On Fri, Dec 11, 2020 at 03:00:30PM +0100, Bean Huo wrote:
> From: Bean Huo <beanhuo@xxxxxxxxxx>
>
> Currently UFS WriteBooster driver uses clock scaling up/down to set
> WB on/off, for the platform which doesn't support UFSHCD_CAP_CLK_SCALING,
> WB will be always on. Provide a sysfs attribute to enable/disable WB
> during runtime. Write 1/0 to "wb_on" sysfs node to enable/disable UFS WB.
>
> Reviewed-by: Avri Altman <avri.altman@xxxxxxx>
> Reviewed-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
> Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
> ---
> drivers/scsi/ufs/ufs-sysfs.c | 41 ++++++++++++++++++++++++++++++++++++
> drivers/scsi/ufs/ufshcd.c | 3 +--
> drivers/scsi/ufs/ufshcd.h | 2 ++
> 3 files changed, 44 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
> index 08e72b7eef6a..2b4e9fe935cc 100644
> --- a/drivers/scsi/ufs/ufs-sysfs.c
> +++ b/drivers/scsi/ufs/ufs-sysfs.c
> @@ -189,6 +189,45 @@ static ssize_t auto_hibern8_store(struct device *dev,
> return count;
> }
>
> +static ssize_t wb_on_show(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> + return scnprintf(buf, PAGE_SIZE, "%d\n", hba->wb_enabled);
Please just use sysfs_emit().
> +}
> +
> +static ssize_t wb_on_store(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct ufs_hba *hba = dev_get_drvdata(dev);
> + unsigned int wb_enable;
> + ssize_t res;
> +
> + if (ufshcd_is_clkscaling_supported(hba)) {
> + /*
> + * If the platform supports UFSHCD_CAP_AUTO_BKOPS_SUSPEND,
> + * turn WB on/off will be done while clock scaling up/down.
> + */
> + dev_warn(dev, "To control WB through wb_on is not allowed!\n");
> + return -EOPNOTSUPP;
> + }
> + if (!ufshcd_is_wb_allowed(hba))
> + return -EOPNOTSUPP;
> +
> + if (kstrtouint(buf, 0, &wb_enable))
> + return -EINVAL;
> +
> + if (wb_enable != 0 && wb_enable != 1)
> + return -EINVAL;
> +
> + pm_runtime_get_sync(hba->dev);
> + res = ufshcd_wb_ctrl(hba, wb_enable);
> + pm_runtime_put_sync(hba->dev);
> +
> + return res < 0 ? res : count;
> +}
Where is the new Documentation/ABI/ update for this new sysfs file you
are adding?
thanks,
greg k-h
