1 /*
2 * Driver for the Conexant CX25821 PCIe bridge
3 *
4 * Copyright (C) 2009 Conexant Systems Inc.
5 * Authors <shu.lin@conexant.com>, <hiep.huynh@conexant.com>
6 * Based on Steven Toth <stoth@linuxtv.org> cx23885 driver
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 *
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 */
23
24 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
25
26 #include "cx25821.h"
27 #include <linux/i2c.h>
28
29 static unsigned int i2c_debug;
30 module_param(i2c_debug, int, 0644);
31 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
32
33 static unsigned int i2c_scan;
34 module_param(i2c_scan, int, 0444);
35 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
36
37 #define dprintk(level, fmt, arg...) \
38 do { \
39 if (i2c_debug >= level) \
40 printk(KERN_DEBUG "%s/0: " fmt, dev->name, ##arg); \
41 } while (0)
42
43 #define I2C_WAIT_DELAY 32
44 #define I2C_WAIT_RETRY 64
45
46 #define I2C_EXTEND (1 << 3)
47 #define I2C_NOSTOP (1 << 4)
48
i2c_slave_did_ack(struct i2c_adapter * i2c_adap)49 static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
50 {
51 struct cx25821_i2c *bus = i2c_adap->algo_data;
52 struct cx25821_dev *dev = bus->dev;
53 return cx_read(bus->reg_stat) & 0x01;
54 }
55
i2c_is_busy(struct i2c_adapter * i2c_adap)56 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
57 {
58 struct cx25821_i2c *bus = i2c_adap->algo_data;
59 struct cx25821_dev *dev = bus->dev;
60 return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
61 }
62
i2c_wait_done(struct i2c_adapter * i2c_adap)63 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
64 {
65 int count;
66
67 for (count = 0; count < I2C_WAIT_RETRY; count++) {
68 if (!i2c_is_busy(i2c_adap))
69 break;
70 udelay(I2C_WAIT_DELAY);
71 }
72
73 if (I2C_WAIT_RETRY == count)
74 return 0;
75
76 return 1;
77 }
78
i2c_sendbytes(struct i2c_adapter * i2c_adap,const struct i2c_msg * msg,int joined_rlen)79 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
80 const struct i2c_msg *msg, int joined_rlen)
81 {
82 struct cx25821_i2c *bus = i2c_adap->algo_data;
83 struct cx25821_dev *dev = bus->dev;
84 u32 wdata, addr, ctrl;
85 int retval, cnt;
86
87 if (joined_rlen)
88 dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__,
89 msg->len, joined_rlen);
90 else
91 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
92
93 /* Deal with i2c probe functions with zero payload */
94 if (msg->len == 0) {
95 cx_write(bus->reg_addr, msg->addr << 25);
96 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
97
98 if (!i2c_wait_done(i2c_adap))
99 return -EIO;
100
101 if (!i2c_slave_did_ack(i2c_adap))
102 return -EIO;
103
104 dprintk(1, "%s(): returns 0\n", __func__);
105 return 0;
106 }
107
108 /* dev, reg + first byte */
109 addr = (msg->addr << 25) | msg->buf[0];
110 wdata = msg->buf[0];
111
112 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
113
114 if (msg->len > 1)
115 ctrl |= I2C_NOSTOP | I2C_EXTEND;
116 else if (joined_rlen)
117 ctrl |= I2C_NOSTOP;
118
119 cx_write(bus->reg_addr, addr);
120 cx_write(bus->reg_wdata, wdata);
121 cx_write(bus->reg_ctrl, ctrl);
122
123 retval = i2c_wait_done(i2c_adap);
124 if (retval < 0)
125 goto err;
126
127 if (retval == 0)
128 goto eio;
129
130 if (i2c_debug) {
131 if (!(ctrl & I2C_NOSTOP))
132 printk(" >\n");
133 }
134
135 for (cnt = 1; cnt < msg->len; cnt++) {
136 /* following bytes */
137 wdata = msg->buf[cnt];
138 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
139
140 if (cnt < msg->len - 1)
141 ctrl |= I2C_NOSTOP | I2C_EXTEND;
142 else if (joined_rlen)
143 ctrl |= I2C_NOSTOP;
144
145 cx_write(bus->reg_addr, addr);
146 cx_write(bus->reg_wdata, wdata);
147 cx_write(bus->reg_ctrl, ctrl);
148
149 retval = i2c_wait_done(i2c_adap);
150 if (retval < 0)
151 goto err;
152
153 if (retval == 0)
154 goto eio;
155
156 if (i2c_debug) {
157 dprintk(1, " %02x", msg->buf[cnt]);
158 if (!(ctrl & I2C_NOSTOP))
159 dprintk(1, " >\n");
160 }
161 }
162
163 return msg->len;
164
165 eio:
166 retval = -EIO;
167 err:
168 if (i2c_debug)
169 pr_err(" ERR: %d\n", retval);
170 return retval;
171 }
172
i2c_readbytes(struct i2c_adapter * i2c_adap,const struct i2c_msg * msg,int joined)173 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
174 const struct i2c_msg *msg, int joined)
175 {
176 struct cx25821_i2c *bus = i2c_adap->algo_data;
177 struct cx25821_dev *dev = bus->dev;
178 u32 ctrl, cnt;
179 int retval;
180
181 if (i2c_debug && !joined)
182 dprintk(1, "6-%s(msg->len=%d)\n", __func__, msg->len);
183
184 /* Deal with i2c probe functions with zero payload */
185 if (msg->len == 0) {
186 cx_write(bus->reg_addr, msg->addr << 25);
187 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
188 if (!i2c_wait_done(i2c_adap))
189 return -EIO;
190 if (!i2c_slave_did_ack(i2c_adap))
191 return -EIO;
192
193 dprintk(1, "%s(): returns 0\n", __func__);
194 return 0;
195 }
196
197 if (i2c_debug) {
198 if (joined)
199 dprintk(1, " R");
200 else
201 dprintk(1, " <R %02x", (msg->addr << 1) + 1);
202 }
203
204 for (cnt = 0; cnt < msg->len; cnt++) {
205
206 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
207
208 if (cnt < msg->len - 1)
209 ctrl |= I2C_NOSTOP | I2C_EXTEND;
210
211 cx_write(bus->reg_addr, msg->addr << 25);
212 cx_write(bus->reg_ctrl, ctrl);
213
214 retval = i2c_wait_done(i2c_adap);
215 if (retval < 0)
216 goto err;
217 if (retval == 0)
218 goto eio;
219 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
220
221 if (i2c_debug) {
222 dprintk(1, " %02x", msg->buf[cnt]);
223 if (!(ctrl & I2C_NOSTOP))
224 dprintk(1, " >\n");
225 }
226 }
227
228 return msg->len;
229 eio:
230 retval = -EIO;
231 err:
232 if (i2c_debug)
233 pr_err(" ERR: %d\n", retval);
234 return retval;
235 }
236
i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)237 static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
238 {
239 struct cx25821_i2c *bus = i2c_adap->algo_data;
240 struct cx25821_dev *dev = bus->dev;
241 int i, retval = 0;
242
243 dprintk(1, "%s(num = %d)\n", __func__, num);
244
245 for (i = 0; i < num; i++) {
246 dprintk(1, "%s(num = %d) addr = 0x%02x len = 0x%x\n",
247 __func__, num, msgs[i].addr, msgs[i].len);
248
249 if (msgs[i].flags & I2C_M_RD) {
250 /* read */
251 retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
252 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
253 msgs[i].addr == msgs[i + 1].addr) {
254 /* write then read from same address */
255 retval =
256 i2c_sendbytes(i2c_adap, &msgs[i], msgs[i + 1].len);
257
258 if (retval < 0)
259 goto err;
260 i++;
261 retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
262 } else {
263 /* write */
264 retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
265 }
266
267 if (retval < 0)
268 goto err;
269 }
270 return num;
271
272 err:
273 return retval;
274 }
275
276
cx25821_functionality(struct i2c_adapter * adap)277 static u32 cx25821_functionality(struct i2c_adapter *adap)
278 {
279 return I2C_FUNC_SMBUS_EMUL |
280 I2C_FUNC_I2C |
281 I2C_FUNC_SMBUS_WORD_DATA |
282 I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA;
283 }
284
285 static struct i2c_algorithm cx25821_i2c_algo_template = {
286 .master_xfer = i2c_xfer,
287 .functionality = cx25821_functionality,
288 #ifdef NEED_ALGO_CONTROL
289 .algo_control = dummy_algo_control,
290 #endif
291 };
292
293 static struct i2c_adapter cx25821_i2c_adap_template = {
294 .name = "cx25821",
295 .owner = THIS_MODULE,
296 .algo = &cx25821_i2c_algo_template,
297 };
298
299 static struct i2c_client cx25821_i2c_client_template = {
300 .name = "cx25821 internal",
301 };
302
303 /* init + register i2c algo-bit adapter */
cx25821_i2c_register(struct cx25821_i2c * bus)304 int cx25821_i2c_register(struct cx25821_i2c *bus)
305 {
306 struct cx25821_dev *dev = bus->dev;
307
308 dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
309
310 memcpy(&bus->i2c_adap, &cx25821_i2c_adap_template,
311 sizeof(bus->i2c_adap));
312 memcpy(&bus->i2c_algo, &cx25821_i2c_algo_template,
313 sizeof(bus->i2c_algo));
314 memcpy(&bus->i2c_client, &cx25821_i2c_client_template,
315 sizeof(bus->i2c_client));
316
317 bus->i2c_adap.dev.parent = &dev->pci->dev;
318
319 strlcpy(bus->i2c_adap.name, bus->dev->name, sizeof(bus->i2c_adap.name));
320
321 bus->i2c_algo.data = bus;
322 bus->i2c_adap.algo_data = bus;
323 i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
324 i2c_add_adapter(&bus->i2c_adap);
325
326 bus->i2c_client.adapter = &bus->i2c_adap;
327
328 /* set up the I2c */
329 bus->i2c_client.addr = (0x88 >> 1);
330
331 return bus->i2c_rc;
332 }
333
cx25821_i2c_unregister(struct cx25821_i2c * bus)334 int cx25821_i2c_unregister(struct cx25821_i2c *bus)
335 {
336 i2c_del_adapter(&bus->i2c_adap);
337 return 0;
338 }
339
cx25821_av_clk(struct cx25821_dev * dev,int enable)340 void cx25821_av_clk(struct cx25821_dev *dev, int enable)
341 {
342 /* write 0 to bus 2 addr 0x144 via i2x_xfer() */
343 char buffer[3];
344 struct i2c_msg msg;
345 dprintk(1, "%s(enabled = %d)\n", __func__, enable);
346
347 /* Register 0x144 */
348 buffer[0] = 0x01;
349 buffer[1] = 0x44;
350 if (enable == 1)
351 buffer[2] = 0x05;
352 else
353 buffer[2] = 0x00;
354
355 msg.addr = 0x44;
356 msg.flags = I2C_M_TEN;
357 msg.len = 3;
358 msg.buf = buffer;
359
360 i2c_xfer(&dev->i2c_bus[0].i2c_adap, &msg, 1);
361 }
362
cx25821_i2c_read(struct cx25821_i2c * bus,u16 reg_addr,int * value)363 int cx25821_i2c_read(struct cx25821_i2c *bus, u16 reg_addr, int *value)
364 {
365 struct i2c_client *client = &bus->i2c_client;
366 int retval = 0;
367 int v = 0;
368 u8 addr[2] = { 0, 0 };
369 u8 buf[4] = { 0, 0, 0, 0 };
370
371 struct i2c_msg msgs[2] = {
372 {
373 .addr = client->addr,
374 .flags = 0,
375 .len = 2,
376 .buf = addr,
377 }, {
378 .addr = client->addr,
379 .flags = I2C_M_RD,
380 .len = 4,
381 .buf = buf,
382 }
383 };
384
385 addr[0] = (reg_addr >> 8);
386 addr[1] = (reg_addr & 0xff);
387 msgs[0].addr = 0x44;
388 msgs[1].addr = 0x44;
389
390 retval = i2c_xfer(client->adapter, msgs, 2);
391
392 v = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
393 *value = v;
394
395 return v;
396 }
397
cx25821_i2c_write(struct cx25821_i2c * bus,u16 reg_addr,int value)398 int cx25821_i2c_write(struct cx25821_i2c *bus, u16 reg_addr, int value)
399 {
400 struct i2c_client *client = &bus->i2c_client;
401 int retval = 0;
402 u8 buf[6] = { 0, 0, 0, 0, 0, 0 };
403
404 struct i2c_msg msgs[1] = {
405 {
406 .addr = client->addr,
407 .flags = 0,
408 .len = 6,
409 .buf = buf,
410 }
411 };
412
413 buf[0] = reg_addr >> 8;
414 buf[1] = reg_addr & 0xff;
415 buf[5] = (value >> 24) & 0xff;
416 buf[4] = (value >> 16) & 0xff;
417 buf[3] = (value >> 8) & 0xff;
418 buf[2] = value & 0xff;
419 client->flags = 0;
420 msgs[0].addr = 0x44;
421
422 retval = i2c_xfer(client->adapter, msgs, 1);
423
424 return retval;
425 }
426