[PATCH v6 2/6] phy: qcom: Add QCOM SNPS eUSB2 driver

From: Abel Vesa
Date: Wed Feb 08 2023 - 13:34:53 EST


The SM8550 SoC uses Synopsis eUSB2 PHY for USB 2.0.
Add a new driver for it.

The driver is based on a downstream implementation.

Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
---

The v5 version of this patch was here:
https://lore.kernel.org/all/20230207114024.944314-3-abel.vesa@xxxxxxxxxx/

Changes since v5:
* fixed checkpatch indentation warning for ref_clk_freq argument on
"unsupported ref_clk_freq" error

Changes since v4:
* none

Changes since v3:
* none

Changes since v2:
* this time actually dropped the qcom_snps_, which I missed in the v2
* this time actually added the new lines after break in switch clause,
as Vinod suggested, which I missed in the v2

Changes since v1:
* replaced qualcomm with qcom in subject line
* dropped all unnecessary includes
* dropped qcom_snps prefix from qcom_snps_eusb2_hsphy_vreg_names
* properly aligned the arguments for qcom_snps_eusb2_hsphy_write_mask
* added empty lines after break in switch clause, like Vinod suggested

drivers/phy/qualcomm/Kconfig | 9 +
drivers/phy/qualcomm/Makefile | 1 +
drivers/phy/qualcomm/phy-qcom-snps-eusb2.c | 422 +++++++++++++++++++++
3 files changed, 432 insertions(+)
create mode 100644 drivers/phy/qualcomm/phy-qcom-snps-eusb2.c

diff --git a/drivers/phy/qualcomm/Kconfig b/drivers/phy/qualcomm/Kconfig
index 62cf51aab1b8..513322cdf83c 100644
--- a/drivers/phy/qualcomm/Kconfig
+++ b/drivers/phy/qualcomm/Kconfig
@@ -112,6 +112,15 @@ config PHY_QCOM_QUSB2
PHY which is usually paired with either the ChipIdea or Synopsys DWC3
USB IPs on MSM SOCs.

+config PHY_QCOM_SNPS_EUSB2
+ tristate "Qualcomm SNPS eUSB2 PHY Driver"
+ depends on OF && (ARCH_QCOM || COMPILE_TEST)
+ select GENERIC_PHY
+ help
+ Enable support for the USB high-speed SNPS eUSB2 phy on Qualcomm
+ chipsets. The PHY is paired with a Synopsys DWC3 USB controller
+ on Qualcomm SOCs.
+
config PHY_QCOM_USB_HS
tristate "Qualcomm USB HS PHY module"
depends on USB_ULPI_BUS
diff --git a/drivers/phy/qualcomm/Makefile b/drivers/phy/qualcomm/Makefile
index 79dd4e507961..b2c01665622b 100644
--- a/drivers/phy/qualcomm/Makefile
+++ b/drivers/phy/qualcomm/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_PHY_QCOM_QMP_UFS) += phy-qcom-qmp-ufs.o
obj-$(CONFIG_PHY_QCOM_QMP_USB) += phy-qcom-qmp-usb.o

obj-$(CONFIG_PHY_QCOM_QUSB2) += phy-qcom-qusb2.o
+obj-$(CONFIG_PHY_QCOM_SNPS_EUSB2) += phy-qcom-snps-eusb2.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_USB_HS_28NM) += phy-qcom-usb-hs-28nm.o
diff --git a/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c b/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
new file mode 100644
index 000000000000..40a421cf3dd9
--- /dev/null
+++ b/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
@@ -0,0 +1,422 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2023, Linaro Limited
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/reset.h>
+
+#define USB_PHY_UTMI_CTRL0 (0x3c)
+#define SLEEPM BIT(0)
+#define OPMODE_MASK GENMASK(4, 3)
+#define OPMODE_NONDRIVING BIT(3)
+
+#define USB_PHY_UTMI_CTRL5 (0x50)
+#define POR BIT(1)
+
+#define USB_PHY_HS_PHY_CTRL_COMMON0 (0x54)
+#define PHY_ENABLE BIT(0)
+#define SIDDQ_SEL BIT(1)
+#define SIDDQ BIT(2)
+#define RETENABLEN BIT(3)
+#define FSEL_MASK GENMASK(6, 4)
+#define FSEL_19_2_MHZ_VAL (0x0)
+#define FSEL_38_4_MHZ_VAL (0x4)
+
+#define USB_PHY_CFG_CTRL_1 (0x58)
+#define PHY_CFG_PLL_CPBIAS_CNTRL_MASK GENMASK(7, 1)
+
+#define USB_PHY_CFG_CTRL_2 (0x5c)
+#define PHY_CFG_PLL_FB_DIV_7_0_MASK GENMASK(7, 0)
+#define DIV_7_0_19_2_MHZ_VAL (0x90)
+#define DIV_7_0_38_4_MHZ_VAL (0xc8)
+
+#define USB_PHY_CFG_CTRL_3 (0x60)
+#define PHY_CFG_PLL_FB_DIV_11_8_MASK GENMASK(3, 0)
+#define DIV_11_8_19_2_MHZ_VAL (0x1)
+#define DIV_11_8_38_4_MHZ_VAL (0x0)
+
+#define PHY_CFG_PLL_REF_DIV GENMASK(7, 4)
+#define PLL_REF_DIV_VAL (0x0)
+
+#define USB_PHY_HS_PHY_CTRL2 (0x64)
+#define VBUSVLDEXT0 BIT(0)
+#define USB2_SUSPEND_N BIT(2)
+#define USB2_SUSPEND_N_SEL BIT(3)
+#define VBUS_DET_EXT_SEL BIT(4)
+
+#define USB_PHY_CFG_CTRL_4 (0x68)
+#define PHY_CFG_PLL_GMP_CNTRL_MASK GENMASK(1, 0)
+#define PHY_CFG_PLL_INT_CNTRL_MASK GENMASK(7, 2)
+
+#define USB_PHY_CFG_CTRL_5 (0x6c)
+#define PHY_CFG_PLL_PROP_CNTRL_MASK GENMASK(4, 0)
+#define PHY_CFG_PLL_VREF_TUNE_MASK GENMASK(7, 6)
+
+#define USB_PHY_CFG_CTRL_6 (0x70)
+#define PHY_CFG_PLL_VCO_CNTRL_MASK GENMASK(2, 0)
+
+#define USB_PHY_CFG_CTRL_7 (0x74)
+
+#define USB_PHY_CFG_CTRL_8 (0x78)
+#define PHY_CFG_TX_FSLS_VREF_TUNE_MASK GENMASK(1, 0)
+#define PHY_CFG_TX_FSLS_VREG_BYPASS BIT(2)
+#define PHY_CFG_TX_HS_VREF_TUNE_MASK GENMASK(5, 3)
+#define PHY_CFG_TX_HS_XV_TUNE_MASK GENMASK(7, 6)
+
+#define USB_PHY_CFG_CTRL_9 (0x7c)
+#define PHY_CFG_TX_PREEMP_TUNE_MASK GENMASK(2, 0)
+#define PHY_CFG_TX_RES_TUNE_MASK GENMASK(4, 3)
+#define PHY_CFG_TX_RISE_TUNE_MASK GENMASK(6, 5)
+#define PHY_CFG_RCAL_BYPASS BIT(7)
+
+#define USB_PHY_CFG_CTRL_10 (0x80)
+
+#define USB_PHY_CFG0 (0x94)
+#define DATAPATH_CTRL_OVERRIDE_EN BIT(0)
+#define CMN_CTRL_OVERRIDE_EN BIT(1)
+
+#define UTMI_PHY_CMN_CTRL0 (0x98)
+#define TESTBURNIN BIT(6)
+
+#define USB_PHY_FSEL_SEL (0xb8)
+#define FSEL_SEL BIT(0)
+
+#define USB_PHY_APB_ACCESS_CMD (0x130)
+#define RW_ACCESS BIT(0)
+#define APB_START_CMD BIT(1)
+#define APB_LOGIC_RESET BIT(2)
+
+#define USB_PHY_APB_ACCESS_STATUS (0x134)
+#define ACCESS_DONE BIT(0)
+#define TIMED_OUT BIT(1)
+#define ACCESS_ERROR BIT(2)
+#define ACCESS_IN_PROGRESS BIT(3)
+
+#define USB_PHY_APB_ADDRESS (0x138)
+#define APB_REG_ADDR_MASK GENMASK(7, 0)
+
+#define USB_PHY_APB_WRDATA_LSB (0x13c)
+#define APB_REG_WRDATA_7_0_MASK GENMASK(3, 0)
+
+#define USB_PHY_APB_WRDATA_MSB (0x140)
+#define APB_REG_WRDATA_15_8_MASK GENMASK(7, 4)
+
+#define USB_PHY_APB_RDDATA_LSB (0x144)
+#define APB_REG_RDDATA_7_0_MASK GENMASK(3, 0)
+
+#define USB_PHY_APB_RDDATA_MSB (0x148)
+#define APB_REG_RDDATA_15_8_MASK GENMASK(7, 4)
+
+static const char * const eusb2_hsphy_vreg_names[] = {
+ "vdd", "vdda12",
+};
+
+#define EUSB2_NUM_VREGS ARRAY_SIZE(eusb2_hsphy_vreg_names)
+
+struct qcom_snps_eusb2_hsphy {
+ struct phy *phy;
+ void __iomem *base;
+
+ struct clk *ref_clk;
+ struct reset_control *phy_reset;
+
+ struct regulator_bulk_data vregs[EUSB2_NUM_VREGS];
+
+ enum phy_mode mode;
+};
+
+static int qcom_snps_eusb2_hsphy_set_mode(struct phy *p, enum phy_mode mode, int submode)
+{
+ struct qcom_snps_eusb2_hsphy *phy = phy_get_drvdata(p);
+
+ phy->mode = mode;
+
+ return 0;
+}
+
+static void qcom_snps_eusb2_hsphy_write_mask(void __iomem *base, u32 offset,
+ u32 mask, u32 val)
+{
+ u32 reg;
+
+ reg = readl_relaxed(base + offset);
+ reg &= ~mask;
+ reg |= val & mask;
+ writel_relaxed(reg, base + offset);
+
+ /* Ensure above write is completed */
+ readl_relaxed(base + offset);
+}
+
+static void qcom_eusb2_default_parameters(struct qcom_snps_eusb2_hsphy *phy)
+{
+ /* default parameters: tx pre-emphasis */
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_9,
+ PHY_CFG_TX_PREEMP_TUNE_MASK,
+ FIELD_PREP(PHY_CFG_TX_PREEMP_TUNE_MASK, 0));
+
+ /* tx rise/fall time */
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_9,
+ PHY_CFG_TX_RISE_TUNE_MASK,
+ FIELD_PREP(PHY_CFG_TX_RISE_TUNE_MASK, 0x2));
+
+ /* source impedance adjustment */
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_9,
+ PHY_CFG_TX_RES_TUNE_MASK,
+ FIELD_PREP(PHY_CFG_TX_RES_TUNE_MASK, 0x1));
+
+ /* dc voltage level adjustement */
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_8,
+ PHY_CFG_TX_HS_VREF_TUNE_MASK,
+ FIELD_PREP(PHY_CFG_TX_HS_VREF_TUNE_MASK, 0x3));
+
+ /* transmitter HS crossover adjustement */
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_8,
+ PHY_CFG_TX_HS_XV_TUNE_MASK,
+ FIELD_PREP(PHY_CFG_TX_HS_XV_TUNE_MASK, 0x0));
+}
+
+static int qcom_eusb2_ref_clk_init(struct qcom_snps_eusb2_hsphy *phy)
+{
+ unsigned long ref_clk_freq = clk_get_rate(phy->ref_clk);
+
+ switch (ref_clk_freq) {
+ case 19200000:
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL_COMMON0,
+ FSEL_MASK,
+ FIELD_PREP(FSEL_MASK, FSEL_19_2_MHZ_VAL));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_2,
+ PHY_CFG_PLL_FB_DIV_7_0_MASK,
+ DIV_7_0_19_2_MHZ_VAL);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_3,
+ PHY_CFG_PLL_FB_DIV_11_8_MASK,
+ DIV_11_8_19_2_MHZ_VAL);
+ break;
+
+ case 38400000:
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL_COMMON0,
+ FSEL_MASK,
+ FIELD_PREP(FSEL_MASK, FSEL_38_4_MHZ_VAL));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_2,
+ PHY_CFG_PLL_FB_DIV_7_0_MASK,
+ DIV_7_0_38_4_MHZ_VAL);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_3,
+ PHY_CFG_PLL_FB_DIV_11_8_MASK,
+ DIV_11_8_38_4_MHZ_VAL);
+ break;
+
+ default:
+ dev_err(&phy->phy->dev, "unsupported ref_clk_freq:%lu\n", ref_clk_freq);
+ return -EINVAL;
+ }
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_3,
+ PHY_CFG_PLL_REF_DIV, PLL_REF_DIV_VAL);
+
+ return 0;
+}
+
+static int qcom_snps_eusb2_hsphy_init(struct phy *p)
+{
+ struct qcom_snps_eusb2_hsphy *phy = phy_get_drvdata(p);
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(phy->vregs), phy->vregs);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(phy->ref_clk);
+ if (ret) {
+ dev_err(&p->dev, "failed to enable ref clock, %d\n", ret);
+ goto disable_vreg;
+ }
+
+ ret = reset_control_assert(phy->phy_reset);
+ if (ret) {
+ dev_err(&p->dev, "failed to assert phy_reset, %d\n", ret);
+ goto disable_ref_clk;
+ }
+
+ usleep_range(100, 150);
+
+ ret = reset_control_deassert(phy->phy_reset);
+ if (ret) {
+ dev_err(&p->dev, "failed to de-assert phy_reset, %d\n", ret);
+ goto disable_ref_clk;
+ }
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG0,
+ CMN_CTRL_OVERRIDE_EN, CMN_CTRL_OVERRIDE_EN);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_UTMI_CTRL5, POR, POR);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL_COMMON0,
+ PHY_ENABLE | RETENABLEN, PHY_ENABLE | RETENABLEN);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_APB_ACCESS_CMD,
+ APB_LOGIC_RESET, APB_LOGIC_RESET);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, UTMI_PHY_CMN_CTRL0, TESTBURNIN, 0);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_FSEL_SEL,
+ FSEL_SEL, FSEL_SEL);
+
+ /* update ref_clk related registers */
+ ret = qcom_eusb2_ref_clk_init(phy);
+ if (ret)
+ goto disable_ref_clk;
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_1,
+ PHY_CFG_PLL_CPBIAS_CNTRL_MASK,
+ FIELD_PREP(PHY_CFG_PLL_CPBIAS_CNTRL_MASK, 0x1));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_4,
+ PHY_CFG_PLL_INT_CNTRL_MASK,
+ FIELD_PREP(PHY_CFG_PLL_INT_CNTRL_MASK, 0x8));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_4,
+ PHY_CFG_PLL_GMP_CNTRL_MASK,
+ FIELD_PREP(PHY_CFG_PLL_GMP_CNTRL_MASK, 0x1));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_5,
+ PHY_CFG_PLL_PROP_CNTRL_MASK,
+ FIELD_PREP(PHY_CFG_PLL_PROP_CNTRL_MASK, 0x10));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_6,
+ PHY_CFG_PLL_VCO_CNTRL_MASK,
+ FIELD_PREP(PHY_CFG_PLL_VCO_CNTRL_MASK, 0x0));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_CFG_CTRL_5,
+ PHY_CFG_PLL_VREF_TUNE_MASK,
+ FIELD_PREP(PHY_CFG_PLL_VREF_TUNE_MASK, 0x1));
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL2,
+ VBUS_DET_EXT_SEL, VBUS_DET_EXT_SEL);
+
+ /* set default parameters */
+ qcom_eusb2_default_parameters(phy);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL2,
+ USB2_SUSPEND_N_SEL | USB2_SUSPEND_N,
+ USB2_SUSPEND_N_SEL | USB2_SUSPEND_N);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_UTMI_CTRL0, SLEEPM, SLEEPM);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL_COMMON0,
+ SIDDQ_SEL, SIDDQ_SEL);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL_COMMON0,
+ SIDDQ, 0);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_UTMI_CTRL5, POR, 0);
+
+ qcom_snps_eusb2_hsphy_write_mask(phy->base, USB_PHY_HS_PHY_CTRL2,
+ USB2_SUSPEND_N_SEL, 0);
+
+ return 0;
+
+disable_ref_clk:
+ clk_disable_unprepare(phy->ref_clk);
+
+disable_vreg:
+ regulator_bulk_disable(ARRAY_SIZE(phy->vregs), phy->vregs);
+
+ return ret;
+}
+
+static int qcom_snps_eusb2_hsphy_exit(struct phy *p)
+{
+ struct qcom_snps_eusb2_hsphy *phy = phy_get_drvdata(p);
+
+ clk_disable_unprepare(phy->ref_clk);
+
+ regulator_bulk_disable(ARRAY_SIZE(phy->vregs), phy->vregs);
+
+ return 0;
+}
+
+static const struct phy_ops qcom_snps_eusb2_hsphy_ops = {
+ .init = qcom_snps_eusb2_hsphy_init,
+ .exit = qcom_snps_eusb2_hsphy_exit,
+ .set_mode = qcom_snps_eusb2_hsphy_set_mode,
+ .owner = THIS_MODULE,
+};
+
+static int qcom_snps_eusb2_hsphy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct qcom_snps_eusb2_hsphy *phy;
+ struct phy_provider *phy_provider;
+ struct phy *generic_phy;
+ int ret, i;
+ int num;
+
+ phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+ if (!phy)
+ return -ENOMEM;
+
+ phy->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(phy->base))
+ return PTR_ERR(phy->base);
+
+ phy->phy_reset = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(phy->phy_reset))
+ return PTR_ERR(phy->phy_reset);
+
+ phy->ref_clk = devm_clk_get(dev, "ref");
+ if (IS_ERR(phy->ref_clk))
+ return dev_err_probe(dev, PTR_ERR(phy->ref_clk),
+ "failed to get ref clk\n");
+
+ num = ARRAY_SIZE(phy->vregs);
+ for (i = 0; i < num; i++)
+ phy->vregs[i].supply = eusb2_hsphy_vreg_names[i];
+
+ ret = devm_regulator_bulk_get(dev, num, phy->vregs);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "failed to get regulator supplies\n");
+ generic_phy = devm_phy_create(dev, NULL, &qcom_snps_eusb2_hsphy_ops);
+ if (IS_ERR(generic_phy)) {
+ dev_err(dev, "failed to create phy %d\n", ret);
+ return PTR_ERR(generic_phy);
+ }
+
+ dev_set_drvdata(dev, phy);
+ phy_set_drvdata(generic_phy, phy);
+
+ phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+ if (IS_ERR(phy_provider))
+ return PTR_ERR(phy_provider);
+
+ dev_info(dev, "Registered Qcom-eUSB2 phy\n");
+
+ return 0;
+}
+
+static const struct of_device_id qcom_snps_eusb2_hsphy_of_match_table[] = {
+ { .compatible = "qcom,sm8550-snps-eusb2-phy", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, qcom_snps_eusb2_hsphy_of_match_table);
+
+static struct platform_driver qcom_snps_eusb2_hsphy_driver = {
+ .probe = qcom_snps_eusb2_hsphy_probe,
+ .driver = {
+ .name = "qcom-snps-eusb2-hsphy",
+ .of_match_table = qcom_snps_eusb2_hsphy_of_match_table,
+ },
+};
+
+module_platform_driver(qcom_snps_eusb2_hsphy_driver);
+MODULE_DESCRIPTION("Qualcomm SNPS eUSB2 HS PHY driver");
+MODULE_LICENSE("GPL");
--
2.34.1