| /* |
| * lm3533-bl.c -- LM3533 Backlight driver |
| * |
| * Copyright (C) 2011-2012 Texas Instruments |
| * |
| * Author: Johan Hovold <jhovold@gmail.com> |
| * |
| * 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. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/platform_device.h> |
| #include <linux/backlight.h> |
| #include <linux/fb.h> |
| #include <linux/slab.h> |
| |
| #include <linux/mfd/lm3533.h> |
| |
| |
| #define LM3533_HVCTRLBANK_COUNT 2 |
| #define LM3533_BL_MAX_BRIGHTNESS 255 |
| |
| #define LM3533_REG_CTRLBANK_AB_BCONF 0x1a |
| |
| |
| struct lm3533_bl { |
| struct lm3533 *lm3533; |
| struct lm3533_ctrlbank cb; |
| struct backlight_device *bd; |
| int id; |
| }; |
| |
| |
| static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl) |
| { |
| return bl->id; |
| } |
| |
| static int lm3533_bl_update_status(struct backlight_device *bd) |
| { |
| struct lm3533_bl *bl = bl_get_data(bd); |
| int brightness = bd->props.brightness; |
| |
| if (bd->props.power != FB_BLANK_UNBLANK) |
| brightness = 0; |
| if (bd->props.fb_blank != FB_BLANK_UNBLANK) |
| brightness = 0; |
| |
| return lm3533_ctrlbank_set_brightness(&bl->cb, (u8)brightness); |
| } |
| |
| static int lm3533_bl_get_brightness(struct backlight_device *bd) |
| { |
| struct lm3533_bl *bl = bl_get_data(bd); |
| u8 val; |
| int ret; |
| |
| ret = lm3533_ctrlbank_get_brightness(&bl->cb, &val); |
| if (ret) |
| return ret; |
| |
| return val; |
| } |
| |
| static const struct backlight_ops lm3533_bl_ops = { |
| .get_brightness = lm3533_bl_get_brightness, |
| .update_status = lm3533_bl_update_status, |
| }; |
| |
| static ssize_t show_id(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| |
| return scnprintf(buf, PAGE_SIZE, "%d\n", bl->id); |
| } |
| |
| static ssize_t show_als_channel(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| unsigned channel = lm3533_bl_get_ctrlbank_id(bl); |
| |
| return scnprintf(buf, PAGE_SIZE, "%u\n", channel); |
| } |
| |
| static ssize_t show_als_en(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| int ctrlbank = lm3533_bl_get_ctrlbank_id(bl); |
| u8 val; |
| u8 mask; |
| bool enable; |
| int ret; |
| |
| ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val); |
| if (ret) |
| return ret; |
| |
| mask = 1 << (2 * ctrlbank); |
| enable = val & mask; |
| |
| return scnprintf(buf, PAGE_SIZE, "%d\n", enable); |
| } |
| |
| static ssize_t store_als_en(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t len) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| int ctrlbank = lm3533_bl_get_ctrlbank_id(bl); |
| int enable; |
| u8 val; |
| u8 mask; |
| int ret; |
| |
| if (kstrtoint(buf, 0, &enable)) |
| return -EINVAL; |
| |
| mask = 1 << (2 * ctrlbank); |
| |
| if (enable) |
| val = mask; |
| else |
| val = 0; |
| |
| ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val, |
| mask); |
| if (ret) |
| return ret; |
| |
| return len; |
| } |
| |
| static ssize_t show_linear(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| u8 val; |
| u8 mask; |
| int linear; |
| int ret; |
| |
| ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val); |
| if (ret) |
| return ret; |
| |
| mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1); |
| |
| if (val & mask) |
| linear = 1; |
| else |
| linear = 0; |
| |
| return scnprintf(buf, PAGE_SIZE, "%x\n", linear); |
| } |
| |
| static ssize_t store_linear(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t len) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| unsigned long linear; |
| u8 mask; |
| u8 val; |
| int ret; |
| |
| if (kstrtoul(buf, 0, &linear)) |
| return -EINVAL; |
| |
| mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1); |
| |
| if (linear) |
| val = mask; |
| else |
| val = 0; |
| |
| ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val, |
| mask); |
| if (ret) |
| return ret; |
| |
| return len; |
| } |
| |
| static ssize_t show_pwm(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| u8 val; |
| int ret; |
| |
| ret = lm3533_ctrlbank_get_pwm(&bl->cb, &val); |
| if (ret) |
| return ret; |
| |
| return scnprintf(buf, PAGE_SIZE, "%u\n", val); |
| } |
| |
| static ssize_t store_pwm(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t len) |
| { |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| u8 val; |
| int ret; |
| |
| if (kstrtou8(buf, 0, &val)) |
| return -EINVAL; |
| |
| ret = lm3533_ctrlbank_set_pwm(&bl->cb, val); |
| if (ret) |
| return ret; |
| |
| return len; |
| } |
| |
| static LM3533_ATTR_RO(als_channel); |
| static LM3533_ATTR_RW(als_en); |
| static LM3533_ATTR_RO(id); |
| static LM3533_ATTR_RW(linear); |
| static LM3533_ATTR_RW(pwm); |
| |
| static struct attribute *lm3533_bl_attributes[] = { |
| &dev_attr_als_channel.attr, |
| &dev_attr_als_en.attr, |
| &dev_attr_id.attr, |
| &dev_attr_linear.attr, |
| &dev_attr_pwm.attr, |
| NULL, |
| }; |
| |
| static umode_t lm3533_bl_attr_is_visible(struct kobject *kobj, |
| struct attribute *attr, int n) |
| { |
| struct device *dev = container_of(kobj, struct device, kobj); |
| struct lm3533_bl *bl = dev_get_drvdata(dev); |
| umode_t mode = attr->mode; |
| |
| if (attr == &dev_attr_als_channel.attr || |
| attr == &dev_attr_als_en.attr) { |
| if (!bl->lm3533->have_als) |
| mode = 0; |
| } |
| |
| return mode; |
| }; |
| |
| static struct attribute_group lm3533_bl_attribute_group = { |
| .is_visible = lm3533_bl_attr_is_visible, |
| .attrs = lm3533_bl_attributes |
| }; |
| |
| static int lm3533_bl_setup(struct lm3533_bl *bl, |
| struct lm3533_bl_platform_data *pdata) |
| { |
| int ret; |
| |
| ret = lm3533_ctrlbank_set_max_current(&bl->cb, pdata->max_current); |
| if (ret) |
| return ret; |
| |
| return lm3533_ctrlbank_set_pwm(&bl->cb, pdata->pwm); |
| } |
| |
| static int lm3533_bl_probe(struct platform_device *pdev) |
| { |
| struct lm3533 *lm3533; |
| struct lm3533_bl_platform_data *pdata; |
| struct lm3533_bl *bl; |
| struct backlight_device *bd; |
| struct backlight_properties props; |
| int ret; |
| |
| dev_dbg(&pdev->dev, "%s\n", __func__); |
| |
| lm3533 = dev_get_drvdata(pdev->dev.parent); |
| if (!lm3533) |
| return -EINVAL; |
| |
| pdata = pdev->dev.platform_data; |
| if (!pdata) { |
| dev_err(&pdev->dev, "no platform data\n"); |
| return -EINVAL; |
| } |
| |
| if (pdev->id < 0 || pdev->id >= LM3533_HVCTRLBANK_COUNT) { |
| dev_err(&pdev->dev, "illegal backlight id %d\n", pdev->id); |
| return -EINVAL; |
| } |
| |
| bl = devm_kzalloc(&pdev->dev, sizeof(*bl), GFP_KERNEL); |
| if (!bl) { |
| dev_err(&pdev->dev, |
| "failed to allocate memory for backlight\n"); |
| return -ENOMEM; |
| } |
| |
| bl->lm3533 = lm3533; |
| bl->id = pdev->id; |
| |
| bl->cb.lm3533 = lm3533; |
| bl->cb.id = lm3533_bl_get_ctrlbank_id(bl); |
| bl->cb.dev = NULL; /* until registered */ |
| |
| memset(&props, 0, sizeof(props)); |
| props.type = BACKLIGHT_RAW; |
| props.max_brightness = LM3533_BL_MAX_BRIGHTNESS; |
| props.brightness = pdata->default_brightness; |
| bd = backlight_device_register(pdata->name, pdev->dev.parent, bl, |
| &lm3533_bl_ops, &props); |
| if (IS_ERR(bd)) { |
| dev_err(&pdev->dev, "failed to register backlight device\n"); |
| return PTR_ERR(bd); |
| } |
| |
| bl->bd = bd; |
| bl->cb.dev = &bl->bd->dev; |
| |
| platform_set_drvdata(pdev, bl); |
| |
| ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "failed to create sysfs attributes\n"); |
| goto err_unregister; |
| } |
| |
| backlight_update_status(bd); |
| |
| ret = lm3533_bl_setup(bl, pdata); |
| if (ret) |
| goto err_sysfs_remove; |
| |
| ret = lm3533_ctrlbank_enable(&bl->cb); |
| if (ret) |
| goto err_sysfs_remove; |
| |
| return 0; |
| |
| err_sysfs_remove: |
| sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group); |
| err_unregister: |
| backlight_device_unregister(bd); |
| |
| return ret; |
| } |
| |
| static int lm3533_bl_remove(struct platform_device *pdev) |
| { |
| struct lm3533_bl *bl = platform_get_drvdata(pdev); |
| struct backlight_device *bd = bl->bd; |
| |
| dev_dbg(&bd->dev, "%s\n", __func__); |
| |
| bd->props.power = FB_BLANK_POWERDOWN; |
| bd->props.brightness = 0; |
| |
| lm3533_ctrlbank_disable(&bl->cb); |
| sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group); |
| backlight_device_unregister(bd); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| static int lm3533_bl_suspend(struct platform_device *pdev, pm_message_t state) |
| { |
| struct lm3533_bl *bl = platform_get_drvdata(pdev); |
| |
| dev_dbg(&pdev->dev, "%s\n", __func__); |
| |
| return lm3533_ctrlbank_disable(&bl->cb); |
| } |
| |
| static int lm3533_bl_resume(struct platform_device *pdev) |
| { |
| struct lm3533_bl *bl = platform_get_drvdata(pdev); |
| |
| dev_dbg(&pdev->dev, "%s\n", __func__); |
| |
| return lm3533_ctrlbank_enable(&bl->cb); |
| } |
| #else |
| #define lm3533_bl_suspend NULL |
| #define lm3533_bl_resume NULL |
| #endif |
| |
| static void lm3533_bl_shutdown(struct platform_device *pdev) |
| { |
| struct lm3533_bl *bl = platform_get_drvdata(pdev); |
| |
| dev_dbg(&pdev->dev, "%s\n", __func__); |
| |
| lm3533_ctrlbank_disable(&bl->cb); |
| } |
| |
| static struct platform_driver lm3533_bl_driver = { |
| .driver = { |
| .name = "lm3533-backlight", |
| .owner = THIS_MODULE, |
| }, |
| .probe = lm3533_bl_probe, |
| .remove = lm3533_bl_remove, |
| .shutdown = lm3533_bl_shutdown, |
| .suspend = lm3533_bl_suspend, |
| .resume = lm3533_bl_resume, |
| }; |
| module_platform_driver(lm3533_bl_driver); |
| |
| MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>"); |
| MODULE_DESCRIPTION("LM3533 Backlight driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:lm3533-backlight"); |