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1// SPDX-License-Identifier: GPL-2.0+2 3#include <linux/leds.h>4#include <linux/module.h>5#include <linux/platform_device.h>6#include <linux/regmap.h>7 8#define A500_EC_LED_DELAY_USEC (100 * 1000)9 10enum {11 REG_RESET_LEDS = 0x40,12 REG_POWER_LED_ON = 0x42,13 REG_CHARGE_LED_ON = 0x43,14 REG_ANDROID_LEDS_OFF = 0x5a,15};16 17struct a500_led {18 struct led_classdev cdev;19 const struct reg_sequence *enable_seq;20 struct a500_led *other;21 struct regmap *rmap;22};23 24static const struct reg_sequence a500_ec_leds_reset_seq[] = {25 REG_SEQ(REG_RESET_LEDS, 0x0, A500_EC_LED_DELAY_USEC),26 REG_SEQ(REG_ANDROID_LEDS_OFF, 0x0, A500_EC_LED_DELAY_USEC),27};28 29static const struct reg_sequence a500_ec_white_led_enable_seq[] = {30 REG_SEQ(REG_POWER_LED_ON, 0x0, A500_EC_LED_DELAY_USEC),31};32 33static const struct reg_sequence a500_ec_orange_led_enable_seq[] = {34 REG_SEQ(REG_CHARGE_LED_ON, 0x0, A500_EC_LED_DELAY_USEC),35};36 37static int a500_ec_led_brightness_set(struct led_classdev *led_cdev,38 enum led_brightness value)39{40 struct a500_led *led = container_of(led_cdev, struct a500_led, cdev);41 struct reg_sequence control_seq[2];42 unsigned int num_regs = 1;43 44 if (value) {45 control_seq[0] = led->enable_seq[0];46 } else {47 /*48 * There is no separate controls which can disable LEDs49 * individually, there is only RESET_LEDS command that turns50 * off both LEDs.51 *52 * RESET_LEDS turns off both LEDs, thus restore other LED if53 * it's turned ON.54 */55 if (led->other->cdev.brightness)56 num_regs = 2;57 58 control_seq[0] = a500_ec_leds_reset_seq[0];59 control_seq[1] = led->other->enable_seq[0];60 }61 62 return regmap_multi_reg_write(led->rmap, control_seq, num_regs);63}64 65static int a500_ec_leds_probe(struct platform_device *pdev)66{67 struct a500_led *white_led, *orange_led;68 struct regmap *rmap;69 int err;70 71 rmap = dev_get_regmap(pdev->dev.parent, "KB930");72 if (!rmap)73 return -EINVAL;74 75 /* reset and turn off LEDs */76 regmap_multi_reg_write(rmap, a500_ec_leds_reset_seq, 2);77 78 white_led = devm_kzalloc(&pdev->dev, sizeof(*white_led), GFP_KERNEL);79 if (!white_led)80 return -ENOMEM;81 82 white_led->cdev.name = "power:white";83 white_led->cdev.brightness_set_blocking = a500_ec_led_brightness_set;84 white_led->cdev.flags = LED_CORE_SUSPENDRESUME;85 white_led->cdev.max_brightness = 1;86 white_led->enable_seq = a500_ec_white_led_enable_seq;87 white_led->rmap = rmap;88 89 orange_led = devm_kzalloc(&pdev->dev, sizeof(*orange_led), GFP_KERNEL);90 if (!orange_led)91 return -ENOMEM;92 93 orange_led->cdev.name = "power:orange";94 orange_led->cdev.brightness_set_blocking = a500_ec_led_brightness_set;95 orange_led->cdev.flags = LED_CORE_SUSPENDRESUME;96 orange_led->cdev.max_brightness = 1;97 orange_led->enable_seq = a500_ec_orange_led_enable_seq;98 orange_led->rmap = rmap;99 100 white_led->other = orange_led;101 orange_led->other = white_led;102 103 err = devm_led_classdev_register(&pdev->dev, &white_led->cdev);104 if (err) {105 dev_err(&pdev->dev, "failed to register white LED\n");106 return err;107 }108 109 err = devm_led_classdev_register(&pdev->dev, &orange_led->cdev);110 if (err) {111 dev_err(&pdev->dev, "failed to register orange LED\n");112 return err;113 }114 115 return 0;116}117 118static struct platform_driver a500_ec_leds_driver = {119 .driver = {120 .name = "acer-a500-iconia-leds",121 },122 .probe = a500_ec_leds_probe,123};124module_platform_driver(a500_ec_leds_driver);125 126MODULE_DESCRIPTION("LED driver for Acer Iconia Tab A500 Power Button");127MODULE_AUTHOR("Dmitry Osipenko <digetx@gmail.com>");128MODULE_ALIAS("platform:acer-a500-iconia-leds");129MODULE_LICENSE("GPL");130