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/usb.h>
23 #include <linux/slab.h>
24 #include <linux/bitrev.h>
25 
26 #define MODULE_NAME "cx231xx-input"
27 
28 static int get_key_isdbt(struct IR_i2c *ir, enum rc_type *protocol,
29 			 u32 *pscancode, u8 *toggle)
30 {
31 	int	rc;
32 	u8	cmd, scancode;
33 
34 	dev_dbg(&ir->rc->input_dev->dev, "%s\n", __func__);
35 
36 		/* poll IR chip */
37 	rc = i2c_master_recv(ir->c, &cmd, 1);
38 	if (rc < 0)
39 		return rc;
40 	if (rc != 1)
41 		return -EIO;
42 
43 	/* it seems that 0xFE indicates that a button is still hold
44 	   down, while 0xff indicates that no button is hold
45 	   down. 0xfe sequences are sometimes interrupted by 0xFF */
46 
47 	if (cmd == 0xff)
48 		return 0;
49 
50 	scancode = bitrev8(cmd);
51 
52 	dev_dbg(&ir->rc->input_dev->dev, "cmd %02x, scan = %02x\n",
53 		cmd, scancode);
54 
55 	*protocol = RC_TYPE_OTHER;
56 	*pscancode = scancode;
57 	*toggle = 0;
58 	return 1;
59 }
60 
61 int cx231xx_ir_init(struct cx231xx *dev)
62 {
63 	struct i2c_board_info info;
64 	u8 ir_i2c_bus;
65 
66 	dev_dbg(&dev->udev->dev, "%s\n", __func__);
67 
68 	/* Only initialize if a rc keycode map is defined */
69 	if (!cx231xx_boards[dev->model].rc_map_name)
70 		return -ENODEV;
71 
72 	request_module("ir-kbd-i2c");
73 
74 	memset(&info, 0, sizeof(struct i2c_board_info));
75 	memset(&dev->init_data, 0, sizeof(dev->init_data));
76 	dev->init_data.rc_dev = rc_allocate_device();
77 	if (!dev->init_data.rc_dev)
78 		return -ENOMEM;
79 
80 	dev->init_data.name = cx231xx_boards[dev->model].name;
81 
82 	strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
83 	info.platform_data = &dev->init_data;
84 
85 	/*
86 	 * Board-dependent values
87 	 *
88 	 * For now, there's just one type of hardware design using
89 	 * an i2c device.
90 	 */
91 	dev->init_data.get_key = get_key_isdbt;
92 	dev->init_data.ir_codes = cx231xx_boards[dev->model].rc_map_name;
93 	/* The i2c micro-controller only outputs the cmd part of NEC protocol */
94 	dev->init_data.rc_dev->scancode_mask = 0xff;
95 	dev->init_data.rc_dev->driver_name = "cx231xx";
96 	dev->init_data.type = RC_BIT_NEC;
97 	info.addr = 0x30;
98 
99 	/* Load and bind ir-kbd-i2c */
100 	ir_i2c_bus = cx231xx_boards[dev->model].ir_i2c_master;
101 	dev_dbg(&dev->udev->dev, "Trying to bind ir at bus %d, addr 0x%02x\n",
102 		ir_i2c_bus, info.addr);
103 	dev->ir_i2c_client = i2c_new_device(&dev->i2c_bus[ir_i2c_bus].i2c_adap, &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