[PATCH v4 0/9] usb: some PM changes for cdns3 and xhci-plat

[PATCH v4 0/9] usb: some PM changes for cdns3 and xhci-plat

[Peter Chen]

Hi Felipe & Mathias,

In this series, it adds cdns3 runtime PM support as well as some
xhci-plat changes, and verified at NXP i.MX8QM and i.MX8QXP platforms.

Patch 1-3: add main runtime PM support for cdns3 core and imx glue layer
Patch 4-9: add platform data support and two quirks for xhci-plat.c.
- .suspend_quirk for platform special sequence between xhci_bus_suspend
and xhci_suspend.
- add XHCI_SKIP_PHY_INIT quirk for skip PHY management from HCD core.

Changes for v4:
- Address Jun Li's comments for cdns3 core changes [Patch 2]
- Some small fixes for cdns3-imx for CLK_125_REQ bit
- Rebase the latest usb-next

Changes for v3:
Add Jun Li’s reviewed-by [Patch 1 and Patch 6]
Add Mathias’s acked-by [Patch 4-6]
Some wakeup logic improvement [Patch 2]
Add dedicated wakeup interrupt for core, and improve the commit log [Patch]
Fix build error found by kbuild test robot [Patch 3]
Using xhci_plat_priv quirk for skip PHY initialization [patch 7, patch 9]
Some other typo and tiny improvements

Changes for v2:
- Add the 1st patch. Without it, the build on the usb-next will fail.
- Change the subject for cover letter a little to reflect all contents.

Peter Chen (9):
  usb: cdns3: introduce cdns3_set_phy_power API
  usb: cdns3: add runtime PM support
  usb: cdns3: imx: add glue layer runtime pm implementation
  usb: host: xhci-plat: add platform data support
  usb: host: xhci-plat: add .suspend_quirk for struct xhci_plat_priv
  usb: host: xhci-plat: delete the unnecessary code
  usb: host: xhci-plat: add priv quirk for skip PHY initialization
  usb: cdns3: host: add .suspend_quirk for xhci-plat.c
  usb: cdns3: host: add xhci_plat_priv quirk XHCI_SKIP_PHY_INIT

 drivers/usb/cdns3/cdns3-imx.c   | 203 ++++++++++++++++++++++++++++++--
 drivers/usb/cdns3/core.c        | 197 ++++++++++++++++++++++++++-----
 drivers/usb/cdns3/core.h        |  16 +++
 drivers/usb/cdns3/drd.c         |   3 +
 drivers/usb/cdns3/gadget.c      |   4 +
 drivers/usb/cdns3/host-export.h |   6 +
 drivers/usb/cdns3/host.c        |  48 ++++++++
 drivers/usb/host/xhci-plat.c    |  36 +++++-
 drivers/usb/host/xhci-plat.h    |   1 +
 drivers/usb/host/xhci.h         |   1 +
 10 files changed, 467 insertions(+), 48 deletions(-)

-- 
2.17.1

[PATCH v4 1/9] usb: cdns3: introduce cdns3_set_phy_power API

[Peter Chen]

Since we have both USB2 and USB3 PHYs for cdns3 controller, it is
better we have a unity API to handle both USB2 and USB3's power, it
could simplify code for error handling and further power management
implementation.

Reviewed-by: Jun Li <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/core.c | 44 ++++++++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 15 deletions(-)

diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
index 19bbb5b7e6b6..bfd09aa98c12 100644
--- a/drivers/usb/cdns3/core.c
+++ b/drivers/usb/cdns3/core.c
@@ -384,6 +384,28 @@ static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role)
 	return ret;
 }
 
+static int cdns3_set_phy_power(struct cdns3 *cdns, bool on)
+{
+	int ret = 0;
+
+	if (on) {
+		ret = phy_power_on(cdns->usb2_phy);
+		if (ret)
+			return ret;
+
+		ret = phy_power_on(cdns->usb3_phy);
+		if (ret) {
+			phy_power_off(cdns->usb2_phy);
+			return ret;
+		}
+	} else {
+		phy_power_off(cdns->usb3_phy);
+		phy_power_off(cdns->usb2_phy);
+	}
+
+	return 0;
+}
+
 /**
  * cdns3_probe - probe for cdns3 core device
  * @pdev: Pointer to cdns3 core platform device
@@ -477,14 +499,10 @@ static int cdns3_probe(struct platform_device *pdev)
 	if (ret)
 		goto err1;
 
-	ret = phy_power_on(cdns->usb2_phy);
+	ret = cdns3_set_phy_power(cdns, true);
 	if (ret)
 		goto err2;
 
-	ret = phy_power_on(cdns->usb3_phy);
-	if (ret)
-		goto err3;
-
 	sw_desc.set = cdns3_role_set;
 	sw_desc.get = cdns3_role_get;
 	sw_desc.allow_userspace_control = true;
@@ -496,16 +514,16 @@ static int cdns3_probe(struct platform_device *pdev)
 	if (IS_ERR(cdns->role_sw)) {
 		ret = PTR_ERR(cdns->role_sw);
 		dev_warn(dev, "Unable to register Role Switch\n");
-		goto err4;
+		goto err3;
 	}
 
 	ret = cdns3_drd_init(cdns);
 	if (ret)
-		goto err5;
+		goto err4;
 
 	ret = cdns3_core_init_role(cdns);
 	if (ret)
-		goto err5;
+		goto err4;
 
 	device_set_wakeup_capable(dev, true);
 	pm_runtime_set_active(dev);
@@ -522,14 +540,11 @@ static int cdns3_probe(struct platform_device *pdev)
 	dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
 
 	return 0;
-err5:
+err4:
 	cdns3_drd_exit(cdns);
 	usb_role_switch_unregister(cdns->role_sw);
-err4:
-	phy_power_off(cdns->usb3_phy);
-
 err3:
-	phy_power_off(cdns->usb2_phy);
+	cdns3_set_phy_power(cdns, false);
 err2:
 	phy_exit(cdns->usb3_phy);
 err1:
@@ -553,8 +568,7 @@ static int cdns3_remove(struct platform_device *pdev)
 	pm_runtime_put_noidle(&pdev->dev);
 	cdns3_exit_roles(cdns);
 	usb_role_switch_unregister(cdns->role_sw);
-	phy_power_off(cdns->usb2_phy);
-	phy_power_off(cdns->usb3_phy);
+	cdns3_set_phy_power(cdns, false);
 	phy_exit(cdns->usb2_phy);
 	phy_exit(cdns->usb3_phy);
 	return 0;
-- 
2.17.1

[PATCH v4 2/9] usb: cdns3: add runtime PM support

[Peter Chen]

Introduce runtime PM and wakeup interrupt handler for cdns3,
the runtime PM is default off since other cdns3 may not
implement glue layer support for runtime PM.

One typical wakeup event use case is xHCI runtime suspend will clear
USBCMD.RS bit, after that the xHCI will not trigger any interrupts,
so its parent (cdns core device) needs to resume xHCI device when
any (wakeup) events occurs at host port.

When the controller is in low power mode, the lpm flag will be set.
The interrupt triggered later than lpm flag is set considers as
wakeup interrupt and handled at cdns_wakeup_irq. Once the wakeup
occurs, it first disables interrupt to avoid later interrupt
occurrence since the controller is in low power mode at that
time, and access registers may be invalid at that time. At wakeup
handler, it will call pm_request_resume to wakeup xHCI device, and
at runtime resume handler, it will enable interrupt again.

The API platform_suspend is introduced for glue layer to implement
platform specific PM sequence.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/core.c   | 153 ++++++++++++++++++++++++++++++++-----
 drivers/usb/cdns3/core.h   |  16 ++++
 drivers/usb/cdns3/drd.c    |   3 +
 drivers/usb/cdns3/gadget.c |   4 +
 drivers/usb/cdns3/host.c   |   7 ++
 5 files changed, 166 insertions(+), 17 deletions(-)

diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
index bfd09aa98c12..2fedb8044d8f 100644
--- a/drivers/usb/cdns3/core.c
+++ b/drivers/usb/cdns3/core.c
@@ -406,6 +406,30 @@ static int cdns3_set_phy_power(struct cdns3 *cdns, bool on)
 	return 0;
 }
 
+/**
+ * cdns3_wakeup_irq - interrupt handler for wakeup events
+ *
+ * @irq: irq number for cdns3 core device
+ * @data: structure of cdns3
+ *
+ * Returns IRQ_HANDLED or IRQ_NONE
+ */
+static irqreturn_t cdns3_wakeup_irq(int irq, void *data)
+{
+	struct cdns3 *cdns = data;
+
+	if (cdns->in_lpm) {
+		disable_irq_nosync(irq);
+		cdns->wakeup_pending = true;
+		if ((cdns->role == USB_ROLE_HOST) && cdns->host_dev)
+			pm_request_resume(&cdns->host_dev->dev);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
 /**
  * cdns3_probe - probe for cdns3 core device
  * @pdev: Pointer to cdns3 core platform device
@@ -432,6 +456,7 @@ static int cdns3_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	cdns->dev = dev;
+	cdns->pdata = dev_get_platdata(dev);
 
 	platform_set_drvdata(pdev, cdns);
 
@@ -481,6 +506,15 @@ static int cdns3_probe(struct platform_device *pdev)
 
 	cdns->otg_res = *res;
 
+	cdns->wakeup_irq = platform_get_irq_byname_optional(pdev, "wakeup");
+	if (cdns->wakeup_irq == -EPROBE_DEFER)
+		return cdns->wakeup_irq;
+
+	if (cdns->wakeup_irq < 0) {
+		dev_dbg(dev, "couldn't get wakeup irq\n");
+		cdns->wakeup_irq = 0x0;
+	}
+
 	mutex_init(&cdns->mutex);
 
 	cdns->usb2_phy = devm_phy_optional_get(dev, "cdns3,usb2-phy");
@@ -517,6 +551,19 @@ static int cdns3_probe(struct platform_device *pdev)
 		goto err3;
 	}
 
+	if (cdns->wakeup_irq) {
+		ret = devm_request_threaded_irq(cdns->dev, cdns->wakeup_irq,
+						cdns3_wakeup_irq,
+						NULL,
+						IRQF_SHARED,
+						dev_name(cdns->dev), cdns);
+
+		if (ret) {
+			dev_err(cdns->dev, "couldn't register wakeup irq handler\n");
+			goto err3;
+		}
+	}
+
 	ret = cdns3_drd_init(cdns);
 	if (ret)
 		goto err4;
@@ -525,9 +572,11 @@ static int cdns3_probe(struct platform_device *pdev)
 	if (ret)
 		goto err4;
 
+	spin_lock_init(&cdns->lock);
 	device_set_wakeup_capable(dev, true);
 	pm_runtime_set_active(dev);
 	pm_runtime_enable(dev);
+	pm_runtime_forbid(dev);
 
 	/*
 	 * The controller needs less time between bus and controller suspend,
@@ -574,52 +623,122 @@ static int cdns3_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_PM
 
-static int cdns3_suspend(struct device *dev)
+static int cdns3_set_platform_suspend(struct device *dev,
+		bool suspend, bool wakeup)
+{
+	struct cdns3 *cdns = dev_get_drvdata(dev);
+	int ret = 0;
+
+	if (cdns->pdata && cdns->pdata->platform_suspend)
+		ret = cdns->pdata->platform_suspend(dev, suspend, wakeup);
+
+	return ret;
+}
+
+static int cdns3_controller_suspend(struct device *dev, pm_message_t msg)
 {
 	struct cdns3 *cdns = dev_get_drvdata(dev);
+	bool wakeup;
 	unsigned long flags;
 
-	if (cdns->role == USB_ROLE_HOST)
+	if (cdns->in_lpm)
 		return 0;
 
-	if (pm_runtime_status_suspended(dev))
-		pm_runtime_resume(dev);
+	if (PMSG_IS_AUTO(msg))
+		wakeup = true;
+	else
+		wakeup = device_may_wakeup(dev);
 
-	if (cdns->roles[cdns->role]->suspend) {
-		spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
-		cdns->roles[cdns->role]->suspend(cdns, false);
-		spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
-	}
+	cdns3_set_platform_suspend(cdns->dev, true, wakeup);
+	cdns3_set_phy_power(cdns, false);
+	spin_lock_irqsave(&cdns->lock, flags);
+	cdns->in_lpm = true;
+	spin_unlock_irqrestore(&cdns->lock, flags);
+	dev_dbg(cdns->dev, "%s ends\n", __func__);
 
 	return 0;
 }
 
-static int cdns3_resume(struct device *dev)
+static int cdns3_controller_resume(struct device *dev, pm_message_t msg)
 {
 	struct cdns3 *cdns = dev_get_drvdata(dev);
+	int ret;
 	unsigned long flags;
 
-	if (cdns->role == USB_ROLE_HOST)
+	if (!cdns->in_lpm)
 		return 0;
 
-	if (cdns->roles[cdns->role]->resume) {
-		spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
+	ret = cdns3_set_phy_power(cdns, true);
+	if (ret)
+		return ret;
+
+	cdns3_set_platform_suspend(cdns->dev, false, false);
+
+	spin_lock_irqsave(&cdns->lock, flags);
+	if (cdns->roles[cdns->role]->resume && !PMSG_IS_AUTO(msg))
 		cdns->roles[cdns->role]->resume(cdns, false);
-		spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
+
+	cdns->in_lpm = false;
+	spin_unlock_irqrestore(&cdns->lock, flags);
+	if (cdns->wakeup_pending) {
+		cdns->wakeup_pending = false;
+		enable_irq(cdns->wakeup_irq);
+	}
+	dev_dbg(cdns->dev, "%s ends\n", __func__);
+
+	return ret;
+}
+
+static int cdns3_runtime_suspend(struct device *dev)
+{
+	return cdns3_controller_suspend(dev, PMSG_AUTO_SUSPEND);
+}
+
+static int cdns3_runtime_resume(struct device *dev)
+{
+	return cdns3_controller_resume(dev, PMSG_AUTO_RESUME);
+}
+#ifdef CONFIG_PM_SLEEP
+
+static int cdns3_suspend(struct device *dev)
+{
+	struct cdns3 *cdns = dev_get_drvdata(dev);
+	unsigned long flags;
+
+	if (pm_runtime_status_suspended(dev))
+		pm_runtime_resume(dev);
+
+	if (cdns->roles[cdns->role]->suspend) {
+		spin_lock_irqsave(&cdns->lock, flags);
+		cdns->roles[cdns->role]->suspend(cdns, false);
+		spin_unlock_irqrestore(&cdns->lock, flags);
 	}
 
+	return cdns3_controller_suspend(dev, PMSG_SUSPEND);
+}
+
+static int cdns3_resume(struct device *dev)
+{
+	int ret;
+
+	ret = cdns3_controller_resume(dev, PMSG_RESUME);
+	if (ret)
+		return ret;
+
 	pm_runtime_disable(dev);
 	pm_runtime_set_active(dev);
 	pm_runtime_enable(dev);
 
-	return 0;
+	return ret;
 }
-#endif
+#endif /* CONFIG_PM_SLEEP */
+#endif /* CONFIG_PM */
 
 static const struct dev_pm_ops cdns3_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(cdns3_suspend, cdns3_resume)
+	SET_RUNTIME_PM_OPS(cdns3_runtime_suspend, cdns3_runtime_resume, NULL)
 };
 
 #ifdef CONFIG_OF
diff --git a/drivers/usb/cdns3/core.h b/drivers/usb/cdns3/core.h
index 1ad1f1fe61e9..1b1707796db2 100644
--- a/drivers/usb/cdns3/core.h
+++ b/drivers/usb/cdns3/core.h
@@ -38,6 +38,12 @@ struct cdns3_role_driver {
 };
 
 #define CDNS3_XHCI_RESOURCES_NUM	2
+
+struct cdns3_platform_data {
+	int (*platform_suspend)(struct device *dev,
+			bool suspend, bool wakeup);
+};
+
 /**
  * struct cdns3 - Representation of Cadence USB3 DRD controller.
  * @dev: pointer to Cadence device struct
@@ -50,6 +56,7 @@ struct cdns3_role_driver {
  * @otg_regs: pointer to base of otg registers
  * @otg_irq: irq number for otg controller
  * @dev_irq: irq number for device controller
+ * @wakeup_irq: irq number for wakeup event, it is optional
  * @roles: array of supported roles for this controller
  * @role: current role
  * @host_dev: the child host device pointer for cdns3 core
@@ -62,6 +69,10 @@ struct cdns3_role_driver {
  *           This field based on firmware setting, kernel configuration
  *           and hardware configuration.
  * @role_sw: pointer to role switch object.
+ * @in_lpm: indicate the controller is in low power mode
+ * @wakeup_pending: wakeup interrupt pending
+ * @pdata: platform data from glue layer
+ * @lock: spinlock structure
  */
 struct cdns3 {
 	struct device			*dev;
@@ -79,6 +90,7 @@ struct cdns3 {
 
 	int				otg_irq;
 	int				dev_irq;
+	int				wakeup_irq;
 	struct cdns3_role_driver	*roles[USB_ROLE_DEVICE + 1];
 	enum usb_role			role;
 	struct platform_device		*host_dev;
@@ -89,6 +101,10 @@ struct cdns3 {
 	struct mutex			mutex;
 	enum usb_dr_mode		dr_mode;
 	struct usb_role_switch		*role_sw;
+	bool				in_lpm;
+	bool				wakeup_pending;
+	struct cdns3_platform_data	*pdata;
+	spinlock_t			lock;
 };
 
 int cdns3_hw_role_switch(struct cdns3 *cdns);
diff --git a/drivers/usb/cdns3/drd.c b/drivers/usb/cdns3/drd.c
index 58089841ed52..ac90a484e63c 100644
--- a/drivers/usb/cdns3/drd.c
+++ b/drivers/usb/cdns3/drd.c
@@ -281,6 +281,9 @@ static irqreturn_t cdns3_drd_irq(int irq, void *data)
 	if (cdns->dr_mode != USB_DR_MODE_OTG)
 		return ret;
 
+	if (cdns->in_lpm)
+		return ret;
+
 	reg = readl(&cdns->otg_regs->ivect);
 
 	if (!reg)
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
index 7c2913bc8bd7..0111fba95797 100644
--- a/drivers/usb/cdns3/gadget.c
+++ b/drivers/usb/cdns3/gadget.c
@@ -1766,9 +1766,13 @@ static void cdns3_check_usb_interrupt_proceed(struct cdns3_device *priv_dev,
 static irqreturn_t cdns3_device_irq_handler(int irq, void *data)
 {
 	struct cdns3_device *priv_dev = data;
+	struct cdns3 *cdns = dev_get_drvdata(priv_dev->dev);
 	irqreturn_t ret = IRQ_NONE;
 	u32 reg;
 
+	if (cdns->in_lpm)
+		return ret;
+
 	/* check USB device interrupt */
 	reg = readl(&priv_dev->regs->usb_ists);
 	if (reg) {
diff --git a/drivers/usb/cdns3/host.c b/drivers/usb/cdns3/host.c
index ad788bf3fe4f..b579ef15f4e0 100644
--- a/drivers/usb/cdns3/host.c
+++ b/drivers/usb/cdns3/host.c
@@ -13,11 +13,13 @@
 #include "core.h"
 #include "drd.h"
 #include "host-export.h"
+#include <linux/usb/hcd.h>
 
 static int __cdns3_host_init(struct cdns3 *cdns)
 {
 	struct platform_device *xhci;
 	int ret;
+	struct usb_hcd *hcd;
 
 	cdns3_drd_switch_host(cdns, 1);
 
@@ -43,6 +45,11 @@ static int __cdns3_host_init(struct cdns3 *cdns)
 		goto err1;
 	}
 
+	/* Glue needs to access xHCI region register for Power management */
+	hcd = platform_get_drvdata(xhci);
+	if (hcd)
+		cdns->xhci_regs = hcd->regs;
+
 	return 0;
 err1:
 	platform_device_put(xhci);
-- 
2.17.1

[PATCH v4 3/9] usb: cdns3: imx: add glue layer runtime pm implementation

[Peter Chen]

Add imx glue layer runtime pm implementation, and the runtime
pm is default off.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/cdns3-imx.c | 203 ++++++++++++++++++++++++++++++++--
 1 file changed, 192 insertions(+), 11 deletions(-)

diff --git a/drivers/usb/cdns3/cdns3-imx.c b/drivers/usb/cdns3/cdns3-imx.c
index aba988e71958..b0254ecd9867 100644
--- a/drivers/usb/cdns3/cdns3-imx.c
+++ b/drivers/usb/cdns3/cdns3-imx.c
@@ -15,6 +15,8 @@
 #include <linux/io.h>
 #include <linux/of_platform.h>
 #include <linux/iopoll.h>
+#include <linux/pm_runtime.h>
+#include "core.h"
 
 #define USB3_CORE_CTRL1    0x00
 #define USB3_CORE_CTRL2    0x04
@@ -32,7 +34,7 @@
 /* Register bits definition */
 
 /* USB3_CORE_CTRL1 */
-#define SW_RESET_MASK	(0x3f << 26)
+#define SW_RESET_MASK	GENMASK(31, 26)
 #define PWR_SW_RESET	BIT(31)
 #define APB_SW_RESET	BIT(30)
 #define AXI_SW_RESET	BIT(29)
@@ -44,17 +46,17 @@
 #define OC_DISABLE	BIT(9)
 #define MDCTRL_CLK_SEL	BIT(7)
 #define MODE_STRAP_MASK	(0x7)
-#define DEV_MODE	(1 << 2)
-#define HOST_MODE	(1 << 1)
-#define OTG_MODE	(1 << 0)
+#define DEV_MODE	BIT(2)
+#define HOST_MODE	BIT(1)
+#define OTG_MODE	BIT(0)
 
 /* USB3_INT_REG */
 #define CLK_125_REQ	BIT(29)
 #define LPM_CLK_REQ	BIT(28)
 #define DEVU3_WAEKUP_EN	BIT(14)
 #define OTG_WAKEUP_EN	BIT(12)
-#define DEV_INT_EN (3 << 8) /* DEV INT b9:8 */
-#define HOST_INT1_EN (1 << 0) /* HOST INT b7:0 */
+#define DEV_INT_EN	GENMASK(9, 8) /* DEV INT b9:8 */
+#define HOST_INT1_EN	BIT(0) /* HOST INT b7:0 */
 
 /* USB3_CORE_STATUS */
 #define MDCTRL_CLK_STATUS	BIT(15)
@@ -62,15 +64,34 @@
 #define HOST_POWER_ON_READY	BIT(12)
 
 /* USB3_SSPHY_STATUS */
-#define CLK_VALID_MASK		(0x3f << 26)
-#define CLK_VALID_COMPARE_BITS	(0xf << 28)
-#define PHY_REFCLK_REQ		(1 << 0)
+#define CLK_VALID_MASK		GENMASK(31, 26)
+#define CLK_VALID_COMPARE_BITS	GENMASK(31, 28)
+#define PHY_REFCLK_REQ		BIT(0)
+
+/* OTG registers definition */
+#define OTGSTS		0x4
+/* OTGSTS */
+#define OTG_NRDY	BIT(11)
+
+/* xHCI registers definition  */
+#define XECP_PM_PMCSR		0x8018
+#define XECP_AUX_CTRL_REG1	0x8120
+
+/* Register bits definition */
+/* XECP_AUX_CTRL_REG1 */
+#define CFG_RXDET_P3_EN		BIT(15)
+
+/* XECP_PM_PMCSR */
+#define PS_MASK			GENMASK(1, 0)
+#define PS_D0			0
+#define PS_D1			1
 
 struct cdns_imx {
 	struct device *dev;
 	void __iomem *noncore;
 	struct clk_bulk_data *clks;
 	int num_clks;
+	struct platform_device *cdns3_pdev;
 };
 
 static inline u32 cdns_imx_readl(struct cdns_imx *data, u32 offset)
@@ -126,6 +147,20 @@ static int cdns_imx_noncore_init(struct cdns_imx *data)
 	return ret;
 }
 
+static int cdns_imx_platform_suspend(struct device *dev,
+	bool suspend, bool wakeup);
+static struct cdns3_platform_data cdns_imx_pdata = {
+	.platform_suspend = cdns_imx_platform_suspend,
+};
+
+static struct of_dev_auxdata cdns_imx_auxdata[] = {
+	{
+	.compatible = "cdns,usb3",
+	.platform_data = &cdns_imx_pdata,
+	},
+	{},
+};
+
 static int cdns_imx_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -162,14 +197,18 @@ static int cdns_imx_probe(struct platform_device *pdev)
 	if (ret)
 		goto err;
 
-	ret = of_platform_populate(node, NULL, NULL, dev);
+	ret = of_platform_populate(node, NULL, cdns_imx_auxdata, dev);
 	if (ret) {
 		dev_err(dev, "failed to create children: %d\n", ret);
 		goto err;
 	}
 
-	return ret;
+	device_set_wakeup_capable(dev, true);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_forbid(dev);
 
+	return ret;
 err:
 	clk_bulk_disable_unprepare(data->num_clks, data->clks);
 	return ret;
@@ -194,6 +233,147 @@ static int cdns_imx_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static void cdns3_set_wakeup(struct cdns_imx *data, bool enable)
+{
+	u32 value;
+
+	value = cdns_imx_readl(data, USB3_INT_REG);
+	if (enable)
+		value |= OTG_WAKEUP_EN | DEVU3_WAEKUP_EN;
+	else
+		value &= ~(OTG_WAKEUP_EN | DEVU3_WAEKUP_EN);
+
+	cdns_imx_writel(data, USB3_INT_REG, value);
+}
+
+static int cdns_imx_platform_suspend(struct device *dev,
+		bool suspend, bool wakeup)
+{
+	struct cdns3 *cdns = dev_get_drvdata(dev);
+	struct device *parent = dev->parent;
+	struct cdns_imx *data = dev_get_drvdata(parent);
+	void __iomem *otg_regs = cdns->otg_regs;
+	void __iomem *xhci_regs = cdns->xhci_regs;
+	u32 value;
+	int ret = 0;
+
+	if (cdns->role != USB_ROLE_HOST)
+		return 0;
+
+	if (suspend) {
+		/* SW request low power when all usb ports allow to it ??? */
+		value = readl(xhci_regs + XECP_PM_PMCSR);
+		value &= ~PS_MASK;
+		value |= PS_D1;
+		writel(value, xhci_regs + XECP_PM_PMCSR);
+
+		/* mdctrl_clk_sel */
+		value = cdns_imx_readl(data, USB3_CORE_CTRL1);
+		value |= MDCTRL_CLK_SEL;
+		cdns_imx_writel(data, USB3_CORE_CTRL1, value);
+
+		/* wait for mdctrl_clk_status */
+		value = cdns_imx_readl(data, USB3_CORE_STATUS);
+		ret = readl_poll_timeout(data->noncore + USB3_CORE_STATUS, value,
+			(value & MDCTRL_CLK_STATUS) == MDCTRL_CLK_STATUS,
+			10, 100000);
+		if (ret)
+			dev_warn(parent, "wait mdctrl_clk_status timeout\n");
+
+		/* wait lpm_clk_req to be 0 */
+		value = cdns_imx_readl(data, USB3_INT_REG);
+		ret = readl_poll_timeout(data->noncore + USB3_INT_REG, value,
+			(value & LPM_CLK_REQ) != LPM_CLK_REQ,
+			10, 100000);
+		if (ret)
+			dev_warn(parent, "wait lpm_clk_req timeout\n");
+
+		/* wait phy_refclk_req to be 0 */
+		value = cdns_imx_readl(data, USB3_SSPHY_STATUS);
+		ret = readl_poll_timeout(data->noncore + USB3_SSPHY_STATUS, value,
+			(value & PHY_REFCLK_REQ) != PHY_REFCLK_REQ,
+			10, 100000);
+		if (ret)
+			dev_warn(parent, "wait phy_refclk_req timeout\n");
+
+		cdns3_set_wakeup(data, wakeup);
+	} else {
+		cdns3_set_wakeup(data, false);
+
+		/* SW request D0 */
+		value = readl(xhci_regs + XECP_PM_PMCSR);
+		value &= ~PS_MASK;
+		value |= PS_D0;
+		writel(value, xhci_regs + XECP_PM_PMCSR);
+
+		/* clr CFG_RXDET_P3_EN */
+		value = readl(xhci_regs + XECP_AUX_CTRL_REG1);
+		value &= ~CFG_RXDET_P3_EN;
+		writel(value, xhci_regs + XECP_AUX_CTRL_REG1);
+
+		/* clear mdctrl_clk_sel */
+		value = cdns_imx_readl(data, USB3_CORE_CTRL1);
+		value &= ~MDCTRL_CLK_SEL;
+		cdns_imx_writel(data, USB3_CORE_CTRL1, value);
+
+		/* wait CLK_125_REQ to be 1 */
+		value = cdns_imx_readl(data, USB3_INT_REG);
+		ret = readl_poll_timeout(data->noncore + USB3_INT_REG, value,
+			(value & CLK_125_REQ) == CLK_125_REQ,
+			10, 100000);
+		if (ret)
+			dev_warn(parent, "wait CLK_125_REQ timeout\n");
+
+		/* wait for mdctrl_clk_status is cleared */
+		value = cdns_imx_readl(data, USB3_CORE_STATUS);
+		ret = readl_poll_timeout(data->noncore + USB3_CORE_STATUS, value,
+			(value & MDCTRL_CLK_STATUS) != MDCTRL_CLK_STATUS,
+			10, 100000);
+		if (ret)
+			dev_warn(parent, "wait mdctrl_clk_status cleared timeout\n");
+
+		/* Wait until OTG_NRDY is 0 */
+		value = readl(otg_regs + OTGSTS);
+		ret = readl_poll_timeout(otg_regs + OTGSTS, value,
+			(value & OTG_NRDY) != OTG_NRDY,
+			10, 100000);
+		if (ret)
+			dev_warn(parent, "wait OTG ready timeout\n");
+	}
+
+	return ret;
+
+}
+
+static int cdns_imx_resume(struct device *dev)
+{
+	struct cdns_imx *data = dev_get_drvdata(dev);
+
+	return clk_bulk_prepare_enable(data->num_clks, data->clks);
+}
+
+static int cdns_imx_suspend(struct device *dev)
+{
+	struct cdns_imx *data = dev_get_drvdata(dev);
+
+	clk_bulk_disable_unprepare(data->num_clks, data->clks);
+
+	return 0;
+}
+#else
+static int cdns_imx_platform_suspend(struct device *dev,
+	bool suspend, bool wakeup)
+{
+	return 0;
+}
+
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops cdns_imx_pm_ops = {
+	SET_RUNTIME_PM_OPS(cdns_imx_suspend, cdns_imx_resume, NULL)
+};
+
 static const struct of_device_id cdns_imx_of_match[] = {
 	{ .compatible = "fsl,imx8qm-usb3", },
 	{},
@@ -206,6 +386,7 @@ static struct platform_driver cdns_imx_driver = {
 	.driver		= {
 		.name	= "cdns3-imx",
 		.of_match_table	= cdns_imx_of_match,
+		.pm	= &cdns_imx_pm_ops,
 	},
 };
 module_platform_driver(cdns_imx_driver);
-- 
2.17.1

[PATCH v4 4/9] usb: host: xhci-plat: add platform data support

[Peter Chen]

Some xhci hosts (eg dwc3 and cdns3) do not use OF to create
platform device, they create xhci-plat platform device runtime.
And these platforms may also have quirks, and the quirks could
be supplied by their parent device through platform data.

Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/host/xhci-plat.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index f6b4089bfc4a..38bea2b6a17d 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -264,7 +264,11 @@ static int xhci_plat_probe(struct platform_device *pdev)
 	if (ret)
 		goto disable_reg_clk;
 
-	priv_match = of_device_get_match_data(&pdev->dev);
+	if (pdev->dev.of_node)
+		priv_match = of_device_get_match_data(&pdev->dev);
+	else
+		priv_match = dev_get_platdata(&pdev->dev);
+
 	if (priv_match) {
 		struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd);
 
-- 
2.17.1

[PATCH v4 5/9] usb: host: xhci-plat: add .suspend_quirk for struct xhci_plat_priv

[Peter Chen]

Some platforms (eg cdns3) may have special sequences between
xhci_bus_suspend and xhci_suspend, add .suspend_quick for it.

Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/host/xhci-plat.c | 19 +++++++++++++++++++
 drivers/usb/host/xhci-plat.h |  1 +
 2 files changed, 20 insertions(+)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 38bea2b6a17d..51e20464fe0a 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -54,6 +54,16 @@ static int xhci_priv_init_quirk(struct usb_hcd *hcd)
 	return priv->init_quirk(hcd);
 }
 
+static int xhci_priv_suspend_quirk(struct usb_hcd *hcd)
+{
+	struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd);
+
+	if (!priv->suspend_quirk)
+		return 0;
+
+	return priv->suspend_quirk(hcd);
+}
+
 static int xhci_priv_resume_quirk(struct usb_hcd *hcd)
 {
 	struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd);
@@ -401,7 +411,11 @@ static int __maybe_unused xhci_plat_suspend(struct device *dev)
 {
 	struct usb_hcd	*hcd = dev_get_drvdata(dev);
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
+	int ret;
 
+	ret = xhci_priv_suspend_quirk(hcd);
+	if (ret)
+		return ret;
 	/*
 	 * xhci_suspend() needs `do_wakeup` to know whether host is allowed
 	 * to do wakeup during suspend. Since xhci_plat_suspend is currently
@@ -438,6 +452,11 @@ static int __maybe_unused xhci_plat_runtime_suspend(struct device *dev)
 {
 	struct usb_hcd  *hcd = dev_get_drvdata(dev);
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	int ret;
+
+	ret = xhci_priv_suspend_quirk(hcd);
+	if (ret)
+		return ret;
 
 	return xhci_suspend(xhci, true);
 }
diff --git a/drivers/usb/host/xhci-plat.h b/drivers/usb/host/xhci-plat.h
index b49f6447bd3a..1fb149d1fbce 100644
--- a/drivers/usb/host/xhci-plat.h
+++ b/drivers/usb/host/xhci-plat.h
@@ -15,6 +15,7 @@ struct xhci_plat_priv {
 	unsigned long long quirks;
 	void (*plat_start)(struct usb_hcd *);
 	int (*init_quirk)(struct usb_hcd *);
+	int (*suspend_quirk)(struct usb_hcd *);
 	int (*resume_quirk)(struct usb_hcd *);
 };
 
-- 
2.17.1

[PATCH v4 6/9] usb: host: xhci-plat: delete the unnecessary code

[Peter Chen]

The if {} condition is duplicated with outer if {} condition.

Reviewed-by: Jun Li <jun.li@nxp.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/host/xhci-plat.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 51e20464fe0a..03d6bbe51919 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -283,8 +283,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
 		struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd);
 
 		/* Just copy data for now */
-		if (priv_match)
-			*priv = *priv_match;
+		*priv = *priv_match;
 	}
 
 	device_wakeup_enable(hcd->self.controller);
-- 
2.17.1

[PATCH v4 7/9] usb: host: xhci-plat: add priv quirk for skip PHY initialization

[Peter Chen]

Some DRD controllers (eg, dwc3 & cdns3) have PHY management at
their own driver to cover both device and host mode, so add one
priv quirk for such users to skip PHY management from HCD core.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/host/xhci-plat.c | 8 ++++++--
 drivers/usb/host/xhci.h      | 1 +
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 03d6bbe51919..cebe24ec80a5 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -183,6 +183,8 @@ static int xhci_plat_probe(struct platform_device *pdev)
 	struct usb_hcd		*hcd;
 	int			ret;
 	int			irq;
+	struct xhci_plat_priv	*priv = NULL;
+
 
 	if (usb_disabled())
 		return -ENODEV;
@@ -280,8 +282,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
 		priv_match = dev_get_platdata(&pdev->dev);
 
 	if (priv_match) {
-		struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd);
-
+		priv = hcd_to_xhci_priv(hcd);
 		/* Just copy data for now */
 		*priv = *priv_match;
 	}
@@ -329,6 +330,9 @@ static int xhci_plat_probe(struct platform_device *pdev)
 
 	hcd->tpl_support = of_usb_host_tpl_support(sysdev->of_node);
 	xhci->shared_hcd->tpl_support = hcd->tpl_support;
+	if (priv && (priv->quirks & XHCI_SKIP_PHY_INIT))
+		hcd->skip_phy_initialization = 1;
+
 	ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
 	if (ret)
 		goto disable_usb_phy;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index c295e8a7f5ae..07d71fec18d5 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1874,6 +1874,7 @@ struct xhci_hcd {
 #define XHCI_RESET_PLL_ON_DISCONNECT	BIT_ULL(34)
 #define XHCI_SNPS_BROKEN_SUSPEND    BIT_ULL(35)
 #define XHCI_RENESAS_FW_QUIRK	BIT_ULL(36)
+#define XHCI_SKIP_PHY_INIT	BIT_ULL(37)
 
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;
-- 
2.17.1

[PATCH v4 8/9] usb: cdns3: host: add .suspend_quirk for xhci-plat.c

[Peter Chen]

cdns3 has some special PM sequence between xhci_bus_suspend and
xhci_suspend, add quirk to implement it.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/host-export.h |  6 +++++
 drivers/usb/cdns3/host.c        | 40 +++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/drivers/usb/cdns3/host-export.h b/drivers/usb/cdns3/host-export.h
index ae11810f8826..26041718a086 100644
--- a/drivers/usb/cdns3/host-export.h
+++ b/drivers/usb/cdns3/host-export.h
@@ -9,9 +9,11 @@
 #ifndef __LINUX_CDNS3_HOST_EXPORT
 #define __LINUX_CDNS3_HOST_EXPORT
 
+struct usb_hcd;
 #ifdef CONFIG_USB_CDNS3_HOST
 
 int cdns3_host_init(struct cdns3 *cdns);
+int xhci_cdns3_suspend_quirk(struct usb_hcd *hcd);
 
 #else
 
@@ -21,6 +23,10 @@ static inline int cdns3_host_init(struct cdns3 *cdns)
 }
 
 static inline void cdns3_host_exit(struct cdns3 *cdns) { }
+static inline int xhci_cdns3_suspend_quirk(struct usb_hcd *hcd)
+{
+	return 0;
+}
 
 #endif /* CONFIG_USB_CDNS3_HOST */
 
diff --git a/drivers/usb/cdns3/host.c b/drivers/usb/cdns3/host.c
index b579ef15f4e0..030d6421abd3 100644
--- a/drivers/usb/cdns3/host.c
+++ b/drivers/usb/cdns3/host.c
@@ -14,6 +14,18 @@
 #include "drd.h"
 #include "host-export.h"
 #include <linux/usb/hcd.h>
+#include "../host/xhci.h"
+#include "../host/xhci-plat.h"
+
+#define XECP_PORT_CAP_REG	0x8000
+#define XECP_AUX_CTRL_REG1	0x8120
+
+#define CFG_RXDET_P3_EN		(1 << 15)
+#define LPM_2_STB_SWITCH_EN	(1 << 25)
+
+static const struct xhci_plat_priv xhci_plat_cdns3_xhci = {
+	.suspend_quirk = xhci_cdns3_suspend_quirk,
+};
 
 static int __cdns3_host_init(struct cdns3 *cdns)
 {
@@ -39,6 +51,11 @@ static int __cdns3_host_init(struct cdns3 *cdns)
 		goto err1;
 	}
 
+	ret = platform_device_add_data(xhci, &xhci_plat_cdns3_xhci,
+			sizeof(struct xhci_plat_priv));
+	if (ret)
+		goto err1;
+
 	ret = platform_device_add(xhci);
 	if (ret) {
 		dev_err(cdns->dev, "failed to register xHCI device\n");
@@ -56,6 +73,29 @@ static int __cdns3_host_init(struct cdns3 *cdns)
 	return ret;
 }
 
+int xhci_cdns3_suspend_quirk(struct usb_hcd *hcd)
+{
+	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
+	u32 value;
+
+	/* set usbcmd.EU3S */
+	value = readl(&xhci->op_regs->command);
+	value |= CMD_PM_INDEX;
+	writel(value, &xhci->op_regs->command);
+
+	if (hcd->regs) {
+		value = readl(hcd->regs + XECP_AUX_CTRL_REG1);
+		value |= CFG_RXDET_P3_EN;
+		writel(value, hcd->regs + XECP_AUX_CTRL_REG1);
+
+		value = readl(hcd->regs + XECP_PORT_CAP_REG);
+		value |= LPM_2_STB_SWITCH_EN;
+		writel(value, hcd->regs + XECP_PORT_CAP_REG);
+	}
+
+	return 0;
+}
+
 static void cdns3_host_exit(struct cdns3 *cdns)
 {
 	platform_device_unregister(cdns->host_dev);
-- 
2.17.1

[PATCH v4 9/9] usb: cdns3: host: add xhci_plat_priv quirk XHCI_SKIP_PHY_INIT

[Peter Chen]

cdns3 manages PHY by own DRD driver, so skip the management by
HCD core.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/host.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/cdns3/host.c b/drivers/usb/cdns3/host.c
index 030d6421abd3..1dfbe23fa089 100644
--- a/drivers/usb/cdns3/host.c
+++ b/drivers/usb/cdns3/host.c
@@ -24,6 +24,7 @@
 #define LPM_2_STB_SWITCH_EN	(1 << 25)
 
 static const struct xhci_plat_priv xhci_plat_cdns3_xhci = {
+	.quirks = XHCI_SKIP_PHY_INIT,
 	.suspend_quirk = xhci_cdns3_suspend_quirk,
 };
 
-- 
2.17.1

Re: [PATCH v4 1/9] usb: cdns3: introduce cdns3_set_phy_power API

[Greg KH]

On Fri, Jul 03, 2020 at 02:26:45PM +0800, Peter Chen wrote:
> Since we have both USB2 and USB3 PHYs for cdns3 controller, it is
> better we have a unity API to handle both USB2 and USB3's power, it
> could simplify code for error handling and further power management
> implementation.
> 
> Reviewed-by: Jun Li <jun.li@nxp.com>
> Signed-off-by: Peter Chen <peter.chen@nxp.com>
> ---
>  drivers/usb/cdns3/core.c | 44 ++++++++++++++++++++++++++--------------
>  1 file changed, 29 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
> index 19bbb5b7e6b6..bfd09aa98c12 100644
> --- a/drivers/usb/cdns3/core.c
> +++ b/drivers/usb/cdns3/core.c
> @@ -384,6 +384,28 @@ static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role)
>  	return ret;
>  }
>  
> +static int cdns3_set_phy_power(struct cdns3 *cdns, bool on)

Please just make function calls self-describing, instead of having to
try to remember what a specific flag means.  This isn't as bad as some
functions, but the general idea remains, this should be 2 functions:
	set_phy_power_off()
	set_phy_power_on()

no need for the cdns3_ prefix, it's a static function.

Then have those two functions call a helper if you really want to, but
that means that reading where those functions are called is obvious and
no need to backtrack to where this was declared to determine that the
second parameter meant on/off and not is_disabled/not_disabled or
something crazy like that.



> +{
> +	int ret = 0;
> +
> +	if (on) {
> +		ret = phy_power_on(cdns->usb2_phy);

See, phy gets it right.

> +		if (ret)
> +			return ret;
> +
> +		ret = phy_power_on(cdns->usb3_phy);
> +		if (ret) {
> +			phy_power_off(cdns->usb2_phy);
> +			return ret;
> +		}
> +	} else {
> +		phy_power_off(cdns->usb3_phy);
> +		phy_power_off(cdns->usb2_phy);

Ick, even worse, this needs to be 2 separate functions as there is NO
common code path here at all.

thanks,

greg k-h

Re: [PATCH v4 1/9] usb: cdns3: introduce cdns3_set_phy_power API

[Peter Chen]

On 20-07-03 09:00:44, Greg KH wrote:
> On Fri, Jul 03, 2020 at 02:26:45PM +0800, Peter Chen wrote:
> > Since we have both USB2 and USB3 PHYs for cdns3 controller, it is
> > better we have a unity API to handle both USB2 and USB3's power, it
> > could simplify code for error handling and further power management
> > implementation.
> > 
> > Reviewed-by: Jun Li <jun.li@nxp.com>
> > Signed-off-by: Peter Chen <peter.chen@nxp.com>
> > ---
> >  drivers/usb/cdns3/core.c | 44 ++++++++++++++++++++++++++--------------
> >  1 file changed, 29 insertions(+), 15 deletions(-)
> > 
> > diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
> > index 19bbb5b7e6b6..bfd09aa98c12 100644
> > --- a/drivers/usb/cdns3/core.c
> > +++ b/drivers/usb/cdns3/core.c
> > @@ -384,6 +384,28 @@ static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role)
> >  	return ret;
> >  }
> >  
> > +static int cdns3_set_phy_power(struct cdns3 *cdns, bool on)
> 
> Please just make function calls self-describing, instead of having to
> try to remember what a specific flag means.  This isn't as bad as some
> functions, but the general idea remains, this should be 2 functions:
> 	set_phy_power_off()
> 	set_phy_power_on()
> 
> no need for the cdns3_ prefix, it's a static function.
> 
> Then have those two functions call a helper if you really want to, but
> that means that reading where those functions are called is obvious and
> no need to backtrack to where this was declared to determine that the
> second parameter meant on/off and not is_disabled/not_disabled or
> something crazy like that.
> 
> 
> 
> > +{
> > +	int ret = 0;
> > +
> > +	if (on) {
> > +		ret = phy_power_on(cdns->usb2_phy);
> 
> See, phy gets it right.
> 
> > +		if (ret)
> > +			return ret;
> > +
> > +		ret = phy_power_on(cdns->usb3_phy);
> > +		if (ret) {
> > +			phy_power_off(cdns->usb2_phy);
> > +			return ret;
> > +		}
> > +	} else {
> > +		phy_power_off(cdns->usb3_phy);
> > +		phy_power_off(cdns->usb2_phy);
> 
> Ick, even worse, this needs to be 2 separate functions as there is NO
> common code path here at all.
> 

The purpose of this API is adding two PHY (USB2 and USB3) APIs into one
private APIs since two PHYs power operation are always called together
and we will have more than one places to call them.

If you think it is not necessary, and make code not easy to read, I
could skip this patch.

-- 

Thanks,
Peter Chen

Re: [PATCH v4 1/9] usb: cdns3: introduce cdns3_set_phy_power API

[Greg KH]

On Fri, Jul 03, 2020 at 07:16:19AM +0000, Peter Chen wrote:
> On 20-07-03 09:00:44, Greg KH wrote:
> > On Fri, Jul 03, 2020 at 02:26:45PM +0800, Peter Chen wrote:
> > > Since we have both USB2 and USB3 PHYs for cdns3 controller, it is
> > > better we have a unity API to handle both USB2 and USB3's power, it
> > > could simplify code for error handling and further power management
> > > implementation.
> > > 
> > > Reviewed-by: Jun Li <jun.li@nxp.com>
> > > Signed-off-by: Peter Chen <peter.chen@nxp.com>
> > > ---
> > >  drivers/usb/cdns3/core.c | 44 ++++++++++++++++++++++++++--------------
> > >  1 file changed, 29 insertions(+), 15 deletions(-)
> > > 
> > > diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
> > > index 19bbb5b7e6b6..bfd09aa98c12 100644
> > > --- a/drivers/usb/cdns3/core.c
> > > +++ b/drivers/usb/cdns3/core.c
> > > @@ -384,6 +384,28 @@ static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role)
> > >  	return ret;
> > >  }
> > >  
> > > +static int cdns3_set_phy_power(struct cdns3 *cdns, bool on)
> > 
> > Please just make function calls self-describing, instead of having to
> > try to remember what a specific flag means.  This isn't as bad as some
> > functions, but the general idea remains, this should be 2 functions:
> > 	set_phy_power_off()
> > 	set_phy_power_on()
> > 
> > no need for the cdns3_ prefix, it's a static function.
> > 
> > Then have those two functions call a helper if you really want to, but
> > that means that reading where those functions are called is obvious and
> > no need to backtrack to where this was declared to determine that the
> > second parameter meant on/off and not is_disabled/not_disabled or
> > something crazy like that.
> > 
> > 
> > 
> > > +{
> > > +	int ret = 0;
> > > +
> > > +	if (on) {
> > > +		ret = phy_power_on(cdns->usb2_phy);
> > 
> > See, phy gets it right.
> > 
> > > +		if (ret)
> > > +			return ret;
> > > +
> > > +		ret = phy_power_on(cdns->usb3_phy);
> > > +		if (ret) {
> > > +			phy_power_off(cdns->usb2_phy);
> > > +			return ret;
> > > +		}
> > > +	} else {
> > > +		phy_power_off(cdns->usb3_phy);
> > > +		phy_power_off(cdns->usb2_phy);
> > 
> > Ick, even worse, this needs to be 2 separate functions as there is NO
> > common code path here at all.
> > 
> 
> The purpose of this API is adding two PHY (USB2 and USB3) APIs into one
> private APIs since two PHYs power operation are always called together
> and we will have more than one places to call them.

That's fine, just make 2 separate functions that do this, don't combine
it into one that does two totally separate code paths based on a flag
that is passed into it.

thanks,

greg k-h

Re: [PATCH v4 1/9] usb: cdns3: introduce cdns3_set_phy_power API

[Peter Chen]

On 20-07-03 09:23:36, Greg KH wrote:
> On Fri, Jul 03, 2020 at 07:16:19AM +0000, Peter Chen wrote:
> > On 20-07-03 09:00:44, Greg KH wrote:
> > > On Fri, Jul 03, 2020 at 02:26:45PM +0800, Peter Chen wrote:
> > > > Since we have both USB2 and USB3 PHYs for cdns3 controller, it is
> > > > better we have a unity API to handle both USB2 and USB3's power, it
> > > > could simplify code for error handling and further power management
> > > > implementation.
> > > > 
> > > > Reviewed-by: Jun Li <jun.li@nxp.com>
> > > > Signed-off-by: Peter Chen <peter.chen@nxp.com>
> > > > ---
> > > >  drivers/usb/cdns3/core.c | 44 ++++++++++++++++++++++++++--------------
> > > >  1 file changed, 29 insertions(+), 15 deletions(-)
> > > > 
> > > > diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
> > > > index 19bbb5b7e6b6..bfd09aa98c12 100644
> > > > --- a/drivers/usb/cdns3/core.c
> > > > +++ b/drivers/usb/cdns3/core.c
> > > > @@ -384,6 +384,28 @@ static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role)
> > > >  	return ret;
> > > >  }
> > > >  
> > > > +static int cdns3_set_phy_power(struct cdns3 *cdns, bool on)
> > > 
> > > Please just make function calls self-describing, instead of having to
> > > try to remember what a specific flag means.  This isn't as bad as some
> > > functions, but the general idea remains, this should be 2 functions:
> > > 	set_phy_power_off()
> > > 	set_phy_power_on()
> > > 
> > > no need for the cdns3_ prefix, it's a static function.
> > > 
> > > Then have those two functions call a helper if you really want to, but
> > > that means that reading where those functions are called is obvious and
> > > no need to backtrack to where this was declared to determine that the
> > > second parameter meant on/off and not is_disabled/not_disabled or
> > > something crazy like that.
> > > 
> > > 
> > > 
> > > > +{
> > > > +	int ret = 0;
> > > > +
> > > > +	if (on) {
> > > > +		ret = phy_power_on(cdns->usb2_phy);
> > > 
> > > See, phy gets it right.
> > > 
> > > > +		if (ret)
> > > > +			return ret;
> > > > +
> > > > +		ret = phy_power_on(cdns->usb3_phy);
> > > > +		if (ret) {
> > > > +			phy_power_off(cdns->usb2_phy);
> > > > +			return ret;
> > > > +		}
> > > > +	} else {
> > > > +		phy_power_off(cdns->usb3_phy);
> > > > +		phy_power_off(cdns->usb2_phy);
> > > 
> > > Ick, even worse, this needs to be 2 separate functions as there is NO
> > > common code path here at all.
> > > 
> > 
> > The purpose of this API is adding two PHY (USB2 and USB3) APIs into one
> > private APIs since two PHYs power operation are always called together
> > and we will have more than one places to call them.
> 
> That's fine, just make 2 separate functions that do this, don't combine
> it into one that does two totally separate code paths based on a flag
> that is passed into it.
> 

Thanks, will change.

-- 

Thanks,
Peter Chen

Re: [PATCH v4 3/9] usb: cdns3: imx: add glue layer runtime pm implementation

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 11755 bytes --]

Hi Peter,

I love your patch! Perhaps something to improve:

[auto build test WARNING on usb/usb-testing]
[also build test WARNING on balbi-usb/testing/next shawnguo/for-next v5.8-rc3 next-20200703]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use  as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Peter-Chen/usb-some-PM-changes-for-cdns3-and-xhci-plat/20200703-143054
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
config: ia64-randconfig-s031-20200705 (attached as .config)
compiler: ia64-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # apt-get install sparse
        # sparse version: v0.6.2-3-gfa153962-dirty
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=ia64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>


sparse warnings: (new ones prefixed by >>)

>> drivers/usb/cdns3/cdns3-imx.c:256:38: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected void [noderef] __iomem *otg_regs @@     got struct cdns3_otg_common_regs *otg_regs @@
>> drivers/usb/cdns3/cdns3-imx.c:256:38: sparse:     expected void [noderef] __iomem *otg_regs
>> drivers/usb/cdns3/cdns3-imx.c:256:38: sparse:     got struct cdns3_otg_common_regs *otg_regs
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:225:22: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned int [usertype] value @@     got restricted __le32 [usertype] @@
   include/asm-generic/io.h:225:22: sparse:     expected unsigned int [usertype] value
   include/asm-generic/io.h:225:22: sparse:     got restricted __le32 [usertype]
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32

vim +256 drivers/usb/cdns3/cdns3-imx.c

   249	
   250	static int cdns_imx_platform_suspend(struct device *dev,
   251			bool suspend, bool wakeup)
   252	{
   253		struct cdns3 *cdns = dev_get_drvdata(dev);
   254		struct device *parent = dev->parent;
   255		struct cdns_imx *data = dev_get_drvdata(parent);
 > 256		void __iomem *otg_regs = cdns->otg_regs;
   257		void __iomem *xhci_regs = cdns->xhci_regs;
   258		u32 value;
   259		int ret = 0;
   260	
   261		if (cdns->role != USB_ROLE_HOST)
   262			return 0;
   263	
   264		if (suspend) {
   265			/* SW request low power when all usb ports allow to it ??? */
   266			value = readl(xhci_regs + XECP_PM_PMCSR);
   267			value &= ~PS_MASK;
   268			value |= PS_D1;
   269			writel(value, xhci_regs + XECP_PM_PMCSR);
   270	
   271			/* mdctrl_clk_sel */
   272			value = cdns_imx_readl(data, USB3_CORE_CTRL1);
   273			value |= MDCTRL_CLK_SEL;
   274			cdns_imx_writel(data, USB3_CORE_CTRL1, value);
   275	
   276			/* wait for mdctrl_clk_status */
   277			value = cdns_imx_readl(data, USB3_CORE_STATUS);
   278			ret = readl_poll_timeout(data->noncore + USB3_CORE_STATUS, value,
   279				(value & MDCTRL_CLK_STATUS) == MDCTRL_CLK_STATUS,
   280				10, 100000);
   281			if (ret)
   282				dev_warn(parent, "wait mdctrl_clk_status timeout\n");
   283	
   284			/* wait lpm_clk_req to be 0 */
   285			value = cdns_imx_readl(data, USB3_INT_REG);
   286			ret = readl_poll_timeout(data->noncore + USB3_INT_REG, value,
   287				(value & LPM_CLK_REQ) != LPM_CLK_REQ,
   288				10, 100000);
   289			if (ret)
   290				dev_warn(parent, "wait lpm_clk_req timeout\n");
   291	
   292			/* wait phy_refclk_req to be 0 */
   293			value = cdns_imx_readl(data, USB3_SSPHY_STATUS);
   294			ret = readl_poll_timeout(data->noncore + USB3_SSPHY_STATUS, value,
   295				(value & PHY_REFCLK_REQ) != PHY_REFCLK_REQ,
   296				10, 100000);
   297			if (ret)
   298				dev_warn(parent, "wait phy_refclk_req timeout\n");
   299	
   300			cdns3_set_wakeup(data, wakeup);
   301		} else {
   302			cdns3_set_wakeup(data, false);
   303	
   304			/* SW request D0 */
   305			value = readl(xhci_regs + XECP_PM_PMCSR);
   306			value &= ~PS_MASK;
   307			value |= PS_D0;
   308			writel(value, xhci_regs + XECP_PM_PMCSR);
   309	
   310			/* clr CFG_RXDET_P3_EN */
   311			value = readl(xhci_regs + XECP_AUX_CTRL_REG1);
   312			value &= ~CFG_RXDET_P3_EN;
   313			writel(value, xhci_regs + XECP_AUX_CTRL_REG1);
   314	
   315			/* clear mdctrl_clk_sel */
   316			value = cdns_imx_readl(data, USB3_CORE_CTRL1);
   317			value &= ~MDCTRL_CLK_SEL;
   318			cdns_imx_writel(data, USB3_CORE_CTRL1, value);
   319	
   320			/* wait CLK_125_REQ to be 1 */
   321			value = cdns_imx_readl(data, USB3_INT_REG);
   322			ret = readl_poll_timeout(data->noncore + USB3_INT_REG, value,
   323				(value & CLK_125_REQ) == CLK_125_REQ,
   324				10, 100000);
   325			if (ret)
   326				dev_warn(parent, "wait CLK_125_REQ timeout\n");
   327	
   328			/* wait for mdctrl_clk_status is cleared */
   329			value = cdns_imx_readl(data, USB3_CORE_STATUS);
   330			ret = readl_poll_timeout(data->noncore + USB3_CORE_STATUS, value,
   331				(value & MDCTRL_CLK_STATUS) != MDCTRL_CLK_STATUS,
   332				10, 100000);
   333			if (ret)
   334				dev_warn(parent, "wait mdctrl_clk_status cleared timeout\n");
   335	
   336			/* Wait until OTG_NRDY is 0 */
   337			value = readl(otg_regs + OTGSTS);
   338			ret = readl_poll_timeout(otg_regs + OTGSTS, value,
   339				(value & OTG_NRDY) != OTG_NRDY,
   340				10, 100000);
   341			if (ret)
   342				dev_warn(parent, "wait OTG ready timeout\n");
   343		}
   344	
   345		return ret;
   346	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 31307 bytes --]

Re: [PATCH v4 1/9] usb: cdns3: introduce cdns3_set_phy_power API

[Felipe Balbi]

[-- Attachment #1: Type: text/plain, Size: 1488 bytes --]

Greg KH <gregkh@linuxfoundation.org> writes:

> On Fri, Jul 03, 2020 at 02:26:45PM +0800, Peter Chen wrote:
>> Since we have both USB2 and USB3 PHYs for cdns3 controller, it is
>> better we have a unity API to handle both USB2 and USB3's power, it
>> could simplify code for error handling and further power management
>> implementation.
>> 
>> Reviewed-by: Jun Li <jun.li@nxp.com>
>> Signed-off-by: Peter Chen <peter.chen@nxp.com>
>> ---
>>  drivers/usb/cdns3/core.c | 44 ++++++++++++++++++++++++++--------------
>>  1 file changed, 29 insertions(+), 15 deletions(-)
>> 
>> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
>> index 19bbb5b7e6b6..bfd09aa98c12 100644
>> --- a/drivers/usb/cdns3/core.c
>> +++ b/drivers/usb/cdns3/core.c
>> @@ -384,6 +384,28 @@ static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role)
>>  	return ret;
>>  }
>>  
>> +static int cdns3_set_phy_power(struct cdns3 *cdns, bool on)
>
> Please just make function calls self-describing, instead of having to
> try to remember what a specific flag means.  This isn't as bad as some
> functions, but the general idea remains, this should be 2 functions:
> 	set_phy_power_off()
> 	set_phy_power_on()
>
> no need for the cdns3_ prefix, it's a static function.

the cdns3_ prefix helps when using function trace or function graph
trace. It's a lot easier to say "trace anything matching cdns3_*" than
it is to remember each function ;-)

-- 
balbi

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