Re: [PATCH v4 1/3] powerpc/powernv: Add OPAL interfaces for accessing and modifying system LED states

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Tue, 2015-04-28 at 15:39 +0530, Vasant Hegde wrote:
> From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
> 
> This patch registers the following two new OPAL interfaces calls
> for the platform LED subsystem. With the help of these new OPAL calls,
> the kernel will be able to get or set the state of various individual
> LEDs on the system at any given location code which is passed through
> the LED specific device tree nodes.
> 
> 	(1) OPAL_LEDS_GET_INDICATOR     opal_leds_get_ind
> 	(2) OPAL_LEDS_SET_INDICATOR     opal_leds_set_ind
> 
> Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
> Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
> Acked-by: Stewart Smith <stewart@linux.vnet.ibm.com>
> Tested-by: Stewart Smith <stewart@linux.vnet.ibm.com>

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

> ---
> Changes in v4:
>   - Updated macros to reflect platform.
> 
>  arch/powerpc/include/asm/opal-api.h            |   29 +++++++++++++++++++++++-
>  arch/powerpc/include/asm/opal.h                |    5 ++++
>  arch/powerpc/platforms/powernv/opal-wrappers.S |    2 ++
>  3 files changed, 35 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h
> index 0321a90..ff85397 100644
> --- a/arch/powerpc/include/asm/opal-api.h
> +++ b/arch/powerpc/include/asm/opal-api.h
> @@ -153,7 +153,9 @@
>  #define OPAL_FLASH_READ				110
>  #define OPAL_FLASH_WRITE			111
>  #define OPAL_FLASH_ERASE			112
> -#define OPAL_LAST				112
> +#define OPAL_LEDS_GET_INDICATOR			114
> +#define OPAL_LEDS_SET_INDICATOR			115
> +#define OPAL_LAST				115
>  
>  /* Device tree flags */
>  
> @@ -730,6 +732,31 @@ struct opal_i2c_request {
>  	__be64 buffer_ra;		/* Buffer real address */
>  };
>  
> +/* LED Mode */
> +#define POWERNV_LED_MODE_LIGHT_PATH	"lightpath"
> +#define POWERNV_LED_MODE_GUIDING_LIGHT	"guidinglight"
> +
> +/* LED type */
> +#define POWERNV_LED_TYPE_IDENTIFY	"identify"
> +#define POWERNV_LED_TYPE_FAULT		"fault"
> +#define POWERNV_LED_TYPE_ATTENTION	"attention"
> +
> +/* LED location */
> +#define POWERNV_LED_LOC_ENCLOSURE	"enclosure"
> +#define POWERNV_LED_LOC_DESCENDENT	"descendent"
> +
> +enum OpalSlotLedType {
> +	OPAL_SLOT_LED_TYPE_ID = 0,	/* IDENTIFY LED */
> +	OPAL_SLOT_LED_TYPE_FAULT = 1,	/* FAULT LED */
> +	OPAL_SLOT_LED_TYPE_ATTN = 2,	/* System Attention LED */
> +	OPAL_SLOT_LED_TYPE_MAX = 3
> +};
> +
> +enum OpalSlotLedState {
> +	OPAL_SLOT_LED_STATE_OFF = 0,	/* LED is OFF */
> +	OPAL_SLOT_LED_STATE_ON = 1	/* LED is ON */
> +};
> +
>  #endif /* __ASSEMBLY__ */
>  
>  #endif /* __OPAL_API_H */
> diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
> index 042af1a..e06dc7e 100644
> --- a/arch/powerpc/include/asm/opal.h
> +++ b/arch/powerpc/include/asm/opal.h
> @@ -193,6 +193,11 @@ int64_t opal_ipmi_recv(uint64_t interface, struct opal_ipmi_msg *msg,
>  		uint64_t *msg_len);
>  int64_t opal_i2c_request(uint64_t async_token, uint32_t bus_id,
>  			 struct opal_i2c_request *oreq);
> +int64_t opal_leds_get_ind(char *loc_code, u64 *led_mask,
> +			  u64 *led_value, u64 *max_led_type);
> +int64_t opal_leds_set_ind(uint64_t token, char *loc_code, const u64 led_mask,
> +			  const u64 led_value, u64 *max_led_type);
> +
>  
>  int64_t opal_flash_read(uint64_t id, uint64_t offset, uint64_t buf,
>  		uint64_t size, uint64_t token);
> diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S
> index 4e74037..20d4da4 100644
> --- a/arch/powerpc/platforms/powernv/opal-wrappers.S
> +++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
> @@ -295,3 +295,5 @@ OPAL_CALL(opal_i2c_request,			OPAL_I2C_REQUEST);
>  OPAL_CALL(opal_flash_read,			OPAL_FLASH_READ);
>  OPAL_CALL(opal_flash_write,			OPAL_FLASH_WRITE);
>  OPAL_CALL(opal_flash_erase,			OPAL_FLASH_ERASE);
> +OPAL_CALL(opal_leds_get_ind,			OPAL_LEDS_GET_INDICATOR);
> +OPAL_CALL(opal_leds_set_ind,			OPAL_LEDS_SET_INDICATOR);