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