1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * |
4 | * device driver for philips saa7134 based TV cards |
5 | * i2c interface support |
6 | * |
7 | * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs] |
8 | */ |
9 | |
10 | #include "saa7134.h" |
11 | #include "saa7134-reg.h" |
12 | |
13 | #include <linux/init.h> |
14 | #include <linux/list.h> |
15 | #include <linux/module.h> |
16 | #include <linux/kernel.h> |
17 | #include <linux/delay.h> |
18 | |
19 | #include <media/v4l2-common.h> |
20 | |
21 | /* ----------------------------------------------------------- */ |
22 | |
23 | static unsigned int i2c_debug; |
24 | module_param(i2c_debug, int, 0644); |
25 | MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]" ); |
26 | |
27 | static unsigned int i2c_scan; |
28 | module_param(i2c_scan, int, 0444); |
29 | MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time" ); |
30 | |
31 | #define i2c_dbg(level, fmt, arg...) do { \ |
32 | if (i2c_debug == level) \ |
33 | printk(KERN_DEBUG pr_fmt("i2c: " fmt), ## arg); \ |
34 | } while (0) |
35 | |
36 | #define i2c_cont(level, fmt, arg...) do { \ |
37 | if (i2c_debug == level) \ |
38 | pr_cont(fmt, ## arg); \ |
39 | } while (0) |
40 | |
41 | #define I2C_WAIT_DELAY 32 |
42 | #define I2C_WAIT_RETRY 16 |
43 | |
44 | /* ----------------------------------------------------------- */ |
45 | |
46 | static char *str_i2c_status[] = { |
47 | "IDLE" , "DONE_STOP" , "BUSY" , "TO_SCL" , "TO_ARB" , "DONE_WRITE" , |
48 | "DONE_READ" , "DONE_WRITE_TO" , "DONE_READ_TO" , "NO_DEVICE" , |
49 | "NO_ACKN" , "BUS_ERR" , "ARB_LOST" , "SEQ_ERR" , "ST_ERR" , "SW_ERR" |
50 | }; |
51 | |
52 | enum i2c_status { |
53 | IDLE = 0, // no I2C command pending |
54 | DONE_STOP = 1, // I2C command done and STOP executed |
55 | BUSY = 2, // executing I2C command |
56 | TO_SCL = 3, // executing I2C command, time out on clock stretching |
57 | TO_ARB = 4, // time out on arbitration trial, still trying |
58 | DONE_WRITE = 5, // I2C command done and awaiting next write command |
59 | DONE_READ = 6, // I2C command done and awaiting next read command |
60 | DONE_WRITE_TO = 7, // see 5, and time out on status echo |
61 | DONE_READ_TO = 8, // see 6, and time out on status echo |
62 | NO_DEVICE = 9, // no acknowledge on device slave address |
63 | NO_ACKN = 10, // no acknowledge after data byte transfer |
64 | BUS_ERR = 11, // bus error |
65 | ARB_LOST = 12, // arbitration lost during transfer |
66 | SEQ_ERR = 13, // erroneous programming sequence |
67 | ST_ERR = 14, // wrong status echoing |
68 | SW_ERR = 15 // software error |
69 | }; |
70 | |
71 | static char *str_i2c_attr[] = { |
72 | "NOP" , "STOP" , "CONTINUE" , "START" |
73 | }; |
74 | |
75 | enum i2c_attr { |
76 | NOP = 0, // no operation on I2C bus |
77 | STOP = 1, // stop condition, no associated byte transfer |
78 | CONTINUE = 2, // continue with byte transfer |
79 | START = 3 // start condition with byte transfer |
80 | }; |
81 | |
82 | static inline enum i2c_status i2c_get_status(struct saa7134_dev *dev) |
83 | { |
84 | enum i2c_status status; |
85 | |
86 | status = saa_readb(SAA7134_I2C_ATTR_STATUS) & 0x0f; |
87 | i2c_dbg(2, "i2c stat <= %s\n" , str_i2c_status[status]); |
88 | return status; |
89 | } |
90 | |
91 | static inline void i2c_set_status(struct saa7134_dev *dev, |
92 | enum i2c_status status) |
93 | { |
94 | i2c_dbg(2, "i2c stat => %s\n" , str_i2c_status[status]); |
95 | saa_andorb(SAA7134_I2C_ATTR_STATUS,0x0f,status); |
96 | } |
97 | |
98 | static inline void i2c_set_attr(struct saa7134_dev *dev, enum i2c_attr attr) |
99 | { |
100 | i2c_dbg(2, "i2c attr => %s\n" , str_i2c_attr[attr]); |
101 | saa_andorb(SAA7134_I2C_ATTR_STATUS,0xc0,attr << 6); |
102 | } |
103 | |
104 | static inline int i2c_is_error(enum i2c_status status) |
105 | { |
106 | switch (status) { |
107 | case NO_DEVICE: |
108 | case NO_ACKN: |
109 | case BUS_ERR: |
110 | case ARB_LOST: |
111 | case SEQ_ERR: |
112 | case ST_ERR: |
113 | return true; |
114 | default: |
115 | return false; |
116 | } |
117 | } |
118 | |
119 | static inline int i2c_is_idle(enum i2c_status status) |
120 | { |
121 | switch (status) { |
122 | case IDLE: |
123 | case DONE_STOP: |
124 | return true; |
125 | default: |
126 | return false; |
127 | } |
128 | } |
129 | |
130 | static inline int i2c_is_busy(enum i2c_status status) |
131 | { |
132 | switch (status) { |
133 | case BUSY: |
134 | case TO_SCL: |
135 | case TO_ARB: |
136 | return true; |
137 | default: |
138 | return false; |
139 | } |
140 | } |
141 | |
142 | static int i2c_is_busy_wait(struct saa7134_dev *dev) |
143 | { |
144 | enum i2c_status status; |
145 | int count; |
146 | |
147 | for (count = 0; count < I2C_WAIT_RETRY; count++) { |
148 | status = i2c_get_status(dev); |
149 | if (!i2c_is_busy(status)) |
150 | break; |
151 | saa_wait(I2C_WAIT_DELAY); |
152 | } |
153 | if (I2C_WAIT_RETRY == count) |
154 | return false; |
155 | return true; |
156 | } |
157 | |
158 | static int i2c_reset(struct saa7134_dev *dev) |
159 | { |
160 | enum i2c_status status; |
161 | int count; |
162 | |
163 | i2c_dbg(2, "i2c reset\n" ); |
164 | status = i2c_get_status(dev); |
165 | if (!i2c_is_error(status)) |
166 | return true; |
167 | i2c_set_status(dev,status); |
168 | |
169 | for (count = 0; count < I2C_WAIT_RETRY; count++) { |
170 | status = i2c_get_status(dev); |
171 | if (!i2c_is_error(status)) |
172 | break; |
173 | udelay(I2C_WAIT_DELAY); |
174 | } |
175 | if (I2C_WAIT_RETRY == count) |
176 | return false; |
177 | |
178 | if (!i2c_is_idle(status)) |
179 | return false; |
180 | |
181 | i2c_set_attr(dev,attr: NOP); |
182 | return true; |
183 | } |
184 | |
185 | static inline int i2c_send_byte(struct saa7134_dev *dev, |
186 | enum i2c_attr attr, |
187 | unsigned char data) |
188 | { |
189 | enum i2c_status status; |
190 | __u32 dword; |
191 | |
192 | /* have to write both attr + data in one 32bit word */ |
193 | dword = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2); |
194 | dword &= 0x0f; |
195 | dword |= (attr << 6); |
196 | dword |= ((__u32)data << 8); |
197 | dword |= 0x00 << 16; /* 100 kHz */ |
198 | // dword |= 0x40 << 16; /* 400 kHz */ |
199 | dword |= 0xf0 << 24; |
200 | saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword); |
201 | i2c_dbg(2, "i2c data => 0x%x\n" , data); |
202 | |
203 | if (!i2c_is_busy_wait(dev)) |
204 | return -EIO; |
205 | status = i2c_get_status(dev); |
206 | if (i2c_is_error(status)) |
207 | return -EIO; |
208 | return 0; |
209 | } |
210 | |
211 | static inline int i2c_recv_byte(struct saa7134_dev *dev) |
212 | { |
213 | enum i2c_status status; |
214 | unsigned char data; |
215 | |
216 | i2c_set_attr(dev,attr: CONTINUE); |
217 | if (!i2c_is_busy_wait(dev)) |
218 | return -EIO; |
219 | status = i2c_get_status(dev); |
220 | if (i2c_is_error(status)) |
221 | return -EIO; |
222 | data = saa_readb(SAA7134_I2C_DATA); |
223 | i2c_dbg(2, "i2c data <= 0x%x\n" , data); |
224 | return data; |
225 | } |
226 | |
227 | static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap, |
228 | struct i2c_msg *msgs, int num) |
229 | { |
230 | struct saa7134_dev *dev = i2c_adap->algo_data; |
231 | enum i2c_status status; |
232 | unsigned char data; |
233 | int addr,rc,i,byte; |
234 | |
235 | status = i2c_get_status(dev); |
236 | if (!i2c_is_idle(status)) |
237 | if (!i2c_reset(dev)) |
238 | return -EIO; |
239 | |
240 | i2c_dbg(2, "start xfer\n" ); |
241 | i2c_dbg(1, "i2c xfer:" ); |
242 | for (i = 0; i < num; i++) { |
243 | if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) { |
244 | /* send address */ |
245 | i2c_dbg(2, "send address\n" ); |
246 | addr = msgs[i].addr << 1; |
247 | if (msgs[i].flags & I2C_M_RD) |
248 | addr |= 1; |
249 | if (i > 0 && msgs[i].flags & |
250 | I2C_M_RD && msgs[i].addr != 0x40 && |
251 | msgs[i].addr != 0x41 && |
252 | msgs[i].addr != 0x19) { |
253 | /* workaround for a saa7134 i2c bug |
254 | * needed to talk to the mt352 demux |
255 | * thanks to pinnacle for the hint */ |
256 | int quirk = 0xfe; |
257 | i2c_cont(1, " [%02x quirk]" , quirk); |
258 | i2c_send_byte(dev,attr: START,data: quirk); |
259 | i2c_recv_byte(dev); |
260 | } |
261 | i2c_cont(1, " < %02x" , addr); |
262 | rc = i2c_send_byte(dev,attr: START,data: addr); |
263 | if (rc < 0) |
264 | goto err; |
265 | } |
266 | if (msgs[i].flags & I2C_M_RD) { |
267 | /* read bytes */ |
268 | i2c_dbg(2, "read bytes\n" ); |
269 | for (byte = 0; byte < msgs[i].len; byte++) { |
270 | i2c_cont(1, " =" ); |
271 | rc = i2c_recv_byte(dev); |
272 | if (rc < 0) |
273 | goto err; |
274 | i2c_cont(1, "%02x" , rc); |
275 | msgs[i].buf[byte] = rc; |
276 | } |
277 | /* discard mysterious extra byte when reading |
278 | from Samsung S5H1411. i2c bus gets error |
279 | if we do not. */ |
280 | if (0x19 == msgs[i].addr) { |
281 | i2c_cont(1, " ?" ); |
282 | rc = i2c_recv_byte(dev); |
283 | if (rc < 0) |
284 | goto err; |
285 | i2c_cont(1, "%02x" , rc); |
286 | } |
287 | } else { |
288 | /* write bytes */ |
289 | i2c_dbg(2, "write bytes\n" ); |
290 | for (byte = 0; byte < msgs[i].len; byte++) { |
291 | data = msgs[i].buf[byte]; |
292 | i2c_cont(1, " %02x" , data); |
293 | rc = i2c_send_byte(dev,attr: CONTINUE,data); |
294 | if (rc < 0) |
295 | goto err; |
296 | } |
297 | } |
298 | } |
299 | i2c_dbg(2, "xfer done\n" ); |
300 | i2c_cont(1, " >" ); |
301 | i2c_set_attr(dev,attr: STOP); |
302 | rc = -EIO; |
303 | if (!i2c_is_busy_wait(dev)) |
304 | goto err; |
305 | status = i2c_get_status(dev); |
306 | if (i2c_is_error(status)) |
307 | goto err; |
308 | /* ensure that the bus is idle for at least one bit slot */ |
309 | msleep(msecs: 1); |
310 | |
311 | i2c_cont(1, "\n" ); |
312 | return num; |
313 | err: |
314 | if (1 == i2c_debug) { |
315 | status = i2c_get_status(dev); |
316 | i2c_cont(1, " ERROR: %s\n" , str_i2c_status[status]); |
317 | } |
318 | return rc; |
319 | } |
320 | |
321 | /* ----------------------------------------------------------- */ |
322 | |
323 | static u32 functionality(struct i2c_adapter *adap) |
324 | { |
325 | return I2C_FUNC_SMBUS_EMUL; |
326 | } |
327 | |
328 | static const struct i2c_algorithm saa7134_algo = { |
329 | .master_xfer = saa7134_i2c_xfer, |
330 | .functionality = functionality, |
331 | }; |
332 | |
333 | static const struct i2c_adapter saa7134_adap_template = { |
334 | .owner = THIS_MODULE, |
335 | .name = "saa7134" , |
336 | .algo = &saa7134_algo, |
337 | }; |
338 | |
339 | static const struct i2c_client saa7134_client_template = { |
340 | .name = "saa7134 internal" , |
341 | }; |
342 | |
343 | /* ----------------------------------------------------------- */ |
344 | |
345 | /* |
346 | * On Medion 7134 reading the SAA7134 chip config EEPROM needs DVB-T |
347 | * demod i2c gate closed due to an address clash between this EEPROM |
348 | * and the demod one. |
349 | */ |
350 | static void saa7134_i2c_eeprom_md7134_gate(struct saa7134_dev *dev) |
351 | { |
352 | u8 subaddr = 0x7, dmdregval; |
353 | u8 data[2]; |
354 | int ret; |
355 | struct i2c_msg i2cgatemsg_r[] = { {.addr = 0x08, .flags = 0, |
356 | .buf = &subaddr, .len = 1}, |
357 | {.addr = 0x08, |
358 | .flags = I2C_M_RD, |
359 | .buf = &dmdregval, .len = 1} |
360 | }; |
361 | struct i2c_msg i2cgatemsg_w[] = { {.addr = 0x08, .flags = 0, |
362 | .buf = data, .len = 2} }; |
363 | |
364 | ret = i2c_transfer(adap: &dev->i2c_adap, msgs: i2cgatemsg_r, num: 2); |
365 | if ((ret == 2) && (dmdregval & 0x2)) { |
366 | pr_debug("%s: DVB-T demod i2c gate was left open\n" , |
367 | dev->name); |
368 | |
369 | data[0] = subaddr; |
370 | data[1] = (dmdregval & ~0x2); |
371 | if (i2c_transfer(adap: &dev->i2c_adap, msgs: i2cgatemsg_w, num: 1) != 1) |
372 | pr_err("%s: EEPROM i2c gate close failure\n" , |
373 | dev->name); |
374 | } |
375 | } |
376 | |
377 | static int |
378 | saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len) |
379 | { |
380 | unsigned char buf; |
381 | int i,err; |
382 | |
383 | if (dev->board == SAA7134_BOARD_MD7134) |
384 | saa7134_i2c_eeprom_md7134_gate(dev); |
385 | |
386 | dev->i2c_client.addr = 0xa0 >> 1; |
387 | buf = 0; |
388 | if (1 != (err = i2c_master_send(client: &dev->i2c_client,buf: &buf,count: 1))) { |
389 | pr_info("%s: Huh, no eeprom present (err=%d)?\n" , |
390 | dev->name,err); |
391 | return -1; |
392 | } |
393 | if (len != (err = i2c_master_recv(client: &dev->i2c_client,buf: eedata,count: len))) { |
394 | pr_warn("%s: i2c eeprom read error (err=%d)\n" , |
395 | dev->name,err); |
396 | return -1; |
397 | } |
398 | |
399 | for (i = 0; i < len; i += 16) { |
400 | int size = (len - i) > 16 ? 16 : len - i; |
401 | |
402 | pr_info("i2c eeprom %02x: %*ph\n" , i, size, &eedata[i]); |
403 | } |
404 | |
405 | return 0; |
406 | } |
407 | |
408 | static char *i2c_devs[128] = { |
409 | [ 0x20 ] = "mpeg encoder (saa6752hs)" , |
410 | [ 0xa0 >> 1 ] = "eeprom" , |
411 | [ 0xc0 >> 1 ] = "tuner (analog)" , |
412 | [ 0x86 >> 1 ] = "tda9887" , |
413 | [ 0x5a >> 1 ] = "remote control" , |
414 | }; |
415 | |
416 | static void do_i2c_scan(struct i2c_client *c) |
417 | { |
418 | unsigned char buf; |
419 | int i,rc; |
420 | |
421 | for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) { |
422 | c->addr = i; |
423 | rc = i2c_master_recv(client: c,buf: &buf,count: 0); |
424 | if (rc < 0) |
425 | continue; |
426 | pr_info("i2c scan: found device @ 0x%x [%s]\n" , |
427 | i << 1, i2c_devs[i] ? i2c_devs[i] : "???" ); |
428 | } |
429 | } |
430 | |
431 | int saa7134_i2c_register(struct saa7134_dev *dev) |
432 | { |
433 | dev->i2c_adap = saa7134_adap_template; |
434 | dev->i2c_adap.dev.parent = &dev->pci->dev; |
435 | strscpy(dev->i2c_adap.name, dev->name, sizeof(dev->i2c_adap.name)); |
436 | dev->i2c_adap.algo_data = dev; |
437 | i2c_set_adapdata(adap: &dev->i2c_adap, data: &dev->v4l2_dev); |
438 | i2c_add_adapter(adap: &dev->i2c_adap); |
439 | |
440 | dev->i2c_client = saa7134_client_template; |
441 | dev->i2c_client.adapter = &dev->i2c_adap; |
442 | |
443 | saa7134_i2c_eeprom(dev,eedata: dev->eedata,len: sizeof(dev->eedata)); |
444 | if (i2c_scan) |
445 | do_i2c_scan(c: &dev->i2c_client); |
446 | |
447 | /* Instantiate the IR receiver device, if present */ |
448 | saa7134_probe_i2c_ir(dev); |
449 | return 0; |
450 | } |
451 | |
452 | int saa7134_i2c_unregister(struct saa7134_dev *dev) |
453 | { |
454 | i2c_del_adapter(adap: &dev->i2c_adap); |
455 | return 0; |
456 | } |
457 | |