[PATCH v3 0/1] leds: Add driver for PC Engines APU/APU2 LEDs

[PATCH v3 0/1] leds: Add driver for PC Engines APU/APU2 LEDs

[Alan Mizrahi]

Hello,

This patch adds support for the PC Engines APU/APU2 front panel LEDs.

Changes from v1 to v2:
- use LED_ON enum constant
- readability improvements

Alan Mizrahi (1):
  leds: Add driver for PC Engines APU/APU2 LEDs

 drivers/leds/Kconfig    |  10 ++
 drivers/leds/Makefile   |   1 +
 drivers/leds/leds-apu.c | 278 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 289 insertions(+)
 create mode 100644 drivers/leds/leds-apu.c

-- 
2.9.0

[PATCH v3 1/1] leds: Add driver for PC Engines APU/APU2 LEDs

[Alan Mizrahi]

---
 drivers/leds/Kconfig    |  10 ++
 drivers/leds/Makefile   |   1 +
 drivers/leds/leds-apu.c | 278 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 289 insertions(+)
 create mode 100644 drivers/leds/leds-apu.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 52ea34e..318a28f 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -57,6 +57,16 @@ config LEDS_AAT1290
 	depends on PINCTRL
 	help
 	 This option enables support for the LEDs on the AAT1290.
+config LEDS_APU
+	tristate "Front panel LED support for PC Engines APU/APU2 boards"
+	depends on LEDS_CLASS
+	depends on X86 && DMI
+	help
+	  This driver makes the PC Engines APU/APU2 front panel LEDs
+	  accessible from userspace programs through the LED subsystem.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called leds-apu.
 
 config LEDS_AS3645A
 	tristate "AS3645A LED flash controller support"
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 7d7b265..6de4979 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_LEDS_TRIGGERS)		+= led-triggers.o
 # LED Platform Drivers
 obj-$(CONFIG_LEDS_88PM860X)		+= leds-88pm860x.o
 obj-$(CONFIG_LEDS_AAT1290)		+= leds-aat1290.o
+obj-$(CONFIG_LEDS_APU)			+= leds-apu.o
 obj-$(CONFIG_LEDS_AS3645A)		+= leds-as3645a.o
 obj-$(CONFIG_LEDS_BCM6328)		+= leds-bcm6328.o
 obj-$(CONFIG_LEDS_BCM6358)		+= leds-bcm6358.o
diff --git a/drivers/leds/leds-apu.c b/drivers/leds/leds-apu.c
new file mode 100644
index 0000000..3a4f1e1
--- /dev/null
+++ b/drivers/leds/leds-apu.c
@@ -0,0 +1,278 @@
+/*
+ * drivers/leds/leds-apu.c
+ * Copyright (C) 2017 Alan Mizrahi, alan at mizrahi dot com dot ve
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/dmi.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#define APU1_FCH_ACPI_MMIO_BASE 0xFED80000
+#define APU1_FCH_GPIO_BASE      (APU1_FCH_ACPI_MMIO_BASE + 0x01BD)
+#define APU1_LEDON              0x08
+#define APU1_LEDOFF             0xC8
+#define APU1_NUM_GPIO           3
+#define APU1_IOSIZE             sizeof(u8)
+
+#define APU2_FCH_ACPI_MMIO_BASE 0xFED80000
+#define APU2_FCH_GPIO_BASE      (APU2_FCH_ACPI_MMIO_BASE + 0x1500)
+#define APU2_GPIO_BIT_WRITE     22
+#define APU2_APU2_NUM_GPIO      4
+#define APU2_IOSIZE             sizeof(u32)
+
+/* LED access parameters */
+struct apu_param {
+	void __iomem *addr; /* for ioread/iowrite */
+};
+
+/* LED private data */
+struct apu_led_priv {
+	struct led_classdev cdev;
+	struct apu_param param;
+};
+#define cdev_to_priv(c) container_of(c, struct apu_led_priv, cdev)
+
+/* LED profile */
+struct apu_led_profile {
+	const char *name;
+	enum led_brightness brightness;
+	unsigned long offset; /* for devm_ioremap */
+};
+
+/* Supported platform types */
+enum apu_led_platform_types {
+	APU1_LED_PLATFORM,
+	APU2_LED_PLATFORM,
+};
+
+struct apu_led_pdata {
+	struct platform_device *pdev;
+	struct apu_led_priv *pled;
+	struct apu_led_profile *profile;
+	enum apu_led_platform_types platform;
+	int num_led_instances;
+	int iosize; /* for devm_ioremap() */
+	spinlock_t lock;
+};
+
+static struct apu_led_pdata *apu_led;
+
+static struct apu_led_profile apu1_led_profile[] = {
+	{ "apu:green:1", LED_ON,  APU1_FCH_GPIO_BASE + 0 * APU1_IOSIZE },
+	{ "apu:green:2", LED_OFF, APU1_FCH_GPIO_BASE + 1 * APU1_IOSIZE },
+	{ "apu:green:3", LED_OFF, APU1_FCH_GPIO_BASE + 2 * APU1_IOSIZE },
+};
+
+static struct apu_led_profile apu2_led_profile[] = {
+	{ "apu2:green:1", LED_ON,  APU2_FCH_GPIO_BASE + 68 * APU2_IOSIZE },
+	{ "apu2:green:2", LED_OFF, APU2_FCH_GPIO_BASE + 69 * APU2_IOSIZE },
+	{ "apu2:green:3", LED_OFF, APU2_FCH_GPIO_BASE + 70 * APU2_IOSIZE },
+};
+
+static struct dmi_system_id apu_led_dmi_table[] __initdata = {
+	{
+		.ident = "apu",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "PC Engines"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "APU")
+		}
+	},
+	{
+		.ident = "apu2",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "PC Engines"),
+			DMI_MATCH(DMI_BOARD_NAME, "APU2")
+		}
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(dmi, apu_led_dmi_table);
+
+static void apu1_led_brightness_set(struct led_classdev *led, enum led_brightness value)
+{
+	struct apu_led_priv *pled = cdev_to_priv(led);
+
+	spin_lock(&apu_led->lock);
+	iowrite8(value ? APU1_LEDON : APU1_LEDOFF, pled->param.addr);
+	spin_unlock(&apu_led->lock);
+}
+
+static void apu2_led_brightness_set(struct led_classdev *led, enum led_brightness value)
+{
+	struct apu_led_priv *pled = cdev_to_priv(led);
+	u32 value_new;
+
+	spin_lock(&apu_led->lock);
+
+	value_new = ioread32(pled->param.addr);
+
+	if (value)
+		value_new &= ~BIT(APU2_GPIO_BIT_WRITE);
+	else
+		value_new |= BIT(APU2_GPIO_BIT_WRITE);
+
+	iowrite32(value_new, pled->param.addr);
+
+	spin_unlock(&apu_led->lock);
+}
+
+static int apu_led_config(struct device *dev, struct apu_led_pdata *apuld)
+{
+	int i;
+	int err;
+
+	apu_led->pled = devm_kzalloc(dev,
+		sizeof(struct apu_led_priv) * apu_led->num_led_instances,
+		GFP_KERNEL);
+
+	if (!apu_led->pled)
+		return -ENOMEM;
+
+	for (i = 0; i < apu_led->num_led_instances; i++) {
+		struct apu_led_priv *pled = &apu_led->pled[i];
+		struct led_classdev *led_cdev = &pled->cdev;
+
+		led_cdev->name = apu_led->profile[i].name;
+		led_cdev->brightness = apu_led->profile[i].brightness;
+		led_cdev->max_brightness = 1;
+		led_cdev->flags = LED_CORE_SUSPENDRESUME;
+		if (apu_led->platform == APU1_LED_PLATFORM)
+			led_cdev->brightness_set = apu1_led_brightness_set;
+		else if (apu_led->platform == APU2_LED_PLATFORM)
+			led_cdev->brightness_set = apu2_led_brightness_set;
+
+		pled->param.addr = devm_ioremap(dev,
+				apu_led->profile[i].offset, apu_led->iosize);
+		if (!pled->param.addr) {
+			err = -ENOMEM;
+			goto error;
+		}
+
+		err = led_classdev_register(dev, led_cdev);
+		if (err)
+			goto error;
+
+		led_cdev->brightness_set(led_cdev, apu_led->profile[i].brightness);
+	}
+
+	return 0;
+
+error:
+	while (i-- > 0)
+		led_classdev_unregister(&apu_led->pled[i].cdev);
+
+	return err;
+}
+
+static int __init apu_led_probe(struct platform_device *pdev)
+{
+	apu_led = devm_kzalloc(&pdev->dev, sizeof(*apu_led), GFP_KERNEL);
+
+	if (!apu_led)
+		return -ENOMEM;
+
+	apu_led->pdev = pdev;
+
+	if (dmi_match(DMI_BOARD_NAME, "APU")) {
+		apu_led->profile = apu1_led_profile;
+		apu_led->platform = APU1_LED_PLATFORM;
+		apu_led->num_led_instances = ARRAY_SIZE(apu1_led_profile);
+		apu_led->iosize = APU1_IOSIZE;
+	} else if (dmi_match(DMI_BOARD_NAME, "APU2")) {
+		apu_led->profile = apu2_led_profile;
+		apu_led->platform = APU2_LED_PLATFORM;
+		apu_led->num_led_instances = ARRAY_SIZE(apu2_led_profile);
+		apu_led->iosize = APU2_IOSIZE;
+	}
+
+	spin_lock_init(&apu_led->lock);
+	return apu_led_config(&pdev->dev, apu_led);
+}
+
+static struct platform_driver apu_led_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+	},
+};
+
+static int __init apu_led_init(void)
+{
+	struct platform_device *pdev;
+	int err;
+
+	if (!dmi_match(DMI_SYS_VENDOR, "PC Engines")) {
+		pr_err("No PC Engines board detected\n");
+		return -ENODEV;
+	}
+	if (!(dmi_match(DMI_PRODUCT_NAME, "APU") || dmi_match(DMI_PRODUCT_NAME, "APU2"))) {
+		pr_err("Unknown PC Engines board: %s\n",
+				dmi_get_system_info(DMI_PRODUCT_NAME));
+		return -ENODEV;
+	}
+
+	pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
+	if (IS_ERR(pdev)) {
+		pr_err("Device allocation failed\n");
+		return PTR_ERR(pdev);
+	}
+
+	err = platform_driver_probe(&apu_led_driver, apu_led_probe);
+	if (err) {
+		pr_err("Probe platform driver failed\n");
+		platform_device_unregister(pdev);
+	}
+
+	return err;
+}
+
+static void __exit apu_led_exit(void)
+{
+	int i;
+
+	for (i = 0; i < apu_led->num_led_instances; i++)
+		led_classdev_unregister(&apu_led->pled[i].cdev);
+
+	platform_device_unregister(apu_led->pdev);
+	platform_driver_unregister(&apu_led_driver);
+}
+
+module_init(apu_led_init);
+module_exit(apu_led_exit);
+
+MODULE_AUTHOR("Alan Mizrahi");
+MODULE_DESCRIPTION("PC Engines APU family LED driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:leds_apu");
-- 
2.9.0

Re: [PATCH v3 1/1] leds: Add driver for PC Engines APU/APU2 LEDs

[Jacek Anaszewski]

Hi Alan,

Thanks for the update.

I've found a few more minor issues:

- the patch is missing commit message and Signed-off-by tag
- for the remaining ones please refer to the code below

On 11/02/2017 02:19 AM, Alan Mizrahi wrote:
> ---
>  drivers/leds/Kconfig    |  10 ++
>  drivers/leds/Makefile   |   1 +
>  drivers/leds/leds-apu.c | 278 ++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 289 insertions(+)
>  create mode 100644 drivers/leds/leds-apu.c
> 
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 52ea34e..318a28f 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -57,6 +57,16 @@ config LEDS_AAT1290
>  	depends on PINCTRL
>  	help
>  	 This option enables support for the LEDs on the AAT1290.
> +config LEDS_APU
> +	tristate "Front panel LED support for PC Engines APU/APU2 boards"
> +	depends on LEDS_CLASS
> +	depends on X86 && DMI
> +	help
> +	  This driver makes the PC Engines APU/APU2 front panel LEDs
> +	  accessible from userspace programs through the LED subsystem.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called leds-apu.
>  
>  config LEDS_AS3645A
>  	tristate "AS3645A LED flash controller support"
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index 7d7b265..6de4979 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_LEDS_TRIGGERS)		+= led-triggers.o
>  # LED Platform Drivers
>  obj-$(CONFIG_LEDS_88PM860X)		+= leds-88pm860x.o
>  obj-$(CONFIG_LEDS_AAT1290)		+= leds-aat1290.o
> +obj-$(CONFIG_LEDS_APU)			+= leds-apu.o
>  obj-$(CONFIG_LEDS_AS3645A)		+= leds-as3645a.o
>  obj-$(CONFIG_LEDS_BCM6328)		+= leds-bcm6328.o
>  obj-$(CONFIG_LEDS_BCM6358)		+= leds-bcm6358.o
> diff --git a/drivers/leds/leds-apu.c b/drivers/leds/leds-apu.c
> new file mode 100644
> index 0000000..3a4f1e1
> --- /dev/null
> +++ b/drivers/leds/leds-apu.c
> @@ -0,0 +1,278 @@
> +/*
> + * drivers/leds/leds-apu.c
> + * Copyright (C) 2017 Alan Mizrahi, alan at mizrahi dot com dot ve
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions are met:
> + *
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice, this list of conditions and the following disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + * 3. Neither the names of the copyright holders nor the names of its
> + *    contributors may be used to endorse or promote products derived from
> + *    this software without specific prior written permission.
> + *
> + * Alternatively, this software may be distributed under the terms of the
> + * GNU General Public License ("GPL") version 2 as published by the Free
> + * Software Foundation.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
> + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
> + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
> + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
> + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
> + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
> + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
> + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
> + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
> + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
> + * POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +#include <linux/dmi.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/leds.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#define APU1_FCH_ACPI_MMIO_BASE 0xFED80000
> +#define APU1_FCH_GPIO_BASE      (APU1_FCH_ACPI_MMIO_BASE + 0x01BD)
> +#define APU1_LEDON              0x08
> +#define APU1_LEDOFF             0xC8
> +#define APU1_NUM_GPIO           3
> +#define APU1_IOSIZE             sizeof(u8)
> +
> +#define APU2_FCH_ACPI_MMIO_BASE 0xFED80000
> +#define APU2_FCH_GPIO_BASE      (APU2_FCH_ACPI_MMIO_BASE + 0x1500)
> +#define APU2_GPIO_BIT_WRITE     22
> +#define APU2_APU2_NUM_GPIO      4
> +#define APU2_IOSIZE             sizeof(u32)
> +
> +/* LED access parameters */
> +struct apu_param {
> +	void __iomem *addr; /* for ioread/iowrite */
> +};
> +
> +/* LED private data */
> +struct apu_led_priv {
> +	struct led_classdev cdev;
> +	struct apu_param param;
> +};
> +#define cdev_to_priv(c) container_of(c, struct apu_led_priv, cdev)
> +
> +/* LED profile */
> +struct apu_led_profile {
> +	const char *name;
> +	enum led_brightness brightness;
> +	unsigned long offset; /* for devm_ioremap */
> +};
> +
> +/* Supported platform types */
> +enum apu_led_platform_types {
> +	APU1_LED_PLATFORM,
> +	APU2_LED_PLATFORM,
> +};
> +
> +struct apu_led_pdata {
> +	struct platform_device *pdev;
> +	struct apu_led_priv *pled;
> +	struct apu_led_profile *profile;

s/struct/const struct/

> +	enum apu_led_platform_types platform;
> +	int num_led_instances;
> +	int iosize; /* for devm_ioremap() */
> +	spinlock_t lock;
> +};
> +
> +static struct apu_led_pdata *apu_led;
> +
> +static struct apu_led_profile apu1_led_profile[] = {
> +	{ "apu:green:1", LED_ON,  APU1_FCH_GPIO_BASE + 0 * APU1_IOSIZE },
> +	{ "apu:green:2", LED_OFF, APU1_FCH_GPIO_BASE + 1 * APU1_IOSIZE },
> +	{ "apu:green:3", LED_OFF, APU1_FCH_GPIO_BASE + 2 * APU1_IOSIZE },
> +};

s/static struct/static const struct/

> +static struct apu_led_profile apu2_led_profile[] = {
> +	{ "apu2:green:1", LED_ON,  APU2_FCH_GPIO_BASE + 68 * APU2_IOSIZE },
> +	{ "apu2:green:2", LED_OFF, APU2_FCH_GPIO_BASE + 69 * APU2_IOSIZE },
> +	{ "apu2:green:3", LED_OFF, APU2_FCH_GPIO_BASE + 70 * APU2_IOSIZE },
> +};

s/static struct/static const struct/

> +static struct dmi_system_id apu_led_dmi_table[] __initdata = {
> +	{
> +		.ident = "apu",
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "PC Engines"),
> +			DMI_MATCH(DMI_PRODUCT_NAME, "APU")
> +		}
> +	},
> +	{
> +		.ident = "apu2",
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "PC Engines"),
> +			DMI_MATCH(DMI_BOARD_NAME, "APU2")
> +		}
> +	},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(dmi, apu_led_dmi_table);

When the driver is compiled into kernel we're getting a warning here:

drivers/leds/leds-apu.c:105:29: warning: ‘apu_led_dmi_table’ defined but
not used [-Wunused-variable]
 static struct dmi_system_id apu_led_dmi_table[] __initdata = {

In order to get rid of it please change this line to:

static const struct dmi_system_id apu_led_dmi_table[] __initconst = {


> +
> +static void apu1_led_brightness_set(struct led_classdev *led, enum led_brightness value)
> +{
> +	struct apu_led_priv *pled = cdev_to_priv(led);
> +
> +	spin_lock(&apu_led->lock);
> +	iowrite8(value ? APU1_LEDON : APU1_LEDOFF, pled->param.addr);
> +	spin_unlock(&apu_led->lock);
> +}
> +
> +static void apu2_led_brightness_set(struct led_classdev *led, enum led_brightness value)
> +{
> +	struct apu_led_priv *pled = cdev_to_priv(led);
> +	u32 value_new;
> +
> +	spin_lock(&apu_led->lock);
> +
> +	value_new = ioread32(pled->param.addr);
> +
> +	if (value)
> +		value_new &= ~BIT(APU2_GPIO_BIT_WRITE);
> +	else
> +		value_new |= BIT(APU2_GPIO_BIT_WRITE);
> +
> +	iowrite32(value_new, pled->param.addr);
> +
> +	spin_unlock(&apu_led->lock);
> +}
> +
> +static int apu_led_config(struct device *dev, struct apu_led_pdata *apuld)
> +{
> +	int i;
> +	int err;
> +
> +	apu_led->pled = devm_kzalloc(dev,
> +		sizeof(struct apu_led_priv) * apu_led->num_led_instances,
> +		GFP_KERNEL);
> +
> +	if (!apu_led->pled)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < apu_led->num_led_instances; i++) {
> +		struct apu_led_priv *pled = &apu_led->pled[i];
> +		struct led_classdev *led_cdev = &pled->cdev;
> +
> +		led_cdev->name = apu_led->profile[i].name;
> +		led_cdev->brightness = apu_led->profile[i].brightness;
> +		led_cdev->max_brightness = 1;
> +		led_cdev->flags = LED_CORE_SUSPENDRESUME;
> +		if (apu_led->platform == APU1_LED_PLATFORM)
> +			led_cdev->brightness_set = apu1_led_brightness_set;
> +		else if (apu_led->platform == APU2_LED_PLATFORM)
> +			led_cdev->brightness_set = apu2_led_brightness_set;
> +
> +		pled->param.addr = devm_ioremap(dev,
> +				apu_led->profile[i].offset, apu_led->iosize);
> +		if (!pled->param.addr) {
> +			err = -ENOMEM;
> +			goto error;
> +		}
> +
> +		err = led_classdev_register(dev, led_cdev);
> +		if (err)
> +			goto error;
> +
> +		led_cdev->brightness_set(led_cdev, apu_led->profile[i].brightness);
> +	}
> +
> +	return 0;
> +
> +error:
> +	while (i-- > 0)
> +		led_classdev_unregister(&apu_led->pled[i].cdev);
> +
> +	return err;
> +}
> +
> +static int __init apu_led_probe(struct platform_device *pdev)
> +{
> +	apu_led = devm_kzalloc(&pdev->dev, sizeof(*apu_led), GFP_KERNEL);
> +
> +	if (!apu_led)
> +		return -ENOMEM;
> +
> +	apu_led->pdev = pdev;
> +
> +	if (dmi_match(DMI_BOARD_NAME, "APU")) {
> +		apu_led->profile = apu1_led_profile;
> +		apu_led->platform = APU1_LED_PLATFORM;
> +		apu_led->num_led_instances = ARRAY_SIZE(apu1_led_profile);
> +		apu_led->iosize = APU1_IOSIZE;
> +	} else if (dmi_match(DMI_BOARD_NAME, "APU2")) {
> +		apu_led->profile = apu2_led_profile;
> +		apu_led->platform = APU2_LED_PLATFORM;
> +		apu_led->num_led_instances = ARRAY_SIZE(apu2_led_profile);
> +		apu_led->iosize = APU2_IOSIZE;
> +	}
> +
> +	spin_lock_init(&apu_led->lock);
> +	return apu_led_config(&pdev->dev, apu_led);
> +}
> +
> +static struct platform_driver apu_led_driver = {
> +	.driver = {
> +		.name = KBUILD_MODNAME,
> +	},
> +};
> +
> +static int __init apu_led_init(void)
> +{
> +	struct platform_device *pdev;
> +	int err;
> +
> +	if (!dmi_match(DMI_SYS_VENDOR, "PC Engines")) {
> +		pr_err("No PC Engines board detected\n");
> +		return -ENODEV;
> +	}
> +	if (!(dmi_match(DMI_PRODUCT_NAME, "APU") || dmi_match(DMI_PRODUCT_NAME, "APU2"))) {
> +		pr_err("Unknown PC Engines board: %s\n",
> +				dmi_get_system_info(DMI_PRODUCT_NAME));
> +		return -ENODEV;
> +	}
> +
> +	pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
> +	if (IS_ERR(pdev)) {
> +		pr_err("Device allocation failed\n");
> +		return PTR_ERR(pdev);
> +	}
> +
> +	err = platform_driver_probe(&apu_led_driver, apu_led_probe);
> +	if (err) {
> +		pr_err("Probe platform driver failed\n");
> +		platform_device_unregister(pdev);
> +	}
> +
> +	return err;
> +}
> +
> +static void __exit apu_led_exit(void)
> +{
> +	int i;
> +
> +	for (i = 0; i < apu_led->num_led_instances; i++)
> +		led_classdev_unregister(&apu_led->pled[i].cdev);
> +
> +	platform_device_unregister(apu_led->pdev);
> +	platform_driver_unregister(&apu_led_driver);
> +}
> +
> +module_init(apu_led_init);
> +module_exit(apu_led_exit);
> +
> +MODULE_AUTHOR("Alan Mizrahi");
> +MODULE_DESCRIPTION("PC Engines APU family LED driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:leds_apu");
> 

-- 
Best regards,
Jacek Anaszewski