1// SPDX-License-Identifier: GPL-2.0
2// cx231xx IR glue driver
3//
4// Copyright (c) 2010 Mauro Carvalho Chehab <mchehab@kernel.org>
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#include "cx231xx.h"
12#include <linux/slab.h>
13#include <linux/bitrev.h>
14
15#define MODULE_NAME "cx231xx-input"
16
17static int get_key_isdbt(struct IR_i2c *ir, enum rc_proto *protocol,
18			 u32 *pscancode, u8 *toggle)
19{
20	int	rc;
21	u8	cmd, scancode;
22
23	dev_dbg(&ir->rc->dev, "%s\n", __func__);
24
25		/* poll IR chip */
26	rc = i2c_master_recv(ir->c, &cmd, 1);
27	if (rc < 0)
28		return rc;
29	if (rc != 1)
30		return -EIO;
31
32	/* it seems that 0xFE indicates that a button is still hold
33	   down, while 0xff indicates that no button is hold
34	   down. 0xfe sequences are sometimes interrupted by 0xFF */
35
36	if (cmd == 0xff)
37		return 0;
38
39	scancode = bitrev8(cmd);
40
41	dev_dbg(&ir->rc->dev, "cmd %02x, scan = %02x\n", cmd, scancode);
42
43	*protocol = RC_PROTO_OTHER;
44	*pscancode = scancode;
45	*toggle = 0;
46	return 1;
47}
48
49int cx231xx_ir_init(struct cx231xx *dev)
50{
51	struct i2c_board_info info;
52	u8 ir_i2c_bus;
53
54	dev_dbg(dev->dev, "%s\n", __func__);
55
56	/* Only initialize if a rc keycode map is defined */
57	if (!cx231xx_boards[dev->model].rc_map_name)
58		return -ENODEV;
59
60	request_module("ir-kbd-i2c");
61
62	memset(&info, 0, sizeof(struct i2c_board_info));
63	memset(&dev->init_data, 0, sizeof(dev->init_data));
64	dev->init_data.rc_dev = rc_allocate_device(RC_DRIVER_SCANCODE);
65	if (!dev->init_data.rc_dev)
66		return -ENOMEM;
67
68	dev->init_data.name = cx231xx_boards[dev->model].name;
69
70	strscpy(info.type, "ir_video", I2C_NAME_SIZE);
71	info.platform_data = &dev->init_data;
72
73	/*
74	 * Board-dependent values
75	 *
76	 * For now, there's just one type of hardware design using
77	 * an i2c device.
78	 */
79	dev->init_data.get_key = get_key_isdbt;
80	dev->init_data.ir_codes = cx231xx_boards[dev->model].rc_map_name;
81	/* The i2c micro-controller only outputs the cmd part of NEC protocol */
82	dev->init_data.rc_dev->scancode_mask = 0xff;
83	dev->init_data.rc_dev->driver_name = "cx231xx";
84	dev->init_data.type = RC_PROTO_BIT_NEC;
85	info.addr = 0x30;
86
87	/* Load and bind ir-kbd-i2c */
88	ir_i2c_bus = cx231xx_boards[dev->model].ir_i2c_master;
89	dev_dbg(dev->dev, "Trying to bind ir at bus %d, addr 0x%02x\n",
90		ir_i2c_bus, info.addr);
91	dev->ir_i2c_client = i2c_new_client_device(
92		cx231xx_get_i2c_adap(dev, ir_i2c_bus), &info);
93
94	return 0;
95}
96
97void cx231xx_ir_exit(struct cx231xx *dev)
98{
99	i2c_unregister_device(dev->ir_i2c_client);
100	dev->ir_i2c_client = NULL;
101}
102