[PATCH v4 0/2] Meson GXL USB3 PHY driver

[PATCH v4 0/2] Meson GXL USB3 PHY driver

[Martin Blumenstingl]

Amlogic Meson GXL SoCs use a dwc3 controller with two USB2 ports,
Meson GXM SoCs use the same dwc3 controller but with three USB3
ports enabled. Neither of these SoCs has any USB3 port enabled in
the dwc3 registers.
The second USB2 port on both SoCs supports host and peripheral
(also called "device") mode.

The dwc3 controller supports host mode only. Peripheral mode is
implemented through an additional dwc2 controller (which only enables
device mode). The USB3 PHY has register bits which allow a driver to
detect the current mode - however this is currently not implemented
as the dwc2 controller seems to hang during reset (and I do not have
a use-case where I need peripheral/device mode).

While the dwc3 controller has no USB3 port enabled we still need the
USB3 PHY to be initialized, otherwise some boards (probably those where
the bootloader does not initialize the USB3 PHY) show errors with
high-speed USB devices connected to any of the USB2 ports. Configuring
the USB_R1_U3H_FLADJ_30MHZ_REG_MASK register as it's done by Amlogic's
vendor GPL kernel sources makes these error go away.

Thanks to Jerome Brunet for reporting the errors and Neil Armstrong
for discovering that initializing the USB3 PHY fixes these USB errors!


changes since v3 at [2]:
- rebased on top of Kishon's linux-phy next branch (commit:
  1f846be367fba4 "phy: allwinner: sun4i-usb: poll vbus changes on
  A23/A33 when driving VBUS")
- use SPDX-License-Identifier instead of the full license text

changes since v2 at [1]:
- collected Rob's Reviewed-by on patch #1 and Yixun's Tested-by
- rebased on top of v4.16-rc1 (no changes were required though)

changes since v1 at [0]:
- document the interrupt in the dt-bindings patch (we don't use it in
  the driver yet, but this interrupt is there so it should be
  documented)
- added the clock and reset lines, thank to Yixun Lan who gave me the
  hints that these are needed (it's not clear when reading the Amlogic
  GPL kernel sources, because the clock for example is always enabled
  by hardware default, bootrom, etc..)
- implemented the .set_mode callback
- NOTE: I chose *NOT* to add Jerome's and Neil's Tested-by's as well as
  Rob's Acked-by on the dt-bindings patch since I made changes that I
  want to have reviewed again


[0] http://lists.infradead.org/pipermail/linux-amlogic/2017-September/004780.html
[1] http://lists.infradead.org/pipermail/linux-amlogic/2018-January/006290.html
[2] http://lists.infradead.org/pipermail/linux-amlogic/2018-February/006449.html

Martin Blumenstingl (2):
  dt-bindings: phy: Add support for the USB3 PHY on Amlogic Meson GXL
    SoCs
  phy: amlogic: add USB3 PHY support for Meson GXL and GXM

 .../devicetree/bindings/phy/meson-gxl-usb3-phy.txt |  31 +++
 drivers/phy/amlogic/Kconfig                        |  12 +
 drivers/phy/amlogic/Makefile                       |   1 +
 drivers/phy/amlogic/phy-meson-gxl-usb3.c           | 282 +++++++++++++++++++++
 4 files changed, 326 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
 create mode 100644 drivers/phy/amlogic/phy-meson-gxl-usb3.c

-- 
2.16.2

[PATCH v4 0/2] Meson GXL USB3 PHY driver

[Martin Blumenstingl]

Amlogic Meson GXL SoCs use a dwc3 controller with two USB2 ports,
Meson GXM SoCs use the same dwc3 controller but with three USB3
ports enabled. Neither of these SoCs has any USB3 port enabled in
the dwc3 registers.
The second USB2 port on both SoCs supports host and peripheral
(also called "device") mode.

The dwc3 controller supports host mode only. Peripheral mode is
implemented through an additional dwc2 controller (which only enables
device mode). The USB3 PHY has register bits which allow a driver to
detect the current mode - however this is currently not implemented
as the dwc2 controller seems to hang during reset (and I do not have
a use-case where I need peripheral/device mode).

While the dwc3 controller has no USB3 port enabled we still need the
USB3 PHY to be initialized, otherwise some boards (probably those where
the bootloader does not initialize the USB3 PHY) show errors with
high-speed USB devices connected to any of the USB2 ports. Configuring
the USB_R1_U3H_FLADJ_30MHZ_REG_MASK register as it's done by Amlogic's
vendor GPL kernel sources makes these error go away.

Thanks to Jerome Brunet for reporting the errors and Neil Armstrong
for discovering that initializing the USB3 PHY fixes these USB errors!


changes since v3 at [2]:
- rebased on top of Kishon's linux-phy next branch (commit:
  1f846be367fba4 "phy: allwinner: sun4i-usb: poll vbus changes on
  A23/A33 when driving VBUS")
- use SPDX-License-Identifier instead of the full license text

changes since v2 at [1]:
- collected Rob's Reviewed-by on patch #1 and Yixun's Tested-by
- rebased on top of v4.16-rc1 (no changes were required though)

changes since v1 at [0]:
- document the interrupt in the dt-bindings patch (we don't use it in
  the driver yet, but this interrupt is there so it should be
  documented)
- added the clock and reset lines, thank to Yixun Lan who gave me the
  hints that these are needed (it's not clear when reading the Amlogic
  GPL kernel sources, because the clock for example is always enabled
  by hardware default, bootrom, etc..)
- implemented the .set_mode callback
- NOTE: I chose *NOT* to add Jerome's and Neil's Tested-by's as well as
  Rob's Acked-by on the dt-bindings patch since I made changes that I
  want to have reviewed again


[0] http://lists.infradead.org/pipermail/linux-amlogic/2017-September/004780.html
[1] http://lists.infradead.org/pipermail/linux-amlogic/2018-January/006290.html
[2] http://lists.infradead.org/pipermail/linux-amlogic/2018-February/006449.html

Martin Blumenstingl (2):
  dt-bindings: phy: Add support for the USB3 PHY on Amlogic Meson GXL
    SoCs
  phy: amlogic: add USB3 PHY support for Meson GXL and GXM

 .../devicetree/bindings/phy/meson-gxl-usb3-phy.txt |  31 +++
 drivers/phy/amlogic/Kconfig                        |  12 +
 drivers/phy/amlogic/Makefile                       |   1 +
 drivers/phy/amlogic/phy-meson-gxl-usb3.c           | 282 +++++++++++++++++++++
 4 files changed, 326 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
 create mode 100644 drivers/phy/amlogic/phy-meson-gxl-usb3.c

-- 
2.16.2

[PATCH v4 1/2] dt-bindings: phy: Add support for the USB3 PHY on Amlogic Meson GXL SoCs

[Martin Blumenstingl]

Amlogic Meson GXL SoCs use a dwc3 controller with two (GXM - a variant
for GXL, has three) USB2 ports. The first USB2 port supports host and
peripheral (also called "device") mode.
While the dwc3 controller has no USB3 port enabled we still need the
USB3 PHY to be initialized. Otherwise high-speed USB transfers (for
example with a USB flash drive) may time out (most often seen on boards
with mainline u-boot, where the bootloader does not initialize the USB3
PHY registers).

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Tested-by: Yixun Lan <yixun.lan@amlogic.com>
---
 .../devicetree/bindings/phy/meson-gxl-usb3-phy.txt | 31 ++++++++++++++++++++++
 1 file changed, 31 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt

diff --git a/Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt b/Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
new file mode 100644
index 000000000000..114947e1de3d
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
@@ -0,0 +1,31 @@
+* Amlogic Meson GXL and GXM USB3 PHY and OTG detection binding
+
+Required properties:
+- compatible:	Should be "amlogic,meson-gxl-usb3-phy"
+- #phys-cells:	must be 0 (see phy-bindings.txt in this directory)
+- reg:		The base address and length of the registers
+- interrupts:	the interrupt specifier for the OTG detection
+- clocks:	phandles to the clocks for
+		- the USB3 PHY
+		- and peripheral mode/OTG detection
+- clock-names:	must contain "phy" and "peripheral"
+- resets:	phandle to the reset lines for:
+		- the USB3 PHY and
+		- peripheral mode/OTG detection
+- reset-names:	must contain "phy" and "peripheral"
+
+Optional properties:
+- phy-supply:	see phy-bindings.txt in this directory
+
+
+Example:
+	usb3_phy0: phy@78080 {
+		compatible = "amlogic,meson-gxl-usb3-phy";
+		#phy-cells = <0>;
+		reg = <0x0 0x78080 0x0 0x20>;
+		interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&clkc CLKID_USB_OTG>, <&clkc_AO CLKID_AO_CEC_32K>;
+		clock-names = "phy", "peripheral";
+		resets = <&reset RESET_USB_OTG>, <&reset RESET_USB_OTG>;
+		reset-names = "phy", "peripheral";
+	};
-- 
2.16.2

[PATCH v4 1/2] dt-bindings: phy: Add support for the USB3 PHY on Amlogic Meson GXL SoCs

[Martin Blumenstingl]

Amlogic Meson GXL SoCs use a dwc3 controller with two (GXM - a variant
for GXL, has three) USB2 ports. The first USB2 port supports host and
peripheral (also called "device") mode.
While the dwc3 controller has no USB3 port enabled we still need the
USB3 PHY to be initialized. Otherwise high-speed USB transfers (for
example with a USB flash drive) may time out (most often seen on boards
with mainline u-boot, where the bootloader does not initialize the USB3
PHY registers).

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Tested-by: Yixun Lan <yixun.lan@amlogic.com>
---
 .../devicetree/bindings/phy/meson-gxl-usb3-phy.txt | 31 ++++++++++++++++++++++
 1 file changed, 31 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt

diff --git a/Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt b/Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
new file mode 100644
index 000000000000..114947e1de3d
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
@@ -0,0 +1,31 @@
+* Amlogic Meson GXL and GXM USB3 PHY and OTG detection binding
+
+Required properties:
+- compatible:	Should be "amlogic,meson-gxl-usb3-phy"
+- #phys-cells:	must be 0 (see phy-bindings.txt in this directory)
+- reg:		The base address and length of the registers
+- interrupts:	the interrupt specifier for the OTG detection
+- clocks:	phandles to the clocks for
+		- the USB3 PHY
+		- and peripheral mode/OTG detection
+- clock-names:	must contain "phy" and "peripheral"
+- resets:	phandle to the reset lines for:
+		- the USB3 PHY and
+		- peripheral mode/OTG detection
+- reset-names:	must contain "phy" and "peripheral"
+
+Optional properties:
+- phy-supply:	see phy-bindings.txt in this directory
+
+
+Example:
+	usb3_phy0: phy at 78080 {
+		compatible = "amlogic,meson-gxl-usb3-phy";
+		#phy-cells = <0>;
+		reg = <0x0 0x78080 0x0 0x20>;
+		interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&clkc CLKID_USB_OTG>, <&clkc_AO CLKID_AO_CEC_32K>;
+		clock-names = "phy", "peripheral";
+		resets = <&reset RESET_USB_OTG>, <&reset RESET_USB_OTG>;
+		reset-names = "phy", "peripheral";
+	};
-- 
2.16.2

[PATCH v4 2/2] phy: amlogic: add USB3 PHY support for Meson GXL and GXM

[Martin Blumenstingl]

This adds a new driver for the USB3 PHY found on Meson GXL and GXM SoCs
(both SoCs are using the same USB PHY register layout).

Unfortunately there is no documentation for this PHY in the public S905X
datasheet (published for example by Khadas). What we know so far about
this PHY:
- even though the Meson GXL and GXM SoCs do not expose an USB3 port (the
  dwc3 controller only has USB2 ports enabled) we need to initialize the
  USB3 PHY (specifically USB_R1_U3H_FLADJ_30MHZ_REG_MASK). Without this
  initialization high-speed USB devices (especially USB hard disks and
  thumb drives, slower devices like mice do not seem to be affected)
- on some boards the USB3 PHY starts in "device mode" - we want to bring
  it into a known state (by switching it to host mode for now).
- it is responsible for the OTG detection and for switching the first
  USB2 PHY between host and peripheral (aka device) mode. an interrupt
  can be used to detect changes between host and device mode.

There are five inputs to this register area:
- the clock and reset line for the USB3 PHY itself
- the clock and reset line for the peripheral mode and OTG detection
  logic (on the GXL and GXM SoCs these are the same clock and reset line
  as for the USB3 PHY itself, but Amlogic sees this as two different
  components - even though they share the same register space - so they
  have to be passed individually to allow specifying different inputs on
  other SoCs if needed)
- the interrupt for the OTG detection logic

The whole OTG detection logic is not implemented yet.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Yixun Lan <yixun.lan@amlogic.com>
---
 drivers/phy/amlogic/Kconfig              |  12 ++
 drivers/phy/amlogic/Makefile             |   1 +
 drivers/phy/amlogic/phy-meson-gxl-usb3.c | 282 +++++++++++++++++++++++++++++++
 3 files changed, 295 insertions(+)
 create mode 100644 drivers/phy/amlogic/phy-meson-gxl-usb3.c

diff --git a/drivers/phy/amlogic/Kconfig b/drivers/phy/amlogic/Kconfig
index ef3625cd25bb..23fe1cda2f70 100644
--- a/drivers/phy/amlogic/Kconfig
+++ b/drivers/phy/amlogic/Kconfig
@@ -24,3 +24,15 @@ config PHY_MESON_GXL_USB2
 	  Enable this to support the Meson USB2 PHYs found in Meson
 	  GXL and GXM SoCs.
 	  If unsure, say N.
+
+config PHY_MESON_GXL_USB3
+	tristate "Meson GXL and GXM USB3 PHY drivers"
+	default ARCH_MESON
+	depends on OF && (ARCH_MESON || COMPILE_TEST)
+	depends on USB_SUPPORT
+	select GENERIC_PHY
+	select REGMAP_MMIO
+	help
+	  Enable this to support the Meson USB3 PHY and OTG detection
+	  IP block found in Meson GXL and GXM SoCs.
+	  If unsure, say N.
diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
index cfdc98715c30..4fd8848c194d 100644
--- a/drivers/phy/amlogic/Makefile
+++ b/drivers/phy/amlogic/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_PHY_MESON8B_USB2)		+= phy-meson8b-usb2.o
 obj-$(CONFIG_PHY_MESON_GXL_USB2)	+= phy-meson-gxl-usb2.o
+obj-$(CONFIG_PHY_MESON_GXL_USB3)	+= phy-meson-gxl-usb3.o
diff --git a/drivers/phy/amlogic/phy-meson-gxl-usb3.c b/drivers/phy/amlogic/phy-meson-gxl-usb3.c
new file mode 100644
index 000000000000..d37d94ddf9c0
--- /dev/null
+++ b/drivers/phy/amlogic/phy-meson-gxl-usb3.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Meson GXL USB3 PHY and OTG mode detection driver
+ *
+ * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/platform_device.h>
+
+#define USB_R0							0x00
+	#define USB_R0_P30_FSEL_MASK				GENMASK(5, 0)
+	#define USB_R0_P30_PHY_RESET				BIT(6)
+	#define USB_R0_P30_TEST_POWERDOWN_HSP			BIT(7)
+	#define USB_R0_P30_TEST_POWERDOWN_SSP			BIT(8)
+	#define USB_R0_P30_ACJT_LEVEL_MASK			GENMASK(13, 9)
+	#define USB_R0_P30_TX_BOOST_LEVEL_MASK			GENMASK(16, 14)
+	#define USB_R0_P30_LANE0_TX2RX_LOOPBACK			BIT(17)
+	#define USB_R0_P30_LANE0_EXT_PCLK_REQ			BIT(18)
+	#define USB_R0_P30_PCS_RX_LOS_MASK_VAL_MASK		GENMASK(28, 19)
+	#define USB_R0_U2D_SS_SCALEDOWN_MODE_MASK		GENMASK(30, 29)
+	#define USB_R0_U2D_ACT					BIT(31)
+
+#define USB_R1							0x04
+	#define USB_R1_U3H_BIGENDIAN_GS				BIT(0)
+	#define USB_R1_U3H_PME_ENABLE				BIT(1)
+	#define USB_R1_U3H_HUB_PORT_OVERCURRENT_MASK		GENMASK(6, 2)
+	#define USB_R1_U3H_HUB_PORT_PERM_ATTACH_MASK		GENMASK(11, 7)
+	#define USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK		GENMASK(15, 12)
+	#define USB_R1_U3H_HOST_U3_PORT_DISABLE			BIT(16)
+	#define USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT	BIT(17)
+	#define USB_R1_U3H_HOST_MSI_ENABLE			BIT(18)
+	#define USB_R1_U3H_FLADJ_30MHZ_REG_MASK			GENMASK(24, 19)
+	#define USB_R1_P30_PCS_TX_SWING_FULL_MASK		GENMASK(31, 25)
+
+#define USB_R2							0x08
+	#define USB_R2_P30_CR_DATA_IN_MASK			GENMASK(15, 0)
+	#define USB_R2_P30_CR_READ				BIT(16)
+	#define USB_R2_P30_CR_WRITE				BIT(17)
+	#define USB_R2_P30_CR_CAP_ADDR				BIT(18)
+	#define USB_R2_P30_CR_CAP_DATA				BIT(19)
+	#define USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK		GENMASK(25, 20)
+	#define USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK		GENMASK(31, 26)
+
+#define USB_R3							0x0c
+	#define USB_R3_P30_SSC_ENABLE				BIT(0)
+	#define USB_R3_P30_SSC_RANGE_MASK			GENMASK(3, 1)
+	#define USB_R3_P30_SSC_REF_CLK_SEL_MASK			GENMASK(12, 4)
+	#define USB_R3_P30_REF_SSP_EN				BIT(13)
+	#define USB_R3_P30_LOS_BIAS_MASK			GENMASK(18, 16)
+	#define USB_R3_P30_LOS_LEVEL_MASK			GENMASK(23, 19)
+	#define USB_R3_P30_MPLL_MULTIPLIER_MASK			GENMASK(30, 24)
+
+#define USB_R4							0x10
+	#define USB_R4_P21_PORT_RESET_0				BIT(0)
+	#define USB_R4_P21_SLEEP_M0				BIT(1)
+	#define USB_R4_MEM_PD_MASK				GENMASK(3, 2)
+	#define USB_R4_P21_ONLY					BIT(4)
+
+#define USB_R5							0x14
+	#define USB_R5_ID_DIG_SYNC				BIT(0)
+	#define USB_R5_ID_DIG_REG				BIT(1)
+	#define USB_R5_ID_DIG_CFG_MASK				GENMASK(3, 2)
+	#define USB_R5_ID_DIG_EN_0				BIT(4)
+	#define USB_R5_ID_DIG_EN_1				BIT(5)
+	#define USB_R5_ID_DIG_CURR				BIT(6)
+	#define USB_R5_ID_DIG_IRQ				BIT(7)
+	#define USB_R5_ID_DIG_TH_MASK				GENMASK(15, 8)
+	#define USB_R5_ID_DIG_CNT_MASK				GENMASK(23, 16)
+
+/* read-only register */
+#define USB_R6							0x18
+	#define USB_R6_P30_CR_DATA_OUT_MASK			GENMASK(15, 0)
+	#define USB_R6_P30_CR_ACK				BIT(16)
+
+struct phy_meson_gxl_usb3_priv {
+	struct regmap		*regmap;
+	enum phy_mode		mode;
+	struct clk		*clk_phy;
+	struct clk		*clk_peripheral;
+	struct reset_control	*reset;
+};
+
+static const struct regmap_config phy_meson_gxl_usb3_regmap_conf = {
+	.reg_bits = 8,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = USB_R6,
+};
+
+static int phy_meson_gxl_usb3_power_on(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_0,
+			   USB_R5_ID_DIG_EN_0);
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_1,
+			   USB_R5_ID_DIG_EN_1);
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_TH_MASK,
+			   FIELD_PREP(USB_R5_ID_DIG_TH_MASK, 0xff));
+
+	return 0;
+}
+
+static int phy_meson_gxl_usb3_power_off(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_0, 0);
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_1, 0);
+
+	return 0;
+}
+
+static int phy_meson_gxl_usb3_set_mode(struct phy *phy, enum phy_mode mode)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	switch (mode) {
+	case PHY_MODE_USB_HOST:
+		regmap_update_bits(priv->regmap, USB_R0, USB_R0_U2D_ACT, 0);
+		regmap_update_bits(priv->regmap, USB_R4, USB_R4_P21_SLEEP_M0,
+				   0);
+		break;
+
+	case PHY_MODE_USB_DEVICE:
+		regmap_update_bits(priv->regmap, USB_R0, USB_R0_U2D_ACT,
+				   USB_R0_U2D_ACT);
+		regmap_update_bits(priv->regmap, USB_R4, USB_R4_P21_SLEEP_M0,
+				   USB_R4_P21_SLEEP_M0);
+		break;
+
+	default:
+		dev_err(&phy->dev, "unsupported PHY mode %d\n", mode);
+		return -EINVAL;
+	}
+
+	priv->mode = mode;
+
+	return 0;
+}
+
+static int phy_meson_gxl_usb3_init(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+	int ret;
+
+	ret = reset_control_reset(priv->reset);
+	if (ret)
+		goto err;
+
+	ret = clk_prepare_enable(priv->clk_phy);
+	if (ret)
+		goto err;
+
+	ret = clk_prepare_enable(priv->clk_peripheral);
+	if (ret)
+		goto err_disable_clk_phy;
+
+	ret = phy_meson_gxl_usb3_set_mode(phy, priv->mode);
+	if (ret)
+		goto err_disable_clk_peripheral;
+
+	regmap_update_bits(priv->regmap, USB_R1,
+			   USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
+			   FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));
+
+	return 0;
+
+err_disable_clk_peripheral:
+	clk_disable_unprepare(priv->clk_peripheral);
+err_disable_clk_phy:
+	clk_disable_unprepare(priv->clk_phy);
+err:
+	return ret;
+}
+
+static int phy_meson_gxl_usb3_exit(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	clk_disable_unprepare(priv->clk_peripheral);
+	clk_disable_unprepare(priv->clk_phy);
+
+	return 0;
+}
+
+static const struct phy_ops phy_meson_gxl_usb3_ops = {
+	.power_on	= phy_meson_gxl_usb3_power_on,
+	.power_off	= phy_meson_gxl_usb3_power_off,
+	.set_mode	= phy_meson_gxl_usb3_set_mode,
+	.init		= phy_meson_gxl_usb3_init,
+	.exit		= phy_meson_gxl_usb3_exit,
+	.owner		= THIS_MODULE,
+};
+
+static int phy_meson_gxl_usb3_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct phy_meson_gxl_usb3_priv *priv;
+	struct resource *res;
+	struct phy *phy;
+	struct phy_provider *phy_provider;
+	void __iomem *base;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	priv->regmap = devm_regmap_init_mmio(dev, base,
+					     &phy_meson_gxl_usb3_regmap_conf);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	priv->clk_phy = devm_clk_get(dev, "phy");
+	if (IS_ERR(priv->clk_phy))
+		return PTR_ERR(priv->clk_phy);
+
+	priv->clk_peripheral = devm_clk_get(dev, "peripheral");
+	if (IS_ERR(priv->clk_peripheral))
+		return PTR_ERR(priv->clk_peripheral);
+
+	priv->reset = devm_reset_control_array_get_shared(dev);
+	if (IS_ERR(priv->reset))
+		return PTR_ERR(priv->reset);
+
+	/*
+	 * default to host mode as hardware defaults and/or boot-loader
+	 * behavior can result in this PHY starting up in device mode. this
+	 * default and the initialization in phy_meson_gxl_usb3_init ensure
+	 * that we reproducibly start in a known mode on all devices.
+	 */
+	priv->mode = PHY_MODE_USB_HOST;
+
+	phy = devm_phy_create(dev, np, &phy_meson_gxl_usb3_ops);
+	if (IS_ERR(phy)) {
+		ret = PTR_ERR(phy);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "failed to create PHY\n");
+
+		return ret;
+	}
+
+	phy_set_drvdata(phy, priv);
+
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id phy_meson_gxl_usb3_of_match[] = {
+	{ .compatible = "amlogic,meson-gxl-usb3-phy", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, phy_meson_gxl_usb3_of_match);
+
+static struct platform_driver phy_meson_gxl_usb3_driver = {
+	.probe	= phy_meson_gxl_usb3_probe,
+	.driver	= {
+		.name		= "phy-meson-gxl-usb3",
+		.of_match_table	= phy_meson_gxl_usb3_of_match,
+	},
+};
+module_platform_driver(phy_meson_gxl_usb3_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Meson GXL USB3 PHY and OTG detection driver");
+MODULE_LICENSE("GPL v2");
-- 
2.16.2

[PATCH v4 2/2] phy: amlogic: add USB3 PHY support for Meson GXL and GXM

[Martin Blumenstingl]

This adds a new driver for the USB3 PHY found on Meson GXL and GXM SoCs
(both SoCs are using the same USB PHY register layout).

Unfortunately there is no documentation for this PHY in the public S905X
datasheet (published for example by Khadas). What we know so far about
this PHY:
- even though the Meson GXL and GXM SoCs do not expose an USB3 port (the
  dwc3 controller only has USB2 ports enabled) we need to initialize the
  USB3 PHY (specifically USB_R1_U3H_FLADJ_30MHZ_REG_MASK). Without this
  initialization high-speed USB devices (especially USB hard disks and
  thumb drives, slower devices like mice do not seem to be affected)
- on some boards the USB3 PHY starts in "device mode" - we want to bring
  it into a known state (by switching it to host mode for now).
- it is responsible for the OTG detection and for switching the first
  USB2 PHY between host and peripheral (aka device) mode. an interrupt
  can be used to detect changes between host and device mode.

There are five inputs to this register area:
- the clock and reset line for the USB3 PHY itself
- the clock and reset line for the peripheral mode and OTG detection
  logic (on the GXL and GXM SoCs these are the same clock and reset line
  as for the USB3 PHY itself, but Amlogic sees this as two different
  components - even though they share the same register space - so they
  have to be passed individually to allow specifying different inputs on
  other SoCs if needed)
- the interrupt for the OTG detection logic

The whole OTG detection logic is not implemented yet.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Yixun Lan <yixun.lan@amlogic.com>
---
 drivers/phy/amlogic/Kconfig              |  12 ++
 drivers/phy/amlogic/Makefile             |   1 +
 drivers/phy/amlogic/phy-meson-gxl-usb3.c | 282 +++++++++++++++++++++++++++++++
 3 files changed, 295 insertions(+)
 create mode 100644 drivers/phy/amlogic/phy-meson-gxl-usb3.c

diff --git a/drivers/phy/amlogic/Kconfig b/drivers/phy/amlogic/Kconfig
index ef3625cd25bb..23fe1cda2f70 100644
--- a/drivers/phy/amlogic/Kconfig
+++ b/drivers/phy/amlogic/Kconfig
@@ -24,3 +24,15 @@ config PHY_MESON_GXL_USB2
 	  Enable this to support the Meson USB2 PHYs found in Meson
 	  GXL and GXM SoCs.
 	  If unsure, say N.
+
+config PHY_MESON_GXL_USB3
+	tristate "Meson GXL and GXM USB3 PHY drivers"
+	default ARCH_MESON
+	depends on OF && (ARCH_MESON || COMPILE_TEST)
+	depends on USB_SUPPORT
+	select GENERIC_PHY
+	select REGMAP_MMIO
+	help
+	  Enable this to support the Meson USB3 PHY and OTG detection
+	  IP block found in Meson GXL and GXM SoCs.
+	  If unsure, say N.
diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
index cfdc98715c30..4fd8848c194d 100644
--- a/drivers/phy/amlogic/Makefile
+++ b/drivers/phy/amlogic/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_PHY_MESON8B_USB2)		+= phy-meson8b-usb2.o
 obj-$(CONFIG_PHY_MESON_GXL_USB2)	+= phy-meson-gxl-usb2.o
+obj-$(CONFIG_PHY_MESON_GXL_USB3)	+= phy-meson-gxl-usb3.o
diff --git a/drivers/phy/amlogic/phy-meson-gxl-usb3.c b/drivers/phy/amlogic/phy-meson-gxl-usb3.c
new file mode 100644
index 000000000000..d37d94ddf9c0
--- /dev/null
+++ b/drivers/phy/amlogic/phy-meson-gxl-usb3.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Meson GXL USB3 PHY and OTG mode detection driver
+ *
+ * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/platform_device.h>
+
+#define USB_R0							0x00
+	#define USB_R0_P30_FSEL_MASK				GENMASK(5, 0)
+	#define USB_R0_P30_PHY_RESET				BIT(6)
+	#define USB_R0_P30_TEST_POWERDOWN_HSP			BIT(7)
+	#define USB_R0_P30_TEST_POWERDOWN_SSP			BIT(8)
+	#define USB_R0_P30_ACJT_LEVEL_MASK			GENMASK(13, 9)
+	#define USB_R0_P30_TX_BOOST_LEVEL_MASK			GENMASK(16, 14)
+	#define USB_R0_P30_LANE0_TX2RX_LOOPBACK			BIT(17)
+	#define USB_R0_P30_LANE0_EXT_PCLK_REQ			BIT(18)
+	#define USB_R0_P30_PCS_RX_LOS_MASK_VAL_MASK		GENMASK(28, 19)
+	#define USB_R0_U2D_SS_SCALEDOWN_MODE_MASK		GENMASK(30, 29)
+	#define USB_R0_U2D_ACT					BIT(31)
+
+#define USB_R1							0x04
+	#define USB_R1_U3H_BIGENDIAN_GS				BIT(0)
+	#define USB_R1_U3H_PME_ENABLE				BIT(1)
+	#define USB_R1_U3H_HUB_PORT_OVERCURRENT_MASK		GENMASK(6, 2)
+	#define USB_R1_U3H_HUB_PORT_PERM_ATTACH_MASK		GENMASK(11, 7)
+	#define USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK		GENMASK(15, 12)
+	#define USB_R1_U3H_HOST_U3_PORT_DISABLE			BIT(16)
+	#define USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT	BIT(17)
+	#define USB_R1_U3H_HOST_MSI_ENABLE			BIT(18)
+	#define USB_R1_U3H_FLADJ_30MHZ_REG_MASK			GENMASK(24, 19)
+	#define USB_R1_P30_PCS_TX_SWING_FULL_MASK		GENMASK(31, 25)
+
+#define USB_R2							0x08
+	#define USB_R2_P30_CR_DATA_IN_MASK			GENMASK(15, 0)
+	#define USB_R2_P30_CR_READ				BIT(16)
+	#define USB_R2_P30_CR_WRITE				BIT(17)
+	#define USB_R2_P30_CR_CAP_ADDR				BIT(18)
+	#define USB_R2_P30_CR_CAP_DATA				BIT(19)
+	#define USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK		GENMASK(25, 20)
+	#define USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK		GENMASK(31, 26)
+
+#define USB_R3							0x0c
+	#define USB_R3_P30_SSC_ENABLE				BIT(0)
+	#define USB_R3_P30_SSC_RANGE_MASK			GENMASK(3, 1)
+	#define USB_R3_P30_SSC_REF_CLK_SEL_MASK			GENMASK(12, 4)
+	#define USB_R3_P30_REF_SSP_EN				BIT(13)
+	#define USB_R3_P30_LOS_BIAS_MASK			GENMASK(18, 16)
+	#define USB_R3_P30_LOS_LEVEL_MASK			GENMASK(23, 19)
+	#define USB_R3_P30_MPLL_MULTIPLIER_MASK			GENMASK(30, 24)
+
+#define USB_R4							0x10
+	#define USB_R4_P21_PORT_RESET_0				BIT(0)
+	#define USB_R4_P21_SLEEP_M0				BIT(1)
+	#define USB_R4_MEM_PD_MASK				GENMASK(3, 2)
+	#define USB_R4_P21_ONLY					BIT(4)
+
+#define USB_R5							0x14
+	#define USB_R5_ID_DIG_SYNC				BIT(0)
+	#define USB_R5_ID_DIG_REG				BIT(1)
+	#define USB_R5_ID_DIG_CFG_MASK				GENMASK(3, 2)
+	#define USB_R5_ID_DIG_EN_0				BIT(4)
+	#define USB_R5_ID_DIG_EN_1				BIT(5)
+	#define USB_R5_ID_DIG_CURR				BIT(6)
+	#define USB_R5_ID_DIG_IRQ				BIT(7)
+	#define USB_R5_ID_DIG_TH_MASK				GENMASK(15, 8)
+	#define USB_R5_ID_DIG_CNT_MASK				GENMASK(23, 16)
+
+/* read-only register */
+#define USB_R6							0x18
+	#define USB_R6_P30_CR_DATA_OUT_MASK			GENMASK(15, 0)
+	#define USB_R6_P30_CR_ACK				BIT(16)
+
+struct phy_meson_gxl_usb3_priv {
+	struct regmap		*regmap;
+	enum phy_mode		mode;
+	struct clk		*clk_phy;
+	struct clk		*clk_peripheral;
+	struct reset_control	*reset;
+};
+
+static const struct regmap_config phy_meson_gxl_usb3_regmap_conf = {
+	.reg_bits = 8,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = USB_R6,
+};
+
+static int phy_meson_gxl_usb3_power_on(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_0,
+			   USB_R5_ID_DIG_EN_0);
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_1,
+			   USB_R5_ID_DIG_EN_1);
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_TH_MASK,
+			   FIELD_PREP(USB_R5_ID_DIG_TH_MASK, 0xff));
+
+	return 0;
+}
+
+static int phy_meson_gxl_usb3_power_off(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_0, 0);
+	regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_1, 0);
+
+	return 0;
+}
+
+static int phy_meson_gxl_usb3_set_mode(struct phy *phy, enum phy_mode mode)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	switch (mode) {
+	case PHY_MODE_USB_HOST:
+		regmap_update_bits(priv->regmap, USB_R0, USB_R0_U2D_ACT, 0);
+		regmap_update_bits(priv->regmap, USB_R4, USB_R4_P21_SLEEP_M0,
+				   0);
+		break;
+
+	case PHY_MODE_USB_DEVICE:
+		regmap_update_bits(priv->regmap, USB_R0, USB_R0_U2D_ACT,
+				   USB_R0_U2D_ACT);
+		regmap_update_bits(priv->regmap, USB_R4, USB_R4_P21_SLEEP_M0,
+				   USB_R4_P21_SLEEP_M0);
+		break;
+
+	default:
+		dev_err(&phy->dev, "unsupported PHY mode %d\n", mode);
+		return -EINVAL;
+	}
+
+	priv->mode = mode;
+
+	return 0;
+}
+
+static int phy_meson_gxl_usb3_init(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+	int ret;
+
+	ret = reset_control_reset(priv->reset);
+	if (ret)
+		goto err;
+
+	ret = clk_prepare_enable(priv->clk_phy);
+	if (ret)
+		goto err;
+
+	ret = clk_prepare_enable(priv->clk_peripheral);
+	if (ret)
+		goto err_disable_clk_phy;
+
+	ret = phy_meson_gxl_usb3_set_mode(phy, priv->mode);
+	if (ret)
+		goto err_disable_clk_peripheral;
+
+	regmap_update_bits(priv->regmap, USB_R1,
+			   USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
+			   FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));
+
+	return 0;
+
+err_disable_clk_peripheral:
+	clk_disable_unprepare(priv->clk_peripheral);
+err_disable_clk_phy:
+	clk_disable_unprepare(priv->clk_phy);
+err:
+	return ret;
+}
+
+static int phy_meson_gxl_usb3_exit(struct phy *phy)
+{
+	struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+	clk_disable_unprepare(priv->clk_peripheral);
+	clk_disable_unprepare(priv->clk_phy);
+
+	return 0;
+}
+
+static const struct phy_ops phy_meson_gxl_usb3_ops = {
+	.power_on	= phy_meson_gxl_usb3_power_on,
+	.power_off	= phy_meson_gxl_usb3_power_off,
+	.set_mode	= phy_meson_gxl_usb3_set_mode,
+	.init		= phy_meson_gxl_usb3_init,
+	.exit		= phy_meson_gxl_usb3_exit,
+	.owner		= THIS_MODULE,
+};
+
+static int phy_meson_gxl_usb3_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct phy_meson_gxl_usb3_priv *priv;
+	struct resource *res;
+	struct phy *phy;
+	struct phy_provider *phy_provider;
+	void __iomem *base;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	priv->regmap = devm_regmap_init_mmio(dev, base,
+					     &phy_meson_gxl_usb3_regmap_conf);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	priv->clk_phy = devm_clk_get(dev, "phy");
+	if (IS_ERR(priv->clk_phy))
+		return PTR_ERR(priv->clk_phy);
+
+	priv->clk_peripheral = devm_clk_get(dev, "peripheral");
+	if (IS_ERR(priv->clk_peripheral))
+		return PTR_ERR(priv->clk_peripheral);
+
+	priv->reset = devm_reset_control_array_get_shared(dev);
+	if (IS_ERR(priv->reset))
+		return PTR_ERR(priv->reset);
+
+	/*
+	 * default to host mode as hardware defaults and/or boot-loader
+	 * behavior can result in this PHY starting up in device mode. this
+	 * default and the initialization in phy_meson_gxl_usb3_init ensure
+	 * that we reproducibly start in a known mode on all devices.
+	 */
+	priv->mode = PHY_MODE_USB_HOST;
+
+	phy = devm_phy_create(dev, np, &phy_meson_gxl_usb3_ops);
+	if (IS_ERR(phy)) {
+		ret = PTR_ERR(phy);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "failed to create PHY\n");
+
+		return ret;
+	}
+
+	phy_set_drvdata(phy, priv);
+
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id phy_meson_gxl_usb3_of_match[] = {
+	{ .compatible = "amlogic,meson-gxl-usb3-phy", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, phy_meson_gxl_usb3_of_match);
+
+static struct platform_driver phy_meson_gxl_usb3_driver = {
+	.probe	= phy_meson_gxl_usb3_probe,
+	.driver	= {
+		.name		= "phy-meson-gxl-usb3",
+		.of_match_table	= phy_meson_gxl_usb3_of_match,
+	},
+};
+module_platform_driver(phy_meson_gxl_usb3_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Meson GXL USB3 PHY and OTG detection driver");
+MODULE_LICENSE("GPL v2");
-- 
2.16.2

Re: [PATCH v4 0/2] Meson GXL USB3 PHY driver

[Neil Armstrong]

On 03/03/2018 19:46, Martin Blumenstingl wrote:
> Amlogic Meson GXL SoCs use a dwc3 controller with two USB2 ports,
> Meson GXM SoCs use the same dwc3 controller but with three USB3
> ports enabled. Neither of these SoCs has any USB3 port enabled in
> the dwc3 registers.
> The second USB2 port on both SoCs supports host and peripheral
> (also called "device") mode.
> 
> The dwc3 controller supports host mode only. Peripheral mode is
> implemented through an additional dwc2 controller (which only enables
> device mode). The USB3 PHY has register bits which allow a driver to
> detect the current mode - however this is currently not implemented
> as the dwc2 controller seems to hang during reset (and I do not have
> a use-case where I need peripheral/device mode).
> 
> While the dwc3 controller has no USB3 port enabled we still need the
> USB3 PHY to be initialized, otherwise some boards (probably those where
> the bootloader does not initialize the USB3 PHY) show errors with
> high-speed USB devices connected to any of the USB2 ports. Configuring
> the USB_R1_U3H_FLADJ_30MHZ_REG_MASK register as it's done by Amlogic's
> vendor GPL kernel sources makes these error go away.
> 
> Thanks to Jerome Brunet for reporting the errors and Neil Armstrong
> for discovering that initializing the USB3 PHY fixes these USB errors!
> 
> 
> changes since v3 at [2]:
> - rebased on top of Kishon's linux-phy next branch (commit:
>   1f846be367fba4 "phy: allwinner: sun4i-usb: poll vbus changes on
>   A23/A33 when driving VBUS")
> - use SPDX-License-Identifier instead of the full license text
> 
> changes since v2 at [1]:
> - collected Rob's Reviewed-by on patch #1 and Yixun's Tested-by
> - rebased on top of v4.16-rc1 (no changes were required though)
> 
> changes since v1 at [0]:
> - document the interrupt in the dt-bindings patch (we don't use it in
>   the driver yet, but this interrupt is there so it should be
>   documented)
> - added the clock and reset lines, thank to Yixun Lan who gave me the
>   hints that these are needed (it's not clear when reading the Amlogic
>   GPL kernel sources, because the clock for example is always enabled
>   by hardware default, bootrom, etc..)
> - implemented the .set_mode callback
> - NOTE: I chose *NOT* to add Jerome's and Neil's Tested-by's as well as
>   Rob's Acked-by on the dt-bindings patch since I made changes that I
>   want to have reviewed again
> 
> 
> [0] http://lists.infradead.org/pipermail/linux-amlogic/2017-September/004780.html
> [1] http://lists.infradead.org/pipermail/linux-amlogic/2018-January/006290.html
> [2] http://lists.infradead.org/pipermail/linux-amlogic/2018-February/006449.html
> 
> Martin Blumenstingl (2):
>   dt-bindings: phy: Add support for the USB3 PHY on Amlogic Meson GXL
>     SoCs
>   phy: amlogic: add USB3 PHY support for Meson GXL and GXM
> 
>  .../devicetree/bindings/phy/meson-gxl-usb3-phy.txt |  31 +++
>  drivers/phy/amlogic/Kconfig                        |  12 +
>  drivers/phy/amlogic/Makefile                       |   1 +
>  drivers/phy/amlogic/phy-meson-gxl-usb3.c           | 282 +++++++++++++++++++++
>  4 files changed, 326 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
>  create mode 100644 drivers/phy/amlogic/phy-meson-gxl-usb3.c
> 

Hi Martin, Kishon,

Successfully tested on Amlogic Q200 Reference Design board with a Meson GXM S912 SoC.

Other patchsets included :
- improvements and fixes for the phy-meson-gxl-usb2 driver https://lkml.kernel.org/r/20180128202245.25021-1-martin.blumenstingl@googlemail.com
- DWC3 support for Amlogic Meson AXG and GXL SoCs V2 https://lkml.kernel.org/r/20180211211517.5846-1-martin.blumenstingl@googlemail.com
- initialize (multiple) PHYs for a HCD V11 https://lkml.kernel.org/r/20180303214309.25643-1-martin.blumenstingl@googlemail.com

Tested-by: Neil Armstrong <narmstrong@baylibre.con>

Kishon, This driver has been around for a long time now, can you take for the next release ?

Thanks,
Neil

[PATCH v4 0/2] Meson GXL USB3 PHY driver

[Neil Armstrong]

On 03/03/2018 19:46, Martin Blumenstingl wrote:
> Amlogic Meson GXL SoCs use a dwc3 controller with two USB2 ports,
> Meson GXM SoCs use the same dwc3 controller but with three USB3
> ports enabled. Neither of these SoCs has any USB3 port enabled in
> the dwc3 registers.
> The second USB2 port on both SoCs supports host and peripheral
> (also called "device") mode.
> 
> The dwc3 controller supports host mode only. Peripheral mode is
> implemented through an additional dwc2 controller (which only enables
> device mode). The USB3 PHY has register bits which allow a driver to
> detect the current mode - however this is currently not implemented
> as the dwc2 controller seems to hang during reset (and I do not have
> a use-case where I need peripheral/device mode).
> 
> While the dwc3 controller has no USB3 port enabled we still need the
> USB3 PHY to be initialized, otherwise some boards (probably those where
> the bootloader does not initialize the USB3 PHY) show errors with
> high-speed USB devices connected to any of the USB2 ports. Configuring
> the USB_R1_U3H_FLADJ_30MHZ_REG_MASK register as it's done by Amlogic's
> vendor GPL kernel sources makes these error go away.
> 
> Thanks to Jerome Brunet for reporting the errors and Neil Armstrong
> for discovering that initializing the USB3 PHY fixes these USB errors!
> 
> 
> changes since v3 at [2]:
> - rebased on top of Kishon's linux-phy next branch (commit:
>   1f846be367fba4 "phy: allwinner: sun4i-usb: poll vbus changes on
>   A23/A33 when driving VBUS")
> - use SPDX-License-Identifier instead of the full license text
> 
> changes since v2 at [1]:
> - collected Rob's Reviewed-by on patch #1 and Yixun's Tested-by
> - rebased on top of v4.16-rc1 (no changes were required though)
> 
> changes since v1 at [0]:
> - document the interrupt in the dt-bindings patch (we don't use it in
>   the driver yet, but this interrupt is there so it should be
>   documented)
> - added the clock and reset lines, thank to Yixun Lan who gave me the
>   hints that these are needed (it's not clear when reading the Amlogic
>   GPL kernel sources, because the clock for example is always enabled
>   by hardware default, bootrom, etc..)
> - implemented the .set_mode callback
> - NOTE: I chose *NOT* to add Jerome's and Neil's Tested-by's as well as
>   Rob's Acked-by on the dt-bindings patch since I made changes that I
>   want to have reviewed again
> 
> 
> [0] http://lists.infradead.org/pipermail/linux-amlogic/2017-September/004780.html
> [1] http://lists.infradead.org/pipermail/linux-amlogic/2018-January/006290.html
> [2] http://lists.infradead.org/pipermail/linux-amlogic/2018-February/006449.html
> 
> Martin Blumenstingl (2):
>   dt-bindings: phy: Add support for the USB3 PHY on Amlogic Meson GXL
>     SoCs
>   phy: amlogic: add USB3 PHY support for Meson GXL and GXM
> 
>  .../devicetree/bindings/phy/meson-gxl-usb3-phy.txt |  31 +++
>  drivers/phy/amlogic/Kconfig                        |  12 +
>  drivers/phy/amlogic/Makefile                       |   1 +
>  drivers/phy/amlogic/phy-meson-gxl-usb3.c           | 282 +++++++++++++++++++++
>  4 files changed, 326 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/meson-gxl-usb3-phy.txt
>  create mode 100644 drivers/phy/amlogic/phy-meson-gxl-usb3.c
> 

Hi Martin, Kishon,

Successfully tested on Amlogic Q200 Reference Design board with a Meson GXM S912 SoC.

Other patchsets included :
- improvements and fixes for the phy-meson-gxl-usb2 driver https://lkml.kernel.org/r/20180128202245.25021-1-martin.blumenstingl at googlemail.com
- DWC3 support for Amlogic Meson AXG and GXL SoCs V2 https://lkml.kernel.org/r/20180211211517.5846-1-martin.blumenstingl at googlemail.com
- initialize (multiple) PHYs for a HCD V11 https://lkml.kernel.org/r/20180303214309.25643-1-martin.blumenstingl at googlemail.com

Tested-by: Neil Armstrong <narmstrong@baylibre.con>

Kishon, This driver has been around for a long time now, can you take for the next release ?

Thanks,
Neil