diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/leds/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/leds/Makefile | 3 | ||||
| -rw-r--r-- | drivers/leds/leds-dac124s085.c | 150 |
3 files changed, 160 insertions, 0 deletions
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 90d39e5..16a9408 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -190,6 +190,13 @@ config LEDS_DA903X This option enables support for on-chip LED drivers found on Dialog Semiconductor DA9030/DA9034 PMICs. +config LEDS_DAC124S085 + tristate "LED Support for DAC124S085 SPI DAC" + depends on LEDS_CLASS && SPI + help + This option enables support for DAC124S085 SPI DAC from NatSemi, + which can be used to control up to four LEDs. + comment "LED Triggers" config LEDS_TRIGGERS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 9d76f0f..4157e86 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -25,6 +25,9 @@ obj-$(CONFIG_LEDS_PCA955X) += leds-pca955x.o obj-$(CONFIG_LEDS_DA903X) += leds-da903x.o obj-$(CONFIG_LEDS_WM8350) += leds-wm8350.o +# LED SPI Drivers +obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o + # LED Triggers obj-$(CONFIG_LEDS_TRIGGER_TIMER) += ledtrig-timer.o obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK) += ledtrig-ide-disk.o diff --git a/drivers/leds/leds-dac124s085.c b/drivers/leds/leds-dac124s085.c new file mode 100644 index 0000000..098d9aa --- /dev/null +++ b/drivers/leds/leds-dac124s085.c @@ -0,0 +1,150 @@ +/* + * Copyright 2008 + * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de> + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License. See the file COPYING in the main + * directory of this archive for more details. + * + * LED driver for the DAC124S085 SPI DAC + */ + +#include <linux/gfp.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/workqueue.h> +#include <linux/spi/spi.h> + +struct dac124s085_led { + struct led_classdev ldev; + struct spi_device *spi; + int id; + int brightness; + char name[sizeof("dac124s085-3")]; + + struct mutex mutex; + struct work_struct work; + spinlock_t lock; +}; + +struct dac124s085 { + struct dac124s085_led leds[4]; +}; + +#define REG_WRITE (0 << 12) +#define REG_WRITE_UPDATE (1 << 12) +#define ALL_WRITE_UPDATE (2 << 12) +#define POWER_DOWN_OUTPUT (3 << 12) + +static void dac124s085_led_work(struct work_struct *work) +{ + struct dac124s085_led *led = container_of(work, struct dac124s085_led, + work); + u16 word; + + mutex_lock(&led->mutex); + word = cpu_to_le16(((led->id) << 14) | REG_WRITE_UPDATE | + (led->brightness & 0xfff)); + spi_write(led->spi, (const u8 *)&word, sizeof(word)); + mutex_unlock(&led->mutex); +} + +static void dac124s085_set_brightness(struct led_classdev *ldev, + enum led_brightness brightness) +{ + struct dac124s085_led *led = container_of(ldev, struct dac124s085_led, + ldev); + + spin_lock(&led->lock); + led->brightness = brightness; + schedule_work(&led->work); + spin_unlock(&led->lock); +} + +static int dac124s085_probe(struct spi_device *spi) +{ + struct dac124s085 *dac; + struct dac124s085_led *led; + int i, ret; + + dac = kzalloc(sizeof(*dac), GFP_KERNEL); + if (!dac) + return -ENOMEM; + + spi->bits_per_word = 16; + + for (i = 0; i < ARRAY_SIZE(dac->leds); i++) { + led = dac->leds + i; + led->id = i; + led->brightness = LED_OFF; + led->spi = spi; + snprintf(led->name, sizeof(led->name), "dac124s085-%d", i); + spin_lock_init(&led->lock); + INIT_WORK(&led->work, dac124s085_led_work); + mutex_init(&led->mutex); + led->ldev.name = led->name; + led->ldev.brightness = LED_OFF; + led->ldev.max_brightness = 0xfff; + led->ldev.brightness_set = dac124s085_set_brightness; + ret = led_classdev_register(&spi->dev, &led->ldev); + if (ret < 0) + goto eledcr; + } + + spi_set_drvdata(spi, dac); + + return 0; + +eledcr: + while (i--) + led_classdev_unregister(&dac->leds[i].ldev); + + spi_set_drvdata(spi, NULL); + kfree(dac); + return ret; +} + +static int dac124s085_remove(struct spi_device *spi) +{ + struct dac124s085 *dac = spi_get_drvdata(spi); + int i; + + for (i = 0; i < ARRAY_SIZE(dac->leds); i++) { + led_classdev_unregister(&dac->leds[i].ldev); + cancel_work_sync(&dac->leds[i].work); + } + + spi_set_drvdata(spi, NULL); + kfree(dac); + + return 0; +} + +static struct spi_driver dac124s085_driver = { + .probe = dac124s085_probe, + .remove = dac124s085_remove, + .driver = { + .name = "dac124s085", + .owner = THIS_MODULE, + }, +}; + +static int __init dac124s085_leds_init(void) +{ + return spi_register_driver(&dac124s085_driver); +} + +static void __exit dac124s085_leds_exit(void) +{ + spi_unregister_driver(&dac124s085_driver); +} + +module_init(dac124s085_leds_init); +module_exit(dac124s085_leds_exit); + +MODULE_AUTHOR("Guennadi Liakhovetski <lg@denx.de>"); +MODULE_DESCRIPTION("DAC124S085 LED driver"); +MODULE_LICENSE("GPL v2"); |