err.no Git - linux-2.6/blob - drivers/media/video/cx23885/cx23885-i2c.c

   1 /*
   2  *  Driver for the Conexant CX23885 PCIe bridge
   3  *
   4  *  Copyright (c) 2006 Steven Toth <stoth@hauppauge.com>
   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 = 2;
  33 module_param(i2c_debug, int, 0644);
  34 MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]");
  35
  36 static unsigned int i2c_scan = 0;
  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...)      if (i2c_debug >= level) \
  41         printk(KERN_DEBUG "%s: " fmt, dev->name , ## arg)
  42
  43 #define I2C_WAIT_DELAY 32
  44 #define I2C_WAIT_RETRY 64
  45
  46 #define I2C_EXTEND  (1 << 3)
  47 #define I2C_NOSTOP  (1 << 4)
  48
  49 static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
  50 {
  51         struct cx23885_i2c *bus = i2c_adap->algo_data;
  52         struct cx23885_dev *dev = bus->dev;
  53         return cx_read(bus->reg_stat) & 0x01;
  54 }
  55
  56 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
  57 {
  58         struct cx23885_i2c *bus = i2c_adap->algo_data;
  59         struct cx23885_dev *dev = bus->dev;
  60         return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
  61 }
  62
  63 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
  64 {
  65         int count;
  66
  67         for (count = 0; count < I2C_WAIT_RETRY; count++) {
  68                 if (!i2c_is_busy(i2c_adap))
  69                         break;
  70                 udelay(I2C_WAIT_DELAY);
  71         }
  72
  73         if (I2C_WAIT_RETRY == count)
  74                 return 0;
  75
  76         return 1;
  77 }
  78
  79 static int i2c_sendbytes(struct i2c_adapter *i2c_adap, const struct i2c_msg *msg, int last)
  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         dprintk(1, "%s()\n", __FUNCTION__);
  87         /* Deal with i2c probe functions with zero payload */
  88         if (msg->len == 0) {
  89                 cx_write(bus->reg_addr, msg->addr << 25);
  90                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
  91                 if (!i2c_wait_done(i2c_adap))
  92                         return -EIO;
  93                 if (!i2c_slave_did_ack(i2c_adap))
  94                         return -EIO;
  95
  96                 dprintk(1, "%s() returns 0\n", __FUNCTION__);
  97                 return 0;
  98         }
  99
 100
 101         /* dev, reg + first byte */
 102         addr = (msg->addr << 25) | msg->buf[0];
 103         wdata = msg->buf[0];
 104         ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 105
 106         if (msg->len > 1)
 107                 ctrl |= I2C_NOSTOP | I2C_EXTEND;
 108
 109         cx_write(bus->reg_addr, addr);
 110         cx_write(bus->reg_wdata, wdata);
 111         cx_write(bus->reg_ctrl, ctrl);
 112
 113         retval = i2c_wait_done(i2c_adap);
 114         if (retval < 0)
 115                 goto err;
 116         if (retval == 0)
 117                 goto eio;
 118         if (i2c_debug) {
 119                 printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 120                 if (!(ctrl & I2C_NOSTOP))
 121                         printk(" >\n");
 122         }
 123
 124         for (cnt = 1; cnt < msg->len; cnt++ ) {
 125                 /* following bytes */
 126                 wdata = msg->buf[cnt];
 127                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
 128
 129                 if (cnt < msg->len-1 || !last)
 130                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 131
 132                 //printk("addr = 0x%08x  wdata = 0x%08x  ctrl = 0x%08x\n", addr, wdata, ctrl);
 133                 cx_write(bus->reg_addr, addr);
 134                 cx_write(bus->reg_wdata, wdata);
 135                 cx_write(bus->reg_ctrl, ctrl);
 136
 137                 retval = i2c_wait_done(i2c_adap);
 138                 if (retval < 0)
 139                         goto err;
 140                 if (retval == 0)
 141                         goto eio;
 142                 if (i2c_debug) {
 143                         printk(" %02x", msg->buf[cnt]);
 144                         if (!(ctrl & I2C_NOSTOP))
 145                                 printk(" >\n");
 146                 }
 147         }
 148         return msg->len;
 149
 150  eio:
 151         retval = -EIO;
 152  err:
 153         printk(" ERR: %d\n",retval);
 154         return retval;
 155 }
 156
 157 static int i2c_readbytes(struct i2c_adapter *i2c_adap, const struct i2c_msg *msg, int last)
 158 {
 159         struct cx23885_i2c *bus = i2c_adap->algo_data;
 160         struct cx23885_dev *dev = bus->dev;
 161         u32 ctrl, cnt;
 162         int retval;
 163
 164         dprintk(1, "%s()\n", __FUNCTION__);
 165
 166         /* Deal with i2c probe functions with zero payload */
 167         if (msg->len == 0) {
 168                 cx_write(bus->reg_addr, msg->addr << 25);
 169                 cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
 170                 if (!i2c_wait_done(i2c_adap))
 171                         return -EIO;
 172                 if (!i2c_slave_did_ack(i2c_adap))
 173                         return -EIO;
 174
 175
 176                 dprintk(1, "%s() returns 0\n", __FUNCTION__);
 177                 return 0;
 178         }
 179
 180         for(cnt = 0; cnt < msg->len; cnt++) {
 181
 182                 ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
 183
 184                 if (cnt < msg->len-1 || !last)
 185                         ctrl |= I2C_NOSTOP | I2C_EXTEND;
 186
 187                 cx_write(bus->reg_addr, msg->addr << 25);
 188                 cx_write(bus->reg_ctrl, ctrl);
 189
 190                 retval = i2c_wait_done(i2c_adap);
 191                 if (retval < 0)
 192                         goto err;
 193                 if (retval == 0)
 194                         goto eio;
 195                 msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
 196                 if (i2c_debug) {
 197                         if (!(ctrl & I2C_NOSTOP))
 198                                 printk(" <R %02x", (msg->addr << 1) +1);
 199                         printk(" =%02x", msg->buf[cnt]);
 200                         if (!(ctrl & I2C_NOSTOP))
 201                                 printk(" >\n");
 202                 }
 203         }
 204         return msg->len;
 205
 206  eio:
 207         retval = -EIO;
 208  err:
 209         printk(" ERR: %d\n",retval);
 210         return retval;
 211 }
 212
 213 static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
 214 {
 215         struct cx23885_i2c *bus = i2c_adap->algo_data;
 216         struct cx23885_dev *dev = bus->dev;
 217         int i, retval = 0;
 218
 219         dprintk(1, "%s(num = %d)\n", __FUNCTION__, num);
 220
 221         for (i = 0 ; i < num; i++) {
 222                 dprintk(1, "%s(num = %d) addr = 0x%02x  len = 0x%x\n"
 223                         , __FUNCTION__, num, msgs[i].addr, msgs[i].len);
 224                 if (msgs[i].flags & I2C_M_RD) {
 225                         /* read */
 226                         retval = i2c_readbytes(i2c_adap, &msgs[i], i+1 == num);
 227                         if (retval < 0)
 228                                 goto err;
 229                 } else {
 230                         /* write */
 231                         retval = i2c_sendbytes(i2c_adap, &msgs[i], i+1 == num);
 232                         if (retval < 0)
 233                                 goto err;
 234                 }
 235         }
 236         return num;
 237
 238  err:
 239         return retval;
 240 }
 241
 242 static int attach_inform(struct i2c_client *client)
 243 {
 244         struct cx23885_dev *dev = i2c_get_adapdata(client->adapter);
 245
 246         dprintk(1, "%s i2c attach [addr=0x%x,client=%s]\n",
 247                 client->driver->driver.name, client->addr, client->name);
 248
 249         if (!client->driver->command)
 250                 return 0;
 251
 252         return 0;
 253 }
 254
 255 static int detach_inform(struct i2c_client *client)
 256 {
 257         struct cx23885_dev *dev = i2c_get_adapdata(client->adapter);
 258
 259         dprintk(1, "i2c detach [client=%s]\n", client->name);
 260
 261         return 0;
 262 }
 263
 264 void cx23885_call_i2c_clients(struct cx23885_i2c *bus, unsigned int cmd, void *arg)
 265 {
 266 //      struct cx23885_dev *dev = bus->dev;
 267
 268         if (bus->i2c_rc != 0)
 269                 return;
 270
 271                 i2c_clients_command(&bus->i2c_adap, cmd, arg);
 272 }
 273
 274 static int cx23885_algo_control(struct i2c_adapter *adap,
 275                                 unsigned int cmd, unsigned long arg)
 276 {
 277         return 0;
 278 }
 279
 280 static u32 cx23885_functionality(struct i2c_adapter *adap)
 281 {
 282         return I2C_FUNC_SMBUS_EMUL;
 283 }
 284
 285 static struct i2c_algorithm cx23885_i2c_algo_template = {
 286         .master_xfer    = i2c_xfer,
 287         .algo_control   = cx23885_algo_control,
 288         .functionality  = cx23885_functionality,
 289 };
 290
 291 /* ----------------------------------------------------------------------- */
 292
 293 static struct i2c_adapter cx23885_i2c_adap_template = {
 294         .name              = "cx23885",
 295         .owner             = THIS_MODULE,
 296         .id                = I2C_HW_B_CX23885,
 297         .algo              = &cx23885_i2c_algo_template,
 298 //      .class             = I2C_CLASS_TV_ANALOG,
 299         .client_register   = attach_inform,
 300         .client_unregister = detach_inform,
 301 };
 302
 303 static struct i2c_client cx23885_i2c_client_template = {
 304         .name   = "cx23885 internal",
 305 };
 306
 307 static char *i2c_devs[128] = {
 308         [ 0x32 >> 1 ] = "cx24227",
 309         [ 0x88 >> 1 ] = "cx25837",
 310         [ 0x84 >> 1 ] = "tda8295",
 311         [ 0xa0 >> 1 ] = "eeprom",
 312         [ 0xc0 >> 1 ] = "mt2131/tda8275",
 313         [ 0xc2 >> 1 ] = "mt2131/tda8275",
 314 };
 315
 316 static void do_i2c_scan(char *name, struct i2c_client *c)
 317 {
 318         unsigned char buf;
 319         int i,rc;
 320
 321         for (i = 0; i < 128; i++) {
 322                 c->addr = i;
 323                 rc = i2c_master_recv(c,&buf,0);
 324                 if (rc < 0)
 325                         continue;
 326                 printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
 327                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 328         }
 329 }
 330
 331 /* init + register i2c algo-bit adapter */
 332 int cx23885_i2c_register(struct cx23885_i2c *bus)
 333 {
 334         struct cx23885_dev *dev = bus->dev;
 335
 336         dprintk(1, "%s(bus = %d)\n", __FUNCTION__, bus->nr);
 337
 338         memcpy(&bus->i2c_adap, &cx23885_i2c_adap_template, sizeof(bus->i2c_adap));
 339         memcpy(&bus->i2c_algo, &cx23885_i2c_algo_template, sizeof(bus->i2c_algo));
 340         memcpy(&bus->i2c_client, &cx23885_i2c_client_template, sizeof(bus->i2c_client));
 341
 342         bus->i2c_adap.dev.parent = &dev->pci->dev;
 343
 344         strlcpy(bus->i2c_adap.name, bus->dev->name, sizeof(bus->i2c_adap.name));
 345         bus->i2c_algo.data = bus;
 346         bus->i2c_adap.algo_data = bus;
 347         i2c_add_adapter(&bus->i2c_adap);
 348
 349         bus->i2c_client.adapter = &bus->i2c_adap;
 350
 351         if (0 == bus->i2c_rc) {
 352                 printk("%s: i2c bus %d registered\n", dev->name, bus->nr);
 353                 if (i2c_scan)
 354                         do_i2c_scan(dev->name, &bus->i2c_client);
 355         } else
 356                 printk("%s: i2c bus %d register FAILED\n", dev->name, bus->nr);
 357
 358         return bus->i2c_rc;
 359 }
 360
 361 int cx23885_i2c_unregister(struct cx23885_i2c *bus)
 362 {
 363         i2c_del_adapter(&bus->i2c_adap);
 364         return 0;
 365 }
 366
 367 /* ----------------------------------------------------------------------- */
 368
 369 EXPORT_SYMBOL(cx23885_call_i2c_clients);
 370
 371 /*
 372  * Local variables:
 373  * c-basic-offset: 8
 374  * End:
 375  */