Re: [PATCH] ufs: core: bsg: Add hibern8 enter/exit to ufshcd_send_bsg_uic_cmd

[Bean Huo <huobean@gmail.com>]

Arthur, 

At present, we lack a user-space tool to initiate eye monitor
measurements. Additionally, opening a channel for users in user land to
send MP commands seems unsafe.


Kind regards,
Bean

On Tue, 2025-03-04 at 13:46 +0200, Arthur Simchaev wrote:
> Eye monitor measurement functionality was added to the M-PHY v5
> specification. The measurement of the eye monitor signal for the UFS
> device begins when the link enters the hibernate state.
> Hence, allow user-layer applications the capability to send the
> hibern8
> enter command through the BSG framework. For completion, allow the
> sibling functionality of hibern8 exit as well.
> 
> Signed-off-by: Arthur Simchaev <arthur.simchaev@sandisk.com>
> ---
>  drivers/ufs/core/ufshcd.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index 4e1e214fc5a2..546ab557a77c 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -4366,6 +4366,16 @@ int ufshcd_send_bsg_uic_cmd(struct ufs_hba
> *hba, struct uic_command *uic_cmd)
>                 goto out;
>         }
>  
> +       if (uic_cmd->command == UIC_CMD_DME_HIBER_ENTER) {
> +               ret = ufshcd_uic_hibern8_enter(hba);
> +               goto out;
> +       }
> +
> +       if (uic_cmd->command == UIC_CMD_DME_HIBER_EXIT) {
> +               ret = ufshcd_uic_hibern8_exit(hba);
> +               goto out;
> +       }
> +
>         mutex_lock(&hba->uic_cmd_mutex);
>         ufshcd_add_delay_before_dme_cmd(hba);
>  
> --
> 2.34.1