1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * Driver for controlling LEDs for cameras connected to the Intel atomisp2 4 * The main purpose of this driver is to turn off LEDs which are on at boot. 5 * 6 * Copyright (C) 2020 Hans de Goede <hdegoede@redhat.com> 7 */ 8 9#include <linux/dmi.h> 10#include <linux/gpio/consumer.h> 11#include <linux/gpio/machine.h> 12#include <linux/leds.h> 13#include <linux/module.h> 14#include <linux/mod_devicetable.h> 15#include <linux/platform_device.h> 16#include <linux/workqueue.h> 17 18/* This must be leds-gpio as the leds-gpio driver binds to the name */ 19#define DEV_NAME "leds-gpio" 20 21static const struct gpio_led atomisp2_leds[] = { 22 { 23 .name = "atomisp2::camera", 24 .default_state = LEDS_GPIO_DEFSTATE_OFF, 25 }, 26}; 27 28static const struct gpio_led_platform_data atomisp2_leds_pdata = { 29 .num_leds = ARRAY_SIZE(atomisp2_leds), 30 .leds = atomisp2_leds, 31}; 32 33static struct gpiod_lookup_table asus_t100ta_lookup = { 34 .dev_id = DEV_NAME, 35 .table = { 36 GPIO_LOOKUP_IDX("INT33FC:02", 8, NULL, 0, GPIO_ACTIVE_HIGH), 37 { } 38 } 39}; 40 41static struct gpiod_lookup_table asus_t100chi_lookup = { 42 .dev_id = DEV_NAME, 43 .table = { 44 GPIO_LOOKUP_IDX("INT33FC:01", 24, NULL, 0, GPIO_ACTIVE_HIGH), 45 { } 46 } 47}; 48 49static const struct dmi_system_id atomisp2_led_systems[] __initconst = { 50 { 51 .matches = { 52 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 53 /* Non exact match to also match T100TAF */ 54 DMI_MATCH(DMI_PRODUCT_NAME, "T100TA"), 55 }, 56 .driver_data = &asus_t100ta_lookup, 57 }, 58 { 59 .matches = { 60 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 61 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T200TA"), 62 }, 63 .driver_data = &asus_t100ta_lookup, 64 }, 65 { 66 .matches = { 67 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 68 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T100CHI"), 69 }, 70 .driver_data = &asus_t100chi_lookup, 71 }, 72 {} /* Terminating entry */ 73}; 74MODULE_DEVICE_TABLE(dmi, atomisp2_led_systems); 75 76static struct gpiod_lookup_table *gpio_lookup; 77static struct platform_device *pdev; 78 79static int __init atomisp2_led_init(void) 80{ 81 const struct dmi_system_id *system; 82 83 system = dmi_first_match(atomisp2_led_systems); 84 if (!system) 85 return -ENODEV; 86 87 gpio_lookup = system->driver_data; 88 gpiod_add_lookup_table(gpio_lookup); 89 90 pdev = platform_device_register_resndata(NULL, 91 DEV_NAME, PLATFORM_DEVID_NONE, 92 NULL, 0, &atomisp2_leds_pdata, 93 sizeof(atomisp2_leds_pdata)); 94 if (IS_ERR(pdev)) 95 gpiod_remove_lookup_table(gpio_lookup); 96 97 return PTR_ERR_OR_ZERO(pdev); 98} 99 100static void __exit atomisp2_led_cleanup(void) 101{ 102 platform_device_unregister(pdev); 103 gpiod_remove_lookup_table(gpio_lookup); 104} 105 106module_init(atomisp2_led_init); 107module_exit(atomisp2_led_cleanup); 108 109/* 110 * The ACPI INIT method from Asus WMI's code on the T100TA and T200TA turns the 111 * LED on (without the WMI interface allowing further control over the LED). 112 * Ensure we are loaded after asus-nb-wmi so that we turn the LED off again. 113 */ 114MODULE_SOFTDEP("pre: asus_nb_wmi"); 115MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com"); 116MODULE_DESCRIPTION("Intel atomisp2 camera LED driver"); 117MODULE_LICENSE("GPL"); 118