--- /dev/null
+/* drivers/video/backlight/rk29_backlight.c
+ *
+ * Copyright (C) 2009-2011 Rockchip Corporation.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/backlight.h>
+#include <linux/fb.h>
+#include <linux/clk.h>
+
+#include <linux/earlysuspend.h>
+#include <asm/io.h>
+#include <mach/rk29_iomap.h>
+#include <mach/board.h>
+
+#include "rk2818_backlight.h"
+
+/*
+ * Debug
+ */
+#if 0
+#define DBG(x...) printk(KERN_INFO x)
+#else
+#define DBG(x...)
+#endif
+
+
+#define write_pwm_reg(id, addr, val) __raw_writel(val, addr+(RK29_PWM_BASE+id*0x10))
+#define read_pwm_reg(id, addr) __raw_readl(addr+(RK29_PWM_BASE+id*0x10))
+
+static struct clk *pwm_clk;
+static struct backlight_device *rk29_bl;
+static int suspend_flag = 0;
+
+static int rk29_bl_update_status(struct backlight_device *bl)
+{
+ u32 divh,div_total;
+ struct rk29_bl_info *rk29_bl_info = bl_get_data(bl);
+ u32 id = rk29_bl_info->pwm_id;
+ u32 ref = rk29_bl_info->bl_ref;
+
+ if (suspend_flag)
+ return 0;
+
+ if (bl->props.brightness < rk29_bl_info->min_brightness) /*avoid can't view screen when close backlight*/
+ bl->props.brightness = rk29_bl_info->min_brightness;
+
+ div_total = read_pwm_reg(id, PWM_REG_LRC);
+ if (ref) {
+ divh = div_total*(bl->props.brightness)/BL_STEP;
+ } else {
+ divh = div_total*(BL_STEP-bl->props.brightness)/BL_STEP;
+ }
+ write_pwm_reg(id, PWM_REG_HRC, divh);
+
+ DBG(">>>%s-->%d brightness = %d, div_total = %d, divh = %d\n",__FUNCTION__,__LINE__,bl->props.brightness, div_total, divh);
+ return 0;
+}
+
+static int rk29_bl_get_brightness(struct backlight_device *bl)
+{
+ u32 divh,div_total;
+ struct rk29_bl_info *rk29_bl_info = bl_get_data(bl);
+ u32 id = rk29_bl_info->pwm_id;
+ u32 ref = rk29_bl_info->bl_ref;
+
+ div_total = read_pwm_reg(id, PWM_REG_LRC);
+ divh = read_pwm_reg(id, PWM_REG_HRC);
+
+ if (!div_total)
+ return 0;
+
+ if (ref) {
+ return BL_STEP*divh/div_total;
+ } else {
+ return BL_STEP-(BL_STEP*divh/div_total);
+ }
+}
+
+static struct backlight_ops rk29_bl_ops = {
+ .update_status = rk29_bl_update_status,
+ .get_brightness = rk29_bl_get_brightness,
+};
+
+static void rk29_backlight_work_func(struct work_struct *work)
+{
+ suspend_flag = 0;
+ rk29_bl_update_status(rk29_bl);
+}
+static DECLARE_DELAYED_WORK(rk29_backlight_work, rk29_backlight_work_func);
+
+#ifdef CONFIG_HAS_EARLYSUSPEND
+static void rk29_bl_suspend(struct early_suspend *h)
+{
+ struct rk29_bl_info *rk29_bl_info = bl_get_data(rk29_bl);
+ int brightness = rk29_bl->props.brightness;
+
+ cancel_delayed_work_sync(&rk29_backlight_work);
+
+ if (rk29_bl->props.brightness) {
+ rk29_bl->props.brightness = 0;
+ rk29_bl_update_status(rk29_bl);
+ rk29_bl->props.brightness = brightness;
+ }
+
+ if (!suspend_flag) {
+ clk_disable(pwm_clk);
+ if (rk29_bl_info->pwm_suspend)
+ rk29_bl_info->pwm_suspend();
+ }
+
+ suspend_flag = 1;
+}
+
+static void rk29_bl_resume(struct early_suspend *h)
+{
+ struct rk29_bl_info *rk29_bl_info = bl_get_data(rk29_bl);
+ DBG("%s : %s\n", __FILE__, __FUNCTION__);
+
+ if (rk29_bl_info->pwm_resume)
+ rk29_bl_info->pwm_resume();
+
+ clk_enable(pwm_clk);
+
+ schedule_delayed_work(&rk29_backlight_work, msecs_to_jiffies(rk29_bl_info->delay_ms));
+}
+
+static struct early_suspend bl_early_suspend = {
+ .suspend = rk29_bl_suspend,
+ .resume = rk29_bl_resume,
+ .level = EARLY_SUSPEND_LEVEL_BLANK_SCREEN - 1,
+};
+#endif
+
+static int rk29_backlight_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct rk29_bl_info *rk29_bl_info = pdev->dev.platform_data;
+ u32 id = rk29_bl_info->pwm_id;
+ u32 divh, div_total;
+ unsigned long pwm_clk_rate;
+
+ if (rk29_bl) {
+ DBG(KERN_CRIT "%s: backlight device register has existed \n",
+ __func__);
+ return -EEXIST;
+ }
+
+ if (!rk29_bl_info->delay_ms)
+ rk29_bl_info->delay_ms = 100;
+
+ if (rk29_bl_info->min_brightness < 0 || rk29_bl_info->min_brightness > BL_STEP)
+ rk29_bl_info->min_brightness = 52;
+
+ if (rk29_bl_info && rk29_bl_info->io_init) {
+ rk29_bl_info->io_init();
+ }
+
+ rk29_bl = backlight_device_register("rk28_bl", &pdev->dev, rk29_bl_info, &rk29_bl_ops);
+ if (!rk29_bl) {
+ DBG(KERN_CRIT "%s: backlight device register error\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ pwm_clk = clk_get(NULL, "pwm");
+ if (IS_ERR(pwm_clk)) {
+ printk(KERN_ERR "failed to get pwm clock source\n");
+ return -ENODEV;
+ }
+ pwm_clk_rate = clk_get_rate(pwm_clk);
+ div_total = pwm_clk_rate / PWM_APB_PRE_DIV;
+
+ div_total >>= (1 + (PWM_DIV >> 9));
+ div_total = (div_total) ? div_total : 1;
+
+ if(rk29_bl_info->bl_ref) {
+ divh = 0;
+ } else {
+ divh = div_total;
+ }
+
+ clk_enable(pwm_clk);
+ write_pwm_reg(id, PWM_REG_CTRL, PWM_DIV|PWM_RESET);
+ write_pwm_reg(id, PWM_REG_LRC, div_total);
+ write_pwm_reg(id, PWM_REG_HRC, divh);
+ write_pwm_reg(id, PWM_REG_CNTR, 0x0);
+ write_pwm_reg(id, PWM_REG_CTRL, PWM_DIV|PWM_ENABLE|PWM_TIME_EN);
+
+ rk29_bl->props.power = FB_BLANK_UNBLANK;
+ rk29_bl->props.fb_blank = FB_BLANK_UNBLANK;
+ rk29_bl->props.max_brightness = BL_STEP;
+ rk29_bl->props.brightness = BL_STEP / 2;
+
+ if (rk29_bl_info && rk29_bl_info->pwm_resume) {
+ rk29_bl_info->pwm_resume();
+ }
+
+ schedule_delayed_work(&rk29_backlight_work, msecs_to_jiffies(rk29_bl_info->delay_ms));
+
+ register_early_suspend(&bl_early_suspend);
+
+ printk("RK29 Backlight Driver Initialized.\n");
+ return ret;
+}
+
+static int rk29_backlight_remove(struct platform_device *pdev)
+{
+ struct rk29_bl_info *rk29_bl_info = pdev->dev.platform_data;
+
+ if (rk29_bl) {
+ backlight_device_unregister(rk29_bl);
+ unregister_early_suspend(&bl_early_suspend);
+ clk_disable(pwm_clk);
+ clk_put(pwm_clk);
+ if (rk29_bl_info && rk29_bl_info->io_deinit) {
+ rk29_bl_info->io_deinit();
+ }
+ return 0;
+ } else {
+ DBG(KERN_CRIT "%s: no backlight device has registered\n",
+ __func__);
+ return -ENODEV;
+ }
+}
+
+static void rk29_backlight_shutdown(struct platform_device *pdev)
+{
+ struct rk29_bl_info *rk29_bl_info = pdev->dev.platform_data;
+
+ rk29_bl->props.brightness >>= 1;
+ rk29_bl_update_status(rk29_bl);
+ mdelay(100);
+
+ rk29_bl->props.brightness >>= 1;
+ rk29_bl_update_status(rk29_bl);
+ mdelay(100);
+
+ rk29_bl->props.brightness = 0;
+ rk29_bl_update_status(rk29_bl);
+
+ if (rk29_bl_info && rk29_bl_info->io_deinit)
+ rk29_bl_info->io_deinit();
+}
+
+static struct platform_driver rk29_backlight_driver = {
+ .probe = rk29_backlight_probe,
+ .remove = rk29_backlight_remove,
+ .driver = {
+ .name = "rk29_backlight",
+ .owner = THIS_MODULE,
+ },
+ .shutdown = rk29_backlight_shutdown,
+};
+
+static int __init rk29_backlight_init(void)
+{
+ platform_driver_register(&rk29_backlight_driver);
+ return 0;
+}
+fs_initcall_sync(rk29_backlight_init);
projects / firefly-linux-kernel-4.4.55.git / commitdiff