linux/drivers/media/video/cx231xx/cx231xx-input.c
<<
>>
Prefs
   1/*
   2  handle cx231xx IR remotes via linux kernel input layer.
   3
   4  Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
   5                Based on em28xx driver
   6
   7                < This is a place holder for IR now.>
   8
   9  This program is free software; you can redistribute it and/or modify
  10  it under the terms of the GNU General Public License as published by
  11  the Free Software Foundation; either version 2 of the License, or
  12  (at your option) any later version.
  13
  14  This program is distributed in the hope that it will be useful,
  15  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  GNU General Public License for more details.
  18
  19  You should have received a copy of the GNU General Public License
  20  along with this program; if not, write to the Free Software
  21  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22 */
  23
  24#include <linux/module.h>
  25#include <linux/init.h>
  26#include <linux/delay.h>
  27#include <linux/interrupt.h>
  28#include <linux/input.h>
  29#include <linux/usb.h>
  30#include <linux/slab.h>
  31
  32#include "cx231xx.h"
  33
  34static unsigned int ir_debug;
  35module_param(ir_debug, int, 0644);
  36MODULE_PARM_DESC(ir_debug, "enable debug messages [IR]");
  37
  38#define MODULE_NAME "cx231xx"
  39
  40#define i2cdprintk(fmt, arg...) \
  41        if (ir_debug) { \
  42                printk(KERN_DEBUG "%s/ir: " fmt, ir->name , ## arg); \
  43        }
  44
  45#define dprintk(fmt, arg...) \
  46        if (ir_debug) { \
  47                printk(KERN_DEBUG "%s/ir: " fmt, ir->name , ## arg); \
  48        }
  49
  50/**********************************************************
  51 Polling structure used by cx231xx IR's
  52 **********************************************************/
  53
  54struct cx231xx_ir_poll_result {
  55        unsigned int toggle_bit:1;
  56        unsigned int read_count:7;
  57        u8 rc_address;
  58        u8 rc_data[4];
  59};
  60
  61struct cx231xx_IR {
  62        struct cx231xx *dev;
  63        struct input_dev *input;
  64        char name[32];
  65        char phys[32];
  66
  67        /* poll external decoder */
  68        int polling;
  69        struct work_struct work;
  70        struct timer_list timer;
  71        unsigned int last_readcount;
  72
  73        int (*get_key) (struct cx231xx_IR *, struct cx231xx_ir_poll_result *);
  74};
  75
  76/**********************************************************
  77 Polling code for cx231xx
  78 **********************************************************/
  79
  80static void cx231xx_ir_handle_key(struct cx231xx_IR *ir)
  81{
  82        int result;
  83        struct cx231xx_ir_poll_result poll_result;
  84
  85        /* read the registers containing the IR status */
  86        result = ir->get_key(ir, &poll_result);
  87        if (result < 0) {
  88                dprintk("ir->get_key() failed %d\n", result);
  89                return;
  90        }
  91
  92        dprintk("ir->get_key result tb=%02x rc=%02x lr=%02x data=%02x\n",
  93                poll_result.toggle_bit, poll_result.read_count,
  94                ir->last_readcount, poll_result.rc_data[0]);
  95
  96        if (poll_result.read_count > 0 &&
  97            poll_result.read_count != ir->last_readcount)
  98                ir_keydown(ir->input,
  99                           poll_result.rc_data[0],
 100                           poll_result.toggle_bit);
 101
 102        if (ir->dev->chip_id == CHIP_ID_EM2874)
 103                /* The em2874 clears the readcount field every time the
 104                   register is read.  The em2860/2880 datasheet says that it
 105                   is supposed to clear the readcount, but it doesn't.  So with
 106                   the em2874, we are looking for a non-zero read count as
 107                   opposed to a readcount that is incrementing */
 108                ir->last_readcount = 0;
 109        else
 110                ir->last_readcount = poll_result.read_count;
 111
 112        }
 113}
 114
 115static void ir_timer(unsigned long data)
 116{
 117        struct cx231xx_IR *ir = (struct cx231xx_IR *)data;
 118
 119        schedule_work(&ir->work);
 120}
 121
 122static void cx231xx_ir_work(struct work_struct *work)
 123{
 124        struct cx231xx_IR *ir = container_of(work, struct cx231xx_IR, work);
 125
 126        cx231xx_ir_handle_key(ir);
 127        mod_timer(&ir->timer, jiffies + msecs_to_jiffies(ir->polling));
 128}
 129
 130void cx231xx_ir_start(struct cx231xx_IR *ir)
 131{
 132        setup_timer(&ir->timer, ir_timer, (unsigned long)ir);
 133        INIT_WORK(&ir->work, cx231xx_ir_work);
 134        schedule_work(&ir->work);
 135}
 136
 137static void cx231xx_ir_stop(struct cx231xx_IR *ir)
 138{
 139        del_timer_sync(&ir->timer);
 140        flush_scheduled_work();
 141}
 142
 143int cx231xx_ir_init(struct cx231xx *dev)
 144{
 145        struct cx231xx_IR *ir;
 146        struct input_dev *input_dev;
 147        u8 ir_config;
 148        int err = -ENOMEM;
 149
 150        if (dev->board.ir_codes == NULL) {
 151                /* No remote control support */
 152                return 0;
 153        }
 154
 155        ir = kzalloc(sizeof(*ir), GFP_KERNEL);
 156        input_dev = input_allocate_device();
 157        if (!ir || !input_dev)
 158                goto err_out_free;
 159
 160        ir->input = input_dev;
 161
 162        /* Setup the proper handler based on the chip */
 163        switch (dev->chip_id) {
 164        default:
 165                printk("Unrecognized cx231xx chip id: IR not supported\n");
 166                goto err_out_free;
 167        }
 168
 169        /* This is how often we ask the chip for IR information */
 170        ir->polling = 100;      /* ms */
 171
 172        /* init input device */
 173        snprintf(ir->name, sizeof(ir->name), "cx231xx IR (%s)", dev->name);
 174
 175        usb_make_path(dev->udev, ir->phys, sizeof(ir->phys));
 176        strlcat(ir->phys, "/input0", sizeof(ir->phys));
 177
 178        input_dev->name = ir->name;
 179        input_dev->phys = ir->phys;
 180        input_dev->id.bustype = BUS_USB;
 181        input_dev->id.version = 1;
 182        input_dev->id.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
 183        input_dev->id.product = le16_to_cpu(dev->udev->descriptor.idProduct);
 184
 185        input_dev->dev.parent = &dev->udev->dev;
 186        /* record handles to ourself */
 187        ir->dev = dev;
 188        dev->ir = ir;
 189
 190        cx231xx_ir_start(ir);
 191
 192        /* all done */
 193        err = __ir_input_register(ir->input, dev->board.ir_codes,
 194                                NULL, MODULE_NAME);
 195        if (err)
 196                goto err_out_stop;
 197
 198        return 0;
 199err_out_stop:
 200        cx231xx_ir_stop(ir);
 201        dev->ir = NULL;
 202err_out_free:
 203        kfree(ir);
 204        return err;
 205}
 206
 207int cx231xx_ir_fini(struct cx231xx *dev)
 208{
 209        struct cx231xx_IR *ir = dev->ir;
 210
 211        /* skip detach on non attached boards */
 212        if (!ir)
 213                return 0;
 214
 215        cx231xx_ir_stop(ir);
 216        ir_input_unregister(ir->input);
 217        kfree(ir);
 218
 219        /* done */
 220        dev->ir = NULL;
 221        return 0;
 222}
 223