1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 4 bttv-i2c.c -- all the i2c code is here 5 6 bttv - Bt848 frame grabber driver 7 8 Copyright (C) 1996,97,98 Ralph Metzler (rjkm@thp.uni-koeln.de) 9 & Marcus Metzler (mocm@thp.uni-koeln.de) 10 (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org> 11 12 (c) 2005 Mauro Carvalho Chehab <mchehab@kernel.org> 13 - Multituner support and i2c address binding 14 15 16 */ 17 18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 19 20 #include <linux/module.h> 21 #include <linux/init.h> 22 #include <linux/delay.h> 23 24 #include "bttvp.h" 25 #include <media/v4l2-common.h> 26 #include <linux/jiffies.h> 27 #include <asm/io.h> 28 29 static int i2c_debug; 30 static int i2c_hw; 31 static int i2c_scan; 32 module_param(i2c_debug, int, 0644); 33 MODULE_PARM_DESC(i2c_debug, "configure i2c debug level"); 34 module_param(i2c_hw, int, 0444); 35 MODULE_PARM_DESC(i2c_hw, "force use of hardware i2c support, instead of software bitbang"); 36 module_param(i2c_scan, int, 0444); 37 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time"); 38 39 static unsigned int i2c_udelay = 5; 40 module_param(i2c_udelay, int, 0444); 41 MODULE_PARM_DESC(i2c_udelay, "soft i2c delay at insmod time, in usecs (should be 5 or higher). Lower value means higher bus speed."); 42 43 /* ----------------------------------------------------------------------- */ 44 /* I2C functions - bitbanging adapter (software i2c) */ 45 bttv_bit_setscl(void * data,int state)46 static void bttv_bit_setscl(void *data, int state) 47 { 48 struct bttv *btv = (struct bttv*)data; 49 50 if (state) 51 btv->i2c_state |= 0x02; 52 else 53 btv->i2c_state &= ~0x02; 54 btwrite(btv->i2c_state, BT848_I2C); 55 btread(BT848_I2C); 56 } 57 bttv_bit_setsda(void * data,int state)58 static void bttv_bit_setsda(void *data, int state) 59 { 60 struct bttv *btv = (struct bttv*)data; 61 62 if (state) 63 btv->i2c_state |= 0x01; 64 else 65 btv->i2c_state &= ~0x01; 66 btwrite(btv->i2c_state, BT848_I2C); 67 btread(BT848_I2C); 68 } 69 bttv_bit_getscl(void * data)70 static int bttv_bit_getscl(void *data) 71 { 72 struct bttv *btv = (struct bttv*)data; 73 int state; 74 75 state = btread(BT848_I2C) & 0x02 ? 1 : 0; 76 return state; 77 } 78 bttv_bit_getsda(void * data)79 static int bttv_bit_getsda(void *data) 80 { 81 struct bttv *btv = (struct bttv*)data; 82 int state; 83 84 state = btread(BT848_I2C) & 0x01; 85 return state; 86 } 87 88 static const struct i2c_algo_bit_data bttv_i2c_algo_bit_template = { 89 .setsda = bttv_bit_setsda, 90 .setscl = bttv_bit_setscl, 91 .getsda = bttv_bit_getsda, 92 .getscl = bttv_bit_getscl, 93 .udelay = 16, 94 .timeout = 200, 95 }; 96 97 /* ----------------------------------------------------------------------- */ 98 /* I2C functions - hardware i2c */ 99 functionality(struct i2c_adapter * adap)100 static u32 functionality(struct i2c_adapter *adap) 101 { 102 return I2C_FUNC_SMBUS_EMUL; 103 } 104 105 static int bttv_i2c_wait_done(struct bttv * btv)106 bttv_i2c_wait_done(struct bttv *btv) 107 { 108 int rc = 0; 109 110 /* timeout */ 111 if (wait_event_interruptible_timeout(btv->i2c_queue, 112 btv->i2c_done, msecs_to_jiffies(85)) == -ERESTARTSYS) 113 rc = -EIO; 114 115 if (btv->i2c_done & BT848_INT_RACK) 116 rc = 1; 117 btv->i2c_done = 0; 118 return rc; 119 } 120 121 #define I2C_HW (BT878_I2C_MODE | BT848_I2C_SYNC |\ 122 BT848_I2C_SCL | BT848_I2C_SDA) 123 124 static int bttv_i2c_sendbytes(struct bttv * btv,const struct i2c_msg * msg,int last)125 bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last) 126 { 127 u32 xmit; 128 int retval,cnt; 129 130 /* sanity checks */ 131 if (0 == msg->len) 132 return -EINVAL; 133 134 /* start, address + first byte */ 135 xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW; 136 if (msg->len > 1 || !last) 137 xmit |= BT878_I2C_NOSTOP; 138 btwrite(xmit, BT848_I2C); 139 retval = bttv_i2c_wait_done(btv); 140 if (retval < 0) 141 goto err; 142 if (retval == 0) 143 goto eio; 144 if (i2c_debug) { 145 pr_cont(" <W %02x %02x", msg->addr << 1, msg->buf[0]); 146 } 147 148 for (cnt = 1; cnt < msg->len; cnt++ ) { 149 /* following bytes */ 150 xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART; 151 if (cnt < msg->len-1 || !last) 152 xmit |= BT878_I2C_NOSTOP; 153 btwrite(xmit, BT848_I2C); 154 retval = bttv_i2c_wait_done(btv); 155 if (retval < 0) 156 goto err; 157 if (retval == 0) 158 goto eio; 159 if (i2c_debug) 160 pr_cont(" %02x", msg->buf[cnt]); 161 } 162 if (i2c_debug && !(xmit & BT878_I2C_NOSTOP)) 163 pr_cont(">\n"); 164 return msg->len; 165 166 eio: 167 retval = -EIO; 168 err: 169 if (i2c_debug) 170 pr_cont(" ERR: %d\n",retval); 171 return retval; 172 } 173 174 static int bttv_i2c_readbytes(struct bttv * btv,const struct i2c_msg * msg,int last)175 bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last) 176 { 177 u32 xmit; 178 u32 cnt; 179 int retval; 180 181 for (cnt = 0; cnt < msg->len; cnt++) { 182 xmit = (msg->addr << 25) | (1 << 24) | I2C_HW; 183 if (cnt < msg->len-1) 184 xmit |= BT848_I2C_W3B; 185 if (cnt < msg->len-1 || !last) 186 xmit |= BT878_I2C_NOSTOP; 187 if (cnt) 188 xmit |= BT878_I2C_NOSTART; 189 190 if (i2c_debug) { 191 if (!(xmit & BT878_I2C_NOSTART)) 192 pr_cont(" <R %02x", (msg->addr << 1) +1); 193 } 194 195 btwrite(xmit, BT848_I2C); 196 retval = bttv_i2c_wait_done(btv); 197 if (retval < 0) 198 goto err; 199 if (retval == 0) 200 goto eio; 201 msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff; 202 if (i2c_debug) { 203 pr_cont(" =%02x", msg->buf[cnt]); 204 } 205 if (i2c_debug && !(xmit & BT878_I2C_NOSTOP)) 206 pr_cont(" >\n"); 207 } 208 209 210 return msg->len; 211 212 eio: 213 retval = -EIO; 214 err: 215 if (i2c_debug) 216 pr_cont(" ERR: %d\n",retval); 217 return retval; 218 } 219 bttv_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)220 static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num) 221 { 222 struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap); 223 struct bttv *btv = to_bttv(v4l2_dev); 224 int retval = 0; 225 int i; 226 227 if (i2c_debug) 228 pr_debug("bt-i2c:"); 229 230 btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT); 231 for (i = 0 ; i < num; i++) { 232 if (msgs[i].flags & I2C_M_RD) { 233 /* read */ 234 retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num); 235 if (retval < 0) 236 goto err; 237 } else { 238 /* write */ 239 retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num); 240 if (retval < 0) 241 goto err; 242 } 243 } 244 return num; 245 246 err: 247 return retval; 248 } 249 250 static const struct i2c_algorithm bttv_algo = { 251 .master_xfer = bttv_i2c_xfer, 252 .functionality = functionality, 253 }; 254 255 /* ----------------------------------------------------------------------- */ 256 /* I2C functions - common stuff */ 257 258 /* read I2C */ bttv_I2CRead(struct bttv * btv,unsigned char addr,char * probe_for)259 int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for) 260 { 261 unsigned char buffer = 0; 262 263 if (0 != btv->i2c_rc) 264 return -1; 265 if (bttv_verbose && NULL != probe_for) 266 pr_info("%d: i2c: checking for %s @ 0x%02x... ", 267 btv->c.nr, probe_for, addr); 268 btv->i2c_client.addr = addr >> 1; 269 if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) { 270 if (NULL != probe_for) { 271 if (bttv_verbose) 272 pr_cont("not found\n"); 273 } else 274 pr_warn("%d: i2c read 0x%x: error\n", 275 btv->c.nr, addr); 276 return -1; 277 } 278 if (bttv_verbose && NULL != probe_for) 279 pr_cont("found\n"); 280 return buffer; 281 } 282 283 /* write I2C */ bttv_I2CWrite(struct bttv * btv,unsigned char addr,unsigned char b1,unsigned char b2,int both)284 int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1, 285 unsigned char b2, int both) 286 { 287 unsigned char buffer[2]; 288 int bytes = both ? 2 : 1; 289 290 if (0 != btv->i2c_rc) 291 return -1; 292 btv->i2c_client.addr = addr >> 1; 293 buffer[0] = b1; 294 buffer[1] = b2; 295 if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes)) 296 return -1; 297 return 0; 298 } 299 300 /* read EEPROM content */ bttv_readee(struct bttv * btv,unsigned char * eedata,int addr)301 void bttv_readee(struct bttv *btv, unsigned char *eedata, int addr) 302 { 303 memset(eedata, 0, 256); 304 if (0 != btv->i2c_rc) 305 return; 306 btv->i2c_client.addr = addr >> 1; 307 tveeprom_read(&btv->i2c_client, eedata, 256); 308 } 309 310 static char *i2c_devs[128] = { 311 [ 0x1c >> 1 ] = "lgdt330x", 312 [ 0x30 >> 1 ] = "IR (hauppauge)", 313 [ 0x80 >> 1 ] = "msp34xx", 314 [ 0x86 >> 1 ] = "tda9887", 315 [ 0xa0 >> 1 ] = "eeprom", 316 [ 0xc0 >> 1 ] = "tuner (analog)", 317 [ 0xc2 >> 1 ] = "tuner (analog)", 318 }; 319 do_i2c_scan(char * name,struct i2c_client * c)320 static void do_i2c_scan(char *name, struct i2c_client *c) 321 { 322 unsigned char buf; 323 int i,rc; 324 325 for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) { 326 c->addr = i; 327 rc = i2c_master_recv(c,&buf,0); 328 if (rc < 0) 329 continue; 330 pr_info("%s: i2c scan: found device @ 0x%x [%s]\n", 331 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???"); 332 } 333 } 334 335 /* init + register i2c adapter */ init_bttv_i2c(struct bttv * btv)336 int init_bttv_i2c(struct bttv *btv) 337 { 338 strscpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE); 339 340 if (i2c_hw) 341 btv->use_i2c_hw = 1; 342 if (btv->use_i2c_hw) { 343 /* bt878 */ 344 strscpy(btv->c.i2c_adap.name, "bt878", 345 sizeof(btv->c.i2c_adap.name)); 346 btv->c.i2c_adap.algo = &bttv_algo; 347 } else { 348 /* bt848 */ 349 /* Prevents usage of invalid delay values */ 350 if (i2c_udelay<5) 351 i2c_udelay=5; 352 353 strscpy(btv->c.i2c_adap.name, "bttv", 354 sizeof(btv->c.i2c_adap.name)); 355 btv->i2c_algo = bttv_i2c_algo_bit_template; 356 btv->i2c_algo.udelay = i2c_udelay; 357 btv->i2c_algo.data = btv; 358 btv->c.i2c_adap.algo_data = &btv->i2c_algo; 359 } 360 btv->c.i2c_adap.owner = THIS_MODULE; 361 362 btv->c.i2c_adap.dev.parent = &btv->c.pci->dev; 363 snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name), 364 "bt%d #%d [%s]", btv->id, btv->c.nr, 365 btv->use_i2c_hw ? "hw" : "sw"); 366 367 i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev); 368 btv->i2c_client.adapter = &btv->c.i2c_adap; 369 370 371 if (btv->use_i2c_hw) { 372 btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap); 373 } else { 374 bttv_bit_setscl(btv,1); 375 bttv_bit_setsda(btv,1); 376 btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap); 377 } 378 if (0 == btv->i2c_rc && i2c_scan) 379 do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client); 380 381 return btv->i2c_rc; 382 } 383 fini_bttv_i2c(struct bttv * btv)384 int fini_bttv_i2c(struct bttv *btv) 385 { 386 if (btv->i2c_rc == 0) 387 i2c_del_adapter(&btv->c.i2c_adap); 388 389 return 0; 390 } 391
