Re: [PATCH 2.6.27-rc3] led: driver for LEDs on PCEngines ALIX.2 and ALIX.3 boards

Andrew Morton
2008-08-22T18:52:41Z

On Tue, 19 Aug 2008 22:23:41 +0500
Constantin Baranov <const@const.mimas.ru> wrote:

> From: Constantin Baranov <const@tltsu.ru>
>
> Driver for LEDs on PCEngines ALIX.2 and ALIX.3 system boards.
>
> Signed-off-by: Constantin Baranov <const@tltsu.ru>
> ---
> drivers/leds/Kconfig | 6 +
> drivers/leds/Makefile | 1
> drivers/leds/leds-alix.c | 146 +++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 153 insertions(+)
>
> diff -uprN linux-2.6.27-rc3/drivers/leds/Kconfig linux-2.6.27-rc3-alix/drivers/leds/Kconfig
> --- linux-2.6.27-rc3/drivers/leds/Kconfig 2008-08-19 20:14:06.355647765 +0500
> +++ linux-2.6.27-rc3-alix/drivers/leds/Kconfig 2008-08-19 20:20:08.023147125 +0500
> @@ -77,6 +77,12 @@ config LEDS_WRAP
> help
> This option enables support for the PCEngines WRAP programmable LEDs.
>
> +config LEDS_ALIX
> + tristate "LED support for ALIX series"
> + depends on LEDS_CLASS && X86
> + help
> + This option enables support for the PCEngines ALIX.2 and ALIX.3 LEDs.
> +
> config LEDS_H1940
> tristate "LED Support for iPAQ H1940 device"
> depends on LEDS_CLASS && ARCH_H1940
> diff -uprN linux-2.6.27-rc3/drivers/leds/leds-alix.c linux-2.6.27-rc3-alix/drivers/leds/leds-alix.c
> --- linux-2.6.27-rc3/drivers/leds/leds-alix.c 1970-01-01 04:00:00.000000000 +0400
> +++ linux-2.6.27-rc3-alix/drivers/leds/leds-alix.c 2008-08-19 21:59:05.207153570 +0500
> @@ -0,0 +1,146 @@
> +/*
> + * LEDs driver for PCEngines ALIX.2 and ALIX.3
> + *
> + * Copyright (C) 2008 Constantin Baranov <const@tltsu.ru>
> + */
> +
> +#include <asm/io.h>

Please use linux/io.h. scripts/checkpatch.pl has a nice warning for this.

> +#include <linux/err.h>
> +#include <linux/kernel.h>
> +#include <linux/leds.h>
> +#include <linux/platform_device.h>
> +
> +struct alix_led {
> + struct led_classdev cdev;
> + unsigned short port;
> + unsigned int on_value;
> + unsigned int off_value;
> +};
> +
> +static void alix_led_set(struct led_classdev *led_cdev,
> + enum led_brightness brightness)
> +{
> + struct alix_led *led_dev =
> + container_of(led_cdev, struct alix_led, cdev);
> + if (brightness)
> + outl(led_dev->on_value, led_dev->port);
> + else
> + outl(led_dev->off_value, led_dev->port);
> +}
> +
> +static struct alix_led alix_leds[] = {
> + {
> + .cdev = {
> + .name = "alix:1",
> + .brightness_set = alix_led_set,
> + },
> + .port = 0x6100,
> + .on_value = 1 << 22,
> + .off_value = 1 << 6,
> + },
> + {
> + .cdev = {
> + .name = "alix:2",
> + .brightness_set = alix_led_set,
> + },
> + .port = 0x6180,
> + .on_value = 1 << 25,
> + .off_value = 1 << 9,
> + },
> + {
> + .cdev = {
> + .name = "alix:3",
> + .brightness_set = alix_led_set,
> + },
> + .port = 0x6180,
> + .on_value = 1 << 27,
> + .off_value = 1 << 11,
> + },
> +};
> +
> +#ifdef CONFIG_PM
> +
> +static int alix_led_suspend(struct platform_device *dev, pm_message_t state)
> +{
> + int i;
> + for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
> + led_classdev_suspend(&alix_leds[i].cdev);
> + return 0;
> +}
> +
> +static int alix_led_resume(struct platform_device *dev)
> +{
> + int i;
> + for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
> + led_classdev_resume(&alix_leds[i].cdev);
> + return 0;
> +}
> +
> +#else
> +
> +#define alix_led_suspend NULL
> +#define alix_led_resume NULL
> +
> +#endif
> +
> +static int __init alix_led_probe(struct platform_device *pdev)
> +{
> + int i;
> + int ret = 0;
> +
> + for (i = 0; i < ARRAY_SIZE(alix_leds) && ret >= 0; i++)
> + ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
> +
> + if (ret < 0) {
> + for (i = i - 2; i >= 0; i--)

this is off-by-one, surely.

If we get here with i==1, we'll loop 4 billion times.

> + led_classdev_unregister(&alix_leds[i].cdev);
> + }
> +
> + return ret;
> +}
> +
> +static int alix_led_remove(struct platform_device *pdev)
> +{
> + int i;
> + for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
> + led_classdev_unregister(&alix_leds[i].cdev);
> + return 0;
> +}

A blank line between end-of-locals and start-of-code is conventional.

> +static struct platform_driver alix_led_driver = {
> + .remove = alix_led_remove,
> + .suspend = alix_led_suspend,
> + .resume = alix_led_resume,
> + .driver = {
> + .name = KBUILD_MODNAME,
> + .owner = THIS_MODULE,
> + },
> +};
> +
> +static struct platform_device *pdev;
> +
> +static int __init alix_led_init(void)
> +{
> + int ret;
> + pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
> + if (!IS_ERR(pdev)) {
> + ret = platform_driver_probe(&alix_led_driver, alix_led_probe);
> + if (ret)
> + platform_device_unregister(pdev);
> + } else
> + ret = PTR_ERR(pdev);
> + return ret;
> +}
> +
> +static void __exit alix_led_exit(void)
> +{
> + platform_device_unregister(pdev);
> + platform_driver_unregister(&alix_led_driver);
> +}
> +
> +module_init(alix_led_init);
> +module_exit(alix_led_exit);
> +
> +MODULE_AUTHOR("Constantin Baranov <const@tltsu.ru>");
> +MODULE_DESCRIPTION("PCEngines ALIX LED driver");
> +MODULE_LICENSE("GPL");
> diff -uprN linux-2.6.27-rc3/drivers/leds/Makefile linux-2.6.27-rc3-alix/drivers/leds/Makefile
> --- linux-2.6.27-rc3/drivers/leds/Makefile 2008-08-19 20:14:06.365646999 +0500
> +++ linux-2.6.27-rc3-alix/drivers/leds/Makefile 2008-08-19 20:20:22.485647344 +0500
> @@ -13,6 +13,7 @@ obj-$(CONFIG_LEDS_S3C24XX) += leds-s3c2
> obj-$(CONFIG_LEDS_AMS_DELTA) += leds-ams-delta.o
> obj-$(CONFIG_LEDS_NET48XX) += leds-net48xx.o
> obj-$(CONFIG_LEDS_WRAP) += leds-wrap.o
> +obj-$(CONFIG_LEDS_ALIX) += leds-alix.o
> obj-$(CONFIG_LEDS_H1940) += leds-h1940.o
> obj-$(CONFIG_LEDS_COBALT_QUBE) += leds-cobalt-qube.o
> obj-$(CONFIG_LEDS_COBALT_RAQ) += leds-cobalt-raq.o

How's this look?

From: Andrew Morton <akpm@linux-foundation.org>

- cleanups

- fix off-by-one on error path

Cc: Constantin Baranov <const@tltsu.ru>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

drivers/leds/leds-alix.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff -puN drivers/leds/leds-alix.c~led-driver-for-leds-on-pcengines-alix2-and-alix3-boards-fix drivers/leds/leds-alix.c
--- a/drivers/leds/leds-alix.c~led-driver-for-leds-on-pcengines-alix2-and-alix3-boards-fix
+++ a/drivers/leds/leds-alix.c
@@ -4,7 +4,7 @@
* Copyright (C) 2008 Constantin Baranov <const@tltsu.ru>
*/

-#include <asm/io.h>
+#include <linux/io.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/leds.h>
@@ -22,6 +22,7 @@ static void alix_led_set(struct led_clas
{
struct alix_led *led_dev =
container_of(led_cdev, struct alix_led, cdev);
+
if (brightness)
outl(led_dev->on_value, led_dev->port);
else
@@ -63,6 +64,7 @@ static struct alix_led alix_leds[] = {
static int alix_led_suspend(struct platform_device *dev, pm_message_t state)
{
int i;
+
for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
led_classdev_suspend(&alix_leds[i].cdev);
return 0;
@@ -71,6 +73,7 @@ static int alix_led_suspend(struct platf
static int alix_led_resume(struct platform_device *dev)
{
int i;
+
for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
led_classdev_resume(&alix_leds[i].cdev);
return 0;
@@ -92,7 +95,7 @@ static int __init alix_led_probe(struct
ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);

if (ret < 0) {
- for (i = i - 2; i >= 0; i--)
+ while (--i >= 0)
led_classdev_unregister(&alix_leds[i].cdev);
}

@@ -102,6 +105,7 @@ static int __init alix_led_probe(struct
static int alix_led_remove(struct platform_device *pdev)
{
int i;
+
for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
led_classdev_unregister(&alix_leds[i].cdev);
return 0;
@@ -122,6 +126,7 @@ static struct platform_device *pdev;
static int __init alix_led_init(void)
{
int ret;
+
pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
if (!IS_ERR(pdev)) {
ret = platform_driver_probe(&alix_led_driver, alix_led_probe);
_