USB: EHCI: remove PORT_RWC_BITS when clearing USB_PORT_FEAT_ENABLE

In the ClearPortFeature/USB_PORT_FEAT_ENABLE case, ehci_hub_control()
would read from status_reg, clear PORT_PE, and write the result back to
status_reg. This would clear any bits in PORT_RWC_BITS that were set in
the registers. Fix this by masking these bits off before the write.

Since this masking is common across all ClearPortFeature cases, move it
into a single early location to avoid duplicating it.

Remove the same bugfix from ehci-tegra.c's tegra_ehci_hub_control(), now
that this case is correctly handled by the core.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 8f57c6e..1e332ac 100644 (file)
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -704,6 +704,7 @@ static int ehci_hub_control (
                        goto error;
                wIndex--;
                temp = ehci_readl(ehci, status_reg);
+               temp &= ~PORT_RWC_BITS;
 
                /*
                 * Even if OWNER is set, so the port is owned by the
@@ -717,8 +718,7 @@ static int ehci_hub_control (
                        ehci_writel(ehci, temp & ~PORT_PE, status_reg);
                        break;
                case USB_PORT_FEAT_C_ENABLE:
-                       ehci_writel(ehci, (temp & ~PORT_RWC_BITS) | PORT_PEC,
-                                       status_reg);
+                       ehci_writel(ehci, temp | PORT_PEC, status_reg);
                        break;
                case USB_PORT_FEAT_SUSPEND:
                        if (temp & PORT_RESET)
@@ -747,7 +747,7 @@ static int ehci_hub_control (
                                spin_lock_irqsave(&ehci->lock, flags);
                        }
                        /* resume signaling for 20 msec */
-                       temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
+                       temp &= ~PORT_WAKE_BITS;
                        ehci_writel(ehci, temp | PORT_RESUME, status_reg);
                        ehci->reset_done[wIndex] = jiffies
                                        + msecs_to_jiffies(20);
@@ -757,9 +757,8 @@ static int ehci_hub_control (
                        break;
                case USB_PORT_FEAT_POWER:
                        if (HCS_PPC (ehci->hcs_params))
-                               ehci_writel(ehci,
-                                         temp & ~(PORT_RWC_BITS | PORT_POWER),
-                                         status_reg);
+                               ehci_writel(ehci, temp & ~PORT_POWER,
+                                               status_reg);
                        break;
                case USB_PORT_FEAT_C_CONNECTION:
                        if (ehci->has_lpm) {
@@ -767,12 +766,10 @@ static int ehci_hub_control (
                                temp &= ~PORT_LPM;
                                temp &= ~PORT_DEV_ADDR;
                        }
-                       ehci_writel(ehci, (temp & ~PORT_RWC_BITS) | PORT_CSC,
-                                       status_reg);
+                       ehci_writel(ehci, temp | PORT_CSC, status_reg);
                        break;
                case USB_PORT_FEAT_C_OVER_CURRENT:
-                       ehci_writel(ehci, (temp & ~PORT_RWC_BITS) | PORT_OCC,
-                                       status_reg);
+                       ehci_writel(ehci, temp | PORT_OCC, status_reg);
                        break;
                case USB_PORT_FEAT_C_RESET:
                        /* GetPortStatus clears reset */

diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index 4c8bef6..9f81768 100644 (file)
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -148,18 +148,7 @@ static int tegra_ehci_hub_control(
 
        spin_lock_irqsave(&ehci->lock, flags);
 
-       /*
-        * In ehci_hub_control() for USB_PORT_FEAT_ENABLE clears the other bits
-        * that are write on clear, by writing back the register read value, so
-        * USB_PORT_FEAT_ENABLE is handled by masking the set on clear bits
-        */
-       if (typeReq == ClearPortFeature && wValue == USB_PORT_FEAT_ENABLE) {
-               temp = ehci_readl(ehci, status_reg) & ~PORT_RWC_BITS;
-               ehci_writel(ehci, temp & ~PORT_PE, status_reg);
-               goto done;
-       }
-
-       else if (typeReq == GetPortStatus) {
+       if (typeReq == GetPortStatus) {
                temp = ehci_readl(ehci, status_reg);
                if (tegra->port_resuming && !(temp & PORT_SUSPEND)) {
                        /* Resume completed, re-enable disconnect detection */