Subject: [PATCH v1 3/4] scsi: ufs: allow customized delay for host enabling

From: Stanley Chu <[email-masked]>
Date: Thu, 5 Mar 2020 12:07:03 +0800

Currently a 1 ms delay is applied before polling CONTROLLER_ENABLE
bit. This delay may not be required or can be changed in different
controllers. Make the delay as a changeable value in struct ufs_hba to
allow it customized by vendors.

Signed-off-by: Stanley Chu <[email-masked]>
---
 drivers/scsi/ufs/ufshcd.c | 6 +++++-
 drivers/scsi/ufs/ufshcd.h | 1 +
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index ed61ecb98b2d..39cae907abd0 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4282,7 +4282,10 @@ int ufshcd_hba_enable(struct ufs_hba *hba)
 	 * instruction might be read back.
 	 * This delay can be changed based on the controller.
 	 */
-	usleep_range(1000, 1100);
+	if (hba->hba_enable_delay_us) {
+		usleep_range(hba->hba_enable_delay_us,
+			     hba->hba_enable_delay_us + 100);
+	}
 
 	/* wait for the host controller to complete initialization */
 	retry = 10;
@@ -8402,6 +8405,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 
 	hba->mmio_base = mmio_base;
 	hba->irq = irq;
+	hba->hba_enable_delay_us = 1000;
 
 	err = ufshcd_hba_init(hba);
 	if (err)
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 49ade1bfd085..baf1143d4839 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -662,6 +662,7 @@ struct ufs_hba {
 	u32 eh_flags;
 	u32 intr_mask;
 	u16 ee_ctrl_mask;
+	u16 hba_enable_delay_us;
 	bool is_powered;
 
 	/* Work Queues */
-- 
2.18.0
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