diff options
Diffstat (limited to 'drivers/leds/leds-cpcap.c')
| -rw-r--r-- | drivers/leds/leds-cpcap.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/drivers/leds/leds-cpcap.c b/drivers/leds/leds-cpcap.c new file mode 100644 index 000000000000..f0f28c442807 --- /dev/null +++ b/drivers/leds/leds-cpcap.c @@ -0,0 +1,239 @@ +/* + * Copyright (c) 2017 Sebastian Reichel <sre@kernel.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 or + * later as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/leds.h> +#include <linux/mfd/motorola-cpcap.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> + +#define CPCAP_LED_NO_CURRENT 0x0001 + +struct cpcap_led_info { + u16 reg; + u16 mask; + u16 limit; + u16 init_mask; + u16 init_val; +}; + +static const struct cpcap_led_info cpcap_led_red = { + .reg = CPCAP_REG_REDC, + .mask = 0x03FF, + .limit = 31, +}; + +static const struct cpcap_led_info cpcap_led_green = { + .reg = CPCAP_REG_GREENC, + .mask = 0x03FF, + .limit = 31, +}; + +static const struct cpcap_led_info cpcap_led_blue = { + .reg = CPCAP_REG_BLUEC, + .mask = 0x03FF, + .limit = 31, +}; + +/* aux display light */ +static const struct cpcap_led_info cpcap_led_adl = { + .reg = CPCAP_REG_ADLC, + .mask = 0x000F, + .limit = 1, + .init_mask = 0x7FFF, + .init_val = 0x5FF0, +}; + +/* camera privacy led */ +static const struct cpcap_led_info cpcap_led_cp = { + .reg = CPCAP_REG_CLEDC, + .mask = 0x0007, + .limit = 1, + .init_mask = 0x03FF, + .init_val = 0x0008, +}; + +struct cpcap_led { + struct led_classdev led; + const struct cpcap_led_info *info; + struct device *dev; + struct regmap *regmap; + struct mutex update_lock; + struct regulator *vdd; + bool powered; + + u32 current_limit; +}; + +static u16 cpcap_led_val(u8 current_limit, u8 duty_cycle) +{ + current_limit &= 0x1f; /* 5 bit */ + duty_cycle &= 0x0f; /* 4 bit */ + + return current_limit << 4 | duty_cycle; +} + +static int cpcap_led_set_power(struct cpcap_led *led, bool status) +{ + int err; + + if (status == led->powered) + return 0; + + if (status) + err = regulator_enable(led->vdd); + else + err = regulator_disable(led->vdd); + + if (err) { + dev_err(led->dev, "regulator failure: %d", err); + return err; + } + + led->powered = status; + + return 0; +} + +static int cpcap_led_set(struct led_classdev *ledc, enum led_brightness value) +{ + struct cpcap_led *led = container_of(ledc, struct cpcap_led, led); + int brightness; + int err; + + mutex_lock(&led->update_lock); + + if (value > LED_OFF) { + err = cpcap_led_set_power(led, true); + if (err) + goto exit; + } + + if (value == LED_OFF) { + /* Avoid HW issue by turning off current before duty cycle */ + err = regmap_update_bits(led->regmap, + led->info->reg, led->info->mask, CPCAP_LED_NO_CURRENT); + if (err) { + dev_err(led->dev, "regmap failed: %d", err); + goto exit; + } + + brightness = cpcap_led_val(value, LED_OFF); + } else { + brightness = cpcap_led_val(value, LED_ON); + } + + err = regmap_update_bits(led->regmap, led->info->reg, led->info->mask, + brightness); + if (err) { + dev_err(led->dev, "regmap failed: %d", err); + goto exit; + } + + if (value == LED_OFF) { + err = cpcap_led_set_power(led, false); + if (err) + goto exit; + } + +exit: + mutex_unlock(&led->update_lock); + return err; +} + +static const struct of_device_id cpcap_led_of_match[] = { + { .compatible = "motorola,cpcap-led-red", .data = &cpcap_led_red }, + { .compatible = "motorola,cpcap-led-green", .data = &cpcap_led_green }, + { .compatible = "motorola,cpcap-led-blue", .data = &cpcap_led_blue }, + { .compatible = "motorola,cpcap-led-adl", .data = &cpcap_led_adl }, + { .compatible = "motorola,cpcap-led-cp", .data = &cpcap_led_cp }, + {}, +}; +MODULE_DEVICE_TABLE(of, cpcap_led_of_match); + +static int cpcap_led_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct cpcap_led *led; + int err; + + match = of_match_device(of_match_ptr(cpcap_led_of_match), &pdev->dev); + if (!match || !match->data) + return -EINVAL; + + led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL); + if (!led) + return -ENOMEM; + platform_set_drvdata(pdev, led); + led->info = match->data; + led->dev = &pdev->dev; + + if (led->info->reg == 0x0000) { + dev_err(led->dev, "Unsupported LED"); + return -ENODEV; + } + + led->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!led->regmap) + return -ENODEV; + + led->vdd = devm_regulator_get(&pdev->dev, "vdd"); + if (IS_ERR(led->vdd)) { + err = PTR_ERR(led->vdd); + dev_err(led->dev, "Couldn't get regulator: %d", err); + return err; + } + + err = device_property_read_string(&pdev->dev, "label", &led->led.name); + if (err) { + dev_err(led->dev, "Couldn't read LED label: %d", err); + return err; + } + + if (led->info->init_mask) { + err = regmap_update_bits(led->regmap, led->info->reg, + led->info->init_mask, led->info->init_val); + if (err) { + dev_err(led->dev, "regmap failed: %d", err); + return err; + } + } + + mutex_init(&led->update_lock); + + led->led.max_brightness = led->info->limit; + led->led.brightness_set_blocking = cpcap_led_set; + err = devm_led_classdev_register(&pdev->dev, &led->led); + if (err) { + dev_err(led->dev, "Couldn't register LED: %d", err); + return err; + } + + return 0; +} + +static struct platform_driver cpcap_led_driver = { + .probe = cpcap_led_probe, + .driver = { + .name = "cpcap-led", + .of_match_table = cpcap_led_of_match, + }, +}; +module_platform_driver(cpcap_led_driver); + +MODULE_DESCRIPTION("CPCAP LED driver"); +MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>"); +MODULE_LICENSE("GPL"); |