video: backlight: Add OCP8178 backlight driver
This driver is taken from https://github.com/clockworkpi/DevTerm/blob/main/Code/patch/armbian_build_a06/patch/kernel-005-backlight.patch and optimized for v6.5
This commit is contained in:
ayakael
parent
a45dd3868f
commit
bf1ccb5dc6
3 changed files with 284 additions and 0 deletions
|
|
@ -477,6 +477,12 @@ config BACKLIGHT_LED
|
|||
If you have a LCD backlight adjustable by LED class driver, say Y
|
||||
to enable this driver.
|
||||
|
||||
config BACKLIGHT_OCP8178
|
||||
tristate "OCP8178 Backlight Driver"
|
||||
depends on GPIOLIB
|
||||
help
|
||||
If you have an OCP8178, say Y to enable the backlight driver.
|
||||
|
||||
endif # BACKLIGHT_CLASS_DEVICE
|
||||
|
||||
endmenu
|
||||
|
|
|
|||
|
|
@ -59,3 +59,4 @@ obj-$(CONFIG_BACKLIGHT_WM831X) += wm831x_bl.o
|
|||
obj-$(CONFIG_BACKLIGHT_ARCXCNN) += arcxcnn_bl.o
|
||||
obj-$(CONFIG_BACKLIGHT_RAVE_SP) += rave-sp-backlight.o
|
||||
obj-$(CONFIG_BACKLIGHT_LED) += led_bl.o
|
||||
obj-$(CONFIG_BACKLIGHT_OCP8178) += ocp8178_bl.o
|
||||
|
|
|
|||
277
drivers/video/backlight/ocp8178_bl.c
Normal file
277
drivers/video/backlight/ocp8178_bl.c
Normal file
|
|
@ -0,0 +1,277 @@
|
|||
/*
|
||||
* ocp8178_bl.c - ocp8178 backlight driver
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
|
||||
#include <linux/backlight.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/fb.h>
|
||||
#include <linux/gpio.h> /* Only for legacy support */
|
||||
#include <linux/gpio/consumer.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_data/gpio_backlight.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/timer.h>
|
||||
#include <linux/poll.h>
|
||||
#include <linux/proc_fs.h>
|
||||
#include <linux/seq_file.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/interrupt.h>
|
||||
#include <linux/irq.h>
|
||||
#include <linux/io.h>
|
||||
#include <linux/clk.h>
|
||||
|
||||
struct ocp8178_backlight {
|
||||
struct device *dev;
|
||||
struct device *fbdev;
|
||||
|
||||
struct gpio_desc *gpiod;
|
||||
int def_value;
|
||||
int current_value;
|
||||
};
|
||||
|
||||
#define DETECT_DELAY 200
|
||||
#define DETECT_TIME 500
|
||||
#define DETECT_WINDOW_TIME 1000
|
||||
#define START_TIME 10
|
||||
#define END_TIME 10
|
||||
#define SHUTDOWN_TIME 3000
|
||||
#define LOW_BIT_HIGH_TIME 10
|
||||
#define LOW_BIT_LOW_TIME 50
|
||||
#define HIGH_BIT_HIGH_TIME 50
|
||||
#define HIGH_BIT_LOW_TIME 10
|
||||
#define MAX_BRIGHTNESS_VALUE 9
|
||||
|
||||
static void entry_1wire_mode(struct ocp8178_backlight *gbl)
|
||||
{
|
||||
unsigned long flags = 0;
|
||||
local_irq_save(flags);
|
||||
gpiod_set_value(gbl->gpiod, 0);
|
||||
mdelay(SHUTDOWN_TIME/1000);
|
||||
gpiod_set_value(gbl->gpiod, 1);
|
||||
udelay(DETECT_DELAY);
|
||||
gpiod_set_value(gbl->gpiod, 0);
|
||||
udelay(DETECT_TIME);
|
||||
gpiod_set_value(gbl->gpiod, 1);
|
||||
udelay(DETECT_WINDOW_TIME);
|
||||
local_irq_restore(flags);
|
||||
}
|
||||
|
||||
static inline void write_bit(struct ocp8178_backlight *gbl, int bit)
|
||||
{
|
||||
if (bit) {
|
||||
gpiod_set_value(gbl->gpiod, 0);
|
||||
udelay(HIGH_BIT_LOW_TIME);
|
||||
gpiod_set_value(gbl->gpiod, 1);
|
||||
udelay(HIGH_BIT_HIGH_TIME);
|
||||
} else {
|
||||
gpiod_set_value(gbl->gpiod, 0);
|
||||
udelay(LOW_BIT_LOW_TIME);
|
||||
gpiod_set_value(gbl->gpiod, 1);
|
||||
udelay(LOW_BIT_HIGH_TIME);
|
||||
}
|
||||
}
|
||||
|
||||
static void write_byte(struct ocp8178_backlight *gbl, int byte)
|
||||
{
|
||||
unsigned long flags = 0;
|
||||
unsigned char data = 0x72;
|
||||
int i;
|
||||
|
||||
local_irq_save(flags);
|
||||
|
||||
gpiod_set_value(gbl->gpiod, 1);
|
||||
udelay(START_TIME);
|
||||
for(i = 0; i < 8; i++) {
|
||||
if(data & 0x80) {
|
||||
write_bit(gbl, 1);
|
||||
} else {
|
||||
write_bit(gbl, 0);
|
||||
}
|
||||
data <<= 1;
|
||||
}
|
||||
gpiod_set_value(gbl->gpiod, 0);
|
||||
udelay(END_TIME);
|
||||
|
||||
data = byte & 0x1f;
|
||||
|
||||
gpiod_set_value(gbl->gpiod, 1);
|
||||
udelay(START_TIME);
|
||||
for(i = 0; i < 8; i++) {
|
||||
if(data & 0x80) {
|
||||
write_bit(gbl, 1);
|
||||
} else {
|
||||
write_bit(gbl, 0);
|
||||
}
|
||||
data <<= 1;
|
||||
}
|
||||
gpiod_set_value(gbl->gpiod, 0);
|
||||
udelay(END_TIME);
|
||||
gpiod_set_value(gbl->gpiod, 1);
|
||||
|
||||
local_irq_restore(flags);
|
||||
}
|
||||
|
||||
unsigned char ocp8178_bl_table[MAX_BRIGHTNESS_VALUE+1] = {0, 1, 4, 8, 12, 16, 20, 24, 28, 31};
|
||||
|
||||
static int ocp8178_update_status(struct backlight_device *bl)
|
||||
{
|
||||
struct ocp8178_backlight *gbl = bl_get_data(bl);
|
||||
int brightness = bl->props.brightness, i;
|
||||
|
||||
if (bl->props.power != FB_BLANK_UNBLANK ||
|
||||
bl->props.fb_blank != FB_BLANK_UNBLANK ||
|
||||
bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
|
||||
brightness = 0;
|
||||
|
||||
if(brightness > MAX_BRIGHTNESS_VALUE)
|
||||
brightness = MAX_BRIGHTNESS_VALUE;
|
||||
|
||||
for(i = 0; i < 2; i++) {
|
||||
entry_1wire_mode(gbl);
|
||||
write_byte(gbl, ocp8178_bl_table[brightness]);
|
||||
}
|
||||
gbl->current_value = brightness;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ocp8178_get_brightness(struct backlight_device *bl)
|
||||
{
|
||||
struct ocp8178_backlight *gbl = bl_get_data(bl);
|
||||
return gbl->current_value;
|
||||
}
|
||||
|
||||
static int ocp8178_check_fb(struct backlight_device *bl,
|
||||
struct fb_info *info)
|
||||
{
|
||||
struct ocp8178_backlight *gbl = bl_get_data(bl);
|
||||
return gbl->fbdev == NULL || gbl->fbdev == info->dev;
|
||||
}
|
||||
|
||||
static const struct backlight_ops ocp8178_backlight_ops = {
|
||||
.options = BL_CORE_SUSPENDRESUME,
|
||||
.update_status = ocp8178_update_status,
|
||||
.get_brightness = ocp8178_get_brightness,
|
||||
.check_fb = ocp8178_check_fb,
|
||||
};
|
||||
|
||||
static int ocp8178_probe_dt(struct platform_device *pdev,
|
||||
struct ocp8178_backlight *gbl)
|
||||
{
|
||||
struct device *dev = &pdev->dev;
|
||||
struct device_node *np = dev->of_node;
|
||||
enum gpiod_flags flags;
|
||||
int ret = 0;
|
||||
u32 value32;
|
||||
|
||||
of_property_read_u32(np, "default-brightness", &value32);
|
||||
if(value32 > MAX_BRIGHTNESS_VALUE)
|
||||
gbl->def_value = MAX_BRIGHTNESS_VALUE;
|
||||
else
|
||||
gbl->def_value = value32;
|
||||
flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
|
||||
|
||||
gbl->gpiod = devm_gpiod_get(dev, "backlight-control", flags);
|
||||
if (IS_ERR(gbl->gpiod)) {
|
||||
ret = PTR_ERR(gbl->gpiod);
|
||||
|
||||
if (ret != -EPROBE_DEFER) {
|
||||
dev_err(dev,
|
||||
"Error: The gpios parameter is missing or invalid.\n");
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static struct backlight_device *backlight;
|
||||
|
||||
static int ocp8178_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct backlight_properties props;
|
||||
struct backlight_device *bl;
|
||||
struct ocp8178_backlight *gbl;
|
||||
struct device_node *np = pdev->dev.of_node;
|
||||
int ret;
|
||||
|
||||
if ( !np) {
|
||||
dev_err(&pdev->dev,
|
||||
"failed to find platform data or device tree node.\n");
|
||||
return -ENODEV;
|
||||
}
|
||||
|
||||
gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
|
||||
if (gbl == NULL)
|
||||
return -ENOMEM;
|
||||
|
||||
gbl->dev = &pdev->dev;
|
||||
|
||||
ret = ocp8178_probe_dt(pdev, gbl);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
gbl->current_value = gbl->def_value;
|
||||
|
||||
memset(&props, 0, sizeof(props));
|
||||
props.type = BACKLIGHT_RAW;
|
||||
props.max_brightness = MAX_BRIGHTNESS_VALUE;
|
||||
bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev),
|
||||
&pdev->dev, gbl, &ocp8178_backlight_ops,
|
||||
&props);
|
||||
if (IS_ERR(bl)) {
|
||||
dev_err(&pdev->dev, "failed to register backlight\n");
|
||||
return PTR_ERR(bl);
|
||||
}
|
||||
|
||||
// entry_1wire_mode(gbl);
|
||||
|
||||
bl->props.brightness = gbl->def_value;
|
||||
backlight_update_status(bl);
|
||||
|
||||
platform_set_drvdata(pdev, bl);
|
||||
|
||||
backlight = bl;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ocp8178_suspend(struct platform_device *pdev, pm_message_t state)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ocp8178_resume(struct platform_device *pdev)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct of_device_id ocp8178_of_match[] = {
|
||||
{ .compatible = "ocp8178-backlight" },
|
||||
{ /* sentinel */ }
|
||||
};
|
||||
|
||||
MODULE_DEVICE_TABLE(of, ocp8178_of_match);
|
||||
|
||||
static struct platform_driver ocp8178_driver = {
|
||||
.driver = {
|
||||
.name = "ocp8178-backlight",
|
||||
.of_match_table = of_match_ptr(ocp8178_of_match),
|
||||
},
|
||||
.probe = ocp8178_probe,
|
||||
.suspend = ocp8178_suspend,
|
||||
.resume = ocp8178_resume,
|
||||
};
|
||||
|
||||
module_platform_driver(ocp8178_driver);
|
||||
|
||||
MODULE_DESCRIPTION("OCP8178 Driver");
|
||||
MODULE_LICENSE("GPL");
|
||||
Loading…
Add table
Add a link
Reference in a new issue