linux/drivers/media/video/bt8xx/bttv-i2c.c
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   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
  39static int i2c_debug;
  40static int i2c_hw;
  41static int i2c_scan;
  42module_param(i2c_debug, int, 0644);
  43MODULE_PARM_DESC(i2c_debug, "configure i2c debug level");
  44module_param(i2c_hw,    int, 0444);
  45MODULE_PARM_DESC(i2c_hw,"force use of hardware i2c support, "
  46                        "instead of software bitbang");
  47module_param(i2c_scan,  int, 0444);
  48MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
  49
  50static unsigned int i2c_udelay = 5;
  51module_param(i2c_udelay, int, 0444);
  52MODULE_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
  58static 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
  70static 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
  82static 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
  91static 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
 100static 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
 112static u32 functionality(struct i2c_adapter *adap)
 113{
 114        return I2C_FUNC_SMBUS_EMUL;
 115}
 116
 117static int
 118bttv_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
 136static int
 137bttv_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
 189static int
 190bttv_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
 229static 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
 258static 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 */
 267int 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 */
 292int 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 */
 309void __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
 318static 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
 328static 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 */
 344int __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}
 392