diff options
| -rw-r--r-- | drivers/extcon/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/extcon/Makefile | 1 | ||||
| -rw-r--r-- | drivers/extcon/extcon-usbc-tusb320.c | 184 |
3 files changed, 193 insertions, 0 deletions
diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig index aac507bff135..af58ebca2bf6 100644 --- a/drivers/extcon/Kconfig +++ b/drivers/extcon/Kconfig @@ -186,4 +186,12 @@ config EXTCON_USBC_CROS_EC Say Y here to enable USB Type C cable detection extcon support when using Chrome OS EC based USB Type-C ports. +config EXTCON_USBC_TUSB320 + tristate "TI TUSB320 USB-C extcon support" + depends on I2C + select REGMAP_I2C + help + Say Y here to enable support for USB Type C cable detection extcon + support using a TUSB320. + endif diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile index 52096fd8a216..fe10a1b7d18b 100644 --- a/drivers/extcon/Makefile +++ b/drivers/extcon/Makefile @@ -25,3 +25,4 @@ obj-$(CONFIG_EXTCON_RT8973A) += extcon-rt8973a.o obj-$(CONFIG_EXTCON_SM5502) += extcon-sm5502.o obj-$(CONFIG_EXTCON_USB_GPIO) += extcon-usb-gpio.o obj-$(CONFIG_EXTCON_USBC_CROS_EC) += extcon-usbc-cros-ec.o +obj-$(CONFIG_EXTCON_USBC_TUSB320) += extcon-usbc-tusb320.o diff --git a/drivers/extcon/extcon-usbc-tusb320.c b/drivers/extcon/extcon-usbc-tusb320.c new file mode 100644 index 000000000000..805af73b4152 --- /dev/null +++ b/drivers/extcon/extcon-usbc-tusb320.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0 +/** + * drivers/extcon/extcon-tusb320.c - TUSB320 extcon driver + * + * Copyright (C) 2020 National Instruments Corporation + * Author: Michael Auchter <michael.auchter@ni.com> + */ + +#include <linux/extcon-provider.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#define TUSB320_REG9 0x9 +#define TUSB320_REG9_ATTACHED_STATE_SHIFT 6 +#define TUSB320_REG9_ATTACHED_STATE_MASK 0x3 +#define TUSB320_REG9_CABLE_DIRECTION BIT(5) +#define TUSB320_REG9_INTERRUPT_STATUS BIT(4) +#define TUSB320_ATTACHED_STATE_NONE 0x0 +#define TUSB320_ATTACHED_STATE_DFP 0x1 +#define TUSB320_ATTACHED_STATE_UFP 0x2 +#define TUSB320_ATTACHED_STATE_ACC 0x3 + +struct tusb320_priv { + struct device *dev; + struct regmap *regmap; + struct extcon_dev *edev; +}; + +static const char * const tusb_attached_states[] = { + [TUSB320_ATTACHED_STATE_NONE] = "not attached", + [TUSB320_ATTACHED_STATE_DFP] = "downstream facing port", + [TUSB320_ATTACHED_STATE_UFP] = "upstream facing port", + [TUSB320_ATTACHED_STATE_ACC] = "accessory", +}; + +static const unsigned int tusb320_extcon_cable[] = { + EXTCON_USB, + EXTCON_USB_HOST, + EXTCON_NONE, +}; + +static int tusb320_check_signature(struct tusb320_priv *priv) +{ + static const char sig[] = { '\0', 'T', 'U', 'S', 'B', '3', '2', '0' }; + unsigned val; + int i, ret; + + for (i = 0; i < sizeof(sig); i++) { + ret = regmap_read(priv->regmap, sizeof(sig) - 1 - i, &val); + if (ret < 0) + return ret; + if (val != sig[i]) { + dev_err(priv->dev, "signature mismatch!\n"); + return -ENODEV; + } + } + + return 0; +} + +static irqreturn_t tusb320_irq_handler(int irq, void *dev_id) +{ + struct tusb320_priv *priv = dev_id; + int state, polarity; + unsigned reg; + + if (regmap_read(priv->regmap, TUSB320_REG9, ®)) { + dev_err(priv->dev, "error during i2c read!\n"); + return IRQ_NONE; + } + + if (!(reg & TUSB320_REG9_INTERRUPT_STATUS)) + return IRQ_NONE; + + state = (reg >> TUSB320_REG9_ATTACHED_STATE_SHIFT) & + TUSB320_REG9_ATTACHED_STATE_MASK; + polarity = !!(reg & TUSB320_REG9_CABLE_DIRECTION); + + dev_dbg(priv->dev, "attached state: %s, polarity: %d\n", + tusb_attached_states[state], polarity); + + extcon_set_state(priv->edev, EXTCON_USB, + state == TUSB320_ATTACHED_STATE_UFP); + extcon_set_state(priv->edev, EXTCON_USB_HOST, + state == TUSB320_ATTACHED_STATE_DFP); + extcon_set_property(priv->edev, EXTCON_USB, + EXTCON_PROP_USB_TYPEC_POLARITY, + (union extcon_property_value)polarity); + extcon_set_property(priv->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_TYPEC_POLARITY, + (union extcon_property_value)polarity); + extcon_sync(priv->edev, EXTCON_USB); + extcon_sync(priv->edev, EXTCON_USB_HOST); + + regmap_write(priv->regmap, TUSB320_REG9, reg); + + return IRQ_HANDLED; +} + +static const struct regmap_config tusb320_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static int tusb320_extcon_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct tusb320_priv *priv; + int ret; + + priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + priv->dev = &client->dev; + + priv->regmap = devm_regmap_init_i2c(client, &tusb320_regmap_config); + if (IS_ERR(priv->regmap)) + return PTR_ERR(priv->regmap); + + ret = tusb320_check_signature(priv); + if (ret) + return ret; + + priv->edev = devm_extcon_dev_allocate(priv->dev, tusb320_extcon_cable); + if (IS_ERR(priv->edev)) { + dev_err(priv->dev, "failed to allocate extcon device\n"); + return PTR_ERR(priv->edev); + } + + ret = devm_extcon_dev_register(priv->dev, priv->edev); + if (ret < 0) { + dev_err(priv->dev, "failed to register extcon device\n"); + return ret; + } + + extcon_set_property_capability(priv->edev, EXTCON_USB, + EXTCON_PROP_USB_TYPEC_POLARITY); + extcon_set_property_capability(priv->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_TYPEC_POLARITY); + + /* update initial state */ + tusb320_irq_handler(client->irq, priv); + + ret = devm_request_threaded_irq(priv->dev, client->irq, NULL, + tusb320_irq_handler, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + client->name, priv); + + return ret; +} + +static const struct of_device_id tusb320_extcon_dt_match[] = { + { .compatible = "ti,tusb320", }, + { } +}; +MODULE_DEVICE_TABLE(of, tusb320_extcon_dt_match); + +static struct i2c_driver tusb320_extcon_driver = { + .probe = tusb320_extcon_probe, + .driver = { + .name = "extcon-tusb320", + .of_match_table = tusb320_extcon_dt_match, + }, +}; + +static int __init tusb320_init(void) +{ + return i2c_add_driver(&tusb320_extcon_driver); +} +subsys_initcall(tusb320_init); + +static void __exit tusb320_exit(void) +{ + i2c_del_driver(&tusb320_extcon_driver); +} +module_exit(tusb320_exit); + +MODULE_AUTHOR("Michael Auchter <michael.auchter@ni.com>"); +MODULE_DESCRIPTION("TI TUSB320 extcon driver"); +MODULE_LICENSE("GPL v2"); |