LXR linux/drivers/media/usb/cx231xx/cx231xx-input.c

   1/*
   2 *   cx231xx IR glue driver
   3 *
   4 *   Copyright (C) 2010 Mauro Carvalho Chehab
   5 *
   6 *   Polaris (cx231xx) has its support for IR's with a design close to MCE.
   7 *   however, a few designs are using an external I2C chip for IR, instead
   8 *   of using the one provided by the chip.
   9 *   This driver provides support for those extra devices
  10 *
  11 *   This program is free software; you can redistribute it and/or
  12 *   modify it under the terms of the GNU General Public License as
  13 *   published by the Free Software Foundation version 2.
  14 *
  15 *   This program is distributed in the hope that it will be useful,
  16 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18 *   General Public License for more details.
  19 */
  20
  21#include "cx231xx.h"
  22#include <linux/slab.h>
  23#include <linux/bitrev.h>
  24
  25#define MODULE_NAME "cx231xx-input"
  26
  27static int get_key_isdbt(struct IR_i2c *ir, enum rc_type *protocol,
  28                         u32 *pscancode, u8 *toggle)
  29{
  30        int     rc;
  31        u8      cmd, scancode;
  32
  33        dev_dbg(&ir->rc->input_dev->dev, "%s\n", __func__);
  34
  35                /* poll IR chip */
  36        rc = i2c_master_recv(ir->c, &cmd, 1);
  37        if (rc < 0)
  38                return rc;
  39        if (rc != 1)
  40                return -EIO;
  41
  42        /* it seems that 0xFE indicates that a button is still hold
  43           down, while 0xff indicates that no button is hold
  44           down. 0xfe sequences are sometimes interrupted by 0xFF */
  45
  46        if (cmd == 0xff)
  47                return 0;
  48
  49        scancode = bitrev8(cmd);
  50
  51        dev_dbg(&ir->rc->input_dev->dev, "cmd %02x, scan = %02x\n",
  52                cmd, scancode);
  53
  54        *protocol = RC_TYPE_OTHER;
  55        *pscancode = scancode;
  56        *toggle = 0;
  57        return 1;
  58}
  59
  60int cx231xx_ir_init(struct cx231xx *dev)
  61{
  62        struct i2c_board_info info;
  63        u8 ir_i2c_bus;
  64
  65        dev_dbg(dev->dev, "%s\n", __func__);
  66
  67        /* Only initialize if a rc keycode map is defined */
  68        if (!cx231xx_boards[dev->model].rc_map_name)
  69                return -ENODEV;
  70
  71        request_module("ir-kbd-i2c");
  72
  73        memset(&info, 0, sizeof(struct i2c_board_info));
  74        memset(&dev->init_data, 0, sizeof(dev->init_data));
  75        dev->init_data.rc_dev = rc_allocate_device();
  76        if (!dev->init_data.rc_dev)
  77                return -ENOMEM;
  78
  79        dev->init_data.name = cx231xx_boards[dev->model].name;
  80
  81        strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
  82        info.platform_data = &dev->init_data;
  83
  84        /*
  85         * Board-dependent values
  86         *
  87         * For now, there's just one type of hardware design using
  88         * an i2c device.
  89         */
  90        dev->init_data.get_key = get_key_isdbt;
  91        dev->init_data.ir_codes = cx231xx_boards[dev->model].rc_map_name;
  92        /* The i2c micro-controller only outputs the cmd part of NEC protocol */
  93        dev->init_data.rc_dev->scancode_mask = 0xff;
  94        dev->init_data.rc_dev->driver_name = "cx231xx";
  95        dev->init_data.type = RC_BIT_NEC;
  96        info.addr = 0x30;
  97
  98        /* Load and bind ir-kbd-i2c */
  99        ir_i2c_bus = cx231xx_boards[dev->model].ir_i2c_master;
 100        dev_dbg(dev->dev, "Trying to bind ir at bus %d, addr 0x%02x\n",
 101                ir_i2c_bus, info.addr);
 102        dev->ir_i2c_client = i2c_new_device(
 103                cx231xx_get_i2c_adap(dev, ir_i2c_bus), &info);
 104
 105        return 0;
 106}
 107
 108void cx231xx_ir_exit(struct cx231xx *dev)
 109{
 110        if (dev->ir_i2c_client)
 111                i2c_unregister_device(dev->ir_i2c_client);
 112        dev->ir_i2c_client = NULL;
 113}
 114