usb: cdns3: drd: simplify *switch_gadet and *switch_host

Patch split function cdns3_drd_switch_gadget and
cdns3_drd_switch_host into:
- cdns3_drd_host_on
- cdns3_drd_host_off
- cdns3_drd_gadget_on
- cdns3_drd_gadgett_off

These functions don't have any shared code so it's better to
have smaller, faster and easier functions.
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

drivers/usb/cdns3/drd.c

@@ -124,85 +124,97 @@ static void cdns3_otg_enable_irq(struct cdns3 *cdns)
 }
 
 /**
- * cdns3_drd_switch_host - start/stop host
- * @cdns: Pointer to controller context structure
- * @on: 1 for start, 0 for stop
+ * cdns3_drd_host_on - start host.
+ * @cdns: Pointer to controller context structure.
  *
- * Returns 0 on success otherwise negative errno
+ * Returns 0 on success otherwise negative errno.
  */
-int cdns3_drd_switch_host(struct cdns3 *cdns, int on)
+int cdns3_drd_host_on(struct cdns3 *cdns)
 {
-	int ret, val;
+	u32 val;
+	int ret;
 
-	/* switch OTG core */
-	if (on) {
-		writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS,
-		       &cdns->otg_regs->cmd);
-
-		dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
-		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
-						val & OTGSTS_XHCI_READY,
-						1, 100000);
-		if (ret) {
-			dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
-			return ret;
-		}
-	} else {
-		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
-		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
-		       &cdns->otg_regs->cmd);
-		/* Waiting till H_IDLE state.*/
-		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
-					  !(val & OTGSTATE_HOST_STATE_MASK),
-					  1, 2000000);
-	}
+	/* Enable host mode. */
+	writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS,
+	       &cdns->otg_regs->cmd);
 
-	return 0;
+	dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
+	ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
+					val & OTGSTS_XHCI_READY, 1, 100000);
+
+	if (ret)
+		dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
+
+	return ret;
 }
 
 /**
- * cdns3_drd_switch_gadget - start/stop gadget
- * @cdns: Pointer to controller context structure
- * @on: 1 for start, 0 for stop
+ * cdns3_drd_host_off - stop host.
+ * @cdns: Pointer to controller context structure.
+ */
+void cdns3_drd_host_off(struct cdns3 *cdns)
+{
+	u32 val;
+
+	writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
+	       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
+	       &cdns->otg_regs->cmd);
+
+	/* Waiting till H_IDLE state.*/
+	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
+				  !(val & OTGSTATE_HOST_STATE_MASK),
+				  1, 2000000);
+}
+
+/**
+ * cdns3_drd_gadget_on - start gadget.
+ * @cdns: Pointer to controller context structure.
  *
  * Returns 0 on success otherwise negative errno
  */
-int cdns3_drd_switch_gadget(struct cdns3 *cdns, int on)
+int cdns3_drd_gadget_on(struct cdns3 *cdns)
 {
 	int ret, val;
 	u32 reg = OTGCMD_OTG_DIS;
 
 	/* switch OTG core */
-	if (on) {
-		writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
+	writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
 
-		dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
+	dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
 
-		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
-						val & OTGSTS_DEV_READY,
-						1, 100000);
-		if (ret) {
-			dev_err(cdns->dev, "timeout waiting for dev_ready\n");
-			return ret;
-		}
-	} else {
-		/*
-		 * driver should wait at least 10us after disabling Device
-		 * before turning-off Device (DEV_BUS_DROP)
-		 */
-		usleep_range(20, 30);
-		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
-		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
-		       &cdns->otg_regs->cmd);
-		/* Waiting till DEV_IDLE state.*/
-		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
-					  !(val & OTGSTATE_DEV_STATE_MASK),
-					  1, 2000000);
+	ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
+					val & OTGSTS_DEV_READY,
+					1, 100000);
+	if (ret) {
+		dev_err(cdns->dev, "timeout waiting for dev_ready\n");
+		return ret;
 	}
 
 	return 0;
 }
 
+/**
+ * cdns3_drd_gadget_off - stop gadget.
+ * @cdns: Pointer to controller context structure.
+ */
+void cdns3_drd_gadget_off(struct cdns3 *cdns)
+{
+	u32 val;
+
+	/*
+	 * Driver should wait at least 10us after disabling Device
+	 * before turning-off Device (DEV_BUS_DROP).
+	 */
+	usleep_range(20, 30);
+	writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
+	       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
+	       &cdns->otg_regs->cmd);
+	/* Waiting till DEV_IDLE state.*/
+	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
+				  !(val & OTGSTATE_DEV_STATE_MASK),
+				  1, 2000000);
+}
+
 /**
  * cdns3_init_otg_mode - initialize drd controller
  * @cdns: Pointer to controller context structure

drivers/usb/cdns3/drd.h

@@ -163,8 +163,10 @@ int cdns3_get_vbus(struct cdns3 *cdns);
 int cdns3_drd_init(struct cdns3 *cdns);
 int cdns3_drd_exit(struct cdns3 *cdns);
 int cdns3_drd_update_mode(struct cdns3 *cdns);
-int cdns3_drd_switch_gadget(struct cdns3 *cdns, int on);
-int cdns3_drd_switch_host(struct cdns3 *cdns, int on);
+int cdns3_drd_gadget_on(struct cdns3 *cdns);
+void cdns3_drd_gadget_off(struct cdns3 *cdns);
+int cdns3_drd_host_on(struct cdns3 *cdns);
+void cdns3_drd_host_off(struct cdns3 *cdns);
 int cdns3_set_mode(struct cdns3 *cdns, enum usb_dr_mode mode);
 
 #endif /* __LINUX_CDNS3_DRD */

drivers/usb/cdns3/gadget.c

@@ -3017,7 +3017,7 @@ void cdns3_gadget_exit(struct cdns3 *cdns)
 	kfree(priv_dev->zlp_buf);
 	kfree(priv_dev);
 	cdns->gadget_dev = NULL;
-	cdns3_drd_switch_gadget(cdns, 0);
+	cdns3_drd_gadget_off(cdns);
 }
 
 static int cdns3_gadget_start(struct cdns3 *cdns)
@@ -3148,7 +3148,7 @@ static int __cdns3_gadget_init(struct cdns3 *cdns)
 		return ret;
 	}
 
-	cdns3_drd_switch_gadget(cdns, 1);
+	cdns3_drd_gadget_on(cdns);
 	pm_runtime_get_sync(cdns->dev);
 
 	ret = cdns3_gadget_start(cdns);

drivers/usb/cdns3/host.c

@@ -19,7 +19,7 @@ static int __cdns3_host_init(struct cdns3 *cdns)
 	struct platform_device *xhci;
 	int ret;
 
-	cdns3_drd_switch_host(cdns, 1);
+	cdns3_drd_host_on(cdns);
 
 	xhci = platform_device_alloc("xhci-hcd", PLATFORM_DEVID_AUTO);
 	if (!xhci) {
@@ -53,7 +53,7 @@ static void cdns3_host_exit(struct cdns3 *cdns)
 {
 	platform_device_unregister(cdns->host_dev);
 	cdns->host_dev = NULL;
-	cdns3_drd_switch_host(cdns, 0);
+	cdns3_drd_host_off(cdns);
 }
 
 int cdns3_host_init(struct cdns3 *cdns)