backlight: Add support Skyworks SKY81452 backlight driver (f705806c) · Commits · e / devices / android_kernel_fairphone_FP4

drivers/video/backlight/Kconfig

+10 −0

Original line number	Diff line number	Diff line
		@@ -408,6 +408,16 @@ config BACKLIGHT_PANDORA
		If you have a Pandora console, say Y to enable the
		backlight driver.

		config BACKLIGHT_SKY81452
		tristate "Backlight driver for SKY81452"
		depends on BACKLIGHT_CLASS_DEVICE && MFD_SKY81452
		help
		If you have a Skyworks SKY81452, say Y to enable the
		backlight driver.

		To compile this driver as a module, choose M here: the module will
		be called sky81452-backlight

		config BACKLIGHT_TPS65217
		tristate "TPS65217 Backlight"
		depends on BACKLIGHT_CLASS_DEVICE && MFD_TPS65217

drivers/video/backlight/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -50,6 +50,7 @@ obj-$(CONFIG_BACKLIGHT_PANDORA) += pandora_bl.o
		obj-$(CONFIG_BACKLIGHT_PCF50633) += pcf50633-backlight.o
		obj-$(CONFIG_BACKLIGHT_PWM) += pwm_bl.o
		obj-$(CONFIG_BACKLIGHT_SAHARA) += kb3886_bl.o
		obj-$(CONFIG_BACKLIGHT_SKY81452) += sky81452-backlight.o
		obj-$(CONFIG_BACKLIGHT_TOSA) += tosa_bl.o
		obj-$(CONFIG_BACKLIGHT_TPS65217) += tps65217_bl.o
		obj-$(CONFIG_BACKLIGHT_WM831X) += wm831x_bl.o

drivers/video/backlight/sky81452-backlight.c

0 → 100644

+353 −0

Original line number	Diff line number	Diff line
		/*
		* sky81452-backlight.c SKY81452 backlight driver
		*
		* Copyright 2014 Skyworks Solutions Inc.
		* Author : Gyungoh Yoo <jack.yoo@skyworksinc.com>
		*
		* This program is free software; you can redistribute it and/or modify it
		* under the terms of the GNU General Public License version 2
		* 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.
		*
		* You should have received a copy of the GNU General Public License along
		* with this program; if not, see <http://www.gnu.org/licenses/>.
		*/

		#include <linux/backlight.h>
		#include <linux/err.h>
		#include <linux/gpio.h>
		#include <linux/init.h>
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/of.h>
		#include <linux/of_gpio.h>
		#include <linux/platform_device.h>
		#include <linux/regmap.h>
		#include <linux/platform_data/sky81452-backlight.h>
		#include <linux/slab.h>

		/* registers */
		#define SKY81452_REG0 0x00
		#define SKY81452_REG1 0x01
		#define SKY81452_REG2 0x02
		#define SKY81452_REG4 0x04
		#define SKY81452_REG5 0x05

		/* bit mask */
		#define SKY81452_CS 0xFF
		#define SKY81452_EN 0x3F
		#define SKY81452_IGPW 0x20
		#define SKY81452_PWMMD 0x10
		#define SKY81452_PHASE 0x08
		#define SKY81452_ILIM 0x04
		#define SKY81452_VSHRT 0x03
		#define SKY81452_OCP 0x80
		#define SKY81452_OTMP 0x40
		#define SKY81452_SHRT 0x3F
		#define SKY81452_OPN 0x3F

		#define SKY81452_DEFAULT_NAME "lcd-backlight"
		#define SKY81452_MAX_BRIGHTNESS (SKY81452_CS + 1)

		#define CTZ(b) __builtin_ctz(b)

		static int sky81452_bl_update_status(struct backlight_device *bd)
		{
		const struct sky81452_bl_platform_data *pdata =
		dev_get_platdata(bd->dev.parent);
		const unsigned int brightness = (unsigned int)bd->props.brightness;
		struct regmap *regmap = bl_get_data(bd);
		int ret;

		if (brightness > 0) {
		ret = regmap_write(regmap, SKY81452_REG0, brightness - 1);
		if (IS_ERR_VALUE(ret))
		return ret;

		return regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN,
		pdata->enable << CTZ(SKY81452_EN));
		}

		return regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN, 0);
		}

		static const struct backlight_ops sky81452_bl_ops = {
		.update_status = sky81452_bl_update_status,
		};

		static ssize_t sky81452_bl_store_enable(struct device *dev,
		struct device_attribute attr, const char buf, size_t count)
		{
		struct regmap *regmap = bl_get_data(to_backlight_device(dev));
		unsigned long value;
		int ret;

		ret = kstrtoul(buf, 16, &value);
		if (IS_ERR_VALUE(ret))
		return ret;

		ret = regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN,
		value << CTZ(SKY81452_EN));
		if (IS_ERR_VALUE(ret))
		return ret;

		return count;
		}

		static ssize_t sky81452_bl_show_open_short(struct device *dev,
		struct device_attribute attr, char buf)
		{
		struct regmap *regmap = bl_get_data(to_backlight_device(dev));
		unsigned int reg, value = 0;
		char tmp[3];
		int i, ret;

		reg = !strcmp(attr->attr.name, "open") ? SKY81452_REG5 : SKY81452_REG4;
		ret = regmap_read(regmap, reg, &value);
		if (IS_ERR_VALUE(ret))
		return ret;

		if (value & SKY81452_SHRT) {
		*buf = 0;
		for (i = 0; i < 6; i++) {
		if (value & 0x01) {
		sprintf(tmp, "%d ", i + 1);
		strcat(buf, tmp);
		}
		value >>= 1;
		}
		strcat(buf, "\n");
		} else {
		strcpy(buf, "none\n");
		}

		return strlen(buf);
		}

		static ssize_t sky81452_bl_show_fault(struct device *dev,
		struct device_attribute attr, char buf)
		{
		struct regmap *regmap = bl_get_data(to_backlight_device(dev));
		unsigned int value = 0;
		int ret;

		ret = regmap_read(regmap, SKY81452_REG4, &value);
		if (IS_ERR_VALUE(ret))
		return ret;

		*buf = 0;

		if (value & SKY81452_OCP)
		strcat(buf, "over-current ");

		if (value & SKY81452_OTMP)
		strcat(buf, "over-temperature");

		strcat(buf, "\n");
		return strlen(buf);
		}

		static DEVICE_ATTR(enable, S_IWGRP \| S_IWUSR, NULL, sky81452_bl_store_enable);
		static DEVICE_ATTR(open, S_IRUGO, sky81452_bl_show_open_short, NULL);
		static DEVICE_ATTR(short, S_IRUGO, sky81452_bl_show_open_short, NULL);
		static DEVICE_ATTR(fault, S_IRUGO, sky81452_bl_show_fault, NULL);

		static struct attribute *sky81452_bl_attribute[] = {
		&dev_attr_enable.attr,
		&dev_attr_open.attr,
		&dev_attr_short.attr,
		&dev_attr_fault.attr,
		NULL
		};

		static const struct attribute_group sky81452_bl_attr_group = {
		.attrs = sky81452_bl_attribute,
		};

		#ifdef CONFIG_OF
		static struct sky81452_bl_platform_data *sky81452_bl_parse_dt(
		struct device *dev)
		{
		struct device_node *np = of_node_get(dev->of_node);
		struct sky81452_bl_platform_data *pdata;
		int num_entry;
		unsigned int sources[6];
		int ret;

		if (!np) {
		dev_err(dev, "backlight node not found.\n");
		return ERR_PTR(-ENODATA);
		}

		pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
		if (!pdata) {
		of_node_put(np);
		return ERR_PTR(-ENOMEM);
		}

		of_property_read_string(np, "name", &pdata->name);
		pdata->ignore_pwm = of_property_read_bool(np, "skyworks,ignore-pwm");
		pdata->dpwm_mode = of_property_read_bool(np, "skyworks,dpwm-mode");
		pdata->phase_shift = of_property_read_bool(np, "skyworks,phase-shift");
		pdata->gpio_enable = of_get_gpio(np, 0);

		ret = of_property_count_u32_elems(np, "led-sources");
		if (IS_ERR_VALUE(ret)) {
		pdata->enable = SKY81452_EN >> CTZ(SKY81452_EN);
		} else {
		num_entry = ret;
		if (num_entry > 6)
		num_entry = 6;

		ret = of_property_read_u32_array(np, "led-sources", sources,
		num_entry);
		if (IS_ERR_VALUE(ret)) {
		dev_err(dev, "led-sources node is invalid.\n");
		return ERR_PTR(-EINVAL);
		}

		pdata->enable = 0;
		while (--num_entry)
		pdata->enable \|= (1 << sources[num_entry]);
		}

		ret = of_property_read_u32(np,
		"skyworks,short-detection-threshold-volt",
		&pdata->short_detection_threshold);
		if (IS_ERR_VALUE(ret))
		pdata->short_detection_threshold = 7;

		ret = of_property_read_u32(np, "skyworks,current-limit-mA",
		&pdata->boost_current_limit);
		if (IS_ERR_VALUE(ret))
		pdata->boost_current_limit = 2750;

		of_node_put(np);
		return pdata;
		}
		#else
		static struct sky81452_bl_platform_data *sky81452_bl_parse_dt(
		struct device *dev)
		{
		return ERR_PTR(-EINVAL);
		}
		#endif

		static int sky81452_bl_init_device(struct regmap *regmap,
		struct sky81452_bl_platform_data *pdata)
		{
		unsigned int value;

		value = pdata->ignore_pwm ? SKY81452_IGPW : 0;
		value \|= pdata->dpwm_mode ? SKY81452_PWMMD : 0;
		value \|= pdata->phase_shift ? 0 : SKY81452_PHASE;

		if (pdata->boost_current_limit == 2300)
		value \|= SKY81452_ILIM;
		else if (pdata->boost_current_limit != 2750)
		return -EINVAL;

		if (pdata->short_detection_threshold < 4 \|\|
		pdata->short_detection_threshold > 7)
		return -EINVAL;
		value \|= (7 - pdata->short_detection_threshold) << CTZ(SKY81452_VSHRT);

		return regmap_write(regmap, SKY81452_REG2, value);
		}

		static int sky81452_bl_probe(struct platform_device *pdev)
		{
		struct device *dev = &pdev->dev;
		struct regmap *regmap = dev_get_drvdata(dev->parent);
		struct sky81452_bl_platform_data *pdata = dev_get_platdata(dev);
		struct backlight_device *bd;
		struct backlight_properties props;
		const char *name;
		int ret;

		if (!pdata) {
		pdata = sky81452_bl_parse_dt(dev);
		if (IS_ERR(pdata))
		return PTR_ERR(pdata);
		}

		if (gpio_is_valid(pdata->gpio_enable)) {
		ret = devm_gpio_request_one(dev, pdata->gpio_enable,
		GPIOF_OUT_INIT_HIGH, "sky81452-en");
		if (IS_ERR_VALUE(ret)) {
		dev_err(dev, "failed to request GPIO. err=%d\n", ret);
		return ret;
		}
		}

		ret = sky81452_bl_init_device(regmap, pdata);
		if (IS_ERR_VALUE(ret)) {
		dev_err(dev, "failed to initialize. err=%d\n", ret);
		return ret;
		}

		memset(&props, 0, sizeof(props));
		props.max_brightness = SKY81452_MAX_BRIGHTNESS,
		name = pdata->name ? pdata->name : SKY81452_DEFAULT_NAME;
		bd = devm_backlight_device_register(dev, name, dev, regmap,
		&sky81452_bl_ops, &props);
		if (IS_ERR(bd)) {
		dev_err(dev, "failed to register. err=%ld\n", PTR_ERR(bd));
		return PTR_ERR(bd);
		}

		platform_set_drvdata(pdev, bd);

		ret = sysfs_create_group(&bd->dev.kobj, &sky81452_bl_attr_group);
		if (IS_ERR_VALUE(ret)) {
		dev_err(dev, "failed to create attribute. err=%d\n", ret);
		return ret;
		}

		return ret;
		}

		static int sky81452_bl_remove(struct platform_device *pdev)
		{
		const struct sky81452_bl_platform_data *pdata =
		dev_get_platdata(&pdev->dev);
		struct backlight_device *bd = platform_get_drvdata(pdev);

		sysfs_remove_group(&bd->dev.kobj, &sky81452_bl_attr_group);

		bd->props.power = FB_BLANK_UNBLANK;
		bd->props.brightness = 0;
		backlight_update_status(bd);

		if (gpio_is_valid(pdata->gpio_enable))
		gpio_set_value_cansleep(pdata->gpio_enable, 0);

		return 0;
		}

		#ifdef CONFIG_OF
		static const struct of_device_id sky81452_bl_of_match[] = {
		{ .compatible = "skyworks,sky81452-backlight", },
		{ }
		};
		MODULE_DEVICE_TABLE(of, sky81452_bl_of_match);
		#endif

		static struct platform_driver sky81452_bl_driver = {
		.driver = {
		.name = "sky81452-backlight",
		.of_match_table = of_match_ptr(sky81452_bl_of_match),
		},
		.probe = sky81452_bl_probe,
		.remove = sky81452_bl_remove,
		};

		module_platform_driver(sky81452_bl_driver);

		MODULE_DESCRIPTION("Skyworks SKY81452 backlight driver");
		MODULE_AUTHOR("Gyungoh Yoo <jack.yoo@skyworksinc.com>");
		MODULE_LICENSE("GPL v2");

include/linux/platform_data/sky81452-backlight.h

0 → 100644

+46 −0

Original line number	Diff line number	Diff line
		/*
		* sky81452.h SKY81452 backlight driver
		*
		* Copyright 2014 Skyworks Solutions Inc.
		* Author : Gyungoh Yoo <jack.yoo@skyworksinc.com>
		*
		* This program is free software; you can redistribute it and/or modify it
		* under the terms of the GNU General Public License version 2
		* 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.
		*
		* You should have received a copy of the GNU General Public License along
		* with this program; if not, see <http://www.gnu.org/licenses/>.
		*/

		#ifndef _SKY81452_BACKLIGHT_H
		#define _SKY81452_BACKLIGHT_H

		/**
		* struct sky81452_platform_data
		* @name: backlight driver name.
		If it is not defined, default name is lcd-backlight.
		* @gpio_enable:GPIO number which control EN pin
		* @enable: Enable mask for current sink channel 1, 2, 3, 4, 5 and 6.
		* @ignore_pwm: true if DPWMI should be ignored.
		* @dpwm_mode: true is DPWM dimming mode, otherwise Analog dimming mode.
		* @phase_shift:true is phase shift mode.
		* @short_detecion_threshold: It should be one of 4, 5, 6 and 7V.
		* @boost_current_limit: It should be one of 2300, 2750mA.
		*/
		struct sky81452_bl_platform_data {
		const char *name;
		int gpio_enable;
		unsigned int enable;
		bool ignore_pwm;
		bool dpwm_mode;
		bool phase_shift;
		unsigned int short_detection_threshold;
		unsigned int boost_current_limit;
		};

		#endif