1 /* 2 * 3 * device driver for philips saa7134 based TV cards 4 * i2c interface support 5 * 6 * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs] 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 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 21 */ 22 23 #include <linux/init.h> 24 #include <linux/list.h> 25 #include <linux/module.h> 26 #include <linux/kernel.h> 27 #include <linux/delay.h> 28 29 #include "saa7134-reg.h" 30 #include "saa7134.h" 31 #include <media/v4l2-common.h> 32 33 /* ----------------------------------------------------------- */ 34 35 static unsigned int i2c_debug; 36 module_param(i2c_debug, int, 0644); 37 MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]"); 38 39 static unsigned int i2c_scan; 40 module_param(i2c_scan, int, 0444); 41 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time"); 42 43 #define d1printk if (1 == i2c_debug) printk 44 #define d2printk if (2 == i2c_debug) printk 45 46 #define I2C_WAIT_DELAY 32 47 #define I2C_WAIT_RETRY 16 48 49 /* ----------------------------------------------------------- */ 50 51 static char *str_i2c_status[] = { 52 "IDLE", "DONE_STOP", "BUSY", "TO_SCL", "TO_ARB", "DONE_WRITE", 53 "DONE_READ", "DONE_WRITE_TO", "DONE_READ_TO", "NO_DEVICE", 54 "NO_ACKN", "BUS_ERR", "ARB_LOST", "SEQ_ERR", "ST_ERR", "SW_ERR" 55 }; 56 57 enum i2c_status { 58 IDLE = 0, // no I2C command pending 59 DONE_STOP = 1, // I2C command done and STOP executed 60 BUSY = 2, // executing I2C command 61 TO_SCL = 3, // executing I2C command, time out on clock stretching 62 TO_ARB = 4, // time out on arbitration trial, still trying 63 DONE_WRITE = 5, // I2C command done and awaiting next write command 64 DONE_READ = 6, // I2C command done and awaiting next read command 65 DONE_WRITE_TO = 7, // see 5, and time out on status echo 66 DONE_READ_TO = 8, // see 6, and time out on status echo 67 NO_DEVICE = 9, // no acknowledge on device slave address 68 NO_ACKN = 10, // no acknowledge after data byte transfer 69 BUS_ERR = 11, // bus error 70 ARB_LOST = 12, // arbitration lost during transfer 71 SEQ_ERR = 13, // erroneous programming sequence 72 ST_ERR = 14, // wrong status echoing 73 SW_ERR = 15 // software error 74 }; 75 76 static char *str_i2c_attr[] = { 77 "NOP", "STOP", "CONTINUE", "START" 78 }; 79 80 enum i2c_attr { 81 NOP = 0, // no operation on I2C bus 82 STOP = 1, // stop condition, no associated byte transfer 83 CONTINUE = 2, // continue with byte transfer 84 START = 3 // start condition with byte transfer 85 }; 86 87 static inline enum i2c_status i2c_get_status(struct saa7134_dev *dev) 88 { 89 enum i2c_status status; 90 91 status = saa_readb(SAA7134_I2C_ATTR_STATUS) & 0x0f; 92 d2printk(KERN_DEBUG "%s: i2c stat <= %s\n",dev->name, 93 str_i2c_status[status]); 94 return status; 95 } 96 97 static inline void i2c_set_status(struct saa7134_dev *dev, 98 enum i2c_status status) 99 { 100 d2printk(KERN_DEBUG "%s: i2c stat => %s\n",dev->name, 101 str_i2c_status[status]); 102 saa_andorb(SAA7134_I2C_ATTR_STATUS,0x0f,status); 103 } 104 105 static inline void i2c_set_attr(struct saa7134_dev *dev, enum i2c_attr attr) 106 { 107 d2printk(KERN_DEBUG "%s: i2c attr => %s\n",dev->name, 108 str_i2c_attr[attr]); 109 saa_andorb(SAA7134_I2C_ATTR_STATUS,0xc0,attr << 6); 110 } 111 112 static inline int i2c_is_error(enum i2c_status status) 113 { 114 switch (status) { 115 case NO_DEVICE: 116 case NO_ACKN: 117 case BUS_ERR: 118 case ARB_LOST: 119 case SEQ_ERR: 120 case ST_ERR: 121 return true; 122 default: 123 return false; 124 } 125 } 126 127 static inline int i2c_is_idle(enum i2c_status status) 128 { 129 switch (status) { 130 case IDLE: 131 case DONE_STOP: 132 return true; 133 default: 134 return false; 135 } 136 } 137 138 static inline int i2c_is_busy(enum i2c_status status) 139 { 140 switch (status) { 141 case BUSY: 142 case TO_SCL: 143 case TO_ARB: 144 return true; 145 default: 146 return false; 147 } 148 } 149 150 static int i2c_is_busy_wait(struct saa7134_dev *dev) 151 { 152 enum i2c_status status; 153 int count; 154 155 for (count = 0; count < I2C_WAIT_RETRY; count++) { 156 status = i2c_get_status(dev); 157 if (!i2c_is_busy(status)) 158 break; 159 saa_wait(I2C_WAIT_DELAY); 160 } 161 if (I2C_WAIT_RETRY == count) 162 return false; 163 return true; 164 } 165 166 static int i2c_reset(struct saa7134_dev *dev) 167 { 168 enum i2c_status status; 169 int count; 170 171 d2printk(KERN_DEBUG "%s: i2c reset\n",dev->name); 172 status = i2c_get_status(dev); 173 if (!i2c_is_error(status)) 174 return true; 175 i2c_set_status(dev,status); 176 177 for (count = 0; count < I2C_WAIT_RETRY; count++) { 178 status = i2c_get_status(dev); 179 if (!i2c_is_error(status)) 180 break; 181 udelay(I2C_WAIT_DELAY); 182 } 183 if (I2C_WAIT_RETRY == count) 184 return false; 185 186 if (!i2c_is_idle(status)) 187 return false; 188 189 i2c_set_attr(dev,NOP); 190 return true; 191 } 192 193 static inline int i2c_send_byte(struct saa7134_dev *dev, 194 enum i2c_attr attr, 195 unsigned char data) 196 { 197 enum i2c_status status; 198 __u32 dword; 199 200 /* have to write both attr + data in one 32bit word */ 201 dword = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2); 202 dword &= 0x0f; 203 dword |= (attr << 6); 204 dword |= ((__u32)data << 8); 205 dword |= 0x00 << 16; /* 100 kHz */ 206 // dword |= 0x40 << 16; /* 400 kHz */ 207 dword |= 0xf0 << 24; 208 saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword); 209 d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data); 210 211 if (!i2c_is_busy_wait(dev)) 212 return -EIO; 213 status = i2c_get_status(dev); 214 if (i2c_is_error(status)) 215 return -EIO; 216 return 0; 217 } 218 219 static inline int i2c_recv_byte(struct saa7134_dev *dev) 220 { 221 enum i2c_status status; 222 unsigned char data; 223 224 i2c_set_attr(dev,CONTINUE); 225 if (!i2c_is_busy_wait(dev)) 226 return -EIO; 227 status = i2c_get_status(dev); 228 if (i2c_is_error(status)) 229 return -EIO; 230 data = saa_readb(SAA7134_I2C_DATA); 231 d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data); 232 return data; 233 } 234 235 static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap, 236 struct i2c_msg *msgs, int num) 237 { 238 struct saa7134_dev *dev = i2c_adap->algo_data; 239 enum i2c_status status; 240 unsigned char data; 241 int addr,rc,i,byte; 242 243 status = i2c_get_status(dev); 244 if (!i2c_is_idle(status)) 245 if (!i2c_reset(dev)) 246 return -EIO; 247 248 d2printk("start xfer\n"); 249 d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name); 250 for (i = 0; i < num; i++) { 251 if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) { 252 /* send address */ 253 d2printk("send address\n"); 254 addr = msgs[i].addr << 1; 255 if (msgs[i].flags & I2C_M_RD) 256 addr |= 1; 257 if (i > 0 && msgs[i].flags & 258 I2C_M_RD && msgs[i].addr != 0x40 && 259 msgs[i].addr != 0x19) { 260 /* workaround for a saa7134 i2c bug 261 * needed to talk to the mt352 demux 262 * thanks to pinnacle for the hint */ 263 int quirk = 0xfe; 264 d1printk(" [%02x quirk]",quirk); 265 i2c_send_byte(dev,START,quirk); 266 i2c_recv_byte(dev); 267 } 268 d1printk(" < %02x", addr); 269 rc = i2c_send_byte(dev,START,addr); 270 if (rc < 0) 271 goto err; 272 } 273 if (msgs[i].flags & I2C_M_RD) { 274 /* read bytes */ 275 d2printk("read bytes\n"); 276 for (byte = 0; byte < msgs[i].len; byte++) { 277 d1printk(" ="); 278 rc = i2c_recv_byte(dev); 279 if (rc < 0) 280 goto err; 281 d1printk("%02x", rc); 282 msgs[i].buf[byte] = rc; 283 } 284 /* discard mysterious extra byte when reading 285 from Samsung S5H1411. i2c bus gets error 286 if we do not. */ 287 if (0x19 == msgs[i].addr) { 288 d1printk(" ?"); 289 rc = i2c_recv_byte(dev); 290 if (rc < 0) 291 goto err; 292 d1printk("%02x", rc); 293 } 294 } else { 295 /* write bytes */ 296 d2printk("write bytes\n"); 297 for (byte = 0; byte < msgs[i].len; byte++) { 298 data = msgs[i].buf[byte]; 299 d1printk(" %02x", data); 300 rc = i2c_send_byte(dev,CONTINUE,data); 301 if (rc < 0) 302 goto err; 303 } 304 } 305 } 306 d2printk("xfer done\n"); 307 d1printk(" >"); 308 i2c_set_attr(dev,STOP); 309 rc = -EIO; 310 if (!i2c_is_busy_wait(dev)) 311 goto err; 312 status = i2c_get_status(dev); 313 if (i2c_is_error(status)) 314 goto err; 315 /* ensure that the bus is idle for at least one bit slot */ 316 msleep(1); 317 318 d1printk("\n"); 319 return num; 320 err: 321 if (1 == i2c_debug) { 322 status = i2c_get_status(dev); 323 printk(" ERROR: %s\n",str_i2c_status[status]); 324 } 325 return rc; 326 } 327 328 /* ----------------------------------------------------------- */ 329 330 static u32 functionality(struct i2c_adapter *adap) 331 { 332 return I2C_FUNC_SMBUS_EMUL; 333 } 334 335 static struct i2c_algorithm saa7134_algo = { 336 .master_xfer = saa7134_i2c_xfer, 337 .functionality = functionality, 338 }; 339 340 static struct i2c_adapter saa7134_adap_template = { 341 .owner = THIS_MODULE, 342 .name = "saa7134", 343 .algo = &saa7134_algo, 344 }; 345 346 static struct i2c_client saa7134_client_template = { 347 .name = "saa7134 internal", 348 }; 349 350 /* ----------------------------------------------------------- */ 351 352 static int 353 saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len) 354 { 355 unsigned char buf; 356 int i,err; 357 358 dev->i2c_client.addr = 0xa0 >> 1; 359 buf = 0; 360 if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) { 361 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n", 362 dev->name,err); 363 return -1; 364 } 365 if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) { 366 printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n", 367 dev->name,err); 368 return -1; 369 } 370 for (i = 0; i < len; i++) { 371 if (0 == (i % 16)) 372 printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i); 373 printk(" %02x",eedata[i]); 374 if (15 == (i % 16)) 375 printk("\n"); 376 } 377 return 0; 378 } 379 380 static char *i2c_devs[128] = { 381 [ 0x20 ] = "mpeg encoder (saa6752hs)", 382 [ 0xa0 >> 1 ] = "eeprom", 383 [ 0xc0 >> 1 ] = "tuner (analog)", 384 [ 0x86 >> 1 ] = "tda9887", 385 [ 0x5a >> 1 ] = "remote control", 386 }; 387 388 static void do_i2c_scan(char *name, struct i2c_client *c) 389 { 390 unsigned char buf; 391 int i,rc; 392 393 for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) { 394 c->addr = i; 395 rc = i2c_master_recv(c,&buf,0); 396 if (rc < 0) 397 continue; 398 printk("%s: i2c scan: found device @ 0x%x [%s]\n", 399 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???"); 400 } 401 } 402 403 int saa7134_i2c_register(struct saa7134_dev *dev) 404 { 405 dev->i2c_adap = saa7134_adap_template; 406 dev->i2c_adap.dev.parent = &dev->pci->dev; 407 strcpy(dev->i2c_adap.name,dev->name); 408 dev->i2c_adap.algo_data = dev; 409 i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev); 410 i2c_add_adapter(&dev->i2c_adap); 411 412 dev->i2c_client = saa7134_client_template; 413 dev->i2c_client.adapter = &dev->i2c_adap; 414 415 saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata)); 416 if (i2c_scan) 417 do_i2c_scan(dev->name,&dev->i2c_client); 418 419 /* Instantiate the IR receiver device, if present */ 420 saa7134_probe_i2c_ir(dev); 421 return 0; 422 } 423 424 int saa7134_i2c_unregister(struct saa7134_dev *dev) 425 { 426 i2c_del_adapter(&dev->i2c_adap); 427 return 0; 428 } 429 430 /* ----------------------------------------------------------- */ 431 /* 432 * Local variables: 433 * c-basic-offset: 8 434 * End: 435 */ 436