Hi Bin Meng,
-----Original Message----- From: Bin Meng bmeng.cn@gmail.com Sent: Thursday, March 3, 2022 2:18 PM To: Michal Simek michals@xilinx.com Cc: U-Boot Mailing List u-boot@lists.denx.de; git git@xilinx.com; T Karthik Reddy tkarthik@xilinx.com; Angus Ainslie angus@akkea.ca; Kunihiko Hayashi hayashi.kunihiko@socionext.com; Marek Vasut marex@denx.de; Michael Walle michael@walle.cc; Priyanka Jain priyanka.jain@nxp.com; Simon Glass sjg@chromium.org Subject: Re: [PATCH] usb: dwc3: Add support to reset usb ULPI phy
On Wed, Feb 23, 2022 at 11:07 PM Michal Simek michal.simek@xilinx.com wrote:
From: T Karthik Reddy t.karthik.reddy@xilinx.com
When usb PHY initialization is done, the PHY need to be reset.
Signed-off-by: T Karthik Reddy t.karthik.reddy@xilinx.com Signed-off-by: Michal Simek michal.simek@xilinx.com
drivers/usb/dwc3/Kconfig | 2 +- drivers/usb/dwc3/dwc3-generic.c | 28
++++++++++++++++++++++++++++
2 files changed, 29 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig index 62aa65bf0cd2..685bda3729e5 100644 --- a/drivers/usb/dwc3/Kconfig +++ b/drivers/usb/dwc3/Kconfig @@ -25,7 +25,7 @@ config USB_DWC3_OMAP
config USB_DWC3_GENERIC bool "Generic implementation of a DWC3 wrapper (aka dwc3 glue)"
depends on DM_USB && USB_DWC3 && MISC
depends on DM_USB && USB_DWC3 && MISC && DM_GPIO help Select this for Xilinx ZynqMP and similar Platforms. This wrapper supports Host and Peripheral operation modes.diff --git a/drivers/usb/dwc3/dwc3-generic.c b/drivers/usb/dwc3/dwc3-generic.c index b1e019b5b91a..17d35a6dc60c 100644 --- a/drivers/usb/dwc3/dwc3-generic.c +++ b/drivers/usb/dwc3/dwc3-generic.c @@ -25,6 +25,7 @@ #include <reset.h> #include <clk.h> #include <usb/xhci.h> +#include <asm/gpio.h>
struct dwc3_glue_data { struct clk_bulk clks; @@ -42,6 +43,7 @@ struct dwc3_generic_priv { void *base; struct dwc3 dwc3; struct phy_bulk phys;
struct gpio_desc ulpi_reset;};
struct dwc3_generic_host_priv { @@ -77,6 +79,26 @@ static int dwc3_generic_probe(struct udevice *dev, if (rc && rc != -ENOTSUPP) return rc;
if (device_is_compatible(dev->parent, "xlnx,zynqmp-dwc3")) {rc = gpio_request_by_name(dev->parent, "reset-gpios", 0,&priv->ulpi_reset, GPIOD_ACTIVE_LOW);if (rc != -EBUSY && rc)return rc;What happens if rc == -EBUSY?
Every time we do usb reset, gpio is requested again and returns EBUSY. We want to avoid returning probe with error, if rc == -EBUSY.
Thanks T Karthik
/* Toggle ulpi to reset the phy. */rc = dm_gpio_set_value(&priv->ulpi_reset, 1);if (rc)return rc;mdelay(5);rc = dm_gpio_set_value(&priv->ulpi_reset, 0);if (rc)return rc;mdelay(5);}if (device_is_compatible(dev->parent, "rockchip,rk3399-dwc3")) reset_deassert_bulk(&glue->resets);@@ -98,6 +120,12 @@ static int dwc3_generic_remove(struct udevice *dev, { struct dwc3 *dwc3 = &priv->dwc3;
if (device_is_compatible(dev->parent, "xlnx,zynqmp-dwc3")) {struct gpio_desc *ulpi_reset = &priv->ulpi_reset;dm_gpio_free(ulpi_reset->dev, ulpi_reset);}dwc3_remove(dwc3); dwc3_shutdown_phy(dev, &priv->phys); unmap_physmem(dwc3->regs, MAP_NOCACHE);Regards, Bin