Re: [PATCH] acpi : create sun sysfs file in container device

[Toshi Kani <toshi.kani@hp.com>]

Yasuaki Ishimatsu wrote:
> There is no comment on the patch about a month. But I want to merge the patch
> into linux-3.6. So I resend it. 
> 
> ---
> Even if container device has _SUN method, the method is ignored. So we cannot
> know slot-unique ID number of the container device. The patch creates "sun"
> file in sysfs so that we can recognize it.
> 
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

Hi Yasuaki,

The patch works fine on my setup.  However, it may be better to
implement this feature in acpi_device_setup_files(), so that we can
generally support it for any ACPI objects with _SUN.  We might also be
able to put sun value into acpi_device_pnp since it is a static value.
This way, we don't have to call _SUN at every sysfs access, and it could
be useful for debugging as well.

Thanks,
-Toshi

> ---
>  drivers/acpi/container.c |   36 +++++++++++++++++++++++++++++++++---
>  1 file changed, 33 insertions(+), 3 deletions(-)
> 
> Index: linux-3.5-rc1/drivers/acpi/container.c
> ===================================================================
> --- linux-3.5-rc1.orig/drivers/acpi/container.c	2012-06-14 15:35:31.045500166 +0900
> +++ linux-3.5-rc1/drivers/acpi/container.c	2012-06-14 16:40:13.010405144 +0900
> @@ -32,6 +32,7 @@
>  #include <linux/slab.h>
>  #include <linux/types.h>
>  #include <linux/acpi.h>
> +#include <linux/device.h>
>  #include <acpi/acpi_bus.h>
>  #include <acpi/acpi_drivers.h>
>  #include <acpi/container.h>
> @@ -93,10 +94,30 @@ static int is_device_present(acpi_handle
>  }
> 
>  /*******************************************************************/
> +
> +static ssize_t acpi_device_sun_show(struct device *dev,
> +				    struct device_attribute *attr, char *buf) {
> +	struct acpi_device *device = to_acpi_device(dev);
> +	acpi_status status;
> +	unsigned long long sun;
> +
> +	status = acpi_evaluate_integer(device->handle, "_SUN", NULL,  &sun);
> +	if (ACPI_FAILURE(status))
> +		return 0;
> +
> +	return sprintf(buf, "%llu\n", sun);
> +}
> +
> +static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
> +
> +/*******************************************************************/
> +
>  static int acpi_container_add(struct acpi_device *device)
>  {
>  	struct acpi_container *container;
> -
> +	acpi_status status;
> +	acpi_handle temp;
> +	int result = 0;
> 
>  	if (!device) {
>  		printk(KERN_ERR PREFIX "device is NULL\n");
> @@ -115,13 +136,22 @@ static int acpi_container_add(struct acp
>  	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device <%s> bid <%s>\n",
>  			  acpi_device_name(device), acpi_device_bid(device)));
> 
> -	return 0;
> +	status = acpi_get_handle(device->handle, "_SUN", &temp);
> +	if (ACPI_SUCCESS(status))
> +		result = device_create_file(&device->dev, &dev_attr_sun);
> +
> +	return result;
>  }
> 
>  static int acpi_container_remove(struct acpi_device *device, int type)
>  {
> -	acpi_status status = AE_OK;
> +	acpi_status status;
>  	struct acpi_container *pc = NULL;
> +	acpi_handle temp;
> +
> +	status = acpi_get_handle(device->handle, "_SUN", &temp);
> +	if (ACPI_SUCCESS(status))
> +		device_remove_file(&device->dev, &dev_attr_sun);
> 
>  	pc = acpi_driver_data(device);
>  	kfree(pc);
>