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 LT |
51 | |
52 | snd_assert(bus != NULL, return -EINVAL); | |
53 | while (!list_empty(&bus->devices)) { | |
54 | device = snd_i2c_device(bus->devices.next); | |
55 | snd_i2c_device_free(device); | |
56 | } | |
57 | if (bus->master) | |
58 | list_del(&bus->buses); | |
59 | else { | |
60 | while (!list_empty(&bus->buses)) { | |
61 | slave = snd_i2c_slave_bus(bus->buses.next); | |
62 | snd_device_free(bus->card, slave); | |
63 | } | |
64 | } | |
65 | if (bus->private_free) | |
66 | bus->private_free(bus); | |
67 | kfree(bus); | |
68 | return 0; | |
69 | } | |
70 | ||
97f02e05 | 71 | static int snd_i2c_bus_dev_free(struct snd_device *device) |
1da177e4 | 72 | { |
97f02e05 | 73 | struct snd_i2c_bus *bus = device->device_data; |
1da177e4 LT |
74 | return snd_i2c_bus_free(bus); |
75 | } | |
76 | ||
97f02e05 TI |
77 | int snd_i2c_bus_create(struct snd_card *card, const char *name, |
78 | struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c) | |
1da177e4 | 79 | { |
97f02e05 | 80 | struct snd_i2c_bus *bus; |
1da177e4 | 81 | int err; |
97f02e05 | 82 | static struct snd_device_ops ops = { |
1da177e4 LT |
83 | .dev_free = snd_i2c_bus_dev_free, |
84 | }; | |
85 | ||
86 | *ri2c = NULL; | |
561b220a | 87 | bus = kzalloc(sizeof(*bus), GFP_KERNEL); |
1da177e4 LT |
88 | if (bus == NULL) |
89 | return -ENOMEM; | |
ef9f0a42 | 90 | mutex_init(&bus->lock_mutex); |
1da177e4 LT |
91 | INIT_LIST_HEAD(&bus->devices); |
92 | INIT_LIST_HEAD(&bus->buses); | |
93 | bus->card = card; | |
94 | bus->ops = &snd_i2c_bit_ops; | |
95 | if (master) { | |
96 | list_add_tail(&bus->buses, &master->buses); | |
97 | bus->master = master; | |
98 | } | |
99 | strlcpy(bus->name, name, sizeof(bus->name)); | |
100 | if ((err = snd_device_new(card, SNDRV_DEV_BUS, bus, &ops)) < 0) { | |
101 | snd_i2c_bus_free(bus); | |
102 | return err; | |
103 | } | |
104 | *ri2c = bus; | |
105 | return 0; | |
106 | } | |
107 | ||
57c65c11 TI |
108 | EXPORT_SYMBOL(snd_i2c_bus_create); |
109 | ||
97f02e05 TI |
110 | int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name, |
111 | unsigned char addr, struct snd_i2c_device **rdevice) | |
1da177e4 | 112 | { |
97f02e05 | 113 | struct snd_i2c_device *device; |
1da177e4 LT |
114 | |
115 | *rdevice = NULL; | |
116 | snd_assert(bus != NULL, return -EINVAL); | |
561b220a | 117 | device = kzalloc(sizeof(*device), GFP_KERNEL); |
1da177e4 LT |
118 | if (device == NULL) |
119 | return -ENOMEM; | |
120 | device->addr = addr; | |
121 | strlcpy(device->name, name, sizeof(device->name)); | |
122 | list_add_tail(&device->list, &bus->devices); | |
123 | device->bus = bus; | |
124 | *rdevice = device; | |
125 | return 0; | |
126 | } | |
127 | ||
57c65c11 TI |
128 | EXPORT_SYMBOL(snd_i2c_device_create); |
129 | ||
97f02e05 | 130 | int snd_i2c_device_free(struct snd_i2c_device *device) |
1da177e4 LT |
131 | { |
132 | if (device->bus) | |
133 | list_del(&device->list); | |
134 | if (device->private_free) | |
135 | device->private_free(device); | |
136 | kfree(device); | |
137 | return 0; | |
138 | } | |
139 | ||
57c65c11 TI |
140 | EXPORT_SYMBOL(snd_i2c_device_free); |
141 | ||
97f02e05 | 142 | int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count) |
1da177e4 LT |
143 | { |
144 | return device->bus->ops->sendbytes(device, bytes, count); | |
145 | } | |
146 | ||
57c65c11 | 147 | EXPORT_SYMBOL(snd_i2c_sendbytes); |
1da177e4 | 148 | |
97f02e05 | 149 | int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count) |
1da177e4 LT |
150 | { |
151 | return device->bus->ops->readbytes(device, bytes, count); | |
152 | } | |
153 | ||
57c65c11 TI |
154 | EXPORT_SYMBOL(snd_i2c_readbytes); |
155 | ||
97f02e05 | 156 | int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr) |
1da177e4 LT |
157 | { |
158 | return bus->ops->probeaddr(bus, addr); | |
159 | } | |
160 | ||
57c65c11 TI |
161 | EXPORT_SYMBOL(snd_i2c_probeaddr); |
162 | ||
1da177e4 LT |
163 | /* |
164 | * bit-operations | |
165 | */ | |
166 | ||
97f02e05 | 167 | static inline void snd_i2c_bit_hw_start(struct snd_i2c_bus *bus) |
1da177e4 LT |
168 | { |
169 | if (bus->hw_ops.bit->start) | |
170 | bus->hw_ops.bit->start(bus); | |
171 | } | |
172 | ||
97f02e05 | 173 | static inline void snd_i2c_bit_hw_stop(struct snd_i2c_bus *bus) |
1da177e4 LT |
174 | { |
175 | if (bus->hw_ops.bit->stop) | |
176 | bus->hw_ops.bit->stop(bus); | |
177 | } | |
178 | ||
97f02e05 | 179 | static void snd_i2c_bit_direction(struct snd_i2c_bus *bus, int clock, int data) |
1da177e4 LT |
180 | { |
181 | if (bus->hw_ops.bit->direction) | |
182 | bus->hw_ops.bit->direction(bus, clock, data); | |
183 | } | |
184 | ||
97f02e05 | 185 | static void snd_i2c_bit_set(struct snd_i2c_bus *bus, int clock, int data) |
1da177e4 LT |
186 | { |
187 | bus->hw_ops.bit->setlines(bus, clock, data); | |
188 | } | |
189 | ||
190 | #if 0 | |
97f02e05 | 191 | static int snd_i2c_bit_clock(struct snd_i2c_bus *bus) |
1da177e4 LT |
192 | { |
193 | if (bus->hw_ops.bit->getclock) | |
194 | return bus->hw_ops.bit->getclock(bus); | |
195 | return -ENXIO; | |
196 | } | |
197 | #endif | |
198 | ||
97f02e05 | 199 | static int snd_i2c_bit_data(struct snd_i2c_bus *bus, int ack) |
1da177e4 LT |
200 | { |
201 | return bus->hw_ops.bit->getdata(bus, ack); | |
202 | } | |
203 | ||
97f02e05 | 204 | static void snd_i2c_bit_start(struct snd_i2c_bus *bus) |
1da177e4 LT |
205 | { |
206 | snd_i2c_bit_hw_start(bus); | |
207 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
208 | snd_i2c_bit_set(bus, 1, 1); | |
209 | snd_i2c_bit_set(bus, 1, 0); | |
210 | snd_i2c_bit_set(bus, 0, 0); | |
211 | } | |
212 | ||
97f02e05 | 213 | static void snd_i2c_bit_stop(struct snd_i2c_bus *bus) |
1da177e4 LT |
214 | { |
215 | snd_i2c_bit_set(bus, 0, 0); | |
216 | snd_i2c_bit_set(bus, 1, 0); | |
217 | snd_i2c_bit_set(bus, 1, 1); | |
218 | snd_i2c_bit_hw_stop(bus); | |
219 | } | |
220 | ||
97f02e05 | 221 | static void snd_i2c_bit_send(struct snd_i2c_bus *bus, int data) |
1da177e4 LT |
222 | { |
223 | snd_i2c_bit_set(bus, 0, data); | |
224 | snd_i2c_bit_set(bus, 1, data); | |
225 | snd_i2c_bit_set(bus, 0, data); | |
226 | } | |
227 | ||
97f02e05 | 228 | static int snd_i2c_bit_ack(struct snd_i2c_bus *bus) |
1da177e4 LT |
229 | { |
230 | int ack; | |
231 | ||
232 | snd_i2c_bit_set(bus, 0, 1); | |
233 | snd_i2c_bit_set(bus, 1, 1); | |
234 | snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */ | |
235 | ack = snd_i2c_bit_data(bus, 1); | |
236 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
237 | snd_i2c_bit_set(bus, 0, 1); | |
238 | return ack ? -EIO : 0; | |
239 | } | |
240 | ||
97f02e05 | 241 | static int snd_i2c_bit_sendbyte(struct snd_i2c_bus *bus, unsigned char data) |
1da177e4 LT |
242 | { |
243 | int i, err; | |
244 | ||
245 | for (i = 7; i >= 0; i--) | |
246 | snd_i2c_bit_send(bus, !!(data & (1 << i))); | |
247 | if ((err = snd_i2c_bit_ack(bus)) < 0) | |
248 | return err; | |
249 | return 0; | |
250 | } | |
251 | ||
97f02e05 | 252 | static int snd_i2c_bit_readbyte(struct snd_i2c_bus *bus, int last) |
1da177e4 LT |
253 | { |
254 | int i; | |
255 | unsigned char data = 0; | |
256 | ||
257 | snd_i2c_bit_set(bus, 0, 1); | |
258 | snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */ | |
259 | for (i = 7; i >= 0; i--) { | |
260 | snd_i2c_bit_set(bus, 1, 1); | |
261 | if (snd_i2c_bit_data(bus, 0)) | |
262 | data |= (1 << i); | |
263 | snd_i2c_bit_set(bus, 0, 1); | |
264 | } | |
265 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
266 | snd_i2c_bit_send(bus, !!last); | |
267 | return data; | |
268 | } | |
269 | ||
97f02e05 TI |
270 | static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device, |
271 | unsigned char *bytes, int count) | |
1da177e4 | 272 | { |
97f02e05 | 273 | struct snd_i2c_bus *bus = device->bus; |
1da177e4 LT |
274 | int err, res = 0; |
275 | ||
276 | if (device->flags & SND_I2C_DEVICE_ADDRTEN) | |
277 | return -EIO; /* not yet implemented */ | |
278 | snd_i2c_bit_start(bus); | |
279 | if ((err = snd_i2c_bit_sendbyte(bus, device->addr << 1)) < 0) { | |
280 | snd_i2c_bit_hw_stop(bus); | |
281 | return err; | |
282 | } | |
283 | while (count-- > 0) { | |
284 | if ((err = snd_i2c_bit_sendbyte(bus, *bytes++)) < 0) { | |
285 | snd_i2c_bit_hw_stop(bus); | |
286 | return err; | |
287 | } | |
288 | res++; | |
289 | } | |
290 | snd_i2c_bit_stop(bus); | |
291 | return res; | |
292 | } | |
293 | ||
97f02e05 TI |
294 | static int snd_i2c_bit_readbytes(struct snd_i2c_device *device, |
295 | unsigned char *bytes, int count) | |
1da177e4 | 296 | { |
97f02e05 | 297 | struct snd_i2c_bus *bus = device->bus; |
1da177e4 LT |
298 | int err, res = 0; |
299 | ||
300 | if (device->flags & SND_I2C_DEVICE_ADDRTEN) | |
301 | return -EIO; /* not yet implemented */ | |
302 | snd_i2c_bit_start(bus); | |
303 | if ((err = snd_i2c_bit_sendbyte(bus, (device->addr << 1) | 1)) < 0) { | |
304 | snd_i2c_bit_hw_stop(bus); | |
305 | return err; | |
306 | } | |
307 | while (count-- > 0) { | |
308 | if ((err = snd_i2c_bit_readbyte(bus, count == 0)) < 0) { | |
309 | snd_i2c_bit_hw_stop(bus); | |
310 | return err; | |
311 | } | |
312 | *bytes++ = (unsigned char)err; | |
313 | res++; | |
314 | } | |
315 | snd_i2c_bit_stop(bus); | |
316 | return res; | |
317 | } | |
318 | ||
97f02e05 | 319 | static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, unsigned short addr) |
1da177e4 LT |
320 | { |
321 | int err; | |
322 | ||
323 | if (addr & 0x8000) /* 10-bit address */ | |
324 | return -EIO; /* not yet implemented */ | |
325 | if (addr & 0x7f80) /* invalid address */ | |
326 | return -EINVAL; | |
327 | snd_i2c_bit_start(bus); | |
328 | err = snd_i2c_bit_sendbyte(bus, addr << 1); | |
329 | snd_i2c_bit_stop(bus); | |
330 | return err; | |
331 | } | |
332 | ||
1da177e4 LT |
333 | |
334 | static int __init alsa_i2c_init(void) | |
335 | { | |
336 | return 0; | |
337 | } | |
338 | ||
339 | static void __exit alsa_i2c_exit(void) | |
340 | { | |
341 | } | |
342 | ||
343 | module_init(alsa_i2c_init) | |
344 | module_exit(alsa_i2c_exit) |