If controller looses power during PM suspend then re-initialize
it. We use the DEBUG_CFG register to track if controller lost power
or was reset in PM suspend.
Move all initialization code into dwc3_ti_init() so it can be re-used.
Signed-off-by: Roger Quadros <rogerq@xxxxxxxxxx>
---
drivers/usb/dwc3/dwc3-am62.c | 82 +++++++++++++++++++++++++++++---------------
1 file changed, 55 insertions(+), 27 deletions(-)
diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
index fad151e78fd6..2192222faf4f 100644
--- a/drivers/usb/dwc3/dwc3-am62.c
+++ b/drivers/usb/dwc3/dwc3-am62.c
@@ -108,6 +108,9 @@
#define DWC3_AM62_AUTOSUSPEND_DELAY 100
+#define USBSS_DEBUG_CFG_OFF 0x7
+#define USBSS_DEBUG_CFG_DISABLED 0x7
+
struct dwc3_am62 {
struct device *dev;
void __iomem *usbss;
@@ -117,6 +120,7 @@ struct dwc3_am62 {
unsigned int offset;
unsigned int vbus_divider;
u32 wakeup_stat;
+ void __iomem *phy;
};
static const int dwc3_ti_rate_table[] = { /* in KHZ */
@@ -184,15 +188,47 @@ static int phy_syscon_pll_refclk(struct dwc3_am62 *am62)
return 0;
}
+static int dwc3_ti_init(struct dwc3_am62 *am62)
+{
+ int ret;
+ u32 reg;
+
+ /* Read the syscon property and set the rate code */
+ ret = phy_syscon_pll_refclk(am62);
+ if (ret)
+ return ret;
+
+ /* Workaround Errata i2409 */
+ if (am62->phy) {
+ reg = readl(am62->phy + USB_PHY_PLL_REG12);
+ reg |= USB_PHY_PLL_LDO_REF_EN | USB_PHY_PLL_LDO_REF_EN_EN;
+ writel(reg, am62->phy + USB_PHY_PLL_REG12);
+ }
+
+ /* VBUS divider select */
+ reg = dwc3_ti_readl(am62, USBSS_PHY_CONFIG);
+ if (am62->vbus_divider)
+ reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
+
+ dwc3_ti_writel(am62, USBSS_PHY_CONFIG, reg);
+
+ clk_prepare_enable(am62->usb2_refclk);
+
+ /* Set mode valid bit to indicate role is valid */
+ reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL);
+ reg |= USBSS_MODE_VALID;
+ dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg);
+
+ return 0;
+}
+
static int dwc3_ti_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = pdev->dev.of_node;
struct dwc3_am62 *am62;
unsigned long rate;
- void __iomem *phy;
int i, ret;
- u32 reg;
am62 = devm_kzalloc(dev, sizeof(*am62), GFP_KERNEL);
if (!am62)
@@ -228,29 +264,17 @@ static int dwc3_ti_probe(struct platform_device *pdev)
am62->rate_code = i;
- /* Read the syscon property and set the rate code */
- ret = phy_syscon_pll_refclk(am62);
- if (ret)
- return ret;
-
- /* Workaround Errata i2409 */
- phy = devm_platform_ioremap_resource(pdev, 1);
- if (IS_ERR(phy)) {
+ am62->phy = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(am62->phy)) {
dev_err(dev, "can't map PHY IOMEM resource. Won't apply i2409 fix.\n");
- phy = NULL;
- } else {
- reg = readl(phy + USB_PHY_PLL_REG12);
- reg |= USB_PHY_PLL_LDO_REF_EN | USB_PHY_PLL_LDO_REF_EN_EN;
- writel(reg, phy + USB_PHY_PLL_REG12);
+ am62->phy = NULL;
}
- /* VBUS divider select */
am62->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
- reg = dwc3_ti_readl(am62, USBSS_PHY_CONFIG);
- if (am62->vbus_divider)
- reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
- dwc3_ti_writel(am62, USBSS_PHY_CONFIG, reg);
+ ret = dwc3_ti_init(am62);
+ if (ret)
+ return ret;
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
@@ -258,7 +282,6 @@ static int dwc3_ti_probe(struct platform_device *pdev)
* Don't ignore its dependencies with its children
*/
pm_suspend_ignore_children(dev, false);
- clk_prepare_enable(am62->usb2_refclk);
pm_runtime_get_noresume(dev);
ret = of_platform_populate(node, NULL, NULL, dev);
@@ -267,11 +290,6 @@ static int dwc3_ti_probe(struct platform_device *pdev)
goto err_pm_disable;
}
- /* Set mode valid bit to indicate role is valid */
- reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL);
- reg |= USBSS_MODE_VALID;
- dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg);
-
/* Device has capability to wakeup system from sleep */
device_set_wakeup_capable(dev, true);
ret = device_wakeup_enable(dev);
@@ -338,6 +356,9 @@ static int dwc3_ti_suspend_common(struct device *dev)
dwc3_ti_writel(am62, USBSS_WAKEUP_STAT, USBSS_WAKEUP_STAT_CLR);
}
+ /* just to track if module resets on suspend */
+ dwc3_ti_writel(am62, USBSS_DEBUG_CFG, USBSS_DEBUG_CFG_DISABLED);
+
clk_disable_unprepare(am62->usb2_refclk);
return 0;
@@ -348,7 +369,14 @@ static int dwc3_ti_resume_common(struct device *dev)
struct dwc3_am62 *am62 = dev_get_drvdata(dev);
u32 reg;
- clk_prepare_enable(am62->usb2_refclk);
+ reg = dwc3_ti_readl(am62, USBSS_DEBUG_CFG);
+ if (reg != USBSS_DEBUG_CFG_DISABLED) {
+ /* lost power/context */
+ dwc3_ti_init(am62);
+ } else {
+ dwc3_ti_writel(am62, USBSS_DEBUG_CFG, USBSS_DEBUG_CFG_OFF);
+ clk_prepare_enable(am62->usb2_refclk);
+ }
if (device_may_wakeup(dev)) {
/* Clear wakeup config enable bits */
---
base-commit: adc218676eef25575469234709c2d87185ca223a
change-id: 20241122-am62-dwc3-io-ddr-3bcb683a91a0
Best regards,
--
Roger Quadros <rogerq@xxxxxxxxxx>
