@@ -16,6 +16,8 @@ Optional properties:
- tx-fifo-resize: determines if the FIFO *has* to be reallocated.
- snps,disable_scramble_quirk: true when SW should disable data scrambling.
Only really useful for FPGA builds.
+ - snps,has-lpm-erratum: true when DWC3 was configured with LPM Erratum enabled
+ - snps,lpm-nyet-threshold: LPM NYET threshold
This is usually a subnode to DWC3 glue to which it is connected.
@@ -654,6 +654,7 @@ static int dwc3_probe(struct platform_device *pdev)
struct device_node *node = dev->of_node;
struct resource *res;
struct dwc3 *dwc;
+ u8 lpm_nyet_threshold;
int ret;
@@ -709,16 +710,27 @@ static int dwc3_probe(struct platform_device *pdev)
*/
res->start -= DWC3_GLOBALS_REGS_START;
+ /* default to highest possible threshold */
+ lpm_nyet_threshold = 0xff;
+
if (node) {
dwc->maximum_speed = of_usb_get_maximum_speed(node);
+ dwc->has_lpm_erratum = of_property_read_bool(node,
+ "snps,has-lpm-erratum");
+ of_property_read_u8(node, "snps,lpm-nyet-threshold",
+ &lpm_nyet_threshold);
- dwc->needs_fifo_resize = of_property_read_bool(node, "tx-fifo-resize");
+ dwc->needs_fifo_resize = of_property_read_bool(node,
+ "tx-fifo-resize");
dwc->dr_mode = of_usb_get_dr_mode(node);
dwc->disable_scramble_quirk = of_property_read_bool(node,
"snps,disable_scramble_quirk");
} else if (pdata) {
dwc->maximum_speed = pdata->maximum_speed;
+ dwc->has_lpm_erratum = pdata->has_lpm_erratum;
+ if (pdata->lpm_nyet_threshold)
+ lpm_nyet_threshold = pdata->lpm_nyet_threshold;
dwc->needs_fifo_resize = pdata->tx_fifo_resize;
dwc->dr_mode = pdata->dr_mode;
@@ -730,6 +742,8 @@ static int dwc3_probe(struct platform_device *pdev)
if (dwc->maximum_speed == USB_SPEED_UNKNOWN)
dwc->maximum_speed = USB_SPEED_SUPER;
+ dwc->lpm_nyet_threshold = lpm_nyet_threshold;
+
ret = dwc3_core_get_phy(dwc);
if (ret)
return ret;
@@ -246,16 +246,19 @@
#define DWC3_DCTL_TRGTULST_SS_INACT (DWC3_DCTL_TRGTULST(6))
/* These apply for core versions 1.94a and later */
-#define DWC3_DCTL_KEEP_CONNECT (1 << 19)
-#define DWC3_DCTL_L1_HIBER_EN (1 << 18)
-#define DWC3_DCTL_CRS (1 << 17)
-#define DWC3_DCTL_CSS (1 << 16)
+#define DWC3_DCTL_LPM_ERRATA_MASK DWC3_DCTL_LPM_ERRATA(0xf)
+#define DWC3_DCTL_LPM_ERRATA(n) ((n) << 20)
-#define DWC3_DCTL_INITU2ENA (1 << 12)
-#define DWC3_DCTL_ACCEPTU2ENA (1 << 11)
-#define DWC3_DCTL_INITU1ENA (1 << 10)
-#define DWC3_DCTL_ACCEPTU1ENA (1 << 9)
-#define DWC3_DCTL_TSTCTRL_MASK (0xf << 1)
+#define DWC3_DCTL_KEEP_CONNECT (1 << 19)
+#define DWC3_DCTL_L1_HIBER_EN (1 << 18)
+#define DWC3_DCTL_CRS (1 << 17)
+#define DWC3_DCTL_CSS (1 << 16)
+
+#define DWC3_DCTL_INITU2ENA (1 << 12)
+#define DWC3_DCTL_ACCEPTU2ENA (1 << 11)
+#define DWC3_DCTL_INITU1ENA (1 << 10)
+#define DWC3_DCTL_ACCEPTU1ENA (1 << 9)
+#define DWC3_DCTL_TSTCTRL_MASK (0xf << 1)
#define DWC3_DCTL_ULSTCHNGREQ_MASK (0x0f << 5)
#define DWC3_DCTL_ULSTCHNGREQ(n) (((n) << 5) & DWC3_DCTL_ULSTCHNGREQ_MASK)
@@ -660,10 +663,13 @@ struct dwc3_scratchpad_array {
* @regset: debugfs pointer to regdump file
* @test_mode: true when we're entering a USB test mode
* @test_mode_nr: test feature selector
+ * @lpm_nyet_threshold: LPM NYET response threshold
* @delayed_status: true when gadget driver asks for delayed status
* @ep0_bounced: true when we used bounce buffer
* @ep0_expect_in: true when we expect a DATA IN transfer
* @has_hibernation: true when dwc3 was configured with Hibernation
+ * @has_lpm_erratum: true when core was configured with LPM Erratum. Note that
+ * there's now way for software to detect this in runtime.
* @is_selfpowered: true when we are selfpowered
* @is_fpga: true when we are using the FPGA board
* @needs_fifo_resize: not all users might want fifo resizing, flag it
@@ -764,11 +770,13 @@ struct dwc3 {
u8 test_mode;
u8 test_mode_nr;
+ u8 lpm_nyet_threshold;
unsigned delayed_status:1;
unsigned ep0_bounced:1;
unsigned ep0_expect_in:1;
unsigned has_hibernation:1;
+ unsigned has_lpm_erratum:1;
unsigned is_selfpowered:1;
unsigned is_fpga:1;
unsigned needs_fifo_resize:1;
@@ -2297,6 +2297,19 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
*/
reg |= DWC3_DCTL_HIRD_THRES(12);
+ /*
+ * When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
+ * DCFG.LPMCap is set, core responses with an ACK and the
+ * BESL value in the LPM token is less than or equal to LPM
+ * NYET threshold.
+ */
+ WARN_ONCE(dwc->revision < DWC3_REVISION_240A
+ && dwc->has_lpm_erratum,
+ "LPM Erratum not available on dwc3 revisisions < 2.40a\n");
+
+ if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
+ reg |= DWC3_DCTL_LPM_ERRATA(dwc->lpm_nyet_threshold);
+
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
} else {
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
@@ -25,5 +25,8 @@ struct dwc3_platform_data {
enum usb_dr_mode dr_mode;
bool tx_fifo_resize;
+ u8 lpm_nyet_threshold;
+
unsigned disable_scramble_quirk:1;
+ unsigned has_lpm_erratum:1;
};