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 21 static const struct gpio_led atomisp2_leds[] = { 22 { 23 .name = "atomisp2::camera", 24 .default_state = LEDS_GPIO_DEFSTATE_OFF, 25 }, 26 }; 27 28 static const struct gpio_led_platform_data atomisp2_leds_pdata = { 29 .num_leds = ARRAY_SIZE(atomisp2_leds), 30 .leds = atomisp2_leds, 31 }; 32 33 static 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 41 static 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 49 static const struct dmi_system_id atomisp2_led_systems[] __initconst = { 50 { 51 .matches = { 52 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 53 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T100TA"), 54 }, 55 .driver_data = &asus_t100ta_lookup, 56 }, 57 { 58 .matches = { 59 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 60 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T200TA"), 61 }, 62 .driver_data = &asus_t100ta_lookup, 63 }, 64 { 65 .matches = { 66 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 67 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T100CHI"), 68 }, 69 .driver_data = &asus_t100chi_lookup, 70 }, 71 {} /* Terminating entry */ 72 }; 73 MODULE_DEVICE_TABLE(dmi, atomisp2_led_systems); 74 75 static struct gpiod_lookup_table *gpio_lookup; 76 static struct platform_device *pdev; 77 78 static int __init atomisp2_led_init(void) 79 { 80 const struct dmi_system_id *system; 81 82 system = dmi_first_match(atomisp2_led_systems); 83 if (!system) 84 return -ENODEV; 85 86 gpio_lookup = system->driver_data; 87 gpiod_add_lookup_table(gpio_lookup); 88 89 pdev = platform_device_register_resndata(NULL, 90 DEV_NAME, PLATFORM_DEVID_NONE, 91 NULL, 0, &atomisp2_leds_pdata, 92 sizeof(atomisp2_leds_pdata)); 93 if (IS_ERR(pdev)) 94 gpiod_remove_lookup_table(gpio_lookup); 95 96 return PTR_ERR_OR_ZERO(pdev); 97 } 98 99 static void __exit atomisp2_led_cleanup(void) 100 { 101 platform_device_unregister(pdev); 102 gpiod_remove_lookup_table(gpio_lookup); 103 } 104 105 module_init(atomisp2_led_init); 106 module_exit(atomisp2_led_cleanup); 107 108 /* 109 * The ACPI INIT method from Asus WMI's code on the T100TA and T200TA turns the 110 * LED on (without the WMI interface allowing further control over the LED). 111 * Ensure we are loaded after asus-nb-wmi so that we turn the LED off again. 112 */ 113 MODULE_SOFTDEP("pre: asus_nb_wmi"); 114 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com"); 115 MODULE_DESCRIPTION("Intel atomisp2 camera LED driver"); 116 MODULE_LICENSE("GPL"); 117