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>
---
Changes in v5:
* Added comment why reprogramming is necessary in resume
drivers/usb/dwc3/dwc3-imx8mp.c | 63 ++++++++++++++++++++++++++++++++++
1 file changed, 63 insertions(+)
diff --git a/drivers/usb/dwc3/dwc3-imx8mp.c b/drivers/usb/dwc3/dwc3-imx8mp.c
index 1c8fe657b3a9..174f07614318 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;
+
+ 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;
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 +312,9 @@ static int __maybe_unused dwc3_imx8mp_resume(struct dwc3_imx8mp *dwc3_imx,
dwc3_imx8mp_wakeup_disable(dwc3_imx);
dwc3_imx->pm_suspended = false;
+ /* Upon power loss any previous configuration is lost, restore it */
+ imx8mp_configure_glue(dwc3_imx);
+
if (dwc3_imx->wakeup_pending) {
dwc3_imx->wakeup_pending = false;
if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE) {
--
2.25.1
