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

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

[Constantin Baranov]

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>
+#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--)
+			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;
+}
+
+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

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

[Andrew Morton]

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);
_

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

[Willy Tarreau]

Hi Andrew,

On Fri, Aug 22, 2008 at 11:51:50AM -0700, Andrew Morton wrote:
> On Tue, 19 Aug 2008 22:23:41 +0500
> Constantin Baranov <const@const.mimas.ru> wrote:
> > +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.

No we will not because i is signed. We'll simply not enter the loop.
However, the code looks suspicious and the reasoning behind i-2 isn't
quite clear.

Willy

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

[Constantin Baranov]

Andrew Morton wrote:
> 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);
>  	}

At the first iteration this while-loop will attempt to unregister
device that has failed and thus is not registered.
My for-loop starts from device immediately before failed one.
Note that probe routine originates from leds-ams-delta.c.

>  
> @@ -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);
> _
> 

I have fixed header and whitespaces.

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 |  151 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 158 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 +1,151 @@
+/*
+ * LEDs driver for PCEngines ALIX.2 and ALIX.3
+ *
+ * Copyright (C) 2008 Constantin Baranov <const@tltsu.ru>
+ */
+
+#include <linux/err.h>
+#include <linux/io.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--)
+			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;
+}
+
+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

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

[Andrew Morton]

On Sat, 23 Aug 2008 02:08:15 +0500
Constantin Baranov <const@const.mimas.ru> wrote:

> >  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);
> >  	}
> 
> At the first iteration this while-loop will attempt to unregister
> device that has failed and thus is not registered.
> My for-loop starts from device immediately before failed one.

ug, OK, the complex expression in that for-loop is to blame.

For maintinability we should aim for code which is as simple and as
straightfroward as possible and which adheres to oft-used and
well-understood kernel idioms.

For example, this?

static int __init alix_led_probe(struct platform_device *pdev)
{
	int i;
	int ret;

	for (i = 0; i < ARRAY_SIZE(alix_leds); i++) {
		ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
		if (ret < 0)
			goto fail;
	}
	return 0;

fail:
	while (--i >= 0)
		led_classdev_unregister(&alix_leds[i].cdev);
	return ret;
}

(note there's no longer a need for a fake initalisation of `ret')

> Note that probe routine originates from leds-ams-delta.c.

That's what you get for copying stuff :(

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

[Constantin Baranov]

Andrew Morton wrote:
> On Sat, 23 Aug 2008 02:08:15 +0500
> Constantin Baranov <const@const.mimas.ru> wrote:
> 
>>>  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);
>>>  	}
>> At the first iteration this while-loop will attempt to unregister
>> device that has failed and thus is not registered.
>> My for-loop starts from device immediately before failed one.
> 
> ug, OK, the complex expression in that for-loop is to blame.
> 
> For maintinability we should aim for code which is as simple and as
> straightfroward as possible and which adheres to oft-used and
> well-understood kernel idioms.
> 
> For example, this?
> 
> static int __init alix_led_probe(struct platform_device *pdev)
> {
> 	int i;
> 	int ret;
> 
> 	for (i = 0; i < ARRAY_SIZE(alix_leds); i++) {
> 		ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
> 		if (ret < 0)
> 			goto fail;
> 	}
> 	return 0;
> 
> fail:
> 	while (--i >= 0)
> 		led_classdev_unregister(&alix_leds[i].cdev);
> 	return ret;
> }
> 
> (note there's no longer a need for a fake initalisation of `ret')
> 
>> Note that probe routine originates from leds-ams-delta.c.
> 
> That's what you get for copying stuff :(

Well, this variant looks better and correct and still works.
Should I post again patch or fix-patch?

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

[Andrew Morton]

On Sat, 23 Aug 2008 22:11:56 +0500 Constantin Baranov <const@const.mimas.ru> wrote:

> > For example, this?
> > 
> > static int __init alix_led_probe(struct platform_device *pdev)
> > {
> > 	int i;
> > 	int ret;
> > 
> > 	for (i = 0; i < ARRAY_SIZE(alix_leds); i++) {
> > 		ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
> > 		if (ret < 0)
> > 			goto fail;
> > 	}
> > 	return 0;
> > 
> > fail:
> > 	while (--i >= 0)
> > 		led_classdev_unregister(&alix_leds[i].cdev);
> > 	return ret;
> > }
> > 
> > (note there's no longer a need for a fake initalisation of `ret')
> > 
> >> Note that probe routine originates from leds-ams-delta.c.
> > 
> > That's what you get for copying stuff :(
> 
> Well, this variant looks better and correct and still works.
> Should I post again patch or fix-patch?

I already queued that as an incremental:

--- 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;
@@ -86,22 +89,25 @@ static int alix_led_resume(struct platfo
 static int __init alix_led_probe(struct platform_device *pdev)
 {
 	int i;
-	int ret = 0;
+	int ret;
 
-	for (i = 0; i < ARRAY_SIZE(alix_leds) && ret >= 0; i++)
+	for (i = 0; i < ARRAY_SIZE(alix_leds); i++) {
 		ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
-
-	if (ret < 0) {
-		for (i = i - 2; i >= 0; i--)
-			led_classdev_unregister(&alix_leds[i].cdev);
+		if (ret < 0)
+			goto fail;
 	}
+	return 0;
 
+fail:
+	while (--i >= 0)
+		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;
@@ -122,6 +128,7 @@ 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);
_

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

[Stefan Richter]

Andrew Morton wrote:
> On Tue, 19 Aug 2008 22:23:41 +0500
> Constantin Baranov <const@const.mimas.ru> wrote:
>> --- 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
...
>> +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;
>> +}
...
> How's this look?
...
> @@ -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);
>  	}


Really?  Constantin's code looks correct to me.  He increments i once 
more after failure.

Perhaps write it easier to read; i.e. in the same way as most error 
return checks everywhere in the kernel:

	for (i = 0; i < ARRAY_SIZE(alix_leds); i++) {
		ret = led_classdev_register(...etc...);
		if (ret < 0)
			break;
	}

	if (ret < 0)
		while (i--)
			led_classdev_unregister(&alix_leds[i].cdev);


Or		while (--i >= 0)

or		for (i--; i >= 0; i--)
-- 
Stefan Richter
-=====-==--- =--- ==---
http://arcgraph.de/sr/

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

[Stefan Richter]

Stefan Richter wrote:
[...something that has already been resolved.  Need to remember to check 
inbox.lkml before replying to an almost 2 days old post.]
-- 
Stefan Richter
-=====-==--- =--- ==---
http://arcgraph.de/sr/