cx231xx-input.c

  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}