phy: Add support for Qualcomm's USB HS phy

The high-speed phy on qcom SoCs is controlled via the ULPI
viewport.

Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: <devicetree@vger.kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

1 files changed, 296 insertions, 0 deletions

diff --git a/drivers/phy/phy-qcom-usb-hs.c b/drivers/phy/phy-qcom-usb-hs.c
new file mode 100644
index 000000000000..94dfbfd739c3
--- /dev/null
+++ b/drivers/phy/phy-qcom-usb-hs.c
@@ -0,0 +1,296 @@
+/**
+ * Copyright (C) 2016 Linaro Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/ulpi/driver.h>
+#include <linux/ulpi/regs.h>
+#include <linux/clk.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of_device.h>
+#include <linux/reset.h>
+#include <linux/extcon.h>
+#include <linux/notifier.h>
+
+#include "ulpi_phy.h"
+
+#define ULPI_PWR_CLK_MNG_REG		0x88
+# define ULPI_PWR_OTG_COMP_DISABLE	BIT(0)
+
+#define ULPI_MISC_A			0x96
+# define ULPI_MISC_A_VBUSVLDEXTSEL	BIT(1)
+# define ULPI_MISC_A_VBUSVLDEXT		BIT(0)
+
+
+struct ulpi_seq {
+	u8 addr;
+	u8 val;
+};
+
+struct qcom_usb_hs_phy {
+	struct ulpi *ulpi;
+	struct phy *phy;
+	struct clk *ref_clk;
+	struct clk *sleep_clk;
+	struct regulator *v1p8;
+	struct regulator *v3p3;
+	struct reset_control *reset;
+	struct ulpi_seq *init_seq;
+	struct extcon_dev *vbus_edev;
+	struct notifier_block vbus_notify;
+};
+
+static int qcom_usb_hs_phy_set_mode(struct phy *phy, enum phy_mode mode)
+{
+	struct qcom_usb_hs_phy *uphy = phy_get_drvdata(phy);
+	u8 addr;
+	int ret;
+
+	if (!uphy->vbus_edev) {
+		u8 val = 0;
+
+		switch (mode) {
+		case PHY_MODE_USB_OTG:
+		case PHY_MODE_USB_HOST:
+			val |= ULPI_INT_IDGRD;
+		case PHY_MODE_USB_DEVICE:
+			val |= ULPI_INT_SESS_VALID;
+		default:
+			break;
+		}
+
+		ret = ulpi_write(uphy->ulpi, ULPI_USB_INT_EN_RISE, val);
+		if (ret)
+			return ret;
+		ret = ulpi_write(uphy->ulpi, ULPI_USB_INT_EN_FALL, val);
+	} else {
+		switch (mode) {
+		case PHY_MODE_USB_OTG:
+		case PHY_MODE_USB_DEVICE:
+			addr = ULPI_SET(ULPI_MISC_A);
+			break;
+		case PHY_MODE_USB_HOST:
+			addr = ULPI_CLR(ULPI_MISC_A);
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		ret = ulpi_write(uphy->ulpi, ULPI_SET(ULPI_PWR_CLK_MNG_REG),
+				 ULPI_PWR_OTG_COMP_DISABLE);
+		if (ret)
+			return ret;
+		ret = ulpi_write(uphy->ulpi, addr, ULPI_MISC_A_VBUSVLDEXTSEL);
+	}
+
+	return ret;
+}
+
+static int
+qcom_usb_hs_phy_vbus_notifier(struct notifier_block *nb, unsigned long event,
+			      void *ptr)
+{
+	struct qcom_usb_hs_phy *uphy;
+	u8 addr;
+
+	uphy = container_of(nb, struct qcom_usb_hs_phy, vbus_notify);
+
+	if (event)
+		addr = ULPI_SET(ULPI_MISC_A);
+	else
+		addr = ULPI_CLR(ULPI_MISC_A);
+
+	return ulpi_write(uphy->ulpi, addr, ULPI_MISC_A_VBUSVLDEXT);
+}
+
+static int qcom_usb_hs_phy_power_on(struct phy *phy)
+{
+	struct qcom_usb_hs_phy *uphy = phy_get_drvdata(phy);
+	struct ulpi *ulpi = uphy->ulpi;
+	const struct ulpi_seq *seq;
+	int ret, state;
+
+	ret = clk_prepare_enable(uphy->ref_clk);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(uphy->sleep_clk);
+	if (ret)
+		goto err_sleep;
+
+	ret = regulator_set_load(uphy->v1p8, 50000);
+	if (ret < 0)
+		goto err_1p8;
+
+	ret = regulator_enable(uphy->v1p8);
+	if (ret)
+		goto err_1p8;
+
+	ret = regulator_set_voltage_triplet(uphy->v3p3, 3050000, 3300000,
+					    3300000);
+	if (ret)
+		goto err_3p3;
+
+	ret = regulator_set_load(uphy->v3p3, 50000);
+	if (ret < 0)
+		goto err_3p3;
+
+	ret = regulator_enable(uphy->v3p3);
+	if (ret)
+		goto err_3p3;
+
+	for (seq = uphy->init_seq; seq->addr; seq++) {
+		ret = ulpi_write(ulpi, ULPI_EXT_VENDOR_SPECIFIC + seq->addr,
+				 seq->val);
+		if (ret)
+			goto err_ulpi;
+	}
+
+	if (uphy->reset) {
+		ret = reset_control_reset(uphy->reset);
+		if (ret)
+			goto err_ulpi;
+	}
+
+	if (uphy->vbus_edev) {
+		state = extcon_get_cable_state_(uphy->vbus_edev, EXTCON_USB);
+		/* setup initial state */
+		qcom_usb_hs_phy_vbus_notifier(&uphy->vbus_notify, state,
+					      uphy->vbus_edev);
+		ret = extcon_register_notifier(uphy->vbus_edev, EXTCON_USB,
+				&uphy->vbus_notify);
+		if (ret)
+			goto err_ulpi;
+	}
+
+	return 0;
+err_ulpi:
+	regulator_disable(uphy->v3p3);
+err_3p3:
+	regulator_disable(uphy->v1p8);
+err_1p8:
+	clk_disable_unprepare(uphy->sleep_clk);
+err_sleep:
+	clk_disable_unprepare(uphy->ref_clk);
+	return ret;
+}
+
+static int qcom_usb_hs_phy_power_off(struct phy *phy)
+{
+	int ret;
+	struct qcom_usb_hs_phy *uphy = phy_get_drvdata(phy);
+
+	if (uphy->vbus_edev) {
+		ret = extcon_unregister_notifier(uphy->vbus_edev, EXTCON_USB,
+						 &uphy->vbus_notify);
+		if (ret)
+			return ret;
+	}
+
+	regulator_disable(uphy->v3p3);
+	regulator_disable(uphy->v1p8);
+	clk_disable_unprepare(uphy->sleep_clk);
+	clk_disable_unprepare(uphy->ref_clk);
+
+	return 0;
+}
+
+static const struct phy_ops qcom_usb_hs_phy_ops = {
+	.power_on = qcom_usb_hs_phy_power_on,
+	.power_off = qcom_usb_hs_phy_power_off,
+	.set_mode = qcom_usb_hs_phy_set_mode,
+	.owner = THIS_MODULE,
+};
+
+static int qcom_usb_hs_phy_probe(struct ulpi *ulpi)
+{
+	struct qcom_usb_hs_phy *uphy;
+	struct phy_provider *p;
+	struct clk *clk;
+	struct regulator *reg;
+	struct reset_control *reset;
+	int size;
+	int ret;
+
+	uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
+	if (!uphy)
+		return -ENOMEM;
+	ulpi_set_drvdata(ulpi, uphy);
+	uphy->ulpi = ulpi;
+
+	size = of_property_count_u8_elems(ulpi->dev.of_node, "qcom,init-seq");
+	if (size < 0)
+		size = 0;
+	uphy->init_seq = devm_kmalloc_array(&ulpi->dev, (size / 2) + 1,
+					   sizeof(*uphy->init_seq), GFP_KERNEL);
+	if (!uphy->init_seq)
+		return -ENOMEM;
+	ret = of_property_read_u8_array(ulpi->dev.of_node, "qcom,init-seq",
+					(u8 *)uphy->init_seq, size);
+	if (ret && size)
+		return ret;
+	/* NUL terminate */
+	uphy->init_seq[size / 2].addr = uphy->init_seq[size / 2].val = 0;
+
+	uphy->ref_clk = clk = devm_clk_get(&ulpi->dev, "ref");
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	uphy->sleep_clk = clk = devm_clk_get(&ulpi->dev, "sleep");
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	uphy->v1p8 = reg = devm_regulator_get(&ulpi->dev, "v1p8");
+	if (IS_ERR(reg))
+		return PTR_ERR(reg);
+
+	uphy->v3p3 = reg = devm_regulator_get(&ulpi->dev, "v3p3");
+	if (IS_ERR(reg))
+		return PTR_ERR(reg);
+
+	uphy->reset = reset = devm_reset_control_get(&ulpi->dev, "por");
+	if (IS_ERR(reset)) {
+		if (PTR_ERR(reset) == -EPROBE_DEFER)
+			return PTR_ERR(reset);
+		uphy->reset = NULL;
+	}
+
+	uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
+				    &qcom_usb_hs_phy_ops);
+	if (IS_ERR(uphy->phy))
+		return PTR_ERR(uphy->phy);
+
+	uphy->vbus_edev = extcon_get_edev_by_phandle(&ulpi->dev, 0);
+	if (IS_ERR(uphy->vbus_edev)) {
+		if (PTR_ERR(uphy->vbus_edev) != -ENODEV)
+			return PTR_ERR(uphy->vbus_edev);
+		uphy->vbus_edev = NULL;
+	}
+
+	uphy->vbus_notify.notifier_call = qcom_usb_hs_phy_vbus_notifier;
+	phy_set_drvdata(uphy->phy, uphy);
+
+	p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
+	return PTR_ERR_OR_ZERO(p);
+}
+
+static const struct of_device_id qcom_usb_hs_phy_match[] = {
+	{ .compatible = "qcom,usb-hs-phy", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, qcom_usb_hs_phy_match);
+
+static struct ulpi_driver qcom_usb_hs_phy_driver = {
+	.probe = qcom_usb_hs_phy_probe,
+	.driver = {
+		.name = "qcom_usb_hs_phy",
+		.of_match_table = qcom_usb_hs_phy_match,
+	},
+};
+module_ulpi_driver(qcom_usb_hs_phy_driver);
+
+MODULE_DESCRIPTION("Qualcomm USB HS phy");
+MODULE_LICENSE("GPL v2");