[PATCH v6 08/13] usb: typec: tcpci_mt6370: Add MediaTek MT6370 tcpci driver

[ChiaEn Wu <peterwu.pub@gmail.com>]

From: ChiYuan Huang <cy_huang@richtek.com>

The MediaTek MT6370 is a highly-integrated smart power management IC,
which includes a single cell Li-Ion/Li-Polymer switching battery
charger, a USB Type-C & Power Delivery (PD) controller, dual
Flash LED current sources, a RGB LED driver, a backlight WLED driver,
a display bias driver and a general LDO for portable devices.

Add support for the Type-C & Power Delivery controller in
MediaTek MT6370 IC.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---

v6
- Convert tcpci as device resource managed with 'devm_add_action_or_reset' API.
- Refine remvoe callback.
- Refine the commit text from 'This commit add' to 'Add'.
---
 drivers/usb/typec/tcpm/Kconfig        |  11 ++
 drivers/usb/typec/tcpm/Makefile       |   1 +
 drivers/usb/typec/tcpm/tcpci_mt6370.c | 208 ++++++++++++++++++++++++++++++++++
 3 files changed, 220 insertions(+)
 create mode 100644 drivers/usb/typec/tcpm/tcpci_mt6370.c

diff --git a/drivers/usb/typec/tcpm/Kconfig b/drivers/usb/typec/tcpm/Kconfig
index 073fd2e..e6b88ca 100644
--- a/drivers/usb/typec/tcpm/Kconfig
+++ b/drivers/usb/typec/tcpm/Kconfig
@@ -35,6 +35,17 @@ config TYPEC_MT6360
 	  USB Type-C. It works with Type-C Port Controller Manager
 	  to provide USB PD and USB Type-C functionalities.
 
+config TYPEC_TCPCI_MT6370
+	tristate "MediaTek MT6370 Type-C driver"
+	depends on MFD_MT6370
+	help
+	  MediaTek MT6370 is a multi-functional IC that includes
+	  USB Type-C. It works with Type-C Port Controller Manager
+	  to provide USB PD and USB Type-C functionalities.
+
+	  This driver can also be built as a module. The module
+	  will be called "tcpci_mt6370".
+
 config TYPEC_TCPCI_MAXIM
 	tristate "Maxim TCPCI based Type-C chip driver"
 	help
diff --git a/drivers/usb/typec/tcpm/Makefile b/drivers/usb/typec/tcpm/Makefile
index 7d499f3..906d9dc 100644
--- a/drivers/usb/typec/tcpm/Makefile
+++ b/drivers/usb/typec/tcpm/Makefile
@@ -6,4 +6,5 @@ typec_wcove-y				:= wcove.o
 obj-$(CONFIG_TYPEC_TCPCI)		+= tcpci.o
 obj-$(CONFIG_TYPEC_RT1711H)		+= tcpci_rt1711h.o
 obj-$(CONFIG_TYPEC_MT6360)		+= tcpci_mt6360.o
+obj-$(CONFIG_TYPEC_TCPCI_MT6370)	+= tcpci_mt6370.o
 obj-$(CONFIG_TYPEC_TCPCI_MAXIM)		+= tcpci_maxim.o
diff --git a/drivers/usb/typec/tcpm/tcpci_mt6370.c b/drivers/usb/typec/tcpm/tcpci_mt6370.c
new file mode 100644
index 0000000..4f53319
--- /dev/null
+++ b/drivers/usb/typec/tcpm/tcpci_mt6370.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Richtek Technology Corp.
+ *
+ * Author: ChiYuan Huang <cy_huang@richtek.com>
+ */
+
+#include <linux/bits.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeup.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/usb/tcpm.h>
+#include "tcpci.h"
+
+#define MT6370_REG_SYSCTRL8	0x9B
+
+#define MT6370_AUTOIDLE_MASK	BIT(3)
+
+#define MT6370_VENDOR_ID	0x29CF
+#define MT6370_TCPC_DID_A	0x2170
+
+struct mt6370_priv {
+	struct device *dev;
+	struct regulator *vbus;
+	struct tcpci *tcpci;
+	struct tcpci_data tcpci_data;
+};
+
+static const struct reg_sequence mt6370_reg_init[] = {
+	REG_SEQ(0xA0, 0x1, 1000),
+	REG_SEQ(0x81, 0x38, 0),
+	REG_SEQ(0x82, 0x82, 0),
+	REG_SEQ(0xBA, 0xFC, 0),
+	REG_SEQ(0xBB, 0x50, 0),
+	REG_SEQ(0x9E, 0x8F, 0),
+	REG_SEQ(0xA1, 0x5, 0),
+	REG_SEQ(0xA2, 0x4, 0),
+	REG_SEQ(0xA3, 0x4A, 0),
+	REG_SEQ(0xA4, 0x01, 0),
+	REG_SEQ(0x95, 0x01, 0),
+	REG_SEQ(0x80, 0x71, 0),
+	REG_SEQ(0x9B, 0x3A, 1000),
+};
+
+static int mt6370_tcpc_init(struct tcpci *tcpci, struct tcpci_data *data)
+{
+	u16 did;
+	int ret;
+
+	ret = regmap_register_patch(data->regmap, mt6370_reg_init,
+				    ARRAY_SIZE(mt6370_reg_init));
+	if (ret)
+		return ret;
+
+	ret = regmap_raw_read(data->regmap, TCPC_BCD_DEV, &did, sizeof(u16));
+	if (ret)
+		return ret;
+
+	if (did == MT6370_TCPC_DID_A)
+		return regmap_write(data->regmap, TCPC_FAULT_CTRL, 0x80);
+
+	return 0;
+}
+
+static int mt6370_tcpc_set_vconn(struct tcpci *tcpci, struct tcpci_data *data,
+				 bool enable)
+{
+	return regmap_update_bits(data->regmap, MT6370_REG_SYSCTRL8,
+				  MT6370_AUTOIDLE_MASK,
+				  !enable ? MT6370_AUTOIDLE_MASK : 0);
+}
+
+static int mt6370_tcpc_set_vbus(struct tcpci *tcpci, struct tcpci_data *data,
+				bool source, bool sink)
+{
+	struct mt6370_priv *priv = container_of(data, struct mt6370_priv,
+						tcpci_data);
+	int ret;
+
+	ret = regulator_is_enabled(priv->vbus);
+	if (ret < 0)
+		return ret;
+
+	if (ret && !source)
+		return regulator_disable(priv->vbus);
+
+	if (!ret && source)
+		return regulator_enable(priv->vbus);
+
+	return 0;
+}
+
+static irqreturn_t mt6370_irq_handler(int irq, void *dev_id)
+{
+	struct mt6370_priv *priv = dev_id;
+
+	return tcpci_irq(priv->tcpci);
+}
+
+static int mt6370_check_vendor_info(struct mt6370_priv *priv)
+{
+	struct regmap *regmap = priv->tcpci_data.regmap;
+	u16 vid;
+	int ret;
+
+	ret = regmap_raw_read(regmap, TCPC_VENDOR_ID, &vid, sizeof(u16));
+	if (ret)
+		return ret;
+
+	if (vid != MT6370_VENDOR_ID)
+		return dev_err_probe(priv->dev, -ENODEV,
+				     "Vendor ID not correct 0x%02x\n", vid);
+
+	return 0;
+}
+
+static void mt6370_unregister_tcpci_port(void *tcpci)
+{
+	tcpci_unregister_port(tcpci);
+}
+
+static int mt6370_tcpc_probe(struct platform_device *pdev)
+{
+	struct mt6370_priv *priv;
+	struct device *dev = &pdev->dev;
+	int irq, ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = dev;
+
+	priv->tcpci_data.regmap = dev_get_regmap(dev->parent, NULL);
+	if (!priv->tcpci_data.regmap)
+		return dev_err_probe(dev, -ENODEV, "Failed to init regmap\n");
+
+	ret = mt6370_check_vendor_info(priv);
+	if (ret)
+		return ret;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return dev_err_probe(dev, irq, "Failed to get irq\n");
+
+	/* Assign TCPCI feature and ops */
+	priv->tcpci_data.auto_discharge_disconnect = 1;
+	priv->tcpci_data.init = mt6370_tcpc_init;
+	priv->tcpci_data.set_vconn = mt6370_tcpc_set_vconn;
+
+	priv->vbus = devm_regulator_get_optional(dev, "vbus");
+	if (!IS_ERR(priv->vbus))
+		priv->tcpci_data.set_vbus = mt6370_tcpc_set_vbus;
+
+	priv->tcpci = tcpci_register_port(dev, &priv->tcpci_data);
+	if (IS_ERR(priv->tcpci))
+		return dev_err_probe(dev, PTR_ERR(priv->tcpci),
+				     "Failed to register tcpci port\n");
+
+	ret = devm_add_action_or_reset(dev, mt6370_unregister_tcpci_port,
+				       priv->tcpci);
+	if (ret)
+		return ret;
+
+	ret = devm_request_threaded_irq(dev, irq, NULL, mt6370_irq_handler,
+					IRQF_ONESHOT, dev_name(dev), priv);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to allocate irq\n");
+
+	device_init_wakeup(dev, true);
+	dev_pm_set_wake_irq(dev, irq);
+
+	return 0;
+}
+
+static int mt6370_tcpc_remove(struct platform_device *pdev)
+{
+	dev_pm_clear_wake_irq(&pdev->dev);
+	device_init_wakeup(&pdev->dev, false);
+
+	return 0;
+}
+
+static const struct of_device_id mt6370_tcpc_devid_table[] = {
+	{ .compatible = "mediatek,mt6370-tcpc" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, mt6370_tcpc_devid_table);
+
+static struct platform_driver mt6370_tcpc_driver = {
+	.driver = {
+		.name = "mt6370-tcpc",
+		.of_match_table = mt6370_tcpc_devid_table,
+	},
+	.probe = mt6370_tcpc_probe,
+	.remove = mt6370_tcpc_remove,
+};
+module_platform_driver(mt6370_tcpc_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
+MODULE_DESCRIPTION("MT6370 USB Type-C Port Controller Interface Driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4