Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753639AbYLRMvY (ORCPT ); Thu, 18 Dec 2008 07:51:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751887AbYLRMvA (ORCPT ); Thu, 18 Dec 2008 07:51:00 -0500 Received: from mail.gmx.net ([213.165.64.20]:56280 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753827AbYLRMu7 (ORCPT ); Thu, 18 Dec 2008 07:50:59 -0500 X-Authenticated: #20450766 X-Provags-ID: V01U2FsdGVkX18/GxpXz7w/xxtcIpRbUR9cvqWPoAZ9iT7UqlXVOB 01hEggq0DzOWOd Date: Thu, 18 Dec 2008 13:51:06 +0100 (CET) From: Guennadi Liakhovetski X-X-Sender: lyakh@axis700.grange To: Ben Dooks cc: linux-kernel@vger.kernel.org, rpurdie@rpsys.net Subject: [PATCH v2] leds: add a dac124s085 SPI LED driver In-Reply-To: <20081218120619.GJ12431@fluff.org.uk> Message-ID: References: <20081218120619.GJ12431@fluff.org.uk> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Y-GMX-Trusted: 0 X-FuHaFi: 0.41 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A simple LED driver using the DAC124S085 DAC from NatSemi Signed-off-by: Guennadi Liakhovetski --- Changes since v1: implemented corrections by Ben Dooks: macro instead of a magic constant, endianness conversion, ARRAY_SIZE instead of a hard-coded constant. Still needs a previous patch making maximum brightness configurable: http://marc.info/?l=linux-kernel&m=122771446123369&w=2 drivers/leds/Kconfig | 7 ++ drivers/leds/Makefile | 3 + drivers/leds/leds-dac124s085.c | 147 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 157 insertions(+), 0 deletions(-) create mode 100644 drivers/leds/leds-dac124s085.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index a4a1ae2..a28635f 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -178,6 +178,13 @@ 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 bc247cb..8780152 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -26,6 +26,9 @@ obj-$(CONFIG_LEDS_DA903X) += leds-da903x.o obj-$(CONFIG_LEDS_HP_DISK) += leds-hp-disk.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..9bd25c1 --- /dev/null +++ b/drivers/leds/leds-dac124s085.c @@ -0,0 +1,147 @@ +/* + * Copyright 2008 + * Guennadi Liakhovetski, DENX Software Engineering, + * + * 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 +#include +#include +#include +#include + +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 "); +MODULE_DESCRIPTION("DAC124S085 LED driver"); +MODULE_LICENSE("GPL v2"); -- 1.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/