1 /* 2 * Driver for the Auvitek AU0828 USB bridge 3 * 4 * Copyright (c) 2008 Steven Toth <stoth@linuxtv.org> 5 * 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. 10 * 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 14 * 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., 675 Mass Ave, Cambridge, MA 02139, USA. 20 */ 21 22 #include "au0828.h" 23 24 #include <linux/module.h> 25 #include <linux/moduleparam.h> 26 #include <linux/init.h> 27 #include <linux/delay.h> 28 #include <linux/io.h> 29 30 #include "media/tuner.h" 31 #include <media/v4l2-common.h> 32 33 static int i2c_scan; 34 module_param(i2c_scan, int, 0444); 35 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time"); 36 37 #define I2C_WAIT_DELAY 25 38 #define I2C_WAIT_RETRY 1000 39 40 static inline int i2c_slave_did_write_ack(struct i2c_adapter *i2c_adap) 41 { 42 struct au0828_dev *dev = i2c_adap->algo_data; 43 return au0828_read(dev, AU0828_I2C_STATUS_201) & 44 AU0828_I2C_STATUS_NO_WRITE_ACK ? 0 : 1; 45 } 46 47 static inline int i2c_slave_did_read_ack(struct i2c_adapter *i2c_adap) 48 { 49 struct au0828_dev *dev = i2c_adap->algo_data; 50 return au0828_read(dev, AU0828_I2C_STATUS_201) & 51 AU0828_I2C_STATUS_NO_READ_ACK ? 0 : 1; 52 } 53 54 static int i2c_wait_read_ack(struct i2c_adapter *i2c_adap) 55 { 56 int count; 57 58 for (count = 0; count < I2C_WAIT_RETRY; count++) { 59 if (!i2c_slave_did_read_ack(i2c_adap)) 60 break; 61 udelay(I2C_WAIT_DELAY); 62 } 63 64 if (I2C_WAIT_RETRY == count) 65 return 0; 66 67 return 1; 68 } 69 70 static inline int i2c_is_read_busy(struct i2c_adapter *i2c_adap) 71 { 72 struct au0828_dev *dev = i2c_adap->algo_data; 73 return au0828_read(dev, AU0828_I2C_STATUS_201) & 74 AU0828_I2C_STATUS_READ_DONE ? 0 : 1; 75 } 76 77 static int i2c_wait_read_done(struct i2c_adapter *i2c_adap) 78 { 79 int count; 80 81 for (count = 0; count < I2C_WAIT_RETRY; count++) { 82 if (!i2c_is_read_busy(i2c_adap)) 83 break; 84 udelay(I2C_WAIT_DELAY); 85 } 86 87 if (I2C_WAIT_RETRY == count) 88 return 0; 89 90 return 1; 91 } 92 93 static inline int i2c_is_write_done(struct i2c_adapter *i2c_adap) 94 { 95 struct au0828_dev *dev = i2c_adap->algo_data; 96 return au0828_read(dev, AU0828_I2C_STATUS_201) & 97 AU0828_I2C_STATUS_WRITE_DONE ? 1 : 0; 98 } 99 100 static int i2c_wait_write_done(struct i2c_adapter *i2c_adap) 101 { 102 int count; 103 104 for (count = 0; count < I2C_WAIT_RETRY; count++) { 105 if (i2c_is_write_done(i2c_adap)) 106 break; 107 udelay(I2C_WAIT_DELAY); 108 } 109 110 if (I2C_WAIT_RETRY == count) 111 return 0; 112 113 return 1; 114 } 115 116 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap) 117 { 118 struct au0828_dev *dev = i2c_adap->algo_data; 119 return au0828_read(dev, AU0828_I2C_STATUS_201) & 120 AU0828_I2C_STATUS_BUSY ? 1 : 0; 121 } 122 123 static int i2c_wait_done(struct i2c_adapter *i2c_adap) 124 { 125 int count; 126 127 for (count = 0; count < I2C_WAIT_RETRY; count++) { 128 if (!i2c_is_busy(i2c_adap)) 129 break; 130 udelay(I2C_WAIT_DELAY); 131 } 132 133 if (I2C_WAIT_RETRY == count) 134 return 0; 135 136 return 1; 137 } 138 139 /* FIXME: Implement join handling correctly */ 140 static int i2c_sendbytes(struct i2c_adapter *i2c_adap, 141 const struct i2c_msg *msg, int joined_rlen) 142 { 143 int i, strobe = 0; 144 struct au0828_dev *dev = i2c_adap->algo_data; 145 u8 i2c_speed = dev->board.i2c_clk_divider; 146 147 dprintk(4, "%s()\n", __func__); 148 149 au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01); 150 151 if (((dev->board.tuner_type == TUNER_XC5000) || 152 (dev->board.tuner_type == TUNER_XC5000C)) && 153 (dev->board.tuner_addr == msg->addr)) { 154 /* 155 * Due to I2C clock stretch, we need to use a lower speed 156 * on xc5000 for commands. However, firmware transfer can 157 * speed up to 400 KHz. 158 */ 159 if (msg->len == 64) 160 i2c_speed = AU0828_I2C_CLK_250KHZ; 161 else 162 i2c_speed = AU0828_I2C_CLK_20KHZ; 163 } 164 /* Set the I2C clock */ 165 au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, i2c_speed); 166 167 /* Hardware needs 8 bit addresses */ 168 au0828_write(dev, AU0828_I2C_DEST_ADDR_203, msg->addr << 1); 169 170 dprintk(4, "SEND: %02x\n", msg->addr); 171 172 /* Deal with i2c_scan */ 173 if (msg->len == 0) { 174 /* The analog tuner detection code makes use of the SMBUS_QUICK 175 message (which involves a zero length i2c write). To avoid 176 checking the status register when we didn't strobe out any 177 actual bytes to the bus, just do a read check. This is 178 consistent with how I saw i2c device checking done in the 179 USB trace of the Windows driver */ 180 au0828_write(dev, AU0828_I2C_TRIGGER_200, 181 AU0828_I2C_TRIGGER_READ); 182 183 if (!i2c_wait_done(i2c_adap)) 184 return -EIO; 185 186 if (i2c_wait_read_ack(i2c_adap)) 187 return -EIO; 188 189 return 0; 190 } 191 192 for (i = 0; i < msg->len;) { 193 194 dprintk(4, " %02x\n", msg->buf[i]); 195 196 au0828_write(dev, AU0828_I2C_WRITE_FIFO_205, msg->buf[i]); 197 198 strobe++; 199 i++; 200 201 if ((strobe >= 4) || (i >= msg->len)) { 202 203 /* Strobe the byte into the bus */ 204 if (i < msg->len) 205 au0828_write(dev, AU0828_I2C_TRIGGER_200, 206 AU0828_I2C_TRIGGER_WRITE | 207 AU0828_I2C_TRIGGER_HOLD); 208 else 209 au0828_write(dev, AU0828_I2C_TRIGGER_200, 210 AU0828_I2C_TRIGGER_WRITE); 211 212 /* Reset strobe trigger */ 213 strobe = 0; 214 215 if (!i2c_wait_write_done(i2c_adap)) 216 return -EIO; 217 218 } 219 220 } 221 if (!i2c_wait_done(i2c_adap)) 222 return -EIO; 223 224 dprintk(4, "\n"); 225 226 return msg->len; 227 } 228 229 /* FIXME: Implement join handling correctly */ 230 static int i2c_readbytes(struct i2c_adapter *i2c_adap, 231 const struct i2c_msg *msg, int joined) 232 { 233 struct au0828_dev *dev = i2c_adap->algo_data; 234 u8 i2c_speed = dev->board.i2c_clk_divider; 235 int i; 236 237 dprintk(4, "%s()\n", __func__); 238 239 au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01); 240 241 /* 242 * Due to xc5000c clock stretch, we cannot use full speed at 243 * readings from xc5000, as otherwise they'll fail. 244 */ 245 if (((dev->board.tuner_type == TUNER_XC5000) || 246 (dev->board.tuner_type == TUNER_XC5000C)) && 247 (dev->board.tuner_addr == msg->addr)) 248 i2c_speed = AU0828_I2C_CLK_20KHZ; 249 250 /* Set the I2C clock */ 251 au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, i2c_speed); 252 253 /* Hardware needs 8 bit addresses */ 254 au0828_write(dev, AU0828_I2C_DEST_ADDR_203, msg->addr << 1); 255 256 dprintk(4, " RECV:\n"); 257 258 /* Deal with i2c_scan */ 259 if (msg->len == 0) { 260 au0828_write(dev, AU0828_I2C_TRIGGER_200, 261 AU0828_I2C_TRIGGER_READ); 262 263 if (i2c_wait_read_ack(i2c_adap)) 264 return -EIO; 265 return 0; 266 } 267 268 for (i = 0; i < msg->len;) { 269 270 i++; 271 272 if (i < msg->len) 273 au0828_write(dev, AU0828_I2C_TRIGGER_200, 274 AU0828_I2C_TRIGGER_READ | 275 AU0828_I2C_TRIGGER_HOLD); 276 else 277 au0828_write(dev, AU0828_I2C_TRIGGER_200, 278 AU0828_I2C_TRIGGER_READ); 279 280 if (!i2c_wait_read_done(i2c_adap)) 281 return -EIO; 282 283 msg->buf[i-1] = au0828_read(dev, AU0828_I2C_READ_FIFO_209) & 284 0xff; 285 286 dprintk(4, " %02x\n", msg->buf[i-1]); 287 } 288 if (!i2c_wait_done(i2c_adap)) 289 return -EIO; 290 291 dprintk(4, "\n"); 292 293 return msg->len; 294 } 295 296 static int i2c_xfer(struct i2c_adapter *i2c_adap, 297 struct i2c_msg *msgs, int num) 298 { 299 int i, retval = 0; 300 301 dprintk(4, "%s(num = %d)\n", __func__, num); 302 303 for (i = 0; i < num; i++) { 304 dprintk(4, "%s(num = %d) addr = 0x%02x len = 0x%x\n", 305 __func__, num, msgs[i].addr, msgs[i].len); 306 if (msgs[i].flags & I2C_M_RD) { 307 /* read */ 308 retval = i2c_readbytes(i2c_adap, &msgs[i], 0); 309 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) && 310 msgs[i].addr == msgs[i + 1].addr) { 311 /* write then read from same address */ 312 retval = i2c_sendbytes(i2c_adap, &msgs[i], 313 msgs[i + 1].len); 314 if (retval < 0) 315 goto err; 316 i++; 317 retval = i2c_readbytes(i2c_adap, &msgs[i], 1); 318 } else { 319 /* write */ 320 retval = i2c_sendbytes(i2c_adap, &msgs[i], 0); 321 } 322 if (retval < 0) 323 goto err; 324 } 325 return num; 326 327 err: 328 return retval; 329 } 330 331 static u32 au0828_functionality(struct i2c_adapter *adap) 332 { 333 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C; 334 } 335 336 static struct i2c_algorithm au0828_i2c_algo_template = { 337 .master_xfer = i2c_xfer, 338 .functionality = au0828_functionality, 339 }; 340 341 /* ----------------------------------------------------------------------- */ 342 343 static struct i2c_adapter au0828_i2c_adap_template = { 344 .name = KBUILD_MODNAME, 345 .owner = THIS_MODULE, 346 .algo = &au0828_i2c_algo_template, 347 }; 348 349 static struct i2c_client au0828_i2c_client_template = { 350 .name = "au0828 internal", 351 }; 352 353 static char *i2c_devs[128] = { 354 [0x8e >> 1] = "au8522", 355 [0xa0 >> 1] = "eeprom", 356 [0xc2 >> 1] = "tuner/xc5000", 357 }; 358 359 static void do_i2c_scan(char *name, struct i2c_client *c) 360 { 361 unsigned char buf; 362 int i, rc; 363 364 for (i = 0; i < 128; i++) { 365 c->addr = i; 366 rc = i2c_master_recv(c, &buf, 0); 367 if (rc < 0) 368 continue; 369 pr_info("%s: i2c scan: found device @ 0x%x [%s]\n", 370 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???"); 371 } 372 } 373 374 /* init + register i2c adapter */ 375 int au0828_i2c_register(struct au0828_dev *dev) 376 { 377 dprintk(1, "%s()\n", __func__); 378 379 dev->i2c_adap = au0828_i2c_adap_template; 380 dev->i2c_algo = au0828_i2c_algo_template; 381 dev->i2c_client = au0828_i2c_client_template; 382 383 dev->i2c_adap.dev.parent = &dev->usbdev->dev; 384 385 strlcpy(dev->i2c_adap.name, KBUILD_MODNAME, 386 sizeof(dev->i2c_adap.name)); 387 388 dev->i2c_adap.algo = &dev->i2c_algo; 389 dev->i2c_adap.algo_data = dev; 390 #ifdef CONFIG_VIDEO_AU0828_V4L2 391 i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev); 392 #else 393 i2c_set_adapdata(&dev->i2c_adap, dev); 394 #endif 395 i2c_add_adapter(&dev->i2c_adap); 396 397 dev->i2c_client.adapter = &dev->i2c_adap; 398 399 if (0 == dev->i2c_rc) { 400 pr_info("i2c bus registered\n"); 401 if (i2c_scan) 402 do_i2c_scan(KBUILD_MODNAME, &dev->i2c_client); 403 } else 404 pr_info("i2c bus register FAILED\n"); 405 406 return dev->i2c_rc; 407 } 408 409 int au0828_i2c_unregister(struct au0828_dev *dev) 410 { 411 i2c_del_adapter(&dev->i2c_adap); 412 return 0; 413 } 414 415