From: Sean Wang <sean.wang@xxxxxxxxxxxx> MT6323 PMIC is a multi-function device that includes LED function. It allows attaching upto 4 LEDs which can either be on, off or dimmed and/or blinked with the the controller. Signed-off-by: Sean Wang <sean.wang@xxxxxxxxxxxx> --- drivers/leds/Kconfig | 8 + drivers/leds/Makefile | 1 + drivers/leds/leds-mt6323.c | 391 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 400 insertions(+) create mode 100644 drivers/leds/leds-mt6323.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index c621cbb..30095fc 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -117,6 +117,14 @@ config LEDS_MIKROTIK_RB532 This option enables support for the so called "User LED" of Mikrotik's Routerboard 532. +config LEDS_MT6323 + tristate "LED Support for Mediatek MT6323 PMIC" + depends on LEDS_CLASS + depends on MFD_MT6397 + help + This option enables support for on-chip LED drivers found on + Mediatek MT6323 PMIC. + config LEDS_S3C24XX tristate "LED Support for Samsung S3C24XX GPIO LEDs" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 6b82737..4feb332 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -72,6 +72,7 @@ obj-$(CONFIG_LEDS_IS31FL32XX) += leds-is31fl32xx.o obj-$(CONFIG_LEDS_PM8058) += leds-pm8058.o obj-$(CONFIG_LEDS_MLXCPLD) += leds-mlxcpld.o obj-$(CONFIG_LEDS_NIC78BX) += leds-nic78bx.o +obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o # LED SPI Drivers obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o diff --git a/drivers/leds/leds-mt6323.c b/drivers/leds/leds-mt6323.c new file mode 100644 index 0000000..de3006d --- /dev/null +++ b/drivers/leds/leds-mt6323.c @@ -0,0 +1,391 @@ +/* + * LED driver for Mediatek MT6323 PMIC + * + * Copyright (C) 2017 Sean Wang <sean.wang@xxxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * 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/kernel.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/leds.h> +#include <linux/regmap.h> +#include <linux/mfd/mt6397/core.h> +#include <linux/mfd/mt6323/registers.h> +#include <linux/module.h> + +/* Register to enable 32K clock common for LED device */ +#define MTK_MT6323_TOP_CKPDN0 0x0102 +#define RG_DRV_32K_CK_PDN BIT(11) +#define RG_DRV_32K_CK_PDN_MASK BIT(11) + +/* Register to enable individual clock for LED device */ +#define MTK_MT6323_TOP_CKPDN2 0x010E +#define RG_ISINK_CK_PDN(i) BIT(i) +#define RG_ISINK_CK_PDN_MASK(i) BIT(i) + +/* Register to select clock source */ +#define MTK_MT6323_TOP_CKCON1 0x0126 +#define RG_ISINK_CK_SEL_MASK(i) (BIT(10) << (i)) + +/* Register to setup the duty cycle of the blink */ +#define MTK_MT6323_ISINK_CON0(i) (0x0330 + 0x8 * (i)) +#define ISINK_DIM_DUTY(i) (((i) << 8) & GENMASK(12, 8)) +#define ISINK_DIM_DUTY_MASK GENMASK(12, 8) + +/* Register to setup the period of the blink */ +#define MTK_MT6323_ISINK_CON1(i) (0x0332 + 0x8 * (i)) +#define ISINK_DIM_FSEL(i) ((i) & GENMASK(15, 0)) +#define ISINK_DIM_FSEL_MASK GENMASK(15, 0) + +/* Register to control the brightness */ +#define MTK_MT6323_ISINK_CON2(i) (0x0334 + 0x8 * (i)) +#define ISINK_CH_STEP(i) (((i) << 12) & GENMASK(14, 12)) +#define ISINK_CH_STEP_MASK GENMASK(14, 12) +#define ISINK_SFSTR0_TC(i) (((i) << 1) & GENMASK(2, 1)) +#define ISINK_SFSTR0_TC_MASK GENMASK(2, 1) +#define ISINK_SFSTR0_EN BIT(0) +#define ISINK_SFSTR0_EN_MASK BIT(0) + +/* Register to LED channel enablement */ +#define MTK_MT6323_ISINK_EN_CTRL 0x0356 +#define ISINK_CH_EN(i) BIT(i) +#define ISINK_CH_EN_MASK(i) BIT(i) + +#define MTK_MAX_PERIOD 10000 +#define MTK_MAX_DEVICES 4 +#define MTK_MAX_BRIGHTNESS 6 + +struct mtk_led; +struct mtk_leds; + +/** + * struct mtk_led - state container for the LED device + * @id: the identifier in MT6323 LED device + * @parent: the pointer to MT6323 LED controller + * @cdev: LED class device for this LED device + * @current_brightness: current state of the LED device + */ +struct mtk_led { + int id; + struct mtk_leds *parent; + struct led_classdev cdev; + u8 current_brightness; +}; + +/* struct mtk_leds - state container for holding LED controller + * of the driver + * @dev: The device pointer + * @hw: The underlying hardware providing shared + bus for the register operations + * @led_num: How much the LED device the controller could control + * @lock: The lock among process context + * @led: The array that contains the state of individual + LED device + */ +struct mtk_leds { + struct device *dev; + struct mt6397_chip *hw; + u8 led_num; + /* protect among process context */ + struct mutex lock; + struct mtk_led led[4]; +}; + +static void mtk_led_hw_off(struct led_classdev *cdev) +{ + struct mtk_led *led = container_of(cdev, struct mtk_led, cdev); + struct mtk_leds *leds = led->parent; + struct regmap *regmap = leds->hw->regmap; + unsigned int status; + + status = ISINK_CH_EN(led->id); + regmap_update_bits(regmap, MTK_MT6323_ISINK_EN_CTRL, + ISINK_CH_EN_MASK(led->id), ~status); + + usleep_range(100, 300); + regmap_update_bits(regmap, MTK_MT6323_TOP_CKPDN2, + RG_ISINK_CK_PDN_MASK(led->id), + RG_ISINK_CK_PDN(led->id)); + + dev_dbg(leds->dev, "%s called for led%d\n", + __func__, led->id); +} + +static u8 get_mtk_led_hw_brightness(struct led_classdev *cdev) +{ + struct mtk_led *led = container_of(cdev, struct mtk_led, cdev); + struct mtk_leds *leds = led->parent; + struct regmap *regmap = leds->hw->regmap; + unsigned int status; + + regmap_read(regmap, MTK_MT6323_TOP_CKPDN2, &status); + if (status & RG_ISINK_CK_PDN_MASK(led->id)) + return 0; + + regmap_read(regmap, MTK_MT6323_ISINK_EN_CTRL, &status); + if (!(status & ISINK_CH_EN(led->id))) + return 0; + + regmap_read(regmap, MTK_MT6323_ISINK_CON2(led->id), &status); + return ((status & ISINK_CH_STEP_MASK) >> 12) + 1; +} + +static void mtk_led_hw_on(struct led_classdev *cdev) +{ + struct mtk_led *led = container_of(cdev, struct mtk_led, cdev); + struct mtk_leds *leds = led->parent; + struct regmap *regmap = leds->hw->regmap; + unsigned int status; + + /* Setup required clock source, enable the corresponding + * clock and channel and let work with continuous blink as + * the default + */ + regmap_update_bits(regmap, MTK_MT6323_TOP_CKCON1, + RG_ISINK_CK_SEL_MASK(led->id), 0); + + status = RG_ISINK_CK_PDN(led->id); + regmap_update_bits(regmap, MTK_MT6323_TOP_CKPDN2, + RG_ISINK_CK_PDN_MASK(led->id), ~status); + + usleep_range(100, 300); + + regmap_update_bits(regmap, MTK_MT6323_ISINK_EN_CTRL, + ISINK_CH_EN_MASK(led->id), + ISINK_CH_EN(led->id)); + + regmap_update_bits(regmap, MTK_MT6323_ISINK_CON2(led->id), + ISINK_CH_STEP_MASK, + ISINK_CH_STEP(1)); + + regmap_update_bits(regmap, MTK_MT6323_ISINK_CON0(led->id), + ISINK_DIM_DUTY_MASK, ISINK_DIM_DUTY(31)); + + regmap_update_bits(regmap, MTK_MT6323_ISINK_CON1(led->id), + ISINK_DIM_FSEL_MASK, ISINK_DIM_FSEL(1000)); + + led->current_brightness = 1; + + dev_dbg(leds->dev, "%s called for led%d\n", + __func__, led->id); +} + +static int mtk_led_set_blink(struct led_classdev *cdev, + unsigned long *delay_on, + unsigned long *delay_off) +{ + struct mtk_led *led = container_of(cdev, struct mtk_led, cdev); + struct mtk_leds *leds = led->parent; + struct regmap *regmap = leds->hw->regmap; + u16 period; + u8 duty_cycle, duty_hw; + + /* Units are in ms , if over the hardware able + * to support, fallback into software blink + */ + if (*delay_on + *delay_off > MTK_MAX_PERIOD) + return -EINVAL; + + /* LED subsystem requires a default user + * friendly blink pattern for the LED so using + * 1Hz duty cycle 50% here if without specific + * value delay_on and delay off being assigned + */ + if (*delay_on == 0 && *delay_off == 0) { + *delay_on = 500; + *delay_off = 500; + } + + period = *delay_on + *delay_off; + + /* duty_cycle is the percentage of period during + * which the led is ON + */ + duty_cycle = 100 * (*delay_on) / period; + + mutex_lock(&leds->lock); + + if (!led->current_brightness) + mtk_led_hw_on(cdev); + + duty_hw = DIV_ROUND_CLOSEST(duty_cycle * 1000, 3125); + regmap_update_bits(regmap, MTK_MT6323_ISINK_CON0(led->id), + ISINK_DIM_DUTY_MASK, ISINK_DIM_DUTY(duty_hw)); + + regmap_update_bits(regmap, MTK_MT6323_ISINK_CON1(led->id), + ISINK_DIM_FSEL_MASK, ISINK_DIM_FSEL(period - 1)); + + mutex_unlock(&leds->lock); + + dev_dbg(leds->dev, "%s: Hardware blink! period=%dms duty=%d for led%d\n", + __func__, period, duty_cycle, led->id); + + return 0; +} + +static int mtk_led_set_brightness(struct led_classdev *cdev, + enum led_brightness brightness) +{ + struct mtk_led *led = container_of(cdev, struct mtk_led, cdev); + struct mtk_leds *leds = led->parent; + struct regmap *regmap = leds->hw->regmap; + + mutex_lock(&leds->lock); + + if (!led->current_brightness && brightness) + mtk_led_hw_on(cdev); + + if (brightness) { + /* Setup current output for the corresponding + * brightness level + */ + regmap_update_bits(regmap, MTK_MT6323_ISINK_CON2(led->id), + ISINK_CH_STEP_MASK, + ISINK_CH_STEP(brightness - 1)); + + regmap_update_bits(regmap, MTK_MT6323_ISINK_CON2(led->id), + ISINK_SFSTR0_TC_MASK | ISINK_SFSTR0_EN_MASK, + ISINK_SFSTR0_TC(2) | ISINK_SFSTR0_EN); + + dev_dbg(leds->dev, "Update led brightness:%d\n", + brightness); + } + + if (!brightness) + mtk_led_hw_off(cdev); + led->current_brightness = brightness; + + mutex_unlock(&leds->lock); + + return 0; +} + +static int mt6323_led_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = pdev->dev.of_node; + struct device_node *child; + struct mt6397_chip *hw = dev_get_drvdata(pdev->dev.parent); + struct mtk_leds *leds; + int ret, i = 0, count; + const char *state; + unsigned int status; + + count = of_get_child_count(np); + if (!count) + return -ENODEV; + + /* The number the LEDs on MT6323 could be support is + * up to MTK_MAX_DEVICES + */ + count = (count <= MTK_MAX_DEVICES) ? count : MTK_MAX_DEVICES; + + leds = devm_kzalloc(dev, sizeof(struct mtk_leds) + + sizeof(struct mtk_led) * count, + GFP_KERNEL); + if (!leds) + return -ENOMEM; + + platform_set_drvdata(pdev, leds); + leds->dev = dev; + + /* leds->hw points to the underlying bus for the register + * controlled + */ + leds->hw = hw; + mutex_init(&leds->lock); + leds->led_num = count; + + status = RG_DRV_32K_CK_PDN; + regmap_update_bits(leds->hw->regmap, MTK_MT6323_TOP_CKPDN0, + RG_DRV_32K_CK_PDN_MASK, ~status); + + /* Waiting for 32K stable prior to give the default value + * to each LED state decided through these useful common + * propertys such as label, linux,default-trigger and + * default-state + */ + usleep_range(300, 500); + + for_each_available_child_of_node(np, child) { + leds->led[i].cdev.name = + of_get_property(child, "label", NULL) ? : + child->name; + leds->led[i].cdev.default_trigger = of_get_property(child, + "linux,default-trigger", + NULL); + leds->led[i].cdev.max_brightness = MTK_MAX_BRIGHTNESS; + leds->led[i].cdev.brightness_set_blocking = + mtk_led_set_brightness; + leds->led[i].cdev.blink_set = mtk_led_set_blink; + leds->led[i].id = i; + leds->led[i].parent = leds; + state = of_get_property(child, "default-state", NULL); + if (state) { + if (!strcmp(state, "keep")) { + leds->led[i].current_brightness = + get_mtk_led_hw_brightness(&leds->led[i].cdev); + } else if (!strcmp(state, "on")) { + mtk_led_set_brightness(&leds->led[i].cdev, 1); + } else { + mtk_led_set_brightness(&leds->led[i].cdev, + 0); + } + } + ret = devm_led_classdev_register(dev, &leds->led[i].cdev); + if (ret) { + dev_err(&pdev->dev, "Failed to register LED: %d\n", + ret); + return ret; + } + leds->led[i].cdev.dev->of_node = child; + i++; + } + + return 0; +} + +static int mt6323_led_remove(struct platform_device *pdev) +{ + struct mtk_leds *leds = platform_get_drvdata(pdev); + int i; + + /* Turned the LED to OFF state if driver removal */ + for (i = 0 ; i < leds->led_num ; i++) + mtk_led_hw_off(&leds->led[i].cdev); + + regmap_update_bits(leds->hw->regmap, MTK_MT6323_TOP_CKPDN0, + RG_DRV_32K_CK_PDN_MASK, RG_DRV_32K_CK_PDN); + return 0; +} + +static const struct of_device_id mt6323_led_dt_match[] = { + { .compatible = "mediatek,mt6323-led" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mt6323_led_dt_match); + +static struct platform_driver mt6323_led_driver = { + .probe = mt6323_led_probe, + .remove = mt6323_led_remove, + .driver = { + .name = "mt6323-led", + .of_match_table = mt6323_led_dt_match, + }, +}; + +module_platform_driver(mt6323_led_driver); + +MODULE_DESCRIPTION("LED driver for Mediatek MT6323 PMIC"); +MODULE_AUTHOR("Sean Wang <sean.wang@xxxxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html