As per USB specification, in the Suspend state, the status bit does
not change until the port is suspended. However, there may be a delay
in suspending a port if there is a transaction currently in progress
on the bus.
In the USBDR controller, the PORTSCx[SUSP] bit changes immediately when
the application sets it and not when the port is actually suspended
Workaround for this issue involves waiting for a minimum of 10ms to
allow the controller to go into SUSPEND state before proceeding ahead
Signed-off-by: Ramneek Mehresh <ramneek.mehresh@xxxxxxxxxxxxx>
Signed-off-by: Nikhil Badola <nikhil.badola@xxxxxxxxxxxxx>
---
drivers/usb/host/ehci-fsl.c | 3 +++
drivers/usb/host/ehci-hub.c | 2 ++
drivers/usb/host/ehci.h | 12 ++++++++++++
drivers/usb/host/fsl-mph-dr-of.c | 5 +++++
include/linux/fsl_devices.h | 1 +
5 files changed, 23 insertions(+)
diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 202dafb..8904aae 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -278,6 +278,9 @@ static int ehci_fsl_usb_setup(struct ehci_hcd *ehci)
out_be32(non_ehci + FSL_SOC_USB_SNOOP2, 0x80000000 | SNOOP_SIZE_2GB);
}
+ if (pdata->has_fsl_erratum_a005697 == 1)
+ ehci->has_fsl_susp_errata = 1;
+
if ((pdata->operating_mode == FSL_USB2_DR_HOST) ||
(pdata->operating_mode == FSL_USB2_DR_OTG))
if (ehci_fsl_setup_phy(hcd, pdata->phy_mode, 0))
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 22abb68..7eac923 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -303,6 +303,8 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
USB_PORT_STAT_HIGH_SPEED)
fs_idle_delay = true;
ehci_writel(ehci, t2, reg);
+ if (ehci_has_fsl_susp_errata(ehci))
+ usleep_range(10000, 20000);
changed = 1;
}
}
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index f700157..817eab5 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -215,6 +215,7 @@ struct ehci_hcd { /* one per controller */
/* SILICON QUIRKS */
unsigned no_selective_suspend:1;
unsigned has_fsl_port_bug:1; /* FreeScale */
+ unsigned has_fsl_susp_errata;/* Freescale SUSP quirk */
unsigned big_endian_mmio:1;
unsigned big_endian_desc:1;
unsigned big_endian_capbase:1;
@@ -675,6 +676,17 @@ ehci_port_speed(struct ehci_hcd *ehci, unsigned int portsc)
#define ehci_port_speed(ehci, portsc) USB_PORT_STAT_HIGH_SPEED
#endif
+#if defined(CONFIG_PPC_85xx)
+/*
+ * Some Freescale processors have an erratum (USB A-005697) in which
+ * we need to wait for 10ms for bus to go into suspend mode after
+ * setting SUSP bit
+ */
+#define ehci_has_fsl_susp_errata(e) ((e)->has_fsl_susp_errata)
+#else
+#define ehci_has_fsl_susp_errata(e) (0)
+#endif
+
/*-------------------------------------------------------------------------*/
#ifdef CONFIG_PPC_83xx
diff --git a/drivers/usb/host/fsl-mph-dr-of.c b/drivers/usb/host/fsl-mph-dr-of.c
index 9f73141..870b50a 100644
--- a/drivers/usb/host/fsl-mph-dr-of.c
+++ b/drivers/usb/host/fsl-mph-dr-of.c
@@ -222,6 +222,11 @@ static int fsl_usb2_mph_dr_of_probe(struct platform_device *ofdev)
else
pdata->has_fsl_erratum_a007792 = 0;
+ if (of_get_property(np, "fsl,usb-erratum-a005697", NULL))
+ pdata->has_fsl_erratum_a005697 = 1;
+ else
+ pdata->has_fsl_erratum_a005697 = 0;
+
/*
* Determine whether phy_clk_valid needs to be checked
* by reading property in device tree
diff --git a/include/linux/fsl_devices.h b/include/linux/fsl_devices.h
index cebdbbb..42bf841 100644
--- a/include/linux/fsl_devices.h
+++ b/include/linux/fsl_devices.h
@@ -100,6 +100,7 @@ struct fsl_usb2_platform_data {
unsigned already_suspended:1;
unsigned has_fsl_erratum_a007792:1;
unsigned check_phy_clk_valid:1;
+ unsigned has_fsl_erratum_a005697:1;
/* register save area for suspend/resume */
u32 pm_command;
--
2.1.0
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