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 
27 static 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 
60 int 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 
108 void 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