[PATCH v3 1/2] scsi: ufs: Refactor ufshcd_setup_clocks() to remove skip_ref_clk

[Can Guo]

Remove the param skip_ref_clk from __ufshcd_setup_clocks(), but keep a flag
in struct ufs_clk_info to tell whether a clock can be disabled or not while
the link is active.

Reviewed-by: Hongwu Su<hongwus at codeaurora.org>
Reviewed-by: Bean Huo <beanhuo at micron.com>
Reviewed-by: Stanley Chu <stanley.chu at mediatek.com>
Signed-off-by: Can Guo <cang at codeaurora.org>
---
 drivers/scsi/ufs/ufshcd-pltfrm.c |  2 ++
 drivers/scsi/ufs/ufshcd.c        | 29 +++++++++--------------------
 drivers/scsi/ufs/ufshcd.h        |  3 +++
 3 files changed, 14 insertions(+), 20 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 3db0af6..873ef14 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -92,6 +92,8 @@ static int ufshcd_parse_clock_info(struct ufs_hba *hba)
 		clki->min_freq = clkfreq[i];
 		clki->max_freq = clkfreq[i+1];
 		clki->name = kstrdup(name, GFP_KERNEL);
+		if (!strcmp(name, "ref_clk"))
+			clki->keep_link_active = true;
 		dev_dbg(dev, "%s: min %u max %u name %s\n", "freq-table-hz",
 				clki->min_freq, clki->max_freq, clki->name);
 		list_add_tail(&clki->list, &hba->clk_list_head);
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index a7857f6..44254c9 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -221,8 +221,6 @@ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd);
 static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);
 static void ufshcd_hba_exit(struct ufs_hba *hba);
 static int ufshcd_probe_hba(struct ufs_hba *hba, bool async);
-static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
-				 bool skip_ref_clk);
 static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on);
 static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba);
 static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba);
@@ -1707,11 +1705,7 @@ static void ufshcd_gate_work(struct work_struct *work)
 
 	ufshcd_disable_irq(hba);
 
-	if (!ufshcd_is_link_active(hba))
-		ufshcd_setup_clocks(hba, false);
-	else
-		/* If link is active, device ref_clk can't be switched off */
-		__ufshcd_setup_clocks(hba, false, true);
+	ufshcd_setup_clocks(hba, false);
 
 	/*
 	 * In case you are here to cancel this work the gating state
@@ -7990,8 +7984,7 @@ static int ufshcd_init_hba_vreg(struct ufs_hba *hba)
 	return 0;
 }
 
-static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
-					bool skip_ref_clk)
+static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
 {
 	int ret = 0;
 	struct ufs_clk_info *clki;
@@ -8009,7 +8002,12 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 
 	list_for_each_entry(clki, head, list) {
 		if (!IS_ERR_OR_NULL(clki->clk)) {
-			if (skip_ref_clk && !strcmp(clki->name, "ref_clk"))
+			/*
+			 * Don't disable clocks which are needed
+			 * to keep the link active.
+			 */
+			if (ufshcd_is_link_active(hba) &&
+			    clki->keep_link_active)
 				continue;
 
 			clk_state_changed = on ^ clki->enabled;
@@ -8054,11 +8052,6 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 	return ret;
 }
 
-static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
-{
-	return  __ufshcd_setup_clocks(hba, on, false);
-}
-
 static int ufshcd_init_clocks(struct ufs_hba *hba)
 {
 	int ret = 0;
@@ -8577,11 +8570,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	 */
 	ufshcd_disable_irq(hba);
 
-	if (!ufshcd_is_link_active(hba))
-		ufshcd_setup_clocks(hba, false);
-	else
-		/* If link is active, device ref_clk can't be switched off */
-		__ufshcd_setup_clocks(hba, false, true);
+	ufshcd_setup_clocks(hba, false);
 
 	if (ufshcd_is_clkgating_allowed(hba)) {
 		hba->clk_gating.state = CLKS_OFF;
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 66e5338..6f0f2d4 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -229,6 +229,8 @@ struct ufs_dev_cmd {
  * @max_freq: maximum frequency supported by the clock
  * @min_freq: min frequency that can be used for clock scaling
  * @curr_freq: indicates the current frequency that it is set to
+ * @keep_link_active: indicates that the clk should not be disabled if
+		      link is active
  * @enabled: variable to check against multiple enable/disable
  */
 struct ufs_clk_info {
@@ -238,6 +240,7 @@ struct ufs_clk_info {
 	u32 max_freq;
 	u32 min_freq;
 	u32 curr_freq;
+	bool keep_link_active;
 	bool enabled;
 };
 
-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.