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