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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Driver for Samsung Q10 and related laptops: controls the backlight4 *5 * Copyright (c) 2011 Frederick van der Wyck <fvanderwyck@gmail.com>6 */7 8#include <linux/module.h>9#include <linux/kernel.h>10#include <linux/init.h>11#include <linux/platform_device.h>12#include <linux/backlight.h>13#include <linux/dmi.h>14#include <linux/acpi.h>15 16#define SAMSUNGQ10_BL_MAX_INTENSITY 717 18static acpi_handle ec_handle;19 20static bool force;21module_param(force, bool, 0);22MODULE_PARM_DESC(force,23 "Disable the DMI check and force the driver to be loaded");24 25static int samsungq10_bl_set_intensity(struct backlight_device *bd)26{27 28 acpi_status status;29 int i;30 31 for (i = 0; i < SAMSUNGQ10_BL_MAX_INTENSITY; i++) {32 status = acpi_evaluate_object(ec_handle, "_Q63", NULL, NULL);33 if (ACPI_FAILURE(status))34 return -EIO;35 }36 for (i = 0; i < bd->props.brightness; i++) {37 status = acpi_evaluate_object(ec_handle, "_Q64", NULL, NULL);38 if (ACPI_FAILURE(status))39 return -EIO;40 }41 42 return 0;43}44 45static const struct backlight_ops samsungq10_bl_ops = {46 .update_status = samsungq10_bl_set_intensity,47};48 49static int samsungq10_probe(struct platform_device *pdev)50{51 52 struct backlight_properties props;53 struct backlight_device *bd;54 55 memset(&props, 0, sizeof(struct backlight_properties));56 props.type = BACKLIGHT_PLATFORM;57 props.max_brightness = SAMSUNGQ10_BL_MAX_INTENSITY;58 bd = backlight_device_register("samsung", &pdev->dev, NULL,59 &samsungq10_bl_ops, &props);60 if (IS_ERR(bd))61 return PTR_ERR(bd);62 63 platform_set_drvdata(pdev, bd);64 65 return 0;66}67 68static void samsungq10_remove(struct platform_device *pdev)69{70 71 struct backlight_device *bd = platform_get_drvdata(pdev);72 73 backlight_device_unregister(bd);74}75 76static struct platform_driver samsungq10_driver = {77 .driver = {78 .name = KBUILD_MODNAME,79 },80 .probe = samsungq10_probe,81 .remove_new = samsungq10_remove,82};83 84static struct platform_device *samsungq10_device;85 86static int __init dmi_check_callback(const struct dmi_system_id *id)87{88 printk(KERN_INFO KBUILD_MODNAME ": found model '%s'\n", id->ident);89 return 1;90}91 92static const struct dmi_system_id samsungq10_dmi_table[] __initconst = {93 {94 .ident = "Samsung Q10",95 .matches = {96 DMI_MATCH(DMI_SYS_VENDOR, "Samsung"),97 DMI_MATCH(DMI_PRODUCT_NAME, "SQ10"),98 },99 .callback = dmi_check_callback,100 },101 {102 .ident = "Samsung Q20",103 .matches = {104 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG Electronics"),105 DMI_MATCH(DMI_PRODUCT_NAME, "SENS Q20"),106 },107 .callback = dmi_check_callback,108 },109 {110 .ident = "Samsung Q25",111 .matches = {112 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG Electronics"),113 DMI_MATCH(DMI_PRODUCT_NAME, "NQ25"),114 },115 .callback = dmi_check_callback,116 },117 {118 .ident = "Dell Latitude X200",119 .matches = {120 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),121 DMI_MATCH(DMI_PRODUCT_NAME, "X200"),122 },123 .callback = dmi_check_callback,124 },125 { },126};127MODULE_DEVICE_TABLE(dmi, samsungq10_dmi_table);128 129static int __init samsungq10_init(void)130{131 if (!force && !dmi_check_system(samsungq10_dmi_table))132 return -ENODEV;133 134 ec_handle = ec_get_handle();135 136 if (!ec_handle)137 return -ENODEV;138 139 samsungq10_device = platform_create_bundle(&samsungq10_driver,140 samsungq10_probe,141 NULL, 0, NULL, 0);142 143 return PTR_ERR_OR_ZERO(samsungq10_device);144}145 146static void __exit samsungq10_exit(void)147{148 platform_device_unregister(samsungq10_device);149 platform_driver_unregister(&samsungq10_driver);150}151 152module_init(samsungq10_init);153module_exit(samsungq10_exit);154 155MODULE_AUTHOR("Frederick van der Wyck <fvanderwyck@gmail.com>");156MODULE_DESCRIPTION("Samsung Q10 Driver");157MODULE_LICENSE("GPL");158