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Message-ID: <8a9cc52c-9c7d-1f8f-8a98-1a816f59aa79@quicinc.com>
Date:   Thu, 14 Sep 2023 17:03:24 +0530
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Subject: Re: [PATCH 5/6] scsi: ufs: ufs-sysfs: Expose UFS power info
To:     Can Guo <quic_cang@quicinc.com>, <mani@kernel.org>,
        <quic_nguyenb@quicinc.com>, <martin.petersen@oracle.com>
CC:     <linux-scsi@vger.kernel.org>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        "Avri Altman" <avri.altman@wdc.com>,
        Bart Van Assche <bvanassche@acm.org>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        Bean Huo <beanhuo@micron.com>,
        "Arthur Simchaev" <arthur.simchaev@wdc.com>,
        Lu Hongfei <luhongfei@vivo.com>,
        "open list" <linux-kernel@vger.kernel.org>
References: <1694411968-14413-1-git-send-email-quic_cang@quicinc.com>
 <1694411968-14413-6-git-send-email-quic_cang@quicinc.com>
Content-Language: en-US
From:   Nitin Rawat <quic_nitirawa@quicinc.com>
In-Reply-To: <1694411968-14413-6-git-send-email-quic_cang@quicinc.com>
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On 9/11/2023 11:29 AM, Can Guo wrote:
> Having UFS power info available in sysfs makes it easier to tell the state
> of the link during runtime considering we have a bounch of power saving
> features and various combinations for backward compatiblity.

Please fix spelling mistake - *bounch -> bunch


> 
> Signed-off-by: Can Guo <quic_cang@quicinc.com>
> ---
>   drivers/ufs/core/ufs-sysfs.c | 71 ++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 71 insertions(+)
> 
> diff --git a/drivers/ufs/core/ufs-sysfs.c b/drivers/ufs/core/ufs-sysfs.c
> index c959064..53af490 100644
> --- a/drivers/ufs/core/ufs-sysfs.c
> +++ b/drivers/ufs/core/ufs-sysfs.c
> @@ -628,6 +628,76 @@ static const struct attribute_group ufs_sysfs_monitor_group = {
>   	.attrs = ufs_sysfs_monitor_attrs,
>   };
>   
> +static ssize_t gear_show(struct device *dev, struct device_attribute *attr,
> +			 char *buf)
> +{
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%u\n", hba->pwr_info.gear_rx);
> +}
> +
> +static ssize_t lane_show(struct device *dev, struct device_attribute *attr,
> +			 char *buf)
> +{
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%u\n", hba->pwr_info.lane_rx);
> +}
> +
> +static ssize_t mode_show(struct device *dev, struct device_attribute *attr,
> +			 char *buf)
> +{
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%u\n", hba->pwr_info.pwr_rx);
> +}
> +
> +static ssize_t rate_show(struct device *dev, struct device_attribute *attr,
> +			 char *buf)
> +{
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%u\n", hba->pwr_info.hs_rate);
> +}
> +
> +static ssize_t dev_pm_show(struct device *dev, struct device_attribute *attr,
> +			   char *buf)
> +{
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%d\n", hba->curr_dev_pwr_mode);
> +}
> +
> +static ssize_t link_state_show(struct device *dev,
> +			       struct device_attribute *attr, char *buf)
> +{
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%d\n", hba->uic_link_state);
> +}
> +
> +static DEVICE_ATTR_RO(gear);
> +static DEVICE_ATTR_RO(lane);
> +static DEVICE_ATTR_RO(mode);
> +static DEVICE_ATTR_RO(rate);
> +static DEVICE_ATTR_RO(dev_pm);
> +static DEVICE_ATTR_RO(link_state);
> +
> +static struct attribute *ufs_power_info_attrs[] = {
> +	&dev_attr_gear.attr,
> +	&dev_attr_lane.attr,
> +	&dev_attr_mode.attr,
> +	&dev_attr_rate.attr,
> +	&dev_attr_dev_pm.attr,
> +	&dev_attr_link_state.attr,
> +	NULL
> +};
> +
> +static const struct attribute_group ufs_sysfs_power_info_group = {
> +	.name = "power_info",
> +	.attrs = ufs_power_info_attrs,
> +};
> +
>   static ssize_t ufs_sysfs_read_desc_param(struct ufs_hba *hba,
>   				  enum desc_idn desc_id,
>   				  u8 desc_index,
> @@ -1233,6 +1303,7 @@ static const struct attribute_group *ufs_sysfs_groups[] = {
>   	&ufs_sysfs_default_group,
>   	&ufs_sysfs_capabilities_group,
>   	&ufs_sysfs_monitor_group,
> +	&ufs_sysfs_power_info_group,
>   	&ufs_sysfs_device_descriptor_group,
>   	&ufs_sysfs_interconnect_descriptor_group,
>   	&ufs_sysfs_geometry_descriptor_group,


How about having one power mode attribute displaying all useful info 
(lane, gear, mode, rate).

Regards,
Nitin Rawat