usbvision-i2c.c revision 1df795370c1392a026c63816368108187aec2ec1
1/* 2 * usbvision_i2c.c 3 * i2c algorithm for USB-I2C Bridges 4 * 5 * Copyright (c) 1999-2007 Joerg Heckenbach <joerg@heckenbach-aw.de> 6 * Dwaine Garden <dwainegarden@rogers.com> 7 * 8 * This module is part of usbvision driver project. 9 * Updates to driver completed by Dwaine P. Garden 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 24 */ 25 26 27#include <linux/kernel.h> 28#include <linux/module.h> 29#include <linux/delay.h> 30#include <linux/slab.h> 31#include <linux/version.h> 32#include <linux/utsname.h> 33#include <linux/init.h> 34#include <asm/uaccess.h> 35#include <linux/ioport.h> 36#include <linux/errno.h> 37#include <linux/usb.h> 38#include <linux/i2c.h> 39#include "usbvision.h" 40 41#define DBG_I2C 1<<0 42 43static int i2c_debug; 44 45module_param (i2c_debug, int, 0644); // debug_i2c_usb mode of the device driver 46MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]"); 47 48#define PDEBUG(level, fmt, args...) { \ 49 if (i2c_debug & (level)) \ 50 printk(KERN_INFO KBUILD_MODNAME ":[%s:%d] " fmt, \ 51 __func__, __LINE__ , ## args); \ 52 } 53 54static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf, 55 short len); 56static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf, 57 short len); 58 59static inline int try_write_address(struct i2c_adapter *i2c_adap, 60 unsigned char addr, int retries) 61{ 62 struct usb_usbvision *usbvision; 63 int i, ret = -1; 64 char buf[4]; 65 66 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap); 67 buf[0] = 0x00; 68 for (i = 0; i <= retries; i++) { 69 ret = (usbvision_i2c_write(usbvision, addr, buf, 1)); 70 if (ret == 1) 71 break; /* success! */ 72 udelay(5); 73 if (i == retries) /* no success */ 74 break; 75 udelay(10); 76 } 77 if (i) { 78 PDEBUG(DBG_I2C,"Needed %d retries for address %#2x", i, addr); 79 PDEBUG(DBG_I2C,"Maybe there's no device at this address"); 80 } 81 return ret; 82} 83 84static inline int try_read_address(struct i2c_adapter *i2c_adap, 85 unsigned char addr, int retries) 86{ 87 struct usb_usbvision *usbvision; 88 int i, ret = -1; 89 char buf[4]; 90 91 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap); 92 for (i = 0; i <= retries; i++) { 93 ret = (usbvision_i2c_read(usbvision, addr, buf, 1)); 94 if (ret == 1) 95 break; /* success! */ 96 udelay(5); 97 if (i == retries) /* no success */ 98 break; 99 udelay(10); 100 } 101 if (i) { 102 PDEBUG(DBG_I2C,"Needed %d retries for address %#2x", i, addr); 103 PDEBUG(DBG_I2C,"Maybe there's no device at this address"); 104 } 105 return ret; 106} 107 108static inline int usb_find_address(struct i2c_adapter *i2c_adap, 109 struct i2c_msg *msg, int retries, 110 unsigned char *add) 111{ 112 unsigned short flags = msg->flags; 113 114 unsigned char addr; 115 int ret; 116 if ((flags & I2C_M_TEN)) { 117 /* a ten bit address */ 118 addr = 0xf0 | ((msg->addr >> 7) & 0x03); 119 /* try extended address code... */ 120 ret = try_write_address(i2c_adap, addr, retries); 121 if (ret != 1) { 122 dev_err(&i2c_adap->dev, 123 "died at extended address code, while writing\n"); 124 return -EREMOTEIO; 125 } 126 add[0] = addr; 127 if (flags & I2C_M_RD) { 128 /* okay, now switch into reading mode */ 129 addr |= 0x01; 130 ret = try_read_address(i2c_adap, addr, retries); 131 if (ret != 1) { 132 dev_err(&i2c_adap->dev, 133 "died at extended address code, while reading\n"); 134 return -EREMOTEIO; 135 } 136 } 137 138 } else { /* normal 7bit address */ 139 addr = (msg->addr << 1); 140 if (flags & I2C_M_RD) 141 addr |= 1; 142 143 add[0] = addr; 144 if (flags & I2C_M_RD) 145 ret = try_read_address(i2c_adap, addr, retries); 146 else 147 ret = try_write_address(i2c_adap, addr, retries); 148 149 if (ret != 1) { 150 return -EREMOTEIO; 151 } 152 } 153 return 0; 154} 155 156static int 157usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num) 158{ 159 struct i2c_msg *pmsg; 160 struct usb_usbvision *usbvision; 161 int i, ret; 162 unsigned char addr = 0; 163 164 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap); 165 166 for (i = 0; i < num; i++) { 167 pmsg = &msgs[i]; 168 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr); 169 if (ret != 0) { 170 PDEBUG(DBG_I2C,"got NAK from device, message #%d", i); 171 return (ret < 0) ? ret : -EREMOTEIO; 172 } 173 174 if (pmsg->flags & I2C_M_RD) { 175 /* read bytes into buffer */ 176 ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len)); 177 if (ret < pmsg->len) { 178 return (ret < 0) ? ret : -EREMOTEIO; 179 } 180 } else { 181 /* write bytes from buffer */ 182 ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len)); 183 if (ret < pmsg->len) { 184 return (ret < 0) ? ret : -EREMOTEIO; 185 } 186 } 187 } 188 return num; 189} 190 191static u32 functionality(struct i2c_adapter *adap) 192{ 193 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; 194} 195 196/* -----exported algorithm data: ------------------------------------- */ 197 198static struct i2c_algorithm usbvision_algo = { 199 .master_xfer = usbvision_i2c_xfer, 200 .smbus_xfer = NULL, 201 .functionality = functionality, 202}; 203 204 205/* ----------------------------------------------------------------------- */ 206/* usbvision specific I2C functions */ 207/* ----------------------------------------------------------------------- */ 208static struct i2c_adapter i2c_adap_template; 209 210int usbvision_i2c_register(struct usb_usbvision *usbvision) 211{ 212 static unsigned short saa711x_addrs[] = { 213 0x4a >> 1, 0x48 >> 1, /* SAA7111, SAA7111A and SAA7113 */ 214 0x42 >> 1, 0x40 >> 1, /* SAA7114, SAA7115 and SAA7118 */ 215 I2C_CLIENT_END }; 216 217 memcpy(&usbvision->i2c_adap, &i2c_adap_template, 218 sizeof(struct i2c_adapter)); 219 220 sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name), 221 " #%d", usbvision->vdev->num); 222 PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name); 223 usbvision->i2c_adap.dev.parent = &usbvision->dev->dev; 224 225 i2c_set_adapdata(&usbvision->i2c_adap, &usbvision->v4l2_dev); 226 227 if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) { 228 printk(KERN_ERR "usbvision_register: can't write reg\n"); 229 return -EBUSY; 230 } 231 232 PDEBUG(DBG_I2C, "I2C debugging is enabled [i2c]"); 233 PDEBUG(DBG_I2C, "ALGO debugging is enabled [i2c]"); 234 235 /* register new adapter to i2c module... */ 236 237 usbvision->i2c_adap.algo = &usbvision_algo; 238 239 usbvision->i2c_adap.timeout = 100; /* default values, should */ 240 usbvision->i2c_adap.retries = 3; /* be replaced by defines */ 241 242 i2c_add_adapter(&usbvision->i2c_adap); 243 244 PDEBUG(DBG_I2C, "i2c bus for %s registered", usbvision->i2c_adap.name); 245 246 /* Request the load of the i2c modules we need */ 247 switch (usbvision_device_data[usbvision->DevModel].Codec) { 248 case CODEC_SAA7113: 249 case CODEC_SAA7111: 250 v4l2_i2c_new_probed_subdev(&usbvision->i2c_adap, "saa7115", 251 "saa7115_auto", saa711x_addrs); 252 break; 253 } 254 if (usbvision_device_data[usbvision->DevModel].Tuner == 1) { 255 struct v4l2_subdev *sd; 256 enum v4l2_i2c_tuner_type type; 257 struct tuner_setup tun_setup; 258 259 sd = v4l2_i2c_new_probed_subdev(&usbvision->i2c_adap, "tuner", 260 "tuner", v4l2_i2c_tuner_addrs(ADDRS_DEMOD)); 261 /* depending on whether we found a demod or not, select 262 the tuner type. */ 263 type = sd ? ADDRS_TV_WITH_DEMOD : ADDRS_TV; 264 265 sd = v4l2_i2c_new_probed_subdev(&usbvision->i2c_adap, "tuner", 266 "tuner", v4l2_i2c_tuner_addrs(type)); 267 268 if (usbvision->tuner_type != -1) { 269 tun_setup.mode_mask = T_ANALOG_TV | T_RADIO; 270 tun_setup.type = usbvision->tuner_type; 271 tun_setup.addr = v4l2_i2c_subdev_addr(sd); 272 call_all(usbvision, tuner, s_type_addr, &tun_setup); 273 } 274 } 275 276 return 0; 277} 278 279int usbvision_i2c_unregister(struct usb_usbvision *usbvision) 280{ 281 282 i2c_del_adapter(&(usbvision->i2c_adap)); 283 284 PDEBUG(DBG_I2C,"i2c bus for %s unregistered", usbvision->i2c_adap.name); 285 286 return 0; 287} 288 289static int 290usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr, 291 char *buf, short len) 292{ 293 int rc, retries; 294 295 for (retries = 5;;) { 296 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr); 297 if (rc < 0) 298 return rc; 299 300 /* Initiate byte read cycle */ 301 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */ 302 /* d3 0=Wr 1=Rd */ 303 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 304 (len & 0x07) | 0x18); 305 if (rc < 0) 306 return rc; 307 308 /* Test for Busy and ACK */ 309 do { 310 /* USBVISION_SER_CONT -> d4 == 0 busy */ 311 rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT); 312 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */ 313 if (rc < 0) 314 return rc; 315 316 /* USBVISION_SER_CONT -> d5 == 1 Not ack */ 317 if ((rc & 0x20) == 0) /* Ack? */ 318 break; 319 320 /* I2C abort */ 321 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00); 322 if (rc < 0) 323 return rc; 324 325 if (--retries < 0) 326 return -1; 327 } 328 329 switch (len) { 330 case 4: 331 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4); 332 case 3: 333 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3); 334 case 2: 335 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2); 336 case 1: 337 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1); 338 break; 339 default: 340 printk(KERN_ERR 341 "usbvision_i2c_read_max4: buffer length > 4\n"); 342 } 343 344 if (i2c_debug & DBG_I2C) { 345 int idx; 346 for (idx = 0; idx < len; idx++) { 347 PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr); 348 } 349 } 350 return len; 351} 352 353 354static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision, 355 unsigned char addr, const char *buf, 356 short len) 357{ 358 int rc, retries; 359 int i; 360 unsigned char value[6]; 361 unsigned char ser_cont; 362 363 ser_cont = (len & 0x07) | 0x10; 364 365 value[0] = addr; 366 value[1] = ser_cont; 367 for (i = 0; i < len; i++) 368 value[i + 2] = buf[i]; 369 370 for (retries = 5;;) { 371 rc = usb_control_msg(usbvision->dev, 372 usb_sndctrlpipe(usbvision->dev, 1), 373 USBVISION_OP_CODE, 374 USB_DIR_OUT | USB_TYPE_VENDOR | 375 USB_RECIP_ENDPOINT, 0, 376 (__u16) USBVISION_SER_ADRS, value, 377 len + 2, HZ); 378 379 if (rc < 0) 380 return rc; 381 382 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 383 (len & 0x07) | 0x10); 384 if (rc < 0) 385 return rc; 386 387 /* Test for Busy and ACK */ 388 do { 389 rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT); 390 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */ 391 if (rc < 0) 392 return rc; 393 394 if ((rc & 0x20) == 0) /* Ack? */ 395 break; 396 397 /* I2C abort */ 398 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00); 399 400 if (--retries < 0) 401 return -1; 402 403 } 404 405 if (i2c_debug & DBG_I2C) { 406 int idx; 407 for (idx = 0; idx < len; idx++) { 408 PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr); 409 } 410 } 411 return len; 412} 413 414static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf, 415 short len) 416{ 417 char *bufPtr = buf; 418 int retval; 419 int wrcount = 0; 420 int count; 421 int maxLen = 4; 422 423 while (len > 0) { 424 count = (len > maxLen) ? maxLen : len; 425 retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count); 426 if (retval > 0) { 427 len -= count; 428 bufPtr += count; 429 wrcount += count; 430 } else 431 return (retval < 0) ? retval : -EFAULT; 432 } 433 return wrcount; 434} 435 436static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf, 437 short len) 438{ 439 char temp[4]; 440 int retval, i; 441 int rdcount = 0; 442 int count; 443 444 while (len > 0) { 445 count = (len > 3) ? 4 : len; 446 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count); 447 if (retval > 0) { 448 for (i = 0; i < len; i++) 449 buf[rdcount + i] = temp[i]; 450 len -= count; 451 rdcount += count; 452 } else 453 return (retval < 0) ? retval : -EFAULT; 454 } 455 return rdcount; 456} 457 458static struct i2c_adapter i2c_adap_template = { 459 .owner = THIS_MODULE, 460 .name = "usbvision", 461}; 462 463/* 464 * Overrides for Emacs so that we follow Linus's tabbing style. 465 * --------------------------------------------------------------------------- 466 * Local variables: 467 * c-basic-offset: 8 468 * End: 469 */ 470