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path: root/drivers/usb/dwc3/core.c
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Diffstat (limited to 'drivers/usb/dwc3/core.c')
-rw-r--r--drivers/usb/dwc3/core.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 0104a80b185e..643239d7d370 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -26,6 +26,7 @@
#include <linux/acpi.h>
#include <linux/pinctrl/consumer.h>
#include <linux/reset.h>
+#include <linux/bitfield.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
@@ -336,6 +337,29 @@ static void dwc3_frame_length_adjustment(struct dwc3 *dwc)
}
/**
+ * dwc3_ref_clk_period - Reference clock period configuration
+ * Default reference clock period depends on hardware
+ * configuration. For systems with reference clock that differs
+ * from the default, this will set clock period in DWC3_GUCTL
+ * register.
+ * @dwc: Pointer to our controller context structure
+ * @ref_clk_per: reference clock period in ns
+ */
+static void dwc3_ref_clk_period(struct dwc3 *dwc)
+{
+ u32 reg;
+
+ if (dwc->ref_clk_per == 0)
+ return;
+
+ reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
+ reg &= ~DWC3_GUCTL_REFCLKPER_MASK;
+ reg |= FIELD_PREP(DWC3_GUCTL_REFCLKPER_MASK, dwc->ref_clk_per);
+ dwc3_writel(dwc->regs, DWC3_GUCTL, reg);
+}
+
+
+/**
* dwc3_free_one_event_buffer - Frees one event buffer
* @dwc: Pointer to our controller context structure
* @evt: Pointer to event buffer to be freed
@@ -1007,6 +1031,9 @@ static int dwc3_core_init(struct dwc3 *dwc)
/* Adjust Frame Length */
dwc3_frame_length_adjustment(dwc);
+ /* Adjust Reference Clock Period */
+ dwc3_ref_clk_period(dwc);
+
dwc3_set_incr_burst_type(dwc);
usb_phy_set_suspend(dwc->usb2_phy, 0);
@@ -1389,6 +1416,8 @@ static void dwc3_get_properties(struct dwc3 *dwc)
&dwc->hsphy_interface);
device_property_read_u32(dev, "snps,quirk-frame-length-adjustment",
&dwc->fladj);
+ device_property_read_u32(dev, "snps,ref-clock-period-ns",
+ &dwc->ref_clk_per);
dwc->dis_metastability_quirk = device_property_read_bool(dev,
"snps,dis_metastability_quirk");