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 17 static 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 49 int 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 97 void cx231xx_ir_exit(struct cx231xx *dev) 98 { 99 i2c_unregister_device(dev->ir_i2c_client); 100 dev->ir_i2c_client = NULL; 101 } 102