drivers/media/video/cx23885/cx23885-input.c

   1 /*
   2  *  Driver for the Conexant CX23885/7/8 PCIe bridge
   3  *
   4  *  Infrared remote control input device
   5  *
   6  *  Most of this file is
   7  *
   8  *  Copyright (C) 2009  Andy Walls <awalls@radix.net>
   9  *
  10  *  However, the cx23885_input_{init,fini} functions contained herein are
  11  *  derived from Linux kernel files linux/media/video/.../...-input.c marked as:
  12  *
  13  *  Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
  14  *  Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it>
  15  *                     Markus Rechberger <mrechberger@gmail.com>
  16  *                     Mauro Carvalho Chehab <mchehab@infradead.org>
  17  *                     Sascha Sommer <saschasommer@freenet.de>
  18  *  Copyright (C) 2004, 2005 Chris Pascoe
  19  *  Copyright (C) 2003, 2004 Gerd Knorr
  20  *  Copyright (C) 2003 Pavel Machek
  21  *
  22  *  This program is free software; you can redistribute it and/or
  23  *  modify it under the terms of the GNU General Public License
  24  *  as published by the Free Software Foundation; either version 2
  25  *  of the License, or (at your option) any later version.
  26  *
  27  *  This program is distributed in the hope that it will be useful,
  28  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  29  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  30  *  GNU General Public License for more details.
  31  *
  32  *  You should have received a copy of the GNU General Public License
  33  *  along with this program; if not, write to the Free Software
  34  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  35  *  02110-1301, USA.
  36  */
  37
  38 #include <linux/input.h>
  39 #include <media/ir-common.h>
  40 #include <media/v4l2-subdev.h>
  41
  42 #include "cx23885.h"
  43
  44 #define RC5_BITS                14
  45 #define RC5_HALF_BITS           (2*RC5_BITS)
  46 #define RC5_HALF_BITS_MASK      ((1 << RC5_HALF_BITS) - 1)
  47
  48 #define RC5_START_BITS_NORMAL   0x3 /* Command range  0 -  63 */
  49 #define RC5_START_BITS_EXTENDED 0x2 /* Command range 64 - 127 */
  50
  51 #define RC5_EXTENDED_COMMAND_OFFSET     64
  52
  53 static inline unsigned int rc5_command(u32 rc5_baseband)
  54 {
  55         return RC5_INSTR(rc5_baseband) +
  56                 ((RC5_START(rc5_baseband) == RC5_START_BITS_EXTENDED)
  57                         ? RC5_EXTENDED_COMMAND_OFFSET : 0);
  58 }
  59
  60 static void cx23885_input_process_raw_rc5(struct cx23885_dev *dev)
  61 {
  62         struct card_ir *ir_input = dev->ir_input;
  63         unsigned int code, command;
  64         u32 rc5;
  65
  66         /* Ignore codes that are too short to be valid RC-5 */
  67         if (ir_input->last_bit < (RC5_HALF_BITS - 1))
  68                 return;
  69
  70         /* The library has the manchester coding backwards; XOR to adapt. */
  71         code = (ir_input->code & RC5_HALF_BITS_MASK) ^ RC5_HALF_BITS_MASK;
  72         rc5 = ir_rc5_decode(code);
  73
  74         switch (RC5_START(rc5)) {
  75         case RC5_START_BITS_NORMAL:
  76                 break;
  77         case RC5_START_BITS_EXTENDED:
  78                 /* Don't allow if the remote only emits standard commands */
  79                 if (ir_input->start == RC5_START_BITS_NORMAL)
  80                         return;
  81                 break;
  82         default:
  83                 return;
  84         }
  85
  86         if (ir_input->addr != RC5_ADDR(rc5))
  87                 return;
  88
  89         /* Don't generate a keypress for RC-5 auto-repeated keypresses */
  90         command = rc5_command(rc5);
  91         if (RC5_TOGGLE(rc5) != RC5_TOGGLE(ir_input->last_rc5) ||
  92             command != rc5_command(ir_input->last_rc5) ||
  93             /* Catch T == 0, CMD == 0 (e.g. '0') as first keypress after init */
  94             RC5_START(ir_input->last_rc5) == 0) {
  95                 /* This keypress is differnet: not an auto repeat */
  96                 ir_input_nokey(ir_input->dev, &ir_input->ir);
  97                 ir_input_keydown(ir_input->dev, &ir_input->ir, command);
  98         }
  99         ir_input->last_rc5 = rc5;
 100
 101         /* Schedule when we should do the key up event: ir_input_nokey() */
 102         mod_timer(&ir_input->timer_keyup,
 103                   jiffies + msecs_to_jiffies(ir_input->rc5_key_timeout));
 104 }
 105
 106 static void cx23885_input_next_pulse_width_rc5(struct cx23885_dev *dev,
 107                                                u32 ns_pulse)
 108 {
 109         const int rc5_quarterbit_ns = 444444; /* 32 cycles/36 kHz/2 = 444 us */
 110         struct card_ir *ir_input = dev->ir_input;
 111         int i, level, quarterbits, halfbits;
 112
 113         if (!ir_input->active) {
 114                 ir_input->active = 1;
 115                 /* assume an initial space that we may not detect or measure */
 116                 ir_input->code = 0;
 117                 ir_input->last_bit = 0;
 118         }
 119
 120         if (ns_pulse == V4L2_SUBDEV_IR_PULSE_RX_SEQ_END) {
 121                 ir_input->last_bit++; /* Account for the final space */
 122                 ir_input->active = 0;
 123                 cx23885_input_process_raw_rc5(dev);
 124                 return;
 125         }
 126
 127         level = (ns_pulse & V4L2_SUBDEV_IR_PULSE_LEVEL_MASK) ? 1 : 0;
 128
 129         /* Skip any leading space to sync to the start bit */
 130         if (ir_input->last_bit == 0 && level == 0)
 131                 return;
 132
 133         /*
 134          * With valid RC-5 we can get up to two consecutive half-bits in a
 135          * single pulse measurment.  Experiments have shown that the duration
 136          * of a half-bit can vary.  Make sure we always end up with an even
 137          * number of quarter bits at the same level (mark or space).
 138          */
 139         ns_pulse &= V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS;
 140         quarterbits = ns_pulse / rc5_quarterbit_ns;
 141         if (quarterbits & 1)
 142                 quarterbits++;
 143         halfbits = quarterbits / 2;
 144
 145         for (i = 0; i < halfbits; i++) {
 146                 ir_input->last_bit++;
 147                 ir_input->code |= (level << ir_input->last_bit);
 148
 149                 if (ir_input->last_bit >= RC5_HALF_BITS-1) {
 150                         ir_input->active = 0;
 151                         cx23885_input_process_raw_rc5(dev);
 152                         /*
 153                          * If level is 1, a leading mark is invalid for RC5.
 154                          * If level is 0, we scan past extra intial space.
 155                          * Either way we don't want to reactivate collecting
 156                          * marks or spaces here with any left over half-bits.
 157                          */
 158                         break;
 159                 }
 160         }
 161 }
 162
 163 static void cx23885_input_process_pulse_widths_rc5(struct cx23885_dev *dev,
 164                                                    bool add_eom)
 165 {
 166         struct card_ir *ir_input = dev->ir_input;
 167         struct ir_input_state *ir_input_state = &ir_input->ir;
 168
 169         u32 ns_pulse[RC5_HALF_BITS+1];
 170         ssize_t num = 0;
 171         int count, i;
 172
 173         do {
 174                 v4l2_subdev_call(dev->sd_ir, ir, rx_read, (u8 *) ns_pulse,
 175                                  sizeof(ns_pulse), &num);
 176
 177                 count = num / sizeof(u32);
 178
 179                 /* Append an end of Rx seq, if the caller requested */
 180                 if (add_eom && count < ARRAY_SIZE(ns_pulse)) {
 181                         ns_pulse[count] = V4L2_SUBDEV_IR_PULSE_RX_SEQ_END;
 182                         count++;
 183                 }
 184
 185                 /* Just drain the Rx FIFO, if we're called, but not RC-5 */
 186                 if (ir_input_state->ir_type != IR_TYPE_RC5)
 187                         continue;
 188
 189                 for (i = 0; i < count; i++)
 190                         cx23885_input_next_pulse_width_rc5(dev, ns_pulse[i]);
 191         } while (num != 0);
 192 }
 193
 194 void cx23885_input_rx_work_handler(struct cx23885_dev *dev, u32 events)
 195 {
 196         struct v4l2_subdev_ir_parameters params;
 197         int overrun, data_available;
 198
 199         if (dev->sd_ir == NULL || events == 0)
 200                 return;
 201
 202         switch (dev->board) {
 203         case CX23885_BOARD_HAUPPAUGE_HVR1850:
 204         case CX23885_BOARD_HAUPPAUGE_HVR1290:
 205                 /*
 206                  * The only board we handle right now.  However other boards
 207                  * using the CX2388x integrated IR controller should be similar
 208                  */
 209                 break;
 210         default:
 211                 return;
 212         }
 213
 214         overrun = events & (V4L2_SUBDEV_IR_RX_SW_FIFO_OVERRUN |
 215                             V4L2_SUBDEV_IR_RX_HW_FIFO_OVERRUN);
 216
 217         data_available = events & (V4L2_SUBDEV_IR_RX_END_OF_RX_DETECTED |
 218                                    V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ);
 219
 220         if (overrun) {
 221                 /* If there was a FIFO overrun, stop the device */
 222                 v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
 223                 params.enable = false;
 224                 /* Mitigate race with cx23885_input_ir_stop() */
 225                 params.shutdown = atomic_read(&dev->ir_input_stopping);
 226                 v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
 227         }
 228
 229         if (data_available)
 230                 cx23885_input_process_pulse_widths_rc5(dev, overrun);
 231
 232         if (overrun) {
 233                 /* If there was a FIFO overrun, clear & restart the device */
 234                 params.enable = true;
 235                 /* Mitigate race with cx23885_input_ir_stop() */
 236                 params.shutdown = atomic_read(&dev->ir_input_stopping);
 237                 v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
 238         }
 239 }
 240
 241 static void cx23885_input_ir_start(struct cx23885_dev *dev)
 242 {
 243         struct card_ir *ir_input = dev->ir_input;
 244         struct ir_input_state *ir_input_state = &ir_input->ir;
 245         struct v4l2_subdev_ir_parameters params;
 246
 247         if (dev->sd_ir == NULL)
 248                 return;
 249
 250         atomic_set(&dev->ir_input_stopping, 0);
 251
 252         /* keyup timer set up, if needed */
 253         switch (dev->board) {
 254         case CX23885_BOARD_HAUPPAUGE_HVR1850:
 255         case CX23885_BOARD_HAUPPAUGE_HVR1290:
 256                 setup_timer(&ir_input->timer_keyup,
 257                             ir_rc5_timer_keyup, /* Not actually RC-5 specific */
 258                             (unsigned long) ir_input);
 259                 if (ir_input_state->ir_type == IR_TYPE_RC5) {
 260                         /*
 261                          * RC-5 repeats a held key every
 262                          * 64 bits * (2 * 32/36000) sec/bit = 113.778 ms
 263                          */
 264                         ir_input->rc5_key_timeout = 115;
 265                 }
 266                 break;
 267         }
 268
 269         v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
 270         switch (dev->board) {
 271         case CX23885_BOARD_HAUPPAUGE_HVR1850:
 272         case CX23885_BOARD_HAUPPAUGE_HVR1290:
 273                 /*
 274                  * The IR controller on this board only returns pulse widths.
 275                  * Any other mode setting will fail to set up the device.
 276                 */
 277                 params.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
 278                 params.enable = true;
 279                 params.interrupt_enable = true;
 280                 params.shutdown = false;
 281
 282                 /* Setup for baseband compatible with both RC-5 and RC-6A */
 283                 params.modulation = false;
 284                 /* RC-5:  2,222,222 ns = 1/36 kHz * 32 cycles * 2 marks * 1.25*/
 285                 /* RC-6A: 3,333,333 ns = 1/36 kHz * 16 cycles * 6 marks * 1.25*/
 286                 params.max_pulse_width = 3333333; /* ns */
 287                 /* RC-5:    666,667 ns = 1/36 kHz * 32 cycles * 1 mark * 0.75 */
 288                 /* RC-6A:   333,333 ns = 1/36 kHz * 16 cycles * 1 mark * 0.75 */
 289                 params.noise_filter_min_width = 333333; /* ns */
 290                 /*
 291                  * This board has inverted receive sense:
 292                  * mark is received as low logic level;
 293                  * falling edges are detected as rising edges; etc.
 294                  */
 295                 params.invert = true;
 296                 break;
 297         }
 298         v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
 299 }
 300
 301 static void cx23885_input_ir_stop(struct cx23885_dev *dev)
 302 {
 303         struct card_ir *ir_input = dev->ir_input;
 304         struct v4l2_subdev_ir_parameters params;
 305
 306         if (dev->sd_ir == NULL)
 307                 return;
 308
 309         /*
 310          * Stop the sd_ir subdevice from generating notifications and
 311          * scheduling work.
 312          * It is shutdown this way in order to mitigate a race with
 313          * cx23885_input_rx_work_handler() in the overrun case, which could
 314          * re-enable the subdevice.
 315          */
 316         atomic_set(&dev->ir_input_stopping, 1);
 317         v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
 318         while (params.shutdown == false) {
 319                 params.enable = false;
 320                 params.interrupt_enable = false;
 321                 params.shutdown = true;
 322                 v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
 323                 v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
 324         }
 325
 326         flush_scheduled_work();
 327
 328         switch (dev->board) {
 329         case CX23885_BOARD_HAUPPAUGE_HVR1850:
 330         case CX23885_BOARD_HAUPPAUGE_HVR1290:
 331                 del_timer_sync(&ir_input->timer_keyup);
 332                 break;
 333         }
 334 }
 335
 336 int cx23885_input_init(struct cx23885_dev *dev)
 337 {
 338         struct card_ir *ir;
 339         struct input_dev *input_dev;
 340         struct ir_scancode_table *ir_codes = NULL;
 341         int ir_type, ir_addr, ir_start;
 342         int ret;
 343
 344         /*
 345          * If the IR device (hardware registers, chip, GPIO lines, etc.) isn't
 346          * encapsulated in a v4l2_subdev, then I'm not going to deal with it.
 347          */
 348         if (dev->sd_ir == NULL)
 349                 return -ENODEV;
 350
 351         switch (dev->board) {
 352         case CX23885_BOARD_HAUPPAUGE_HVR1850:
 353         case CX23885_BOARD_HAUPPAUGE_HVR1290:
 354                 /* Parameters for the grey Hauppauge remote for the HVR-1850 */
 355                 ir_codes = &ir_codes_hauppauge_new_table;
 356                 ir_type = IR_TYPE_RC5;
 357                 ir_addr = 0x1e; /* RC-5 system bits emitted by the remote */
 358                 ir_start = RC5_START_BITS_NORMAL; /* A basic RC-5 remote */
 359                 break;
 360         }
 361         if (ir_codes == NULL)
 362                 return -ENODEV;
 363
 364         ir = kzalloc(sizeof(*ir), GFP_KERNEL);
 365         input_dev = input_allocate_device();
 366         if (!ir || !input_dev) {
 367                 ret = -ENOMEM;
 368                 goto err_out_free;
 369         }
 370
 371         ir->dev = input_dev;
 372         ir->addr = ir_addr;
 373         ir->start = ir_start;
 374
 375         /* init input device */
 376         snprintf(ir->name, sizeof(ir->name), "cx23885 IR (%s)",
 377                  cx23885_boards[dev->board].name);
 378         snprintf(ir->phys, sizeof(ir->phys), "pci-%s/ir0", pci_name(dev->pci));
 379
 380         ret = ir_input_init(input_dev, &ir->ir, ir_type);
 381         if (ret < 0)
 382                 goto err_out_free;
 383
 384         input_dev->name = ir->name;
 385         input_dev->phys = ir->phys;
 386         input_dev->id.bustype = BUS_PCI;
 387         input_dev->id.version = 1;
 388         if (dev->pci->subsystem_vendor) {
 389                 input_dev->id.vendor  = dev->pci->subsystem_vendor;
 390                 input_dev->id.product = dev->pci->subsystem_device;
 391         } else {
 392                 input_dev->id.vendor  = dev->pci->vendor;
 393                 input_dev->id.product = dev->pci->device;
 394         }
 395         input_dev->dev.parent = &dev->pci->dev;
 396
 397         dev->ir_input = ir;
 398         cx23885_input_ir_start(dev);
 399
 400         ret = ir_input_register(ir->dev, ir_codes, NULL);
 401         if (ret)
 402                 goto err_out_stop;
 403
 404         return 0;
 405
 406 err_out_stop:
 407         cx23885_input_ir_stop(dev);
 408         dev->ir_input = NULL;
 409 err_out_free:
 410         kfree(ir);
 411         return ret;
 412 }
 413
 414 void cx23885_input_fini(struct cx23885_dev *dev)
 415 {
 416         /* Always stop the IR hardware from generating interrupts */
 417         cx23885_input_ir_stop(dev);
 418
 419         if (dev->ir_input == NULL)
 420                 return;
 421         ir_input_unregister(dev->ir_input->dev);
 422         kfree(dev->ir_input);
 423         dev->ir_input = NULL;
 424 }