drivers/media/video/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@infradead.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, "
  48                         "instead of software bitbang");
  49 module_param(i2c_scan,  int, 0444);
  50 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
  51
  52 static unsigned int i2c_udelay = 5;
  53 module_param(i2c_udelay, int, 0444);
  54 MODULE_PARM_DESC(i2c_udelay,"soft i2c delay at insmod time, in usecs "
  55                 "(should be 5 or higher). Lower value means higher bus speed.");
  56
  57 /* ----------------------------------------------------------------------- */
  58 /* I2C functions - bitbanging adapter (software i2c)                       */
  59
  60 static void bttv_bit_setscl(void *data, int state)
  61 {
  62         struct bttv *btv = (struct bttv*)data;
  63
  64         if (state)
  65                 btv->i2c_state |= 0x02;
  66         else
  67                 btv->i2c_state &= ~0x02;
  68         btwrite(btv->i2c_state, BT848_I2C);
  69         btread(BT848_I2C);
  70 }
  71
  72 static void bttv_bit_setsda(void *data, int state)
  73 {
  74         struct bttv *btv = (struct bttv*)data;
  75
  76         if (state)
  77                 btv->i2c_state |= 0x01;
  78         else
  79                 btv->i2c_state &= ~0x01;
  80         btwrite(btv->i2c_state, BT848_I2C);
  81         btread(BT848_I2C);
  82 }
  83
  84 static int bttv_bit_getscl(void *data)
  85 {
  86         struct bttv *btv = (struct bttv*)data;
  87         int state;
  88
  89         state = btread(BT848_I2C) & 0x02 ? 1 : 0;
  90         return state;
  91 }
  92
  93 static int bttv_bit_getsda(void *data)
  94 {
  95         struct bttv *btv = (struct bttv*)data;
  96         int state;
  97
  98         state = btread(BT848_I2C) & 0x01;
  99         return state;
 100 }
 101
 102 static struct i2c_algo_bit_data __devinitdata bttv_i2c_algo_bit_template = {
 103         .setsda  = bttv_bit_setsda,
 104         .setscl  = bttv_bit_setscl,
 105         .getsda  = bttv_bit_getsda,
 106         .getscl  = bttv_bit_getscl,
 107         .udelay  = 16,
 108         .timeout = 200,
 109 };
 110
 111 /* ----------------------------------------------------------------------- */
 112 /* I2C functions - hardware i2c                                            */
 113
 114 static u32 functionality(struct i2c_adapter *adap)
 115 {
 116         return I2C_FUNC_SMBUS_EMUL;
 117 }
 118
 119 static int
 120 bttv_i2c_wait_done(struct bttv *btv)
 121 {
 122         int rc = 0;
 123
 124         /* timeout */
 125         if (wait_event_interruptible_timeout(btv->i2c_queue,
 126             btv->i2c_done, msecs_to_jiffies(85)) == -ERESTARTSYS)
 127                 rc = -EIO;
 128
 129         if (btv->i2c_done & BT848_INT_RACK)
 130                 rc = 1;
 131         btv->i2c_done = 0;
 132         return rc;
 133 }
 134
 135 #define I2C_HW (BT878_I2C_MODE  | BT848_I2C_SYNC |\
 136                 BT848_I2C_SCL | BT848_I2C_SDA)
 137
 138 static int
 139 bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
 140 {
 141         u32 xmit;
 142         int retval,cnt;
 143
 144         /* sanity checks */
 145         if (0 == msg->len)
 146                 return -EINVAL;
 147
 148         /* start, address + first byte */
 149         xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW;
 150         if (msg->len > 1 || !last)
 151                 xmit |= BT878_I2C_NOSTOP;
 152         btwrite(xmit, BT848_I2C);
 153         retval = bttv_i2c_wait_done(btv);
 154         if (retval < 0)
 155                 goto err;
 156         if (retval == 0)
 157                 goto eio;
 158         if (i2c_debug) {
 159                 pr_cont(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 160         }
 161
 162         for (cnt = 1; cnt < msg->len; cnt++ ) {
 163                 /* following bytes */
 164                 xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART;
 165                 if (cnt < msg->len-1 || !last)
 166                         xmit |= BT878_I2C_NOSTOP;
 167                 btwrite(xmit, BT848_I2C);
 168                 retval = bttv_i2c_wait_done(btv);
 169                 if (retval < 0)
 170                         goto err;
 171                 if (retval == 0)
 172                         goto eio;
 173                 if (i2c_debug)
 174                         pr_cont(" %02x", msg->buf[cnt]);
 175         }
 176         if (!(xmit & BT878_I2C_NOSTOP))
 177                 pr_cont(">\n");
 178         return msg->len;
 179
 180  eio:
 181         retval = -EIO;
 182  err:
 183         if (i2c_debug)
 184                 pr_cont(" ERR: %d\n",retval);
 185         return retval;
 186 }
 187
 188 static int
 189 bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
 190 {
 191         u32 xmit;
 192         u32 cnt;
 193         int retval;
 194
 195         for (cnt = 0; cnt < msg->len; cnt++) {
 196                 xmit = (msg->addr << 25) | (1 << 24) | I2C_HW;
 197                 if (cnt < msg->len-1)
 198                         xmit |= BT848_I2C_W3B;
 199                 if (cnt < msg->len-1 || !last)
 200                         xmit |= BT878_I2C_NOSTOP;
 201                 if (cnt)
 202                         xmit |= BT878_I2C_NOSTART;
 203
 204                 if (i2c_debug) {
 205                         if (!(xmit & BT878_I2C_NOSTART))
 206                                 pr_cont(" <R %02x", (msg->addr << 1) +1);
 207                 }
 208
 209                 btwrite(xmit, BT848_I2C);
 210                 retval = bttv_i2c_wait_done(btv);
 211                 if (retval < 0)
 212                         goto err;
 213                 if (retval == 0)
 214                         goto eio;
 215                 msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff;
 216                 if (i2c_debug) {
 217                         pr_cont(" =%02x", msg->buf[cnt]);
 218                 }
 219                 if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
 220                         pr_cont(" >\n");
 221         }
 222
 223
 224         return msg->len;
 225
 226  eio:
 227         retval = -EIO;
 228  err:
 229         if (i2c_debug)
 230                 pr_cont(" ERR: %d\n",retval);
 231         return retval;
 232 }
 233
 234 static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
 235 {
 236         struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
 237         struct bttv *btv = to_bttv(v4l2_dev);
 238         int retval = 0;
 239         int i;
 240
 241         if (i2c_debug)
 242                 pr_debug("bt-i2c:");
 243
 244         btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT);
 245         for (i = 0 ; i < num; i++) {
 246                 if (msgs[i].flags & I2C_M_RD) {
 247                         /* read */
 248                         retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num);
 249                         if (retval < 0)
 250                                 goto err;
 251                 } else {
 252                         /* write */
 253                         retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num);
 254                         if (retval < 0)
 255                                 goto err;
 256                 }
 257         }
 258         return num;
 259
 260  err:
 261         return retval;
 262 }
 263
 264 static const struct i2c_algorithm bttv_algo = {
 265         .master_xfer   = bttv_i2c_xfer,
 266         .functionality = functionality,
 267 };
 268
 269 /* ----------------------------------------------------------------------- */
 270 /* I2C functions - common stuff                                            */
 271
 272 /* read I2C */
 273 int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for)
 274 {
 275         unsigned char buffer = 0;
 276
 277         if (0 != btv->i2c_rc)
 278                 return -1;
 279         if (bttv_verbose && NULL != probe_for)
 280                 pr_info("%d: i2c: checking for %s @ 0x%02x... ",
 281                         btv->c.nr, probe_for, addr);
 282         btv->i2c_client.addr = addr >> 1;
 283         if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) {
 284                 if (NULL != probe_for) {
 285                         if (bttv_verbose)
 286                                 pr_cont("not found\n");
 287                 } else
 288                         pr_warn("%d: i2c read 0x%x: error\n",
 289                                 btv->c.nr, addr);
 290                 return -1;
 291         }
 292         if (bttv_verbose && NULL != probe_for)
 293                 pr_cont("found\n");
 294         return buffer;
 295 }
 296
 297 /* write I2C */
 298 int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
 299                     unsigned char b2, int both)
 300 {
 301         unsigned char buffer[2];
 302         int bytes = both ? 2 : 1;
 303
 304         if (0 != btv->i2c_rc)
 305                 return -1;
 306         btv->i2c_client.addr = addr >> 1;
 307         buffer[0] = b1;
 308         buffer[1] = b2;
 309         if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes))
 310                 return -1;
 311         return 0;
 312 }
 313
 314 /* read EEPROM content */
 315 void __devinit bttv_readee(struct bttv *btv, unsigned char *eedata, int addr)
 316 {
 317         memset(eedata, 0, 256);
 318         if (0 != btv->i2c_rc)
 319                 return;
 320         btv->i2c_client.addr = addr >> 1;
 321         tveeprom_read(&btv->i2c_client, eedata, 256);
 322 }
 323
 324 static char *i2c_devs[128] = {
 325         [ 0x1c >> 1 ] = "lgdt330x",
 326         [ 0x30 >> 1 ] = "IR (hauppauge)",
 327         [ 0x80 >> 1 ] = "msp34xx",
 328         [ 0x86 >> 1 ] = "tda9887",
 329         [ 0xa0 >> 1 ] = "eeprom",
 330         [ 0xc0 >> 1 ] = "tuner (analog)",
 331         [ 0xc2 >> 1 ] = "tuner (analog)",
 332 };
 333
 334 static void do_i2c_scan(char *name, struct i2c_client *c)
 335 {
 336         unsigned char buf;
 337         int i,rc;
 338
 339         for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
 340                 c->addr = i;
 341                 rc = i2c_master_recv(c,&buf,0);
 342                 if (rc < 0)
 343                         continue;
 344                 pr_info("%s: i2c scan: found device @ 0x%x  [%s]\n",
 345                         name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 346         }
 347 }
 348
 349 /* init + register i2c adapter */
 350 int __devinit init_bttv_i2c(struct bttv *btv)
 351 {
 352         strlcpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE);
 353
 354         if (i2c_hw)
 355                 btv->use_i2c_hw = 1;
 356         if (btv->use_i2c_hw) {
 357                 /* bt878 */
 358                 strlcpy(btv->c.i2c_adap.name, "bt878",
 359                         sizeof(btv->c.i2c_adap.name));
 360                 btv->c.i2c_adap.algo = &bttv_algo;
 361         } else {
 362                 /* bt848 */
 363         /* Prevents usage of invalid delay values */
 364                 if (i2c_udelay<5)
 365                         i2c_udelay=5;
 366
 367                 strlcpy(btv->c.i2c_adap.name, "bttv",
 368                         sizeof(btv->c.i2c_adap.name));
 369                 memcpy(&btv->i2c_algo, &bttv_i2c_algo_bit_template,
 370                        sizeof(bttv_i2c_algo_bit_template));
 371                 btv->i2c_algo.udelay = i2c_udelay;
 372                 btv->i2c_algo.data = btv;
 373                 btv->c.i2c_adap.algo_data = &btv->i2c_algo;
 374         }
 375         btv->c.i2c_adap.owner = THIS_MODULE;
 376
 377         btv->c.i2c_adap.dev.parent = &btv->c.pci->dev;
 378         snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name),
 379                  "bt%d #%d [%s]", btv->id, btv->c.nr,
 380                  btv->use_i2c_hw ? "hw" : "sw");
 381
 382         i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev);
 383         btv->i2c_client.adapter = &btv->c.i2c_adap;
 384
 385
 386         if (btv->use_i2c_hw) {
 387                 btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap);
 388         } else {
 389                 bttv_bit_setscl(btv,1);
 390                 bttv_bit_setsda(btv,1);
 391                 btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap);
 392         }
 393         if (0 == btv->i2c_rc && i2c_scan)
 394                 do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client);
 395
 396         return btv->i2c_rc;
 397 }