[PATCH v1 1/2] scsi: ufs: Introduce bus voting vendor ops

[PATCH v1 1/2] scsi: ufs: Introduce bus voting vendor ops

[Can Guo]

Some vendors need to vote for bus bandwidth when bus clocks are changed,
hence introduce the bus voting vendor ops so that UFS driver can use it.

Signed-off-by: Can Guo <cang@codeaurora.org>
---
 drivers/scsi/ufs/ufshcd.c | 19 ++++++++++++++++++-
 drivers/scsi/ufs/ufshcd.h |  9 +++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c28c144..ec13aaf 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7289,6 +7289,13 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 	if (list_empty(head))
 		goto out;
 
+	/* call vendor specific bus vote before enabling the clocks */
+	if (on) {
+		ret = ufshcd_vops_set_bus_vote(hba, on);
+		if (ret)
+			return ret;
+	}
+
 	/*
 	 * vendor specific setup_clocks ops may depend on clocks managed by
 	 * this standard driver hence call the vendor specific setup_clocks
@@ -7330,11 +7337,21 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 	if (on) {
 		ret = ufshcd_vops_setup_clocks(hba, on, POST_CHANGE);
 		if (ret)
-			return ret;
+			goto out;
 	}
 
+	/*
+	 * call vendor specific bus vote to remove the vote after
+	 * disabling the clocks.
+	 */
+	if (!on)
+		ret = ufshcd_vops_set_bus_vote(hba, on);
+
 out:
 	if (ret) {
+		if (on)
+			/* Can't do much if this fails */
+			(void) ufshcd_vops_set_bus_vote(hba, false);
 		list_for_each_entry(clki, head, list) {
 			if (!IS_ERR_OR_NULL(clki->clk) && clki->enabled)
 				clk_disable_unprepare(clki->clk);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index e0fe247..7eb4174 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -297,6 +297,7 @@ struct ufs_pwr_mode_info {
  * @suspend: called during host controller PM callback
  * @resume: called during host controller PM callback
  * @dbg_register_dump: used to dump controller debug information
+ * @set_bus_vote: called to vote for the required bus bandwidth
  * @phy_initialization: used to initialize phys
  * @device_reset: called to issue a reset pulse on the UFS device
  */
@@ -326,6 +327,7 @@ struct ufs_hba_variant_ops {
 	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op);
 	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
 	void	(*dbg_register_dump)(struct ufs_hba *hba);
+	int	(*set_bus_vote)(struct ufs_hba *, bool);
 	int	(*phy_initialization)(struct ufs_hba *);
 	void	(*device_reset)(struct ufs_hba *hba);
 };
@@ -1082,6 +1084,13 @@ static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
 		hba->vops->dbg_register_dump(hba);
 }
 
+static inline int ufshcd_vops_set_bus_vote(struct ufs_hba *hba, bool on)
+{
+	if (hba->vops && hba->vops->set_bus_vote)
+		return hba->vops->set_bus_vote(hba, on);
+	return 0;
+}
+
 static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
 {
 	if (hba->vops && hba->vops->device_reset)
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH v1 2/2] scsi: ufs-qcom: Export bus bandwidth voting ops

[Can Guo]

Export bus bandwidth voting ops so that UFS driver can vote for
bus bandwidth change through vendor ops.

Signed-off-by: Can Guo <cang@codeaurora.org>
---
 drivers/scsi/ufs/ufs-qcom.c | 53 ++++++++++++++++++++++++++++++---------------
 1 file changed, 35 insertions(+), 18 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index a5b7148..0a6fac9 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -38,7 +38,6 @@ enum {
 
 static struct ufs_qcom_host *ufs_qcom_hosts[MAX_UFS_QCOM_HOSTS];
 
-static int ufs_qcom_set_bus_vote(struct ufs_qcom_host *host, int vote);
 static void ufs_qcom_get_default_testbus_cfg(struct ufs_qcom_host *host);
 static int ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
 						       u32 clk_cycles);
@@ -630,7 +629,7 @@ static void ufs_qcom_get_speed_mode(struct ufs_pa_layer_attr *p, char *result)
 	}
 }
 
-static int ufs_qcom_set_bus_vote(struct ufs_qcom_host *host, int vote)
+static int __ufs_qcom_set_bus_vote(struct ufs_qcom_host *host, int vote)
 {
 	int err = 0;
 
@@ -661,7 +660,7 @@ static int ufs_qcom_update_bus_bw_vote(struct ufs_qcom_host *host)
 
 	vote = ufs_qcom_get_bus_vote(host, mode);
 	if (vote >= 0)
-		err = ufs_qcom_set_bus_vote(host, vote);
+		err = __ufs_qcom_set_bus_vote(host, vote);
 	else
 		err = vote;
 
@@ -672,6 +671,35 @@ static int ufs_qcom_update_bus_bw_vote(struct ufs_qcom_host *host)
 	return err;
 }
 
+static int ufs_qcom_set_bus_vote(struct ufs_hba *hba, bool on)
+{
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	int vote, err;
+
+	/*
+	 * In case ufs_qcom_init() is not yet done, simply ignore.
+	 * This ufs_qcom_set_bus_vote() shall be called from
+	 * ufs_qcom_init() after init is done.
+	 */
+	if (!host)
+		return 0;
+
+	if (on) {
+		vote = host->bus_vote.saved_vote;
+		if (vote == host->bus_vote.min_bw_vote)
+			ufs_qcom_update_bus_bw_vote(host);
+	} else {
+		vote = host->bus_vote.min_bw_vote;
+	}
+
+	err = __ufs_qcom_set_bus_vote(host, vote);
+	if (err)
+		dev_err(hba->dev, "%s: set bus vote failed %d\n",
+				__func__, err);
+
+	return err;
+}
+
 static ssize_t
 show_ufs_to_mem_max_bus_bw(struct device *dev, struct device_attribute *attr,
 			char *buf)
@@ -748,7 +776,7 @@ static int ufs_qcom_update_bus_bw_vote(struct ufs_qcom_host *host)
 	return 0;
 }
 
-static int ufs_qcom_set_bus_vote(struct ufs_qcom_host *host, int vote)
+static int ufs_qcom_set_bus_vote(struct ufs_hba *host, bool on)
 {
 	return 0;
 }
@@ -986,8 +1014,6 @@ static int ufs_qcom_setup_clocks(struct ufs_hba *hba, bool on,
 				 enum ufs_notify_change_status status)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
-	int err;
-	int vote = 0;
 
 	/*
 	 * In case ufs_qcom_init() is not yet done, simply ignore.
@@ -1001,25 +1027,14 @@ static int ufs_qcom_setup_clocks(struct ufs_hba *hba, bool on,
 		/* enable the device ref clock for HS mode*/
 		if (ufshcd_is_hs_mode(&hba->pwr_info))
 			ufs_qcom_dev_ref_clk_ctrl(host, true);
-		vote = host->bus_vote.saved_vote;
-		if (vote == host->bus_vote.min_bw_vote)
-			ufs_qcom_update_bus_bw_vote(host);
-
 	} else if (!on && (status == PRE_CHANGE)) {
 		if (!ufs_qcom_is_link_active(hba)) {
 			/* disable device ref_clk */
 			ufs_qcom_dev_ref_clk_ctrl(host, false);
 		}
-
-		vote = host->bus_vote.min_bw_vote;
 	}
 
-	err = ufs_qcom_set_bus_vote(host, vote);
-	if (err)
-		dev_err(hba->dev, "%s: set bus vote failed %d\n",
-				__func__, err);
-
-	return err;
+	return 0;
 }
 
 static int
@@ -1185,6 +1200,7 @@ static int ufs_qcom_init(struct ufs_hba *hba)
 	ufs_qcom_set_caps(hba);
 	ufs_qcom_advertise_quirks(hba);
 
+	ufs_qcom_set_bus_vote(hba, true);
 	ufs_qcom_setup_clocks(hba, true, POST_CHANGE);
 
 	if (hba->dev->id < MAX_UFS_QCOM_HOSTS)
@@ -1597,6 +1613,7 @@ static void ufs_qcom_device_reset(struct ufs_hba *hba)
 	.suspend		= ufs_qcom_suspend,
 	.resume			= ufs_qcom_resume,
 	.dbg_register_dump	= ufs_qcom_dump_dbg_regs,
+	.set_bus_vote		= ufs_qcom_set_bus_vote,
 	.device_reset		= ufs_qcom_device_reset,
 };
 
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project