1 /* drivers/video/backlight/rk29_backlight.c
3 * Copyright (C) 2009-2011 Rockchip Corporation.
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/err.h>
20 #include <linux/delay.h>
21 #include <linux/platform_device.h>
22 #include <linux/backlight.h>
24 #include <linux/clk.h>
26 #include <linux/earlysuspend.h>
28 #include <mach/board.h>
30 #include "rk2818_backlight.h"
36 #define DBG(x...) printk(KERN_INFO x)
41 #if defined(CONFIG_ARCH_RK30)
42 #define write_pwm_reg(id, addr, val) __raw_writel(val, addr+(RK30_PWM01_BASE+(id>>1)*0x20000)+id*0x10)
43 #define read_pwm_reg(id, addr) __raw_readl(addr+(RK30_PWM01_BASE+(id>>1)*0x20000+id*0x10))
45 #elif defined(CONFIG_ARCH_RK2928)
46 #define write_pwm_reg(id, addr, val) __raw_writel(val, addr+(RK2928_PWM_BASE+id*0x10))
47 #define read_pwm_reg(id, addr) __raw_readl(addr+(RK2928_PWM_BASE+id*0x10))
49 #elif defined(CONFIG_ARCH_RK29)
50 #define write_pwm_reg(id, addr, val) __raw_writel(val, addr+(RK29_PWM_BASE+id*0x10))
51 #define read_pwm_reg(id, addr) __raw_readl(addr+(RK29_PWM_BASE+id*0x10))
54 static struct clk *pwm_clk;
55 static struct backlight_device *rk29_bl;
56 static int suspend_flag = 0;
59 int convertint(char s[])
63 for (i = 0; s[i] >= '0' && s[i] <= '9'; ++i)
65 n = 10 * n + (s[i] - '0');
70 static ssize_t backlight_write(struct device *dev,
71 struct device_attribute *attr, char *buf)
74 struct rk29_bl_info *rk29_bl_info = bl_get_data(rk29_bl);
77 number = convertint(buf);
79 rk29_bl_info->min_brightness=number;
84 static ssize_t backlight_read(struct device *dev,
85 struct device_attribute *attr, char *buf)
87 struct rk29_bl_info *rk29_bl_info = bl_get_data(rk29_bl);
89 DBG("rk29_bl_info->min_brightness=%d\n",rk29_bl_info->min_brightness);
91 static DEVICE_ATTR(rk29backlight, 0660, backlight_read, backlight_write);
93 static DEFINE_MUTEX(backlight_mutex);
95 static int rk29_bl_update_status(struct backlight_device *bl)
98 struct rk29_bl_info *rk29_bl_info = bl_get_data(bl);
99 u32 id = rk29_bl_info->pwm_id;
100 u32 ref = rk29_bl_info->bl_ref;
103 mutex_lock(&backlight_mutex);
104 //BL_CORE_DRIVER2 is the flag if backlight is into early_suspend.
105 if (suspend_flag && (bl->props.state & BL_CORE_DRIVER2))
108 brightness = bl->props.brightness;
109 if(rk29_bl_info->min_brightness){
111 brightness = brightness*(256 - rk29_bl_info->min_brightness);
112 brightness = (brightness>>8) + rk29_bl_info->min_brightness;
118 if (bl->props.power != FB_BLANK_UNBLANK)
121 if (bl->props.fb_blank != FB_BLANK_UNBLANK)
124 if ((bl->props.state & BL_CORE_DRIVER2) && !suspend_flag ){
127 }else if(!(bl->props.state & BL_CORE_DRIVER2) && suspend_flag ){
131 //BL_CORE_DRIVER1 is the flag if backlight pwm is closed.
132 if ((bl->props.state & BL_CORE_DRIVER1) && brightness ==0 ){
133 bl->props.state &= ~BL_CORE_DRIVER1;
134 clk_disable(pwm_clk);
135 if (rk29_bl_info->pwm_suspend)
136 rk29_bl_info->pwm_suspend();
137 }else if(!(bl->props.state & BL_CORE_DRIVER1) && brightness != 0){
138 bl->props.state |= BL_CORE_DRIVER1;
139 if (rk29_bl_info->pwm_resume)
140 rk29_bl_info->pwm_resume();
145 div_total = read_pwm_reg(id, PWM_REG_LRC);
147 divh = div_total*brightness/BL_STEP;
149 divh = div_total*(BL_STEP-brightness)/BL_STEP;
151 write_pwm_reg(id, PWM_REG_HRC, divh);
153 DBG("%s:line=%d,brightness = %d, div_total = %d, divh = %d state=%x \n",__FUNCTION__,__LINE__,brightness, div_total, divh,bl->props.state);
155 mutex_unlock(&backlight_mutex);
159 static int rk29_bl_get_brightness(struct backlight_device *bl)
162 struct rk29_bl_info *rk29_bl_info = bl_get_data(bl);
163 u32 id = rk29_bl_info->pwm_id;
164 u32 ref = rk29_bl_info->bl_ref;
166 div_total = read_pwm_reg(id, PWM_REG_LRC);
167 divh = read_pwm_reg(id, PWM_REG_HRC);
173 return BL_STEP*divh/div_total;
175 return BL_STEP-(BL_STEP*divh/div_total);
179 static struct backlight_ops rk29_bl_ops = {
180 .update_status = rk29_bl_update_status,
181 .get_brightness = rk29_bl_get_brightness,
184 static void rk29_backlight_work_func(struct work_struct *work)
186 rk29_bl->props.state &= ~BL_CORE_DRIVER2;
187 rk29_bl_update_status(rk29_bl);
189 static DECLARE_DELAYED_WORK(rk29_backlight_work, rk29_backlight_work_func);
191 #ifdef CONFIG_HAS_EARLYSUSPEND
192 static void rk29_bl_suspend(struct early_suspend *h)
194 struct rk29_bl_info *rk29_bl_info = bl_get_data(rk29_bl);
195 int brightness = rk29_bl->props.brightness;
197 cancel_delayed_work_sync(&rk29_backlight_work);
199 rk29_bl->props.state |= BL_CORE_DRIVER2;
201 if (rk29_bl->props.brightness) {
202 rk29_bl->props.brightness = 0;
203 rk29_bl_update_status(rk29_bl);
204 rk29_bl->props.brightness = brightness;
209 static void rk29_bl_resume(struct early_suspend *h)
211 struct rk29_bl_info *rk29_bl_info = bl_get_data(rk29_bl);
212 DBG("%s : %s\n", __FILE__, __FUNCTION__);
214 schedule_delayed_work(&rk29_backlight_work, msecs_to_jiffies(rk29_bl_info->delay_ms));
217 static struct early_suspend bl_early_suspend = {
218 .suspend = rk29_bl_suspend,
219 .resume = rk29_bl_resume,
220 .level = EARLY_SUSPEND_LEVEL_BLANK_SCREEN - 1,
223 bool rk29_get_backlight_status()
225 return (rk29_bl->props.state & BL_CORE_DRIVER1)?true:false;
227 EXPORT_SYMBOL(rk29_get_backlight_status);
229 void rk29_backlight_set(bool on)
231 printk("%s: set %d\n", __func__, on);
233 rk29_bl_resume(NULL);
235 rk29_bl_suspend(NULL);
238 EXPORT_SYMBOL(rk29_backlight_set);
241 static int rk29_backlight_probe(struct platform_device *pdev)
244 struct rk29_bl_info *rk29_bl_info = pdev->dev.platform_data;
245 u32 id = rk29_bl_info->pwm_id;
247 unsigned long pwm_clk_rate;
248 struct backlight_properties props;
249 int pre_div = PWM_APB_PRE_DIV;
252 printk(KERN_CRIT "%s: backlight device register has existed \n",
257 if (!rk29_bl_info->delay_ms)
258 rk29_bl_info->delay_ms = 100;
260 if (rk29_bl_info->min_brightness < 0 || rk29_bl_info->min_brightness > BL_STEP)
261 rk29_bl_info->min_brightness = 52;
263 if (rk29_bl_info && rk29_bl_info->io_init) {
264 rk29_bl_info->io_init();
267 if(rk29_bl_info->pre_div > 0)
268 pre_div = rk29_bl_info->pre_div;
270 memset(&props, 0, sizeof(struct backlight_properties));
271 props.type = BACKLIGHT_RAW;
272 props.max_brightness = BL_STEP;
273 rk29_bl = backlight_device_register("rk28_bl", &pdev->dev, rk29_bl_info, &rk29_bl_ops, &props);
275 printk(KERN_CRIT "%s: backlight device register error\n",
280 #if defined(CONFIG_ARCH_RK29)
281 pwm_clk = clk_get(NULL, "pwm");
282 #elif defined(CONFIG_ARCH_RK30) || defined(CONFIG_ARCH_RK2928)
283 if (id == 0 || id == 1)
284 pwm_clk = clk_get(NULL, "pwm01");
285 else if (id == 2 || id == 3)
286 pwm_clk = clk_get(NULL, "pwm23");
288 if (IS_ERR(pwm_clk) || !pwm_clk) {
289 printk(KERN_ERR "failed to get pwm clock source\n");
292 pwm_clk_rate = clk_get_rate(pwm_clk);
293 div_total = pwm_clk_rate / pre_div;
295 div_total >>= (1 + (PWM_DIV >> 9));
296 div_total = (div_total) ? div_total : 1;
298 if(rk29_bl_info->bl_ref) {
305 write_pwm_reg(id, PWM_REG_CTRL, PWM_DIV|PWM_RESET);
306 write_pwm_reg(id, PWM_REG_LRC, div_total);
307 write_pwm_reg(id, PWM_REG_HRC, divh);
308 write_pwm_reg(id, PWM_REG_CNTR, 0x0);
309 write_pwm_reg(id, PWM_REG_CTRL, PWM_DIV|PWM_ENABLE|PWM_TIME_EN);
311 rk29_bl->props.power = FB_BLANK_UNBLANK;
312 rk29_bl->props.fb_blank = FB_BLANK_UNBLANK;
313 rk29_bl->props.brightness = BL_STEP / 2;
314 rk29_bl->props.state = BL_CORE_DRIVER1;
316 schedule_delayed_work(&rk29_backlight_work, msecs_to_jiffies(rk29_bl_info->delay_ms));
317 ret = device_create_file(&pdev->dev,&dev_attr_rk29backlight);
320 dev_err(&pdev->dev, "failed to create sysfs file\n");
323 register_early_suspend(&bl_early_suspend);
325 printk("RK29 Backlight Driver Initialized.\n");
329 static int rk29_backlight_remove(struct platform_device *pdev)
331 struct rk29_bl_info *rk29_bl_info = pdev->dev.platform_data;
334 backlight_device_unregister(rk29_bl);
335 unregister_early_suspend(&bl_early_suspend);
336 clk_disable(pwm_clk);
338 if (rk29_bl_info && rk29_bl_info->io_deinit) {
339 rk29_bl_info->io_deinit();
343 DBG(KERN_CRIT "%s: no backlight device has registered\n",
349 static void rk29_backlight_shutdown(struct platform_device *pdev)
351 struct rk29_bl_info *rk29_bl_info = pdev->dev.platform_data;
353 unregister_early_suspend(&bl_early_suspend);
355 rk29_bl->props.brightness >>= 1;
356 rk29_bl_update_status(rk29_bl);
359 rk29_bl->props.brightness >>= 1;
360 rk29_bl_update_status(rk29_bl);
363 rk29_bl->props.brightness = 0;
364 rk29_bl_update_status(rk29_bl);
366 if (rk29_bl_info && rk29_bl_info->io_deinit)
367 rk29_bl_info->io_deinit();
370 static struct platform_driver rk29_backlight_driver = {
371 .probe = rk29_backlight_probe,
372 .remove = rk29_backlight_remove,
374 .name = "rk29_backlight",
375 .owner = THIS_MODULE,
377 .shutdown = rk29_backlight_shutdown,
380 static int __init rk29_backlight_init(void)
382 platform_driver_register(&rk29_backlight_driver);
385 fs_initcall_sync(rk29_backlight_init);