scsi: ufs: core: Add ufshcd_send_bsg_uic_cmd() for UFS BSG

User layer applications can send UIC GET/SET commands via the BSG
framework, and if the user layer application sends a UIC SET command to the
PA_PWRMODE attribute, a power mode change shall be initiated in UniPro and
two interrupts shall be triggered if the power mode is successfully
changed, i.e., UIC Command Completion interrupt and UIC Power Mode
interrupt.

The current UFS BSG code calls ufshcd_send_uic_cmd() directly, with which
the second interrupt, i.e., UIC Power Mode interrupt, shall be treated as
unhandled interrupt. In addition, after the UIC command is completed, user
layer application has to poll UniPro and/or M-PHY state machine to confirm
the power mode change is finished.

Add a new wrapper function ufshcd_send_bsg_uic_cmd() and call it from
ufs_bsg_request() so that if a UIC SET command is targeting the PA_PWRMODE
attribute it can be redirected to ufshcd_uic_pwr_ctrl().

Fixes: e77044c ("scsi: ufs-bsg: Add support for uic commands in ufs_bsg_request()")
Co-developed-by: Can Guo <[email protected]>
Signed-off-by: Can Guo <[email protected]>
Signed-off-by: Ziqi Chen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Bean Huo <[email protected]>
Reviewed-by: Avri Altman <[email protected]>
Reviewed-by: Peter Wang <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: quic-ziqichen

drivers/ufs/core/ufs_bsg.c

@@ -170,7 +170,7 @@ static int ufs_bsg_request(struct bsg_job *job)
 		break;
 	case UPIU_TRANSACTION_UIC_CMD:
 		memcpy(&uc, &bsg_request->upiu_req.uc, UIC_CMD_SIZE);
-		ret = ufshcd_send_uic_cmd(hba, &uc);
+		ret = ufshcd_send_bsg_uic_cmd(hba, &uc);
 		if (ret)
 			dev_err(hba->dev, "send uic cmd: error code %d\n", ret);
 

drivers/ufs/core/ufshcd-priv.h

@@ -84,6 +84,7 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, u8 desc_index,
 			    u8 **buf, bool ascii);
 
 int ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd);
+int ufshcd_send_bsg_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd);
 
 int ufshcd_exec_raw_upiu_cmd(struct ufs_hba *hba,
 			     struct utp_upiu_req *req_upiu,

drivers/ufs/core/ufshcd.c

@@ -4319,6 +4319,42 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd)
 	return ret;
 }
 
+/**
+ * ufshcd_send_bsg_uic_cmd - Send UIC commands requested via BSG layer and retrieve the result
+ * @hba: per adapter instance
+ * @uic_cmd: UIC command
+ *
+ * Return: 0 only if success.
+ */
+int ufshcd_send_bsg_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd)
+{
+	int ret;
+
+	if (hba->quirks & UFSHCD_QUIRK_BROKEN_UIC_CMD)
+		return 0;
+
+	ufshcd_hold(hba);
+
+	if (uic_cmd->argument1 == UIC_ARG_MIB(PA_PWRMODE) &&
+	    uic_cmd->command == UIC_CMD_DME_SET) {
+		ret = ufshcd_uic_pwr_ctrl(hba, uic_cmd);
+		goto out;
+	}
+
+	mutex_lock(&hba->uic_cmd_mutex);
+	ufshcd_add_delay_before_dme_cmd(hba);
+
+	ret = __ufshcd_send_uic_cmd(hba, uic_cmd);
+	if (!ret)
+		ret = ufshcd_wait_for_uic_cmd(hba, uic_cmd);
+
+	mutex_unlock(&hba->uic_cmd_mutex);
+
+out:
+	ufshcd_release(hba);
+	return ret;
+}
+
 /**
  * ufshcd_uic_change_pwr_mode - Perform the UIC power mode chage
  *				using DME_SET primitives.