> -----Original Message-----
> From: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
> Sent: Wednesday, January 26, 2022 10:14 PM
> To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; Rob Herring
> <robh+dt@xxxxxxxxxx>; Shawn Guo <shawnguo@xxxxxxxxxx>; Sascha Hauer
> <s.hauer@xxxxxxxxxxxxxx>; Fabio Estevam <festevam@xxxxxxxxx>
> Cc: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>; dl-linux-imx
> <linux-imx@xxxxxxx>; linux-usb@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; Jun Li
> <jun.li@xxxxxxx>
> Subject: [PATCH v4 3/4] usb: dwc3: imx8mp: Add support for setting SOC
> specific flags
>
> The i.MX8MP glue layer has support for the following flags:
> * over-current polarity
> * PWR pad polarity
> * controlling PPC flag in HCCPARAMS register
> * permanent port attach for usb2 & usb3 port
>
> Allow setting these flags by supporting specific flags in the glue node.
> In order to get this to work an additional IORESOURCE_MEM and clock is
> necessary. For backward compatibility this is purely optional.
>
> Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
> ---
> drivers/usb/dwc3/dwc3-imx8mp.c | 62 ++++++++++++++++++++++++++++++++++
> 1 file changed, 62 insertions(+)
>
> diff --git a/drivers/usb/dwc3/dwc3-imx8mp.c
> b/drivers/usb/dwc3/dwc3-imx8mp.c
> index 1c8fe657b3a9..5a96b66bf237 100644
> --- a/drivers/usb/dwc3/dwc3-imx8mp.c
> +++ b/drivers/usb/dwc3/dwc3-imx8mp.c
> @@ -36,10 +36,22 @@
>
> #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_imx8mp {
> struct device *dev;
> struct platform_device *dwc3;
> void __iomem *hsio_blk_base;
> + void __iomem *glue_base;
> struct clk *hsio_clk;
> struct clk *suspend_clk;
> int irq;
> @@ -47,6 +59,42 @@ struct dwc3_imx8mp {
> bool wakeup_pending;
> };
>
> +static void imx8mp_configure_glue(struct dwc3_imx8mp *dwc3_imx)
> +{
> + struct device *dev = dwc3_imx->dev;
> + u32 value;
> +
> + if (!dwc3_imx->glue_base)
> + return;
> +
> + value = readl(dwc3_imx->glue_base + USB_CTRL0);
> +
> + if (device_property_read_bool(dev, "fsl,permanently-attached"))
> + value |= (USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);
> + else
> + value &= ~(USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);
> +
> + if (device_property_read_bool(dev,
> "fsl,disable-port-power-control"))
> + value &= ~(USB_CTRL0_PORTPWR_EN);
> + else
> + value |= USB_CTRL0_PORTPWR_EN;
> +
> + writel(value, dwc3_imx->glue_base + USB_CTRL0);
> +
> + value = readl(dwc3_imx->glue_base + USB_CTRL1);
> + if (device_property_read_bool(dev, "fsl,over-current-active-low"))
> + value |= USB_CTRL1_OC_POLARITY;
> + else
> + value &= ~USB_CTRL1_OC_POLARITY;
> +
> + if (device_property_read_bool(dev, "fsl,power-active-low"))
> + value |= USB_CTRL1_PWR_POLARITY;
> + else
> + value &= ~USB_CTRL1_PWR_POLARITY;
I think you don't need a value update&write if property is not present.
> +
> + writel(value, dwc3_imx->glue_base + USB_CTRL1);
> +}
> +
> static void dwc3_imx8mp_wakeup_enable(struct dwc3_imx8mp *dwc3_imx)
> {
> struct dwc3 *dwc3 = platform_get_drvdata(dwc3_imx->dwc3);
> @@ -100,6 +148,7 @@ static int dwc3_imx8mp_probe(struct platform_device
> *pdev)
> struct device *dev = &pdev->dev;
> struct device_node *dwc3_np, *node = dev->of_node;
> struct dwc3_imx8mp *dwc3_imx;
> + struct resource *res;
Looks like this is not used anywhere, remove it.
> int err, irq;
>
> if (!node) {
> @@ -119,6 +168,15 @@ static int dwc3_imx8mp_probe(struct platform_device
> *pdev)
> if (IS_ERR(dwc3_imx->hsio_blk_base))
> return PTR_ERR(dwc3_imx->hsio_blk_base);
>
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> + if (!res) {
> + dev_warn(dev, "Base address for glue layer missing. Continuing
> without, some features are missing though.");
> + } else {
> + dwc3_imx->glue_base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(dwc3_imx->glue_base))
> + return PTR_ERR(dwc3_imx->glue_base);
> + }
> +
> dwc3_imx->hsio_clk = devm_clk_get(dev, "hsio");
> if (IS_ERR(dwc3_imx->hsio_clk)) {
> err = PTR_ERR(dwc3_imx->hsio_clk);
> @@ -152,6 +210,8 @@ static int dwc3_imx8mp_probe(struct platform_device
> *pdev)
> }
> dwc3_imx->irq = irq;
>
> + imx8mp_configure_glue(dwc3_imx);
> +
> pm_runtime_set_active(dev);
> pm_runtime_enable(dev);
> err = pm_runtime_get_sync(dev);
> @@ -252,6 +312,8 @@ static int __maybe_unused dwc3_imx8mp_resume(struct
> dwc3_imx8mp *dwc3_imx,
> dwc3_imx8mp_wakeup_disable(dwc3_imx);
> dwc3_imx->pm_suspended = false;
>
> + imx8mp_configure_glue(dwc3_imx);
> +
I guess this is to restore the settings if we experienced a power lost,
Please add some comments.
thanks
Li Jun
> if (dwc3_imx->wakeup_pending) {
> dwc3_imx->wakeup_pending = false;
> if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE) {
> --
> 2.25.1
