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 -ENXIO;
 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         if (!i2c_wait_done(i2c_adap))
 124                 goto eio;
 125         if (!i2c_slave_did_ack(i2c_adap)) {
 126                 retval = -ENXIO;
 127                 goto err;
 128         }
 129         if (i2c_debug) {
 130                 printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 131                 if (!(ctrl & I2C_NOSTOP))
 132                         printk(" >\n");
 133         }
 134
 135         for (cnt = 1; cnt < msg->len; cnt++) {
 136                 /* following bytes */
 137                 wdata = msg->buf[cnt];
 138                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 139
 140                 if (cnt < msg->len - 1)
 141                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 142                 else if (joined_rlen)
 143                         ctrl |= I2C_NOSTOP;
 144
 145                 cx_write(bus->reg_addr, addr);
 146                 cx_write(bus->reg_wdata, wdata);
 147                 cx_write(bus->reg_ctrl, ctrl);
 148
 149                 if (!i2c_wait_done(i2c_adap))
 150                         goto eio;
 151                 if (i2c_debug) {
 152                         dprintk(1, " %02x", msg->buf[cnt]);
 153                         if (!(ctrl & I2C_NOSTOP))
 154                                 dprintk(1, " >\n");
 155                 }
 156         }
 157         return msg->len;
 158
 159  eio:
 160         retval = -EIO;
 161  err:
 162         if (i2c_debug)
 163                 printk(KERN_ERR " ERR: %d\n", retval);
 164         return retval;
 165 }
 166
 167 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
 168                          const struct i2c_msg *msg, int joined)
 169 {
 170         struct cx23885_i2c *bus = i2c_adap->algo_data;
 171         struct cx23885_dev *dev = bus->dev;
 172         u32 ctrl, cnt;
 173         int retval;
 174
 175
 176         if (i2c_debug && !joined)
 177                 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
 178
 179         /* Deal with i2c probe functions with zero payload */
 180         if (msg->len == 0) {
 181                 cx_write(bus->reg_addr, msg->addr << 25);
 182                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
 183                 if (!i2c_wait_done(i2c_adap))
 184                         return -EIO;
 185                 if (!i2c_slave_did_ack(i2c_adap))
 186                         return -ENXIO;
 187
 188
 189                 dprintk(1, "%s() returns 0\n", __func__);
 190                 return 0;
 191         }
 192
 193         if (i2c_debug) {
 194                 if (joined)
 195                         dprintk(1, " R");
 196                 else
 197                         dprintk(1, " <R %02x", (msg->addr << 1) + 1);
 198         }
 199
 200         for (cnt = 0; cnt < msg->len; cnt++) {
 201
 202                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
 203
 204                 if (cnt < msg->len - 1)
 205                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 206
 207                 cx_write(bus->reg_addr, msg->addr << 25);
 208                 cx_write(bus->reg_ctrl, ctrl);
 209
 210                 if (!i2c_wait_done(i2c_adap))
 211                         goto eio;
 212                 if (cnt == 0 && !i2c_slave_did_ack(i2c_adap)) {
 213                         retval = -ENXIO;
 214                         goto err;
 215                 }
 216                 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
 217                 if (i2c_debug) {
 218                         dprintk(1, " %02x", msg->buf[cnt]);
 219                         if (!(ctrl & I2C_NOSTOP))
 220                                 dprintk(1, " >\n");
 221                 }
 222         }
 223         return msg->len;
 224
 225  eio:
 226         retval = -EIO;
 227  err:
 228         if (i2c_debug)
 229                 printk(KERN_ERR " ERR: %d\n", retval);
 230         return retval;
 231 }
 232
 233 static int i2c_xfer(struct i2c_adapter *i2c_adap,
 234                     struct i2c_msg *msgs, int num)
 235 {
 236         struct cx23885_i2c *bus = i2c_adap->algo_data;
 237         struct cx23885_dev *dev = bus->dev;
 238         int i, retval = 0;
 239
 240         dprintk(1, "%s(num = %d)\n", __func__, num);
 241
 242         for (i = 0 ; i < num; i++) {
 243                 dprintk(1, "%s(num = %d) addr = 0x%02x  len = 0x%x\n",
 244                         __func__, num, msgs[i].addr, msgs[i].len);
 245                 if (msgs[i].flags & I2C_M_RD) {
 246                         /* read */
 247                         retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
 248                 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
 249                            msgs[i].addr == msgs[i + 1].addr) {
 250                         /* write then read from same address */
 251                         retval = i2c_sendbytes(i2c_adap, &msgs[i],
 252                                                msgs[i + 1].len);
 253                         if (retval < 0)
 254                                 goto err;
 255                         i++;
 256                         retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
 257                 } else {
 258                         /* write */
 259                         retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
 260                 }
 261                 if (retval < 0)
 262                         goto err;
 263         }
 264         return num;
 265
 266  err:
 267         return retval;
 268 }
 269
 270 static u32 cx23885_functionality(struct i2c_adapter *adap)
 271 {
 272         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
 273 }
 274
 275 static struct i2c_algorithm cx23885_i2c_algo_template = {
 276         .master_xfer    = i2c_xfer,
 277         .functionality  = cx23885_functionality,
 278 };
 279
 280 /* ----------------------------------------------------------------------- */
 281
 282 static struct i2c_adapter cx23885_i2c_adap_template = {
 283         .name              = "cx23885",
 284         .owner             = THIS_MODULE,
 285         .algo              = &cx23885_i2c_algo_template,
 286 };
 287
 288 static struct i2c_client cx23885_i2c_client_template = {
 289         .name   = "cx23885 internal",
 290 };
 291
 292 static char *i2c_devs[128] = {
 293         [0x10 >> 1] = "tda10048",
 294         [0x12 >> 1] = "dib7000pc",
 295         [0x1c >> 1] = "lgdt3303",
 296         [0x86 >> 1] = "tda9887",
 297         [0x32 >> 1] = "cx24227",
 298         [0x88 >> 1] = "cx25837",
 299         [0x84 >> 1] = "tda8295",
 300         [0xa0 >> 1] = "eeprom",
 301         [0xc0 >> 1] = "tuner/mt2131/tda8275",
 302         [0xc2 >> 1] = "tuner/mt2131/tda8275/xc5000/xc3028",
 303         [0xc8 >> 1] = "tuner/xc3028L",
 304 };
 305
 306 static void do_i2c_scan(char *name, struct i2c_client *c)
 307 {
 308         unsigned char buf;
 309         int i, rc;
 310
 311         for (i = 0; i < 128; i++) {
 312                 c->addr = i;
 313                 rc = i2c_master_recv(c, &buf, 0);
 314                 if (rc < 0)
 315                         continue;
 316                 printk(KERN_INFO "%s: i2c scan: found device @ 0x%x  [%s]\n",
 317                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 318         }
 319 }
 320
 321 /* init + register i2c algo-bit adapter */
 322 int cx23885_i2c_register(struct cx23885_i2c *bus)
 323 {
 324         struct cx23885_dev *dev = bus->dev;
 325
 326         dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
 327
 328         memcpy(&bus->i2c_adap, &cx23885_i2c_adap_template,
 329                sizeof(bus->i2c_adap));
 330         memcpy(&bus->i2c_algo, &cx23885_i2c_algo_template,
 331                sizeof(bus->i2c_algo));
 332         memcpy(&bus->i2c_client, &cx23885_i2c_client_template,
 333                sizeof(bus->i2c_client));
 334
 335         bus->i2c_adap.dev.parent = &dev->pci->dev;
 336
 337         strlcpy(bus->i2c_adap.name, bus->dev->name,
 338                 sizeof(bus->i2c_adap.name));
 339
 340         bus->i2c_algo.data = bus;
 341         bus->i2c_adap.algo_data = bus;
 342         i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
 343         i2c_add_adapter(&bus->i2c_adap);
 344
 345         bus->i2c_client.adapter = &bus->i2c_adap;
 346
 347         if (0 == bus->i2c_rc) {
 348                 dprintk(1, "%s: i2c bus %d registered\n", dev->name, bus->nr);
 349                 if (i2c_scan) {
 350                         printk(KERN_INFO "%s: scan bus %d:\n",
 351                                         dev->name, bus->nr);
 352                         do_i2c_scan(dev->name, &bus->i2c_client);
 353                 }
 354         } else
 355                 printk(KERN_WARNING "%s: i2c bus %d register FAILED\n",
 356                         dev->name, bus->nr);
 357
 358         /* Instantiate the IR receiver device, if present */
 359         if (0 == bus->i2c_rc) {
 360                 struct i2c_board_info info;
 361                 const unsigned short addr_list[] = {
 362                         0x6b, I2C_CLIENT_END
 363                 };
 364
 365                 memset(&info, 0, sizeof(struct i2c_board_info));
 366                 strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
 367                 /* Use quick read command for probe, some IR chips don't
 368                  * support writes */
 369                 i2c_new_probed_device(&bus->i2c_adap, &info, addr_list,
 370                                       i2c_probe_func_quick_read);
 371         }
 372
 373         return bus->i2c_rc;
 374 }
 375
 376 int cx23885_i2c_unregister(struct cx23885_i2c *bus)
 377 {
 378         i2c_del_adapter(&bus->i2c_adap);
 379         return 0;
 380 }
 381
 382 void cx23885_av_clk(struct cx23885_dev *dev, int enable)
 383 {
 384         /* write 0 to bus 2 addr 0x144 via i2x_xfer() */
 385         char buffer[3];
 386         struct i2c_msg msg;
 387         dprintk(1, "%s(enabled = %d)\n", __func__, enable);
 388
 389         /* Register 0x144 */
 390         buffer[0] = 0x01;
 391         buffer[1] = 0x44;
 392         if (enable == 1)
 393                 buffer[2] = 0x05;
 394         else
 395                 buffer[2] = 0x00;
 396
 397         msg.addr = 0x44;
 398         msg.flags = I2C_M_TEN;
 399         msg.len = 3;
 400         msg.buf = buffer;
 401
 402         i2c_xfer(&dev->i2c_bus[2].i2c_adap, &msg, 1);
 403 }
 404
 405 /* ----------------------------------------------------------------------- */
 406
 407 /*
 408  * Local variables:
 409  * c-basic-offset: 8
 410  * End:
 411  */