[PATCH v2 0/2] Support EHCI reset after resume quirk

[PATCH v2 0/2] Support EHCI reset after resume quirk

[Wu Liang feng]

[PATCH v2 1/2]: Add an optional property "needs-reset-on-resume"
		in usb-ehci dt-bingdings.
[PATCH v2 2/2]: modify ehci-platform driver to support ehci reset
		after resume quirk if necessary.

Wu Liang feng (2):
  dt-bindings: usb-ehci: Add an optional property
	       "needs-reset-on-resume"
  USB: ehci-platform: Support ehci reset after resume quirk

tested on rk3288-pinky

 Documentation/devicetree/bindings/usb/usb-ehci.txt | 1 +
 drivers/usb/host/ehci-hcd.c                        | 6 +++---
 drivers/usb/host/ehci-platform.c                   | 6 +++++-
 drivers/usb/host/ehci.h                            | 2 +-
 include/linux/usb/ehci_pdriver.h                   | 3 +++
 5 files changed, 13 insertions(+), 5 deletions(-)

-- 
1.8.3.2

[PATCH 1/2] dt-bindings: usb-ehci: Add an optional property "needs-reset-on-resume"

[Wu Liang feng]

Add device-tree bindings for EHCI so we can use "needs-reset-on-resume"
property to force EHCI reset after resume if necessary. This is necessary
on platforms like rk3288 that need a reset after resume to detect if a
device has been disconnected during suspend time.

Signed-off-by: Wu Liang feng <wulf@rock-chips.com>
Reviewed-by: Julius Werner <jwerner@google.com>
Reviewed-by: Doug Anderson <dianders@google.com>
Reviewed-by: Tomasz Figa <tfiga@google.com>
Reviewed-by: Pawel Osciak <posciak@google.com>
Reviewed-by: Sonny Rao <sonnyrao@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Doug Anderson <dianders@google.com>
---
 Documentation/devicetree/bindings/usb/usb-ehci.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/usb/usb-ehci.txt b/Documentation/devicetree/bindings/usb/usb-ehci.txt
index 43c1a4e..0b04fdf 100644
--- a/Documentation/devicetree/bindings/usb/usb-ehci.txt
+++ b/Documentation/devicetree/bindings/usb/usb-ehci.txt
@@ -12,6 +12,7 @@ Optional properties:
  - big-endian-regs : boolean, set this for hcds with big-endian registers
  - big-endian-desc : boolean, set this for hcds with big-endian descriptors
  - big-endian : boolean, for hcds with big-endian-regs + big-endian-desc
+ - needs-reset-on-resume : boolean, set this to force EHCI reset after resume
  - clocks : a list of phandle + clock specifier pairs
  - phys : phandle + phy specifier pair
  - phy-names : "usb"
-- 
1.8.3.2

[PATCH 2/2] USB: ehci-platform: Support ehci reset after resume quirk

[Wu Liang feng]

The Rockchip rk3288 EHCI controller doesn't properly detect
the case when a device is removed during suspend. Specifically,
when usb resume from suspend, the EHCI controller maintaining
the USB state (FLAG_CF is 1, Current Connect Status is 1),
but a USB device (like a USB camera on rk3288) may have been
disconnected actually.

Let's add a quirk to force ehci to go into the
usb_root_hub_lost_power() path and reset after resume.
This should generally reset the whole controller and all
ports and initialize everything cleanly again, and bring
the devices back up.

As part of this, rename the "hibernation" paramter of
ehci_resume() to force_reset since hibernation is simply
another case where we can't trust the autodetected status
and need to force a reset of devices.

Signed-off-by: Wu Liang feng <wulf@rock-chips.com>
Reviewed-by: Julius Werner <jwerner@google.com>
Reviewed-by: Doug Anderson <dianders@google.com>
Reviewed-by: Tomasz Figa <tfiga@google.com>
Reviewed-by: Pawel Osciak <posciak@google.com>
Reviewed-by: Sonny Rao <sonnyrao@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Doug Anderson <dianders@google.com>
---
 drivers/usb/host/ehci-hcd.c      | 6 +++---
 drivers/usb/host/ehci-platform.c | 6 +++++-
 drivers/usb/host/ehci.h          | 2 +-
 include/linux/usb/ehci_pdriver.h | 3 +++
 4 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 38bfeed..85e56d1 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -1110,7 +1110,7 @@ int ehci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 EXPORT_SYMBOL_GPL(ehci_suspend);
 
 /* Returns 0 if power was preserved, 1 if power was lost */
-int ehci_resume(struct usb_hcd *hcd, bool hibernated)
+int ehci_resume(struct usb_hcd *hcd, bool force_reset)
 {
 	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
 
@@ -1124,12 +1124,12 @@ int ehci_resume(struct usb_hcd *hcd, bool hibernated)
 		return 0;		/* Controller is dead */
 
 	/*
-	 * If CF is still set and we aren't resuming from hibernation
+	 * If CF is still set and reset isn't forced
 	 * then we maintained suspend power.
 	 * Just undo the effect of ehci_suspend().
 	 */
 	if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF &&
-			!hibernated) {
+			!force_reset) {
 		int	mask = INTR_MASK;
 
 		ehci_prepare_ports_for_controller_resume(ehci);
diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c
index 8557803..db5c29e 100644
--- a/drivers/usb/host/ehci-platform.c
+++ b/drivers/usb/host/ehci-platform.c
@@ -185,6 +185,10 @@ static int ehci_platform_probe(struct platform_device *dev)
 		if (of_property_read_bool(dev->dev.of_node, "big-endian"))
 			ehci->big_endian_mmio = ehci->big_endian_desc = 1;
 
+		if (of_property_read_bool(dev->dev.of_node,
+					  "needs-reset-on-resume"))
+			pdata->reset_on_resume = 1;
+
 		priv->phy = devm_phy_get(&dev->dev, "usb");
 		if (IS_ERR(priv->phy)) {
 			err = PTR_ERR(priv->phy);
@@ -340,7 +344,7 @@ static int ehci_platform_resume(struct device *dev)
 			return err;
 	}
 
-	ehci_resume(hcd, false);
+	ehci_resume(hcd, pdata->reset_on_resume);
 	return 0;
 }
 #endif /* CONFIG_PM_SLEEP */
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 6f0577b..52ef084 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -871,7 +871,7 @@ extern int	ehci_handshake(struct ehci_hcd *ehci, void __iomem *ptr,
 
 #ifdef CONFIG_PM
 extern int	ehci_suspend(struct usb_hcd *hcd, bool do_wakeup);
-extern int	ehci_resume(struct usb_hcd *hcd, bool hibernated);
+extern int	ehci_resume(struct usb_hcd *hcd, bool force_reset);
 #endif	/* CONFIG_PM */
 
 extern int	ehci_hub_control(struct usb_hcd	*hcd, u16 typeReq, u16 wValue,
diff --git a/include/linux/usb/ehci_pdriver.h b/include/linux/usb/ehci_pdriver.h
index 7eb4dcd..6287b39 100644
--- a/include/linux/usb/ehci_pdriver.h
+++ b/include/linux/usb/ehci_pdriver.h
@@ -34,6 +34,8 @@ struct usb_hcd;
  *			after initialization.
  * @no_io_watchdog:	set to 1 if the controller does not need the I/O
  *			watchdog to run.
+ * @reset_on_resume:	set to 1 if the controller needs to be reset after
+ * 			a suspend / resume cycle (but can't detect that itself).
  *
  * These are general configuration options for the EHCI controller. All of
  * these options are activating more or less workarounds for some hardware.
@@ -45,6 +47,7 @@ struct usb_ehci_pdata {
 	unsigned	big_endian_desc:1;
 	unsigned	big_endian_mmio:1;
 	unsigned	no_io_watchdog:1;
+	unsigned	reset_on_resume:1;
 
 	/* Turn on all power and clocks */
 	int (*power_on)(struct platform_device *pdev);
-- 
1.8.3.2

Re: [PATCH 1/2] dt-bindings: usb-ehci: Add an optional property "needs-reset-on-resume"

[Doug Anderson]

Wu Liang feng,

On Mon, Dec 22, 2014 at 2:36 AM, Wu Liang feng <wulf@rock-chips.com> wrote:
> Add device-tree bindings for EHCI so we can use "needs-reset-on-resume"
> property to force EHCI reset after resume if necessary. This is necessary
> on platforms like rk3288 that need a reset after resume to detect if a
> device has been disconnected during suspend time.
>
> Signed-off-by: Wu Liang feng <wulf@rock-chips.com>
> ---
>  Documentation/devicetree/bindings/usb/usb-ehci.txt | 1 +
>  1 file changed, 1 insertion(+)

It may not count for much given my lack of experience with the USB
subsystem, but I'll give it anyway:

Reviewed-by: Doug Anderson <dianders@chromium.org>

-Doug

[PATCH 1/2] dt-bindings: usb-ehci: Add an optional property "needs-reset-on-resume"

[Wu Liang feng]

Add device-tree bindings for EHCI so we can use "needs-reset-on-resume"
property to force EHCI reset after resume if necessary. This is necessary
on platforms like rk3288 that need a reset after resume to detect if a
device has been disconnected during suspend time.

Signed-off-by: Wu Liang feng <wulf@rock-chips.com>
---
 Documentation/devicetree/bindings/usb/usb-ehci.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/usb/usb-ehci.txt b/Documentation/devicetree/bindings/usb/usb-ehci.txt
index 43c1a4e..0b04fdf 100644
--- a/Documentation/devicetree/bindings/usb/usb-ehci.txt
+++ b/Documentation/devicetree/bindings/usb/usb-ehci.txt
@@ -12,6 +12,7 @@ Optional properties:
  - big-endian-regs : boolean, set this for hcds with big-endian registers
  - big-endian-desc : boolean, set this for hcds with big-endian descriptors
  - big-endian : boolean, for hcds with big-endian-regs + big-endian-desc
+ - needs-reset-on-resume : boolean, set this to force EHCI reset after resume
  - clocks : a list of phandle + clock specifier pairs
  - phys : phandle + phy specifier pair
  - phy-names : "usb"
-- 
1.8.3.2