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/moduleparam.h>
  22 #include <linux/init.h>
  23 #include <linux/delay.h>
  24 #include <asm/io.h>
  25
  26 #include <media/v4l2-common.h>
  27
  28 static unsigned int i2c_debug;
  29 module_param(i2c_debug, int, 0644);
  30 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  31
  32 static unsigned int i2c_scan;
  33 module_param(i2c_scan, int, 0444);
  34 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
  35
  36 #define dprintk(level, fmt, arg...)\
  37         do { if (i2c_debug >= level)\
  38                 printk(KERN_DEBUG pr_fmt("%s: i2c:" fmt), \
  39                         __func__, ##arg); \
  40         } while (0)
  41
  42 #define I2C_WAIT_DELAY 32
  43 #define I2C_WAIT_RETRY 64
  44
  45 #define I2C_EXTEND  (1 << 3)
  46 #define I2C_NOSTOP  (1 << 4)
  47
  48 static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
  49 {
  50         struct cx23885_i2c *bus = i2c_adap->algo_data;
  51         struct cx23885_dev *dev = bus->dev;
  52         return cx_read(bus->reg_stat) & 0x01;
  53 }
  54
  55 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
  56 {
  57         struct cx23885_i2c *bus = i2c_adap->algo_data;
  58         struct cx23885_dev *dev = bus->dev;
  59         return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
  60 }
  61
  62 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
  63 {
  64         int count;
  65
  66         for (count = 0; count < I2C_WAIT_RETRY; count++) {
  67                 if (!i2c_is_busy(i2c_adap))
  68                         break;
  69                 udelay(I2C_WAIT_DELAY);
  70         }
  71
  72         if (I2C_WAIT_RETRY == count)
  73                 return 0;
  74
  75         return 1;
  76 }
  77
  78 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
  79                          const struct i2c_msg *msg, int joined_rlen)
  80 {
  81         struct cx23885_i2c *bus = i2c_adap->algo_data;
  82         struct cx23885_dev *dev = bus->dev;
  83         u32 wdata, addr, ctrl;
  84         int retval, cnt;
  85
  86         if (joined_rlen)
  87                 dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__,
  88                         msg->len, joined_rlen);
  89         else
  90                 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
  91
  92         /* Deal with i2c probe functions with zero payload */
  93         if (msg->len == 0) {
  94                 cx_write(bus->reg_addr, msg->addr << 25);
  95                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
  96                 if (!i2c_wait_done(i2c_adap))
  97                         return -EIO;
  98                 if (!i2c_slave_did_ack(i2c_adap))
  99                         return -ENXIO;
 100
 101                 dprintk(1, "%s() returns 0\n", __func__);
 102                 return 0;
 103         }
 104
 105
 106         /* dev, reg + first byte */
 107         addr = (msg->addr << 25) | msg->buf[0];
 108         wdata = msg->buf[0];
 109         ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 110
 111         if (msg->len > 1)
 112                 ctrl |= I2C_NOSTOP | I2C_EXTEND;
 113         else if (joined_rlen)
 114                 ctrl |= I2C_NOSTOP;
 115
 116         cx_write(bus->reg_addr, addr);
 117         cx_write(bus->reg_wdata, wdata);
 118         cx_write(bus->reg_ctrl, ctrl);
 119
 120         if (!i2c_wait_done(i2c_adap))
 121                 goto eio;
 122         if (i2c_debug) {
 123                 printk(KERN_DEBUG " <W %02x %02x", msg->addr << 1, msg->buf[0]);
 124                 if (!(ctrl & I2C_NOSTOP))
 125                         pr_cont(" >\n");
 126         }
 127
 128         for (cnt = 1; cnt < msg->len; cnt++) {
 129                 /* following bytes */
 130                 wdata = msg->buf[cnt];
 131                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 132
 133                 if (cnt < msg->len - 1)
 134                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 135                 else if (joined_rlen)
 136                         ctrl |= I2C_NOSTOP;
 137
 138                 cx_write(bus->reg_addr, addr);
 139                 cx_write(bus->reg_wdata, wdata);
 140                 cx_write(bus->reg_ctrl, ctrl);
 141
 142                 if (!i2c_wait_done(i2c_adap))
 143                         goto eio;
 144                 if (i2c_debug) {
 145                         pr_cont(" %02x", msg->buf[cnt]);
 146                         if (!(ctrl & I2C_NOSTOP))
 147                                 pr_cont(" >\n");
 148                 }
 149         }
 150         return msg->len;
 151
 152  eio:
 153         retval = -EIO;
 154         if (i2c_debug)
 155                 pr_err(" ERR: %d\n", retval);
 156         return retval;
 157 }
 158
 159 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
 160                          const struct i2c_msg *msg, int joined)
 161 {
 162         struct cx23885_i2c *bus = i2c_adap->algo_data;
 163         struct cx23885_dev *dev = bus->dev;
 164         u32 ctrl, cnt;
 165         int retval;
 166
 167
 168         if (i2c_debug && !joined)
 169                 dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
 170
 171         /* Deal with i2c probe functions with zero payload */
 172         if (msg->len == 0) {
 173                 cx_write(bus->reg_addr, msg->addr << 25);
 174                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
 175                 if (!i2c_wait_done(i2c_adap))
 176                         return -EIO;
 177                 if (!i2c_slave_did_ack(i2c_adap))
 178                         return -ENXIO;
 179
 180
 181                 dprintk(1, "%s() returns 0\n", __func__);
 182                 return 0;
 183         }
 184
 185         if (i2c_debug) {
 186                 if (joined)
 187                         dprintk(1, " R");
 188                 else
 189                         dprintk(1, " <R %02x", (msg->addr << 1) + 1);
 190         }
 191
 192         for (cnt = 0; cnt < msg->len; cnt++) {
 193
 194                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
 195
 196                 if (cnt < msg->len - 1)
 197                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 198
 199                 cx_write(bus->reg_addr, msg->addr << 25);
 200                 cx_write(bus->reg_ctrl, ctrl);
 201
 202                 if (!i2c_wait_done(i2c_adap))
 203                         goto eio;
 204                 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
 205                 if (i2c_debug) {
 206                         dprintk(1, " %02x", msg->buf[cnt]);
 207                         if (!(ctrl & I2C_NOSTOP))
 208                                 dprintk(1, " >\n");
 209                 }
 210         }
 211         return msg->len;
 212
 213  eio:
 214         retval = -EIO;
 215         if (i2c_debug)
 216                 pr_err(" ERR: %d\n", retval);
 217         return retval;
 218 }
 219
 220 static int i2c_xfer(struct i2c_adapter *i2c_adap,
 221                     struct i2c_msg *msgs, int num)
 222 {
 223         int i, retval = 0;
 224
 225         dprintk(1, "%s(num = %d)\n", __func__, num);
 226
 227         for (i = 0 ; i < num; i++) {
 228                 dprintk(1, "%s(num = %d) addr = 0x%02x  len = 0x%x\n",
 229                         __func__, num, msgs[i].addr, msgs[i].len);
 230                 if (msgs[i].flags & I2C_M_RD) {
 231                         /* read */
 232                         retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
 233                 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
 234                            msgs[i].addr == msgs[i + 1].addr) {
 235                         /* write then read from same address */
 236                         retval = i2c_sendbytes(i2c_adap, &msgs[i],
 237                                                msgs[i + 1].len);
 238                         if (retval < 0)
 239                                 goto err;
 240                         i++;
 241                         retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
 242                 } else {
 243                         /* write */
 244                         retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
 245                 }
 246                 if (retval < 0)
 247                         goto err;
 248         }
 249         return num;
 250
 251  err:
 252         return retval;
 253 }
 254
 255 static u32 cx23885_functionality(struct i2c_adapter *adap)
 256 {
 257         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
 258 }
 259
 260 static const struct i2c_algorithm cx23885_i2c_algo_template = {
 261         .master_xfer    = i2c_xfer,
 262         .functionality  = cx23885_functionality,
 263 };
 264
 265 /* ----------------------------------------------------------------------- */
 266
 267 static const struct i2c_adapter cx23885_i2c_adap_template = {
 268         .name              = "cx23885",
 269         .owner             = THIS_MODULE,
 270         .algo              = &cx23885_i2c_algo_template,
 271 };
 272
 273 static const struct i2c_client cx23885_i2c_client_template = {
 274         .name   = "cx23885 internal",
 275 };
 276
 277 static char *i2c_devs[128] = {
 278         [0x10 >> 1] = "tda10048",
 279         [0x12 >> 1] = "dib7000pc",
 280         [0x1c >> 1] = "lgdt3303",
 281         [0x80 >> 1] = "cs3308",
 282         [0x82 >> 1] = "cs3308",
 283         [0x86 >> 1] = "tda9887",
 284         [0x32 >> 1] = "cx24227",
 285         [0x88 >> 1] = "cx25837",
 286         [0x84 >> 1] = "tda8295",
 287         [0x98 >> 1] = "flatiron",
 288         [0xa0 >> 1] = "eeprom",
 289         [0xc0 >> 1] = "tuner/mt2131/tda8275",
 290         [0xc2 >> 1] = "tuner/mt2131/tda8275/xc5000/xc3028",
 291         [0xc8 >> 1] = "tuner/xc3028L",
 292 };
 293
 294 static void do_i2c_scan(char *name, struct i2c_client *c)
 295 {
 296         unsigned char buf;
 297         int i, rc;
 298
 299         for (i = 0; i < 128; i++) {
 300                 c->addr = i;
 301                 rc = i2c_master_recv(c, &buf, 0);
 302                 if (rc < 0)
 303                         continue;
 304                 pr_info("%s: i2c scan: found device @ 0x%04x  [%s]\n",
 305                        name, i, i2c_devs[i] ? i2c_devs[i] : "???");
 306         }
 307 }
 308
 309 /* init + register i2c adapter */
 310 int cx23885_i2c_register(struct cx23885_i2c *bus)
 311 {
 312         struct cx23885_dev *dev = bus->dev;
 313
 314         dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
 315
 316         bus->i2c_adap = cx23885_i2c_adap_template;
 317         bus->i2c_client = cx23885_i2c_client_template;
 318         bus->i2c_adap.dev.parent = &dev->pci->dev;
 319
 320         strlcpy(bus->i2c_adap.name, bus->dev->name,
 321                 sizeof(bus->i2c_adap.name));
 322
 323         bus->i2c_adap.algo_data = bus;
 324         i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
 325         i2c_add_adapter(&bus->i2c_adap);
 326
 327         bus->i2c_client.adapter = &bus->i2c_adap;
 328
 329         if (0 == bus->i2c_rc) {
 330                 dprintk(1, "%s: i2c bus %d registered\n", dev->name, bus->nr);
 331                 if (i2c_scan) {
 332                         pr_info("%s: scan bus %d:\n",
 333                                         dev->name, bus->nr);
 334                         do_i2c_scan(dev->name, &bus->i2c_client);
 335                 }
 336         } else
 337                 pr_warn("%s: i2c bus %d register FAILED\n",
 338                         dev->name, bus->nr);
 339
 340         /* Instantiate the IR receiver device, if present */
 341         if (0 == bus->i2c_rc) {
 342                 struct i2c_board_info info;
 343                 const unsigned short addr_list[] = {
 344                         0x6b, I2C_CLIENT_END
 345                 };
 346
 347                 memset(&info, 0, sizeof(struct i2c_board_info));
 348                 strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
 349                 /* Use quick read command for probe, some IR chips don't
 350                  * support writes */
 351                 i2c_new_probed_device(&bus->i2c_adap, &info, addr_list,
 352                                       i2c_probe_func_quick_read);
 353         }
 354
 355         return bus->i2c_rc;
 356 }
 357
 358 int cx23885_i2c_unregister(struct cx23885_i2c *bus)
 359 {
 360         i2c_del_adapter(&bus->i2c_adap);
 361         return 0;
 362 }
 363
 364 void cx23885_av_clk(struct cx23885_dev *dev, int enable)
 365 {
 366         /* write 0 to bus 2 addr 0x144 via i2x_xfer() */
 367         char buffer[3];
 368         struct i2c_msg msg;
 369         dprintk(1, "%s(enabled = %d)\n", __func__, enable);
 370
 371         /* Register 0x144 */
 372         buffer[0] = 0x01;
 373         buffer[1] = 0x44;
 374         if (enable == 1)
 375                 buffer[2] = 0x05;
 376         else
 377                 buffer[2] = 0x00;
 378
 379         msg.addr = 0x44;
 380         msg.flags = I2C_M_TEN;
 381         msg.len = 3;
 382         msg.buf = buffer;
 383
 384         i2c_xfer(&dev->i2c_bus[2].i2c_adap, &msg, 1);
 385 }