[PATCH v8 3/3] phy: Add Qualcomm DWC3 HS/SS PHY driver
From: Andy Gross
Date: Fri Sep 12 2014 - 13:30:11 EST
This patch adds a new driver for the Qualcomm USB 3.0 PHY that exists on some
Qualcomm platforms. This driver uses the generic PHY framework and will
interact with the DWC3 controller.
Signed-off-by: Andy Gross <agross@xxxxxxxxxxxxxx>
---
drivers/phy/Kconfig | 11 +
drivers/phy/Makefile | 1 +
drivers/phy/phy-qcom-dwc3.c | 500 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 512 insertions(+)
create mode 100644 drivers/phy/phy-qcom-dwc3.c
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 0dd7427..5d56161 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -230,4 +230,15 @@ config PHY_XGENE
help
This option enables support for APM X-Gene SoC multi-purpose PHY.
+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.
+
endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 95c69ed..aa16f30 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -28,3 +28,4 @@ obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA) += phy-qcom-ipq806x-sata.o
obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY) += phy-spear1310-miphy.o
obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY) += phy-spear1340-miphy.o
obj-$(CONFIG_PHY_XGENE) += phy-xgene.o
+obj-$(CONFIG_PHY_QCOM_DWC3) += phy-qcom-dwc3.o
diff --git a/drivers/phy/phy-qcom-dwc3.c b/drivers/phy/phy-qcom-dwc3.c
new file mode 100644
index 0000000..05b8e1d
--- /dev/null
+++ b/drivers/phy/phy-qcom-dwc3.c
@@ -0,0 +1,500 @@
+/* Copyright (c) 2013-2014, 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/usb/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.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 (0x00)
+#define SSUSB_PHY_PARAM_CTRL_1 (0x04)
+#define SSUSB_PHY_PARAM_CTRL_2 (0x08)
+#define CR_PROTOCOL_DATA_IN_REG (0x0c)
+#define CR_PROTOCOL_DATA_OUT_REG (0x10)
+#define CR_PROTOCOL_CAP_ADDR_REG (0x14)
+#define CR_PROTOCOL_CAP_DATA_REG (0x18)
+#define CR_PROTOCOL_READ_REG (0x1c)
+#define CR_PROTOCOL_WRITE_REG (0x20)
+
+/* 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 */
+#define SSPHY_CTRL_RX_OVRD_IN_HI(lane) (0x1006 + 0x100 * lane)
+#define SSPHY_CTRL_TX_OVRD_DRV_LO(lane) (0x1002 + 0x100 * lane)
+
+/* 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)
+
+struct qcom_dwc3_usb_phy;
+
+enum qcom_dwc3_phy_id {
+ QCOM_DWC3_PHY_UTMI = 0,
+ QCOM_DWC3_PHY_PIPE,
+ QCOM_DWC3_PHYS_NUM,
+};
+
+struct qcom_dwc3_usb_phy {
+ void __iomem *base;
+ struct device *dev;
+ struct phy *phy;
+ enum qcom_dwc3_phy_id index;
+
+ struct clk *xo_clk;
+ struct clk *ref_clk;
+};
+
+/**
+ * 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 = readl(phy_dwc3->base + offset);
+
+ tmp &= ~mask; /* retain other bits */
+ write_val = tmp | val;
+
+ writel(write_val, phy_dwc3->base + offset);
+
+ /* Read back to see if val was written */
+ tmp = readl(phy_dwc3->base + offset);
+ 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(void __iomem *addr)
+{
+ u32 retry = 10;
+
+ while (true) {
+ if (!readl(addr))
+ 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(void __iomem *base, u32 addr, u32 val)
+{
+ writel(addr, base + CR_PROTOCOL_DATA_IN_REG);
+ writel(0x1, base + CR_PROTOCOL_CAP_ADDR_REG);
+
+ if (wait_for_latch(base + CR_PROTOCOL_CAP_ADDR_REG))
+ return 1;
+
+ writel(val, base + CR_PROTOCOL_DATA_IN_REG);
+ writel(0x1, base + CR_PROTOCOL_CAP_DATA_REG);
+
+ if (wait_for_latch(base + CR_PROTOCOL_CAP_DATA_REG))
+ return 1;
+
+ writel(0x1, base + CR_PROTOCOL_WRITE_REG);
+
+ if (wait_for_latch(base + CR_PROTOCOL_WRITE_REG))
+ return 1;
+
+ return 0;
+}
+
+/**
+ * Read SSPHY register.
+ *
+ * @base - QCOM DWC3 PHY base virtual address.
+ * @addr - SSPHY address to read.
+ */
+static int qcom_dwc3_ss_read_phycreg(void __iomem *base, u32 addr, u32 *val)
+{
+ bool first_read = true;
+
+ writel(addr, base + CR_PROTOCOL_DATA_IN_REG);
+ writel(0x1, base + CR_PROTOCOL_CAP_ADDR_REG);
+
+ if (wait_for_latch(base + CR_PROTOCOL_CAP_ADDR_REG))
+ return 1;
+
+ /*
+ * 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.
+ */
+retry:
+ writel(0x1, base + CR_PROTOCOL_READ_REG);
+
+ if (wait_for_latch(base + CR_PROTOCOL_READ_REG))
+ return 1;
+
+ if (first_read) {
+ readl(base + CR_PROTOCOL_DATA_OUT_REG);
+ first_read = false;
+ goto retry;
+ }
+
+ *val = readl(base + CR_PROTOCOL_DATA_OUT_REG);
+
+ return 0;
+}
+
+static int qcom_dwc3_phy_power_on(struct phy *phy)
+{
+ int ret;
+ struct qcom_dwc3_usb_phy *phy_dwc3 = phy_get_drvdata(phy);
+
+ 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;
+}
+
+static int qcom_dwc3_phy_power_off(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_hs_phy_init(struct qcom_dwc3_usb_phy *phy_dwc3)
+{
+ u32 val;
+
+ /*
+ * 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;
+
+ writel(val, phy_dwc3->base + HSUSB_PHY_CTRL_REG);
+ usleep_range(2000, 2200);
+
+ /* Disable (bypass) VBUS and ID filters */
+ writel(HSUSB_GCFG_XHCI_REV, phy_dwc3->base + QSCRATCH_GENERAL_CFG);
+
+ return 0;
+}
+
+static int qcom_dwc3_ss_phy_init(struct qcom_dwc3_usb_phy *phy_dwc3)
+{
+ u32 data = 0;
+
+ /* reset phy */
+ data = readl_relaxed(phy_dwc3->base + SSUSB_PHY_CTRL_REG);
+ writel_relaxed(data | SSUSB_CTRL_SS_PHY_RESET,
+ phy_dwc3->base + SSUSB_PHY_CTRL_REG);
+ usleep_range(2000, 2200);
+ writel_relaxed(data, phy_dwc3->base + SSUSB_PHY_CTRL_REG);
+
+ /* 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;
+
+ writel_relaxed(data, phy_dwc3->base + SSUSB_PHY_CTRL_REG);
+ msleep(30);
+
+ data |= SSUSB_CTRL_SS_PHY_EN | SSUSB_CTRL_LANE0_PWR_PRESENT;
+ writel_relaxed(data, phy_dwc3->base + SSUSB_PHY_CTRL_REG);
+
+ /*
+ * 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 to 3
+ * LANE0.RX_OVRD_IN_HI.RX_EQ_OVRD set to 1
+ */
+ if (qcom_dwc3_ss_read_phycreg(phy_dwc3->base,
+ SSPHY_CTRL_RX_OVRD_IN_HI(0), &data))
+ return 1;
+
+ 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 |= 0x3 << RX_OVRD_IN_HI_RX_EQ_SHIFT;
+ data |= RX_OVRD_IN_HI_RX_EQ_OVRD;
+ if (qcom_dwc3_ss_write_phycreg(phy_dwc3->base,
+ SSPHY_CTRL_RX_OVRD_IN_HI(0), data))
+ return 1;
+
+ /*
+ * Set EQ and TX launch amplitudes as follows
+ * LANE0.TX_OVRD_DRV_LO.PREEMPH set to 22
+ * LANE0.TX_OVRD_DRV_LO.AMPLITUDE set to 127
+ * LANE0.TX_OVRD_DRV_LO.EN set to 1.
+ */
+ if (qcom_dwc3_ss_read_phycreg(phy_dwc3->base,
+ SSPHY_CTRL_TX_OVRD_DRV_LO(0), &data))
+ return 1;
+
+ data &= ~TX_OVRD_DRV_LO_PREEMPH_MASK;
+ data |= 0x16 << TX_OVRD_DRV_LO_PREEMPH_SHIFT;
+ data &= ~TX_OVRD_DRV_LO_AMPLITUDE_MASK;
+ data |= 0x7f;
+ data |= TX_OVRD_DRV_LO_EN;
+ if (qcom_dwc3_ss_write_phycreg(phy_dwc3->base,
+ SSPHY_CTRL_TX_OVRD_DRV_LO(0), data))
+ return 1;
+
+ /*
+ * Set the QSCRATCH PHY_PARAM_CTRL1 parameters as follows
+ * TX_FULL_SWING [26:20] amplitude to 127
+ * TX_DEEMPH_3_5DB [13:8] to 22
+ * LOS_BIAS [2:0] to 0x5
+ */
+ qcom_dwc3_phy_write_readback(phy_dwc3, SSUSB_PHY_PARAM_CTRL_1,
+ 0x07f03f07, 0x07f01605);
+ return 0;
+}
+
+static int qcom_dwc3_ss_phy_exit(struct qcom_dwc3_usb_phy *phy_dwc3)
+{
+ /* 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
+ * 4. Disable SSPHY ref clk
+ */
+ 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,
+ 0x0, SSUSB_CTRL_TEST_POWERDOWN);
+
+ return 0;
+}
+
+static int qcom_dwc3_phy_init(struct phy *phy)
+{
+ struct qcom_dwc3_usb_phy *phy_dwc3 = phy_get_drvdata(phy);
+
+ switch (phy_dwc3->index) {
+ case QCOM_DWC3_PHY_UTMI:
+ return qcom_dwc3_hs_phy_init(phy_dwc3);
+ case QCOM_DWC3_PHY_PIPE:
+ return qcom_dwc3_ss_phy_init(phy_dwc3);
+ default:
+ dev_err(phy_dwc3->dev, "unknown phy id %d\n",
+ phy_dwc3->index);
+ break;
+ }
+
+ return -EINVAL;
+}
+
+static int qcom_dwc3_phy_exit(struct phy *phy)
+{
+ struct qcom_dwc3_usb_phy *phy_dwc3 = phy_get_drvdata(phy);
+
+ switch (phy_dwc3->index) {
+ case QCOM_DWC3_PHY_UTMI:
+ return 0;
+ case QCOM_DWC3_PHY_PIPE:
+ return qcom_dwc3_ss_phy_exit(phy_dwc3);
+ default:
+ dev_err(phy_dwc3->dev, "unknown phy id %d\n",
+ phy_dwc3->index);
+ break;
+ }
+
+ return -EINVAL;
+}
+
+static struct phy_ops qcom_dwc3_phy_ops = {
+ .init = qcom_dwc3_phy_init,
+ .exit = qcom_dwc3_phy_exit,
+ .power_on = qcom_dwc3_phy_power_on,
+ .power_off = qcom_dwc3_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static const struct of_device_id qcom_dwc3_phy_table[] = {
+ {
+ .compatible = "qcom,dwc3-hs-usb-phy",
+ .data = (void *)QCOM_DWC3_PHY_UTMI,
+ },
+ {
+ .compatible = "qcom,dwc3-ss-usb-phy",
+ .data = (void *)QCOM_DWC3_PHY_PIPE,
+ },
+ { /* 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 resource *res;
+ const struct of_device_id *match;
+
+
+ phy_dwc3 = devm_kzalloc(&pdev->dev, sizeof(*phy_dwc3), GFP_KERNEL);
+ if (!phy_dwc3)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, phy_dwc3);
+
+ phy_dwc3->dev = &pdev->dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ phy_dwc3->base = devm_ioremap_resource(phy_dwc3->dev, res);
+ if (IS_ERR(phy_dwc3->base))
+ return PTR_ERR(phy_dwc3->base);
+
+ 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);
+ }
+
+ match = of_match_node(qcom_dwc3_phy_table, pdev->dev.of_node);
+ phy_dwc3->index = (enum qcom_dwc3_phy_id)match->data;
+
+ switch (phy_dwc3->index) {
+ case QCOM_DWC3_PHY_UTMI:
+ clk_set_rate(phy_dwc3->ref_clk, 60000000);
+ break;
+ case QCOM_DWC3_PHY_PIPE:
+ clk_set_rate(phy_dwc3->ref_clk, 125000000);
+ break;
+ default:
+ dev_err(phy_dwc3->dev, "Invalid phy ID\n");
+ return -EINVAL;
+ }
+
+ 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;
+ }
+
+ phy_dwc3->phy = devm_phy_create(phy_dwc3->dev, NULL, &qcom_dwc3_phy_ops,
+ NULL);
+
+ if (IS_ERR(phy_dwc3->phy))
+ return PTR_ERR(phy_dwc3->phy);
+
+ phy_set_drvdata(phy_dwc3->phy, 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@xxxxxxxxxxxxxx>");
+MODULE_AUTHOR("Ivan T. Ivanov <iivanov@xxxxxxxxxx>");
+MODULE_DESCRIPTION("DesignWare USB3 QCOM PHY driver");
--
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