1/* 2 * Driver for the Conexant CX25821 PCIe bridge 3 * 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 7 * 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. 12 * 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 16 * 17 * GNU General Public License for more details. 18 * 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. 22 */ 23 24#include "cx25821.h" 25#include <linux/i2c.h> 26 27static unsigned int i2c_debug; 28module_param(i2c_debug, int, 0644); 29MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]"); 30 31static unsigned int i2c_scan; 32module_param(i2c_scan, int, 0444); 33MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time"); 34 35#define dprintk(level, fmt, arg...)\ 36 do { if (i2c_debug >= level)\ 37 printk(KERN_DEBUG "%s/0: " fmt, dev->name, ## arg);\ 38 } while (0) 39 40#define I2C_WAIT_DELAY 32 41#define I2C_WAIT_RETRY 64 42 43#define I2C_EXTEND (1 << 3) 44#define I2C_NOSTOP (1 << 4) 45 46static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap) 47{ 48 struct cx25821_i2c *bus = i2c_adap->algo_data; 49 struct cx25821_dev *dev = bus->dev; 50 return cx_read(bus->reg_stat) & 0x01; 51} 52 53static inline int i2c_is_busy(struct i2c_adapter *i2c_adap) 54{ 55 struct cx25821_i2c *bus = i2c_adap->algo_data; 56 struct cx25821_dev *dev = bus->dev; 57 return cx_read(bus->reg_stat) & 0x02 ? 1 : 0; 58} 59 60static int i2c_wait_done(struct i2c_adapter *i2c_adap) 61{ 62 int count; 63 64 for (count = 0; count < I2C_WAIT_RETRY; count++) { 65 if (!i2c_is_busy(i2c_adap)) 66 break; 67 udelay(I2C_WAIT_DELAY); 68 } 69 70 if (I2C_WAIT_RETRY == count) 71 return 0; 72 73 return 1; 74} 75 76static int i2c_sendbytes(struct i2c_adapter *i2c_adap, 77 const struct i2c_msg *msg, int joined_rlen) 78{ 79 struct cx25821_i2c *bus = i2c_adap->algo_data; 80 struct cx25821_dev *dev = bus->dev; 81 u32 wdata, addr, ctrl; 82 int retval, cnt; 83 84 if (joined_rlen) 85 dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__, 86 msg->len, joined_rlen); 87 else 88 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len); 89 90 /* Deal with i2c probe functions with zero payload */ 91 if (msg->len == 0) { 92 cx_write(bus->reg_addr, msg->addr << 25); 93 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2)); 94 95 if (!i2c_wait_done(i2c_adap)) 96 return -EIO; 97 98 if (!i2c_slave_did_ack(i2c_adap)) 99 return -EIO; 100 101 dprintk(1, "%s() returns 0\n", __func__); 102 return 0; 103 } 104 105 /* dev, reg + first byte */ 106 addr = (msg->addr << 25) | msg->buf[0]; 107 wdata = msg->buf[0]; 108 109 ctrl = bus->i2c_period | (1 << 12) | (1 << 2); 110 111 if (msg->len > 1) 112 ctrl |= I2C_NOSTOP | I2C_EXTEND; 113 else if (joined_rlen) 114 ctrl |= I2C_NOSTOP; 115 116 cx_write(bus->reg_addr, addr); 117 cx_write(bus->reg_wdata, wdata); 118 cx_write(bus->reg_ctrl, ctrl); 119 120 retval = i2c_wait_done(i2c_adap); 121 if (retval < 0) 122 goto err; 123 124 if (retval == 0) 125 goto eio; 126 127 if (i2c_debug) { 128 if (!(ctrl & I2C_NOSTOP)) 129 printk(" >\n"); 130 } 131 132 for (cnt = 1; cnt < msg->len; cnt++) { 133 /* following bytes */ 134 wdata = msg->buf[cnt]; 135 ctrl = bus->i2c_period | (1 << 12) | (1 << 2); 136 137 if (cnt < msg->len - 1) 138 ctrl |= I2C_NOSTOP | I2C_EXTEND; 139 else if (joined_rlen) 140 ctrl |= I2C_NOSTOP; 141 142 cx_write(bus->reg_addr, addr); 143 cx_write(bus->reg_wdata, wdata); 144 cx_write(bus->reg_ctrl, ctrl); 145 146 retval = i2c_wait_done(i2c_adap); 147 if (retval < 0) 148 goto err; 149 150 if (retval == 0) 151 goto eio; 152 153 if (i2c_debug) { 154 dprintk(1, " %02x", msg->buf[cnt]); 155 if (!(ctrl & I2C_NOSTOP)) 156 dprintk(1, " >\n"); 157 } 158 } 159 160 return msg->len; 161 162eio: 163 retval = -EIO; 164err: 165 if (i2c_debug) 166 printk(KERN_ERR " ERR: %d\n", retval); 167 return retval; 168} 169 170static int i2c_readbytes(struct i2c_adapter *i2c_adap, 171 const struct i2c_msg *msg, int joined) 172{ 173 struct cx25821_i2c *bus = i2c_adap->algo_data; 174 struct cx25821_dev *dev = bus->dev; 175 u32 ctrl, cnt; 176 int retval; 177 178 if (i2c_debug && !joined) 179 dprintk(1, "6-%s(msg->len=%d)\n", __func__, msg->len); 180 181 /* Deal with i2c probe functions with zero payload */ 182 if (msg->len == 0) { 183 cx_write(bus->reg_addr, msg->addr << 25); 184 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1); 185 if (!i2c_wait_done(i2c_adap)) 186 return -EIO; 187 if (!i2c_slave_did_ack(i2c_adap)) 188 return -EIO; 189 190 dprintk(1, "%s() returns 0\n", __func__); 191 return 0; 192 } 193 194 if (i2c_debug) { 195 if (joined) 196 dprintk(1, " R"); 197 else 198 dprintk(1, " <R %02x", (msg->addr << 1) + 1); 199 } 200 201 for (cnt = 0; cnt < msg->len; cnt++) { 202 203 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1; 204 205 if (cnt < msg->len - 1) 206 ctrl |= I2C_NOSTOP | I2C_EXTEND; 207 208 cx_write(bus->reg_addr, msg->addr << 25); 209 cx_write(bus->reg_ctrl, ctrl); 210 211 retval = i2c_wait_done(i2c_adap); 212 if (retval < 0) 213 goto err; 214 if (retval == 0) 215 goto eio; 216 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff; 217 218 if (i2c_debug) { 219 dprintk(1, " %02x", msg->buf[cnt]); 220 if (!(ctrl & I2C_NOSTOP)) 221 dprintk(1, " >\n"); 222 } 223 } 224 225 return msg->len; 226eio: 227 retval = -EIO; 228err: 229 if (i2c_debug) 230 printk(KERN_ERR " ERR: %d\n", retval); 231 return retval; 232} 233 234static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num) 235{ 236 struct cx25821_i2c *bus = i2c_adap->algo_data; 237 struct cx25821_dev *dev = bus->dev; 238 int i, retval = 0; 239 240 dprintk(1, "%s(num = %d)\n", __func__, num); 241 242 for (i = 0; i < num; i++) { 243 dprintk(1, "%s(num = %d) addr = 0x%02x len = 0x%x\n", 244 __func__, num, msgs[i].addr, msgs[i].len); 245 246 if (msgs[i].flags & I2C_M_RD) { 247 /* read */ 248 retval = i2c_readbytes(i2c_adap, &msgs[i], 0); 249 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) && 250 msgs[i].addr == msgs[i + 1].addr) { 251 /* write then read from same address */ 252 retval = 253 i2c_sendbytes(i2c_adap, &msgs[i], msgs[i + 1].len); 254 255 if (retval < 0) 256 goto err; 257 i++; 258 retval = i2c_readbytes(i2c_adap, &msgs[i], 1); 259 } else { 260 /* write */ 261 retval = i2c_sendbytes(i2c_adap, &msgs[i], 0); 262 } 263 264 if (retval < 0) 265 goto err; 266 } 267 return num; 268 269err: 270 return retval; 271} 272 273 274static u32 cx25821_functionality(struct i2c_adapter *adap) 275{ 276 return I2C_FUNC_SMBUS_EMUL | 277 I2C_FUNC_I2C | 278 I2C_FUNC_SMBUS_WORD_DATA | 279 I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA; 280} 281 282static struct i2c_algorithm cx25821_i2c_algo_template = { 283 .master_xfer = i2c_xfer, 284 .functionality = cx25821_functionality, 285#ifdef NEED_ALGO_CONTROL 286 .algo_control = dummy_algo_control, 287#endif 288}; 289 290static struct i2c_adapter cx25821_i2c_adap_template = { 291 .name = "cx25821", 292 .owner = THIS_MODULE, 293 .algo = &cx25821_i2c_algo_template, 294}; 295 296static struct i2c_client cx25821_i2c_client_template = { 297 .name = "cx25821 internal", 298}; 299 300/* init + register i2c algo-bit adapter */ 301int cx25821_i2c_register(struct cx25821_i2c *bus) 302{ 303 struct cx25821_dev *dev = bus->dev; 304 305 dprintk(1, "%s(bus = %d)\n", __func__, bus->nr); 306 307 memcpy(&bus->i2c_adap, &cx25821_i2c_adap_template, 308 sizeof(bus->i2c_adap)); 309 memcpy(&bus->i2c_algo, &cx25821_i2c_algo_template, 310 sizeof(bus->i2c_algo)); 311 memcpy(&bus->i2c_client, &cx25821_i2c_client_template, 312 sizeof(bus->i2c_client)); 313 314 bus->i2c_adap.dev.parent = &dev->pci->dev; 315 316 strlcpy(bus->i2c_adap.name, bus->dev->name, sizeof(bus->i2c_adap.name)); 317 318 bus->i2c_algo.data = bus; 319 bus->i2c_adap.algo_data = bus; 320 i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev); 321 i2c_add_adapter(&bus->i2c_adap); 322 323 bus->i2c_client.adapter = &bus->i2c_adap; 324 325 /* set up the I2c */ 326 bus->i2c_client.addr = (0x88 >> 1); 327 328 return bus->i2c_rc; 329} 330 331int cx25821_i2c_unregister(struct cx25821_i2c *bus) 332{ 333 i2c_del_adapter(&bus->i2c_adap); 334 return 0; 335} 336 337void cx25821_av_clk(struct cx25821_dev *dev, int enable) 338{ 339 /* write 0 to bus 2 addr 0x144 via i2x_xfer() */ 340 char buffer[3]; 341 struct i2c_msg msg; 342 dprintk(1, "%s(enabled = %d)\n", __func__, enable); 343 344 /* Register 0x144 */ 345 buffer[0] = 0x01; 346 buffer[1] = 0x44; 347 if (enable == 1) 348 buffer[2] = 0x05; 349 else 350 buffer[2] = 0x00; 351 352 msg.addr = 0x44; 353 msg.flags = I2C_M_TEN; 354 msg.len = 3; 355 msg.buf = buffer; 356 357 i2c_xfer(&dev->i2c_bus[0].i2c_adap, &msg, 1); 358} 359 360int cx25821_i2c_read(struct cx25821_i2c *bus, u16 reg_addr, int *value) 361{ 362 struct i2c_client *client = &bus->i2c_client; 363 int retval = 0; 364 int v = 0; 365 u8 addr[2] = { 0, 0 }; 366 u8 buf[4] = { 0, 0, 0, 0 }; 367 368 struct i2c_msg msgs[2] = { 369 { 370 .addr = client->addr, 371 .flags = 0, 372 .len = 2, 373 .buf = addr, 374 }, { 375 .addr = client->addr, 376 .flags = I2C_M_RD, 377 .len = 4, 378 .buf = buf, 379 } 380 }; 381 382 addr[0] = (reg_addr >> 8); 383 addr[1] = (reg_addr & 0xff); 384 msgs[0].addr = 0x44; 385 msgs[1].addr = 0x44; 386 387 retval = i2c_xfer(client->adapter, msgs, 2); 388 389 v = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0]; 390 *value = v; 391 392 return v; 393} 394 395int cx25821_i2c_write(struct cx25821_i2c *bus, u16 reg_addr, int value) 396{ 397 struct i2c_client *client = &bus->i2c_client; 398 int retval = 0; 399 u8 buf[6] = { 0, 0, 0, 0, 0, 0 }; 400 401 struct i2c_msg msgs[1] = { 402 { 403 .addr = client->addr, 404 .flags = 0, 405 .len = 6, 406 .buf = buf, 407 } 408 }; 409 410 buf[0] = reg_addr >> 8; 411 buf[1] = reg_addr & 0xff; 412 buf[5] = (value >> 24) & 0xff; 413 buf[4] = (value >> 16) & 0xff; 414 buf[3] = (value >> 8) & 0xff; 415 buf[2] = value & 0xff; 416 client->flags = 0; 417 msgs[0].addr = 0x44; 418 419 retval = i2c_xfer(client->adapter, msgs, 1); 420 421 return retval; 422} 423