| Message ID | 20220126000253.1586760-5-robert.hancock@calian.com (mailing list archive) |
|---|---|
| State | Superseded |
| 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
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; + } + + 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
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(+)