dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

leds: provide helper to register "leds-gpio" devices 

This function makes a deep copy of the platform data to allow it to live
in init memory.  For a kernel that supports several machines and so
includes the definition for several leds-gpio devices this saves quite
some memory because all but one definition can be free'd after boot.

As the function is used by arch code it must be builtin and so cannot go
into leds-gpio.c.

[akpm@linux-foundation.org: s/CONFIG_LED_REGISTER_GPIO/CONFIG_LEDS_REGISTER_GPIO/]
Signed-off-by: Uwe Kleine-König  <u.kleine-koenig@pengutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: H Hartley Sweeten <hartleys@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Uwe Kleine-König 2011-05-24 17:13:29 -07:00 committed by Linus Torvalds
parent 9b2da53f76
commit 4440673a95
5 changed files with 53 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/Makefile
View File

@ -94,7 +94,7 @@ obj-$(CONFIG_CPU_IDLE) += cpuidle/
obj-$(CONFIG_DMA_ENGINE) += dma/
obj-$(CONFIG_MMC) += mmc/
obj-$(CONFIG_MEMSTICK) += memstick/
obj-$(CONFIG_NEW_LEDS) += leds/
obj-y += leds/
obj-$(CONFIG_INFINIBAND) += infiniband/
obj-$(CONFIG_SGI_SN) += sn/
obj-y += firmware/

7
drivers/leds/Kconfig
View File

@ -14,6 +14,13 @@ config LEDS_CLASS
This option enables the led sysfs class in /sys/class/leds. You'll
need this to do anything useful with LEDs. If unsure, say N.
config LEDS_GPIO_REGISTER
bool
help
This option provides the function gpio_led_register_device.
As this function is used by arch code it must not be compiled as a
module.
if NEW_LEDS
comment "LED drivers"

1
drivers/leds/Makefile
View File

@ -21,6 +21,7 @@ obj-$(CONFIG_LEDS_COBALT_QUBE) += leds-cobalt-qube.o
obj-$(CONFIG_LEDS_COBALT_RAQ) += leds-cobalt-raq.o
obj-$(CONFIG_LEDS_SUNFIRE) += leds-sunfire.o
obj-$(CONFIG_LEDS_PCA9532) += leds-pca9532.o
obj-$(CONFIG_LEDS_GPIO_REGISTER) += leds-gpio-register.o
obj-$(CONFIG_LEDS_GPIO) += leds-gpio.o
obj-$(CONFIG_LEDS_LP3944) += leds-lp3944.o
obj-$(CONFIG_LEDS_LP5521) += leds-lp5521.o

42
drivers/leds/leds-gpio-register.c Normal file
View File

@ -0,0 +1,42 @@
/*
* Copyright (C) 2011 Pengutronix
* Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
*
* 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/err.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/leds.h>
/**
* gpio_led_register_device - register a gpio-led device
* @pdata: the platform data used for the new device
*
* Makes a copy of pdata and pdata->leds and registers a new leds-gpio device
* with the result. This allows to have pdata and pdata-leds in .init.rodata
* and so saves some bytes compared to a static struct platform_device with
* static platform data.
*
* Returns the registered device or an error pointer.
*/
struct platform_device *__init gpio_led_register_device(
int id, const struct gpio_led_platform_data *pdata)
{
struct platform_device *ret;
struct gpio_led_platform_data _pdata = *pdata;
_pdata.leds = kmemdup(pdata->leds,
pdata->num_leds * sizeof(*pdata->leds), GFP_KERNEL);
if (!_pdata.leds)
return ERR_PTR(-ENOMEM);
ret = platform_device_register_resndata(NULL, "leds-gpio", id,
NULL, 0, &_pdata, sizeof(_pdata));
if (IS_ERR(ret))
kfree(_pdata.leds);
return ret;
}

2
include/linux/leds.h
View File

@ -207,5 +207,7 @@ struct gpio_led_platform_data {
unsigned long *delay_off);
};
struct platform_device *gpio_led_register_device(
int id, const struct gpio_led_platform_data *pdata);
#endif /* __LINUX_LEDS_H_INCLUDED */