[PATCH v4 06/20] usb: dwc3: add U2Exit LFPS quirk

From: Huang Rui
Date: Thu Oct 30 2014 - 06:10:49 EST


This patch adds U2Exit LFPS quirk, and some special platforms can configure
that if it is needed.

[ balbi@xxxxxx : added DeviceTree binding documentation ]

Signed-off-by: Huang Rui <ray.huang@xxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxx>
---
Documentation/devicetree/bindings/usb/dwc3.txt | 1 +
drivers/usb/dwc3/core.c | 6 ++++++
drivers/usb/dwc3/core.h | 3 +++
drivers/usb/dwc3/platform_data.h | 1 +
4 files changed, 11 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
index 2b0c1f2..79ed37c 100644
--- a/Documentation/devicetree/bindings/usb/dwc3.txt
+++ b/Documentation/devicetree/bindings/usb/dwc3.txt
@@ -18,6 +18,7 @@ Optional properties:
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
+ - snps,u2exit_lfps_quirk: set if we want to enable U2Exit LFPS quirk

This is usually a subnode to DWC3 glue to which it is connected.

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 2ac96e4..6d1f09f 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -470,6 +470,9 @@ static int dwc3_core_init(struct dwc3 *dwc)
else
reg &= ~DWC3_GCTL_DISSCRAMBLE;

+ if (dwc->u2exit_lfps_quirk)
+ reg |= DWC3_GCTL_U2EXIT_LFPS;
+
/*
* WORKAROUND: DWC3 revisions <1.90a have a bug
* where the device can fail to connect at SuperSpeed
@@ -726,6 +729,8 @@ static int dwc3_probe(struct platform_device *pdev)

dwc->disable_scramble_quirk = of_property_read_bool(node,
"snps,disable_scramble_quirk");
+ dwc->u2exit_lfps_quirk = of_property_read_bool(node,
+ "snps,u2exit_lfps_quirk");
} else if (pdata) {
dwc->maximum_speed = pdata->maximum_speed;
dwc->has_lpm_erratum = pdata->has_lpm_erratum;
@@ -736,6 +741,7 @@ static int dwc3_probe(struct platform_device *pdev)
dwc->dr_mode = pdata->dr_mode;

dwc->disable_scramble_quirk = pdata->disable_scramble_quirk;
+ dwc->u2exit_lfps_quirk = pdata->u2exit_lfps_quirk;
}

/* default to superspeed if no maximum_speed passed */
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 34f1e08..45130a1 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -166,6 +166,7 @@
#define DWC3_GCTL_SCALEDOWN(n) ((n) << 4)
#define DWC3_GCTL_SCALEDOWN_MASK DWC3_GCTL_SCALEDOWN(3)
#define DWC3_GCTL_DISSCRAMBLE (1 << 3)
+#define DWC3_GCTL_U2EXIT_LFPS (1 << 2)
#define DWC3_GCTL_GBLHIBERNATIONEN (1 << 1)
#define DWC3_GCTL_DSBLCLKGTNG (1 << 0)

@@ -679,6 +680,7 @@ struct dwc3_scratchpad_array {
* @start_config_issued: true when StartConfig command has been issued
* @three_stage_setup: set if we perform a three phase setup
* @disable_scramble_quirk: set if we enable the disable scramble quirk
+ * @u2exit_lfps_quirk: set if we enable U2Exit LFPS quirk
*/
struct dwc3 {
struct usb_ctrlrequest *ctrl_req;
@@ -787,6 +789,7 @@ struct dwc3 {
unsigned three_stage_setup:1;

unsigned disable_scramble_quirk:1;
+ unsigned u2exit_lfps_quirk:1;
};

/* -------------------------------------------------------------------------- */
diff --git a/drivers/usb/dwc3/platform_data.h b/drivers/usb/dwc3/platform_data.h
index e128308..3f21591 100644
--- a/drivers/usb/dwc3/platform_data.h
+++ b/drivers/usb/dwc3/platform_data.h
@@ -29,4 +29,5 @@ struct dwc3_platform_data {

unsigned disable_scramble_quirk:1;
unsigned has_lpm_erratum:1;
+ unsigned u2exit_lfps_quirk:1;
};
--
1.9.1

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