Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 1 | /* |
| 2 | I2C functions |
| 3 | Copyright (C) 2003-2004 Kevin Thayer <nufan_wfk at yahoo.com> |
| 4 | Copyright (C) 2005-2007 Hans Verkuil <hverkuil@xs4all.nl> |
| 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 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | |
| 21 | /* |
| 22 | This file includes an i2c implementation that was reverse engineered |
| 23 | from the Hauppauge windows driver. Older ivtv versions used i2c-algo-bit, |
| 24 | which whilst fine under most circumstances, had trouble with the Zilog |
| 25 | CPU on the PVR-150 which handles IR functions (occasional inability to |
| 26 | communicate with the chip until it was reset) and also with the i2c |
| 27 | bus being completely unreachable when multiple PVR cards were present. |
| 28 | |
| 29 | The implementation is very similar to i2c-algo-bit, but there are enough |
| 30 | subtle differences that the two are hard to merge. The general strategy |
| 31 | employed by i2c-algo-bit is to use udelay() to implement the timing |
| 32 | when putting out bits on the scl/sda lines. The general strategy taken |
| 33 | here is to poll the lines for state changes (see ivtv_waitscl and |
| 34 | ivtv_waitsda). In addition there are small delays at various locations |
| 35 | which poll the SCL line 5 times (ivtv_scldelay). I would guess that |
| 36 | since this is memory mapped I/O that the length of those delays is tied |
| 37 | to the PCI bus clock. There is some extra code to do with recovery |
| 38 | and retries. Since it is not known what causes the actual i2c problems |
| 39 | in the first place, the only goal if one was to attempt to use |
| 40 | i2c-algo-bit would be to try to make it follow the same code path. |
| 41 | This would be a lot of work, and I'm also not convinced that it would |
| 42 | provide a generic benefit to i2c-algo-bit. Therefore consider this |
| 43 | an engineering solution -- not pretty, but it works. |
| 44 | |
| 45 | Some more general comments about what we are doing: |
| 46 | |
| 47 | The i2c bus is a 2 wire serial bus, with clock (SCL) and data (SDA) |
| 48 | lines. To communicate on the bus (as a master, we don't act as a slave), |
| 49 | we first initiate a start condition (ivtv_start). We then write the |
| 50 | address of the device that we want to communicate with, along with a flag |
| 51 | that indicates whether this is a read or a write. The slave then issues |
| 52 | an ACK signal (ivtv_ack), which tells us that it is ready for reading / |
| 53 | writing. We then proceed with reading or writing (ivtv_read/ivtv_write), |
| 54 | and finally issue a stop condition (ivtv_stop) to make the bus available |
| 55 | to other masters. |
| 56 | |
| 57 | There is an additional form of transaction where a write may be |
| 58 | immediately followed by a read. In this case, there is no intervening |
| 59 | stop condition. (Only the msp3400 chip uses this method of data transfer). |
| 60 | */ |
| 61 | |
| 62 | #include "ivtv-driver.h" |
| 63 | #include "ivtv-cards.h" |
| 64 | #include "ivtv-gpio.h" |
Hans Verkuil | 83df8e7 | 2007-03-10 06:54:58 -0300 | [diff] [blame] | 65 | #include "ivtv-i2c.h" |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 66 | |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 67 | /* i2c implementation for cx23415/6 chip, ivtv project. |
| 68 | * Author: Kevin Thayer (nufan_wfk at yahoo.com) |
| 69 | */ |
| 70 | /* i2c stuff */ |
| 71 | #define IVTV_REG_I2C_SETSCL_OFFSET 0x7000 |
| 72 | #define IVTV_REG_I2C_SETSDA_OFFSET 0x7004 |
| 73 | #define IVTV_REG_I2C_GETSCL_OFFSET 0x7008 |
| 74 | #define IVTV_REG_I2C_GETSDA_OFFSET 0x700c |
| 75 | |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 76 | #define IVTV_CS53L32A_I2C_ADDR 0x11 |
Hans Verkuil | e2a1774 | 2007-10-30 05:50:03 -0300 | [diff] [blame] | 77 | #define IVTV_M52790_I2C_ADDR 0x48 |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 78 | #define IVTV_CX25840_I2C_ADDR 0x44 |
| 79 | #define IVTV_SAA7115_I2C_ADDR 0x21 |
| 80 | #define IVTV_SAA7127_I2C_ADDR 0x44 |
| 81 | #define IVTV_SAA717x_I2C_ADDR 0x21 |
| 82 | #define IVTV_MSP3400_I2C_ADDR 0x40 |
| 83 | #define IVTV_HAUPPAUGE_I2C_ADDR 0x50 |
| 84 | #define IVTV_WM8739_I2C_ADDR 0x1a |
| 85 | #define IVTV_WM8775_I2C_ADDR 0x1b |
| 86 | #define IVTV_TEA5767_I2C_ADDR 0x60 |
| 87 | #define IVTV_UPD64031A_I2C_ADDR 0x12 |
| 88 | #define IVTV_UPD64083_I2C_ADDR 0x5c |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 89 | #define IVTV_VP27SMPX_I2C_ADDR 0x5b |
| 90 | #define IVTV_M52790_I2C_ADDR 0x48 |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 91 | |
| 92 | /* This array should match the IVTV_HW_ defines */ |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 93 | static const u8 hw_addrs[] = { |
| 94 | IVTV_CX25840_I2C_ADDR, |
| 95 | IVTV_SAA7115_I2C_ADDR, |
| 96 | IVTV_SAA7127_I2C_ADDR, |
| 97 | IVTV_MSP3400_I2C_ADDR, |
| 98 | 0, |
| 99 | IVTV_WM8775_I2C_ADDR, |
| 100 | IVTV_CS53L32A_I2C_ADDR, |
| 101 | 0, |
| 102 | IVTV_SAA7115_I2C_ADDR, |
| 103 | IVTV_UPD64031A_I2C_ADDR, |
| 104 | IVTV_UPD64083_I2C_ADDR, |
| 105 | IVTV_SAA717x_I2C_ADDR, |
| 106 | IVTV_WM8739_I2C_ADDR, |
| 107 | IVTV_VP27SMPX_I2C_ADDR, |
| 108 | IVTV_M52790_I2C_ADDR, |
| 109 | 0 /* IVTV_HW_GPIO dummy driver ID */ |
| 110 | }; |
| 111 | |
| 112 | /* This array should match the IVTV_HW_ defines */ |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 113 | static const char *hw_modules[] = { |
| 114 | "cx25840", |
| 115 | "saa7115", |
| 116 | "saa7127", |
| 117 | "msp3400", |
| 118 | "tuner", |
| 119 | "wm8775", |
| 120 | "cs53l32a", |
| 121 | NULL, |
| 122 | "saa7115", |
| 123 | "upd64031a", |
| 124 | "upd64083", |
| 125 | "saa717x", |
| 126 | "wm8739", |
| 127 | "vp27smpx", |
| 128 | "m52790", |
| 129 | NULL |
| 130 | }; |
| 131 | |
| 132 | /* This array should match the IVTV_HW_ defines */ |
Jean Delvare | af29486 | 2008-05-18 20:49:40 +0200 | [diff] [blame] | 133 | static const char * const hw_devicenames[] = { |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 134 | "cx25840", |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 135 | "saa7115", |
Jean Delvare | 5daed07 | 2008-07-17 13:18:31 -0300 | [diff] [blame] | 136 | "saa7127_auto", /* saa7127 or saa7129 */ |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 137 | "msp3400", |
| 138 | "tuner", |
| 139 | "wm8775", |
| 140 | "cs53l32a", |
| 141 | "tveeprom", |
Jean Delvare | af29486 | 2008-05-18 20:49:40 +0200 | [diff] [blame] | 142 | "saa7114", |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 143 | "upd64031a", |
| 144 | "upd64083", |
| 145 | "saa717x", |
| 146 | "wm8739", |
Hans Verkuil | ac24743 | 2007-07-27 06:56:50 -0300 | [diff] [blame] | 147 | "vp27smpx", |
Hans Verkuil | e2a1774 | 2007-10-30 05:50:03 -0300 | [diff] [blame] | 148 | "m52790", |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 149 | "gpio", |
| 150 | }; |
| 151 | |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 152 | int ivtv_i2c_register(struct ivtv *itv, unsigned idx) |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 153 | { |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 154 | struct v4l2_subdev *sd; |
| 155 | struct i2c_adapter *adap = &itv->i2c_adap; |
| 156 | const char *mod = hw_modules[idx]; |
| 157 | const char *type = hw_devicenames[idx]; |
| 158 | u32 hw = 1 << idx; |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 159 | |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 160 | if (idx >= ARRAY_SIZE(hw_addrs)) |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 161 | return -1; |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 162 | if (hw == IVTV_HW_TUNER) { |
| 163 | /* special tuner handling */ |
Hans Verkuil | e6574f2 | 2009-04-01 03:57:53 -0300 | [diff] [blame] | 164 | sd = v4l2_i2c_new_probed_subdev(&itv->v4l2_dev, |
| 165 | adap, mod, type, |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 166 | itv->card_i2c->radio); |
| 167 | if (sd) |
| 168 | sd->grp_id = 1 << idx; |
Hans Verkuil | e6574f2 | 2009-04-01 03:57:53 -0300 | [diff] [blame] | 169 | sd = v4l2_i2c_new_probed_subdev(&itv->v4l2_dev, |
| 170 | adap, mod, type, |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 171 | itv->card_i2c->demod); |
| 172 | if (sd) |
| 173 | sd->grp_id = 1 << idx; |
Hans Verkuil | e6574f2 | 2009-04-01 03:57:53 -0300 | [diff] [blame] | 174 | sd = v4l2_i2c_new_probed_subdev(&itv->v4l2_dev, |
| 175 | adap, mod, type, |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 176 | itv->card_i2c->tv); |
| 177 | if (sd) |
| 178 | sd->grp_id = 1 << idx; |
| 179 | return sd ? 0 : -1; |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 180 | } |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 181 | if (!hw_addrs[idx]) |
| 182 | return -1; |
| 183 | if (hw == IVTV_HW_UPD64031A || hw == IVTV_HW_UPD6408X) { |
Hans Verkuil | 1792f68 | 2009-03-30 11:47:55 -0300 | [diff] [blame^] | 184 | sd = v4l2_i2c_new_probed_subdev_addr(&itv->v4l2_dev, |
| 185 | adap, mod, type, hw_addrs[idx]); |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 186 | } else { |
Hans Verkuil | e6574f2 | 2009-04-01 03:57:53 -0300 | [diff] [blame] | 187 | sd = v4l2_i2c_new_subdev(&itv->v4l2_dev, |
| 188 | adap, mod, type, hw_addrs[idx]); |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 189 | } |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 190 | if (sd) |
| 191 | sd->grp_id = 1 << idx; |
| 192 | return sd ? 0 : -1; |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 193 | } |
| 194 | |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 195 | struct v4l2_subdev *ivtv_find_hw(struct ivtv *itv, u32 hw) |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 196 | { |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 197 | struct v4l2_subdev *result = NULL; |
| 198 | struct v4l2_subdev *sd; |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 199 | |
Hans Verkuil | 8ac05ae | 2009-02-07 07:02:27 -0300 | [diff] [blame] | 200 | spin_lock(&itv->v4l2_dev.lock); |
| 201 | v4l2_device_for_each_subdev(sd, &itv->v4l2_dev) { |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 202 | if (sd->grp_id == hw) { |
| 203 | result = sd; |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 204 | break; |
| 205 | } |
| 206 | } |
Hans Verkuil | 8ac05ae | 2009-02-07 07:02:27 -0300 | [diff] [blame] | 207 | spin_unlock(&itv->v4l2_dev.lock); |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 208 | return result; |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 209 | } |
| 210 | |
| 211 | /* Set the serial clock line to the desired state */ |
| 212 | static void ivtv_setscl(struct ivtv *itv, int state) |
| 213 | { |
| 214 | /* write them out */ |
| 215 | /* write bits are inverted */ |
| 216 | write_reg(~state, IVTV_REG_I2C_SETSCL_OFFSET); |
| 217 | } |
| 218 | |
| 219 | /* Set the serial data line to the desired state */ |
| 220 | static void ivtv_setsda(struct ivtv *itv, int state) |
| 221 | { |
| 222 | /* write them out */ |
| 223 | /* write bits are inverted */ |
| 224 | write_reg(~state & 1, IVTV_REG_I2C_SETSDA_OFFSET); |
| 225 | } |
| 226 | |
| 227 | /* Read the serial clock line */ |
| 228 | static int ivtv_getscl(struct ivtv *itv) |
| 229 | { |
| 230 | return read_reg(IVTV_REG_I2C_GETSCL_OFFSET) & 1; |
| 231 | } |
| 232 | |
| 233 | /* Read the serial data line */ |
| 234 | static int ivtv_getsda(struct ivtv *itv) |
| 235 | { |
| 236 | return read_reg(IVTV_REG_I2C_GETSDA_OFFSET) & 1; |
| 237 | } |
| 238 | |
| 239 | /* Implement a short delay by polling the serial clock line */ |
| 240 | static void ivtv_scldelay(struct ivtv *itv) |
| 241 | { |
| 242 | int i; |
| 243 | |
| 244 | for (i = 0; i < 5; ++i) |
| 245 | ivtv_getscl(itv); |
| 246 | } |
| 247 | |
| 248 | /* Wait for the serial clock line to become set to a specific value */ |
| 249 | static int ivtv_waitscl(struct ivtv *itv, int val) |
| 250 | { |
| 251 | int i; |
| 252 | |
| 253 | ivtv_scldelay(itv); |
| 254 | for (i = 0; i < 1000; ++i) { |
| 255 | if (ivtv_getscl(itv) == val) |
| 256 | return 1; |
| 257 | } |
| 258 | return 0; |
| 259 | } |
| 260 | |
| 261 | /* Wait for the serial data line to become set to a specific value */ |
| 262 | static int ivtv_waitsda(struct ivtv *itv, int val) |
| 263 | { |
| 264 | int i; |
| 265 | |
| 266 | ivtv_scldelay(itv); |
| 267 | for (i = 0; i < 1000; ++i) { |
| 268 | if (ivtv_getsda(itv) == val) |
| 269 | return 1; |
| 270 | } |
| 271 | return 0; |
| 272 | } |
| 273 | |
| 274 | /* Wait for the slave to issue an ACK */ |
| 275 | static int ivtv_ack(struct ivtv *itv) |
| 276 | { |
| 277 | int ret = 0; |
| 278 | |
| 279 | if (ivtv_getscl(itv) == 1) { |
Hans Verkuil | 11d2876 | 2007-07-17 12:47:38 -0300 | [diff] [blame] | 280 | IVTV_DEBUG_HI_I2C("SCL was high starting an ack\n"); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 281 | ivtv_setscl(itv, 0); |
| 282 | if (!ivtv_waitscl(itv, 0)) { |
| 283 | IVTV_DEBUG_I2C("Could not set SCL low starting an ack\n"); |
| 284 | return -EREMOTEIO; |
| 285 | } |
| 286 | } |
| 287 | ivtv_setsda(itv, 1); |
| 288 | ivtv_scldelay(itv); |
| 289 | ivtv_setscl(itv, 1); |
| 290 | if (!ivtv_waitsda(itv, 0)) { |
| 291 | IVTV_DEBUG_I2C("Slave did not ack\n"); |
| 292 | ret = -EREMOTEIO; |
| 293 | } |
| 294 | ivtv_setscl(itv, 0); |
| 295 | if (!ivtv_waitscl(itv, 0)) { |
| 296 | IVTV_DEBUG_I2C("Failed to set SCL low after ACK\n"); |
| 297 | ret = -EREMOTEIO; |
| 298 | } |
| 299 | return ret; |
| 300 | } |
| 301 | |
| 302 | /* Write a single byte to the i2c bus and wait for the slave to ACK */ |
| 303 | static int ivtv_sendbyte(struct ivtv *itv, unsigned char byte) |
| 304 | { |
| 305 | int i, bit; |
| 306 | |
Hans Verkuil | 11d2876 | 2007-07-17 12:47:38 -0300 | [diff] [blame] | 307 | IVTV_DEBUG_HI_I2C("write %x\n",byte); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 308 | for (i = 0; i < 8; ++i, byte<<=1) { |
| 309 | ivtv_setscl(itv, 0); |
| 310 | if (!ivtv_waitscl(itv, 0)) { |
| 311 | IVTV_DEBUG_I2C("Error setting SCL low\n"); |
| 312 | return -EREMOTEIO; |
| 313 | } |
| 314 | bit = (byte>>7)&1; |
| 315 | ivtv_setsda(itv, bit); |
| 316 | if (!ivtv_waitsda(itv, bit)) { |
| 317 | IVTV_DEBUG_I2C("Error setting SDA\n"); |
| 318 | return -EREMOTEIO; |
| 319 | } |
| 320 | ivtv_setscl(itv, 1); |
| 321 | if (!ivtv_waitscl(itv, 1)) { |
| 322 | IVTV_DEBUG_I2C("Slave not ready for bit\n"); |
| 323 | return -EREMOTEIO; |
| 324 | } |
| 325 | } |
| 326 | ivtv_setscl(itv, 0); |
| 327 | if (!ivtv_waitscl(itv, 0)) { |
| 328 | IVTV_DEBUG_I2C("Error setting SCL low\n"); |
| 329 | return -EREMOTEIO; |
| 330 | } |
| 331 | return ivtv_ack(itv); |
| 332 | } |
| 333 | |
| 334 | /* Read a byte from the i2c bus and send a NACK if applicable (i.e. for the |
| 335 | final byte) */ |
| 336 | static int ivtv_readbyte(struct ivtv *itv, unsigned char *byte, int nack) |
| 337 | { |
| 338 | int i; |
| 339 | |
| 340 | *byte = 0; |
| 341 | |
| 342 | ivtv_setsda(itv, 1); |
| 343 | ivtv_scldelay(itv); |
| 344 | for (i = 0; i < 8; ++i) { |
| 345 | ivtv_setscl(itv, 0); |
| 346 | ivtv_scldelay(itv); |
| 347 | ivtv_setscl(itv, 1); |
| 348 | if (!ivtv_waitscl(itv, 1)) { |
| 349 | IVTV_DEBUG_I2C("Error setting SCL high\n"); |
| 350 | return -EREMOTEIO; |
| 351 | } |
| 352 | *byte = ((*byte)<<1)|ivtv_getsda(itv); |
| 353 | } |
| 354 | ivtv_setscl(itv, 0); |
| 355 | ivtv_scldelay(itv); |
| 356 | ivtv_setsda(itv, nack); |
| 357 | ivtv_scldelay(itv); |
| 358 | ivtv_setscl(itv, 1); |
| 359 | ivtv_scldelay(itv); |
| 360 | ivtv_setscl(itv, 0); |
| 361 | ivtv_scldelay(itv); |
Hans Verkuil | 11d2876 | 2007-07-17 12:47:38 -0300 | [diff] [blame] | 362 | IVTV_DEBUG_HI_I2C("read %x\n",*byte); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 363 | return 0; |
| 364 | } |
| 365 | |
| 366 | /* Issue a start condition on the i2c bus to alert slaves to prepare for |
| 367 | an address write */ |
| 368 | static int ivtv_start(struct ivtv *itv) |
| 369 | { |
| 370 | int sda; |
| 371 | |
| 372 | sda = ivtv_getsda(itv); |
| 373 | if (sda != 1) { |
Hans Verkuil | 11d2876 | 2007-07-17 12:47:38 -0300 | [diff] [blame] | 374 | IVTV_DEBUG_HI_I2C("SDA was low at start\n"); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 375 | ivtv_setsda(itv, 1); |
| 376 | if (!ivtv_waitsda(itv, 1)) { |
| 377 | IVTV_DEBUG_I2C("SDA stuck low\n"); |
| 378 | return -EREMOTEIO; |
| 379 | } |
| 380 | } |
| 381 | if (ivtv_getscl(itv) != 1) { |
| 382 | ivtv_setscl(itv, 1); |
| 383 | if (!ivtv_waitscl(itv, 1)) { |
| 384 | IVTV_DEBUG_I2C("SCL stuck low at start\n"); |
| 385 | return -EREMOTEIO; |
| 386 | } |
| 387 | } |
| 388 | ivtv_setsda(itv, 0); |
| 389 | ivtv_scldelay(itv); |
| 390 | return 0; |
| 391 | } |
| 392 | |
| 393 | /* Issue a stop condition on the i2c bus to release it */ |
| 394 | static int ivtv_stop(struct ivtv *itv) |
| 395 | { |
| 396 | int i; |
| 397 | |
| 398 | if (ivtv_getscl(itv) != 0) { |
Hans Verkuil | 11d2876 | 2007-07-17 12:47:38 -0300 | [diff] [blame] | 399 | IVTV_DEBUG_HI_I2C("SCL not low when stopping\n"); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 400 | ivtv_setscl(itv, 0); |
| 401 | if (!ivtv_waitscl(itv, 0)) { |
| 402 | IVTV_DEBUG_I2C("SCL could not be set low\n"); |
| 403 | } |
| 404 | } |
| 405 | ivtv_setsda(itv, 0); |
| 406 | ivtv_scldelay(itv); |
| 407 | ivtv_setscl(itv, 1); |
| 408 | if (!ivtv_waitscl(itv, 1)) { |
| 409 | IVTV_DEBUG_I2C("SCL could not be set high\n"); |
| 410 | return -EREMOTEIO; |
| 411 | } |
| 412 | ivtv_scldelay(itv); |
| 413 | ivtv_setsda(itv, 1); |
| 414 | if (!ivtv_waitsda(itv, 1)) { |
| 415 | IVTV_DEBUG_I2C("resetting I2C\n"); |
| 416 | for (i = 0; i < 16; ++i) { |
| 417 | ivtv_setscl(itv, 0); |
| 418 | ivtv_scldelay(itv); |
| 419 | ivtv_setscl(itv, 1); |
| 420 | ivtv_scldelay(itv); |
| 421 | ivtv_setsda(itv, 1); |
| 422 | } |
| 423 | ivtv_waitsda(itv, 1); |
| 424 | return -EREMOTEIO; |
| 425 | } |
| 426 | return 0; |
| 427 | } |
| 428 | |
| 429 | /* Write a message to the given i2c slave. do_stop may be 0 to prevent |
| 430 | issuing the i2c stop condition (when following with a read) */ |
| 431 | static int ivtv_write(struct ivtv *itv, unsigned char addr, unsigned char *data, u32 len, int do_stop) |
| 432 | { |
| 433 | int retry, ret = -EREMOTEIO; |
| 434 | u32 i; |
| 435 | |
| 436 | for (retry = 0; ret != 0 && retry < 8; ++retry) { |
| 437 | ret = ivtv_start(itv); |
| 438 | |
| 439 | if (ret == 0) { |
| 440 | ret = ivtv_sendbyte(itv, addr<<1); |
| 441 | for (i = 0; ret == 0 && i < len; ++i) |
| 442 | ret = ivtv_sendbyte(itv, data[i]); |
| 443 | } |
| 444 | if (ret != 0 || do_stop) { |
| 445 | ivtv_stop(itv); |
| 446 | } |
| 447 | } |
| 448 | if (ret) |
| 449 | IVTV_DEBUG_I2C("i2c write to %x failed\n", addr); |
| 450 | return ret; |
| 451 | } |
| 452 | |
| 453 | /* Read data from the given i2c slave. A stop condition is always issued. */ |
| 454 | static int ivtv_read(struct ivtv *itv, unsigned char addr, unsigned char *data, u32 len) |
| 455 | { |
| 456 | int retry, ret = -EREMOTEIO; |
| 457 | u32 i; |
| 458 | |
| 459 | for (retry = 0; ret != 0 && retry < 8; ++retry) { |
| 460 | ret = ivtv_start(itv); |
| 461 | if (ret == 0) |
| 462 | ret = ivtv_sendbyte(itv, (addr << 1) | 1); |
| 463 | for (i = 0; ret == 0 && i < len; ++i) { |
| 464 | ret = ivtv_readbyte(itv, &data[i], i == len - 1); |
| 465 | } |
| 466 | ivtv_stop(itv); |
| 467 | } |
| 468 | if (ret) |
| 469 | IVTV_DEBUG_I2C("i2c read from %x failed\n", addr); |
| 470 | return ret; |
| 471 | } |
| 472 | |
| 473 | /* Kernel i2c transfer implementation. Takes a number of messages to be read |
| 474 | or written. If a read follows a write, this will occur without an |
| 475 | intervening stop condition */ |
| 476 | static int ivtv_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num) |
| 477 | { |
Hans Verkuil | 8ac05ae | 2009-02-07 07:02:27 -0300 | [diff] [blame] | 478 | struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap); |
| 479 | struct ivtv *itv = to_ivtv(v4l2_dev); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 480 | int retval; |
| 481 | int i; |
| 482 | |
| 483 | mutex_lock(&itv->i2c_bus_lock); |
| 484 | for (i = retval = 0; retval == 0 && i < num; i++) { |
| 485 | if (msgs[i].flags & I2C_M_RD) |
| 486 | retval = ivtv_read(itv, msgs[i].addr, msgs[i].buf, msgs[i].len); |
| 487 | else { |
| 488 | /* if followed by a read, don't stop */ |
| 489 | int stop = !(i + 1 < num && msgs[i + 1].flags == I2C_M_RD); |
| 490 | |
| 491 | retval = ivtv_write(itv, msgs[i].addr, msgs[i].buf, msgs[i].len, stop); |
| 492 | } |
| 493 | } |
| 494 | mutex_unlock(&itv->i2c_bus_lock); |
| 495 | return retval ? retval : num; |
| 496 | } |
| 497 | |
| 498 | /* Kernel i2c capabilities */ |
| 499 | static u32 ivtv_functionality(struct i2c_adapter *adap) |
| 500 | { |
| 501 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
| 502 | } |
| 503 | |
| 504 | static struct i2c_algorithm ivtv_algo = { |
| 505 | .master_xfer = ivtv_xfer, |
| 506 | .functionality = ivtv_functionality, |
| 507 | }; |
| 508 | |
| 509 | /* template for our-bit banger */ |
| 510 | static struct i2c_adapter ivtv_i2c_adap_hw_template = { |
| 511 | .name = "ivtv i2c driver", |
| 512 | .id = I2C_HW_B_CX2341X, |
| 513 | .algo = &ivtv_algo, |
| 514 | .algo_data = NULL, /* filled from template */ |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 515 | .owner = THIS_MODULE, |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 516 | }; |
| 517 | |
| 518 | static void ivtv_setscl_old(void *data, int state) |
| 519 | { |
| 520 | struct ivtv *itv = (struct ivtv *)data; |
| 521 | |
| 522 | if (state) |
| 523 | itv->i2c_state |= 0x01; |
| 524 | else |
| 525 | itv->i2c_state &= ~0x01; |
| 526 | |
| 527 | /* write them out */ |
| 528 | /* write bits are inverted */ |
| 529 | write_reg(~itv->i2c_state, IVTV_REG_I2C_SETSCL_OFFSET); |
| 530 | } |
| 531 | |
| 532 | static void ivtv_setsda_old(void *data, int state) |
| 533 | { |
| 534 | struct ivtv *itv = (struct ivtv *)data; |
| 535 | |
| 536 | if (state) |
| 537 | itv->i2c_state |= 0x01; |
| 538 | else |
| 539 | itv->i2c_state &= ~0x01; |
| 540 | |
| 541 | /* write them out */ |
| 542 | /* write bits are inverted */ |
| 543 | write_reg(~itv->i2c_state, IVTV_REG_I2C_SETSDA_OFFSET); |
| 544 | } |
| 545 | |
| 546 | static int ivtv_getscl_old(void *data) |
| 547 | { |
| 548 | struct ivtv *itv = (struct ivtv *)data; |
| 549 | |
| 550 | return read_reg(IVTV_REG_I2C_GETSCL_OFFSET) & 1; |
| 551 | } |
| 552 | |
| 553 | static int ivtv_getsda_old(void *data) |
| 554 | { |
| 555 | struct ivtv *itv = (struct ivtv *)data; |
| 556 | |
| 557 | return read_reg(IVTV_REG_I2C_GETSDA_OFFSET) & 1; |
| 558 | } |
| 559 | |
| 560 | /* template for i2c-bit-algo */ |
| 561 | static struct i2c_adapter ivtv_i2c_adap_template = { |
| 562 | .name = "ivtv i2c driver", |
Jean Delvare | d998cc6 | 2007-12-22 18:28:22 -0300 | [diff] [blame] | 563 | .id = I2C_HW_B_CX2341X, |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 564 | .algo = NULL, /* set by i2c-algo-bit */ |
| 565 | .algo_data = NULL, /* filled from template */ |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 566 | .owner = THIS_MODULE, |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 567 | }; |
| 568 | |
Jean Delvare | aeb292d | 2007-08-23 15:45:41 -0300 | [diff] [blame] | 569 | static const struct i2c_algo_bit_data ivtv_i2c_algo_template = { |
| 570 | .setsda = ivtv_setsda_old, |
| 571 | .setscl = ivtv_setscl_old, |
| 572 | .getsda = ivtv_getsda_old, |
| 573 | .getscl = ivtv_getscl_old, |
Hans Verkuil | 89dab35 | 2008-01-07 06:46:26 -0200 | [diff] [blame] | 574 | .udelay = 10, |
Jean Delvare | aeb292d | 2007-08-23 15:45:41 -0300 | [diff] [blame] | 575 | .timeout = 200, |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 576 | }; |
| 577 | |
| 578 | static struct i2c_client ivtv_i2c_client_template = { |
Andrew Morton | a415783 | 2007-03-07 11:28:33 -0300 | [diff] [blame] | 579 | .name = "ivtv internal", |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 580 | }; |
| 581 | |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 582 | /* init + register i2c algo-bit adapter */ |
Adrian Bunk | 056827a | 2007-12-11 19:23:49 -0300 | [diff] [blame] | 583 | int init_ivtv_i2c(struct ivtv *itv) |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 584 | { |
| 585 | IVTV_DEBUG_I2C("i2c init\n"); |
| 586 | |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 587 | /* Sanity checks for the I2C hardware arrays. They must be the |
| 588 | * same size and GPIO must be the last entry. |
| 589 | */ |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 590 | if (ARRAY_SIZE(hw_devicenames) != ARRAY_SIZE(hw_addrs) || |
| 591 | ARRAY_SIZE(hw_devicenames) != ARRAY_SIZE(hw_modules) || |
| 592 | IVTV_HW_GPIO != (1 << (ARRAY_SIZE(hw_addrs) - 1))) { |
Hans Verkuil | d900920 | 2007-12-07 21:01:15 -0300 | [diff] [blame] | 593 | IVTV_ERR("Mismatched I2C hardware arrays\n"); |
| 594 | return -ENODEV; |
| 595 | } |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 596 | if (itv->options.newi2c > 0) { |
| 597 | memcpy(&itv->i2c_adap, &ivtv_i2c_adap_hw_template, |
| 598 | sizeof(struct i2c_adapter)); |
| 599 | } else { |
| 600 | memcpy(&itv->i2c_adap, &ivtv_i2c_adap_template, |
| 601 | sizeof(struct i2c_adapter)); |
| 602 | memcpy(&itv->i2c_algo, &ivtv_i2c_algo_template, |
| 603 | sizeof(struct i2c_algo_bit_data)); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 604 | } |
Hans Verkuil | 0e614cd | 2007-12-21 21:33:36 -0300 | [diff] [blame] | 605 | itv->i2c_algo.data = itv; |
| 606 | itv->i2c_adap.algo_data = &itv->i2c_algo; |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 607 | |
| 608 | sprintf(itv->i2c_adap.name + strlen(itv->i2c_adap.name), " #%d", |
Hans Verkuil | 67ec09f | 2008-11-29 19:38:23 -0300 | [diff] [blame] | 609 | itv->instance); |
Hans Verkuil | 8ac05ae | 2009-02-07 07:02:27 -0300 | [diff] [blame] | 610 | i2c_set_adapdata(&itv->i2c_adap, &itv->v4l2_dev); |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 611 | |
| 612 | memcpy(&itv->i2c_client, &ivtv_i2c_client_template, |
| 613 | sizeof(struct i2c_client)); |
| 614 | itv->i2c_client.adapter = &itv->i2c_adap; |
Hans Verkuil | 8ac05ae | 2009-02-07 07:02:27 -0300 | [diff] [blame] | 615 | itv->i2c_adap.dev.parent = &itv->pdev->dev; |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 616 | |
| 617 | IVTV_DEBUG_I2C("setting scl and sda to 1\n"); |
| 618 | ivtv_setscl(itv, 1); |
| 619 | ivtv_setsda(itv, 1); |
| 620 | |
| 621 | if (itv->options.newi2c > 0) |
| 622 | return i2c_add_adapter(&itv->i2c_adap); |
| 623 | else |
| 624 | return i2c_bit_add_bus(&itv->i2c_adap); |
| 625 | } |
| 626 | |
David Miller | bb374b7 | 2007-10-30 21:23:48 -0700 | [diff] [blame] | 627 | void exit_ivtv_i2c(struct ivtv *itv) |
Hans Verkuil | 1a0adaf | 2007-04-27 12:31:25 -0300 | [diff] [blame] | 628 | { |
| 629 | IVTV_DEBUG_I2C("i2c exit\n"); |
| 630 | |
| 631 | i2c_del_adapter(&itv->i2c_adap); |
| 632 | } |