diff options
author | Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com> | 2011-03-22 16:30:16 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-22 17:43:59 -0700 |
commit | b1e6b7068f026e88257c20522555c78122e5a14d (patch) | |
tree | 21cbe63961ce77a0077a638fcfbda84d4530a63e /drivers/leds | |
parent | 551ea73838c5eba18d673bd4e7fb0fec77cdcb8a (diff) | |
download | linux-3.10-b1e6b7068f026e88257c20522555c78122e5a14d.tar.gz linux-3.10-b1e6b7068f026e88257c20522555c78122e5a14d.tar.bz2 linux-3.10-b1e6b7068f026e88257c20522555c78122e5a14d.zip |
leds: add driver for LM3530 ALS
Simple backlight driver for National Semiconductor LM3530. Presently only
manual mode is supported, PWM and ALS support to be added.
Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/leds')
-rw-r--r-- | drivers/leds/Kconfig | 10 | ||||
-rw-r--r-- | drivers/leds/Makefile | 1 | ||||
-rw-r--r-- | drivers/leds/leds-lm3530.c | 378 |
3 files changed, 389 insertions, 0 deletions
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 6f190f4cdbc..9bec8699b8a 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -34,6 +34,16 @@ config LEDS_ATMEL_PWM This option enables support for LEDs driven using outputs of the dedicated PWM controller found on newer Atmel SOCs. +config LEDS_LM3530 + tristate "LCD Backlight driver for LM3530" + depends on LEDS_CLASS + depends on I2C + help + This option enables support for the LCD backlight using + LM3530 ambient light sensor chip. This ALS chip can be + controlled manually or using PWM input or using ambient + light automatically. + config LEDS_LOCOMO tristate "LED Support for Locomo device" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index aae6989ff6b..39c80fca84d 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_LEDS_88PM860X) += leds-88pm860x.o obj-$(CONFIG_LEDS_ATMEL_PWM) += leds-atmel-pwm.o obj-$(CONFIG_LEDS_BD2802) += leds-bd2802.o obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o +obj-$(CONFIG_LEDS_LM3530) += leds-lm3530.o obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o obj-$(CONFIG_LEDS_S3C24XX) += leds-s3c24xx.o obj-$(CONFIG_LEDS_AMS_DELTA) += leds-ams-delta.o diff --git a/drivers/leds/leds-lm3530.c b/drivers/leds/leds-lm3530.c new file mode 100644 index 00000000000..e7089a1f6cb --- /dev/null +++ b/drivers/leds/leds-lm3530.c @@ -0,0 +1,378 @@ +/* + * Copyright (C) 2011 ST-Ericsson SA. + * Copyright (C) 2009 Motorola, Inc. + * + * License Terms: GNU General Public License v2 + * + * Simple driver for National Semiconductor LM3530 Backlight driver chip + * + * Author: Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com> + * based on leds-lm3530.c by Dan Murphy <D.Murphy@motorola.com> + */ + +#include <linux/i2c.h> +#include <linux/leds.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/input.h> +#include <linux/led-lm3530.h> +#include <linux/types.h> + +#define LM3530_LED_DEV "lcd-backlight" +#define LM3530_NAME "lm3530-led" + +#define LM3530_GEN_CONFIG 0x10 +#define LM3530_ALS_CONFIG 0x20 +#define LM3530_BRT_RAMP_RATE 0x30 +#define LM3530_ALS_ZONE_REG 0x40 +#define LM3530_ALS_IMP_SELECT 0x41 +#define LM3530_BRT_CTRL_REG 0xA0 +#define LM3530_ALS_ZB0_REG 0x60 +#define LM3530_ALS_ZB1_REG 0x61 +#define LM3530_ALS_ZB2_REG 0x62 +#define LM3530_ALS_ZB3_REG 0x63 +#define LM3530_ALS_Z0T_REG 0x70 +#define LM3530_ALS_Z1T_REG 0x71 +#define LM3530_ALS_Z2T_REG 0x72 +#define LM3530_ALS_Z3T_REG 0x73 +#define LM3530_ALS_Z4T_REG 0x74 +#define LM3530_REG_MAX 15 + +/* General Control Register */ +#define LM3530_EN_I2C_SHIFT (0) +#define LM3530_RAMP_LAW_SHIFT (1) +#define LM3530_MAX_CURR_SHIFT (2) +#define LM3530_EN_PWM_SHIFT (5) +#define LM3530_PWM_POL_SHIFT (6) +#define LM3530_EN_PWM_SIMPLE_SHIFT (7) + +#define LM3530_ENABLE_I2C (1 << LM3530_EN_I2C_SHIFT) +#define LM3530_ENABLE_PWM (1 << LM3530_EN_PWM_SHIFT) +#define LM3530_POL_LOW (1 << LM3530_PWM_POL_SHIFT) +#define LM3530_ENABLE_PWM_SIMPLE (1 << LM3530_EN_PWM_SIMPLE_SHIFT) + +/* ALS Config Register Options */ +#define LM3530_ALS_AVG_TIME_SHIFT (0) +#define LM3530_EN_ALS_SHIFT (3) +#define LM3530_ALS_SEL_SHIFT (5) + +#define LM3530_ENABLE_ALS (3 << LM3530_EN_ALS_SHIFT) + +/* Brightness Ramp Rate Register */ +#define LM3530_BRT_RAMP_FALL_SHIFT (0) +#define LM3530_BRT_RAMP_RISE_SHIFT (3) + +/* ALS Resistor Select */ +#define LM3530_ALS1_IMP_SHIFT (0) +#define LM3530_ALS2_IMP_SHIFT (4) + +/* Zone Boundary Register defaults */ +#define LM3530_DEF_ZB_0 (0x33) +#define LM3530_DEF_ZB_1 (0x66) +#define LM3530_DEF_ZB_2 (0x99) +#define LM3530_DEF_ZB_3 (0xCC) + +/* Zone Target Register defaults */ +#define LM3530_DEF_ZT_0 (0x19) +#define LM3530_DEF_ZT_1 (0x33) +#define LM3530_DEF_ZT_2 (0x4C) +#define LM3530_DEF_ZT_3 (0x66) +#define LM3530_DEF_ZT_4 (0x7F) + +struct lm3530_mode_map { + const char *mode; + enum lm3530_mode mode_val; +}; + +static struct lm3530_mode_map mode_map[] = { + { "man", LM3530_BL_MODE_MANUAL }, + { "als", LM3530_BL_MODE_ALS }, + { "pwm", LM3530_BL_MODE_PWM }, +}; + +/** + * struct lm3530_data + * @led_dev: led class device + * @client: i2c client + * @pdata: LM3530 platform data + * @mode: mode of operation - manual, ALS, PWM + */ +struct lm3530_data { + struct led_classdev led_dev; + struct i2c_client *client; + struct lm3530_platform_data *pdata; + enum lm3530_mode mode; +}; + +static const u8 lm3530_reg[LM3530_REG_MAX] = { + LM3530_GEN_CONFIG, + LM3530_ALS_CONFIG, + LM3530_BRT_RAMP_RATE, + LM3530_ALS_ZONE_REG, + LM3530_ALS_IMP_SELECT, + LM3530_BRT_CTRL_REG, + LM3530_ALS_ZB0_REG, + LM3530_ALS_ZB1_REG, + LM3530_ALS_ZB2_REG, + LM3530_ALS_ZB3_REG, + LM3530_ALS_Z0T_REG, + LM3530_ALS_Z1T_REG, + LM3530_ALS_Z2T_REG, + LM3530_ALS_Z3T_REG, + LM3530_ALS_Z4T_REG, +}; + +static int lm3530_get_mode_from_str(const char *str) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(mode_map); i++) + if (sysfs_streq(str, mode_map[i].mode)) + return mode_map[i].mode_val; + + return -1; +} + +static int lm3530_init_registers(struct lm3530_data *drvdata) +{ + int ret = 0; + int i; + u8 gen_config; + u8 als_config = 0; + u8 brt_ramp; + u8 als_imp_sel = 0; + u8 brightness; + u8 reg_val[LM3530_REG_MAX]; + struct lm3530_platform_data *pltfm = drvdata->pdata; + struct i2c_client *client = drvdata->client; + + gen_config = (pltfm->brt_ramp_law << LM3530_RAMP_LAW_SHIFT) | + ((pltfm->max_current & 7) << LM3530_MAX_CURR_SHIFT); + + if (drvdata->mode == LM3530_BL_MODE_MANUAL || + drvdata->mode == LM3530_BL_MODE_ALS) + gen_config |= (LM3530_ENABLE_I2C); + + if (drvdata->mode == LM3530_BL_MODE_ALS) { + als_config = + (pltfm->als_avrg_time << LM3530_ALS_AVG_TIME_SHIFT) | + (LM3530_ENABLE_ALS) | + (pltfm->als_input_mode << LM3530_ALS_SEL_SHIFT); + + als_imp_sel = + (pltfm->als1_resistor_sel << LM3530_ALS1_IMP_SHIFT) | + (pltfm->als2_resistor_sel << LM3530_ALS2_IMP_SHIFT); + } + + if (drvdata->mode == LM3530_BL_MODE_PWM) + gen_config |= (LM3530_ENABLE_PWM) | + (pltfm->pwm_pol_hi << LM3530_PWM_POL_SHIFT) | + (LM3530_ENABLE_PWM_SIMPLE); + + brt_ramp = (pltfm->brt_ramp_fall << LM3530_BRT_RAMP_FALL_SHIFT) | + (pltfm->brt_ramp_rise << LM3530_BRT_RAMP_RISE_SHIFT); + + brightness = pltfm->brt_val; + + reg_val[0] = gen_config; /* LM3530_GEN_CONFIG */ + reg_val[1] = als_config; /* LM3530_ALS_CONFIG */ + reg_val[2] = brt_ramp; /* LM3530_BRT_RAMP_RATE */ + reg_val[3] = 0x00; /* LM3530_ALS_ZONE_REG */ + reg_val[4] = als_imp_sel; /* LM3530_ALS_IMP_SELECT */ + reg_val[5] = brightness; /* LM3530_BRT_CTRL_REG */ + reg_val[6] = LM3530_DEF_ZB_0; /* LM3530_ALS_ZB0_REG */ + reg_val[7] = LM3530_DEF_ZB_1; /* LM3530_ALS_ZB1_REG */ + reg_val[8] = LM3530_DEF_ZB_2; /* LM3530_ALS_ZB2_REG */ + reg_val[9] = LM3530_DEF_ZB_3; /* LM3530_ALS_ZB3_REG */ + reg_val[10] = LM3530_DEF_ZT_0; /* LM3530_ALS_Z0T_REG */ + reg_val[11] = LM3530_DEF_ZT_1; /* LM3530_ALS_Z1T_REG */ + reg_val[12] = LM3530_DEF_ZT_2; /* LM3530_ALS_Z2T_REG */ + reg_val[13] = LM3530_DEF_ZT_3; /* LM3530_ALS_Z3T_REG */ + reg_val[14] = LM3530_DEF_ZT_4; /* LM3530_ALS_Z4T_REG */ + + for (i = 0; i < LM3530_REG_MAX; i++) { + ret = i2c_smbus_write_byte_data(client, + lm3530_reg[i], reg_val[i]); + if (ret) + break; + } + + return ret; +} + +static void lm3530_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brt_val) +{ + int err; + struct lm3530_data *drvdata = + container_of(led_cdev, struct lm3530_data, led_dev); + + switch (drvdata->mode) { + case LM3530_BL_MODE_MANUAL: + + /* set the brightness in brightness control register*/ + err = i2c_smbus_write_byte_data(drvdata->client, + LM3530_BRT_CTRL_REG, brt_val / 2); + if (err) + dev_err(&drvdata->client->dev, + "Unable to set brightness: %d\n", err); + break; + case LM3530_BL_MODE_ALS: + break; + case LM3530_BL_MODE_PWM: + break; + default: + break; + } +} + + +static ssize_t lm3530_mode_set(struct device *dev, struct device_attribute + *attr, const char *buf, size_t size) +{ + int err; + struct i2c_client *client = container_of( + dev->parent, struct i2c_client, dev); + struct lm3530_data *drvdata = i2c_get_clientdata(client); + int mode; + + mode = lm3530_get_mode_from_str(buf); + if (mode < 0) { + dev_err(dev, "Invalid mode\n"); + return -EINVAL; + } + + if (mode == LM3530_BL_MODE_MANUAL) + drvdata->mode = LM3530_BL_MODE_MANUAL; + else if (mode == LM3530_BL_MODE_ALS) + drvdata->mode = LM3530_BL_MODE_ALS; + else if (mode == LM3530_BL_MODE_PWM) { + dev_err(dev, "PWM mode not supported\n"); + return -EINVAL; + } + + err = lm3530_init_registers(drvdata); + if (err) { + dev_err(dev, "Setting %s Mode failed :%d\n", buf, err); + return err; + } + + return sizeof(drvdata->mode); +} + +static DEVICE_ATTR(mode, 0644, NULL, lm3530_mode_set); + +static int __devinit lm3530_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct lm3530_platform_data *pdata = client->dev.platform_data; + struct lm3530_data *drvdata; + int err = 0; + + if (pdata == NULL) { + dev_err(&client->dev, "platform data required\n"); + err = -ENODEV; + goto err_out; + } + + /* BL mode */ + if (pdata->mode > LM3530_BL_MODE_PWM) { + dev_err(&client->dev, "Illegal Mode request\n"); + err = -EINVAL; + goto err_out; + } + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "I2C_FUNC_I2C not supported\n"); + err = -EIO; + goto err_out; + } + + drvdata = kzalloc(sizeof(struct lm3530_data), GFP_KERNEL); + if (drvdata == NULL) { + err = -ENOMEM; + goto err_out; + } + + drvdata->mode = pdata->mode; + drvdata->client = client; + drvdata->pdata = pdata; + drvdata->led_dev.name = LM3530_LED_DEV; + drvdata->led_dev.brightness_set = lm3530_brightness_set; + + i2c_set_clientdata(client, drvdata); + + err = lm3530_init_registers(drvdata); + if (err < 0) { + dev_err(&client->dev, "Register Init failed: %d\n", err); + err = -ENODEV; + goto err_reg_init; + } + + err = led_classdev_register((struct device *) + &client->dev, &drvdata->led_dev); + if (err < 0) { + dev_err(&client->dev, "Register led class failed: %d\n", err); + err = -ENODEV; + goto err_class_register; + } + + err = device_create_file(drvdata->led_dev.dev, &dev_attr_mode); + if (err < 0) { + dev_err(&client->dev, "File device creation failed: %d\n", err); + err = -ENODEV; + goto err_create_file; + } + + return 0; + +err_create_file: + led_classdev_unregister(&drvdata->led_dev); +err_class_register: +err_reg_init: + kfree(drvdata); +err_out: + return err; +} + +static int __devexit lm3530_remove(struct i2c_client *client) +{ + struct lm3530_data *drvdata = i2c_get_clientdata(client); + + device_remove_file(drvdata->led_dev.dev, &dev_attr_mode); + led_classdev_unregister(&drvdata->led_dev); + kfree(drvdata); + return 0; +} + +static const struct i2c_device_id lm3530_id[] = { + {LM3530_NAME, 0}, + {} +}; + +static struct i2c_driver lm3530_i2c_driver = { + .probe = lm3530_probe, + .remove = lm3530_remove, + .id_table = lm3530_id, + .driver = { + .name = LM3530_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init lm3530_init(void) +{ + return i2c_add_driver(&lm3530_i2c_driver); +} + +static void __exit lm3530_exit(void) +{ + i2c_del_driver(&lm3530_i2c_driver); +} + +module_init(lm3530_init); +module_exit(lm3530_exit); + +MODULE_DESCRIPTION("Back Light driver for LM3530"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>"); |