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 35static unsigned int i2c_debug; 36module_param(i2c_debug, int, 0644); 37MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]"); 38 39static unsigned int i2c_scan; 40module_param(i2c_scan, int, 0444); 41MODULE_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 51static 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 57enum 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 76static char *str_i2c_attr[] = { 77 "NOP", "STOP", "CONTINUE", "START" 78}; 79 80enum 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 87static 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 97static 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 105static 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 112static 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 127static 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 138static 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 150static 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 166static 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 193static 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 219static 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 235static 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 & I2C_M_RD && msgs[i].addr != 0x40) { 258 /* workaround for a saa7134 i2c bug 259 * needed to talk to the mt352 demux 260 * thanks to pinnacle for the hint */ 261 int quirk = 0xfe; 262 d1printk(" [%02x quirk]",quirk); 263 i2c_send_byte(dev,START,quirk); 264 i2c_recv_byte(dev); 265 } 266 d1printk(" < %02x", addr); 267 rc = i2c_send_byte(dev,START,addr); 268 if (rc < 0) 269 goto err; 270 } 271 if (msgs[i].flags & I2C_M_RD) { 272 /* read bytes */ 273 d2printk("read bytes\n"); 274 for (byte = 0; byte < msgs[i].len; byte++) { 275 d1printk(" ="); 276 rc = i2c_recv_byte(dev); 277 if (rc < 0) 278 goto err; 279 d1printk("%02x", rc); 280 msgs[i].buf[byte] = rc; 281 } 282 } else { 283 /* write bytes */ 284 d2printk("write bytes\n"); 285 for (byte = 0; byte < msgs[i].len; byte++) { 286 data = msgs[i].buf[byte]; 287 d1printk(" %02x", data); 288 rc = i2c_send_byte(dev,CONTINUE,data); 289 if (rc < 0) 290 goto err; 291 } 292 } 293 } 294 d2printk("xfer done\n"); 295 d1printk(" >"); 296 i2c_set_attr(dev,STOP); 297 rc = -EIO; 298 if (!i2c_is_busy_wait(dev)) 299 goto err; 300 status = i2c_get_status(dev); 301 if (i2c_is_error(status)) 302 goto err; 303 /* ensure that the bus is idle for at least one bit slot */ 304 msleep(1); 305 306 d1printk("\n"); 307 return num; 308 err: 309 if (1 == i2c_debug) { 310 status = i2c_get_status(dev); 311 printk(" ERROR: %s\n",str_i2c_status[status]); 312 } 313 return rc; 314} 315 316/* ----------------------------------------------------------- */ 317 318static u32 functionality(struct i2c_adapter *adap) 319{ 320 return I2C_FUNC_SMBUS_EMUL; 321} 322 323static struct i2c_algorithm saa7134_algo = { 324 .master_xfer = saa7134_i2c_xfer, 325 .functionality = functionality, 326}; 327 328static struct i2c_adapter saa7134_adap_template = { 329 .owner = THIS_MODULE, 330 .name = "saa7134", 331 .algo = &saa7134_algo, 332}; 333 334static struct i2c_client saa7134_client_template = { 335 .name = "saa7134 internal", 336}; 337 338/* ----------------------------------------------------------- */ 339 340static int 341saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len) 342{ 343 unsigned char buf; 344 int i,err; 345 346 dev->i2c_client.addr = 0xa0 >> 1; 347 buf = 0; 348 if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) { 349 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n", 350 dev->name,err); 351 return -1; 352 } 353 if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) { 354 printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n", 355 dev->name,err); 356 return -1; 357 } 358 for (i = 0; i < len; i++) { 359 if (0 == (i % 16)) 360 printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i); 361 printk(" %02x",eedata[i]); 362 if (15 == (i % 16)) 363 printk("\n"); 364 } 365 return 0; 366} 367 368static char *i2c_devs[128] = { 369 [ 0x20 ] = "mpeg encoder (saa6752hs)", 370 [ 0xa0 >> 1 ] = "eeprom", 371 [ 0xc0 >> 1 ] = "tuner (analog)", 372 [ 0x86 >> 1 ] = "tda9887", 373 [ 0x5a >> 1 ] = "remote control", 374}; 375 376static void do_i2c_scan(char *name, struct i2c_client *c) 377{ 378 unsigned char buf; 379 int i,rc; 380 381 for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) { 382 c->addr = i; 383 rc = i2c_master_recv(c,&buf,0); 384 if (rc < 0) 385 continue; 386 printk("%s: i2c scan: found device @ 0x%x [%s]\n", 387 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???"); 388 } 389} 390 391int saa7134_i2c_register(struct saa7134_dev *dev) 392{ 393 dev->i2c_adap = saa7134_adap_template; 394 dev->i2c_adap.dev.parent = &dev->pci->dev; 395 strcpy(dev->i2c_adap.name,dev->name); 396 dev->i2c_adap.algo_data = dev; 397 i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev); 398 i2c_add_adapter(&dev->i2c_adap); 399 400 dev->i2c_client = saa7134_client_template; 401 dev->i2c_client.adapter = &dev->i2c_adap; 402 403 saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata)); 404 if (i2c_scan) 405 do_i2c_scan(dev->name,&dev->i2c_client); 406 407 /* Instantiate the IR receiver device, if present */ 408 saa7134_probe_i2c_ir(dev); 409 return 0; 410} 411 412int saa7134_i2c_unregister(struct saa7134_dev *dev) 413{ 414 i2c_del_adapter(&dev->i2c_adap); 415 return 0; 416} 417 418/* ----------------------------------------------------------- */ 419/* 420 * Local variables: 421 * c-basic-offset: 8 422 * End: 423 */ 424