drivers/media/usb/tm6000/tm6000-i2c.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // tm6000-i2c.c - driver for TM5600/TM6000/TM6010 USB video capture devices
   3 //
   4 // Copyright (c) 2006-2007 Mauro Carvalho Chehab <mchehab@kernel.org>
   5 //
   6 // Copyright (c) 2007 Michel Ludwig <michel.ludwig@gmail.com>
   7 //      - Fix SMBus Read Byte command
   8
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <linux/usb.h>
  12 #include <linux/i2c.h>
  13
  14 #include "tm6000.h"
  15 #include "tm6000-regs.h"
  16 #include <media/v4l2-common.h>
  17 #include <media/tuner.h>
  18 #include "tuner-xc2028.h"
  19
  20
  21 /* ----------------------------------------------------------- */
  22
  23 static unsigned int i2c_debug;
  24 module_param(i2c_debug, int, 0644);
  25 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  26
  27 #define i2c_dprintk(lvl, fmt, args...) if (i2c_debug >= lvl) do { \
  28                         printk(KERN_DEBUG "%s at %s: " fmt, \
  29                         dev->name, __func__, ##args); } while (0)
  30
  31 static int tm6000_i2c_send_regs(struct tm6000_core *dev, unsigned char addr,
  32                                 __u8 reg, char *buf, int len)
  33 {
  34         int rc;
  35         unsigned int i2c_packet_limit = 16;
  36
  37         if (dev->dev_type == TM6010)
  38                 i2c_packet_limit = 80;
  39
  40         if (!buf)
  41                 return -1;
  42
  43         if (len < 1 || len > i2c_packet_limit) {
  44                 printk(KERN_ERR "Incorrect length of i2c packet = %d, limit set to %d\n",
  45                         len, i2c_packet_limit);
  46                 return -1;
  47         }
  48
  49         /* capture mutex */
  50         rc = tm6000_read_write_usb(dev, USB_DIR_OUT | USB_TYPE_VENDOR |
  51                 USB_RECIP_DEVICE, REQ_16_SET_GET_I2C_WR1_RDN,
  52                 addr | reg << 8, 0, buf, len);
  53
  54         if (rc < 0) {
  55                 /* release mutex */
  56                 return rc;
  57         }
  58
  59         /* release mutex */
  60         return rc;
  61 }
  62
  63 /* Generic read - doesn't work fine with 16bit registers */
  64 static int tm6000_i2c_recv_regs(struct tm6000_core *dev, unsigned char addr,
  65                                 __u8 reg, char *buf, int len)
  66 {
  67         int rc;
  68         u8 b[2];
  69         unsigned int i2c_packet_limit = 16;
  70
  71         if (dev->dev_type == TM6010)
  72                 i2c_packet_limit = 64;
  73
  74         if (!buf)
  75                 return -1;
  76
  77         if (len < 1 || len > i2c_packet_limit) {
  78                 printk(KERN_ERR "Incorrect length of i2c packet = %d, limit set to %d\n",
  79                         len, i2c_packet_limit);
  80                 return -1;
  81         }
  82
  83         /* capture mutex */
  84         if ((dev->caps.has_zl10353) && (dev->demod_addr << 1 == addr) && (reg % 2 == 0)) {
  85                 /*
  86                  * Workaround an I2C bug when reading from zl10353
  87                  */
  88                 reg -= 1;
  89                 len += 1;
  90
  91                 rc = tm6000_read_write_usb(dev, USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
  92                         REQ_16_SET_GET_I2C_WR1_RDN, addr | reg << 8, 0, b, len);
  93
  94                 *buf = b[1];
  95         } else {
  96                 rc = tm6000_read_write_usb(dev, USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
  97                         REQ_16_SET_GET_I2C_WR1_RDN, addr | reg << 8, 0, buf, len);
  98         }
  99
 100         /* release mutex */
 101         return rc;
 102 }
 103
 104 /*
 105  * read from a 16bit register
 106  * for example xc2028, xc3028 or xc3028L
 107  */
 108 static int tm6000_i2c_recv_regs16(struct tm6000_core *dev, unsigned char addr,
 109                                   __u16 reg, char *buf, int len)
 110 {
 111         int rc;
 112         unsigned char ureg;
 113
 114         if (!buf || len != 2)
 115                 return -1;
 116
 117         /* capture mutex */
 118         if (dev->dev_type == TM6010) {
 119                 ureg = reg & 0xFF;
 120                 rc = tm6000_read_write_usb(dev, USB_DIR_OUT | USB_TYPE_VENDOR |
 121                         USB_RECIP_DEVICE, REQ_16_SET_GET_I2C_WR1_RDN,
 122                         addr | (reg & 0xFF00), 0, &ureg, 1);
 123
 124                 if (rc < 0) {
 125                         /* release mutex */
 126                         return rc;
 127                 }
 128
 129                 rc = tm6000_read_write_usb(dev, USB_DIR_IN | USB_TYPE_VENDOR |
 130                         USB_RECIP_DEVICE, REQ_35_AFTEK_TUNER_READ,
 131                         reg, 0, buf, len);
 132         } else {
 133                 rc = tm6000_read_write_usb(dev, USB_DIR_IN | USB_TYPE_VENDOR |
 134                         USB_RECIP_DEVICE, REQ_14_SET_GET_I2C_WR2_RDN,
 135                         addr, reg, buf, len);
 136         }
 137
 138         /* release mutex */
 139         return rc;
 140 }
 141
 142 static int tm6000_i2c_xfer(struct i2c_adapter *i2c_adap,
 143                            struct i2c_msg msgs[], int num)
 144 {
 145         struct tm6000_core *dev = i2c_adap->algo_data;
 146         int addr, rc, i, byte;
 147
 148         if (num <= 0)
 149                 return 0;
 150         for (i = 0; i < num; i++) {
 151                 addr = (msgs[i].addr << 1) & 0xff;
 152                 i2c_dprintk(2, "%s %s addr=0x%x len=%d:",
 153                          (msgs[i].flags & I2C_M_RD) ? "read" : "write",
 154                          i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
 155                 if (msgs[i].flags & I2C_M_RD) {
 156                         /* read request without preceding register selection */
 157                         /*
 158                          * The TM6000 only supports a read transaction
 159                          * immediately after a 1 or 2 byte write to select
 160                          * a register.  We cannot fulfil this request.
 161                          */
 162                         i2c_dprintk(2, " read without preceding write not supported");
 163                         rc = -EOPNOTSUPP;
 164                         goto err;
 165                 } else if (i + 1 < num && msgs[i].len <= 2 &&
 166                            (msgs[i + 1].flags & I2C_M_RD) &&
 167                            msgs[i].addr == msgs[i + 1].addr) {
 168                         /* 1 or 2 byte write followed by a read */
 169                         if (i2c_debug >= 2)
 170                                 for (byte = 0; byte < msgs[i].len; byte++)
 171                                         printk(KERN_CONT " %02x", msgs[i].buf[byte]);
 172                         i2c_dprintk(2, "; joined to read %s len=%d:",
 173                                     i == num - 2 ? "stop" : "nonstop",
 174                                     msgs[i + 1].len);
 175
 176                         if (msgs[i].len == 2) {
 177                                 rc = tm6000_i2c_recv_regs16(dev, addr,
 178                                         msgs[i].buf[0] << 8 | msgs[i].buf[1],
 179                                         msgs[i + 1].buf, msgs[i + 1].len);
 180                         } else {
 181                                 rc = tm6000_i2c_recv_regs(dev, addr, msgs[i].buf[0],
 182                                         msgs[i + 1].buf, msgs[i + 1].len);
 183                         }
 184
 185                         i++;
 186
 187                         if (addr == dev->tuner_addr << 1) {
 188                                 tm6000_set_reg(dev, REQ_50_SET_START, 0, 0);
 189                                 tm6000_set_reg(dev, REQ_51_SET_STOP, 0, 0);
 190                         }
 191                         if (i2c_debug >= 2)
 192                                 for (byte = 0; byte < msgs[i].len; byte++)
 193                                         printk(KERN_CONT " %02x", msgs[i].buf[byte]);
 194                 } else {
 195                         /* write bytes */
 196                         if (i2c_debug >= 2)
 197                                 for (byte = 0; byte < msgs[i].len; byte++)
 198                                         printk(KERN_CONT " %02x", msgs[i].buf[byte]);
 199                         rc = tm6000_i2c_send_regs(dev, addr, msgs[i].buf[0],
 200                                 msgs[i].buf + 1, msgs[i].len - 1);
 201                 }
 202                 if (i2c_debug >= 2)
 203                         printk(KERN_CONT "\n");
 204                 if (rc < 0)
 205                         goto err;
 206         }
 207
 208         return num;
 209 err:
 210         i2c_dprintk(2, " ERROR: %i\n", rc);
 211         return rc;
 212 }
 213
 214 static int tm6000_i2c_eeprom(struct tm6000_core *dev)
 215 {
 216         int i, rc;
 217         unsigned char *p = dev->eedata;
 218         unsigned char bytes[17];
 219
 220         dev->i2c_client.addr = 0xa0 >> 1;
 221         dev->eedata_size = 0;
 222
 223         bytes[16] = '\0';
 224         for (i = 0; i < sizeof(dev->eedata); ) {
 225                 *p = i;
 226                 rc = tm6000_i2c_recv_regs(dev, 0xa0, i, p, 1);
 227                 if (rc < 1) {
 228                         if (p == dev->eedata)
 229                                 goto noeeprom;
 230                         else {
 231                                 printk(KERN_WARNING
 232                                 "%s: i2c eeprom read error (err=%d)\n",
 233                                 dev->name, rc);
 234                         }
 235                         return -EINVAL;
 236                 }
 237                 dev->eedata_size++;
 238                 p++;
 239                 if (0 == (i % 16))
 240                         printk(KERN_INFO "%s: i2c eeprom %02x:", dev->name, i);
 241                 printk(KERN_CONT " %02x", dev->eedata[i]);
 242                 if ((dev->eedata[i] >= ' ') && (dev->eedata[i] <= 'z'))
 243                         bytes[i%16] = dev->eedata[i];
 244                 else
 245                         bytes[i%16] = '.';
 246
 247                 i++;
 248
 249                 if (0 == (i % 16)) {
 250                         bytes[16] = '\0';
 251                         printk(KERN_CONT "  %s\n", bytes);
 252                 }
 253         }
 254         if (0 != (i%16)) {
 255                 bytes[i%16] = '\0';
 256                 for (i %= 16; i < 16; i++)
 257                         printk(KERN_CONT "   ");
 258                 printk(KERN_CONT "  %s\n", bytes);
 259         }
 260
 261         return 0;
 262
 263 noeeprom:
 264         printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
 265                dev->name, rc);
 266         return -EINVAL;
 267 }
 268
 269 /* ----------------------------------------------------------- */
 270
 271 /*
 272  * functionality()
 273  */
 274 static u32 functionality(struct i2c_adapter *adap)
 275 {
 276         return I2C_FUNC_SMBUS_EMUL;
 277 }
 278
 279 static const struct i2c_algorithm tm6000_algo = {
 280         .master_xfer   = tm6000_i2c_xfer,
 281         .functionality = functionality,
 282 };
 283
 284 /* ----------------------------------------------------------- */
 285
 286 /*
 287  * tm6000_i2c_register()
 288  * register i2c bus
 289  */
 290 int tm6000_i2c_register(struct tm6000_core *dev)
 291 {
 292         int rc;
 293
 294         dev->i2c_adap.owner = THIS_MODULE;
 295         dev->i2c_adap.algo = &tm6000_algo;
 296         dev->i2c_adap.dev.parent = &dev->udev->dev;
 297         strlcpy(dev->i2c_adap.name, dev->name, sizeof(dev->i2c_adap.name));
 298         dev->i2c_adap.algo_data = dev;
 299         i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
 300         rc = i2c_add_adapter(&dev->i2c_adap);
 301         if (rc)
 302                 return rc;
 303
 304         dev->i2c_client.adapter = &dev->i2c_adap;
 305         strlcpy(dev->i2c_client.name, "tm6000 internal", I2C_NAME_SIZE);
 306         tm6000_i2c_eeprom(dev);
 307
 308         return 0;
 309 }
 310
 311 /*
 312  * tm6000_i2c_unregister()
 313  * unregister i2c_bus
 314  */
 315 int tm6000_i2c_unregister(struct tm6000_core *dev)
 316 {
 317         i2c_del_adapter(&dev->i2c_adap);
 318         return 0;
 319 }