2 * Driver for the Conexant CX25821 PCIe bridge
4 * Copyright (C) 2009 Conexant Systems Inc.
5 * Authors <shu.lin@conexant.com>, <hiep.huynh@conexant.com>
6 * Based on Steven Toth <stoth@linuxtv.org> cx23885 driver
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27 #include <linux/i2c.h>
29 static unsigned int i2c_debug;
30 module_param(i2c_debug, int, 0644);
31 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
33 static unsigned int i2c_scan;
34 module_param(i2c_scan, int, 0444);
35 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
37 #define dprintk(level, fmt, arg...) \
39 if (i2c_debug >= level) \
40 printk(KERN_DEBUG "%s/0: " fmt, dev->name, ##arg); \
43 #define I2C_WAIT_DELAY 32
44 #define I2C_WAIT_RETRY 64
46 #define I2C_EXTEND (1 << 3)
47 #define I2C_NOSTOP (1 << 4)
49 static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
51 struct cx25821_i2c *bus = i2c_adap->algo_data;
52 struct cx25821_dev *dev = bus->dev;
53 return cx_read(bus->reg_stat) & 0x01;
56 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
58 struct cx25821_i2c *bus = i2c_adap->algo_data;
59 struct cx25821_dev *dev = bus->dev;
60 return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
63 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
67 for (count = 0; count < I2C_WAIT_RETRY; count++) {
68 if (!i2c_is_busy(i2c_adap))
70 udelay(I2C_WAIT_DELAY);
73 if (I2C_WAIT_RETRY == count)
79 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
80 const struct i2c_msg *msg, int joined_rlen)
82 struct cx25821_i2c *bus = i2c_adap->algo_data;
83 struct cx25821_dev *dev = bus->dev;
84 u32 wdata, addr, ctrl;
88 dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__,
89 msg->len, joined_rlen);
91 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
93 /* Deal with i2c probe functions with zero payload */
95 cx_write(bus->reg_addr, msg->addr << 25);
96 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
98 if (!i2c_wait_done(i2c_adap))
101 if (!i2c_slave_did_ack(i2c_adap))
104 dprintk(1, "%s(): returns 0\n", __func__);
108 /* dev, reg + first byte */
109 addr = (msg->addr << 25) | msg->buf[0];
112 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
115 ctrl |= I2C_NOSTOP | I2C_EXTEND;
116 else if (joined_rlen)
119 cx_write(bus->reg_addr, addr);
120 cx_write(bus->reg_wdata, wdata);
121 cx_write(bus->reg_ctrl, ctrl);
123 retval = i2c_wait_done(i2c_adap);
131 if (!(ctrl & I2C_NOSTOP))
135 for (cnt = 1; cnt < msg->len; cnt++) {
136 /* following bytes */
137 wdata = msg->buf[cnt];
138 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
140 if (cnt < msg->len - 1)
141 ctrl |= I2C_NOSTOP | I2C_EXTEND;
142 else if (joined_rlen)
145 cx_write(bus->reg_addr, addr);
146 cx_write(bus->reg_wdata, wdata);
147 cx_write(bus->reg_ctrl, ctrl);
149 retval = i2c_wait_done(i2c_adap);
157 dprintk(1, " %02x", msg->buf[cnt]);
158 if (!(ctrl & I2C_NOSTOP))
169 pr_err(" ERR: %d\n", retval);
173 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
174 const struct i2c_msg *msg, int joined)
176 struct cx25821_i2c *bus = i2c_adap->algo_data;
177 struct cx25821_dev *dev = bus->dev;
181 if (i2c_debug && !joined)
182 dprintk(1, "6-%s(msg->len=%d)\n", __func__, msg->len);
184 /* Deal with i2c probe functions with zero payload */
186 cx_write(bus->reg_addr, msg->addr << 25);
187 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
188 if (!i2c_wait_done(i2c_adap))
190 if (!i2c_slave_did_ack(i2c_adap))
193 dprintk(1, "%s(): returns 0\n", __func__);
201 dprintk(1, " <R %02x", (msg->addr << 1) + 1);
204 for (cnt = 0; cnt < msg->len; cnt++) {
206 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
208 if (cnt < msg->len - 1)
209 ctrl |= I2C_NOSTOP | I2C_EXTEND;
211 cx_write(bus->reg_addr, msg->addr << 25);
212 cx_write(bus->reg_ctrl, ctrl);
214 retval = i2c_wait_done(i2c_adap);
219 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
222 dprintk(1, " %02x", msg->buf[cnt]);
223 if (!(ctrl & I2C_NOSTOP))
233 pr_err(" ERR: %d\n", retval);
237 static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
239 struct cx25821_i2c *bus = i2c_adap->algo_data;
240 struct cx25821_dev *dev = bus->dev;
243 dprintk(1, "%s(num = %d)\n", __func__, num);
245 for (i = 0; i < num; i++) {
246 dprintk(1, "%s(num = %d) addr = 0x%02x len = 0x%x\n",
247 __func__, num, msgs[i].addr, msgs[i].len);
249 if (msgs[i].flags & I2C_M_RD) {
251 retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
252 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
253 msgs[i].addr == msgs[i + 1].addr) {
254 /* write then read from same address */
255 retval = i2c_sendbytes(i2c_adap, &msgs[i],
261 retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
264 retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
277 static u32 cx25821_functionality(struct i2c_adapter *adap)
279 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C | I2C_FUNC_SMBUS_WORD_DATA |
280 I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA;
283 static struct i2c_algorithm cx25821_i2c_algo_template = {
284 .master_xfer = i2c_xfer,
285 .functionality = cx25821_functionality,
286 #ifdef NEED_ALGO_CONTROL
287 .algo_control = dummy_algo_control,
291 static struct i2c_adapter cx25821_i2c_adap_template = {
293 .owner = THIS_MODULE,
294 .algo = &cx25821_i2c_algo_template,
297 static struct i2c_client cx25821_i2c_client_template = {
298 .name = "cx25821 internal",
301 /* init + register i2c adapter */
302 int cx25821_i2c_register(struct cx25821_i2c *bus)
304 struct cx25821_dev *dev = bus->dev;
306 dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
308 bus->i2c_adap = cx25821_i2c_adap_template;
309 bus->i2c_client = cx25821_i2c_client_template;
310 bus->i2c_adap.dev.parent = &dev->pci->dev;
312 strlcpy(bus->i2c_adap.name, bus->dev->name, sizeof(bus->i2c_adap.name));
314 bus->i2c_adap.algo_data = bus;
315 i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
316 i2c_add_adapter(&bus->i2c_adap);
318 bus->i2c_client.adapter = &bus->i2c_adap;
321 bus->i2c_client.addr = (0x88 >> 1);
326 int cx25821_i2c_unregister(struct cx25821_i2c *bus)
328 i2c_del_adapter(&bus->i2c_adap);
332 void cx25821_av_clk(struct cx25821_dev *dev, int enable)
334 /* write 0 to bus 2 addr 0x144 via i2x_xfer() */
337 dprintk(1, "%s(enabled = %d)\n", __func__, enable);
348 msg.flags = I2C_M_TEN;
352 i2c_xfer(&dev->i2c_bus[0].i2c_adap, &msg, 1);
355 int cx25821_i2c_read(struct cx25821_i2c *bus, u16 reg_addr, int *value)
357 struct i2c_client *client = &bus->i2c_client;
359 u8 addr[2] = { 0, 0 };
360 u8 buf[4] = { 0, 0, 0, 0 };
362 struct i2c_msg msgs[2] = {
364 .addr = client->addr,
369 .addr = client->addr,
376 addr[0] = (reg_addr >> 8);
377 addr[1] = (reg_addr & 0xff);
381 i2c_xfer(client->adapter, msgs, 2);
383 v = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
389 int cx25821_i2c_write(struct cx25821_i2c *bus, u16 reg_addr, int value)
391 struct i2c_client *client = &bus->i2c_client;
393 u8 buf[6] = { 0, 0, 0, 0, 0, 0 };
395 struct i2c_msg msgs[1] = {
397 .addr = client->addr,
404 buf[0] = reg_addr >> 8;
405 buf[1] = reg_addr & 0xff;
406 buf[5] = (value >> 24) & 0xff;
407 buf[4] = (value >> 16) & 0xff;
408 buf[3] = (value >> 8) & 0xff;
409 buf[2] = value & 0xff;
413 retval = i2c_xfer(client->adapter, msgs, 1);