drivers/media/pci/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
  18 #include "cx23885.h"
  19
  20 #include <linux/module.h>
  21 #include <linux/init.h>
  22 #include <linux/delay.h>
  23 #include <asm/io.h>
  24
  25 #include <media/v4l2-common.h>
  26
  27 static unsigned int i2c_debug;
  28 module_param(i2c_debug, int, 0644);
  29 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  30
  31 static unsigned int i2c_scan;
  32 module_param(i2c_scan, int, 0444);
  33 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
  34
  35 #define dprintk(level, fmt, arg...)\
  36         do { if (i2c_debug >= level)\
  37                 printk(KERN_DEBUG pr_fmt("%s: i2c:" fmt), \
  38                         __func__, ##arg); \
  39         } while (0)
  40
  41 #define I2C_WAIT_DELAY 32
  42 #define I2C_WAIT_RETRY 64
  43
  44 #define I2C_EXTEND  (1 << 3)
  45 #define I2C_NOSTOP  (1 << 4)
  46
  47 static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
  48 {
  49         struct cx23885_i2c *bus = i2c_adap->algo_data;
  50         struct cx23885_dev *dev = bus->dev;
  51         return cx_read(bus->reg_stat) & 0x01;
  52 }
  53
  54 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
  55 {
  56         struct cx23885_i2c *bus = i2c_adap->algo_data;
  57         struct cx23885_dev *dev = bus->dev;
  58         return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
  59 }
  60
  61 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
  62 {
  63         int count;
  64
  65         for (count = 0; count < I2C_WAIT_RETRY; count++) {
  66                 if (!i2c_is_busy(i2c_adap))
  67                         break;
  68                 udelay(I2C_WAIT_DELAY);
  69         }
  70
  71         if (I2C_WAIT_RETRY == count)
  72                 return 0;
  73
  74         return 1;
  75 }
  76
  77 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
  78                          const struct i2c_msg *msg, int joined_rlen)
  79 {
  80         struct cx23885_i2c *bus = i2c_adap->algo_data;
  81         struct cx23885_dev *dev = bus->dev;
  82         u32 wdata, addr, ctrl;
  83         int retval, cnt;
  84
  85         if (joined_rlen)
  86                 dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__,
  87                         msg->len, joined_rlen);
  88         else
  89                 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
  90
  91         /* Deal with i2c probe functions with zero payload */
  92         if (msg->len == 0) {
  93                 cx_write(bus->reg_addr, msg->addr << 25);
  94                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
  95                 if (!i2c_wait_done(i2c_adap))
  96                         return -EIO;
  97                 if (!i2c_slave_did_ack(i2c_adap))
  98                         return -ENXIO;
  99
 100                 dprintk(1, "%s() returns 0\n", __func__);
 101                 return 0;
 102         }
 103
 104
 105         /* dev, reg + first byte */
 106         addr = (msg->addr << 25) | msg->buf[0];
 107         wdata = msg->buf[0];
 108         ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 109
 110         if (msg->len > 1)
 111                 ctrl |= I2C_NOSTOP | I2C_EXTEND;
 112         else if (joined_rlen)
 113                 ctrl |= I2C_NOSTOP;
 114
 115         cx_write(bus->reg_addr, addr);
 116         cx_write(bus->reg_wdata, wdata);
 117         cx_write(bus->reg_ctrl, ctrl);
 118
 119         if (!i2c_wait_done(i2c_adap))
 120                 goto eio;
 121         if (i2c_debug) {
 122                 printk(KERN_DEBUG " <W %02x %02x", msg->addr << 1, msg->buf[0]);
 123                 if (!(ctrl & I2C_NOSTOP))
 124                         pr_cont(" >\n");
 125         }
 126
 127         for (cnt = 1; cnt < msg->len; cnt++) {
 128                 /* following bytes */
 129                 wdata = msg->buf[cnt];
 130                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 131
 132                 if (cnt < msg->len - 1)
 133                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 134                 else if (joined_rlen)
 135                         ctrl |= I2C_NOSTOP;
 136
 137                 cx_write(bus->reg_addr, addr);
 138                 cx_write(bus->reg_wdata, wdata);
 139                 cx_write(bus->reg_ctrl, ctrl);
 140
 141                 if (!i2c_wait_done(i2c_adap))
 142                         goto eio;
 143                 if (i2c_debug) {
 144                         pr_cont(" %02x", msg->buf[cnt]);
 145                         if (!(ctrl & I2C_NOSTOP))
 146                                 pr_cont(" >\n");
 147                 }
 148         }
 149         return msg->len;
 150
 151  eio:
 152         retval = -EIO;
 153         if (i2c_debug)
 154                 pr_err(" ERR: %d\n", retval);
 155         return retval;
 156 }
 157
 158 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
 159                          const struct i2c_msg *msg, int joined)
 160 {
 161         struct cx23885_i2c *bus = i2c_adap->algo_data;
 162         struct cx23885_dev *dev = bus->dev;
 163         u32 ctrl, cnt;
 164         int retval;
 165
 166
 167         if (i2c_debug && !joined)
 168                 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
 169
 170         /* Deal with i2c probe functions with zero payload */
 171         if (msg->len == 0) {
 172                 cx_write(bus->reg_addr, msg->addr << 25);
 173                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
 174                 if (!i2c_wait_done(i2c_adap))
 175                         return -EIO;
 176                 if (!i2c_slave_did_ack(i2c_adap))
 177                         return -ENXIO;
 178
 179
 180                 dprintk(1, "%s() returns 0\n", __func__);
 181                 return 0;
 182         }
 183
 184         if (i2c_debug) {
 185                 if (joined)
 186                         dprintk(1, " R");
 187                 else
 188                         dprintk(1, " <R %02x", (msg->addr << 1) + 1);
 189         }
 190
 191         for (cnt = 0; cnt < msg->len; cnt++) {
 192
 193                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
 194
 195                 if (cnt < msg->len - 1)
 196                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 197
 198                 cx_write(bus->reg_addr, msg->addr << 25);
 199                 cx_write(bus->reg_ctrl, ctrl);
 200
 201                 if (!i2c_wait_done(i2c_adap))
 202                         goto eio;
 203                 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
 204                 if (i2c_debug) {
 205                         dprintk(1, " %02x", msg->buf[cnt]);
 206                         if (!(ctrl & I2C_NOSTOP))
 207                                 dprintk(1, " >\n");
 208                 }
 209         }
 210         return msg->len;
 211
 212  eio:
 213         retval = -EIO;
 214         if (i2c_debug)
 215                 pr_err(" ERR: %d\n", retval);
 216         return retval;
 217 }
 218
 219 static int i2c_xfer(struct i2c_adapter *i2c_adap,
 220                     struct i2c_msg *msgs, int num)
 221 {
 222         int i, retval = 0;
 223
 224         dprintk(1, "%s(num = %d)\n", __func__, num);
 225
 226         for (i = 0 ; i < num; i++) {
 227                 dprintk(1, "%s(num = %d) addr = 0x%02x  len = 0x%x\n",
 228                         __func__, num, msgs[i].addr, msgs[i].len);
 229                 if (msgs[i].flags & I2C_M_RD) {
 230                         /* read */
 231                         retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
 232                 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
 233                            msgs[i].addr == msgs[i + 1].addr) {
 234                         /* write then read from same address */
 235                         retval = i2c_sendbytes(i2c_adap, &msgs[i],
 236                                                msgs[i + 1].len);
 237                         if (retval < 0)
 238                                 goto err;
 239                         i++;
 240                         retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
 241                 } else {
 242                         /* write */
 243                         retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
 244                 }
 245                 if (retval < 0)
 246                         goto err;
 247         }
 248         return num;
 249
 250  err:
 251         return retval;
 252 }
 253
 254 static u32 cx23885_functionality(struct i2c_adapter *adap)
 255 {
 256         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
 257 }
 258
 259 static const struct i2c_algorithm cx23885_i2c_algo_template = {
 260         .master_xfer    = i2c_xfer,
 261         .functionality  = cx23885_functionality,
 262 };
 263
 264 /* ----------------------------------------------------------------------- */
 265
 266 static const struct i2c_adapter cx23885_i2c_adap_template = {
 267         .name              = "cx23885",
 268         .owner             = THIS_MODULE,
 269         .algo              = &cx23885_i2c_algo_template,
 270 };
 271
 272 static const struct i2c_client cx23885_i2c_client_template = {
 273         .name   = "cx23885 internal",
 274 };
 275
 276 static char *i2c_devs[128] = {
 277         [0x10 >> 1] = "tda10048",
 278         [0x12 >> 1] = "dib7000pc",
 279         [0x1c >> 1] = "lgdt3303",
 280         [0x80 >> 1] = "cs3308",
 281         [0x82 >> 1] = "cs3308",
 282         [0x86 >> 1] = "tda9887",
 283         [0x32 >> 1] = "cx24227",
 284         [0x88 >> 1] = "cx25837",
 285         [0x84 >> 1] = "tda8295",
 286         [0x98 >> 1] = "flatiron",
 287         [0xa0 >> 1] = "eeprom",
 288         [0xc0 >> 1] = "tuner/mt2131/tda8275",
 289         [0xc2 >> 1] = "tuner/mt2131/tda8275/xc5000/xc3028",
 290         [0xc8 >> 1] = "tuner/xc3028L",
 291 };
 292
 293 static void do_i2c_scan(char *name, struct i2c_client *c)
 294 {
 295         unsigned char buf;
 296         int i, rc;
 297
 298         for (i = 0; i < 128; i++) {
 299                 c->addr = i;
 300                 rc = i2c_master_recv(c, &buf, 0);
 301                 if (rc < 0)
 302                         continue;
 303                 pr_info("%s: i2c scan: found device @ 0x%04x  [%s]\n",
 304                        name, i, i2c_devs[i] ? i2c_devs[i] : "???");
 305         }
 306 }
 307
 308 /* init + register i2c adapter */
 309 int cx23885_i2c_register(struct cx23885_i2c *bus)
 310 {
 311         struct cx23885_dev *dev = bus->dev;
 312
 313         dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
 314
 315         bus->i2c_adap = cx23885_i2c_adap_template;
 316         bus->i2c_client = cx23885_i2c_client_template;
 317         bus->i2c_adap.dev.parent = &dev->pci->dev;
 318
 319         strscpy(bus->i2c_adap.name, bus->dev->name,
 320                 sizeof(bus->i2c_adap.name));
 321
 322         bus->i2c_adap.algo_data = bus;
 323         i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
 324         i2c_add_adapter(&bus->i2c_adap);
 325
 326         bus->i2c_client.adapter = &bus->i2c_adap;
 327
 328         if (0 == bus->i2c_rc) {
 329                 dprintk(1, "%s: i2c bus %d registered\n", dev->name, bus->nr);
 330                 if (i2c_scan) {
 331                         pr_info("%s: scan bus %d:\n",
 332                                         dev->name, bus->nr);
 333                         do_i2c_scan(dev->name, &bus->i2c_client);
 334                 }
 335         } else
 336                 pr_warn("%s: i2c bus %d register FAILED\n",
 337                         dev->name, bus->nr);
 338
 339         /* Instantiate the IR receiver device, if present */
 340         if (0 == bus->i2c_rc) {
 341                 struct i2c_board_info info;
 342                 static const unsigned short addr_list[] = {
 343                         0x6b, I2C_CLIENT_END
 344                 };
 345
 346                 memset(&info, 0, sizeof(struct i2c_board_info));
 347                 strscpy(info.type, "ir_video", I2C_NAME_SIZE);
 348                 /* Use quick read command for probe, some IR chips don't
 349                  * support writes */
 350                 i2c_new_probed_device(&bus->i2c_adap, &info, addr_list,
 351                                       i2c_probe_func_quick_read);
 352         }
 353
 354         return bus->i2c_rc;
 355 }
 356
 357 int cx23885_i2c_unregister(struct cx23885_i2c *bus)
 358 {
 359         i2c_del_adapter(&bus->i2c_adap);
 360         return 0;
 361 }
 362
 363 void cx23885_av_clk(struct cx23885_dev *dev, int enable)
 364 {
 365         /* write 0 to bus 2 addr 0x144 via i2x_xfer() */
 366         char buffer[3];
 367         struct i2c_msg msg;
 368         dprintk(1, "%s(enabled = %d)\n", __func__, enable);
 369
 370         /* Register 0x144 */
 371         buffer[0] = 0x01;
 372         buffer[1] = 0x44;
 373         if (enable == 1)
 374                 buffer[2] = 0x05;
 375         else
 376                 buffer[2] = 0x00;
 377
 378         msg.addr = 0x44;
 379         msg.flags = I2C_M_TEN;
 380         msg.len = 3;
 381         msg.buf = buffer;
 382
 383         i2c_xfer(&dev->i2c_bus[2].i2c_adap, &msg, 1);
 384 }