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 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/delay.h>
  33
  34 #include "bttvp.h"
  35 #include <media/v4l2-common.h>
  36 #include <linux/jiffies.h>
  37 #include <asm/io.h>
  38
  39 static int i2c_debug;
  40 static int i2c_hw;
  41 static int i2c_scan;
  42 module_param(i2c_debug, int, 0644);
  43 MODULE_PARM_DESC(i2c_debug, "configure i2c debug level");
  44 module_param(i2c_hw,    int, 0444);
  45 MODULE_PARM_DESC(i2c_hw,"force use of hardware i2c support, "
  46                         "instead of software bitbang");
  47 module_param(i2c_scan,  int, 0444);
  48 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
  49
  50 static unsigned int i2c_udelay = 5;
  51 module_param(i2c_udelay, int, 0444);
  52 MODULE_PARM_DESC(i2c_udelay,"soft i2c delay at insmod time, in usecs "
  53                 "(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 struct i2c_algo_bit_data __devinitdata 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                 printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 158                 if (!(xmit & BT878_I2C_NOSTOP))
 159                         printk(" >\n");
 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                         printk(" %02x", msg->buf[cnt]);
 175                         if (!(xmit & BT878_I2C_NOSTOP))
 176                                 printk(" >\n");
 177                 }
 178         }
 179         return msg->len;
 180
 181  eio:
 182         retval = -EIO;
 183  err:
 184         if (i2c_debug)
 185                 printk(" ERR: %d\n",retval);
 186         return retval;
 187 }
 188
 189 static int
 190 bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
 191 {
 192         u32 xmit;
 193         u32 cnt;
 194         int retval;
 195
 196         for(cnt = 0; cnt < msg->len; cnt++) {
 197                 xmit = (msg->addr << 25) | (1 << 24) | I2C_HW;
 198                 if (cnt < msg->len-1)
 199                         xmit |= BT848_I2C_W3B;
 200                 if (cnt < msg->len-1 || !last)
 201                         xmit |= BT878_I2C_NOSTOP;
 202                 if (cnt)
 203                         xmit |= BT878_I2C_NOSTART;
 204                 btwrite(xmit, BT848_I2C);
 205                 retval = bttv_i2c_wait_done(btv);
 206                 if (retval < 0)
 207                         goto err;
 208                 if (retval == 0)
 209                         goto eio;
 210                 msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff;
 211                 if (i2c_debug) {
 212                         if (!(xmit & BT878_I2C_NOSTART))
 213                                 printk(" <R %02x", (msg->addr << 1) +1);
 214                         printk(" =%02x", msg->buf[cnt]);
 215                         if (!(xmit & BT878_I2C_NOSTOP))
 216                                 printk(" >\n");
 217                 }
 218         }
 219         return msg->len;
 220
 221  eio:
 222         retval = -EIO;
 223  err:
 224         if (i2c_debug)
 225                 printk(" ERR: %d\n",retval);
 226         return retval;
 227 }
 228
 229 static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
 230 {
 231         struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
 232         struct bttv *btv = to_bttv(v4l2_dev);
 233         int retval = 0;
 234         int i;
 235
 236         if (i2c_debug)
 237                 printk("bt-i2c:");
 238         btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT);
 239         for (i = 0 ; i < num; i++) {
 240                 if (msgs[i].flags & I2C_M_RD) {
 241                         /* read */
 242                         retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num);
 243                         if (retval < 0)
 244                                 goto err;
 245                 } else {
 246                         /* write */
 247                         retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num);
 248                         if (retval < 0)
 249                                 goto err;
 250                 }
 251         }
 252         return num;
 253
 254  err:
 255         return retval;
 256 }
 257
 258 static const struct i2c_algorithm bttv_algo = {
 259         .master_xfer   = bttv_i2c_xfer,
 260         .functionality = functionality,
 261 };
 262
 263 /* ----------------------------------------------------------------------- */
 264 /* I2C functions - common stuff                                            */
 265
 266 /* read I2C */
 267 int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for)
 268 {
 269         unsigned char buffer = 0;
 270
 271         if (0 != btv->i2c_rc)
 272                 return -1;
 273         if (bttv_verbose && NULL != probe_for)
 274                 printk(KERN_INFO "bttv%d: i2c: checking for %s @ 0x%02x... ",
 275                        btv->c.nr,probe_for,addr);
 276         btv->i2c_client.addr = addr >> 1;
 277         if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) {
 278                 if (NULL != probe_for) {
 279                         if (bttv_verbose)
 280                                 printk("not found\n");
 281                 } else
 282                         printk(KERN_WARNING "bttv%d: i2c read 0x%x: error\n",
 283                                btv->c.nr,addr);
 284                 return -1;
 285         }
 286         if (bttv_verbose && NULL != probe_for)
 287                 printk("found\n");
 288         return buffer;
 289 }
 290
 291 /* write I2C */
 292 int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
 293                     unsigned char b2, int both)
 294 {
 295         unsigned char buffer[2];
 296         int bytes = both ? 2 : 1;
 297
 298         if (0 != btv->i2c_rc)
 299                 return -1;
 300         btv->i2c_client.addr = addr >> 1;
 301         buffer[0] = b1;
 302         buffer[1] = b2;
 303         if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes))
 304                 return -1;
 305         return 0;
 306 }
 307
 308 /* read EEPROM content */
 309 void __devinit bttv_readee(struct bttv *btv, unsigned char *eedata, int addr)
 310 {
 311         memset(eedata, 0, 256);
 312         if (0 != btv->i2c_rc)
 313                 return;
 314         btv->i2c_client.addr = addr >> 1;
 315         tveeprom_read(&btv->i2c_client, eedata, 256);
 316 }
 317
 318 static char *i2c_devs[128] = {
 319         [ 0x1c >> 1 ] = "lgdt330x",
 320         [ 0x30 >> 1 ] = "IR (hauppauge)",
 321         [ 0x80 >> 1 ] = "msp34xx",
 322         [ 0x86 >> 1 ] = "tda9887",
 323         [ 0xa0 >> 1 ] = "eeprom",
 324         [ 0xc0 >> 1 ] = "tuner (analog)",
 325         [ 0xc2 >> 1 ] = "tuner (analog)",
 326 };
 327
 328 static void do_i2c_scan(char *name, struct i2c_client *c)
 329 {
 330         unsigned char buf;
 331         int i,rc;
 332
 333         for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
 334                 c->addr = i;
 335                 rc = i2c_master_recv(c,&buf,0);
 336                 if (rc < 0)
 337                         continue;
 338                 printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
 339                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 340         }
 341 }
 342
 343 /* init + register i2c algo-bit adapter */
 344 int __devinit init_bttv_i2c(struct bttv *btv)
 345 {
 346         strlcpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE);
 347
 348         if (i2c_hw)
 349                 btv->use_i2c_hw = 1;
 350         if (btv->use_i2c_hw) {
 351                 /* bt878 */
 352                 strlcpy(btv->c.i2c_adap.name, "bt878",
 353                         sizeof(btv->c.i2c_adap.name));
 354                 btv->c.i2c_adap.algo = &bttv_algo;
 355         } else {
 356                 /* bt848 */
 357         /* Prevents usage of invalid delay values */
 358                 if (i2c_udelay<5)
 359                         i2c_udelay=5;
 360
 361                 strlcpy(btv->c.i2c_adap.name, "bttv",
 362                         sizeof(btv->c.i2c_adap.name));
 363                 memcpy(&btv->i2c_algo, &bttv_i2c_algo_bit_template,
 364                        sizeof(bttv_i2c_algo_bit_template));
 365                 btv->i2c_algo.udelay = i2c_udelay;
 366                 btv->i2c_algo.data = btv;
 367                 btv->c.i2c_adap.algo_data = &btv->i2c_algo;
 368         }
 369         btv->c.i2c_adap.owner = THIS_MODULE;
 370
 371         btv->c.i2c_adap.dev.parent = &btv->c.pci->dev;
 372         snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name),
 373                  "bt%d #%d [%s]", btv->id, btv->c.nr,
 374                  btv->use_i2c_hw ? "hw" : "sw");
 375
 376         i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev);
 377         btv->i2c_client.adapter = &btv->c.i2c_adap;
 378
 379
 380         if (btv->use_i2c_hw) {
 381                 btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap);
 382         } else {
 383                 bttv_bit_setscl(btv,1);
 384                 bttv_bit_setsda(btv,1);
 385                 btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap);
 386         }
 387         if (0 == btv->i2c_rc && i2c_scan)
 388                 do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client);
 389
 390         return btv->i2c_rc;
 391 }