Newer DWC3 controllers can be built for USB 2.0-only mode, where
most of the USB 3.0 circuitry is left out. To support this mode,
the driver must limit the speed programmed into the DCFG register
to Hi-Speed or lower.
Reads and writes to the PIPECTL register are left as-is, since
they should be no-ops in USB 2.0-only mode. Calls to phy_init()
etc. for the USB3 phy are also left as-is, since the no-op USB3
phy should be used for USB 2.0-only mode controllers.
Signed-off-by: Paul Zimmerman <paulz@xxxxxxxxxxxx>
---
Hi Felipe,
Does this look OK to you? I think it is fine to leave the PIPECTL
accesses and the phy_init() calls as-is, but if you would prefer
that I also conditionalize those I can do that. We have at least
one customer who will need this feature fairly soon, so we would
like to get this in without too much delay, although I guess we
missed the 3.16 merge window.
-Paul
drivers/usb/dwc3/core.c | 7 +++++++
drivers/usb/dwc3/core.h | 13 +++++++++++++
2 files changed, 20 insertions(+)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 3f59c12..c67f4f4 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -386,6 +386,13 @@ static int dwc3_core_init(struct dwc3 *dwc)
}
dwc->revision = reg;
+ /* Handle USB2.0-only core configuration */
+ if (DWC3_GHWPARAMS3_SSPHY_IFC(dwc->hwparams.hwparams3) ==
+ DWC3_GHWPARAMS3_SSPHY_IFC_DIS) {
+ if (dwc->maximum_speed == USB_SPEED_SUPER)
+ dwc->maximum_speed = USB_SPEED_HIGH;
+ }
+
/* issue device SoftReset too */
timeout = jiffies + msecs_to_jiffies(500);
dwc3_writel(dwc->regs, DWC3_DCTL, DWC3_DCTL_CSFTRST);
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 57332e3..48fb264 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -191,6 +191,19 @@
#define DWC3_GHWPARAMS1_PWROPT(n) ((n) << 24)
#define DWC3_GHWPARAMS1_PWROPT_MASK DWC3_GHWPARAMS1_PWROPT(3)
+/* Global HWPARAMS3 Register */
+#define DWC3_GHWPARAMS3_SSPHY_IFC(n) ((n) & 3)
+#define DWC3_GHWPARAMS3_SSPHY_IFC_DIS 0
+#define DWC3_GHWPARAMS3_SSPHY_IFC_ENA 1
+#define DWC3_GHWPARAMS3_HSPHY_IFC(n) (((n) & (3 << 2)) >> 2)
+#define DWC3_GHWPARAMS3_HSPHY_IFC_DIS 0
+#define DWC3_GHWPARAMS3_HSPHY_IFC_UTMI 1
+#define DWC3_GHWPARAMS3_HSPHY_IFC_ULPI 2
+#define DWC3_GHWPARAMS3_HSPHY_IFC_UTMI_ULPI 3
+#define DWC3_GHWPARAMS3_FSPHY_IFC(n) (((n) & (3 << 4)) >> 4)
+#define DWC3_GHWPARAMS3_FSPHY_IFC_DIS 0
+#define DWC3_GHWPARAMS3_FSPHY_IFC_ENA 1
+
/* Global HWPARAMS4 Register */
#define DWC3_GHWPARAMS4_HIBER_SCRATCHBUFS(n) (((n) & (0x0f << 13)) >> 13)
#define DWC3_MAX_HIBER_SCRATCHBUFS 15
--
1.8.5
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