scsi: ufs: Refactor ufshcd_init/exit_clk_scaling/gating()

ufshcd_hba_exit() is always called after ufshcd_exit_clk_scaling() and
ufshcd_exit_clk_gating(). Move ufshcd_exit_clk_scaling/gating() to
ufshcd_hba_exit(). Meanwhile, add dedicated functions to initialize
and remove sysfs nodes of clock scaling/gating to make the code more
readable. Overall functionality remains same.

Link: https://lore.kernel.org/r/1611137065-14266-3-git-send-email-cang@codeaurora.orgReviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufshcd.c

@@ -1593,7 +1593,7 @@ static ssize_t ufshcd_clkscale_enable_store(struct device *dev,
 	return err ? err : count;
 }
 
-static void ufshcd_clkscaling_init_sysfs(struct ufs_hba *hba)
+static void ufshcd_init_clk_scaling_sysfs(struct ufs_hba *hba)
 {
 	hba->clk_scaling.enable_attr.show = ufshcd_clkscale_enable_show;
 	hba->clk_scaling.enable_attr.store = ufshcd_clkscale_enable_store;
@@ -1604,6 +1604,42 @@ static void ufshcd_clkscaling_init_sysfs(struct ufs_hba *hba)
 		dev_err(hba->dev, "Failed to create sysfs for clkscale_enable\n");
 }
 
+static void ufshcd_remove_clk_scaling_sysfs(struct ufs_hba *hba)
+{
+	if (hba->clk_scaling.enable_attr.attr.name)
+		device_remove_file(hba->dev, &hba->clk_scaling.enable_attr);
+}
+
+static void ufshcd_init_clk_scaling(struct ufs_hba *hba)
+{
+	char wq_name[sizeof("ufs_clkscaling_00")];
+
+	if (!ufshcd_is_clkscaling_supported(hba))
+		return;
+
+	INIT_WORK(&hba->clk_scaling.suspend_work,
+		  ufshcd_clk_scaling_suspend_work);
+	INIT_WORK(&hba->clk_scaling.resume_work,
+		  ufshcd_clk_scaling_resume_work);
+
+	snprintf(wq_name, sizeof(wq_name), "ufs_clkscaling_%d",
+		 hba->host->host_no);
+	hba->clk_scaling.workq = create_singlethread_workqueue(wq_name);
+
+	hba->clk_scaling.is_initialized = true;
+}
+
+static void ufshcd_exit_clk_scaling(struct ufs_hba *hba)
+{
+	if (!hba->clk_scaling.is_initialized)
+		return;
+
+	ufshcd_remove_clk_scaling_sysfs(hba);
+	destroy_workqueue(hba->clk_scaling.workq);
+	ufshcd_devfreq_remove(hba);
+	hba->clk_scaling.is_initialized = false;
+}
+
 static void ufshcd_ungate_work(struct work_struct *work)
 {
 	int ret;
@@ -1895,35 +1931,31 @@ static ssize_t ufshcd_clkgate_enable_store(struct device *dev,
 	return count;
 }
 
-static void ufshcd_init_clk_scaling(struct ufs_hba *hba)
+static void ufshcd_init_clk_gating_sysfs(struct ufs_hba *hba)
 {
-	char wq_name[sizeof("ufs_clkscaling_00")];
-
-	if (!ufshcd_is_clkscaling_supported(hba))
-		return;
-
-	if (!hba->clk_scaling.min_gear)
-		hba->clk_scaling.min_gear = UFS_HS_G1;
-
-	INIT_WORK(&hba->clk_scaling.suspend_work,
-		  ufshcd_clk_scaling_suspend_work);
-	INIT_WORK(&hba->clk_scaling.resume_work,
-		  ufshcd_clk_scaling_resume_work);
+	hba->clk_gating.delay_attr.show = ufshcd_clkgate_delay_show;
+	hba->clk_gating.delay_attr.store = ufshcd_clkgate_delay_store;
+	sysfs_attr_init(&hba->clk_gating.delay_attr.attr);
+	hba->clk_gating.delay_attr.attr.name = "clkgate_delay_ms";
+	hba->clk_gating.delay_attr.attr.mode = 0644;
+	if (device_create_file(hba->dev, &hba->clk_gating.delay_attr))
+		dev_err(hba->dev, "Failed to create sysfs for clkgate_delay\n");
 
-	snprintf(wq_name, sizeof(wq_name), "ufs_clkscaling_%d",
-		 hba->host->host_no);
-	hba->clk_scaling.workq = create_singlethread_workqueue(wq_name);
+	hba->clk_gating.enable_attr.show = ufshcd_clkgate_enable_show;
+	hba->clk_gating.enable_attr.store = ufshcd_clkgate_enable_store;
+	sysfs_attr_init(&hba->clk_gating.enable_attr.attr);
+	hba->clk_gating.enable_attr.attr.name = "clkgate_enable";
+	hba->clk_gating.enable_attr.attr.mode = 0644;
+	if (device_create_file(hba->dev, &hba->clk_gating.enable_attr))
+		dev_err(hba->dev, "Failed to create sysfs for clkgate_enable\n");
 }
 
-static void ufshcd_exit_clk_scaling(struct ufs_hba *hba)
+static void ufshcd_remove_clk_gating_sysfs(struct ufs_hba *hba)
 {
-	if (!ufshcd_is_clkscaling_supported(hba))
-		return;
-
-	if (hba->clk_scaling.enable_attr.attr.name)
-		device_remove_file(hba->dev, &hba->clk_scaling.enable_attr);
-	destroy_workqueue(hba->clk_scaling.workq);
-	ufshcd_devfreq_remove(hba);
+	if (hba->clk_gating.delay_attr.attr.name)
+		device_remove_file(hba->dev, &hba->clk_gating.delay_attr);
+	if (hba->clk_gating.enable_attr.attr.name)
+		device_remove_file(hba->dev, &hba->clk_gating.enable_attr);
 }
 
 static void ufshcd_init_clk_gating(struct ufs_hba *hba)
@@ -1944,34 +1976,21 @@ static void ufshcd_init_clk_gating(struct ufs_hba *hba)
 	hba->clk_gating.clk_gating_workq = alloc_ordered_workqueue(wq_name,
 					WQ_MEM_RECLAIM | WQ_HIGHPRI);
 
-	hba->clk_gating.is_enabled = true;
+	ufshcd_init_clk_gating_sysfs(hba);
 
-	hba->clk_gating.delay_attr.show = ufshcd_clkgate_delay_show;
-	hba->clk_gating.delay_attr.store = ufshcd_clkgate_delay_store;
-	sysfs_attr_init(&hba->clk_gating.delay_attr.attr);
-	hba->clk_gating.delay_attr.attr.name = "clkgate_delay_ms";
-	hba->clk_gating.delay_attr.attr.mode = 0644;
-	if (device_create_file(hba->dev, &hba->clk_gating.delay_attr))
-		dev_err(hba->dev, "Failed to create sysfs for clkgate_delay\n");
-
-	hba->clk_gating.enable_attr.show = ufshcd_clkgate_enable_show;
-	hba->clk_gating.enable_attr.store = ufshcd_clkgate_enable_store;
-	sysfs_attr_init(&hba->clk_gating.enable_attr.attr);
-	hba->clk_gating.enable_attr.attr.name = "clkgate_enable";
-	hba->clk_gating.enable_attr.attr.mode = 0644;
-	if (device_create_file(hba->dev, &hba->clk_gating.enable_attr))
-		dev_err(hba->dev, "Failed to create sysfs for clkgate_enable\n");
+	hba->clk_gating.is_enabled = true;
+	hba->clk_gating.is_initialized = true;
 }
 
 static void ufshcd_exit_clk_gating(struct ufs_hba *hba)
 {
-	if (!ufshcd_is_clkgating_allowed(hba))
+	if (!hba->clk_gating.is_initialized)
 		return;
-	device_remove_file(hba->dev, &hba->clk_gating.delay_attr);
-	device_remove_file(hba->dev, &hba->clk_gating.enable_attr);
+	ufshcd_remove_clk_gating_sysfs(hba);
 	cancel_work_sync(&hba->clk_gating.ungate_work);
 	cancel_delayed_work_sync(&hba->clk_gating.gate_work);
 	destroy_workqueue(hba->clk_gating.clk_gating_workq);
+	hba->clk_gating.is_initialized = false;
 }
 
 /* Must be called with host lock acquired */
@@ -7766,7 +7785,7 @@ static int ufshcd_add_lus(struct ufs_hba *hba)
 				goto out;
 
 			hba->clk_scaling.is_enabled = true;
-			ufshcd_clkscaling_init_sysfs(hba);
+			ufshcd_init_clk_scaling_sysfs(hba);
 		}
 	}
 
@@ -7954,7 +7973,6 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 	 */
 	if (ret) {
 		pm_runtime_put_sync(hba->dev);
-		ufshcd_exit_clk_scaling(hba);
 		ufshcd_hba_exit(hba);
 	} else {
 		ufshcd_clear_ua_wluns(hba);
@@ -8386,13 +8404,13 @@ static int ufshcd_hba_init(struct ufs_hba *hba)
 static void ufshcd_hba_exit(struct ufs_hba *hba)
 {
 	if (hba->is_powered) {
+		ufshcd_exit_clk_scaling(hba);
+		ufshcd_exit_clk_gating(hba);
+		if (hba->eh_wq)
+			destroy_workqueue(hba->eh_wq);
 		ufs_debugfs_hba_exit(hba);
 		ufshcd_variant_hba_exit(hba);
 		ufshcd_setup_vreg(hba, false);
-		ufshcd_suspend_clkscaling(hba);
-		if (ufshcd_is_clkscaling_supported(hba))
-			if (hba->devfreq)
-				ufshcd_suspend_clkscaling(hba);
 		ufshcd_setup_clocks(hba, false);
 		ufshcd_setup_hba_vreg(hba, false);
 		hba->is_powered = false;
@@ -9178,13 +9196,9 @@ void ufshcd_remove(struct ufs_hba *hba)
 	blk_mq_free_tag_set(&hba->tmf_tag_set);
 	blk_cleanup_queue(hba->cmd_queue);
 	scsi_remove_host(hba->host);
-	destroy_workqueue(hba->eh_wq);
 	/* disable interrupts */
 	ufshcd_disable_intr(hba, hba->intr_mask);
 	ufshcd_hba_stop(hba);
-
-	ufshcd_exit_clk_scaling(hba);
-	ufshcd_exit_clk_gating(hba);
 	ufshcd_hba_exit(hba);
 }
 EXPORT_SYMBOL_GPL(ufshcd_remove);
@@ -9385,7 +9399,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	err = devm_request_irq(dev, irq, ufshcd_intr, IRQF_SHARED, UFSHCD, hba);
 	if (err) {
 		dev_err(hba->dev, "request irq failed\n");
-		goto exit_gating;
+		goto out_disable;
 	} else {
 		hba->is_irq_enabled = true;
 	}
@@ -9393,7 +9407,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	err = scsi_add_host(host, hba->dev);
 	if (err) {
 		dev_err(hba->dev, "scsi_add_host failed\n");
-		goto exit_gating;
+		goto out_disable;
 	}
 
 	hba->cmd_queue = blk_mq_init_queue(&hba->host->tag_set);
@@ -9476,10 +9490,6 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	blk_cleanup_queue(hba->cmd_queue);
 out_remove_scsi_host:
 	scsi_remove_host(hba->host);
-exit_gating:
-	ufshcd_exit_clk_scaling(hba);
-	ufshcd_exit_clk_gating(hba);
-	destroy_workqueue(hba->eh_wq);
 out_disable:
 	hba->is_irq_enabled = false;
 	ufshcd_hba_exit(hba);

drivers/scsi/ufs/ufshcd.h

@@ -383,6 +383,7 @@ enum clk_gating_state {
  * @delay_attr: sysfs attribute to control delay_attr
  * @enable_attr: sysfs attribute to enable/disable clock gating
  * @is_enabled: Indicates the current status of clock gating
+ * @is_initialized: Indicates whether clock gating is initialized or not
  * @active_reqs: number of requests that are pending and should be waited for
  * completion before gating clocks.
  */
@@ -395,6 +396,7 @@ struct ufs_clk_gating {
 	struct device_attribute delay_attr;
 	struct device_attribute enable_attr;
 	bool is_enabled;
+	bool is_initialized;
 	int active_reqs;
 	struct workqueue_struct *clk_gating_workq;
 };
@@ -423,6 +425,7 @@ struct ufs_saved_pwr_info {
 		clkscale_enable sysfs node
  * @is_allowed: tracks if scaling is currently allowed or not, used to block
 		clock scaling which is not invoked from devfreq governor
+ * @is_initialized: Indicates whether clock scaling is initialized or not
  * @is_busy_started: tracks if busy period has started or not
  * @is_suspended: tracks if devfreq is suspended or not
  */
@@ -439,6 +442,7 @@ struct ufs_clk_scaling {
 	u32 min_gear;
 	bool is_enabled;
 	bool is_allowed;
+	bool is_initialized;
 	bool is_busy_started;
 	bool is_suspended;
 };