| Message ID | 20220126000253.1586760-1-robert.hancock@calian.com |
|---|---|
| Headers | show |
| Series | Xilinx ZynqMP USB fixes | expand |
On Tue, 2022-01-25 at 18:02 -0600, Robert Hancock wrote: > Hook up an optional GPIO-based reset for the connected USB ULPI PHY > device. This is typically already done by the first-stage boot loader, > however it can be more robust to ensure this reset is done prior to > loading the driver in Linux. > > Based on a patch "usb: dwc3: xilinx: Add gpio-reset support" in the > Xilinx kernel tree by Piyush Mehta <piyush.mehta@xilinx.com>. > > Signed-off-by: Robert Hancock <robert.hancock@calian.com> > --- > drivers/usb/dwc3/dwc3-xilinx.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/usb/dwc3/dwc3-xilinx.c b/drivers/usb/dwc3/dwc3-xilinx.c > index e14ac15e24c3..0778236509bf 100644 > --- a/drivers/usb/dwc3/dwc3-xilinx.c > +++ b/drivers/usb/dwc3/dwc3-xilinx.c > @@ -11,6 +11,7 @@ > #include <linux/slab.h> > #include <linux/clk.h> > #include <linux/of.h> > +#include <linux/gpio/consumer.h> > #include <linux/platform_device.h> > #include <linux/dma-mapping.h> > #include <linux/of_platform.h> > @@ -101,6 +102,7 @@ static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx > *priv_data) > struct phy *usb3_phy; > int ret; > u32 reg; > + struct gpio_desc *reset_gpio; > > usb3_phy = devm_phy_optional_get(dev, "usb3-phy"); > if (IS_ERR(usb3_phy)) { > @@ -201,6 +203,22 @@ static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx > *priv_data) > } > > skip_usb3_phy: > + /* ulpi reset via gpio-modepin or gpio-framework driver */ > + reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); > + if (IS_ERR(reset_gpio)) { > + dev_err_probe(dev, PTR_ERR(reset_gpio), > + "Failed to bind reset gpio\n"); > + goto err; > Just noticed this forgets to set the error code to PTR_ERR(reset_gpio) and breaks in the deferred probe case. Also, this should be done earlier to avoid bailing out too late in that case. Will resubmit a new patchset with this fix for the remaining two patches (first 2 in this series were already merged). > + } > + > + if (reset_gpio) { > + /* Toggle ulpi to reset the phy. */ > + gpiod_set_value(reset_gpio, 0); > + usleep_range(5000, 10000); /* delay */ > + gpiod_set_value(reset_gpio, 1); > + usleep_range(5000, 10000); /* delay */ > + } > + > /* > * This routes the USB DMA traffic to go through FPD path instead > * of reaching DDR directly. This traffic routing is needed to
Some fixes related to the Xilinx ZynqMP DWC3 wrapper driver to allow ZynqMP USB to work properly when the hardware is configured in USB 2.0-only mode. Changes since v6: -skip USB core resets and register settings which are not necessary when USB3 PHY is not specified -added patches to implement ULPI PHY reset in driver Changes since v5: -code formatting fixes, no functional change Changes since v4: -dropped DWC3 core patches as they are superseded by Sean Anderson's patchset "usb: dwc3: Calculate REFCLKPER et. al. from reference clock", ZynqMP-specific patches unchanged Changes since v3: -fixed DT schema dt-doc-validate error Changes since v2: -additional kerneldoc fixes Changes since v1: -added DT binding documentation for new attribute -kerneldoc formatting and reworded comments Robert Hancock (4): usb: dwc3: xilinx: Skip resets and USB3 register settings for USB2.0 mode usb: dwc3: xilinx: Fix error handling when getting USB3 PHY dt-bindings: usb: dwc3-xilinx: Added reset-gpios usb: dwc3: xilinx: Add ULPI PHY reset handling .../devicetree/bindings/usb/dwc3-xilinx.yaml | 4 ++ drivers/usb/dwc3/dwc3-xilinx.c | 41 ++++++++++++++++--- 2 files changed, 40 insertions(+), 5 deletions(-)