355 lines
9.0 KiB
C
355 lines
9.0 KiB
C
|
/*
|
||
|
|
* sky81452-backlight.c SKY81452 backlight driver
|
||
|
|
*
|
||
|
|
* Copyright 2014 Skyworks Solutions Inc.
|
||
|
|
* Author : Gyungoh Yoo <jack.yoo@skyworksinc.com>
|
||
|
|
*
|
||
|
|
* 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 (ret < 0)
|
||
|
|
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 const struct backlight_ops sky81452_bl_ops = {
|
||
|
|
.update_status = sky81452_bl_update_status,
|
||
|
|
};
|
||
|
|
|
||
|
|
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 (ret < 0)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
ret = regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN,
|
||
|
|
value << CTZ(SKY81452_EN));
|
||
|
|
if (ret < 0)
|
||
|
|
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 (ret < 0)
|
||
|
|
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 (ret < 0)
|
||
|
|
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 num_entry;
|
||
|
|
unsigned int sources[6];
|
||
|
|
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, "skyworks,ignore-pwm");
|
||
|
|
pdata->dpwm_mode = of_property_read_bool(np, "skyworks,dpwm-mode");
|
||
|
|
pdata->phase_shift = of_property_read_bool(np, "skyworks,phase-shift");
|
||
|
|
pdata->gpio_enable = of_get_gpio(np, 0);
|
||
|
|
|
||
|
|
ret = of_property_count_u32_elems(np, "led-sources");
|
||
|
|
if (ret < 0) {
|
||
|
|
pdata->enable = SKY81452_EN >> CTZ(SKY81452_EN);
|
||
|
|
} else {
|
||
|
|
num_entry = ret;
|
||
|
|
if (num_entry > 6)
|
||
|
|
num_entry = 6;
|
||
|
|
|
||
|
|
ret = of_property_read_u32_array(np, "led-sources", sources,
|
||
|
|
num_entry);
|
||
|
|
if (ret < 0) {
|
||
|
|
dev_err(dev, "led-sources node is invalid.\n");
|
||
|
|
of_node_put(np);
|
||
|
|
return ERR_PTR(-EINVAL);
|
||
|
|
}
|
||
|
|
|
||
|
|
pdata->enable = 0;
|
||
|
|
while (--num_entry)
|
||
|
|
pdata->enable |= (1 << sources[num_entry]);
|
||
|
|
}
|
||
|
|
|
||
|
|
ret = of_property_read_u32(np,
|
||
|
|
"skyworks,short-detection-threshold-volt",
|
||
|
|
&pdata->short_detection_threshold);
|
||
|
|
if (ret < 0)
|
||
|
|
pdata->short_detection_threshold = 7;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(np, "skyworks,current-limit-mA",
|
||
|
|
&pdata->boost_current_limit);
|
||
|
|
if (ret < 0)
|
||
|
|
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 != 2750)
|
||
|
|
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 (gpio_is_valid(pdata->gpio_enable)) {
|
||
|
|
ret = devm_gpio_request_one(dev, pdata->gpio_enable,
|
||
|
|
GPIOF_OUT_INIT_HIGH, "sky81452-en");
|
||
|
|
if (ret < 0) {
|
||
|
|
dev_err(dev, "failed to request GPIO. err=%d\n", ret);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
ret = sky81452_bl_init_device(regmap, pdata);
|
||
|
|
if (ret < 0) {
|
||
|
|
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 (ret < 0) {
|
||
|
|
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 (gpio_is_valid(pdata->gpio_enable))
|
||
|
|
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@skyworksinc.com>");
|
||
|
|
MODULE_LICENSE("GPL v2");
|