This patch adds a USB GPIO based reset for dwc3-xilinx driver. The PHY
needs to be reset after the completion of phy initialization. As part
of the reset, check for gpio-reset binding before toggling the pin.
This feature is advantageous when the user toggle GPIO to trigger the
ULPI-PHY reset.
Delay of milliseconds is added in between low and high to meet the setup
and hold time requirement of the reset. The reset-gpio error handling is
added for error notification.
Some GPIO controllers must be accessed using message-based buses, like
I2C or SPI, to address this problem, updates GPIO access with sleep API.
This reset is specific to the zynqMp.
Signed-off-by: Piyush Mehta <piyush.mehta@xilinx.com>
Link: https://lore.kernel.org/r/20220504075309.6244-3-piyush.mehta@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It appears that the PIPE clock should not be selected when only USB 2.0
is being used in the design and no USB 3.0 reference clock is used.
Also, the core resets are not required if a USB3 PHY is not in use, and
will break things if USB3 is actually used but the PHY entry is not
listed in the device tree.
Skip core resets and register settings that are only required for
USB3 mode when no USB3 PHY is specified in the device tree.
Fixes: 84770f028f ("usb: dwc3: Add driver for Xilinx platforms")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Link: https://lore.kernel.org/r/20220126000253.1586760-2-robert.hancock@calian.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a new driver for supporting Xilinx platforms. This driver is used
for some sequence of operations required for Xilinx USB controllers.
This driver is also used to choose between PIPE clock coming from SerDes
and the Suspend Clock. Before the controller is out of reset, the clock
selection should be changed to PIPE clock in order to make the USB
controller work. There is a register added in Xilinx USB controller
register space for the same.
Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Link: https://lore.kernel.org/r/1615963949-75320-3-git-send-email-manish.narani@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
