MLK-9618-3 usb: chipidea: host: add port reset for USB OTG HNP

This patch adds host port reset implementation for HNP timing requirement,
which will be called when B host starts enumuration.

Signed-off-by: Li Jun <b47624@freescale.com>
(cherry picked from commit 5a63aca9c698a2eca09473c675ad2c40a62a27d1)

diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index e244e9b..8d92d9b 100644 (file)
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -149,6 +149,38 @@ static int ci_imx_ehci_bus_resume(struct usb_hcd *hcd)
        return 0;
 }
 
+#ifdef CONFIG_USB_OTG
+
+static int ci_start_port_reset(struct usb_hcd *hcd, unsigned port)
+{
+       struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+       u32 __iomem *reg;
+       u32 status;
+
+       if (!port)
+               return -EINVAL;
+       port--;
+       /* start port reset before HNP protocol time out */
+       reg = &ehci->regs->port_status[port];
+       status = ehci_readl(ehci, reg);
+       if (!(status & PORT_CONNECT))
+               return -ENODEV;
+
+       /* khubd will finish the reset later */
+       if (ehci_is_TDI(ehci))
+               ehci_writel(ehci, status | (PORT_RESET & ~PORT_RWC_BITS), reg);
+       else
+               ehci_writel(ehci, status | PORT_RESET, reg);
+
+       return 0;
+}
+
+#else
+
+#define ci_start_port_reset    NULL
+
+#endif
+
 /* The below code is based on tegra ehci driver */
 static int ci_imx_ehci_hub_control(
        struct usb_hcd  *hcd,
@@ -539,4 +571,5 @@ void ci_hdrc_host_driver_init(void)
        ci_ehci_hc_driver.bus_suspend = ci_ehci_bus_suspend;
        ci_ehci_hc_driver.bus_resume = ci_imx_ehci_bus_resume;
        ci_ehci_hc_driver.hub_control = ci_imx_ehci_hub_control;
+       ci_ehci_hc_driver.start_port_reset = ci_start_port_reset;
 }