drivers/media/video/cx23885/cx23885-i2c.c

   1 /*
   2  *  Driver for the Conexant CX23885 PCIe bridge
   3  *
   4  *  Copyright (c) 2006 Steven Toth <stoth@linuxtv.org>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/moduleparam.h>
  24 #include <linux/init.h>
  25 #include <linux/delay.h>
  26 #include <asm/io.h>
  27
  28 #include "cx23885.h"
  29
  30 #include <media/v4l2-common.h>
  31
  32 static unsigned int i2c_debug;
  33 module_param(i2c_debug, int, 0644);
  34 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  35
  36 static unsigned int i2c_scan;
  37 module_param(i2c_scan, int, 0444);
  38 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
  39
  40 #define dprintk(level, fmt, arg...)\
  41         do { if (i2c_debug >= level)\
  42                 printk(KERN_DEBUG "%s/0: " fmt, dev->name, ## arg);\
  43         } while (0)
  44
  45 #define I2C_WAIT_DELAY 32
  46 #define I2C_WAIT_RETRY 64
  47
  48 #define I2C_EXTEND  (1 << 3)
  49 #define I2C_NOSTOP  (1 << 4)
  50
  51 static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
  52 {
  53         struct cx23885_i2c *bus = i2c_adap->algo_data;
  54         struct cx23885_dev *dev = bus->dev;
  55         return cx_read(bus->reg_stat) & 0x01;
  56 }
  57
  58 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
  59 {
  60         struct cx23885_i2c *bus = i2c_adap->algo_data;
  61         struct cx23885_dev *dev = bus->dev;
  62         return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
  63 }
  64
  65 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
  66 {
  67         int count;
  68
  69         for (count = 0; count < I2C_WAIT_RETRY; count++) {
  70                 if (!i2c_is_busy(i2c_adap))
  71                         break;
  72                 udelay(I2C_WAIT_DELAY);
  73         }
  74
  75         if (I2C_WAIT_RETRY == count)
  76                 return 0;
  77
  78         return 1;
  79 }
  80
  81 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
  82                          const struct i2c_msg *msg, int joined_rlen)
  83 {
  84         struct cx23885_i2c *bus = i2c_adap->algo_data;
  85         struct cx23885_dev *dev = bus->dev;
  86         u32 wdata, addr, ctrl;
  87         int retval, cnt;
  88
  89         if (joined_rlen)
  90                 dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__,
  91                         msg->len, joined_rlen);
  92         else
  93                 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
  94
  95         /* Deal with i2c probe functions with zero payload */
  96         if (msg->len == 0) {
  97                 cx_write(bus->reg_addr, msg->addr << 25);
  98                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
  99                 if (!i2c_wait_done(i2c_adap))
 100                         return -EIO;
 101                 if (!i2c_slave_did_ack(i2c_adap))
 102                         return -EIO;
 103
 104                 dprintk(1, "%s() returns 0\n", __func__);
 105                 return 0;
 106         }
 107
 108
 109         /* dev, reg + first byte */
 110         addr = (msg->addr << 25) | msg->buf[0];
 111         wdata = msg->buf[0];
 112         ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 113
 114         if (msg->len > 1)
 115                 ctrl |= I2C_NOSTOP | I2C_EXTEND;
 116         else if (joined_rlen)
 117                 ctrl |= I2C_NOSTOP;
 118
 119         cx_write(bus->reg_addr, addr);
 120         cx_write(bus->reg_wdata, wdata);
 121         cx_write(bus->reg_ctrl, ctrl);
 122
 123         retval = i2c_wait_done(i2c_adap);
 124         if (retval < 0)
 125                 goto err;
 126         if (retval == 0)
 127                 goto eio;
 128         if (i2c_debug) {
 129                 printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 130                 if (!(ctrl & I2C_NOSTOP))
 131                         printk(" >\n");
 132         }
 133
 134         for (cnt = 1; cnt < msg->len; cnt++) {
 135                 /* following bytes */
 136                 wdata = msg->buf[cnt];
 137                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 138
 139                 if (cnt < msg->len - 1)
 140                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 141                 else if (joined_rlen)
 142                         ctrl |= I2C_NOSTOP;
 143
 144                 cx_write(bus->reg_addr, addr);
 145                 cx_write(bus->reg_wdata, wdata);
 146                 cx_write(bus->reg_ctrl, ctrl);
 147
 148                 retval = i2c_wait_done(i2c_adap);
 149                 if (retval < 0)
 150                         goto err;
 151                 if (retval == 0)
 152                         goto eio;
 153                 if (i2c_debug) {
 154                         dprintk(1, " %02x", msg->buf[cnt]);
 155                         if (!(ctrl & I2C_NOSTOP))
 156                                 dprintk(1, " >\n");
 157                 }
 158         }
 159         return msg->len;
 160
 161  eio:
 162         retval = -EIO;
 163  err:
 164         if (i2c_debug)
 165                 printk(KERN_ERR " ERR: %d\n", retval);
 166         return retval;
 167 }
 168
 169 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
 170                          const struct i2c_msg *msg, int joined)
 171 {
 172         struct cx23885_i2c *bus = i2c_adap->algo_data;
 173         struct cx23885_dev *dev = bus->dev;
 174         u32 ctrl, cnt;
 175         int retval;
 176
 177
 178         if (i2c_debug && !joined)
 179                 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
 180
 181         /* Deal with i2c probe functions with zero payload */
 182         if (msg->len == 0) {
 183                 cx_write(bus->reg_addr, msg->addr << 25);
 184                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
 185                 if (!i2c_wait_done(i2c_adap))
 186                         return -EIO;
 187                 if (!i2c_slave_did_ack(i2c_adap))
 188                         return -EIO;
 189
 190
 191                 dprintk(1, "%s() returns 0\n", __func__);
 192                 return 0;
 193         }
 194
 195         if (i2c_debug) {
 196                 if (joined)
 197                         dprintk(1, " R");
 198                 else
 199                         dprintk(1, " <R %02x", (msg->addr << 1) + 1);
 200         }
 201
 202         for (cnt = 0; cnt < msg->len; cnt++) {
 203
 204                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
 205
 206                 if (cnt < msg->len - 1)
 207                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 208
 209                 cx_write(bus->reg_addr, msg->addr << 25);
 210                 cx_write(bus->reg_ctrl, ctrl);
 211
 212                 retval = i2c_wait_done(i2c_adap);
 213                 if (retval < 0)
 214                         goto err;
 215                 if (retval == 0)
 216                         goto eio;
 217                 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
 218                 if (i2c_debug) {
 219                         dprintk(1, " %02x", msg->buf[cnt]);
 220                         if (!(ctrl & I2C_NOSTOP))
 221                                 dprintk(1, " >\n");
 222                 }
 223         }
 224         return msg->len;
 225
 226  eio:
 227         retval = -EIO;
 228  err:
 229         if (i2c_debug)
 230                 printk(KERN_ERR " ERR: %d\n", retval);
 231         return retval;
 232 }
 233
 234 static int i2c_xfer(struct i2c_adapter *i2c_adap,
 235                     struct i2c_msg *msgs, int num)
 236 {
 237         struct cx23885_i2c *bus = i2c_adap->algo_data;
 238         struct cx23885_dev *dev = bus->dev;
 239         int i, retval = 0;
 240
 241         dprintk(1, "%s(num = %d)\n", __func__, num);
 242
 243         for (i = 0 ; i < num; i++) {
 244                 dprintk(1, "%s(num = %d) addr = 0x%02x  len = 0x%x\n",
 245                         __func__, num, msgs[i].addr, msgs[i].len);
 246                 if (msgs[i].flags & I2C_M_RD) {
 247                         /* read */
 248                         retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
 249                 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
 250                            msgs[i].addr == msgs[i + 1].addr) {
 251                         /* write then read from same address */
 252                         retval = i2c_sendbytes(i2c_adap, &msgs[i],
 253                                                msgs[i + 1].len);
 254                         if (retval < 0)
 255                                 goto err;
 256                         i++;
 257                         retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
 258                 } else {
 259                         /* write */
 260                         retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
 261                 }
 262                 if (retval < 0)
 263                         goto err;
 264         }
 265         return num;
 266
 267  err:
 268         return retval;
 269 }
 270
 271 static u32 cx23885_functionality(struct i2c_adapter *adap)
 272 {
 273         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
 274 }
 275
 276 static struct i2c_algorithm cx23885_i2c_algo_template = {
 277         .master_xfer    = i2c_xfer,
 278         .functionality  = cx23885_functionality,
 279 };
 280
 281 /* ----------------------------------------------------------------------- */
 282
 283 static struct i2c_adapter cx23885_i2c_adap_template = {
 284         .name              = "cx23885",
 285         .owner             = THIS_MODULE,
 286         .id                = I2C_HW_B_CX23885,
 287         .algo              = &cx23885_i2c_algo_template,
 288 };
 289
 290 static struct i2c_client cx23885_i2c_client_template = {
 291         .name   = "cx23885 internal",
 292 };
 293
 294 static char *i2c_devs[128] = {
 295         [0x10 >> 1] = "tda10048",
 296         [0x12 >> 1] = "dib7000pc",
 297         [0x1c >> 1] = "lgdt3303",
 298         [0x86 >> 1] = "tda9887",
 299         [0x32 >> 1] = "cx24227",
 300         [0x88 >> 1] = "cx25837",
 301         [0x84 >> 1] = "tda8295",
 302         [0xa0 >> 1] = "eeprom",
 303         [0xc0 >> 1] = "tuner/mt2131/tda8275",
 304         [0xc2 >> 1] = "tuner/mt2131/tda8275/xc5000/xc3028",
 305         [0xc8 >> 1] = "tuner/xc3028L",
 306 };
 307
 308 static void do_i2c_scan(char *name, struct i2c_client *c)
 309 {
 310         unsigned char buf;
 311         int i, rc;
 312
 313         for (i = 0; i < 128; i++) {
 314                 c->addr = i;
 315                 rc = i2c_master_recv(c, &buf, 0);
 316                 if (rc < 0)
 317                         continue;
 318                 printk(KERN_INFO "%s: i2c scan: found device @ 0x%x  [%s]\n",
 319                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 320         }
 321 }
 322
 323 /* init + register i2c algo-bit adapter */
 324 int cx23885_i2c_register(struct cx23885_i2c *bus)
 325 {
 326         struct cx23885_dev *dev = bus->dev;
 327
 328         dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
 329
 330         memcpy(&bus->i2c_adap, &cx23885_i2c_adap_template,
 331                sizeof(bus->i2c_adap));
 332         memcpy(&bus->i2c_algo, &cx23885_i2c_algo_template,
 333                sizeof(bus->i2c_algo));
 334         memcpy(&bus->i2c_client, &cx23885_i2c_client_template,
 335                sizeof(bus->i2c_client));
 336
 337         bus->i2c_adap.dev.parent = &dev->pci->dev;
 338
 339         strlcpy(bus->i2c_adap.name, bus->dev->name,
 340                 sizeof(bus->i2c_adap.name));
 341
 342         bus->i2c_algo.data = bus;
 343         bus->i2c_adap.algo_data = bus;
 344         i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
 345         i2c_add_adapter(&bus->i2c_adap);
 346
 347         bus->i2c_client.adapter = &bus->i2c_adap;
 348
 349         if (0 == bus->i2c_rc) {
 350                 dprintk(1, "%s: i2c bus %d registered\n", dev->name, bus->nr);
 351                 if (i2c_scan) {
 352                         printk(KERN_INFO "%s: scan bus %d:\n",
 353                                         dev->name, bus->nr);
 354                         do_i2c_scan(dev->name, &bus->i2c_client);
 355                 }
 356         } else
 357                 printk(KERN_WARNING "%s: i2c bus %d register FAILED\n",
 358                         dev->name, bus->nr);
 359
 360         return bus->i2c_rc;
 361 }
 362
 363 int cx23885_i2c_unregister(struct cx23885_i2c *bus)
 364 {
 365         i2c_del_adapter(&bus->i2c_adap);
 366         return 0;
 367 }
 368
 369 void cx23885_av_clk(struct cx23885_dev *dev, int enable)
 370 {
 371         /* write 0 to bus 2 addr 0x144 via i2x_xfer() */
 372         char buffer[3];
 373         struct i2c_msg msg;
 374         dprintk(1, "%s(enabled = %d)\n", __func__, enable);
 375
 376         /* Register 0x144 */
 377         buffer[0] = 0x01;
 378         buffer[1] = 0x44;
 379         if (enable == 1)
 380                 buffer[2] = 0x05;
 381         else
 382                 buffer[2] = 0x00;
 383
 384         msg.addr = 0x44;
 385         msg.flags = I2C_M_TEN;
 386         msg.len = 3;
 387         msg.buf = buffer;
 388
 389         i2c_xfer(&dev->i2c_bus[2].i2c_adap, &msg, 1);
 390 }
 391
 392 /* ----------------------------------------------------------------------- */
 393
 394 /*
 395  * Local variables:
 396  * c-basic-offset: 8
 397  * End:
 398  */