2 * Driver for the Auvitek AU0828 USB bridge
4 * Copyright (c) 2008 Steven Toth <stoth@linuxtv.org>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
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., 675 Mass Ave, Cambridge, MA 02139, USA.
22 #include <linux/module.h>
23 #include <linux/moduleparam.h>
24 #include <linux/init.h>
25 #include <linux/delay.h>
30 #include <media/v4l2-common.h>
33 module_param(i2c_scan, int, 0444);
34 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
36 #define I2C_WAIT_DELAY 512
37 #define I2C_WAIT_RETRY 64
39 static inline int i2c_slave_did_write_ack(struct i2c_adapter *i2c_adap)
41 struct au0828_dev *dev = i2c_adap->algo_data;
42 return au0828_read(dev, REG_201) & 0x08 ? 0 : 1;
45 static inline int i2c_slave_did_read_ack(struct i2c_adapter *i2c_adap)
47 struct au0828_dev *dev = i2c_adap->algo_data;
48 return au0828_read(dev, REG_201) & 0x02 ? 0 : 1;
51 static int i2c_wait_read_ack(struct i2c_adapter *i2c_adap)
55 for (count = 0; count < I2C_WAIT_RETRY; count++) {
56 if (!i2c_slave_did_read_ack(i2c_adap))
58 udelay(I2C_WAIT_DELAY);
61 if (I2C_WAIT_RETRY == count)
67 static inline int i2c_is_read_busy(struct i2c_adapter *i2c_adap)
69 struct au0828_dev *dev = i2c_adap->algo_data;
70 return au0828_read(dev, REG_201) & 0x01 ? 0 : 1;
73 static int i2c_wait_read_done(struct i2c_adapter *i2c_adap)
77 for (count = 0; count < I2C_WAIT_RETRY; count++) {
78 if (!i2c_is_read_busy(i2c_adap))
80 udelay(I2C_WAIT_DELAY);
83 if (I2C_WAIT_RETRY == count)
89 static inline int i2c_is_write_done(struct i2c_adapter *i2c_adap)
91 struct au0828_dev *dev = i2c_adap->algo_data;
92 return au0828_read(dev, REG_201) & 0x04 ? 1 : 0;
95 static int i2c_wait_write_done(struct i2c_adapter *i2c_adap)
99 for (count = 0; count < I2C_WAIT_RETRY; count++) {
100 if (i2c_is_write_done(i2c_adap))
102 udelay(I2C_WAIT_DELAY);
105 if (I2C_WAIT_RETRY == count)
111 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
113 struct au0828_dev *dev = i2c_adap->algo_data;
114 return au0828_read(dev, REG_201) & 0x10 ? 1 : 0;
117 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
121 for (count = 0; count < I2C_WAIT_RETRY; count++) {
122 if (!i2c_is_busy(i2c_adap))
124 udelay(I2C_WAIT_DELAY);
127 if (I2C_WAIT_RETRY == count)
133 /* FIXME: Implement join handling correctly */
134 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
135 const struct i2c_msg *msg, int joined_rlen)
138 struct au0828_dev *dev = i2c_adap->algo_data;
140 dprintk(4, "%s()\n", __func__);
142 au0828_write(dev, REG_2FF, 0x01);
144 /* FIXME: There is a problem with i2c communications with xc5000 that
145 requires us to slow down the i2c clock until we have a better
146 strategy (such as using the secondary i2c bus to do firmware
148 if ((msg->addr << 1) == 0xc2)
149 au0828_write(dev, REG_202, 0x40);
151 au0828_write(dev, REG_202, 0x07);
153 /* Hardware needs 8 bit addresses */
154 au0828_write(dev, REG_203, msg->addr << 1);
156 dprintk(4, "SEND: %02x\n", msg->addr);
158 /* Deal with i2c_scan */
160 /* The analog tuner detection code makes use of the SMBUS_QUICK
161 message (which involves a zero length i2c write). To avoid
162 checking the status register when we didn't strobe out any
163 actual bytes to the bus, just do a read check. This is
164 consistent with how I saw i2c device checking done in the
165 USB trace of the Windows driver */
166 au0828_write(dev, REG_200, 0x20);
167 if (!i2c_wait_done(i2c_adap))
170 if (i2c_wait_read_ack(i2c_adap))
176 for (i = 0; i < msg->len;) {
178 dprintk(4, " %02x\n", msg->buf[i]);
180 au0828_write(dev, REG_205, msg->buf[i]);
185 if ((strobe >= 4) || (i >= msg->len)) {
187 /* Strobe the byte into the bus */
189 au0828_write(dev, REG_200, 0x41);
191 au0828_write(dev, REG_200, 0x01);
193 /* Reset strobe trigger */
196 if (!i2c_wait_write_done(i2c_adap))
202 if (!i2c_wait_done(i2c_adap))
210 /* FIXME: Implement join handling correctly */
211 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
212 const struct i2c_msg *msg, int joined)
214 struct au0828_dev *dev = i2c_adap->algo_data;
217 dprintk(4, "%s()\n", __func__);
219 au0828_write(dev, REG_2FF, 0x01);
221 /* FIXME: There is a problem with i2c communications with xc5000 that
222 requires us to slow down the i2c clock until we have a better
223 strategy (such as using the secondary i2c bus to do firmware
225 if ((msg->addr << 1) == 0xc2)
226 au0828_write(dev, REG_202, 0x40);
228 au0828_write(dev, REG_202, 0x07);
230 /* Hardware needs 8 bit addresses */
231 au0828_write(dev, REG_203, msg->addr << 1);
233 dprintk(4, " RECV:\n");
235 /* Deal with i2c_scan */
237 au0828_write(dev, REG_200, 0x20);
238 if (i2c_wait_read_ack(i2c_adap))
243 for (i = 0; i < msg->len;) {
248 au0828_write(dev, REG_200, 0x60);
250 au0828_write(dev, REG_200, 0x20);
252 if (!i2c_wait_read_done(i2c_adap))
255 msg->buf[i-1] = au0828_read(dev, REG_209) & 0xff;
257 dprintk(4, " %02x\n", msg->buf[i-1]);
259 if (!i2c_wait_done(i2c_adap))
267 static int i2c_xfer(struct i2c_adapter *i2c_adap,
268 struct i2c_msg *msgs, int num)
272 dprintk(4, "%s(num = %d)\n", __func__, num);
274 for (i = 0; i < num; i++) {
275 dprintk(4, "%s(num = %d) addr = 0x%02x len = 0x%x\n",
276 __func__, num, msgs[i].addr, msgs[i].len);
277 if (msgs[i].flags & I2C_M_RD) {
279 retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
280 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
281 msgs[i].addr == msgs[i + 1].addr) {
282 /* write then read from same address */
283 retval = i2c_sendbytes(i2c_adap, &msgs[i],
288 retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
291 retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
302 static u32 au0828_functionality(struct i2c_adapter *adap)
304 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
307 static struct i2c_algorithm au0828_i2c_algo_template = {
308 .master_xfer = i2c_xfer,
309 .functionality = au0828_functionality,
312 /* ----------------------------------------------------------------------- */
314 static struct i2c_adapter au0828_i2c_adap_template = {
316 .owner = THIS_MODULE,
317 .id = I2C_HW_B_AU0828,
318 .algo = &au0828_i2c_algo_template,
321 static struct i2c_client au0828_i2c_client_template = {
322 .name = "au0828 internal",
325 static char *i2c_devs[128] = {
326 [0x8e >> 1] = "au8522",
327 [0xa0 >> 1] = "eeprom",
328 [0xc2 >> 1] = "tuner/xc5000",
331 static void do_i2c_scan(char *name, struct i2c_client *c)
336 for (i = 0; i < 128; i++) {
338 rc = i2c_master_recv(c, &buf, 0);
341 printk(KERN_INFO "%s: i2c scan: found device @ 0x%x [%s]\n",
342 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
346 /* init + register i2c algo-bit adapter */
347 int au0828_i2c_register(struct au0828_dev *dev)
349 dprintk(1, "%s()\n", __func__);
351 memcpy(&dev->i2c_adap, &au0828_i2c_adap_template,
352 sizeof(dev->i2c_adap));
353 memcpy(&dev->i2c_algo, &au0828_i2c_algo_template,
354 sizeof(dev->i2c_algo));
355 memcpy(&dev->i2c_client, &au0828_i2c_client_template,
356 sizeof(dev->i2c_client));
358 dev->i2c_adap.dev.parent = &dev->usbdev->dev;
360 strlcpy(dev->i2c_adap.name, DRIVER_NAME,
361 sizeof(dev->i2c_adap.name));
363 dev->i2c_adap.algo = &dev->i2c_algo;
364 dev->i2c_adap.algo_data = dev;
365 i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
366 i2c_add_adapter(&dev->i2c_adap);
368 dev->i2c_client.adapter = &dev->i2c_adap;
370 if (0 == dev->i2c_rc) {
371 printk(KERN_INFO "%s: i2c bus registered\n", DRIVER_NAME);
373 do_i2c_scan(DRIVER_NAME, &dev->i2c_client);
375 printk(KERN_INFO "%s: i2c bus register FAILED\n", DRIVER_NAME);
380 int au0828_i2c_unregister(struct au0828_dev *dev)
382 i2c_del_adapter(&dev->i2c_adap);