scsi: ufs: core: Add ufshcd_dme_rmw() to modify DME attributes

Introduce ufshcd_dme_rmw() API to read, modify, and write DME attributes
in UFS host controllers using a mask and value.

Signed-off-by: Nitin Rawat <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Bart Van Assche <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Nitin Rawat

drivers/ufs/core/ufshcd.c

@@ -4253,6 +4253,30 @@ int ufshcd_dme_get_attr(struct ufs_hba *hba, u32 attr_sel,
 }
 EXPORT_SYMBOL_GPL(ufshcd_dme_get_attr);
 
+/**
+ * ufshcd_dme_rmw - get modify set a DME attribute
+ * @hba: per adapter instance
+ * @mask: indicates which bits to clear from the value that has been read
+ * @val: actual value to write
+ * @attr: dme attribute
+ */
+int ufshcd_dme_rmw(struct ufs_hba *hba, u32 mask,
+		   u32 val, u32 attr)
+{
+	u32 cfg = 0;
+	int err;
+
+	err = ufshcd_dme_get(hba, UIC_ARG_MIB(attr), &cfg);
+	if (err)
+		return err;
+
+	cfg &= ~mask;
+	cfg |= (val & mask);
+
+	return ufshcd_dme_set(hba, UIC_ARG_MIB(attr), cfg);
+}
+EXPORT_SYMBOL_GPL(ufshcd_dme_rmw);
+
 /**
  * ufshcd_uic_pwr_ctrl - executes UIC commands (which affects the link power
  * state) and waits for it to take effect.

include/ufs/ufshcd.h

@@ -1480,6 +1480,7 @@ void ufshcd_resume_complete(struct device *dev);
 bool ufshcd_is_hba_active(struct ufs_hba *hba);
 void ufshcd_pm_qos_init(struct ufs_hba *hba);
 void ufshcd_pm_qos_exit(struct ufs_hba *hba);
+int ufshcd_dme_rmw(struct ufs_hba *hba, u32 mask, u32 val, u32 attr);
 
 /* Wrapper functions for safely calling variant operations */
 static inline int ufshcd_vops_init(struct ufs_hba *hba)