[PATCH v3 3/3] usb: dwc3: introduce flatten model driver of i.MX Soc

[Xu Yang]

On Fri, Feb 06, 2026 at 11:03:42AM -0500, Frank Li wrote:
> On Fri, Feb 06, 2026 at 06:18:51PM +0800, Xu Yang wrote:
> > The i.MX USB glue and DWC3 core are closely coupled. Describe the i.MX
> > USB block in a single block will bring more benefits than a parent-
> > child relation. To support the flatten model devicetree, DWC3 USB core
> > driver already support to directly register and initialize the core in
> > glue layer using one device. And many notification can be received in
> > glue layer timely and proper actions can be executed accordingly.
> >
> > To align with mainstream, introduce a new driver to support flatten dwc3
> > devicetree model for i.MX Soc. Besides this driver disabling wakeup irq
> > when system is active, no other function change in this version compared
> > to dwc3-imx8mp.c
> >
> > Signed-off-by: Xu Yang <xu.yang_2 at nxp.com>
> >
> > ---
> > Changes in v3:
> >  - update compatible as nxp,imx8mp-dwc3
> > Changes in v2:
> >  - improve commit message
> >  - fix code style
> >  - add IRQF_NO_AUTOEN
> >  - remove pm_runtime_* in dwc3_imx_remove(), dwc3_core_remove()
> >    will do that
> > ---
> >  drivers/usb/dwc3/Kconfig    |  12 ++
> >  drivers/usb/dwc3/Makefile   |   1 +
> >  drivers/usb/dwc3/dwc3-imx.c | 429 ++++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 442 insertions(+)
> >
> > diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
> > index 240b15bc52cb..18169727a413 100644
> > --- a/drivers/usb/dwc3/Kconfig
> > +++ b/drivers/usb/dwc3/Kconfig
> > @@ -150,6 +150,18 @@ config USB_DWC3_IMX8MP
> >  	  functionality.
> >  	  Say 'Y' or 'M' if you have one such device.
> >
> > +config USB_DWC3_IMX
> > +	tristate "NXP iMX Platform"
> > +	depends on OF && COMMON_CLK
> > +	depends on (ARCH_MXC && ARM64) || COMPILE_TEST
> > +	default USB_DWC3
> > +	help
> > +	  NXP iMX SoC use DesignWare Core IP for USB2/3
> > +	  functionality.
> > +	  This driver also handles the wakeup feature outside
> > +	  of DesignWare Core.
> > +	  Say 'Y' or 'M' if you have one such device.
> > +
> >  config USB_DWC3_XILINX
> >  	tristate "Xilinx Platforms"
> >  	depends on (ARCH_ZYNQMP || COMPILE_TEST) && OF
> > diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> > index 073bef5309b5..f37971197203 100644
> > --- a/drivers/usb/dwc3/Makefile
> > +++ b/drivers/usb/dwc3/Makefile
> > @@ -55,6 +55,7 @@ obj-$(CONFIG_USB_DWC3_ST)		+= dwc3-st.o
> >  obj-$(CONFIG_USB_DWC3_QCOM)		+= dwc3-qcom.o
> >  obj-$(CONFIG_USB_DWC3_QCOM)		+= dwc3-qcom-legacy.o
> >  obj-$(CONFIG_USB_DWC3_IMX8MP)		+= dwc3-imx8mp.o
> > +obj-$(CONFIG_USB_DWC3_IMX)		+= dwc3-imx.o
> >  obj-$(CONFIG_USB_DWC3_XILINX)		+= dwc3-xilinx.o
> >  obj-$(CONFIG_USB_DWC3_OCTEON)		+= dwc3-octeon.o
> >  obj-$(CONFIG_USB_DWC3_RTK)		+= dwc3-rtk.o
> > diff --git a/drivers/usb/dwc3/dwc3-imx.c b/drivers/usb/dwc3/dwc3-imx.c
> > new file mode 100644
> > index 000000000000..3b154d075bcf
> > --- /dev/null
> > +++ b/drivers/usb/dwc3/dwc3-imx.c
> > @@ -0,0 +1,429 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * dwc3-imx.c - NXP i.MX Soc USB3 Specific Glue layer
> > + *
> > + * Copyright 2026 NXP
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +
> > +#include "core.h"
> > +#include "glue.h"
> > +
> > +/* USB wakeup registers */
> > +#define USB_WAKEUP_CTRL			0x00
> > +
> > +/* Global wakeup interrupt enable, also used to clear interrupt */
> > +#define USB_WAKEUP_EN			BIT(31)
> > +/* Wakeup from connect or disconnect, only for superspeed */
> > +#define USB_WAKEUP_SS_CONN		BIT(5)
> > +/* 0 select vbus_valid, 1 select sessvld */
> > +#define USB_WAKEUP_VBUS_SRC_SESS_VAL	BIT(4)
> > +/* Enable signal for wake up from u3 state */
> > +#define USB_WAKEUP_U3_EN		BIT(3)
> > +/* Enable signal for wake up from id change */
> > +#define USB_WAKEUP_ID_EN		BIT(2)
> > +/* Enable signal for wake up from vbus change */
> > +#define	USB_WAKEUP_VBUS_EN		BIT(1)
> > +/* Enable signal for wake up from dp/dm change */
> > +#define USB_WAKEUP_DPDM_EN		BIT(0)
> > +
> > +#define USB_WAKEUP_EN_MASK		GENMASK(5, 0)
> > +
> > +/* USB glue registers */
> > +#define USB_CTRL0		0x00
> > +#define USB_CTRL1		0x04
> > +
> > +#define USB_CTRL0_PORTPWR_EN	BIT(12) /* 1 - PPC enabled (default) */
> > +#define USB_CTRL0_USB3_FIXED	BIT(22) /* 1 - USB3 permanent attached */
> > +#define USB_CTRL0_USB2_FIXED	BIT(23) /* 1 - USB2 permanent attached */
> > +
> > +#define USB_CTRL1_OC_POLARITY	BIT(16) /* 0 - HIGH / 1 - LOW */
> > +#define USB_CTRL1_PWR_POLARITY	BIT(17) /* 0 - HIGH / 1 - LOW */
> > +
> > +struct dwc3_imx {
> > +	struct dwc3	dwc;
> > +	struct device	*dev;
> > +	void __iomem	*blkctl_base;
> > +	void __iomem	*glue_base;
> > +	struct clk	*hsio_clk;
> > +	struct clk	*suspend_clk;
> > +	int		irq;
> > +	bool		pm_suspended;
> > +	bool		wakeup_pending;
> > +};
> > +
> > +#define to_dwc3_imx(d) container_of((d), struct dwc3_imx, dwc)
> > +
> > +static void dwc3_imx_configure_glue(struct dwc3_imx *dwc_imx)
> > +{
> > +	struct device	*dev = dwc_imx->dev;
> > +	u32		value;
> > +
> > +	if (!dwc_imx->glue_base)
> > +		return;
> > +
> > +	value = readl(dwc_imx->glue_base + USB_CTRL0);
> > +
> > +	if (device_property_read_bool(dev, "fsl,permanently-attached"))
> 
> can you parse it at probe and save into dwc3_imx to avoid parse dts every
> resume()?

Sure. Good suggestion!

Thanks,
Xu Yang