PM8550B contains a eUSB2 repeater used for making the eUSB2 from
SM8550 USB 2.0 compliant.
Add a platform specific repeater driver. It implements ops for init,
reset and power on/off. On init, there is a configuration table that
needs to be written to the repeater's registers.
Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
---
drivers/usb/repeater/Kconfig | 11 +
drivers/usb/repeater/Makefile | 1 +
.../usb/repeater/repeater-qcom-pmic-eusb2.c | 251 ++++++++++++++++++
3 files changed, 263 insertions(+)
create mode 100644 drivers/usb/repeater/repeater-qcom-pmic-eusb2.c
diff --git a/drivers/usb/repeater/Kconfig b/drivers/usb/repeater/Kconfig
index e12cd22c0adb..20baeb8f950c 100644
--- a/drivers/usb/repeater/Kconfig
+++ b/drivers/usb/repeater/Kconfig
@@ -7,3 +7,14 @@ config USB_REPEATER
driver to bind together and to provide the USB driver ways to perform
set of operations with repeater for USB2 functionality using PHY and
controller driver.
+
+config QCOM_PMIC_EUSB2_REPEATER
+ tristate "USB eUSB2 Repeater driver"
+ select USB_REPEATER
+ help
+ Enable this to support the USB eUSB2 repeater on Qualcomm PMIC chips.
+ This driver provides support to reset, initialize, power up and configure
+ the eUSB2 repeater for USB HS/FS/LS functionality where eUSB2 repeater
+ is used.
+
+ To compile the driver as a module, choose M here.
diff --git a/drivers/usb/repeater/Makefile b/drivers/usb/repeater/Makefile
index 2d1b5f348976..fed128407315 100644
--- a/drivers/usb/repeater/Makefile
+++ b/drivers/usb/repeater/Makefile
@@ -4,3 +4,4 @@
#
obj-$(CONFIG_USB_REPEATER) += repeater.o
+obj-$(CONFIG_QCOM_PMIC_EUSB2_REPEATER) += repeater-qcom-pmic-eusb2.o
diff --git a/drivers/usb/repeater/repeater-qcom-pmic-eusb2.c b/drivers/usb/repeater/repeater-qcom-pmic-eusb2.c
new file mode 100644
index 000000000000..1b6d46c28da4
--- /dev/null
+++ b/drivers/usb/repeater/repeater-qcom-pmic-eusb2.c
@@ -0,0 +1,251 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <linux/usb/repeater.h>
+
+/* eUSB2 status registers */
+#define EUSB2_RPTR_STATUS 0x08
+#define RPTR_OK BIT(7)
+
+/* eUSB2 control registers */
+#define EUSB2_EN_CTL1 0x46
+#define EUSB2_RPTR_EN BIT(7)
+
+#define PHY_HOST_MODE BIT(0)
+#define EUSB2_FORCE_EN_5 0xE8
+#define F_CLK_19P2M_EN BIT(6)
+#define F_CLK_19P2M_EN_SHIFT 6
+
+#define EUSB2_FORCE_VAL_5 0xED
+#define V_CLK_19P2M_EN BIT(6)
+#define V_CLK_19P2M_EN_SHIFT 6
+
+#define EUSB2_TUNE_IUSB2 0x51
+#define EUSB2_TUNE_SQUELCH_U 0x54
+#define EUSB2_TUNE_USB2_PREEM 0x57
+
+#define QCOM_EUSB2_REPEATER_INIT_CFG(o, v) \
+ { \
+ .offset = o, \
+ .val = v, \
+ }
+
+#define to_qcom_eusb2_repeater(x) \
+ container_of((x), struct qcom_eusb2_repeater, repeater)
+
+struct qcom_eusb2_repeater_init_tbl {
+ unsigned int offset;
+ unsigned int val;
+};
+
+struct qcom_eusb2_repeater {
+ struct usb_repeater repeater;
+ struct regmap *regmap;
+ u16 base;
+ struct regulator_bulk_data *vregs;
+ const struct qcom_eusb2_repeater_cfg *cfg;
+};
+
+struct qcom_eusb2_repeater_cfg {
+ const struct qcom_eusb2_repeater_init_tbl *init_tbl;
+ int init_tbl_num;
+ /* regulators to be requested */
+ const char * const *vreg_list;
+ int num_vregs;
+};
+
+static const char * const pm8550b_vreg_l[] = {
+ "vdd18", "vdd3",
+};
+
+static const struct qcom_eusb2_repeater_init_tbl pm8550b_init_tbl[] = {
+ QCOM_EUSB2_REPEATER_INIT_CFG(EUSB2_TUNE_IUSB2, 0x8),
+ QCOM_EUSB2_REPEATER_INIT_CFG(EUSB2_TUNE_SQUELCH_U, 0x3),
+ QCOM_EUSB2_REPEATER_INIT_CFG(EUSB2_TUNE_USB2_PREEM, 0x5),
+};
+
+static const struct qcom_eusb2_repeater_cfg pm8550b_eusb2_cfg = {
+ .init_tbl = pm8550b_init_tbl,
+ .init_tbl_num = ARRAY_SIZE(pm8550b_init_tbl),
+ .vreg_list = pm8550b_vreg_l,
+ .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
+};
+
+static int qcom_eusb2_repeater_init_vregs(struct qcom_eusb2_repeater *rptr)
+{
+ int num = rptr->cfg->num_vregs;
+ struct device *dev = rptr->repeater.dev;
+ int i;
+
+ rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
+ if (!rptr->vregs)
+ return -ENOMEM;
+
+ for (i = 0; i < num; i++)
+ rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
+
+ return devm_regulator_bulk_get(dev, num, rptr->vregs);
+}
+
+static int qcom_eusb2_repeater_cfg_init(struct qcom_eusb2_repeater *rptr)
+{
+ const struct qcom_eusb2_repeater_init_tbl *init_tbl = rptr->cfg->init_tbl;
+ int num = rptr->cfg->init_tbl_num;
+ int i;
+
+ for (i = 0; i < num; i++)
+ regmap_update_bits(rptr->regmap, rptr->base + init_tbl[i].offset,
+ init_tbl[i].val, init_tbl[i].val);
+ return 0;
+}
+
+static int qcom_eusb2_repeater_init(struct usb_repeater *r)
+{
+ struct qcom_eusb2_repeater *rptr = to_qcom_eusb2_repeater(r);
+ int ret = 0;
+ u32 val;
+
+ qcom_eusb2_repeater_cfg_init(rptr);
+
+ if (r->flags & PHY_HOST_MODE) {
+ /*
+ * CM.Lx is prohibited when repeater is already into Lx state as
+ * per eUSB 1.2 Spec. Below implement software workaround until
+ * PHY and controller is fixing seen observation.
+ */
+ regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_EN_5,
+ F_CLK_19P2M_EN, F_CLK_19P2M_EN);
+ regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_VAL_5,
+ V_CLK_19P2M_EN, V_CLK_19P2M_EN);
+ } else {
+ /*
+ * In device mode clear host mode related workaround as there
+ * is no repeater reset available, and enable/disable of
+ * repeater doesn't clear previous value due to shared
+ * regulators (say host <-> device mode switch).
+ */
+ regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_EN_5,
+ F_CLK_19P2M_EN, 0);
+ regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_VAL_5,
+ V_CLK_19P2M_EN, 0);
+ }
+
+ ret = regmap_read_poll_timeout(rptr->regmap, rptr->base + EUSB2_RPTR_STATUS, val,
+ val & RPTR_OK, 10, 5);
+ if (ret)
+ dev_err(r->dev, "initialization timed-out\n");
+
+ return ret;
+}
+
+static int qcom_eusb2_repeater_reset(struct usb_repeater *r, bool assert)
+{
+ struct qcom_eusb2_repeater *rptr = to_qcom_eusb2_repeater(r);
+
+ return regmap_update_bits(rptr->regmap, rptr->base + EUSB2_EN_CTL1,
+ EUSB2_RPTR_EN, assert ? EUSB2_RPTR_EN : 0x0);
+}
+
+static int qcom_eusb2_repeater_power_on(struct usb_repeater *r)
+{
+ struct qcom_eusb2_repeater *rptr = to_qcom_eusb2_repeater(r);
+
+ return regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
+}
+
+static int qcom_eusb2_repeater_power_off(struct usb_repeater *r)
+{
+ struct qcom_eusb2_repeater *rptr = to_qcom_eusb2_repeater(r);
+
+ return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
+}
+
+static int qcom_eusb2_repeater_probe(struct platform_device *pdev)
+{
+ struct qcom_eusb2_repeater *rptr;
+ struct device *dev = &pdev->dev;
+ struct device_node *node;
+ u32 res;
+ int ret;
+
+ node = dev->of_node;
+
+ rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
+ if (!rptr)
+ return -ENOMEM;
+
+ rptr->repeater.dev = dev;
+ dev_set_drvdata(dev, rptr);
+
+ /* Get the specific init parameters of QMP phy */
+ rptr->cfg = of_device_get_match_data(dev);
+ if (!rptr->cfg)
+ return -EINVAL;
+
+ rptr->regmap = dev_get_regmap(dev->parent, NULL);
+ if (!rptr->regmap)
+ return -ENXIO;
+
+ ret = of_property_read_u32(node, "reg", &res);
+ if (ret < 0)
+ return ret;
+
+ rptr->base = res;
+
+ ret = qcom_eusb2_repeater_init_vregs(rptr);
+ if (ret < 0) {
+ dev_err(dev, "unable to get supplies\n");
+ return ret;
+ }
+
+ rptr->repeater.init = qcom_eusb2_repeater_init;
+ rptr->repeater.reset = qcom_eusb2_repeater_reset;
+ rptr->repeater.power_on = qcom_eusb2_repeater_power_on;
+ rptr->repeater.power_off = qcom_eusb2_repeater_power_off;
+
+ return usb_add_repeater_dev(&rptr->repeater);
+}
+
+static int qcom_eusb2_repeater_remove(struct platform_device *pdev)
+{
+ struct qcom_eusb2_repeater *rptr = platform_get_drvdata(pdev);
+
+ if (!rptr)
+ return 0;
+
+ usb_remove_repeater_dev(&rptr->repeater);
+ qcom_eusb2_repeater_power_off(&rptr->repeater);
+ return 0;
+}
+
+static const struct of_device_id qcom_eusb2_repeater_id_table[] = {
+ {
+ .compatible = "qcom,pm8550b-eusb2-repeater",
+ .data = &pm8550b_eusb2_cfg,
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, qcom_eusb2_repeater_id_table);
+
+static struct platform_driver qcom_eusb2_repeater_driver = {
+ .probe = qcom_eusb2_repeater_probe,
+ .remove = qcom_eusb2_repeater_remove,
+ .driver = {
+ .name = "qcom-pmic-eusb2-repeater",
+ .of_match_table = of_match_ptr(qcom_eusb2_repeater_id_table),
+ },
+};
+
+module_platform_driver(qcom_eusb2_repeater_driver);
+MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 repeater driver");
+MODULE_LICENSE("GPL");
--
2.34.1
