diff options
| author | Changming Huang <jerry.huang@nxp.com> | 2016-11-29 13:45:38 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-12-05 15:13:58 +0100 |
| commit | 9d4b82706357f2eb23f45309227fc94d11eea255 (patch) | |
| tree | 6cfe74d0824423d75256a71587bec8d73e24b032 /drivers/usb/host/ehci.h | |
| parent | 22547c4cc4fe20698a6a85a55b8788859134b8e4 (diff) | |
| download | linux-9d4b82706357f2eb23f45309227fc94d11eea255.tar.gz linux-9d4b82706357f2eb23f45309227fc94d11eea255.tar.bz2 linux-9d4b82706357f2eb23f45309227fc94d11eea255.zip | |
fsl/usb: Workarourd for USB erratum-A005697
The EHCI specification states the following in the SUSP bit description:
In the Suspend state, the port is sensitive to resume detection.
Note that the bit status does not change until the port is suspended and
that there may be a delay in suspending a port if there is a transaction
currently in progress on the USB.
However, in NXP USBDR controller, the PORTSCx[SUSP] bit changes immediately
when the application sets it and not when the port is actually suspended.
So the application must wait for at least 10 milliseconds after a port
indicates that it is suspended, to make sure this port has entered
suspended state before initiating this port resume using the Force Port
Resume bit. This bit is for NXP controller, not EHCI compatible.
Signed-off-by: Changming Huang <jerry.huang@nxp.com>
Signed-off-by: Ramneek Mehresh <ramneek.mehresh@nxp.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/ehci.h')
| -rw-r--r-- | drivers/usb/host/ehci.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h index 3f3b74aeca97..a8e36170d8b8 100644 --- a/drivers/usb/host/ehci.h +++ b/drivers/usb/host/ehci.h @@ -219,6 +219,7 @@ struct ehci_hcd { /* one per controller */ unsigned no_selective_suspend:1; unsigned has_fsl_port_bug:1; /* FreeScale */ unsigned has_fsl_hs_errata:1; /* Freescale HS quirk */ + unsigned has_fsl_susp_errata:1; /* NXP SUSP quirk */ unsigned big_endian_mmio:1; unsigned big_endian_desc:1; unsigned big_endian_capbase:1; @@ -710,6 +711,13 @@ ehci_port_speed(struct ehci_hcd *ehci, unsigned int portsc) #endif /* + * Some Freescale/NXP processors have an erratum (USB A-005697) + * in which we need to wait for 10ms for bus to enter suspend mode + * after setting SUSP bit. + */ +#define ehci_has_fsl_susp_errata(e) ((e)->has_fsl_susp_errata) + +/* * While most USB host controllers implement their registers in * little-endian format, a minority (celleb companion chip) implement * them in big endian format. |