Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Generic i2c interface for ALSA | |
3 | * | |
4 | * (c) 1998 Gerd Knorr <kraxel@cs.tu-berlin.de> | |
5 | * Modified for the ALSA driver by Jaroslav Kysela <perex@suse.cz> | |
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 | ||
23 | #include <sound/driver.h> | |
24 | #include <linux/init.h> | |
25 | #include <linux/slab.h> | |
26 | #include <linux/string.h> | |
27 | #include <linux/errno.h> | |
28 | #include <sound/core.h> | |
29 | #include <sound/i2c.h> | |
30 | ||
31 | MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>"); | |
32 | MODULE_DESCRIPTION("Generic i2c interface for ALSA"); | |
33 | MODULE_LICENSE("GPL"); | |
34 | ||
97f02e05 TI |
35 | static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device, |
36 | unsigned char *bytes, int count); | |
37 | static int snd_i2c_bit_readbytes(struct snd_i2c_device *device, | |
38 | unsigned char *bytes, int count); | |
39 | static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, | |
40 | unsigned short addr); | |
41 | ||
42 | static struct snd_i2c_ops snd_i2c_bit_ops = { | |
1da177e4 LT |
43 | .sendbytes = snd_i2c_bit_sendbytes, |
44 | .readbytes = snd_i2c_bit_readbytes, | |
45 | .probeaddr = snd_i2c_bit_probeaddr, | |
46 | }; | |
47 | ||
97f02e05 | 48 | static int snd_i2c_bus_free(struct snd_i2c_bus *bus) |
1da177e4 | 49 | { |
97f02e05 TI |
50 | struct snd_i2c_bus *slave; |
51 | struct snd_i2c_device *device; | |
1da177e4 LT |
52 | |
53 | snd_assert(bus != NULL, return -EINVAL); | |
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)); | |
101 | if ((err = snd_device_new(card, SNDRV_DEV_BUS, bus, &ops)) < 0) { | |
102 | snd_i2c_bus_free(bus); | |
103 | return err; | |
104 | } | |
105 | *ri2c = bus; | |
106 | return 0; | |
107 | } | |
108 | ||
57c65c11 TI |
109 | EXPORT_SYMBOL(snd_i2c_bus_create); |
110 | ||
97f02e05 TI |
111 | int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name, |
112 | unsigned char addr, struct snd_i2c_device **rdevice) | |
1da177e4 | 113 | { |
97f02e05 | 114 | struct snd_i2c_device *device; |
1da177e4 LT |
115 | |
116 | *rdevice = NULL; | |
117 | snd_assert(bus != NULL, return -EINVAL); | |
561b220a | 118 | device = kzalloc(sizeof(*device), GFP_KERNEL); |
1da177e4 LT |
119 | if (device == NULL) |
120 | return -ENOMEM; | |
121 | device->addr = addr; | |
122 | strlcpy(device->name, name, sizeof(device->name)); | |
123 | list_add_tail(&device->list, &bus->devices); | |
124 | device->bus = bus; | |
125 | *rdevice = device; | |
126 | return 0; | |
127 | } | |
128 | ||
57c65c11 TI |
129 | EXPORT_SYMBOL(snd_i2c_device_create); |
130 | ||
97f02e05 | 131 | int snd_i2c_device_free(struct snd_i2c_device *device) |
1da177e4 LT |
132 | { |
133 | if (device->bus) | |
134 | list_del(&device->list); | |
135 | if (device->private_free) | |
136 | device->private_free(device); | |
137 | kfree(device); | |
138 | return 0; | |
139 | } | |
140 | ||
57c65c11 TI |
141 | EXPORT_SYMBOL(snd_i2c_device_free); |
142 | ||
97f02e05 | 143 | int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count) |
1da177e4 LT |
144 | { |
145 | return device->bus->ops->sendbytes(device, bytes, count); | |
146 | } | |
147 | ||
57c65c11 | 148 | EXPORT_SYMBOL(snd_i2c_sendbytes); |
1da177e4 | 149 | |
97f02e05 | 150 | int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count) |
1da177e4 LT |
151 | { |
152 | return device->bus->ops->readbytes(device, bytes, count); | |
153 | } | |
154 | ||
57c65c11 TI |
155 | EXPORT_SYMBOL(snd_i2c_readbytes); |
156 | ||
97f02e05 | 157 | int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr) |
1da177e4 LT |
158 | { |
159 | return bus->ops->probeaddr(bus, addr); | |
160 | } | |
161 | ||
57c65c11 TI |
162 | EXPORT_SYMBOL(snd_i2c_probeaddr); |
163 | ||
1da177e4 LT |
164 | /* |
165 | * bit-operations | |
166 | */ | |
167 | ||
97f02e05 | 168 | static inline void snd_i2c_bit_hw_start(struct snd_i2c_bus *bus) |
1da177e4 LT |
169 | { |
170 | if (bus->hw_ops.bit->start) | |
171 | bus->hw_ops.bit->start(bus); | |
172 | } | |
173 | ||
97f02e05 | 174 | static inline void snd_i2c_bit_hw_stop(struct snd_i2c_bus *bus) |
1da177e4 LT |
175 | { |
176 | if (bus->hw_ops.bit->stop) | |
177 | bus->hw_ops.bit->stop(bus); | |
178 | } | |
179 | ||
97f02e05 | 180 | static void snd_i2c_bit_direction(struct snd_i2c_bus *bus, int clock, int data) |
1da177e4 LT |
181 | { |
182 | if (bus->hw_ops.bit->direction) | |
183 | bus->hw_ops.bit->direction(bus, clock, data); | |
184 | } | |
185 | ||
97f02e05 | 186 | static void snd_i2c_bit_set(struct snd_i2c_bus *bus, int clock, int data) |
1da177e4 LT |
187 | { |
188 | bus->hw_ops.bit->setlines(bus, clock, data); | |
189 | } | |
190 | ||
191 | #if 0 | |
97f02e05 | 192 | static int snd_i2c_bit_clock(struct snd_i2c_bus *bus) |
1da177e4 LT |
193 | { |
194 | if (bus->hw_ops.bit->getclock) | |
195 | return bus->hw_ops.bit->getclock(bus); | |
196 | return -ENXIO; | |
197 | } | |
198 | #endif | |
199 | ||
97f02e05 | 200 | static int snd_i2c_bit_data(struct snd_i2c_bus *bus, int ack) |
1da177e4 LT |
201 | { |
202 | return bus->hw_ops.bit->getdata(bus, ack); | |
203 | } | |
204 | ||
97f02e05 | 205 | static void snd_i2c_bit_start(struct snd_i2c_bus *bus) |
1da177e4 LT |
206 | { |
207 | snd_i2c_bit_hw_start(bus); | |
208 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
209 | snd_i2c_bit_set(bus, 1, 1); | |
210 | snd_i2c_bit_set(bus, 1, 0); | |
211 | snd_i2c_bit_set(bus, 0, 0); | |
212 | } | |
213 | ||
97f02e05 | 214 | static void snd_i2c_bit_stop(struct snd_i2c_bus *bus) |
1da177e4 LT |
215 | { |
216 | snd_i2c_bit_set(bus, 0, 0); | |
217 | snd_i2c_bit_set(bus, 1, 0); | |
218 | snd_i2c_bit_set(bus, 1, 1); | |
219 | snd_i2c_bit_hw_stop(bus); | |
220 | } | |
221 | ||
97f02e05 | 222 | static void snd_i2c_bit_send(struct snd_i2c_bus *bus, int data) |
1da177e4 LT |
223 | { |
224 | snd_i2c_bit_set(bus, 0, data); | |
225 | snd_i2c_bit_set(bus, 1, data); | |
226 | snd_i2c_bit_set(bus, 0, data); | |
227 | } | |
228 | ||
97f02e05 | 229 | static int snd_i2c_bit_ack(struct snd_i2c_bus *bus) |
1da177e4 LT |
230 | { |
231 | int ack; | |
232 | ||
233 | snd_i2c_bit_set(bus, 0, 1); | |
234 | snd_i2c_bit_set(bus, 1, 1); | |
235 | snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */ | |
236 | ack = snd_i2c_bit_data(bus, 1); | |
237 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
238 | snd_i2c_bit_set(bus, 0, 1); | |
239 | return ack ? -EIO : 0; | |
240 | } | |
241 | ||
97f02e05 | 242 | static int snd_i2c_bit_sendbyte(struct snd_i2c_bus *bus, unsigned char data) |
1da177e4 LT |
243 | { |
244 | int i, err; | |
245 | ||
246 | for (i = 7; i >= 0; i--) | |
247 | snd_i2c_bit_send(bus, !!(data & (1 << i))); | |
248 | if ((err = snd_i2c_bit_ack(bus)) < 0) | |
249 | return err; | |
250 | return 0; | |
251 | } | |
252 | ||
97f02e05 | 253 | static int snd_i2c_bit_readbyte(struct snd_i2c_bus *bus, int last) |
1da177e4 LT |
254 | { |
255 | int i; | |
256 | unsigned char data = 0; | |
257 | ||
258 | snd_i2c_bit_set(bus, 0, 1); | |
259 | snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */ | |
260 | for (i = 7; i >= 0; i--) { | |
261 | snd_i2c_bit_set(bus, 1, 1); | |
262 | if (snd_i2c_bit_data(bus, 0)) | |
263 | data |= (1 << i); | |
264 | snd_i2c_bit_set(bus, 0, 1); | |
265 | } | |
266 | snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */ | |
267 | snd_i2c_bit_send(bus, !!last); | |
268 | return data; | |
269 | } | |
270 | ||
97f02e05 TI |
271 | static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device, |
272 | unsigned char *bytes, int count) | |
1da177e4 | 273 | { |
97f02e05 | 274 | struct snd_i2c_bus *bus = device->bus; |
1da177e4 LT |
275 | int err, res = 0; |
276 | ||
277 | if (device->flags & SND_I2C_DEVICE_ADDRTEN) | |
278 | return -EIO; /* not yet implemented */ | |
279 | snd_i2c_bit_start(bus); | |
280 | if ((err = snd_i2c_bit_sendbyte(bus, device->addr << 1)) < 0) { | |
281 | snd_i2c_bit_hw_stop(bus); | |
282 | return err; | |
283 | } | |
284 | while (count-- > 0) { | |
285 | if ((err = snd_i2c_bit_sendbyte(bus, *bytes++)) < 0) { | |
286 | snd_i2c_bit_hw_stop(bus); | |
287 | return err; | |
288 | } | |
289 | res++; | |
290 | } | |
291 | snd_i2c_bit_stop(bus); | |
292 | return res; | |
293 | } | |
294 | ||
97f02e05 TI |
295 | static int snd_i2c_bit_readbytes(struct snd_i2c_device *device, |
296 | unsigned char *bytes, int count) | |
1da177e4 | 297 | { |
97f02e05 | 298 | struct snd_i2c_bus *bus = device->bus; |
1da177e4 LT |
299 | int err, res = 0; |
300 | ||
301 | if (device->flags & SND_I2C_DEVICE_ADDRTEN) | |
302 | return -EIO; /* not yet implemented */ | |
303 | snd_i2c_bit_start(bus); | |
304 | if ((err = snd_i2c_bit_sendbyte(bus, (device->addr << 1) | 1)) < 0) { | |
305 | snd_i2c_bit_hw_stop(bus); | |
306 | return err; | |
307 | } | |
308 | while (count-- > 0) { | |
309 | if ((err = snd_i2c_bit_readbyte(bus, count == 0)) < 0) { | |
310 | snd_i2c_bit_hw_stop(bus); | |
311 | return err; | |
312 | } | |
313 | *bytes++ = (unsigned char)err; | |
314 | res++; | |
315 | } | |
316 | snd_i2c_bit_stop(bus); | |
317 | return res; | |
318 | } | |
319 | ||
97f02e05 | 320 | static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, unsigned short addr) |
1da177e4 LT |
321 | { |
322 | int err; | |
323 | ||
324 | if (addr & 0x8000) /* 10-bit address */ | |
325 | return -EIO; /* not yet implemented */ | |
326 | if (addr & 0x7f80) /* invalid address */ | |
327 | return -EINVAL; | |
328 | snd_i2c_bit_start(bus); | |
329 | err = snd_i2c_bit_sendbyte(bus, addr << 1); | |
330 | snd_i2c_bit_stop(bus); | |
331 | return err; | |
332 | } | |
333 | ||
1da177e4 LT |
334 | |
335 | static int __init alsa_i2c_init(void) | |
336 | { | |
337 | return 0; | |
338 | } | |
339 | ||
340 | static void __exit alsa_i2c_exit(void) | |
341 | { | |
342 | } | |
343 | ||
344 | module_init(alsa_i2c_init) | |
345 | module_exit(alsa_i2c_exit) |