[PATCH v5 1/2] scsi: ufs: Fix ufs clk specs violation

From: Ziqi Chen <ziqichen@codeaurora.org>
To: asutoshd@codeaurora.org, nguyenb@codeaurora.org,
	cang@codeaurora.org, hongwus@codeaurora.org,
	rnayak@codeaurora.org, vinholikatti@gmail.com,
	jejb@linux.vnet.ibm.com, martin.petersen@oracle.com,
	linux-scsi@vger.kernel.org, kernel-team@android.com,
	saravanak@google.com, salyzyn@google.com,
	ziqichen@codeaurora.org, kwmad.kim@samsung.com,
	stanley.chu@mediatek.com
Cc: Alim Akhtar <alim.akhtar@samsung.com>,
	Avri Altman <avri.altman@wdc.com>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	Bean Huo <beanhuo@micron.com>,
	linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v5 1/2] scsi: ufs: Fix ufs clk specs violation
Date: Fri,  8 Jan 2021 15:28:03 +0800	[thread overview]
Message-ID: <1610090885-50099-2-git-send-email-ziqichen@codeaurora.org> (raw)
In-Reply-To: <1610090885-50099-1-git-send-email-ziqichen@codeaurora.org>

As per specs, e.g, JESD220E chapter 7.2, while powering
off/on the ufs device, REF_CLK signal should be between
VSS(Ground) and VCCQ/VCCQ2.

Signed-off-by: Ziqi Chen <ziqichen@codeaurora.org>
---
 drivers/scsi/ufs/ufshcd.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e221add..3f807f7 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8686,8 +8686,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	if (ret)
 		goto set_dev_active;
 
-	ufshcd_vreg_set_lpm(hba);
-
 disable_clks:
 	/*
 	 * Call vendor specific suspend callback. As these callbacks may access
@@ -8711,6 +8709,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 					hba->clk_gating.state);
 	}
 
+	ufshcd_vreg_set_lpm(hba);
+
 	/* Put the host controller in low power mode if possible */
 	ufshcd_hba_vreg_set_lpm(hba);
 	goto out;
@@ -8778,18 +8778,18 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	old_link_state = hba->uic_link_state;
 
 	ufshcd_hba_vreg_set_hpm(hba);
+	ret = ufshcd_vreg_set_hpm(hba);
+	if (ret)
+		goto out;
+
 	/* Make sure clocks are enabled before accessing controller */
 	ret = ufshcd_setup_clocks(hba, true);
 	if (ret)
-		goto out;
+		goto disable_vreg;
 
 	/* enable the host irq as host controller would be active soon */
 	ufshcd_enable_irq(hba);
 
-	ret = ufshcd_vreg_set_hpm(hba);
-	if (ret)
-		goto disable_irq_and_vops_clks;
-
 	/*
 	 * Call vendor specific resume callback. As these callbacks may access
 	 * vendor specific host controller register space call them when the
@@ -8797,7 +8797,7 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	 */
 	ret = ufshcd_vops_resume(hba, pm_op);
 	if (ret)
-		goto disable_vreg;
+		goto disable_irq_and_vops_clks;
 
 	/* For DeepSleep, the only supported option is to have the link off */
 	WARN_ON(ufshcd_is_ufs_dev_deepsleep(hba) && !ufshcd_is_link_off(hba));
@@ -8864,8 +8864,6 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	ufshcd_link_state_transition(hba, old_link_state, 0);
 vendor_suspend:
 	ufshcd_vops_suspend(hba, pm_op);
-disable_vreg:
-	ufshcd_vreg_set_lpm(hba);
 disable_irq_and_vops_clks:
 	ufshcd_disable_irq(hba);
 	if (hba->clk_scaling.is_allowed)
@@ -8876,6 +8874,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 		trace_ufshcd_clk_gating(dev_name(hba->dev),
 					hba->clk_gating.state);
 	}
+disable_vreg:
+	ufshcd_vreg_set_lpm(hba);
 out:
 	hba->pm_op_in_progress = 0;
 	if (ret)
-- 
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