return 0; | |
552 | } | |
553 | ||
554 | static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) | |
555 | { | |
556 | dev->freq_transition.notifier_call = i2c_davinci_cpufreq_transition; | |
557 | ||
558 | return cpufreq_register_notifier(&dev->freq_transition, | |
559 | CPUFREQ_TRANSITION_NOTIFIER); | |
560 | } | |
561 | ||
562 | static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) | |
563 | { | |
564 | cpufreq_unregister_notifier(&dev->freq_transition, | |
565 | CPUFREQ_TRANSITION_NOTIFIER); | |
566 | } | |
567 | #else | |
568 | static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) | |
569 | { | |
570 | return 0; | |
571 | } | |
572 | ||
573 | static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) | |
574 | { | |
575 | } | |
576 | #endif | |
577 | ||
95a7f10e VB |
578 | static struct i2c_algorithm i2c_davinci_algo = { |
579 | .master_xfer = i2c_davinci_xfer, | |
580 | .functionality = i2c_davinci_func, | |
581 | }; | |
582 | ||
583 | static int davinci_i2c_probe(struct platform_device *pdev) | |
584 | { | |
585 | struct davinci_i2c_dev *dev; | |
586 | struct i2c_adapter *adap; | |
587 | struct resource *mem, *irq, *ioarea; | |
588 | int r; | |
589 | ||
590 | /* NOTE: driver uses the static register mapping */ | |
591 | mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
592 | if (!mem) { | |
593 | dev_err(&pdev->dev, "no mem resource?\n"); | |
594 | return -ENODEV; | |
595 | } | |
596 | ||
597 | irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); | |
598 | if (!irq) { | |
599 | dev_err(&pdev->dev, "no irq resource?\n"); | |
600 | return -ENODEV; | |
601 | } | |
602 | ||
59330825 | 603 | ioarea = request_mem_region(mem->start, resource_size(mem), |
95a7f10e VB |
604 | pdev->name); |
605 | if (!ioarea) { | |
606 | dev_err(&pdev->dev, "I2C region already claimed\n"); | |
607 | return -EBUSY; | |
608 | } | |
609 | ||
610 | dev = kzalloc(sizeof(struct davinci_i2c_dev), GFP_KERNEL); | |
611 | if (!dev) { | |
612 | r = -ENOMEM; | |
613 | goto err_release_region; | |
614 | } | |
615 | ||
2e743787 | 616 | init_completion(&dev->cmd_complete); |
82c0de11 C |
617 | #ifdef CONFIG_CPU_FREQ |
618 | init_completion(&dev->xfr_complete); | |
619 | #endif | |
95a7f10e VB |
620 | dev->dev = get_device(&pdev->dev); |
621 | dev->irq = irq->start; | |
622 | platform_set_drvdata(pdev, dev); | |
623 | ||
e164ddee | 624 | dev->clk = clk_get(&pdev->dev, NULL); |
95a7f10e VB |
625 | if (IS_ERR(dev->clk)) { |
626 | r = -ENODEV; | |
627 | goto err_free_mem; | |
628 | } | |
629 | clk_enable(dev->clk); | |
630 | ||
c062a251 C |
631 | dev->base = ioremap(mem->start, resource_size(mem)); |
632 | if (!dev->base) { | |
633 | r = -EBUSY; | |
634 | goto err_mem_ioremap; | |
635 | } | |
636 | ||
95a7f10e VB |
637 | i2c_davinci_init(dev); |
638 | ||
639 | r = request_irq(dev->irq, i2c_davinci_isr, 0, pdev->name, dev); | |
640 | if (r) { | |
641 | dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq); | |
642 | goto err_unuse_clocks; | |
643 | } | |
644 | ||
82c0de11 C |
645 | r = i2c_davinci_cpufreq_register(dev); |
646 | if (r) { | |
647 | dev_err(&pdev->dev, "failed to register cpufreq\n"); | |
648 | goto err_free_irq; | |
649 | } | |
650 | ||
95a7f10e VB |
651 | adap = &dev->adapter; |
652 | i2c_set_adapdata(adap, dev); | |
653 | adap->owner = THIS_MODULE; | |
654 | adap->class = I2C_CLASS_HWMON; | |
655 | strlcpy(adap->name, "DaVinci I2C adapter", sizeof(adap->name)); | |
656 | adap->algo = &i2c_davinci_algo; | |
657 | adap->dev.parent = &pdev->dev; | |
98a679ca | 658 | adap->timeout = DAVINCI_I2C_TIMEOUT; |
95a7f10e VB |
659 | |
660 | adap->nr = pdev->id; | |
661 | r = i2c_add_numbered_adapter(adap); | |
662 | if (r) { | |
663 | dev_err(&pdev->dev, "failure adding adapter\n"); | |
664 | goto err_free_irq; | |
665 | } | |
666 | ||
667 | return 0; | |
668 | ||
669 | err_free_irq: | |
670 | free_irq(dev->irq, dev); | |
671 | err_unuse_clocks: | |
c062a251 C |
672 | iounmap(dev->base); |
673 | err_mem_ioremap: | |
95a7f10e VB |
674 | clk_disable(dev->clk); |
675 | clk_put(dev->clk); | |
676 | dev->clk = NULL; | |
677 | err_free_mem: | |
678 | platform_set_drvdata(pdev, NULL); | |
679 | put_device(&pdev->dev); | |
680 | kfree(dev); | |
681 | err_release_region: | |
59330825 | 682 | release_mem_region(mem->start, resource_size(mem)); |
95a7f10e VB |
683 | |
684 | return r; | |
685 | } | |
686 | ||
687 | static int davinci_i2c_remove(struct platform_device *pdev) | |
688 | { | |
689 | struct davinci_i2c_dev *dev = platform_get_drvdata(pdev); | |
690 | struct resource *mem; | |
691 | ||
82c0de11 C |
692 | i2c_davinci_cpufreq_deregister(dev); |
693 | ||
95a7f10e VB |
694 | platform_set_drvdata(pdev, NULL); |
695 | i2c_del_adapter(&dev->adapter); | |
696 | put_device(&pdev->dev); | |
697 | ||
698 | clk_disable(dev->clk); | |
699 | clk_put(dev->clk); | |
700 | dev->clk = NULL; | |
701 | ||
702 | davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0); | |
703 | free_irq(IRQ_I2C, dev); | |
c062a251 | 704 | iounmap(dev->base); |
95a7f10e VB |
705 | kfree(dev); |
706 | ||
707 | mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
59330825 | 708 | release_mem_region(mem->start, resource_size(mem)); |
95a7f10e VB |
709 | return 0; |
710 | } | |
711 | ||
68f15de9 C |
712 | #ifdef CONFIG_PM |
713 | static int davinci_i2c_suspend(struct device *dev) | |
714 | { | |
715 | struct platform_device *pdev = to_platform_device(dev); | |
716 | struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | |
717 | ||
718 | /* put I2C into reset */ | |
719 | davinci_i2c_reset_ctrl(i2c_dev, 0); | |
720 | clk_disable(i2c_dev->clk); | |
721 | ||
722 | return 0; | |
723 | } | |
724 | ||
725 | static int davinci_i2c_resume(struct device *dev) | |
726 | { | |
727 | struct platform_device *pdev = to_platform_device(dev); | |
728 | struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | |
729 | ||
730 | clk_enable(i2c_dev->clk); | |
731 | /* take I2C out of reset */ | |
732 | davinci_i2c_reset_ctrl(i2c_dev, 1); | |
733 | ||
734 | return 0; | |
735 | } | |
736 | ||
737 | static const struct dev_pm_ops davinci_i2c_pm = { | |
738 | .suspend = davinci_i2c_suspend, | |
739 | .resume = davinci_i2c_resume, | |
740 | }; | |
741 | ||
742 | #define davinci_i2c_pm_ops (&davinci_i2c_pm) | |
743 | #else | |
744 | #define davinci_i2c_pm_ops NULL | |
745 | #endif | |
746 | ||
add8eda7 KS |
747 | /* work with hotplug and coldplug */ |
748 | MODULE_ALIAS("platform:i2c_davinci"); | |
749 | ||
95a7f10e VB |
750 | static struct platform_driver davinci_i2c_driver = { |
751 | .probe = davinci_i2c_probe, | |
752 | .remove = davinci_i2c_remove, | |
753 | .driver = { | |
754 | .name = "i2c_davinci", | |
755 | .owner = THIS_MODULE, | |
68f15de9 | 756 | .pm = davinci_i2c_pm_ops, |
95a7f10e VB |
757 | }, |
758 | }; | |
759 | ||
760 | /* I2C may be needed to bring up other drivers */ | |
761 | static int __init davinci_i2c_init_driver(void) | |
762 | { | |
763 | return platform_driver_register(&davinci_i2c_driver); | |
764 | } | |
765 | subsys_initcall(davinci_i2c_init_driver); | |
766 | ||
767 | static void __exit davinci_i2c_exit_driver(void) | |
768 | { | |
769 | platform_driver_unregister(&davinci_i2c_driver); | |
770 | } | |
771 | module_exit(davinci_i2c_exit_driver); | |
772 | ||
773 | MODULE_AUTHOR("Texas Instruments India"); | |
774 | MODULE_DESCRIPTION("TI DaVinci I2C bus adapter"); | |
775 | MODULE_LICENSE("GPL"); |