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| author |   Martin Blumenstingl <martin.blumenstingl@googlemail.com> | 2018-03-03 22:43:03 +0100 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-09 09:43:52 -0800 |
| commit | 4e88d4c083016454f179686529ae65d70b933b58 (patch) | |
| tree | 2f124819d2fb5fe17dbba4e5c1eaabdec72a70a3 /include/linux/usb | |
| parent | dt-bindings: usb: add the documentation for USB HCDs (diff) | |
| download | linux-dev-4e88d4c083016454f179686529ae65d70b933b58.tar.xz linux-dev-4e88d4c083016454f179686529ae65d70b933b58.zip | |
usb: add a flag to skip PHY initialization to struct usb_hcd
The USB HCD core driver parses the device-tree node for "phys" and
"usb-phys" properties. It also manages the power state of these PHYs
automatically.
However, drivers may opt-out of this behavior by setting "phy" or
"usb_phy" in struct usb_hcd to a non-null value. An example where this
is required is the "Qualcomm USB2 controller", implemented by the
chipidea driver. The hardware requires that the PHY is only powered on
after the "reset completed" event from the controller is received.
A follow-up patch will allow the USB HCD core driver to manage more than
one PHY. Add a new "skip_phy_initialization" bitflag to struct usb_hcd
so drivers can opt-out of any PHY management provided by the USB HCD
core driver.
This also updates the existing drivers so they use the new flag if they
want to opt out of the PHY management provided by the USB HCD core
driver. This means that for these drivers the new "multiple PHY"
handling (which will be added in a follow-up patch) will be disabled as
well.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Peter Chen <peter.chen@nxp.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.con>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/usb')
| -rw-r--r-- | include/linux/usb/hcd.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h index 176900528822..693502c84c04 100644 --- a/include/linux/usb/hcd.h +++ b/include/linux/usb/hcd.h @@ -151,6 +151,12 @@ struct usb_hcd { unsigned msix_enabled:1; /* driver has MSI-X enabled? */ unsigned msi_enabled:1; /* driver has MSI enabled? */ unsigned remove_phy:1; /* auto-remove USB phy */ + /* + * do not manage the PHY state in the HCD core, instead let the driver + * handle this (for example if the PHY can only be turned on after a + * specific event) + */ + unsigned skip_phy_initialization:1; /* The next flag is a stopgap, to be removed when all the HCDs * support the new root-hub polling mechanism. */ |