usb: dwc3: add request p1p2p3 quirk

This patch adds request P1/P2/P3 quirk for U2/U2/U3, and some special
platforms can configure that if it is needed.

[ balbi@ti.com : added DeviceTree binding documentation ]

Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Documentation/devicetree/bindings/usb/dwc3.txt

@@ -20,6 +20,8 @@ Optional properties:
  - snps,lpm-nyet-threshold: LPM NYET threshold
  - snps,u2exit_lfps_quirk: set if we want to enable u2exit lfps quirk
  - snps,u2ss_inp3_quirk: set if we enable P3 OK for U2/SS Inactive quirk
+ - snps,req_p1p2p3_quirk: when set, the core will always request for
+			P1/P2/P3 transition sequence.
 
 This is usually a subnode to DWC3 glue to which it is connected.
 

drivers/usb/dwc3/core.c

@@ -377,6 +377,9 @@ static void dwc3_phy_setup(struct dwc3 *dwc)
 	if (dwc->u2ss_inp3_quirk)
 		reg |= DWC3_GUSB3PIPECTL_U2SSINP3OK;
 
+	if (dwc->req_p1p2p3_quirk)
+		reg |= DWC3_GUSB3PIPECTL_REQP1P2P3;
+
 	dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);
 
 	mdelay(100);
@@ -756,6 +759,8 @@ static int dwc3_probe(struct platform_device *pdev)
 				"snps,u2exit_lfps_quirk");
 		dwc->u2ss_inp3_quirk = of_property_read_bool(node,
 				"snps,u2ss_inp3_quirk");
+		dwc->req_p1p2p3_quirk = of_property_read_bool(node,
+				"snps,req_p1p2p3_quirk");
 	} else if (pdata) {
 		dwc->maximum_speed = pdata->maximum_speed;
 		dwc->has_lpm_erratum = pdata->has_lpm_erratum;
@@ -768,6 +773,7 @@ static int dwc3_probe(struct platform_device *pdev)
 		dwc->disable_scramble_quirk = pdata->disable_scramble_quirk;
 		dwc->u2exit_lfps_quirk = pdata->u2exit_lfps_quirk;
 		dwc->u2ss_inp3_quirk = pdata->u2ss_inp3_quirk;
+		dwc->req_p1p2p3_quirk = pdata->req_p1p2p3_quirk;
 	}
 
 	/* default to superspeed if no maximum_speed passed */

drivers/usb/dwc3/core.h

@@ -177,6 +177,7 @@
 /* Global USB3 PIPE Control Register */
 #define DWC3_GUSB3PIPECTL_PHYSOFTRST	(1 << 31)
 #define DWC3_GUSB3PIPECTL_U2SSINP3OK	(1 << 29)
+#define DWC3_GUSB3PIPECTL_REQP1P2P3	(1 << 24)
 #define DWC3_GUSB3PIPECTL_SUSPHY	(1 << 17)
 
 /* Global TX Fifo Size Register */
@@ -683,6 +684,7 @@ struct dwc3_scratchpad_array {
  * @disable_scramble_quirk: set if we enable the disable scramble quirk
  * @u2exit_lfps_quirk: set if we enable u2exit lfps quirk
  * @u2ss_inp3_quirk: set if we enable P3 OK for U2/SS Inactive quirk
+ * @req_p1p2p3_quirk: set if we enable request p1p2p3 quirk
  */
 struct dwc3 {
 	struct usb_ctrlrequest	*ctrl_req;
@@ -793,6 +795,7 @@ struct dwc3 {
 	unsigned		disable_scramble_quirk:1;
 	unsigned		u2exit_lfps_quirk:1;
 	unsigned		u2ss_inp3_quirk:1;
+	unsigned		req_p1p2p3_quirk:1;
 };
 
 /* -------------------------------------------------------------------------- */

drivers/usb/dwc3/platform_data.h

@@ -31,4 +31,5 @@ struct dwc3_platform_data {
 	unsigned has_lpm_erratum:1;
 	unsigned u2exit_lfps_quirk:1;
 	unsigned u2ss_inp3_quirk:1;
+	unsigned req_p1p2p3_quirk:1;
 };