sound/i2c/i2c.c

25 static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus,
34 static int snd_i2c_bus_free(struct snd_i2c_bus *bus)
39 	if (snd_BUG_ON(!bus))
41 	while (!list_empty(&bus->devices)) {
42 		device = snd_i2c_device(bus->devices.next);
45 	if (bus->master)
46 		list_del(&bus->buses);
48 		while (!list_empty(&bus->buses)) {
49 			slave = snd_i2c_slave_bus(bus->buses.next);
50 			snd_device_free(bus->card, slave);
53 	if (bus->private_free)
54 		bus->private_free(bus);
55 	kfree(bus);
61 	struct snd_i2c_bus *bus = device->device_data;
62 	return snd_i2c_bus_free(bus);
68 	struct snd_i2c_bus *bus;
75 	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
76 	if (bus == NULL)
78 	mutex_init(&bus->lock_mutex);
79 	INIT_LIST_HEAD(&bus->devices);
80 	INIT_LIST_HEAD(&bus->buses);
81 	bus->card = card;
82 	bus->ops = &snd_i2c_bit_ops;
84 		list_add_tail(&bus->buses, &master->buses);
85 		bus->master = master;
87 	strscpy(bus->name, name, sizeof(bus->name));
88 	err = snd_device_new(card, SNDRV_DEV_BUS, bus, &ops);
90 		snd_i2c_bus_free(bus);
93 	*ri2c = bus;
99 int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name,
105 	if (snd_BUG_ON(!bus))
112 	list_add_tail(&device->list, &bus->devices);
113 	device->bus = bus;
122 	if (device->bus)
134 	return device->bus->ops->sendbytes(device, bytes, count);
141 	return device->bus->ops->readbytes(device, bytes, count);
146 int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr)
148 	return bus->ops->probeaddr(bus, addr);
157 static inline void snd_i2c_bit_hw_start(struct snd_i2c_bus *bus)
159 	if (bus->hw_ops.bit->start)
160 		bus->hw_ops.bit->start(bus);
163 static inline void snd_i2c_bit_hw_stop(struct snd_i2c_bus *bus)
165 	if (bus->hw_ops.bit->stop)
166 		bus->hw_ops.bit->stop(bus);
169 static void snd_i2c_bit_direction(struct snd_i2c_bus *bus, int clock, int data)
171 	if (bus->hw_ops.bit->direction)
172 		bus->hw_ops.bit->direction(bus, clock, data);
175 static void snd_i2c_bit_set(struct snd_i2c_bus *bus, int clock, int data)
177 	bus->hw_ops.bit->setlines(bus, clock, data);
181 static int snd_i2c_bit_clock(struct snd_i2c_bus *bus)
183 	if (bus->hw_ops.bit->getclock)
184 		return bus->hw_ops.bit->getclock(bus);
189 static int snd_i2c_bit_data(struct snd_i2c_bus *bus, int ack)
191 	return bus->hw_ops.bit->getdata(bus, ack);
194 static void snd_i2c_bit_start(struct snd_i2c_bus *bus)
196 	snd_i2c_bit_hw_start(bus);
197 	snd_i2c_bit_direction(bus, 1, 1);	/* SCL - wr, SDA - wr */
198 	snd_i2c_bit_set(bus, 1, 1);
199 	snd_i2c_bit_set(bus, 1, 0);
200 	snd_i2c_bit_set(bus, 0, 0);
203 static void snd_i2c_bit_stop(struct snd_i2c_bus *bus)
205 	snd_i2c_bit_set(bus, 0, 0);
206 	snd_i2c_bit_set(bus, 1, 0);
207 	snd_i2c_bit_set(bus, 1, 1);
208 	snd_i2c_bit_hw_stop(bus);
211 static void snd_i2c_bit_send(struct snd_i2c_bus *bus, int data)
213 	snd_i2c_bit_set(bus, 0, data);
214 	snd_i2c_bit_set(bus, 1, data);
215 	snd_i2c_bit_set(bus, 0, data);
218 static int snd_i2c_bit_ack(struct snd_i2c_bus *bus)
222 	snd_i2c_bit_set(bus, 0, 1);
223 	snd_i2c_bit_set(bus, 1, 1);
224 	snd_i2c_bit_direction(bus, 1, 0);	/* SCL - wr, SDA - rd */
225 	ack = snd_i2c_bit_data(bus, 1);
226 	snd_i2c_bit_direction(bus, 1, 1);	/* SCL - wr, SDA - wr */
227 	snd_i2c_bit_set(bus, 0, 1);
231 static int snd_i2c_bit_sendbyte(struct snd_i2c_bus *bus, unsigned char data)
236 		snd_i2c_bit_send(bus, !!(data & (1 << i)));
237 	err = snd_i2c_bit_ack(bus);
243 static int snd_i2c_bit_readbyte(struct snd_i2c_bus *bus, int last)
248 	snd_i2c_bit_set(bus, 0, 1);
249 	snd_i2c_bit_direction(bus, 1, 0);	/* SCL - wr, SDA - rd */
251 		snd_i2c_bit_set(bus, 1, 1);
252 		if (snd_i2c_bit_data(bus, 0))
254 		snd_i2c_bit_set(bus, 0, 1);
256 	snd_i2c_bit_direction(bus, 1, 1);	/* SCL - wr, SDA - wr */
257 	snd_i2c_bit_send(bus, !!last);
264 	struct snd_i2c_bus *bus = device->bus;
269 	snd_i2c_bit_start(bus);
270 	err = snd_i2c_bit_sendbyte(bus, device->addr << 1);
272 		snd_i2c_bit_hw_stop(bus);
276 		err = snd_i2c_bit_sendbyte(bus, *bytes++);
278 			snd_i2c_bit_hw_stop(bus);
283 	snd_i2c_bit_stop(bus);
290 	struct snd_i2c_bus *bus = device->bus;
295 	snd_i2c_bit_start(bus);
296 	err = snd_i2c_bit_sendbyte(bus, (device->addr << 1) | 1);
298 		snd_i2c_bit_hw_stop(bus);
302 		err = snd_i2c_bit_readbyte(bus, count == 0);
304 			snd_i2c_bit_hw_stop(bus);
310 	snd_i2c_bit_stop(bus);
314 static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, unsigned short addr)
322 	snd_i2c_bit_start(bus);
323 	err = snd_i2c_bit_sendbyte(bus, addr << 1);
324 	snd_i2c_bit_stop(bus);