linux-kernel - Re: [PATCH 1/3] firmware: arm_scpi: add support for device power state management

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1465304305.2833.13.camel@linaro.org>
Date:	Tue, 07 Jun 2016 13:58:25 +0100
From:	"Jon Medhurst (Tixy)" <tixy@...aro.org>
To:	Sudeep Holla <sudeep.holla@....com>
Cc:	linux-kernel@...r.kernel.org,
	Mathieu Poirier <mathieu.poirier@...aro.org>,
	Suzuki K Poulose <suzuki.poulose@....com>,
	linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 1/3] firmware: arm_scpi: add support for device power
 state management

On Mon, 2016-06-06 at 16:53 +0100, Sudeep Holla wrote:
> SCPI protocol supports device power state management. This deals with
> power states of various peripheral devices in the system other than the
> core compute subsystem.
> 
> This patch adds support for the power state management of those
> peripheral devices.
> 
> Cc: linux-arm-kernel@...ts.infradead.org
> Signed-off-by: Sudeep Holla <sudeep.holla@....com>
> ---
>  drivers/firmware/arm_scpi.c   | 29 +++++++++++++++++++++++++++++
>  include/linux/scpi_protocol.h |  2 ++
>  2 files changed, 31 insertions(+)
> 
> diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
> index 51c6db0774cc..ca6afd2217a8 100644
> --- a/drivers/firmware/arm_scpi.c
> +++ b/drivers/firmware/arm_scpi.c
> @@ -231,6 +231,11 @@ struct sensor_value {
>  	__le32 hi_val;
>  } __packed;
> 
> +struct dev_pstate_set {
> +	u16 dev_id;
> +	u8 pstate;
> +} __packed;
> +
>  static struct scpi_drvinfo *scpi_info;
> 
>  static int scpi_linux_errmap[SCPI_ERR_MAX] = {
> @@ -537,6 +542,28 @@ static int scpi_sensor_get_value(u16 sensor, u64 *val)
>  	return ret;
>  }
> 
> +static int scpi_device_get_power_state(u16 dev_id)
> +{
> +	int ret;
> +	u8 pstate;
> +
> +	ret = scpi_send_message(SCPI_CMD_GET_DEVICE_PWR_STATE, &dev_id,
> +				sizeof(dev_id), &pstate, sizeof(pstate));

Don't you need to run translate dev_id to little-endian before sending
it? You remembered to do that next function...

> +	return ret ? ret : pstate;
> +}
> +
> +static int scpi_device_set_power_state(u16 dev_id, u8 pstate)
> +{
> +	int stat;
> +	struct dev_pstate_set dev_set = {
> +		.dev_id = cpu_to_le16(dev_id),
> +		.pstate = pstate,
> +	};
> +
> +	return scpi_send_message(SCPI_CMD_SET_DEVICE_PWR_STATE, &dev_set,
> +				 sizeof(dev_set), &stat, sizeof(stat));
> +}
> +

[...]

-- 
Tixy