Re: [PATCH] backlight: add new lm3509 backlight driver

From: Jingoo Han
Date: Mon Sep 15 2014 - 02:47:48 EST

Next message: Johannes Thumshirn: "[PATCH v2] tty: serial: men_z135_uart: Fix driver for changes in hardware"
Previous message: Andreas Werner: "[PATCH] MAINTAINERS: Adds Andreas Werner to maintainers list for MEN F21BMC"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On Friday, August 29, 2014 7:46 PM, Daniel Jeong wrote:
>
> This is a general driver for LM3509 backlgiht chip of TI.
> LM3509 is High Efficiency Boost for White LED's and/or OLED Displays with Dual
> Current Sinks. This driver supports OLED/White LED select, brightness control
> sub/main conrtorl.
> You can refer to the datasheet at http://www.ti.com/product/lm3509 for review.
>
> Signed-off-by: Daniel Jeong <gshark.jeong@xxxxxxxxx>
> ---
> drivers/video/backlight/Kconfig | 7 +
> drivers/video/backlight/Makefile | 1 +
> drivers/video/backlight/lm3509_bl.c | 399 +++++++++++++++++++++++++++++++++++
> 3 files changed, 407 insertions(+)
> create mode 100644 drivers/video/backlight/lm3509_bl.c
>
> diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
> index 8d03924..9dc119e 100644
> --- a/drivers/video/backlight/Kconfig
> +++ b/drivers/video/backlight/Kconfig
> @@ -366,6 +366,13 @@ config BACKLIGHT_AAT2870
> If you have a AnalogicTech AAT2870 say Y to enable the
> backlight driver.
>
> +config BACKLIGHT_LM3509
> + tristate "Backlight Driver for LM3509"
> + depends on BACKLIGHT_CLASS_DEVICE && I2C
> + select REGMAP_I2C
> + help
> + This supports TI LM3509 Backlight Driver
> +
> config BACKLIGHT_LM3630A
> tristate "Backlight Driver for LM3630A"
> depends on BACKLIGHT_CLASS_DEVICE && I2C && PWM
> diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
> index fcd50b73..c34ed98 100644
> --- a/drivers/video/backlight/Makefile
> +++ b/drivers/video/backlight/Makefile
> @@ -36,6 +36,7 @@ obj-$(CONFIG_BACKLIGHT_GPIO) += gpio_backlight.o
> obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o
> obj-$(CONFIG_BACKLIGHT_HP700) += jornada720_bl.o
> obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO) += ipaq_micro_bl.o
> +obj-$(CONFIG_BACKLIGHT_LM3509) += lm3509_bl.o
> obj-$(CONFIG_BACKLIGHT_LM3533) += lm3533_bl.o
> obj-$(CONFIG_BACKLIGHT_LM3630A) += lm3630a_bl.o
> obj-$(CONFIG_BACKLIGHT_LM3639) += lm3639_bl.o
> diff --git a/drivers/video/backlight/lm3509_bl.c b/drivers/video/backlight/lm3509_bl.c
> new file mode 100644
> index 0000000..4f4fb85
> --- /dev/null
> +++ b/drivers/video/backlight/lm3509_bl.c
> @@ -0,0 +1,399 @@
> +/*
> + * Simple driver for Texas Instruments LM3509 Backlight driver chip
> + * Copyright (C) 2014 Texas Instruments
> + *
> + * 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/delay.h>
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <linux/uaccess.h>
> +
> +#define LM3509_NAME "lm3509"
> +
> +#define REG_GP 0x10
> +#define REG_BMAIN 0xa0
> +#define REG_BSUB 0xb0
> +#define REG_MAX 0xff

Please keep the same tab spaces for the readability as follows.

+#define REG_GP 0x10
+#define REG_BMAIN 0xa0
+#define REG_BSUB 0xb0
+#define REG_MAX 0xff

> +
> +#define LM3509_POR_BR_MAIN 0xe0
> +#define LM3509_POR_BR_SUB 0xe0
> +#define LM3509_MAX_BR 0xff

> +
> +enum lm3509_leds {
> + BLED_BMAIN = 0,
> + BLED_BSUB
> +};
> +
> +struct lm3509_chip {
> + struct device *dev;
> + struct backlight_device *bmain;
> + struct backlight_device *bsub;
> + struct regmap *regmap;
> +};
> +
> +/*
> + * enable main
> + * 0 : disables the main current sink and forces MAIN high impedence.
> + * 1 : enables the main current sink.
> + */
> +static ssize_t lm3509_bmain_enable_store(struct device *dev,
> + struct device_attribute *devAttr,
> + const char *buf, size_t size)
> +{
> + struct lm3509_chip *pchip = dev_get_drvdata(dev);
> + unsigned int state;
> + ssize_t ret;
> +
> + ret = kstrtouint(buf, 10, &state);
> + if (ret) {
> + dev_err(pchip->dev, "input conversion fail\n");
> + return ret;
> + }
> +
> + if (!state)
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x1, 0x0);
> + else
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x1, 0x1);
> + if (ret < 0) {
> + dev_err(pchip->dev, "i2c access fail to register\n");
> + return ret;
> + }
> +
> + return size;
> +}
> +
> +static DEVICE_ATTR(main_enable, S_IWUSR, NULL, lm3509_bmain_enable_store);
> +
> +/*
> + * OLED mode control
> + * 0 : white led mode - main and sub current sinks are active
> + * 1 : OLED mode - sub current sink is idabled
> + */
> +static ssize_t lm3509_oled_mode_store(struct device *dev,
> + struct device_attribute *devAttr,
> + const char *buf, size_t size)
> +{
> + struct lm3509_chip *pchip = dev_get_drvdata(dev);
> + unsigned int state;
> + ssize_t ret;
> +
> + ret = kstrtouint(buf, 10, &state);
> + if (ret) {
> + dev_err(pchip->dev, "input conversion fail\n");
> + return ret;
> + }
> +
> + if (!state)
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x20, 0x00);
> + else
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x20, 0x20);
> + if (ret < 0) {
> + dev_err(pchip->dev, "i2c access fail to register\n");
> + return ret;
> + }
> +
> + return size;
> +}
> +
> +static DEVICE_ATTR(oled_enable, S_IWUSR, NULL, lm3509_oled_mode_store);
> +
> +/*
> + * brightness rate of change
> + * set the rate of change of the LED current in to MAIN and SUB/FB
> + * in response to change in the contents of registers
> + * 0 - 51 us/step
> + * 1 - 13 ms/step
> + * 2 - 26 ms/step
> + * 3 - 52 ms/step
> + */
> +static ssize_t lm3509_rate_store(struct device *dev,
> + struct device_attribute *devAttr,
> + const char *buf, size_t size)
> +{
> + struct lm3509_chip *pchip = dev_get_drvdata(dev);
> + unsigned int state;
> + ssize_t ret;
> +
> + ret = kstrtouint(buf, 10, &state);
> + if (ret) {
> + dev_err(pchip->dev, "input conversion fail\n");
> + return ret;
> + }
> +
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x18, state << 3);
> + if (ret < 0) {
> + dev_err(pchip->dev, "i2c access fail to register\n");
> + return ret;
> + }
> +
> + return size;
> +}
> +
> +static DEVICE_ATTR(rate, S_IWUSR, NULL, lm3509_rate_store);
> +
> +/* update and get brightness */
> +static int lm3509_bmain_update_status(struct backlight_device *bl)
> +{
> + struct lm3509_chip *pchip = bl_get_data(bl);
> + int ret;
> +
> + ret = regmap_write(pchip->regmap, REG_BMAIN, bl->props.brightness);
> + if (ret < 0)
> + dev_err(pchip->dev, "i2c access fail to register\n");
> + return bl->props.brightness;
> +}
> +
> +static int lm3509_bmain_get_brightness(struct backlight_device *bl)
> +{
> + return bl->props.brightness;
> +}
> +
> +static const struct backlight_ops lm3509_bmain_ops = {
> + .options = BL_CORE_SUSPENDRESUME,
> + .update_status = lm3509_bmain_update_status,
> + .get_brightness = lm3509_bmain_get_brightness,

Please don't add 'lm3509_bmain_get_brightness' callback function,
when it just returns 'props.brightness'.

Please refer to the following links.

http://www.spinics.net/lists/arm-kernel/msg335952.html
http://www.spinics.net/lists/arm-kernel/msg335951.html

> +};
> +
> +/*
> + * enable sub
> + * 0 : disables the secondary current sink and forces SUB/FB high impedence.
> + * 1 : enables the secondary current sink.
> + */
> +static ssize_t lm3509_bsub_enable_store(struct device *dev,
> + struct device_attribute *devAttr,
> + const char *buf, size_t size)
> +{
> + struct lm3509_chip *pchip = dev_get_drvdata(dev);
> + unsigned int state;
> + ssize_t ret;
> +
> + ret = kstrtouint(buf, 10, &state);
> + if (ret) {
> + dev_err(pchip->dev, "input conversion fail\n");
> + return ret;
> + }
> +
> + if (!state)
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x2, 0x0);
> + else
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x2, 0x2);
> + if (ret < 0) {
> + dev_err(pchip->dev, "i2c access fail to register\n");
> + return ret;
> + }
> +
> + return size;
> +}
> +
> +static DEVICE_ATTR(sub_enable, S_IWUSR, NULL, lm3509_bsub_enable_store);
> +
> +/*
> + * uni mode select
> + * 0 : allows the current into MAIN and SUB/FB to be independently controlled
> + * via the bmain and bsub.
> + * 1 : disables the bsub register and causes the contents of bmain to set
> + * the current in both the MAIN and SUB/FB current sinks.
> + */
> +static ssize_t lm3509_uni_mode_store(struct device *dev,
> + struct device_attribute *devAttr,
> + const char *buf, size_t size)
> +{
> + struct lm3509_chip *pchip = dev_get_drvdata(dev);
> + unsigned int state;
> + ssize_t ret;
> +
> + ret = kstrtouint(buf, 10, &state);
> + if (ret) {
> + dev_err(pchip->dev, "input conversion fail\n");
> + return ret;
> + }
> +
> + if (!state)
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x4, 0x0);
> + else
> + ret = regmap_update_bits(pchip->regmap, REG_GP, 0x4, 0x4);
> + if (ret < 0) {
> + dev_err(pchip->dev, "i2c access fail to register\n");
> + return ret;
> + }
> +
> + return size;
> +}
> +
> +static DEVICE_ATTR(uni_mode, S_IWUSR, NULL, lm3509_uni_mode_store);
> +
> +/* update and get brightness */
> +static int lm3509_bsub_update_status(struct backlight_device *bl)
> +{
> + struct lm3509_chip *pchip = bl_get_data(bl);
> + int ret;
> +
> + ret = regmap_write(pchip->regmap, REG_BSUB, bl->props.brightness);
> + if (ret < 0)
> + dev_err(pchip->dev, "i2c access fail to register\n");
> + return bl->props.brightness;
> +}
> +
> +static int lm3509_bsub_get_brightness(struct backlight_device *bl)
> +{
> + return bl->props.brightness;
> +}
> +
> +static const struct backlight_ops lm3509_bsub_ops = {
> + .options = BL_CORE_SUSPENDRESUME,
> + .update_status = lm3509_bsub_update_status,
> + .get_brightness = lm3509_bsub_get_brightness,
> +};

Ditto.

Please don't add 'lm3509_bsub_get_brightness' callback function,
when it just returns 'props.brightness'.

Best regards,
Jingoo Han

> +
> +static int lm3509_backlight_register(struct lm3509_chip *pchip,
> + enum lm3509_leds ledno)
> +{
> + struct backlight_properties props;
> +
> + props.type = BACKLIGHT_RAW;
> + switch (ledno) {
> + case BLED_BMAIN:
> + props.brightness = LM3509_POR_BR_MAIN;
> + props.max_brightness = LM3509_MAX_BR;
> + pchip->bmain =
> + devm_backlight_device_register(pchip->dev, "bmain",
> + pchip->dev, pchip, &lm3509_bmain_ops, &props);
> + if (IS_ERR(pchip->bmain))
> + return -EIO;
> + break;
> + case BLED_BSUB:
> + props.brightness = LM3509_POR_BR_SUB;
> + props.max_brightness = LM3509_MAX_BR;
> + pchip->bsub =
> + devm_backlight_device_register(pchip->dev, "bsub",
> + pchip->dev, pchip, &lm3509_bsub_ops, &props);
> + if (IS_ERR(pchip->bsub))
> + return -EIO;
> + break;
> + default:
> + BUG();
> + }
> + return 0;
> +}
> +
> +static const struct regmap_config lm3509_regmap = {
> + .reg_bits = 8,
> + .val_bits = 8,
> + .max_register = REG_MAX,
> +};
> +
> +static int lm3509_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct lm3509_chip *pchip;
> + int ret;
> +
> + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
> + dev_err(&client->dev, "fail : i2c functionality check\n");
> + return -EOPNOTSUPP;
> + }
> +
> + pchip = devm_kzalloc(&client->dev, sizeof(struct lm3509_chip),
> + GFP_KERNEL);
> + if (!pchip)
> + return -ENOMEM;
> + pchip->dev = &client->dev;
> +
> + pchip->regmap = devm_regmap_init_i2c(client, &lm3509_regmap);
> + if (IS_ERR(pchip->regmap)) {
> + dev_err(&client->dev, "fail : allocate register map\n");
> + ret = PTR_ERR(pchip->regmap);
> + return ret;
> + }
> + i2c_set_clientdata(client, pchip);
> +
> + ret = lm3509_backlight_register(pchip, BLED_BMAIN);
> + if (ret < 0)
> + return ret;
> +
> + ret = lm3509_backlight_register(pchip, BLED_BSUB);
> + if (ret < 0)
> + return ret;
> +
> + ret = device_create_file(&(pchip->bmain->dev), &dev_attr_main_enable);
> + if (ret < 0)
> + return ret;
> +
> + ret = device_create_file(&(pchip->bmain->dev), &dev_attr_oled_enable);
> + if (ret < 0)
> + goto err_oled_enable;
> +
> + ret = device_create_file(&(pchip->bmain->dev), &dev_attr_rate);
> + if (ret < 0)
> + goto err_rate;
> +
> + ret = device_create_file(&(pchip->bsub->dev), &dev_attr_sub_enable);
> + if (ret < 0)
> + goto err_sub_enable;
> +
> + ret = device_create_file(&(pchip->bsub->dev), &dev_attr_uni_mode);
> + if (ret < 0)
> + goto err_uni_mode;
> +
> + return 0;
> +
> +err_uni_mode:
> + device_remove_file(&(pchip->bsub->dev), &dev_attr_sub_enable);
> +err_sub_enable:
> + device_remove_file(&(pchip->bmain->dev), &dev_attr_rate);
> +err_rate:
> + device_remove_file(&(pchip->bmain->dev), &dev_attr_oled_enable);
> +err_oled_enable:
> + device_remove_file(&(pchip->bmain->dev), &dev_attr_main_enable);
> + dev_err(pchip->dev, "failed : add sysfs entries\n");
> +
> + return ret;
> +}
> +
> +static int lm3509_remove(struct i2c_client *client)
> +{
> + int ret;
> + struct lm3509_chip *pchip = i2c_get_clientdata(client);
> +
> + device_remove_file(&(pchip->bsub->dev), &dev_attr_uni_mode);
> + device_remove_file(&(pchip->bsub->dev), &dev_attr_sub_enable);
> + device_remove_file(&(pchip->bmain->dev), &dev_attr_rate);
> + device_remove_file(&(pchip->bmain->dev), &dev_attr_oled_enable);
> + device_remove_file(&(pchip->bmain->dev), &dev_attr_main_enable);
> +
> + ret = regmap_write(pchip->regmap, REG_GP, 0x0);
> + if (ret < 0)
> + dev_err(pchip->dev, "i2c failed to access register\n");
> +
> + return 0;
> +}
> +
> +static const struct i2c_device_id lm3509_id[] = {
> + {LM3509_NAME, 0},
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, lm3509_id);
> +
> +static struct i2c_driver lm3509_i2c_driver = {
> + .driver = {
> + .name = LM3509_NAME,
> + },
> + .probe = lm3509_probe,
> + .remove = lm3509_remove,
> + .id_table = lm3509_id,
> +};
> +
> +module_i2c_driver(lm3509_i2c_driver);
> +
> +MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3509");
> +MODULE_AUTHOR("Daniel Jeong <gshark.jeong@xxxxxxxxx>");
> +MODULE_LICENSE("GPL v2");
> --
> 1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Next message: Johannes Thumshirn: "[PATCH v2] tty: serial: men_z135_uart: Fix driver for changes in hardware"
Previous message: Andreas Werner: "[PATCH] MAINTAINERS: Adds Andreas Werner to maintainers list for MEN F21BMC"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]