]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Generic i2c interface for ALSA | |
3 | * | |
4 | * (c) 1998 Gerd Knorr <kraxel@cs.tu-berlin.de> | |
c1017a4c | 5 | * Modified for the ALSA driver by Jaroslav Kysela <perex@perex.cz> |
1da177e4 LT |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
20 | * | |
21 | */ | |
22 | ||
1da177e4 LT |
23 | #include <linux/init.h> |
24 | #include <linux/slab.h> | |
25 | #include <linux/string.h> | |
26 | #include <linux/errno.h> | |
27 | #include <sound/core.h> | |
28 | #include <sound/i2c.h> | |
29 | ||
c1017a4c | 30 | MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>"); |
1da177e4 LT |
31 | MODULE_DESCRIPTION("Generic i2c interface for ALSA"); |
32 | MODULE_LICENSE("GPL"); | |
33 | ||
97f02e05 TI |
34 | static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device, |
35 | unsigned char *bytes, int count); | |
36 | static int snd_i2c_bit_readbytes(struct snd_i2c_device *device, | |
37 | unsigned char *bytes, int count); | |
38 | static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, | |
39 | unsigned short addr); | |
40 | ||
41 | static struct snd_i2c_ops snd_i2c_bit_ops = { | |
1da177e4 LT |
42 | .sendbytes = snd_i2c_bit_sendbytes, |
43 | .readbytes = snd_i2c_bit_readbytes, | |
44 | .probeaddr = snd_i2c_bit_probeaddr, | |
45 | }; | |
46 | ||
97f02e05 | 47 | static int snd_i2c_bus_free(struct snd_i2c_bus *bus) |
1da177e4 | 48 | { |
97f02e05 TI |
49 | struct snd_i2c_bus *slave; |
50 | struct snd_i2c_device *device; | |
1da177e4 | 51 | |
5e246b85 TI |
52 | if (snd_BUG_ON(!bus)) |
53 | return -EINVAL; | |
1da177e4 LT |
54 | while (!list_empty(&bus->devices)) { |
55 | device = snd_i2c_device(bus->devices.next); | |
56 | snd_i2c_device_free(device); | |
57 | } | |
58 | if (bus->master) | |
59 | list_del(&bus->buses); | |
60 | else { | |
61 | while (!list_empty(&bus->buses)) { | |
62 | slave = snd_i2c_slave_bus(bus->buses.next); | |
63 | snd_device_free(bus->card, slave); | |
64 | } | |
65 | } | |
66 | if (bus->private_free) | |
67 | bus->private_free(bus); | |
68 | kfree(bus); | |
69 | return 0; | |
70 | } | |
71 | ||
97f02e05 | 72 | static int snd_i2c_bus_dev_free(struct snd_device *device) |
1da177e4 | 73 | { |
97f02e05 | 74 | struct snd_i2c_bus *bus = device->device_data; |
1da177e4 LT |
75 | return snd_i2c_bus_free(bus); |
76 | } | |
77 | ||
97f02e05 TI |
78 | int snd_i2c_bus_create(struct snd_card *card, const char *name, |
79 | struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c) | |
1da177e4 | 80 | { |
97f02e05 | 81 | struct snd_i2c_bus *bus; |
1da177e4 | 82 | int err; |
97f02e05 | 83 | static struct snd_device_ops ops = { |
1da177e4 LT |
84 | .dev_free = snd_i2c_bus_dev_free, |
85 | }; | |
86 | ||
87 | *ri2c = NULL; | |
561b220a | 88 | bus = kzalloc(sizeof(*bus), GFP_KERNEL); |
1da177e4 LT |
89 | if (bus == NULL) |
90 | return -ENOMEM; | |
ef9f0a42 | 91 | mutex_init(&bus->lock_mutex); |
1da177e4 LT |
92 | INIT_LIST_HEAD(&bus->devices); |
93 | INIT_LIST_HEAD(&bus->buses); | |
94 | bus->card = card; | |
95 | bus->ops = &snd_i2c_bit_ops; | |
96 | if (master) { | |
97 | list_add_tail(&bus->buses, &master->buses); | |
98 | bus->master = master; | |
99 | } | |
100 | strlcpy(bus->name, name, sizeof(bus->name)); | |
1cff399e BW |
101 | err = snd_device_new(card, SNDRV_DEV_BUS, bus, &ops); |
102 | if (err < 0) { | |
1da177e4 LT |
103 | snd_i2c_bus_free(bus); |
104 | return err; | |
105 | } | |
106 | *ri2c = bus; | |
107 | return 0; | |
108 | } | |
109 | ||
57c65c11 TI |
110 | EXPORT_SYMBOL(snd_i2c_bus_create); |
111 | ||
97f02e05 TI |
112 | int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name, |
113 | unsigned char addr, struct snd_i2c_device **rdevice) | |
1da177e4 | 114 | { |
97f02e05 | 115 | struct snd_i2c_device *device; |
1da177e4 LT |
116 | |
117 | *rdevice = NULL; | |
5e246b85 TI |
118 | if (snd_BUG_ON(!bus)) |
119 | return -EINVAL; | |
561b220a | 120 | device = kzalloc(sizeof(*device), GFP_KERNEL); |
1da177e4 LT |
121 | if (device == NULL) |
122 | return -ENOMEM; | |
123 | device->addr = addr; | |
124 | strlcpy(device->name, name, sizeof(device->name)); | |
125 | list_add_tail(&device->list, &bus->devices); | |
126 | device->bus = bus; | |
127 | *rdevice = device; | |
128 | return 0; | |
129 | } | |
130 | ||
57c65c11 TI |
131 | EXPORT_SYMBOL(snd_i2c_device_create); |
132 | ||
97f02e05 | 133 | int snd_i2c_device_free(struct snd_i2c_device *device) |
1da177e4 LT |
134 | { |
135 | if (device->bus) | |
136 | list_del(&device->list); | |
137 | if (device->private_free) | |
138 | device->private_free(device); | |
139 | kfree(device); | |
140 | return 0; | |
141 | } | |
142 | ||
57c65c11 TI |
143 | EXPORT_SYMBOL(snd_i2c_device_free); |
144 | ||
97f02e05 | 145 | int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count) |
1da177e4 LT |
146 | { |
147 | return device->bus->ops->sendbytes(device, bytes, count); | |
148 | } | |
149 | ||
57c65c11 | 150 | EXPORT_SYMBOL(snd_i2c_sendbytes); |
1da177e4 | 151 | |
97f02e05 | 152 | int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count) |
1da177e4 LT |
153 | { |
154 | return device->bus->ops->readbytes(device, bytes, count); | |
155 | } | |
156 | ||
57c65c11 TI |
157 | EXPORT_SYMBOL(snd_i2c_readbytes); |
158 | ||
97f02e05 | 159 | int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr) |
1da177e4 LT |
160 | { |
161 | return bus->ops->probeaddr(bus, addr); | |
162 | } | |
163 | ||
57c65c11 TI |
164 | EXPORT_SYMBOL(snd_i2c_probeaddr); |
165 | ||
1da177e4 LT |
166 | /* |
167 | * bit-operations | |
168 | */ | |
169 | ||
97f02e05 | 170 | static inline void snd_i2c_bit_hw_start(struct snd_i2c_bus *bus) |
1da177e4 LT |
171 | { |
172 | if (bus->hw_ops.bit->start) | |
173 | bus->hw_ops.bit->start(bus); | |
174 | } | |
175 | ||
97f02e05 | 176 | static inline void snd_i2c_bit_hw_stop(struct snd_i2c_bus *bus) |
1da177e4 LT |
177 | { |
178 | if (bus->hw_ops.bit->stop) | |
179 | bus->hw_ops.bit->stop(bus); | |
180 | } | |
181 | ||
97f02e05 | 182 | static void snd_i2c_bit_direction(struct snd_i2c_bus *bus, int clock, int data) |
1da177e4 LT |
183 | { |
184 | if (bus->hw_ops.bit->direction) | |
185 | bus->hw_ops.bit->direction(bus, clock, data); | |
186 | } | |
187 | ||
97f02e05 | 188 | static void snd_i2c_bit_set(struct snd_i2c_bus *bus, int clock, int data) |
1da177e4 LT |
189 | { |
190 | bus->hw_ops.bit->setlines(bus, clock, data); | |
191 | } | |
192 | ||
193 | #if 0 | |
97f02e05 | 194 | static int snd_i2c_bit_clock(struct snd_i2c_bus *bus) |
1da177e4 LT |
195 | { |
196 | if (bus->hw_ops.bit->getclock) | |
197 | return bus->hw_ops.bit->getclock(bus); | |
198 | return -ENXIO; | |
199 | } | |
200 | #endif | |
201 | ||
97f02e05 | 202 | static int snd_i2c_bit_data(struct snd_i2c_bus *bus, int ack) |
1da177e4 LT |
203 | { |
204 | return bus->hw_ops.bit->getdata(bus, ack); | |
205 | } | |
206 | ||
97f02e05 | 207 | static void snd_i2c_bit_start(struct snd_i2c_bus *bus) |
1da177e4 LT |
208 | { |
209 | snd_i2c_bit_hw_start(bus); | |
210 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
211 | snd_i2c_bit_set(bus, 1, 1); | |
212 | snd_i2c_bit_set(bus, 1, 0); | |
213 | snd_i2c_bit_set(bus, 0, 0); | |
214 | } | |
215 | ||
97f02e05 | 216 | static void snd_i2c_bit_stop(struct snd_i2c_bus *bus) |
1da177e4 LT |
217 | { |
218 | snd_i2c_bit_set(bus, 0, 0); | |
219 | snd_i2c_bit_set(bus, 1, 0); | |
220 | snd_i2c_bit_set(bus, 1, 1); | |
221 | snd_i2c_bit_hw_stop(bus); | |
222 | } | |
223 | ||
97f02e05 | 224 | static void snd_i2c_bit_send(struct snd_i2c_bus *bus, int data) |
1da177e4 LT |
225 | { |
226 | snd_i2c_bit_set(bus, 0, data); | |
227 | snd_i2c_bit_set(bus, 1, data); | |
228 | snd_i2c_bit_set(bus, 0, data); | |
229 | } | |
230 | ||
97f02e05 | 231 | static int snd_i2c_bit_ack(struct snd_i2c_bus *bus) |
1da177e4 LT |
232 | { |
233 | int ack; | |
234 | ||
235 | snd_i2c_bit_set(bus, 0, 1); | |
236 | snd_i2c_bit_set(bus, 1, 1); | |
237 | snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */ | |
238 | ack = snd_i2c_bit_data(bus, 1); | |
239 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
240 | snd_i2c_bit_set(bus, 0, 1); | |
241 | return ack ? -EIO : 0; | |
242 | } | |
243 | ||
97f02e05 | 244 | static int snd_i2c_bit_sendbyte(struct snd_i2c_bus *bus, unsigned char data) |
1da177e4 LT |
245 | { |
246 | int i, err; | |
247 | ||
248 | for (i = 7; i >= 0; i--) | |
249 | snd_i2c_bit_send(bus, !!(data & (1 << i))); | |
1cff399e BW |
250 | err = snd_i2c_bit_ack(bus); |
251 | if (err < 0) | |
1da177e4 LT |
252 | return err; |
253 | return 0; | |
254 | } | |
255 | ||
97f02e05 | 256 | static int snd_i2c_bit_readbyte(struct snd_i2c_bus *bus, int last) |
1da177e4 LT |
257 | { |
258 | int i; | |
259 | unsigned char data = 0; | |
260 | ||
261 | snd_i2c_bit_set(bus, 0, 1); | |
262 | snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */ | |
263 | for (i = 7; i >= 0; i--) { | |
264 | snd_i2c_bit_set(bus, 1, 1); | |
265 | if (snd_i2c_bit_data(bus, 0)) | |
266 | data |= (1 << i); | |
267 | snd_i2c_bit_set(bus, 0, 1); | |
268 | } | |
269 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
270 | snd_i2c_bit_send(bus, !!last); | |
271 | return data; | |
272 | } | |
273 | ||
97f02e05 TI |
274 | static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device, |
275 | unsigned char *bytes, int count) | |
1da177e4 | 276 | { |
97f02e05 | 277 | struct snd_i2c_bus *bus = device->bus; |
1da177e4 LT |
278 | int err, res = 0; |
279 | ||
280 | if (device->flags & SND_I2C_DEVICE_ADDRTEN) | |
281 | return -EIO; /* not yet implemented */ | |
282 | snd_i2c_bit_start(bus); | |
1cff399e BW |
283 | err = snd_i2c_bit_sendbyte(bus, device->addr << 1); |
284 | if (err < 0) { | |
1da177e4 LT |
285 | snd_i2c_bit_hw_stop(bus); |
286 | return err; | |
287 | } | |
288 | while (count-- > 0) { | |
1cff399e BW |
289 | err = snd_i2c_bit_sendbyte(bus, *bytes++); |
290 | if (err < 0) { | |
1da177e4 LT |
291 | snd_i2c_bit_hw_stop(bus); |
292 | return err; | |
293 | } | |
294 | res++; | |
295 | } | |
296 | snd_i2c_bit_stop(bus); | |
297 | return res; | |
298 | } | |
299 | ||
97f02e05 TI |
300 | static int snd_i2c_bit_readbytes(struct snd_i2c_device *device, |
301 | unsigned char *bytes, int count) | |
1da177e4 | 302 | { |
97f02e05 | 303 | struct snd_i2c_bus *bus = device->bus; |
1da177e4 LT |
304 | int err, res = 0; |
305 | ||
306 | if (device->flags & SND_I2C_DEVICE_ADDRTEN) | |
307 | return -EIO; /* not yet implemented */ | |
308 | snd_i2c_bit_start(bus); | |
1cff399e BW |
309 | err = snd_i2c_bit_sendbyte(bus, (device->addr << 1) | 1); |
310 | if (err < 0) { | |
1da177e4 LT |
311 | snd_i2c_bit_hw_stop(bus); |
312 | return err; | |
313 | } | |
314 | while (count-- > 0) { | |
1cff399e BW |
315 | err = snd_i2c_bit_readbyte(bus, count == 0); |
316 | if (err < 0) { | |
1da177e4 LT |
317 | snd_i2c_bit_hw_stop(bus); |
318 | return err; | |
319 | } | |
320 | *bytes++ = (unsigned char)err; | |
321 | res++; | |
322 | } | |
323 | snd_i2c_bit_stop(bus); | |
324 | return res; | |
325 | } | |
326 | ||
97f02e05 | 327 | static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, unsigned short addr) |
1da177e4 LT |
328 | { |
329 | int err; | |
330 | ||
331 | if (addr & 0x8000) /* 10-bit address */ | |
332 | return -EIO; /* not yet implemented */ | |
333 | if (addr & 0x7f80) /* invalid address */ | |
334 | return -EINVAL; | |
335 | snd_i2c_bit_start(bus); | |
336 | err = snd_i2c_bit_sendbyte(bus, addr << 1); | |
337 | snd_i2c_bit_stop(bus); | |
338 | return err; | |
339 | } | |
340 | ||
1da177e4 LT |
341 | |
342 | static int __init alsa_i2c_init(void) | |
343 | { | |
344 | return 0; | |
345 | } | |
346 | ||
347 | static void __exit alsa_i2c_exit(void) | |
348 | { | |
349 | } | |
350 | ||
351 | module_init(alsa_i2c_init) | |
352 | module_exit(alsa_i2c_exit) |