1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | |
4 | bttv-i2c.c -- all the i2c code is here |
5 | |
6 | bttv - Bt848 frame grabber driver |
7 | |
8 | Copyright (C) 1996,97,98 Ralph Metzler (rjkm@thp.uni-koeln.de) |
9 | & Marcus Metzler (mocm@thp.uni-koeln.de) |
10 | (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org> |
11 | |
12 | (c) 2005 Mauro Carvalho Chehab <mchehab@kernel.org> |
13 | - Multituner support and i2c address binding |
14 | |
15 | |
16 | */ |
17 | |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | |
20 | #include <linux/module.h> |
21 | #include <linux/init.h> |
22 | #include <linux/delay.h> |
23 | |
24 | #include "bttvp.h" |
25 | #include <media/v4l2-common.h> |
26 | #include <linux/jiffies.h> |
27 | #include <asm/io.h> |
28 | |
29 | static int i2c_debug; |
30 | static int i2c_hw; |
31 | static int i2c_scan; |
32 | module_param(i2c_debug, int, 0644); |
33 | MODULE_PARM_DESC(i2c_debug, "configure i2c debug level" ); |
34 | module_param(i2c_hw, int, 0444); |
35 | MODULE_PARM_DESC(i2c_hw, "force use of hardware i2c support, instead of software bitbang" ); |
36 | module_param(i2c_scan, int, 0444); |
37 | MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time" ); |
38 | |
39 | static unsigned int i2c_udelay = 5; |
40 | module_param(i2c_udelay, int, 0444); |
41 | MODULE_PARM_DESC(i2c_udelay, "soft i2c delay at insmod time, in usecs (should be 5 or higher). Lower value means higher bus speed." ); |
42 | |
43 | /* ----------------------------------------------------------------------- */ |
44 | /* I2C functions - bitbanging adapter (software i2c) */ |
45 | |
46 | static void bttv_bit_setscl(void *data, int state) |
47 | { |
48 | struct bttv *btv = (struct bttv*)data; |
49 | |
50 | if (state) |
51 | btv->i2c_state |= 0x02; |
52 | else |
53 | btv->i2c_state &= ~0x02; |
54 | btwrite(btv->i2c_state, BT848_I2C); |
55 | btread(BT848_I2C); |
56 | } |
57 | |
58 | static void bttv_bit_setsda(void *data, int state) |
59 | { |
60 | struct bttv *btv = (struct bttv*)data; |
61 | |
62 | if (state) |
63 | btv->i2c_state |= 0x01; |
64 | else |
65 | btv->i2c_state &= ~0x01; |
66 | btwrite(btv->i2c_state, BT848_I2C); |
67 | btread(BT848_I2C); |
68 | } |
69 | |
70 | static int bttv_bit_getscl(void *data) |
71 | { |
72 | struct bttv *btv = (struct bttv*)data; |
73 | int state; |
74 | |
75 | state = btread(BT848_I2C) & 0x02 ? 1 : 0; |
76 | return state; |
77 | } |
78 | |
79 | static int bttv_bit_getsda(void *data) |
80 | { |
81 | struct bttv *btv = (struct bttv*)data; |
82 | int state; |
83 | |
84 | state = btread(BT848_I2C) & 0x01; |
85 | return state; |
86 | } |
87 | |
88 | static const struct i2c_algo_bit_data bttv_i2c_algo_bit_template = { |
89 | .setsda = bttv_bit_setsda, |
90 | .setscl = bttv_bit_setscl, |
91 | .getsda = bttv_bit_getsda, |
92 | .getscl = bttv_bit_getscl, |
93 | .udelay = 16, |
94 | .timeout = 200, |
95 | }; |
96 | |
97 | /* ----------------------------------------------------------------------- */ |
98 | /* I2C functions - hardware i2c */ |
99 | |
100 | static u32 functionality(struct i2c_adapter *adap) |
101 | { |
102 | return I2C_FUNC_SMBUS_EMUL; |
103 | } |
104 | |
105 | static int |
106 | bttv_i2c_wait_done(struct bttv *btv) |
107 | { |
108 | int rc = 0; |
109 | |
110 | /* timeout */ |
111 | if (wait_event_interruptible_timeout(btv->i2c_queue, |
112 | btv->i2c_done, msecs_to_jiffies(85)) == -ERESTARTSYS) |
113 | rc = -EIO; |
114 | |
115 | if (btv->i2c_done & BT848_INT_RACK) |
116 | rc = 1; |
117 | btv->i2c_done = 0; |
118 | return rc; |
119 | } |
120 | |
121 | #define I2C_HW (BT878_I2C_MODE | BT848_I2C_SYNC |\ |
122 | BT848_I2C_SCL | BT848_I2C_SDA) |
123 | |
124 | static int |
125 | bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last) |
126 | { |
127 | u32 xmit; |
128 | int retval,cnt; |
129 | |
130 | /* sanity checks */ |
131 | if (0 == msg->len) |
132 | return -EINVAL; |
133 | |
134 | /* start, address + first byte */ |
135 | xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW; |
136 | if (msg->len > 1 || !last) |
137 | xmit |= BT878_I2C_NOSTOP; |
138 | btwrite(xmit, BT848_I2C); |
139 | retval = bttv_i2c_wait_done(btv); |
140 | if (retval < 0) |
141 | goto err; |
142 | if (retval == 0) |
143 | goto eio; |
144 | if (i2c_debug) { |
145 | pr_cont(" <W %02x %02x" , msg->addr << 1, msg->buf[0]); |
146 | } |
147 | |
148 | for (cnt = 1; cnt < msg->len; cnt++ ) { |
149 | /* following bytes */ |
150 | xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART; |
151 | if (cnt < msg->len-1 || !last) |
152 | xmit |= BT878_I2C_NOSTOP; |
153 | btwrite(xmit, BT848_I2C); |
154 | retval = bttv_i2c_wait_done(btv); |
155 | if (retval < 0) |
156 | goto err; |
157 | if (retval == 0) |
158 | goto eio; |
159 | if (i2c_debug) |
160 | pr_cont(" %02x" , msg->buf[cnt]); |
161 | } |
162 | if (i2c_debug && !(xmit & BT878_I2C_NOSTOP)) |
163 | pr_cont(">\n" ); |
164 | return msg->len; |
165 | |
166 | eio: |
167 | retval = -EIO; |
168 | err: |
169 | if (i2c_debug) |
170 | pr_cont(" ERR: %d\n" ,retval); |
171 | return retval; |
172 | } |
173 | |
174 | static int |
175 | bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last) |
176 | { |
177 | u32 xmit; |
178 | u32 cnt; |
179 | int retval; |
180 | |
181 | for (cnt = 0; cnt < msg->len; cnt++) { |
182 | xmit = (msg->addr << 25) | (1 << 24) | I2C_HW; |
183 | if (cnt < msg->len-1) |
184 | xmit |= BT848_I2C_W3B; |
185 | if (cnt < msg->len-1 || !last) |
186 | xmit |= BT878_I2C_NOSTOP; |
187 | if (cnt) |
188 | xmit |= BT878_I2C_NOSTART; |
189 | |
190 | if (i2c_debug) { |
191 | if (!(xmit & BT878_I2C_NOSTART)) |
192 | pr_cont(" <R %02x" , (msg->addr << 1) +1); |
193 | } |
194 | |
195 | btwrite(xmit, BT848_I2C); |
196 | retval = bttv_i2c_wait_done(btv); |
197 | if (retval < 0) |
198 | goto err; |
199 | if (retval == 0) |
200 | goto eio; |
201 | msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff; |
202 | if (i2c_debug) { |
203 | pr_cont(" =%02x" , msg->buf[cnt]); |
204 | } |
205 | if (i2c_debug && !(xmit & BT878_I2C_NOSTOP)) |
206 | pr_cont(" >\n" ); |
207 | } |
208 | |
209 | |
210 | return msg->len; |
211 | |
212 | eio: |
213 | retval = -EIO; |
214 | err: |
215 | if (i2c_debug) |
216 | pr_cont(" ERR: %d\n" ,retval); |
217 | return retval; |
218 | } |
219 | |
220 | static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num) |
221 | { |
222 | struct v4l2_device *v4l2_dev = i2c_get_adapdata(adap: i2c_adap); |
223 | struct bttv *btv = to_bttv(v4l2_dev); |
224 | int retval = 0; |
225 | int i; |
226 | |
227 | if (i2c_debug) |
228 | pr_debug("bt-i2c:" ); |
229 | |
230 | btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT); |
231 | for (i = 0 ; i < num; i++) { |
232 | if (msgs[i].flags & I2C_M_RD) { |
233 | /* read */ |
234 | retval = bttv_i2c_readbytes(btv, msg: &msgs[i], last: i+1 == num); |
235 | if (retval < 0) |
236 | goto err; |
237 | } else { |
238 | /* write */ |
239 | retval = bttv_i2c_sendbytes(btv, msg: &msgs[i], last: i+1 == num); |
240 | if (retval < 0) |
241 | goto err; |
242 | } |
243 | } |
244 | return num; |
245 | |
246 | err: |
247 | return retval; |
248 | } |
249 | |
250 | static const struct i2c_algorithm bttv_algo = { |
251 | .master_xfer = bttv_i2c_xfer, |
252 | .functionality = functionality, |
253 | }; |
254 | |
255 | /* ----------------------------------------------------------------------- */ |
256 | /* I2C functions - common stuff */ |
257 | |
258 | /* read I2C */ |
259 | int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for) |
260 | { |
261 | unsigned char buffer = 0; |
262 | |
263 | if (0 != btv->i2c_rc) |
264 | return -1; |
265 | if (bttv_verbose && NULL != probe_for) |
266 | pr_info("%d: i2c: checking for %s @ 0x%02x... " , |
267 | btv->c.nr, probe_for, addr); |
268 | btv->i2c_client.addr = addr >> 1; |
269 | if (1 != i2c_master_recv(client: &btv->i2c_client, buf: &buffer, count: 1)) { |
270 | if (NULL != probe_for) { |
271 | if (bttv_verbose) |
272 | pr_cont("not found\n" ); |
273 | } else |
274 | pr_warn("%d: i2c read 0x%x: error\n" , |
275 | btv->c.nr, addr); |
276 | return -1; |
277 | } |
278 | if (bttv_verbose && NULL != probe_for) |
279 | pr_cont("found\n" ); |
280 | return buffer; |
281 | } |
282 | |
283 | /* write I2C */ |
284 | int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1, |
285 | unsigned char b2, int both) |
286 | { |
287 | unsigned char buffer[2]; |
288 | int bytes = both ? 2 : 1; |
289 | |
290 | if (0 != btv->i2c_rc) |
291 | return -1; |
292 | btv->i2c_client.addr = addr >> 1; |
293 | buffer[0] = b1; |
294 | buffer[1] = b2; |
295 | if (bytes != i2c_master_send(client: &btv->i2c_client, buf: buffer, count: bytes)) |
296 | return -1; |
297 | return 0; |
298 | } |
299 | |
300 | /* read EEPROM content */ |
301 | void bttv_readee(struct bttv *btv, unsigned char *eedata, int addr) |
302 | { |
303 | memset(eedata, 0, 256); |
304 | if (0 != btv->i2c_rc) |
305 | return; |
306 | btv->i2c_client.addr = addr >> 1; |
307 | tveeprom_read(c: &btv->i2c_client, eedata, len: 256); |
308 | } |
309 | |
310 | static char *i2c_devs[128] = { |
311 | [ 0x1c >> 1 ] = "lgdt330x" , |
312 | [ 0x30 >> 1 ] = "IR (hauppauge)" , |
313 | [ 0x80 >> 1 ] = "msp34xx" , |
314 | [ 0x86 >> 1 ] = "tda9887" , |
315 | [ 0xa0 >> 1 ] = "eeprom" , |
316 | [ 0xc0 >> 1 ] = "tuner (analog)" , |
317 | [ 0xc2 >> 1 ] = "tuner (analog)" , |
318 | }; |
319 | |
320 | static void do_i2c_scan(char *name, struct i2c_client *c) |
321 | { |
322 | unsigned char buf; |
323 | int i,rc; |
324 | |
325 | for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) { |
326 | c->addr = i; |
327 | rc = i2c_master_recv(client: c,buf: &buf,count: 0); |
328 | if (rc < 0) |
329 | continue; |
330 | pr_info("%s: i2c scan: found device @ 0x%x [%s]\n" , |
331 | name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???" ); |
332 | } |
333 | } |
334 | |
335 | /* init + register i2c adapter */ |
336 | int init_bttv_i2c(struct bttv *btv) |
337 | { |
338 | strscpy(btv->i2c_client.name, "bttv internal" , I2C_NAME_SIZE); |
339 | |
340 | if (i2c_hw) |
341 | btv->use_i2c_hw = 1; |
342 | if (btv->use_i2c_hw) { |
343 | /* bt878 */ |
344 | strscpy(btv->c.i2c_adap.name, "bt878" , |
345 | sizeof(btv->c.i2c_adap.name)); |
346 | btv->c.i2c_adap.algo = &bttv_algo; |
347 | } else { |
348 | /* bt848 */ |
349 | /* Prevents usage of invalid delay values */ |
350 | if (i2c_udelay<5) |
351 | i2c_udelay=5; |
352 | |
353 | strscpy(btv->c.i2c_adap.name, "bttv" , |
354 | sizeof(btv->c.i2c_adap.name)); |
355 | btv->i2c_algo = bttv_i2c_algo_bit_template; |
356 | btv->i2c_algo.udelay = i2c_udelay; |
357 | btv->i2c_algo.data = btv; |
358 | btv->c.i2c_adap.algo_data = &btv->i2c_algo; |
359 | } |
360 | btv->c.i2c_adap.owner = THIS_MODULE; |
361 | |
362 | btv->c.i2c_adap.dev.parent = &btv->c.pci->dev; |
363 | snprintf(buf: btv->c.i2c_adap.name, size: sizeof(btv->c.i2c_adap.name), |
364 | fmt: "bt%d #%d [%s]" , btv->id, btv->c.nr, |
365 | btv->use_i2c_hw ? "hw" : "sw" ); |
366 | |
367 | i2c_set_adapdata(adap: &btv->c.i2c_adap, data: &btv->c.v4l2_dev); |
368 | btv->i2c_client.adapter = &btv->c.i2c_adap; |
369 | |
370 | |
371 | if (btv->use_i2c_hw) { |
372 | btv->i2c_rc = i2c_add_adapter(adap: &btv->c.i2c_adap); |
373 | } else { |
374 | bttv_bit_setscl(data: btv,state: 1); |
375 | bttv_bit_setsda(data: btv,state: 1); |
376 | btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap); |
377 | } |
378 | if (0 == btv->i2c_rc && i2c_scan) |
379 | do_i2c_scan(name: btv->c.v4l2_dev.name, c: &btv->i2c_client); |
380 | |
381 | return btv->i2c_rc; |
382 | } |
383 | |
384 | int fini_bttv_i2c(struct bttv *btv) |
385 | { |
386 | if (btv->i2c_rc == 0) |
387 | i2c_del_adapter(adap: &btv->c.i2c_adap); |
388 | |
389 | return 0; |
390 | } |
391 | |