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
 126         rc = -EIO;
 127
 128         if (btv->i2c_done & BT848_INT_RACK)
 129                 rc = 1;
 130         btv->i2c_done = 0;
 131         return rc;
 132 }
 133
 134 #define I2C_HW (BT878_I2C_MODE  | BT848_I2C_SYNC |\
 135                 BT848_I2C_SCL | BT848_I2C_SDA)
 136
 137 static int
 138 bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
 139 {
 140         u32 xmit;
 141         int retval,cnt;
 142
 143         /* sanity checks */
 144         if (0 == msg->len)
 145                 return -EINVAL;
 146
 147         /* start, address + first byte */
 148         xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW;
 149         if (msg->len > 1 || !last)
 150                 xmit |= BT878_I2C_NOSTOP;
 151         btwrite(xmit, BT848_I2C);
 152         retval = bttv_i2c_wait_done(btv);
 153         if (retval < 0)
 154                 goto err;
 155         if (retval == 0)
 156                 goto eio;
 157         if (i2c_debug) {
 158                 printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 159                 if (!(xmit & BT878_I2C_NOSTOP))
 160                         printk(" >\n");
 161         }
 162
 163         for (cnt = 1; cnt < msg->len; cnt++ ) {
 164                 /* following bytes */
 165                 xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART;
 166                 if (cnt < msg->len-1 || !last)
 167                         xmit |= BT878_I2C_NOSTOP;
 168                 btwrite(xmit, BT848_I2C);
 169                 retval = bttv_i2c_wait_done(btv);
 170                 if (retval < 0)
 171                         goto err;
 172                 if (retval == 0)
 173                         goto eio;
 174                 if (i2c_debug) {
 175                         printk(" %02x", msg->buf[cnt]);
 176                         if (!(xmit & BT878_I2C_NOSTOP))
 177                                 printk(" >\n");
 178                 }
 179         }
 180         return msg->len;
 181
 182  eio:
 183         retval = -EIO;
 184  err:
 185         if (i2c_debug)
 186                 printk(" ERR: %d\n",retval);
 187         return retval;
 188 }
 189
 190 static int
 191 bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
 192 {
 193         u32 xmit;
 194         u32 cnt;
 195         int retval;
 196
 197         for(cnt = 0; cnt < msg->len; cnt++) {
 198                 xmit = (msg->addr << 25) | (1 << 24) | I2C_HW;
 199                 if (cnt < msg->len-1)
 200                         xmit |= BT848_I2C_W3B;
 201                 if (cnt < msg->len-1 || !last)
 202                         xmit |= BT878_I2C_NOSTOP;
 203                 if (cnt)
 204                         xmit |= BT878_I2C_NOSTART;
 205                 btwrite(xmit, BT848_I2C);
 206                 retval = bttv_i2c_wait_done(btv);
 207                 if (retval < 0)
 208                         goto err;
 209                 if (retval == 0)
 210                         goto eio;
 211                 msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff;
 212                 if (i2c_debug) {
 213                         if (!(xmit & BT878_I2C_NOSTART))
 214                                 printk(" <R %02x", (msg->addr << 1) +1);
 215                         printk(" =%02x", msg->buf[cnt]);
 216                         if (!(xmit & BT878_I2C_NOSTOP))
 217                                 printk(" >\n");
 218                 }
 219         }
 220         return msg->len;
 221
 222  eio:
 223         retval = -EIO;
 224  err:
 225         if (i2c_debug)
 226                 printk(" ERR: %d\n",retval);
 227         return retval;
 228 }
 229
 230 static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
 231 {
 232         struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
 233         struct bttv *btv = to_bttv(v4l2_dev);
 234         int retval = 0;
 235         int i;
 236
 237         if (i2c_debug)
 238                 printk("bt-i2c:");
 239         btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT);
 240         for (i = 0 ; i < num; i++) {
 241                 if (msgs[i].flags & I2C_M_RD) {
 242                         /* read */
 243                         retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num);
 244                         if (retval < 0)
 245                                 goto err;
 246                 } else {
 247                         /* write */
 248                         retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num);
 249                         if (retval < 0)
 250                                 goto err;
 251                 }
 252         }
 253         return num;
 254
 255  err:
 256         return retval;
 257 }
 258
 259 static const struct i2c_algorithm bttv_algo = {
 260         .master_xfer   = bttv_i2c_xfer,
 261         .functionality = functionality,
 262 };
 263
 264 /* ----------------------------------------------------------------------- */
 265 /* I2C functions - common stuff                                            */
 266
 267 /* read I2C */
 268 int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for)
 269 {
 270         unsigned char buffer = 0;
 271
 272         if (0 != btv->i2c_rc)
 273                 return -1;
 274         if (bttv_verbose && NULL != probe_for)
 275                 printk(KERN_INFO "bttv%d: i2c: checking for %s @ 0x%02x... ",
 276                        btv->c.nr,probe_for,addr);
 277         btv->i2c_client.addr = addr >> 1;
 278         if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) {
 279                 if (NULL != probe_for) {
 280                         if (bttv_verbose)
 281                                 printk("not found\n");
 282                 } else
 283                         printk(KERN_WARNING "bttv%d: i2c read 0x%x: error\n",
 284                                btv->c.nr,addr);
 285                 return -1;
 286         }
 287         if (bttv_verbose && NULL != probe_for)
 288                 printk("found\n");
 289         return buffer;
 290 }
 291
 292 /* write I2C */
 293 int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
 294                     unsigned char b2, int both)
 295 {
 296         unsigned char buffer[2];
 297         int bytes = both ? 2 : 1;
 298
 299         if (0 != btv->i2c_rc)
 300                 return -1;
 301         btv->i2c_client.addr = addr >> 1;
 302         buffer[0] = b1;
 303         buffer[1] = b2;
 304         if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes))
 305                 return -1;
 306         return 0;
 307 }
 308
 309 /* read EEPROM content */
 310 void __devinit bttv_readee(struct bttv *btv, unsigned char *eedata, int addr)
 311 {
 312         memset(eedata, 0, 256);
 313         if (0 != btv->i2c_rc)
 314                 return;
 315         btv->i2c_client.addr = addr >> 1;
 316         tveeprom_read(&btv->i2c_client, eedata, 256);
 317 }
 318
 319 static char *i2c_devs[128] = {
 320         [ 0x1c >> 1 ] = "lgdt330x",
 321         [ 0x30 >> 1 ] = "IR (hauppauge)",
 322         [ 0x80 >> 1 ] = "msp34xx",
 323         [ 0x86 >> 1 ] = "tda9887",
 324         [ 0xa0 >> 1 ] = "eeprom",
 325         [ 0xc0 >> 1 ] = "tuner (analog)",
 326         [ 0xc2 >> 1 ] = "tuner (analog)",
 327 };
 328
 329 static void do_i2c_scan(char *name, struct i2c_client *c)
 330 {
 331         unsigned char buf;
 332         int i,rc;
 333
 334         for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
 335                 c->addr = i;
 336                 rc = i2c_master_recv(c,&buf,0);
 337                 if (rc < 0)
 338                         continue;
 339                 printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
 340                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 341         }
 342 }
 343
 344 /* init + register i2c algo-bit adapter */
 345 int __devinit init_bttv_i2c(struct bttv *btv)
 346 {
 347         strlcpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE);
 348
 349         if (i2c_hw)
 350                 btv->use_i2c_hw = 1;
 351         if (btv->use_i2c_hw) {
 352                 /* bt878 */
 353                 strlcpy(btv->c.i2c_adap.name, "bt878",
 354                         sizeof(btv->c.i2c_adap.name));
 355                 btv->c.i2c_adap.algo = &bttv_algo;
 356         } else {
 357                 /* bt848 */
 358         /* Prevents usage of invalid delay values */
 359                 if (i2c_udelay<5)
 360                         i2c_udelay=5;
 361
 362                 strlcpy(btv->c.i2c_adap.name, "bttv",
 363                         sizeof(btv->c.i2c_adap.name));
 364                 memcpy(&btv->i2c_algo, &bttv_i2c_algo_bit_template,
 365                        sizeof(bttv_i2c_algo_bit_template));
 366                 btv->i2c_algo.udelay = i2c_udelay;
 367                 btv->i2c_algo.data = btv;
 368                 btv->c.i2c_adap.algo_data = &btv->i2c_algo;
 369         }
 370         btv->c.i2c_adap.owner = THIS_MODULE;
 371
 372         btv->c.i2c_adap.dev.parent = &btv->c.pci->dev;
 373         snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name),
 374                  "bt%d #%d [%s]", btv->id, btv->c.nr,
 375                  btv->use_i2c_hw ? "hw" : "sw");
 376
 377         i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev);
 378         btv->i2c_client.adapter = &btv->c.i2c_adap;
 379
 380
 381         if (btv->use_i2c_hw) {
 382                 btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap);
 383         } else {
 384                 bttv_bit_setscl(btv,1);
 385                 bttv_bit_setsda(btv,1);
 386                 btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap);
 387         }
 388         if (0 == btv->i2c_rc && i2c_scan)
 389                 do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client);
 390
 391         return btv->i2c_rc;
 392 }