From: Gyungoh Yoo <jack.yoo@xxxxxxxxxxxxxxx> Signed-off-by: Gyungoh Yoo <jack.yoo@xxxxxxxxxxxxxxx> --- Changes v7: Modified licensing text to GPLv2 Changes v6: Added new line character at the end of line of dev_err() Changes v5: Move sky81452-backlight.h to include/linux/platform_data Changes v4: Reordering header files for readability Removed calling to backlight_device_unregister() Removed MODULE_VERSION() Modified license to GPLv2 Changes v3: Modified DBG messages Changes v2: Added 'compatible' attribute in the driver Added message for exception or errors drivers/video/backlight/Kconfig | 10 + drivers/video/backlight/Makefile | 1 + drivers/video/backlight/sky81452-backlight.c | 343 +++++++++++++++++++++++ include/linux/platform_data/sky81452-backlight.h | 46 +++ 4 files changed, 400 insertions(+) create mode 100644 drivers/video/backlight/sky81452-backlight.c create mode 100644 include/linux/platform_data/sky81452-backlight.h diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 8d03924..2586fdd 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -409,6 +409,16 @@ 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 diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index fcd50b73..d67073f 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -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 diff --git a/drivers/video/backlight/sky81452-backlight.c b/drivers/video/backlight/sky81452-backlight.c new file mode 100644 index 0000000..9c1139e --- /dev/null +++ b/drivers/video/backlight/sky81452-backlight.c @@ -0,0 +1,343 @@ +/* + * sky81452-backlight.c SKY81452 backlight driver + * + * Copyright 2014 Skyworks Solutions Inc. + * Author : Gyungoh Yoo <jack.yoo@xxxxxxxxxxxxxxx> + * + * 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 int sky81452_bl_get_brightness(struct backlight_device *bd) +{ + return bd->props.brightness; +} + +static const struct backlight_ops sky81452_bl_ops = { + .update_status = sky81452_bl_update_status, + .get_brightness = sky81452_bl_get_brightness, +}; + +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 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, "ignore-pwm"); + pdata->dpwm_mode = of_property_read_bool(np, "dpwm-mode"); + pdata->phase_shift = of_property_read_bool(np, "phase-shift"); + + pdata->gpio_enable = of_get_named_gpio(np, "gpio-enable", 0); + if (IS_ERR_VALUE(pdata->gpio_enable)) + pdata->gpio_enable = -1; + + ret = of_property_read_u32(np, "enable", &pdata->enable); + if (IS_ERR_VALUE(ret)) + pdata->enable = SKY81452_EN >> CTZ(SKY81452_EN); + + ret = of_property_read_u32(np, "short-detection-threshold", + &pdata->short_detection_threshold); + if (IS_ERR_VALUE(ret)) + pdata->short_detection_threshold = 7; + + ret = of_property_read_u32(np, "boost-current-limit", + &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 != 2720) + 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 (pdata->gpio_enable >= 0) { + 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 (pdata->gpio_enable >= 0) + 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@xxxxxxxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/platform_data/sky81452-backlight.h b/include/linux/platform_data/sky81452-backlight.h new file mode 100644 index 0000000..1231e9b --- /dev/null +++ b/include/linux/platform_data/sky81452-backlight.h @@ -0,0 +1,46 @@ +/* + * sky81452.h SKY81452 backlight driver + * + * Copyright 2014 Skyworks Solutions Inc. + * Author : Gyungoh Yoo <jack.yoo@xxxxxxxxxxxxxxx> + * + * 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 -- 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
