drivers/media/pci/bt8xx/bttv-i2c.c

   1 /*
   2
   3     bttv-i2c.c  --  all the i2c code is here
   4
   5     bttv - Bt848 frame grabber driver
   6
   7     Copyright (C) 1996,97,98 Ralph  Metzler (rjkm@thp.uni-koeln.de)
   8                            & Marcus Metzler (mocm@thp.uni-koeln.de)
   9     (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>
  10
  11     (c) 2005 Mauro Carvalho Chehab <mchehab@kernel.org>
  12         - Multituner support and i2c address binding
  13
  14     This program is free software; you can redistribute it and/or modify
  15     it under the terms of the GNU General Public License as published by
  16     the Free Software Foundation; either version 2 of the License, or
  17     (at your option) any later version.
  18
  19     This program is distributed in the hope that it will be useful,
  20     but WITHOUT ANY WARRANTY; without even the implied warranty of
  21     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22     GNU General Public License for more details.
  23
  24     You should have received a copy of the GNU General Public License
  25     along with this program; if not, write to the Free Software
  26     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  27
  28 */
  29
  30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  32 #include <linux/module.h>
  33 #include <linux/init.h>
  34 #include <linux/delay.h>
  35
  36 #include "bttvp.h"
  37 #include <media/v4l2-common.h>
  38 #include <linux/jiffies.h>
  39 #include <asm/io.h>
  40
  41 static int i2c_debug;
  42 static int i2c_hw;
  43 static int i2c_scan;
  44 module_param(i2c_debug, int, 0644);
  45 MODULE_PARM_DESC(i2c_debug, "configure i2c debug level");
  46 module_param(i2c_hw,    int, 0444);
  47 MODULE_PARM_DESC(i2c_hw, "force use of hardware i2c support, instead of software bitbang");
  48 module_param(i2c_scan,  int, 0444);
  49 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
  50
  51 static unsigned int i2c_udelay = 5;
  52 module_param(i2c_udelay, int, 0444);
  53 MODULE_PARM_DESC(i2c_udelay, "soft i2c delay at insmod time, in usecs (should be 5 or higher). Lower value means higher bus speed.");
  54
  55 /* ----------------------------------------------------------------------- */
  56 /* I2C functions - bitbanging adapter (software i2c)                       */
  57
  58 static void bttv_bit_setscl(void *data, int state)
  59 {
  60         struct bttv *btv = (struct bttv*)data;
  61
  62         if (state)
  63                 btv->i2c_state |= 0x02;
  64         else
  65                 btv->i2c_state &= ~0x02;
  66         btwrite(btv->i2c_state, BT848_I2C);
  67         btread(BT848_I2C);
  68 }
  69
  70 static void bttv_bit_setsda(void *data, int state)
  71 {
  72         struct bttv *btv = (struct bttv*)data;
  73
  74         if (state)
  75                 btv->i2c_state |= 0x01;
  76         else
  77                 btv->i2c_state &= ~0x01;
  78         btwrite(btv->i2c_state, BT848_I2C);
  79         btread(BT848_I2C);
  80 }
  81
  82 static int bttv_bit_getscl(void *data)
  83 {
  84         struct bttv *btv = (struct bttv*)data;
  85         int state;
  86
  87         state = btread(BT848_I2C) & 0x02 ? 1 : 0;
  88         return state;
  89 }
  90
  91 static int bttv_bit_getsda(void *data)
  92 {
  93         struct bttv *btv = (struct bttv*)data;
  94         int state;
  95
  96         state = btread(BT848_I2C) & 0x01;
  97         return state;
  98 }
  99
 100 static const struct i2c_algo_bit_data bttv_i2c_algo_bit_template = {
 101         .setsda  = bttv_bit_setsda,
 102         .setscl  = bttv_bit_setscl,
 103         .getsda  = bttv_bit_getsda,
 104         .getscl  = bttv_bit_getscl,
 105         .udelay  = 16,
 106         .timeout = 200,
 107 };
 108
 109 /* ----------------------------------------------------------------------- */
 110 /* I2C functions - hardware i2c                                            */
 111
 112 static u32 functionality(struct i2c_adapter *adap)
 113 {
 114         return I2C_FUNC_SMBUS_EMUL;
 115 }
 116
 117 static int
 118 bttv_i2c_wait_done(struct bttv *btv)
 119 {
 120         int rc = 0;
 121
 122         /* timeout */
 123         if (wait_event_interruptible_timeout(btv->i2c_queue,
 124             btv->i2c_done, msecs_to_jiffies(85)) == -ERESTARTSYS)
 125                 rc = -EIO;
 126
 127         if (btv->i2c_done & BT848_INT_RACK)
 128                 rc = 1;
 129         btv->i2c_done = 0;
 130         return rc;
 131 }
 132
 133 #define I2C_HW (BT878_I2C_MODE  | BT848_I2C_SYNC |\
 134                 BT848_I2C_SCL | BT848_I2C_SDA)
 135
 136 static int
 137 bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
 138 {
 139         u32 xmit;
 140         int retval,cnt;
 141
 142         /* sanity checks */
 143         if (0 == msg->len)
 144                 return -EINVAL;
 145
 146         /* start, address + first byte */
 147         xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW;
 148         if (msg->len > 1 || !last)
 149                 xmit |= BT878_I2C_NOSTOP;
 150         btwrite(xmit, BT848_I2C);
 151         retval = bttv_i2c_wait_done(btv);
 152         if (retval < 0)
 153                 goto err;
 154         if (retval == 0)
 155                 goto eio;
 156         if (i2c_debug) {
 157                 pr_cont(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 158         }
 159
 160         for (cnt = 1; cnt < msg->len; cnt++ ) {
 161                 /* following bytes */
 162                 xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART;
 163                 if (cnt < msg->len-1 || !last)
 164                         xmit |= BT878_I2C_NOSTOP;
 165                 btwrite(xmit, BT848_I2C);
 166                 retval = bttv_i2c_wait_done(btv);
 167                 if (retval < 0)
 168                         goto err;
 169                 if (retval == 0)
 170                         goto eio;
 171                 if (i2c_debug)
 172                         pr_cont(" %02x", msg->buf[cnt]);
 173         }
 174         if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
 175                 pr_cont(">\n");
 176         return msg->len;
 177
 178  eio:
 179         retval = -EIO;
 180  err:
 181         if (i2c_debug)
 182                 pr_cont(" ERR: %d\n",retval);
 183         return retval;
 184 }
 185
 186 static int
 187 bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
 188 {
 189         u32 xmit;
 190         u32 cnt;
 191         int retval;
 192
 193         for (cnt = 0; cnt < msg->len; cnt++) {
 194                 xmit = (msg->addr << 25) | (1 << 24) | I2C_HW;
 195                 if (cnt < msg->len-1)
 196                         xmit |= BT848_I2C_W3B;
 197                 if (cnt < msg->len-1 || !last)
 198                         xmit |= BT878_I2C_NOSTOP;
 199                 if (cnt)
 200                         xmit |= BT878_I2C_NOSTART;
 201
 202                 if (i2c_debug) {
 203                         if (!(xmit & BT878_I2C_NOSTART))
 204                                 pr_cont(" <R %02x", (msg->addr << 1) +1);
 205                 }
 206
 207                 btwrite(xmit, BT848_I2C);
 208                 retval = bttv_i2c_wait_done(btv);
 209                 if (retval < 0)
 210                         goto err;
 211                 if (retval == 0)
 212                         goto eio;
 213                 msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff;
 214                 if (i2c_debug) {
 215                         pr_cont(" =%02x", msg->buf[cnt]);
 216                 }
 217                 if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
 218                         pr_cont(" >\n");
 219         }
 220
 221
 222         return msg->len;
 223
 224  eio:
 225         retval = -EIO;
 226  err:
 227         if (i2c_debug)
 228                 pr_cont(" ERR: %d\n",retval);
 229         return retval;
 230 }
 231
 232 static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
 233 {
 234         struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
 235         struct bttv *btv = to_bttv(v4l2_dev);
 236         int retval = 0;
 237         int i;
 238
 239         if (i2c_debug)
 240                 pr_debug("bt-i2c:");
 241
 242         btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT);
 243         for (i = 0 ; i < num; i++) {
 244                 if (msgs[i].flags & I2C_M_RD) {
 245                         /* read */
 246                         retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num);
 247                         if (retval < 0)
 248                                 goto err;
 249                 } else {
 250                         /* write */
 251                         retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num);
 252                         if (retval < 0)
 253                                 goto err;
 254                 }
 255         }
 256         return num;
 257
 258  err:
 259         return retval;
 260 }
 261
 262 static const struct i2c_algorithm bttv_algo = {
 263         .master_xfer   = bttv_i2c_xfer,
 264         .functionality = functionality,
 265 };
 266
 267 /* ----------------------------------------------------------------------- */
 268 /* I2C functions - common stuff                                            */
 269
 270 /* read I2C */
 271 int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for)
 272 {
 273         unsigned char buffer = 0;
 274
 275         if (0 != btv->i2c_rc)
 276                 return -1;
 277         if (bttv_verbose && NULL != probe_for)
 278                 pr_info("%d: i2c: checking for %s @ 0x%02x... ",
 279                         btv->c.nr, probe_for, addr);
 280         btv->i2c_client.addr = addr >> 1;
 281         if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) {
 282                 if (NULL != probe_for) {
 283                         if (bttv_verbose)
 284                                 pr_cont("not found\n");
 285                 } else
 286                         pr_warn("%d: i2c read 0x%x: error\n",
 287                                 btv->c.nr, addr);
 288                 return -1;
 289         }
 290         if (bttv_verbose && NULL != probe_for)
 291                 pr_cont("found\n");
 292         return buffer;
 293 }
 294
 295 /* write I2C */
 296 int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
 297                     unsigned char b2, int both)
 298 {
 299         unsigned char buffer[2];
 300         int bytes = both ? 2 : 1;
 301
 302         if (0 != btv->i2c_rc)
 303                 return -1;
 304         btv->i2c_client.addr = addr >> 1;
 305         buffer[0] = b1;
 306         buffer[1] = b2;
 307         if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes))
 308                 return -1;
 309         return 0;
 310 }
 311
 312 /* read EEPROM content */
 313 void bttv_readee(struct bttv *btv, unsigned char *eedata, int addr)
 314 {
 315         memset(eedata, 0, 256);
 316         if (0 != btv->i2c_rc)
 317                 return;
 318         btv->i2c_client.addr = addr >> 1;
 319         tveeprom_read(&btv->i2c_client, eedata, 256);
 320 }
 321
 322 static char *i2c_devs[128] = {
 323         [ 0x1c >> 1 ] = "lgdt330x",
 324         [ 0x30 >> 1 ] = "IR (hauppauge)",
 325         [ 0x80 >> 1 ] = "msp34xx",
 326         [ 0x86 >> 1 ] = "tda9887",
 327         [ 0xa0 >> 1 ] = "eeprom",
 328         [ 0xc0 >> 1 ] = "tuner (analog)",
 329         [ 0xc2 >> 1 ] = "tuner (analog)",
 330 };
 331
 332 static void do_i2c_scan(char *name, struct i2c_client *c)
 333 {
 334         unsigned char buf;
 335         int i,rc;
 336
 337         for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
 338                 c->addr = i;
 339                 rc = i2c_master_recv(c,&buf,0);
 340                 if (rc < 0)
 341                         continue;
 342                 pr_info("%s: i2c scan: found device @ 0x%x  [%s]\n",
 343                         name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 344         }
 345 }
 346
 347 /* init + register i2c adapter */
 348 int init_bttv_i2c(struct bttv *btv)
 349 {
 350         strscpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE);
 351
 352         if (i2c_hw)
 353                 btv->use_i2c_hw = 1;
 354         if (btv->use_i2c_hw) {
 355                 /* bt878 */
 356                 strscpy(btv->c.i2c_adap.name, "bt878",
 357                         sizeof(btv->c.i2c_adap.name));
 358                 btv->c.i2c_adap.algo = &bttv_algo;
 359         } else {
 360                 /* bt848 */
 361         /* Prevents usage of invalid delay values */
 362                 if (i2c_udelay<5)
 363                         i2c_udelay=5;
 364
 365                 strscpy(btv->c.i2c_adap.name, "bttv",
 366                         sizeof(btv->c.i2c_adap.name));
 367                 btv->i2c_algo = bttv_i2c_algo_bit_template;
 368                 btv->i2c_algo.udelay = i2c_udelay;
 369                 btv->i2c_algo.data = btv;
 370                 btv->c.i2c_adap.algo_data = &btv->i2c_algo;
 371         }
 372         btv->c.i2c_adap.owner = THIS_MODULE;
 373
 374         btv->c.i2c_adap.dev.parent = &btv->c.pci->dev;
 375         snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name),
 376                  "bt%d #%d [%s]", btv->id, btv->c.nr,
 377                  btv->use_i2c_hw ? "hw" : "sw");
 378
 379         i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev);
 380         btv->i2c_client.adapter = &btv->c.i2c_adap;
 381
 382
 383         if (btv->use_i2c_hw) {
 384                 btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap);
 385         } else {
 386                 bttv_bit_setscl(btv,1);
 387                 bttv_bit_setsda(btv,1);
 388                 btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap);
 389         }
 390         if (0 == btv->i2c_rc && i2c_scan)
 391                 do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client);
 392
 393         return btv->i2c_rc;
 394 }
 395
 396 int fini_bttv_i2c(struct bttv *btv)
 397 {
 398         if (btv->i2c_rc == 0)
 399                 i2c_del_adapter(&btv->c.i2c_adap);
 400
 401         return 0;
 402 }