linux/linux-5.4.31/drivers/media/usb/cx231xx/cx231xx-input.c

103 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
// cx231xx IR glue driver
//
// Copyright (c) 2010 Mauro Carvalho Chehab <mchehab@kernel.org>
//
// Polaris (cx231xx) has its support for IR's with a design close to MCE.
// however, a few designs are using an external I2C chip for IR, instead
// of using the one provided by the chip.
// This driver provides support for those extra devices
#include "cx231xx.h"
#include <linux/slab.h>
#include <linux/bitrev.h>
#define MODULE_NAME "cx231xx-input"
static int get_key_isdbt(struct IR_i2c *ir, enum rc_proto *protocol,
u32 *pscancode, u8 *toggle)
{
int rc;
u8 cmd, scancode;
dev_dbg(&ir->rc->dev, "%s\n", __func__);
/* poll IR chip */
rc = i2c_master_recv(ir->c, &cmd, 1);
if (rc < 0)
return rc;
if (rc != 1)
return -EIO;
/* it seems that 0xFE indicates that a button is still hold
down, while 0xff indicates that no button is hold
down. 0xfe sequences are sometimes interrupted by 0xFF */
if (cmd == 0xff)
return 0;
scancode = bitrev8(cmd);
dev_dbg(&ir->rc->dev, "cmd %02x, scan = %02x\n", cmd, scancode);
*protocol = RC_PROTO_OTHER;
*pscancode = scancode;
*toggle = 0;
return 1;
}
int cx231xx_ir_init(struct cx231xx *dev)
{
struct i2c_board_info info;
u8 ir_i2c_bus;
dev_dbg(dev->dev, "%s\n", __func__);
/* Only initialize if a rc keycode map is defined */
if (!cx231xx_boards[dev->model].rc_map_name)
return -ENODEV;
request_module("ir-kbd-i2c");
memset(&info, 0, sizeof(struct i2c_board_info));
memset(&dev->init_data, 0, sizeof(dev->init_data));
dev->init_data.rc_dev = rc_allocate_device(RC_DRIVER_SCANCODE);
if (!dev->init_data.rc_dev)
return -ENOMEM;
dev->init_data.name = cx231xx_boards[dev->model].name;
strscpy(info.type, "ir_video", I2C_NAME_SIZE);
info.platform_data = &dev->init_data;
/*
* Board-dependent values
*
* For now, there's just one type of hardware design using
* an i2c device.
*/
dev->init_data.get_key = get_key_isdbt;
dev->init_data.ir_codes = cx231xx_boards[dev->model].rc_map_name;
/* The i2c micro-controller only outputs the cmd part of NEC protocol */
dev->init_data.rc_dev->scancode_mask = 0xff;
dev->init_data.rc_dev->driver_name = "cx231xx";
dev->init_data.type = RC_PROTO_BIT_NEC;
info.addr = 0x30;
/* Load and bind ir-kbd-i2c */
ir_i2c_bus = cx231xx_boards[dev->model].ir_i2c_master;
dev_dbg(dev->dev, "Trying to bind ir at bus %d, addr 0x%02x\n",
ir_i2c_bus, info.addr);
dev->ir_i2c_client = i2c_new_device(
cx231xx_get_i2c_adap(dev, ir_i2c_bus), &info);
return 0;
}
void cx231xx_ir_exit(struct cx231xx *dev)
{
if (dev->ir_i2c_client)
i2c_unregister_device(dev->ir_i2c_client);
dev->ir_i2c_client = NULL;
}