[PATCH 1/2] phy: qualcomm: add qcom dwc3 phy

From: Ansuel Smith <ansuelsmth@gmail.com>
To: Andy Gross <agross@kernel.org>
Cc: Ansuel Smith <ansuelsmth@gmail.com>,
	Andy Gross <agross@codeaurora.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Kishon Vijay Abraham I <kishon@ti.com>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
	devicetree@vger.kernel.org
Subject: [PATCH 1/2] phy: qualcomm: add qcom dwc3 phy
Date: Fri,  3 Apr 2020 02:26:04 +0200	[thread overview]
Message-ID: <20200403002608.946-1-ansuelsmth@gmail.com> (raw)

This has lost in the original push for the dwc3 qcom driver.
This is needed for ipq806x SoC as without this the usb ports
doesn't work at all.

Signed-off-by: Andy Gross <agross@codeaurora.org>
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
---
 drivers/phy/qualcomm/Kconfig         |  12 +
 drivers/phy/qualcomm/Makefile        |   1 +
 drivers/phy/qualcomm/phy-qcom-dwc3.c | 578 +++++++++++++++++++++++++++
 3 files changed, 591 insertions(+)
 create mode 100644 drivers/phy/qualcomm/phy-qcom-dwc3.c

diff --git a/drivers/phy/qualcomm/Kconfig b/drivers/phy/qualcomm/Kconfig
index e46824da29f6..3d45a9156f85 100644
--- a/drivers/phy/qualcomm/Kconfig
+++ b/drivers/phy/qualcomm/Kconfig
@@ -91,3 +91,15 @@ config PHY_QCOM_USB_HSIC
 	select GENERIC_PHY
 	help
 	  Support for the USB HSIC ULPI compliant PHY on QCOM chipsets.
+
+config PHY_QCOM_DWC3
+	tristate "QCOM DWC3 USB PHY support"
+	depends on ARCH_QCOM
+	depends on HAS_IOMEM
+	depends on OF
+	select GENERIC_PHY
+	help
+	  This option enables support for the Synopsis PHYs present inside the
+	  Qualcomm USB3.0 DWC3 controller.  This driver supports both HS and SS
+	  PHY controllers.
+
diff --git a/drivers/phy/qualcomm/Makefile b/drivers/phy/qualcomm/Makefile
index 283251d6a5d9..04c5a8da941a 100644
--- a/drivers/phy/qualcomm/Makefile
+++ b/drivers/phy/qualcomm/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_PHY_QCOM_UFS_14NM)		+= phy-qcom-ufs-qmp-14nm.o
 obj-$(CONFIG_PHY_QCOM_UFS_20NM)		+= phy-qcom-ufs-qmp-20nm.o
 obj-$(CONFIG_PHY_QCOM_USB_HS) 		+= phy-qcom-usb-hs.o
 obj-$(CONFIG_PHY_QCOM_USB_HSIC) 	+= phy-qcom-usb-hsic.o
+obj-$(CONFIG_PHY_QCOM_DWC3)		+= phy-qcom-dwc3.o
diff --git a/drivers/phy/qualcomm/phy-qcom-dwc3.c b/drivers/phy/qualcomm/phy-qcom-dwc3.c
new file mode 100644
index 000000000000..f33da199ddde
--- /dev/null
+++ b/drivers/phy/qualcomm/phy-qcom-dwc3.c
@@ -0,0 +1,578 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2014-2015, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+/* USB QSCRATCH Hardware registers */
+#define QSCRATCH_GENERAL_CFG		(0x08)
+#define HSUSB_PHY_CTRL_REG		(0x10)
+
+/* PHY_CTRL_REG */
+#define HSUSB_CTRL_DMSEHV_CLAMP			BIT(24)
+#define HSUSB_CTRL_USB2_SUSPEND			BIT(23)
+#define HSUSB_CTRL_UTMI_CLK_EN			BIT(21)
+#define HSUSB_CTRL_UTMI_OTG_VBUS_VALID		BIT(20)
+#define HSUSB_CTRL_USE_CLKCORE			BIT(18)
+#define HSUSB_CTRL_DPSEHV_CLAMP			BIT(17)
+#define HSUSB_CTRL_COMMONONN			BIT(11)
+#define HSUSB_CTRL_ID_HV_CLAMP			BIT(9)
+#define HSUSB_CTRL_OTGSESSVLD_CLAMP		BIT(8)
+#define HSUSB_CTRL_CLAMP_EN			BIT(7)
+#define HSUSB_CTRL_RETENABLEN			BIT(1)
+#define HSUSB_CTRL_POR				BIT(0)
+
+/* QSCRATCH_GENERAL_CFG */
+#define HSUSB_GCFG_XHCI_REV		BIT(2)
+
+/* USB QSCRATCH Hardware registers */
+#define SSUSB_PHY_CTRL_REG		(0x30)
+#define SSUSB_PHY_PARAM_CTRL_1		(0x34)
+#define SSUSB_PHY_PARAM_CTRL_2		(0x38)
+#define CR_PROTOCOL_DATA_IN_REG	(0x3c)
+#define CR_PROTOCOL_DATA_OUT_REG	(0x40)
+#define CR_PROTOCOL_CAP_ADDR_REG	(0x44)
+#define CR_PROTOCOL_CAP_DATA_REG	(0x48)
+#define CR_PROTOCOL_READ_REG		(0x4c)
+#define CR_PROTOCOL_WRITE_REG		(0x50)
+
+/* PHY_CTRL_REG */
+#define SSUSB_CTRL_REF_USE_PAD		BIT(28)
+#define SSUSB_CTRL_TEST_POWERDOWN	BIT(27)
+#define SSUSB_CTRL_LANE0_PWR_PRESENT	BIT(24)
+#define SSUSB_CTRL_SS_PHY_EN		BIT(8)
+#define SSUSB_CTRL_SS_PHY_RESET		BIT(7)
+
+/* SSPHY control registers - Does this need 0x30? */
+#define SSPHY_CTRL_RX_OVRD_IN_HI(lane)	(0x1006 + 0x100 * lane)
+#define SSPHY_CTRL_TX_OVRD_DRV_LO(lane)	(0x1002 + 0x100 * lane)
+
+/* SSPHY SoC version specific values */
+#define SSPHY_RX_EQ_VALUE		4 /* Override value for rx_eq */
+/* Override value for transmit preemphasis */
+#define SSPHY_TX_DEEMPH_3_5DB		23
+#define SSPHY_MPLL_VALUE		0 /* Override value for mpll */
+
+/* QSCRATCH PHY_PARAM_CTRL1 fields */
+#define PHY_PARAM_CTRL1_TX_FULL_SWING_MASK	0x07f00000u
+#define PHY_PARAM_CTRL1_TX_DEEMPH_6DB_MASK	0x000fc000u
+#define PHY_PARAM_CTRL1_TX_DEEMPH_3_5DB_MASK	0x00003f00u
+#define PHY_PARAM_CTRL1_LOS_BIAS_MASK		0x000000f8u
+
+#define PHY_PARAM_CTRL1_MASK				\
+		(PHY_PARAM_CTRL1_TX_FULL_SWING_MASK |	\
+		 PHY_PARAM_CTRL1_TX_DEEMPH_6DB_MASK |	\
+		 PHY_PARAM_CTRL1_TX_DEEMPH_3_5DB_MASK |	\
+		 PHY_PARAM_CTRL1_LOS_BIAS_MASK)
+
+#define PHY_PARAM_CTRL1_TX_FULL_SWING(x)	\
+		(((x) << 20) & PHY_PARAM_CTRL1_TX_FULL_SWING_MASK)
+#define PHY_PARAM_CTRL1_TX_DEEMPH_6DB(x)	\
+		(((x) << 14) & PHY_PARAM_CTRL1_TX_DEEMPH_6DB_MASK)
+#define PHY_PARAM_CTRL1_TX_DEEMPH_3_5DB(x)	\
+		(((x) <<  8) & PHY_PARAM_CTRL1_TX_DEEMPH_3_5DB_MASK)
+#define PHY_PARAM_CTRL1_LOS_BIAS(x)	\
+		(((x) <<  3) & PHY_PARAM_CTRL1_LOS_BIAS_MASK)
+
+/* RX OVRD IN HI bits */
+#define RX_OVRD_IN_HI_RX_RESET_OVRD		BIT(13)
+#define RX_OVRD_IN_HI_RX_RX_RESET		BIT(12)
+#define RX_OVRD_IN_HI_RX_EQ_OVRD		BIT(11)
+#define RX_OVRD_IN_HI_RX_EQ_MASK		0x0700
+#define RX_OVRD_IN_HI_RX_EQ_SHIFT		8
+#define RX_OVRD_IN_HI_RX_EQ_EN_OVRD		BIT(7)
+#define RX_OVRD_IN_HI_RX_EQ_EN			BIT(6)
+#define RX_OVRD_IN_HI_RX_LOS_FILTER_OVRD	BIT(5)
+#define RX_OVRD_IN_HI_RX_LOS_FILTER_MASK	0x0018
+#define RX_OVRD_IN_HI_RX_RATE_OVRD		BIT(2)
+#define RX_OVRD_IN_HI_RX_RATE_MASK		0x0003
+
+/* TX OVRD DRV LO register bits */
+#define TX_OVRD_DRV_LO_AMPLITUDE_MASK	0x007F
+#define TX_OVRD_DRV_LO_PREEMPH_MASK	0x3F80
+#define TX_OVRD_DRV_LO_PREEMPH_SHIFT	7
+#define TX_OVRD_DRV_LO_EN		BIT(14)
+
+/* SS CAP register bits */
+#define SS_CR_CAP_ADDR_REG		BIT(0)
+#define SS_CR_CAP_DATA_REG		BIT(0)
+#define SS_CR_READ_REG			BIT(0)
+#define SS_CR_WRITE_REG			BIT(0)
+
+struct qcom_dwc3_usb_phy {
+	struct regmap		*base;
+	struct device		*dev;
+	struct clk		*xo_clk;
+	struct clk		*ref_clk;
+	u32			rx_eq;
+	u32			tx_deamp_3_5db;
+	u32			mpll;
+};
+
+struct qcom_dwc3_phy_drvdata {
+	struct phy_ops	ops;
+	u32		clk_rate;
+};
+
+/**
+ * Write register and read back masked value to confirm it is written
+ *
+ * @base - QCOM DWC3 PHY base virtual address.
+ * @offset - register offset.
+ * @mask - register bitmask specifying what should be updated
+ * @val - value to write.
+ */
+static inline void qcom_dwc3_phy_write_readback(
+	struct qcom_dwc3_usb_phy *phy_dwc3, u32 offset,
+	const u32 mask, u32 val)
+{
+	u32 write_val, tmp;
+
+	tmp = regmap_read(phy_dwc3->base, offset, &tmp);
+	tmp &= ~mask;		/* retain other bits */
+	write_val = tmp | val;
+
+	regmap_write(phy_dwc3->base, offset, write_val);
+
+	/* Read back to see if val was written */
+	regmap_read(phy_dwc3->base, offset, &tmp);
+	tmp &= mask;		/* clear other bits */
+
+	if (tmp != val)
+		dev_err(phy_dwc3->dev, "write: %x to QSCRATCH: %x FAILED\n",
+			val, offset);
+}
+
+static int wait_for_latch(struct regmap *base, u32 addr)
+{
+	u32 retry = 10, data;
+
+	while (true) {
+		regmap_read(base, addr, &data);
+		if (!data)
+			break;
+
+		if (--retry == 0)
+			return -ETIMEDOUT;
+
+		usleep_range(10, 20);
+	}
+
+	return 0;
+}
+
+/**
+ * Write SSPHY register
+ *
+ * @base - QCOM DWC3 PHY base virtual address.
+ * @addr - SSPHY address to write.
+ * @val - value to write.
+ */
+static int qcom_dwc3_ss_write_phycreg(struct qcom_dwc3_usb_phy *phy_dwc3,
+					u32 addr, u32 val)
+{
+	int ret;
+
+	regmap_write(phy_dwc3->base, CR_PROTOCOL_DATA_IN_REG, addr);
+	regmap_write(phy_dwc3->base, CR_PROTOCOL_CAP_ADDR_REG,
+		     SS_CR_CAP_ADDR_REG);
+
+	ret = wait_for_latch(phy_dwc3->base, CR_PROTOCOL_CAP_ADDR_REG);
+	if (ret)
+		goto err_wait;
+
+	regmap_write(phy_dwc3->base, CR_PROTOCOL_DATA_IN_REG, val);
+	regmap_write(phy_dwc3->base, CR_PROTOCOL_CAP_DATA_REG,
+		     SS_CR_CAP_DATA_REG);
+
+	ret = wait_for_latch(phy_dwc3->base, CR_PROTOCOL_CAP_DATA_REG);
+	if (ret)
+		goto err_wait;
+
+	regmap_write(phy_dwc3->base, CR_PROTOCOL_WRITE_REG, SS_CR_WRITE_REG);
+
+	ret = wait_for_latch(phy_dwc3->base, CR_PROTOCOL_WRITE_REG);
+
+err_wait:
+	if (ret)
+		dev_err(phy_dwc3->dev, "timeout waiting for latch\n");
+	return ret;
+}
+
+/**
+ * Read SSPHY register.
+ *
+ * @base - QCOM DWC3 PHY base virtual address.
+ * @addr - SSPHY address to read.
+ */
+static int qcom_dwc3_ss_read_phycreg(struct regmap *base, u32 addr, u32 *val)
+{
+	int ret;
+
+	regmap_write(base, CR_PROTOCOL_DATA_IN_REG, addr);
+	regmap_write(base, CR_PROTOCOL_CAP_ADDR_REG, SS_CR_CAP_ADDR_REG);
+
+	ret = wait_for_latch(base, CR_PROTOCOL_CAP_ADDR_REG);
+	if (ret)
+		goto err_wait;
+
+	/*
+	 * Due to hardware bug, first read of SSPHY register might be
+	 * incorrect. Hence as workaround, SW should perform SSPHY register
+	 * read twice, but use only second read and ignore first read.
+	 */
+	regmap_write(base, CR_PROTOCOL_READ_REG, SS_CR_READ_REG);
+
+	ret = wait_for_latch(base, CR_PROTOCOL_READ_REG);
+	if (ret)
+		goto err_wait;
+
+	/* throwaway read */
+	regmap_read(base, CR_PROTOCOL_DATA_OUT_REG, &ret);
+
+	regmap_write(base, CR_PROTOCOL_READ_REG, SS_CR_READ_REG);
+
+	ret = wait_for_latch(base, CR_PROTOCOL_READ_REG);
+	if (ret)
+		goto err_wait;
+
+	regmap_read(base, CR_PROTOCOL_DATA_OUT_REG, val);
+
+err_wait:
+	return ret;
+}
+
+static int qcom_dwc3_hs_phy_init(struct phy *phy)
+{
+	struct qcom_dwc3_usb_phy *phy_dwc3 = phy_get_drvdata(phy);
+	int ret;
+	u32 val;
+
+	ret = clk_prepare_enable(phy_dwc3->xo_clk);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(phy_dwc3->ref_clk);
+	if (ret) {
+		clk_disable_unprepare(phy_dwc3->xo_clk);
+		return ret;
+	}
+
+	/*
+	 * HSPHY Initialization: Enable UTMI clock, select 19.2MHz fsel
+	 * enable clamping, and disable RETENTION (power-on default is ENABLED)
+	 */
+	val = HSUSB_CTRL_DPSEHV_CLAMP | HSUSB_CTRL_DMSEHV_CLAMP |
+		HSUSB_CTRL_RETENABLEN  | HSUSB_CTRL_COMMONONN |
+		HSUSB_CTRL_OTGSESSVLD_CLAMP | HSUSB_CTRL_ID_HV_CLAMP |
+		HSUSB_CTRL_DPSEHV_CLAMP | HSUSB_CTRL_UTMI_OTG_VBUS_VALID |
+		HSUSB_CTRL_UTMI_CLK_EN | HSUSB_CTRL_CLAMP_EN | 0x70;
+
+	/* use core clock if external reference is not present */
+	if (!phy_dwc3->xo_clk)
+		val |= HSUSB_CTRL_USE_CLKCORE;
+
+	regmap_write(phy_dwc3->base, HSUSB_PHY_CTRL_REG, val);
+	usleep_range(2000, 2200);
+
+	/* Disable (bypass) VBUS and ID filters */
+	regmap_write(phy_dwc3->base, QSCRATCH_GENERAL_CFG, HSUSB_GCFG_XHCI_REV);
+
+	return 0;
+}
+
+static int qcom_dwc3_hs_phy_exit(struct phy *phy)
+{
+	struct qcom_dwc3_usb_phy *phy_dwc3 = phy_get_drvdata(phy);
+
+	clk_disable_unprepare(phy_dwc3->ref_clk);
+	clk_disable_unprepare(phy_dwc3->xo_clk);
+
+	return 0;
+}
+
+static int qcom_dwc3_ss_phy_init(struct phy *phy)
+{
+	struct qcom_dwc3_usb_phy *phy_dwc3 = phy_get_drvdata(phy);
+	int ret;
+	u32 data = 0;
+
+	ret = clk_prepare_enable(phy_dwc3->xo_clk);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(phy_dwc3->ref_clk);
+	if (ret) {
+		clk_disable_unprepare(phy_dwc3->xo_clk);
+		return ret;
+	}
+
+	/* reset phy */
+	regmap_read(phy_dwc3->base, SSUSB_PHY_CTRL_REG, &data);
+	regmap_write(phy_dwc3->base, SSUSB_PHY_CTRL_REG,
+		data | SSUSB_CTRL_SS_PHY_RESET);
+	usleep_range(2000, 2200);
+	regmap_write(phy_dwc3->base, SSUSB_PHY_CTRL_REG, data);
+
+	/* clear REF_PAD if we don't have XO clk */
+	if (!phy_dwc3->xo_clk)
+		data &= ~SSUSB_CTRL_REF_USE_PAD;
+	else
+		data |= SSUSB_CTRL_REF_USE_PAD;
+
+	regmap_write(phy_dwc3->base, SSUSB_PHY_CTRL_REG, data);
+
+	/* wait for ref clk to become stable, this can take up to 30ms */
+	msleep(30);
+
+	data |= SSUSB_CTRL_SS_PHY_EN | SSUSB_CTRL_LANE0_PWR_PRESENT;
+	regmap_write(phy_dwc3->base, SSUSB_PHY_CTRL_REG, data);
+
+	/*
+	 * WORKAROUND: There is SSPHY suspend bug due to which USB enumerates
+	 * in HS mode instead of SS mode. Workaround it by asserting
+	 * LANE0.TX_ALT_BLOCK.EN_ALT_BUS to enable TX to use alt bus mode
+	 */
+	ret = qcom_dwc3_ss_read_phycreg(phy_dwc3->base, 0x102D, &data);
+	if (ret)
+		goto err_phy_trans;
+
+	data |= (1 << 7);
+	ret = qcom_dwc3_ss_write_phycreg(phy_dwc3, 0x102D, data);
+	if (ret)
+		goto err_phy_trans;
+
+	ret = qcom_dwc3_ss_read_phycreg(phy_dwc3->base, 0x1010, &data);
+	if (ret)
+		goto err_phy_trans;
+
+	data &= ~0xff0;
+	data |= 0x20;
+	ret = qcom_dwc3_ss_write_phycreg(phy_dwc3, 0x1010, data);
+	if (ret)
+		goto err_phy_trans;
+
+	/*
+	 * Fix RX Equalization setting as follows
+	 * LANE0.RX_OVRD_IN_HI. RX_EQ_EN set to 0
+	 * LANE0.RX_OVRD_IN_HI.RX_EQ_EN_OVRD set to 1
+	 * LANE0.RX_OVRD_IN_HI.RX_EQ set based on SoC version
+	 * LANE0.RX_OVRD_IN_HI.RX_EQ_OVRD set to 1
+	 */
+	ret = qcom_dwc3_ss_read_phycreg(phy_dwc3->base,
+			SSPHY_CTRL_RX_OVRD_IN_HI(0), &data);
+	if (ret)
+		goto err_phy_trans;
+
+	data &= ~RX_OVRD_IN_HI_RX_EQ_EN;
+	data |= RX_OVRD_IN_HI_RX_EQ_EN_OVRD;
+	data &= ~RX_OVRD_IN_HI_RX_EQ_MASK;
+	data |= phy_dwc3->rx_eq << RX_OVRD_IN_HI_RX_EQ_SHIFT;
+	data |= RX_OVRD_IN_HI_RX_EQ_OVRD;
+	ret = qcom_dwc3_ss_write_phycreg(phy_dwc3,
+		SSPHY_CTRL_RX_OVRD_IN_HI(0), data);
+	if (ret)
+		goto err_phy_trans;
+
+	/*
+	 * Set EQ and TX launch amplitudes as follows
+	 * LANE0.TX_OVRD_DRV_LO.PREEMPH set based on SoC version
+	 * LANE0.TX_OVRD_DRV_LO.AMPLITUDE set to 110
+	 * LANE0.TX_OVRD_DRV_LO.EN set to 1.
+	 */
+	ret = qcom_dwc3_ss_read_phycreg(phy_dwc3->base,
+		SSPHY_CTRL_TX_OVRD_DRV_LO(0), &data);
+	if (ret)
+		goto err_phy_trans;
+
+	data &= ~TX_OVRD_DRV_LO_PREEMPH_MASK;
+	data |= phy_dwc3->tx_deamp_3_5db << TX_OVRD_DRV_LO_PREEMPH_SHIFT;
+	data &= ~TX_OVRD_DRV_LO_AMPLITUDE_MASK;
+	data |= 0x6E;
+	data |= TX_OVRD_DRV_LO_EN;
+	ret = qcom_dwc3_ss_write_phycreg(phy_dwc3,
+		SSPHY_CTRL_TX_OVRD_DRV_LO(0), data);
+	if (ret)
+		goto err_phy_trans;
+
+	qcom_dwc3_ss_write_phycreg(phy_dwc3, 0x30, phy_dwc3->mpll);
+
+	/*
+	 * Set the QSCRATCH PHY_PARAM_CTRL1 parameters as follows
+	 * TX_FULL_SWING [26:20] amplitude to 110
+	 * TX_DEEMPH_6DB [19:14] to 32
+	 * TX_DEEMPH_3_5DB [13:8] set based on SoC version
+	 * LOS_BIAS [7:3] to 9
+	 */
+	regmap_read(phy_dwc3->base, SSUSB_PHY_PARAM_CTRL_1, &data);
+
+	data &= ~PHY_PARAM_CTRL1_MASK;
+
+	data |= PHY_PARAM_CTRL1_TX_FULL_SWING(0x6e) |
+		PHY_PARAM_CTRL1_TX_DEEMPH_6DB(0x20) |
+		PHY_PARAM_CTRL1_TX_DEEMPH_3_5DB(phy_dwc3->tx_deamp_3_5db) |
+		PHY_PARAM_CTRL1_LOS_BIAS(0x9);
+
+	qcom_dwc3_phy_write_readback(phy_dwc3, SSUSB_PHY_PARAM_CTRL_1,
+				     PHY_PARAM_CTRL1_MASK, data);
+
+err_phy_trans:
+	return ret;
+}
+
+static int qcom_dwc3_ss_phy_exit(struct phy *phy)
+{
+	struct qcom_dwc3_usb_phy *phy_dwc3 = phy_get_drvdata(phy);
+
+	/* Sequence to put SSPHY in low power state:
+	 * 1. Clear REF_PHY_EN in PHY_CTRL_REG
+	 * 2. Clear REF_USE_PAD in PHY_CTRL_REG
+	 * 3. Set TEST_POWERED_DOWN in PHY_CTRL_REG to enable PHY retention
+	 */
+	qcom_dwc3_phy_write_readback(phy_dwc3, SSUSB_PHY_CTRL_REG,
+		SSUSB_CTRL_SS_PHY_EN, 0x0);
+	qcom_dwc3_phy_write_readback(phy_dwc3, SSUSB_PHY_CTRL_REG,
+		SSUSB_CTRL_REF_USE_PAD, 0x0);
+	qcom_dwc3_phy_write_readback(phy_dwc3, SSUSB_PHY_CTRL_REG,
+		SSUSB_CTRL_TEST_POWERDOWN, 0x0);
+
+	clk_disable_unprepare(phy_dwc3->ref_clk);
+	clk_disable_unprepare(phy_dwc3->xo_clk);
+
+	return 0;
+}
+
+static const struct qcom_dwc3_phy_drvdata qcom_dwc3_hs_drvdata = {
+	.ops = {
+		.init		= qcom_dwc3_hs_phy_init,
+		.exit		= qcom_dwc3_hs_phy_exit,
+		.owner		= THIS_MODULE,
+	},
+	.clk_rate = 60000000,
+};
+
+static const struct qcom_dwc3_phy_drvdata qcom_dwc3_ss_drvdata = {
+	.ops = {
+		.init		= qcom_dwc3_ss_phy_init,
+		.exit		= qcom_dwc3_ss_phy_exit,
+		.owner		= THIS_MODULE,
+	},
+	.clk_rate = 125000000,
+};
+
+static const struct of_device_id qcom_dwc3_phy_table[] = {
+	{ .compatible = "qcom,dwc3-hs-usb-phy", .data = &qcom_dwc3_hs_drvdata },
+	{ .compatible = "qcom,dwc3-ss-usb-phy", .data = &qcom_dwc3_ss_drvdata },
+	{ /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, qcom_dwc3_phy_table);
+
+static int qcom_dwc3_phy_probe(struct platform_device *pdev)
+{
+	struct qcom_dwc3_usb_phy	*phy_dwc3;
+	struct phy_provider		*phy_provider;
+	struct phy			*generic_phy;
+	struct resource			*res;
+	const struct of_device_id *match;
+	const struct qcom_dwc3_phy_drvdata *data;
+	struct device_node *np;
+
+	phy_dwc3 = devm_kzalloc(&pdev->dev, sizeof(*phy_dwc3), GFP_KERNEL);
+	if (!phy_dwc3)
+		return -ENOMEM;
+
+	match = of_match_node(qcom_dwc3_phy_table, pdev->dev.of_node);
+	data = match->data;
+
+	phy_dwc3->dev = &pdev->dev;
+
+	phy_dwc3->base = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
+							 "regmap");
+	if (IS_ERR_OR_NULL(phy_dwc3->base))
+		return PTR_ERR_OR_ZERO(phy_dwc3->base) ? : -EINVAL;
+
+	phy_dwc3->ref_clk = devm_clk_get(phy_dwc3->dev, "ref");
+	if (IS_ERR(phy_dwc3->ref_clk)) {
+		dev_dbg(phy_dwc3->dev, "cannot get reference clock\n");
+		return PTR_ERR(phy_dwc3->ref_clk);
+	}
+
+	clk_set_rate(phy_dwc3->ref_clk, data->clk_rate);
+
+	phy_dwc3->xo_clk = devm_clk_get(phy_dwc3->dev, "xo");
+	if (IS_ERR(phy_dwc3->xo_clk)) {
+		dev_dbg(phy_dwc3->dev, "cannot get TCXO clock\n");
+		phy_dwc3->xo_clk = NULL;
+	}
+
+	/* Parse device node to probe HSIO settings */
+	np = of_node_get(pdev->dev.of_node);
+	if (!of_compat_cmp(match->compatible, "qcom,dwc3-ss-usb-phy",
+			   strlen(match->compatible))) {
+
+		if (of_property_read_u32(np, "rx_eq", &phy_dwc3->rx_eq) ||
+		    of_property_read_u32(np, "tx_deamp_3_5db",
+					 &phy_dwc3->tx_deamp_3_5db) ||
+		    of_property_read_u32(np, "mpll", &phy_dwc3->mpll)) {
+
+			dev_err(phy_dwc3->dev, "cannot get HSIO settings from device node, using default values\n");
+
+			/* Default HSIO settings */
+			phy_dwc3->rx_eq = SSPHY_RX_EQ_VALUE;
+			phy_dwc3->tx_deamp_3_5db = SSPHY_TX_DEEMPH_3_5DB;
+			phy_dwc3->mpll = SSPHY_MPLL_VALUE;
+		}
+	}
+
+	generic_phy = devm_phy_create(phy_dwc3->dev, pdev->dev.of_node,
+				      &data->ops);
+
+	if (IS_ERR(generic_phy))
+		return PTR_ERR(generic_phy);
+
+	phy_set_drvdata(generic_phy, phy_dwc3);
+	platform_set_drvdata(pdev, phy_dwc3);
+
+	phy_provider = devm_of_phy_provider_register(phy_dwc3->dev,
+			of_phy_simple_xlate);
+
+	if (IS_ERR(phy_provider))
+		return PTR_ERR(phy_provider);
+
+	return 0;
+}
+
+static struct platform_driver qcom_dwc3_phy_driver = {
+	.probe		= qcom_dwc3_phy_probe,
+	.driver		= {
+		.name	= "qcom-dwc3-usb-phy",
+		.owner	= THIS_MODULE,
+		.of_match_table = qcom_dwc3_phy_table,
+	},
+};
+
+module_platform_driver(qcom_dwc3_phy_driver);
+
+MODULE_ALIAS("platform:phy-qcom-dwc3");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
+MODULE_AUTHOR("Ivan T. Ivanov <iivanov@mm-sol.com>");
+MODULE_DESCRIPTION("DesignWare USB3 QCOM PHY driver");
-- 
2.25.1

