drivers/media/dvb-frontends/dibx000_common.c

   1 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   2
   3 #include <linux/i2c.h>
   4 #include <linux/mutex.h>
   5 #include <linux/module.h>
   6
   7 #include "dibx000_common.h"
   8
   9 static int debug;
  10 module_param(debug, int, 0644);
  11 MODULE_PARM_DESC(debug, "turn on debugging (default: 0)");
  12
  13 #define dprintk(fmt, arg...) do {                                       \
  14         if (debug)                                                      \
  15                 printk(KERN_DEBUG pr_fmt("%s: " fmt),                   \
  16                        __func__, ##arg);                                \
  17 } while (0)
  18
  19 static int dibx000_write_word(struct dibx000_i2c_master *mst, u16 reg, u16 val)
  20 {
  21         int ret;
  22
  23         if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
  24                 dprintk("could not acquire lock\n");
  25                 return -EINVAL;
  26         }
  27
  28         mst->i2c_write_buffer[0] = (reg >> 8) & 0xff;
  29         mst->i2c_write_buffer[1] = reg & 0xff;
  30         mst->i2c_write_buffer[2] = (val >> 8) & 0xff;
  31         mst->i2c_write_buffer[3] = val & 0xff;
  32
  33         memset(mst->msg, 0, sizeof(struct i2c_msg));
  34         mst->msg[0].addr = mst->i2c_addr;
  35         mst->msg[0].flags = 0;
  36         mst->msg[0].buf = mst->i2c_write_buffer;
  37         mst->msg[0].len = 4;
  38
  39         ret = i2c_transfer(mst->i2c_adap, mst->msg, 1) != 1 ? -EREMOTEIO : 0;
  40         mutex_unlock(&mst->i2c_buffer_lock);
  41
  42         return ret;
  43 }
  44
  45 static u16 dibx000_read_word(struct dibx000_i2c_master *mst, u16 reg)
  46 {
  47         u16 ret;
  48
  49         if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
  50                 dprintk("could not acquire lock\n");
  51                 return 0;
  52         }
  53
  54         mst->i2c_write_buffer[0] = reg >> 8;
  55         mst->i2c_write_buffer[1] = reg & 0xff;
  56
  57         memset(mst->msg, 0, 2 * sizeof(struct i2c_msg));
  58         mst->msg[0].addr = mst->i2c_addr;
  59         mst->msg[0].flags = 0;
  60         mst->msg[0].buf = mst->i2c_write_buffer;
  61         mst->msg[0].len = 2;
  62         mst->msg[1].addr = mst->i2c_addr;
  63         mst->msg[1].flags = I2C_M_RD;
  64         mst->msg[1].buf = mst->i2c_read_buffer;
  65         mst->msg[1].len = 2;
  66
  67         if (i2c_transfer(mst->i2c_adap, mst->msg, 2) != 2)
  68                 dprintk("i2c read error on %d\n", reg);
  69
  70         ret = (mst->i2c_read_buffer[0] << 8) | mst->i2c_read_buffer[1];
  71         mutex_unlock(&mst->i2c_buffer_lock);
  72
  73         return ret;
  74 }
  75
  76 static int dibx000_is_i2c_done(struct dibx000_i2c_master *mst)
  77 {
  78         int i = 100;
  79         u16 status;
  80
  81         while (((status = dibx000_read_word(mst, mst->base_reg + 2)) & 0x0100) == 0 && --i > 0)
  82                 ;
  83
  84         /* i2c timed out */
  85         if (i == 0)
  86                 return -EREMOTEIO;
  87
  88         /* no acknowledge */
  89         if ((status & 0x0080) == 0)
  90                 return -EREMOTEIO;
  91
  92         return 0;
  93 }
  94
  95 static int dibx000_master_i2c_write(struct dibx000_i2c_master *mst, struct i2c_msg *msg, u8 stop)
  96 {
  97         u16 data;
  98         u16 da;
  99         u16 i;
 100         u16 txlen = msg->len, len;
 101         const u8 *b = msg->buf;
 102
 103         while (txlen) {
 104                 dibx000_read_word(mst, mst->base_reg + 2);
 105
 106                 len = txlen > 8 ? 8 : txlen;
 107                 for (i = 0; i < len; i += 2) {
 108                         data = *b++ << 8;
 109                         if (i+1 < len)
 110                                 data |= *b++;
 111                         dibx000_write_word(mst, mst->base_reg, data);
 112                 }
 113                 da = (((u8) (msg->addr))  << 9) |
 114                         (1           << 8) |
 115                         (1           << 7) |
 116                         (0           << 6) |
 117                         (0           << 5) |
 118                         ((len & 0x7) << 2) |
 119                         (0           << 1) |
 120                         (0           << 0);
 121
 122                 if (txlen == msg->len)
 123                         da |= 1 << 5; /* start */
 124
 125                 if (txlen-len == 0 && stop)
 126                         da |= 1 << 6; /* stop */
 127
 128                 dibx000_write_word(mst, mst->base_reg+1, da);
 129
 130                 if (dibx000_is_i2c_done(mst) != 0)
 131                         return -EREMOTEIO;
 132                 txlen -= len;
 133         }
 134
 135         return 0;
 136 }
 137
 138 static int dibx000_master_i2c_read(struct dibx000_i2c_master *mst, struct i2c_msg *msg)
 139 {
 140         u16 da;
 141         u8 *b = msg->buf;
 142         u16 rxlen = msg->len, len;
 143
 144         while (rxlen) {
 145                 len = rxlen > 8 ? 8 : rxlen;
 146                 da = (((u8) (msg->addr)) << 9) |
 147                         (1           << 8) |
 148                         (1           << 7) |
 149                         (0           << 6) |
 150                         (0           << 5) |
 151                         ((len & 0x7) << 2) |
 152                         (1           << 1) |
 153                         (0           << 0);
 154
 155                 if (rxlen == msg->len)
 156                         da |= 1 << 5; /* start */
 157
 158                 if (rxlen-len == 0)
 159                         da |= 1 << 6; /* stop */
 160                 dibx000_write_word(mst, mst->base_reg+1, da);
 161
 162                 if (dibx000_is_i2c_done(mst) != 0)
 163                         return -EREMOTEIO;
 164
 165                 rxlen -= len;
 166
 167                 while (len) {
 168                         da = dibx000_read_word(mst, mst->base_reg);
 169                         *b++ = (da >> 8) & 0xff;
 170                         len--;
 171                         if (len >= 1) {
 172                                 *b++ =  da   & 0xff;
 173                                 len--;
 174                         }
 175                 }
 176         }
 177
 178         return 0;
 179 }
 180
 181 int dibx000_i2c_set_speed(struct i2c_adapter *i2c_adap, u16 speed)
 182 {
 183         struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 184
 185         if (mst->device_rev < DIB7000MC && speed < 235)
 186                 speed = 235;
 187         return dibx000_write_word(mst, mst->base_reg + 3, (u16)(60000 / speed));
 188
 189 }
 190 EXPORT_SYMBOL(dibx000_i2c_set_speed);
 191
 192 static u32 dibx000_i2c_func(struct i2c_adapter *adapter)
 193 {
 194         return I2C_FUNC_I2C;
 195 }
 196
 197 static int dibx000_i2c_select_interface(struct dibx000_i2c_master *mst,
 198                                         enum dibx000_i2c_interface intf)
 199 {
 200         if (mst->device_rev > DIB3000MC && mst->selected_interface != intf) {
 201                 dprintk("selecting interface: %d\n", intf);
 202                 mst->selected_interface = intf;
 203                 return dibx000_write_word(mst, mst->base_reg + 4, intf);
 204         }
 205         return 0;
 206 }
 207
 208 static int dibx000_i2c_master_xfer_gpio12(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
 209 {
 210         struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 211         int msg_index;
 212         int ret = 0;
 213
 214         dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_1_2);
 215         for (msg_index = 0; msg_index < num; msg_index++) {
 216                 if (msg[msg_index].flags & I2C_M_RD) {
 217                         ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
 218                         if (ret != 0)
 219                                 return 0;
 220                 } else {
 221                         ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
 222                         if (ret != 0)
 223                                 return 0;
 224                 }
 225         }
 226
 227         return num;
 228 }
 229
 230 static int dibx000_i2c_master_xfer_gpio34(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
 231 {
 232         struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 233         int msg_index;
 234         int ret = 0;
 235
 236         dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_3_4);
 237         for (msg_index = 0; msg_index < num; msg_index++) {
 238                 if (msg[msg_index].flags & I2C_M_RD) {
 239                         ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
 240                         if (ret != 0)
 241                                 return 0;
 242                 } else {
 243                         ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
 244                         if (ret != 0)
 245                                 return 0;
 246                 }
 247         }
 248
 249         return num;
 250 }
 251
 252 static struct i2c_algorithm dibx000_i2c_master_gpio12_xfer_algo = {
 253         .master_xfer = dibx000_i2c_master_xfer_gpio12,
 254         .functionality = dibx000_i2c_func,
 255 };
 256
 257 static struct i2c_algorithm dibx000_i2c_master_gpio34_xfer_algo = {
 258         .master_xfer = dibx000_i2c_master_xfer_gpio34,
 259         .functionality = dibx000_i2c_func,
 260 };
 261
 262 static int dibx000_i2c_gate_ctrl(struct dibx000_i2c_master *mst, u8 tx[4],
 263                                  u8 addr, int onoff)
 264 {
 265         u16 val;
 266
 267
 268         if (onoff)
 269                 val = addr << 8;        // bit 7 = use master or not, if 0, the gate is open
 270         else
 271                 val = 1 << 7;
 272
 273         if (mst->device_rev > DIB7000)
 274                 val <<= 1;
 275
 276         tx[0] = (((mst->base_reg + 1) >> 8) & 0xff);
 277         tx[1] = ((mst->base_reg + 1) & 0xff);
 278         tx[2] = val >> 8;
 279         tx[3] = val & 0xff;
 280
 281         return 0;
 282 }
 283
 284 static int dibx000_i2c_gated_gpio67_xfer(struct i2c_adapter *i2c_adap,
 285                                         struct i2c_msg msg[], int num)
 286 {
 287         struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 288         int ret;
 289
 290         if (num > 32) {
 291                 dprintk("%s: too much I2C message to be transmitted (%i). Maximum is 32",
 292                         __func__, num);
 293                 return -ENOMEM;
 294         }
 295
 296         dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_6_7);
 297
 298         if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 299                 dprintk("could not acquire lock\n");
 300                 return -EINVAL;
 301         }
 302
 303         memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
 304
 305         /* open the gate */
 306         dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
 307         mst->msg[0].addr = mst->i2c_addr;
 308         mst->msg[0].buf = &mst->i2c_write_buffer[0];
 309         mst->msg[0].len = 4;
 310
 311         memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
 312
 313         /* close the gate */
 314         dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
 315         mst->msg[num + 1].addr = mst->i2c_addr;
 316         mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
 317         mst->msg[num + 1].len = 4;
 318
 319         ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
 320                         num : -EIO);
 321
 322         mutex_unlock(&mst->i2c_buffer_lock);
 323         return ret;
 324 }
 325
 326 static struct i2c_algorithm dibx000_i2c_gated_gpio67_algo = {
 327         .master_xfer = dibx000_i2c_gated_gpio67_xfer,
 328         .functionality = dibx000_i2c_func,
 329 };
 330
 331 static int dibx000_i2c_gated_tuner_xfer(struct i2c_adapter *i2c_adap,
 332                                         struct i2c_msg msg[], int num)
 333 {
 334         struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 335         int ret;
 336
 337         if (num > 32) {
 338                 dprintk("%s: too much I2C message to be transmitted (%i). Maximum is 32",
 339                         __func__, num);
 340                 return -ENOMEM;
 341         }
 342
 343         dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
 344
 345         if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 346                 dprintk("could not acquire lock\n");
 347                 return -EINVAL;
 348         }
 349         memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
 350
 351         /* open the gate */
 352         dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
 353         mst->msg[0].addr = mst->i2c_addr;
 354         mst->msg[0].buf = &mst->i2c_write_buffer[0];
 355         mst->msg[0].len = 4;
 356
 357         memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
 358
 359         /* close the gate */
 360         dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
 361         mst->msg[num + 1].addr = mst->i2c_addr;
 362         mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
 363         mst->msg[num + 1].len = 4;
 364
 365         ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
 366                         num : -EIO);
 367         mutex_unlock(&mst->i2c_buffer_lock);
 368         return ret;
 369 }
 370
 371 static struct i2c_algorithm dibx000_i2c_gated_tuner_algo = {
 372         .master_xfer = dibx000_i2c_gated_tuner_xfer,
 373         .functionality = dibx000_i2c_func,
 374 };
 375
 376 struct i2c_adapter *dibx000_get_i2c_adapter(struct dibx000_i2c_master *mst,
 377                                                 enum dibx000_i2c_interface intf,
 378                                                 int gating)
 379 {
 380         struct i2c_adapter *i2c = NULL;
 381
 382         switch (intf) {
 383         case DIBX000_I2C_INTERFACE_TUNER:
 384                 if (gating)
 385                         i2c = &mst->gated_tuner_i2c_adap;
 386                 break;
 387         case DIBX000_I2C_INTERFACE_GPIO_1_2:
 388                 if (!gating)
 389                         i2c = &mst->master_i2c_adap_gpio12;
 390                 break;
 391         case DIBX000_I2C_INTERFACE_GPIO_3_4:
 392                 if (!gating)
 393                         i2c = &mst->master_i2c_adap_gpio34;
 394                 break;
 395         case DIBX000_I2C_INTERFACE_GPIO_6_7:
 396                 if (gating)
 397                         i2c = &mst->master_i2c_adap_gpio67;
 398                 break;
 399         default:
 400                 pr_err("incorrect I2C interface selected\n");
 401                 break;
 402         }
 403
 404         return i2c;
 405 }
 406
 407 EXPORT_SYMBOL(dibx000_get_i2c_adapter);
 408
 409 void dibx000_reset_i2c_master(struct dibx000_i2c_master *mst)
 410 {
 411         /* initialize the i2c-master by closing the gate */
 412         u8 tx[4];
 413         struct i2c_msg m = {.addr = mst->i2c_addr,.buf = tx,.len = 4 };
 414
 415         dibx000_i2c_gate_ctrl(mst, tx, 0, 0);
 416         i2c_transfer(mst->i2c_adap, &m, 1);
 417         mst->selected_interface = 0xff; // the first time force a select of the I2C
 418         dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
 419 }
 420
 421 EXPORT_SYMBOL(dibx000_reset_i2c_master);
 422
 423 static int i2c_adapter_init(struct i2c_adapter *i2c_adap,
 424                                 struct i2c_algorithm *algo, const char *name,
 425                                 struct dibx000_i2c_master *mst)
 426 {
 427         strncpy(i2c_adap->name, name, sizeof(i2c_adap->name));
 428         i2c_adap->algo = algo;
 429         i2c_adap->algo_data = NULL;
 430         i2c_set_adapdata(i2c_adap, mst);
 431         if (i2c_add_adapter(i2c_adap) < 0)
 432                 return -ENODEV;
 433         return 0;
 434 }
 435
 436 int dibx000_init_i2c_master(struct dibx000_i2c_master *mst, u16 device_rev,
 437                                 struct i2c_adapter *i2c_adap, u8 i2c_addr)
 438 {
 439         int ret;
 440
 441         mutex_init(&mst->i2c_buffer_lock);
 442         if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 443                 dprintk("could not acquire lock\n");
 444                 return -EINVAL;
 445         }
 446         memset(mst->msg, 0, sizeof(struct i2c_msg));
 447         mst->msg[0].addr = i2c_addr >> 1;
 448         mst->msg[0].flags = 0;
 449         mst->msg[0].buf = mst->i2c_write_buffer;
 450         mst->msg[0].len = 4;
 451
 452         mst->device_rev = device_rev;
 453         mst->i2c_adap = i2c_adap;
 454         mst->i2c_addr = i2c_addr >> 1;
 455
 456         if (device_rev == DIB7000P || device_rev == DIB8000)
 457                 mst->base_reg = 1024;
 458         else
 459                 mst->base_reg = 768;
 460
 461         mst->gated_tuner_i2c_adap.dev.parent = mst->i2c_adap->dev.parent;
 462         if (i2c_adapter_init
 463                         (&mst->gated_tuner_i2c_adap, &dibx000_i2c_gated_tuner_algo,
 464                          "DiBX000 tuner I2C bus", mst) != 0)
 465                 pr_err("could not initialize the tuner i2c_adapter\n");
 466
 467         mst->master_i2c_adap_gpio12.dev.parent = mst->i2c_adap->dev.parent;
 468         if (i2c_adapter_init
 469                         (&mst->master_i2c_adap_gpio12, &dibx000_i2c_master_gpio12_xfer_algo,
 470                          "DiBX000 master GPIO12 I2C bus", mst) != 0)
 471                 pr_err("could not initialize the master i2c_adapter\n");
 472
 473         mst->master_i2c_adap_gpio34.dev.parent = mst->i2c_adap->dev.parent;
 474         if (i2c_adapter_init
 475                         (&mst->master_i2c_adap_gpio34, &dibx000_i2c_master_gpio34_xfer_algo,
 476                          "DiBX000 master GPIO34 I2C bus", mst) != 0)
 477                 pr_err("could not initialize the master i2c_adapter\n");
 478
 479         mst->master_i2c_adap_gpio67.dev.parent = mst->i2c_adap->dev.parent;
 480         if (i2c_adapter_init
 481                         (&mst->master_i2c_adap_gpio67, &dibx000_i2c_gated_gpio67_algo,
 482                          "DiBX000 master GPIO67 I2C bus", mst) != 0)
 483                 pr_err("could not initialize the master i2c_adapter\n");
 484
 485         /* initialize the i2c-master by closing the gate */
 486         dibx000_i2c_gate_ctrl(mst, mst->i2c_write_buffer, 0, 0);
 487
 488         ret = (i2c_transfer(i2c_adap, mst->msg, 1) == 1);
 489         mutex_unlock(&mst->i2c_buffer_lock);
 490
 491         return ret;
 492 }
 493
 494 EXPORT_SYMBOL(dibx000_init_i2c_master);
 495
 496 void dibx000_exit_i2c_master(struct dibx000_i2c_master *mst)
 497 {
 498         i2c_del_adapter(&mst->gated_tuner_i2c_adap);
 499         i2c_del_adapter(&mst->master_i2c_adap_gpio12);
 500         i2c_del_adapter(&mst->master_i2c_adap_gpio34);
 501         i2c_del_adapter(&mst->master_i2c_adap_gpio67);
 502 }
 503 EXPORT_SYMBOL(dibx000_exit_i2c_master);
 504
 505 MODULE_AUTHOR("Patrick Boettcher <patrick.boettcher@posteo.de>");
 506 MODULE_DESCRIPTION("Common function the DiBcom demodulator family");
 507 MODULE_LICENSE("GPL");