xref: /linux/drivers/media/usb/cx231xx/cx231xx-input.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
1 /*
2  *   cx231xx IR glue driver
3  *
4  *   Copyright (C) 2010 Mauro Carvalho Chehab <mchehab@redhat.com>
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/usb.h>
23 #include <linux/slab.h>
24 
25 #define MODULE_NAME "cx231xx-input"
26 
27 static int get_key_isdbt(struct IR_i2c *ir, u32 *ir_key,
28 			 u32 *ir_raw)
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 =
50 		 ((cmd & 0x01) ? 0x80 : 0) |
51 		 ((cmd & 0x02) ? 0x40 : 0) |
52 		 ((cmd & 0x04) ? 0x20 : 0) |
53 		 ((cmd & 0x08) ? 0x10 : 0) |
54 		 ((cmd & 0x10) ? 0x08 : 0) |
55 		 ((cmd & 0x20) ? 0x04 : 0) |
56 		 ((cmd & 0x40) ? 0x02 : 0) |
57 		 ((cmd & 0x80) ? 0x01 : 0);
58 
59 	dev_dbg(&ir->rc->input_dev->dev, "cmd %02x, scan = %02x\n",
60 		cmd, scancode);
61 
62 	*ir_key = scancode;
63 	*ir_raw = scancode;
64 	return 1;
65 }
66 
67 int cx231xx_ir_init(struct cx231xx *dev)
68 {
69 	struct i2c_board_info info;
70 	u8 ir_i2c_bus;
71 
72 	dev_dbg(&dev->udev->dev, "%s\n", __func__);
73 
74 	/* Only initialize if a rc keycode map is defined */
75 	if (!cx231xx_boards[dev->model].rc_map_name)
76 		return -ENODEV;
77 
78 	request_module("ir-kbd-i2c");
79 
80 	memset(&info, 0, sizeof(struct i2c_board_info));
81 	memset(&dev->init_data, 0, sizeof(dev->init_data));
82 	dev->init_data.rc_dev = rc_allocate_device();
83 	if (!dev->init_data.rc_dev)
84 		return -ENOMEM;
85 
86 	dev->init_data.name = cx231xx_boards[dev->model].name;
87 
88 	strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
89 	info.platform_data = &dev->init_data;
90 
91 	/*
92 	 * Board-dependent values
93 	 *
94 	 * For now, there's just one type of hardware design using
95 	 * an i2c device.
96 	 */
97 	dev->init_data.get_key = get_key_isdbt;
98 	dev->init_data.ir_codes = cx231xx_boards[dev->model].rc_map_name;
99 	/* The i2c micro-controller only outputs the cmd part of NEC protocol */
100 	dev->init_data.rc_dev->scanmask = 0xff;
101 	dev->init_data.rc_dev->driver_name = "cx231xx";
102 	dev->init_data.type = RC_BIT_NEC;
103 	info.addr = 0x30;
104 
105 	/* Load and bind ir-kbd-i2c */
106 	ir_i2c_bus = cx231xx_boards[dev->model].ir_i2c_master;
107 	dev_dbg(&dev->udev->dev, "Trying to bind ir at bus %d, addr 0x%02x\n",
108 		ir_i2c_bus, info.addr);
109 	dev->ir_i2c_client = i2c_new_device(&dev->i2c_bus[ir_i2c_bus].i2c_adap, &info);
110 
111 	return 0;
112 }
113 
114 void cx231xx_ir_exit(struct cx231xx *dev)
115 {
116 	if (dev->ir_i2c_client)
117 		i2c_unregister_device(dev->ir_i2c_client);
118 	dev->ir_i2c_client = NULL;
119 }
120