420 lines
11 KiB
C
420 lines
11 KiB
C
|
/*
|
||
|
|
* Backlight driver for ArcticSand ARC_X_C_0N_0N Devices
|
||
|
|
*
|
||
|
|
* Copyright 2016 ArcticSand, Inc.
|
||
|
|
* Author : Brian Dodge <bdodge@arcticsand.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/i2c.h>
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/of.h>
|
||
|
|
#include <linux/slab.h>
|
||
|
|
|
||
|
|
enum arcxcnn_chip_id {
|
||
|
|
ARC2C0608
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* struct arcxcnn_platform_data
|
||
|
|
* @name : Backlight driver name (NULL will use default)
|
||
|
|
* @initial_brightness : initial value of backlight brightness
|
||
|
|
* @leden : initial LED string enables, upper bit is global on/off
|
||
|
|
* @led_config_0 : fading speed (period between intensity steps)
|
||
|
|
* @led_config_1 : misc settings, see datasheet
|
||
|
|
* @dim_freq : pwm dimming frequency if in pwm mode
|
||
|
|
* @comp_config : misc config, see datasheet
|
||
|
|
* @filter_config : RC/PWM filter config, see datasheet
|
||
|
|
* @trim_config : full scale current trim, see datasheet
|
||
|
|
*/
|
||
|
|
struct arcxcnn_platform_data {
|
||
|
|
const char *name;
|
||
|
|
u16 initial_brightness;
|
||
|
|
u8 leden;
|
||
|
|
u8 led_config_0;
|
||
|
|
u8 led_config_1;
|
||
|
|
u8 dim_freq;
|
||
|
|
u8 comp_config;
|
||
|
|
u8 filter_config;
|
||
|
|
u8 trim_config;
|
||
|
|
};
|
||
|
|
|
||
|
|
#define ARCXCNN_CMD 0x00 /* Command Register */
|
||
|
|
#define ARCXCNN_CMD_STDBY 0x80 /* I2C Standby */
|
||
|
|
#define ARCXCNN_CMD_RESET 0x40 /* Reset */
|
||
|
|
#define ARCXCNN_CMD_BOOST 0x10 /* Boost */
|
||
|
|
#define ARCXCNN_CMD_OVP_MASK 0x0C /* --- Over Voltage Threshold */
|
||
|
|
#define ARCXCNN_CMD_OVP_XXV 0x0C /* <rsvrd> Over Voltage Threshold */
|
||
|
|
#define ARCXCNN_CMD_OVP_20V 0x08 /* 20v Over Voltage Threshold */
|
||
|
|
#define ARCXCNN_CMD_OVP_24V 0x04 /* 24v Over Voltage Threshold */
|
||
|
|
#define ARCXCNN_CMD_OVP_31V 0x00 /* 31.4v Over Voltage Threshold */
|
||
|
|
#define ARCXCNN_CMD_EXT_COMP 0x01 /* part (0) or full (1) ext. comp */
|
||
|
|
|
||
|
|
#define ARCXCNN_CONFIG 0x01 /* Configuration */
|
||
|
|
#define ARCXCNN_STATUS1 0x02 /* Status 1 */
|
||
|
|
#define ARCXCNN_STATUS2 0x03 /* Status 2 */
|
||
|
|
#define ARCXCNN_FADECTRL 0x04 /* Fading Control */
|
||
|
|
#define ARCXCNN_ILED_CONFIG 0x05 /* ILED Configuration */
|
||
|
|
#define ARCXCNN_ILED_DIM_PWM 0x00 /* config dim mode pwm */
|
||
|
|
#define ARCXCNN_ILED_DIM_INT 0x04 /* config dim mode internal */
|
||
|
|
#define ARCXCNN_LEDEN 0x06 /* LED Enable Register */
|
||
|
|
#define ARCXCNN_LEDEN_ISETEXT 0x80 /* Full-scale current set extern */
|
||
|
|
#define ARCXCNN_LEDEN_MASK 0x3F /* LED string enables mask */
|
||
|
|
#define ARCXCNN_LEDEN_BITS 0x06 /* Bits of LED string enables */
|
||
|
|
#define ARCXCNN_LEDEN_LED1 0x01
|
||
|
|
#define ARCXCNN_LEDEN_LED2 0x02
|
||
|
|
#define ARCXCNN_LEDEN_LED3 0x04
|
||
|
|
#define ARCXCNN_LEDEN_LED4 0x08
|
||
|
|
#define ARCXCNN_LEDEN_LED5 0x10
|
||
|
|
#define ARCXCNN_LEDEN_LED6 0x20
|
||
|
|
|
||
|
|
#define ARCXCNN_WLED_ISET_LSB 0x07 /* LED ISET LSB (in upper nibble) */
|
||
|
|
#define ARCXCNN_WLED_ISET_LSB_SHIFT 0x04 /* ISET LSB Left Shift */
|
||
|
|
#define ARCXCNN_WLED_ISET_MSB 0x08 /* LED ISET MSB (8 bits) */
|
||
|
|
|
||
|
|
#define ARCXCNN_DIMFREQ 0x09
|
||
|
|
#define ARCXCNN_COMP_CONFIG 0x0A
|
||
|
|
#define ARCXCNN_FILT_CONFIG 0x0B
|
||
|
|
#define ARCXCNN_IMAXTUNE 0x0C
|
||
|
|
#define ARCXCNN_ID_MSB 0x1E
|
||
|
|
#define ARCXCNN_ID_LSB 0x1F
|
||
|
|
|
||
|
|
#define MAX_BRIGHTNESS 4095
|
||
|
|
#define INIT_BRIGHT 60
|
||
|
|
|
||
|
|
struct arcxcnn {
|
||
|
|
struct i2c_client *client;
|
||
|
|
struct backlight_device *bl;
|
||
|
|
struct device *dev;
|
||
|
|
struct arcxcnn_platform_data *pdata;
|
||
|
|
};
|
||
|
|
|
||
|
|
static int arcxcnn_update_field(struct arcxcnn *lp, u8 reg, u8 mask, u8 data)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
u8 tmp;
|
||
|
|
|
||
|
|
ret = i2c_smbus_read_byte_data(lp->client, reg);
|
||
|
|
if (ret < 0) {
|
||
|
|
dev_err(lp->dev, "failed to read 0x%.2x\n", reg);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
tmp = (u8)ret;
|
||
|
|
tmp &= ~mask;
|
||
|
|
tmp |= data & mask;
|
||
|
|
|
||
|
|
return i2c_smbus_write_byte_data(lp->client, reg, tmp);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int arcxcnn_set_brightness(struct arcxcnn *lp, u32 brightness)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
u8 val;
|
||
|
|
|
||
|
|
/* lower nibble of brightness goes in upper nibble of LSB register */
|
||
|
|
val = (brightness & 0xF) << ARCXCNN_WLED_ISET_LSB_SHIFT;
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client,
|
||
|
|
ARCXCNN_WLED_ISET_LSB, val);
|
||
|
|
if (ret < 0)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* remaining 8 bits of brightness go in MSB register */
|
||
|
|
val = (brightness >> 4);
|
||
|
|
return i2c_smbus_write_byte_data(lp->client,
|
||
|
|
ARCXCNN_WLED_ISET_MSB, val);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int arcxcnn_bl_update_status(struct backlight_device *bl)
|
||
|
|
{
|
||
|
|
struct arcxcnn *lp = bl_get_data(bl);
|
||
|
|
u32 brightness = bl->props.brightness;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
if (bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
|
||
|
|
brightness = 0;
|
||
|
|
|
||
|
|
ret = arcxcnn_set_brightness(lp, brightness);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* set power-on/off/save modes */
|
||
|
|
return arcxcnn_update_field(lp, ARCXCNN_CMD, ARCXCNN_CMD_STDBY,
|
||
|
|
(bl->props.power == 0) ? 0 : ARCXCNN_CMD_STDBY);
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct backlight_ops arcxcnn_bl_ops = {
|
||
|
|
.options = BL_CORE_SUSPENDRESUME,
|
||
|
|
.update_status = arcxcnn_bl_update_status,
|
||
|
|
};
|
||
|
|
|
||
|
|
static int arcxcnn_backlight_register(struct arcxcnn *lp)
|
||
|
|
{
|
||
|
|
struct backlight_properties *props;
|
||
|
|
const char *name = lp->pdata->name ? : "arctic_bl";
|
||
|
|
|
||
|
|
props = devm_kzalloc(lp->dev, sizeof(*props), GFP_KERNEL);
|
||
|
|
if (!props)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
props->type = BACKLIGHT_PLATFORM;
|
||
|
|
props->max_brightness = MAX_BRIGHTNESS;
|
||
|
|
|
||
|
|
if (lp->pdata->initial_brightness > props->max_brightness)
|
||
|
|
lp->pdata->initial_brightness = props->max_brightness;
|
||
|
|
|
||
|
|
props->brightness = lp->pdata->initial_brightness;
|
||
|
|
|
||
|
|
lp->bl = devm_backlight_device_register(lp->dev, name, lp->dev, lp,
|
||
|
|
&arcxcnn_bl_ops, props);
|
||
|
|
return PTR_ERR_OR_ZERO(lp->bl);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void arcxcnn_parse_dt(struct arcxcnn *lp)
|
||
|
|
{
|
||
|
|
struct device *dev = lp->dev;
|
||
|
|
struct device_node *node = dev->of_node;
|
||
|
|
u32 prog_val, num_entry, entry, sources[ARCXCNN_LEDEN_BITS];
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
/* device tree entry isn't required, defaults are OK */
|
||
|
|
if (!node)
|
||
|
|
return;
|
||
|
|
|
||
|
|
ret = of_property_read_string(node, "label", &lp->pdata->name);
|
||
|
|
if (ret < 0)
|
||
|
|
lp->pdata->name = NULL;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(node, "default-brightness", &prog_val);
|
||
|
|
if (ret == 0)
|
||
|
|
lp->pdata->initial_brightness = prog_val;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(node, "arc,led-config-0", &prog_val);
|
||
|
|
if (ret == 0)
|
||
|
|
lp->pdata->led_config_0 = (u8)prog_val;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(node, "arc,led-config-1", &prog_val);
|
||
|
|
if (ret == 0)
|
||
|
|
lp->pdata->led_config_1 = (u8)prog_val;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(node, "arc,dim-freq", &prog_val);
|
||
|
|
if (ret == 0)
|
||
|
|
lp->pdata->dim_freq = (u8)prog_val;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(node, "arc,comp-config", &prog_val);
|
||
|
|
if (ret == 0)
|
||
|
|
lp->pdata->comp_config = (u8)prog_val;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(node, "arc,filter-config", &prog_val);
|
||
|
|
if (ret == 0)
|
||
|
|
lp->pdata->filter_config = (u8)prog_val;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(node, "arc,trim-config", &prog_val);
|
||
|
|
if (ret == 0)
|
||
|
|
lp->pdata->trim_config = (u8)prog_val;
|
||
|
|
|
||
|
|
ret = of_property_count_u32_elems(node, "led-sources");
|
||
|
|
if (ret < 0) {
|
||
|
|
lp->pdata->leden = ARCXCNN_LEDEN_MASK; /* all on is default */
|
||
|
|
} else {
|
||
|
|
num_entry = ret;
|
||
|
|
if (num_entry > ARCXCNN_LEDEN_BITS)
|
||
|
|
num_entry = ARCXCNN_LEDEN_BITS;
|
||
|
|
|
||
|
|
ret = of_property_read_u32_array(node, "led-sources", sources,
|
||
|
|
num_entry);
|
||
|
|
if (ret < 0) {
|
||
|
|
dev_err(dev, "led-sources node is invalid.\n");
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
lp->pdata->leden = 0;
|
||
|
|
|
||
|
|
/* for each enable in source, set bit in led enable */
|
||
|
|
for (entry = 0; entry < num_entry; entry++) {
|
||
|
|
u8 onbit = 1 << sources[entry];
|
||
|
|
|
||
|
|
lp->pdata->leden |= onbit;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static int arcxcnn_probe(struct i2c_client *cl, const struct i2c_device_id *id)
|
||
|
|
{
|
||
|
|
struct arcxcnn *lp;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
if (!i2c_check_functionality(cl->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
|
||
|
|
return -EIO;
|
||
|
|
|
||
|
|
lp = devm_kzalloc(&cl->dev, sizeof(*lp), GFP_KERNEL);
|
||
|
|
if (!lp)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
lp->client = cl;
|
||
|
|
lp->dev = &cl->dev;
|
||
|
|
lp->pdata = dev_get_platdata(&cl->dev);
|
||
|
|
|
||
|
|
/* reset the device */
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client,
|
||
|
|
ARCXCNN_CMD, ARCXCNN_CMD_RESET);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
if (!lp->pdata) {
|
||
|
|
lp->pdata = devm_kzalloc(lp->dev,
|
||
|
|
sizeof(*lp->pdata), GFP_KERNEL);
|
||
|
|
if (!lp->pdata)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
/* Setup defaults based on power-on defaults */
|
||
|
|
lp->pdata->name = NULL;
|
||
|
|
lp->pdata->initial_brightness = INIT_BRIGHT;
|
||
|
|
lp->pdata->leden = ARCXCNN_LEDEN_MASK;
|
||
|
|
|
||
|
|
lp->pdata->led_config_0 = i2c_smbus_read_byte_data(
|
||
|
|
lp->client, ARCXCNN_FADECTRL);
|
||
|
|
|
||
|
|
lp->pdata->led_config_1 = i2c_smbus_read_byte_data(
|
||
|
|
lp->client, ARCXCNN_ILED_CONFIG);
|
||
|
|
/* insure dim mode is not default pwm */
|
||
|
|
lp->pdata->led_config_1 |= ARCXCNN_ILED_DIM_INT;
|
||
|
|
|
||
|
|
lp->pdata->dim_freq = i2c_smbus_read_byte_data(
|
||
|
|
lp->client, ARCXCNN_DIMFREQ);
|
||
|
|
|
||
|
|
lp->pdata->comp_config = i2c_smbus_read_byte_data(
|
||
|
|
lp->client, ARCXCNN_COMP_CONFIG);
|
||
|
|
|
||
|
|
lp->pdata->filter_config = i2c_smbus_read_byte_data(
|
||
|
|
lp->client, ARCXCNN_FILT_CONFIG);
|
||
|
|
|
||
|
|
lp->pdata->trim_config = i2c_smbus_read_byte_data(
|
||
|
|
lp->client, ARCXCNN_IMAXTUNE);
|
||
|
|
|
||
|
|
if (IS_ENABLED(CONFIG_OF))
|
||
|
|
arcxcnn_parse_dt(lp);
|
||
|
|
}
|
||
|
|
|
||
|
|
i2c_set_clientdata(cl, lp);
|
||
|
|
|
||
|
|
/* constrain settings to what is possible */
|
||
|
|
if (lp->pdata->initial_brightness > MAX_BRIGHTNESS)
|
||
|
|
lp->pdata->initial_brightness = MAX_BRIGHTNESS;
|
||
|
|
|
||
|
|
/* set initial brightness */
|
||
|
|
ret = arcxcnn_set_brightness(lp, lp->pdata->initial_brightness);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
/* set other register values directly */
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client, ARCXCNN_FADECTRL,
|
||
|
|
lp->pdata->led_config_0);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client, ARCXCNN_ILED_CONFIG,
|
||
|
|
lp->pdata->led_config_1);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client, ARCXCNN_DIMFREQ,
|
||
|
|
lp->pdata->dim_freq);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client, ARCXCNN_COMP_CONFIG,
|
||
|
|
lp->pdata->comp_config);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client, ARCXCNN_FILT_CONFIG,
|
||
|
|
lp->pdata->filter_config);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
ret = i2c_smbus_write_byte_data(lp->client, ARCXCNN_IMAXTUNE,
|
||
|
|
lp->pdata->trim_config);
|
||
|
|
if (ret)
|
||
|
|
goto probe_err;
|
||
|
|
|
||
|
|
/* set initial LED Enables */
|
||
|
|
arcxcnn_update_field(lp, ARCXCNN_LEDEN,
|
||
|
|
ARCXCNN_LEDEN_MASK, lp->pdata->leden);
|
||
|
|
|
||
|
|
ret = arcxcnn_backlight_register(lp);
|
||
|
|
if (ret)
|
||
|
|
goto probe_register_err;
|
||
|
|
|
||
|
|
backlight_update_status(lp->bl);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
probe_register_err:
|
||
|
|
dev_err(lp->dev,
|
||
|
|
"failed to register backlight.\n");
|
||
|
|
|
||
|
|
probe_err:
|
||
|
|
dev_err(lp->dev,
|
||
|
|
"failure ret: %d\n", ret);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int arcxcnn_remove(struct i2c_client *cl)
|
||
|
|
{
|
||
|
|
struct arcxcnn *lp = i2c_get_clientdata(cl);
|
||
|
|
|
||
|
|
/* disable all strings (ignore errors) */
|
||
|
|
i2c_smbus_write_byte_data(lp->client,
|
||
|
|
ARCXCNN_LEDEN, 0x00);
|
||
|
|
/* reset the device (ignore errors) */
|
||
|
|
i2c_smbus_write_byte_data(lp->client,
|
||
|
|
ARCXCNN_CMD, ARCXCNN_CMD_RESET);
|
||
|
|
|
||
|
|
lp->bl->props.brightness = 0;
|
||
|
|
|
||
|
|
backlight_update_status(lp->bl);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct of_device_id arcxcnn_dt_ids[] = {
|
||
|
|
{ .compatible = "arc,arc2c0608" },
|
||
|
|
{ }
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(of, arcxcnn_dt_ids);
|
||
|
|
|
||
|
|
static const struct i2c_device_id arcxcnn_ids[] = {
|
||
|
|
{"arc2c0608", ARC2C0608},
|
||
|
|
{ }
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(i2c, arcxcnn_ids);
|
||
|
|
|
||
|
|
static struct i2c_driver arcxcnn_driver = {
|
||
|
|
.driver = {
|
||
|
|
.name = "arcxcnn_bl",
|
||
|
|
.of_match_table = of_match_ptr(arcxcnn_dt_ids),
|
||
|
|
},
|
||
|
|
.probe = arcxcnn_probe,
|
||
|
|
.remove = arcxcnn_remove,
|
||
|
|
.id_table = arcxcnn_ids,
|
||
|
|
};
|
||
|
|
module_i2c_driver(arcxcnn_driver);
|
||
|
|
|
||
|
|
MODULE_LICENSE("GPL v2");
|
||
|
|
MODULE_AUTHOR("Brian Dodge <bdodge@arcticsand.com>");
|
||
|
|
MODULE_DESCRIPTION("ARCXCNN Backlight driver");
|