ufs: improve init sequence

In ->hce_enable_notify() callback the vendor specific initialization
may carry out additional DME configuration using UIC commands and
hence the UIC command completion interrupt enable bit should be set
before the post reset notification.
Add retries if the link-startup fails. This is required since due to
hardware timing issues, the Uni-Pro link-startup might fail. The UFS
HCI recovery procedure contradicts the Uni-Pro sequence. The UFS HCI
specifies to resend DME_LINKSTARTUP command after IS.ULLS (link-lost
interrupt) is received. The Uni-Pro specifies that if link-startup
fails the link is in "down" state. The link-lost is indicated to the
DME user only when the link is up. Hence, the UFS HCI recovery procedure
of waiting for IS.ULLS and retrying link-startup may not work properly.

At the end, if detection fails, power off (disable clocks, regulators,
phy) if the UFS device detection fails. This saves power while UFS device
is not embedded into the system.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index bc0f7ed02605..eddb3f3b4139 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -228,6 +228,7 @@ struct ufs_hba_variant_ops {
  * @eh_flags: Error handling flags
  * @intr_mask: Interrupt Mask Bits
  * @ee_ctrl_mask: Exception event control mask
+ * @is_powered: flag to check if HBA is powered
  * @eh_work: Worker to handle UFS errors that require s/w attention
  * @eeh_work: Worker to handle exception events
  * @errors: HBA errors
@@ -283,6 +284,7 @@ struct ufs_hba {
 	u32 eh_flags;
 	u32 intr_mask;
 	u16 ee_ctrl_mask;
+	bool is_powered;
 
 	/* Work Queues */
 	struct work_struct eh_work;