diff --git a/drivers/usb/typec/ucsi/Kconfig b/drivers/usb/typec/ucsi/Kconfig index 5e9b37b3f25e..8f9c4b9f31f7 100644 --- a/drivers/usb/typec/ucsi/Kconfig +++ b/drivers/usb/typec/ucsi/Kconfig @@ -48,4 +48,14 @@ config UCSI_ACPI To compile the driver as a module, choose M here: the module will be called ucsi_acpi +config UCSI_STM32G0 + tristate "UCSI Interface Driver for STM32G0" + depends on I2C + help + This driver enables UCSI support on platforms that expose a STM32G0 + Type-C controller over I2C interface. + + To compile the driver as a module, choose M here: the module will be + called ucsi_stm32g0. + endif diff --git a/drivers/usb/typec/ucsi/Makefile b/drivers/usb/typec/ucsi/Makefile index 8a8eb5cb8e0f..480d533d762f 100644 --- a/drivers/usb/typec/ucsi/Makefile +++ b/drivers/usb/typec/ucsi/Makefile @@ -17,3 +17,4 @@ endif obj-$(CONFIG_UCSI_ACPI) += ucsi_acpi.o obj-$(CONFIG_UCSI_CCG) += ucsi_ccg.o +obj-$(CONFIG_UCSI_STM32G0) += ucsi_stm32g0.o diff --git a/drivers/usb/typec/ucsi/ucsi_stm32g0.c b/drivers/usb/typec/ucsi/ucsi_stm32g0.c new file mode 100644 index 000000000000..e3965cbff058 --- /dev/null +++ b/drivers/usb/typec/ucsi/ucsi_stm32g0.c @@ -0,0 +1,264 @@ +// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +/* + * UCSI driver for STMicroelectronics STM32G0 Type-C PD controller + * + * Copyright (C) 2022, STMicroelectronics - All Rights Reserved + * Author: Fabrice Gasnier . + */ + +#include +#include +#include +#include + +#include "ucsi.h" + +struct ucsi_stm32g0 { + struct i2c_client *client; + struct completion complete; + struct device *dev; + unsigned long flags; + struct ucsi *ucsi; + bool suspended; + bool wakeup_event; +}; + +static int ucsi_stm32g0_read(struct ucsi *ucsi, unsigned int offset, void *val, size_t len) +{ + struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); + struct i2c_client *client = g0->client; + u8 reg = offset; + struct i2c_msg msg[] = { + { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = ®, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = len, + .buf = val, + }, + }; + int ret; + + ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); + if (ret != ARRAY_SIZE(msg)) { + dev_err(g0->dev, "i2c read %02x, %02x error: %d\n", client->addr, reg, ret); + + return ret < 0 ? ret : -EIO; + } + + return 0; +} + +static int ucsi_stm32g0_async_write(struct ucsi *ucsi, unsigned int offset, const void *val, + size_t len) +{ + struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); + struct i2c_client *client = g0->client; + struct i2c_msg msg[] = { + { + .addr = client->addr, + .flags = 0, + } + }; + unsigned char *buf; + int ret; + + buf = kmalloc(len + 1, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + buf[0] = offset; + memcpy(&buf[1], val, len); + msg[0].len = len + 1; + msg[0].buf = buf; + + ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); + kfree(buf); + if (ret != ARRAY_SIZE(msg)) { + dev_err(g0->dev, "i2c write %02x, %02x error: %d\n", client->addr, offset, ret); + + return ret < 0 ? ret : -EIO; + } + + return 0; +} + +static int ucsi_stm32g0_sync_write(struct ucsi *ucsi, unsigned int offset, const void *val, + size_t len) +{ + struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); + int ret; + + set_bit(COMMAND_PENDING, &g0->flags); + + ret = ucsi_stm32g0_async_write(ucsi, offset, val, len); + if (ret) + goto out_clear_bit; + + if (!wait_for_completion_timeout(&g0->complete, msecs_to_jiffies(5000))) + ret = -ETIMEDOUT; + +out_clear_bit: + clear_bit(COMMAND_PENDING, &g0->flags); + + return ret; +} + +static irqreturn_t ucsi_stm32g0_irq_handler(int irq, void *data) +{ + struct ucsi_stm32g0 *g0 = data; + u32 cci; + int ret; + + if (g0->suspended) + g0->wakeup_event = true; + + ret = ucsi_stm32g0_read(g0->ucsi, UCSI_CCI, &cci, sizeof(cci)); + if (ret) + return IRQ_NONE; + + if (UCSI_CCI_CONNECTOR(cci)) + ucsi_connector_change(g0->ucsi, UCSI_CCI_CONNECTOR(cci)); + + if (test_bit(COMMAND_PENDING, &g0->flags) && + cci & (UCSI_CCI_ACK_COMPLETE | UCSI_CCI_COMMAND_COMPLETE)) + complete(&g0->complete); + + return IRQ_HANDLED; +} + +static const struct ucsi_operations ucsi_stm32g0_ops = { + .read = ucsi_stm32g0_read, + .sync_write = ucsi_stm32g0_sync_write, + .async_write = ucsi_stm32g0_async_write, +}; + +static int ucsi_stm32g0_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct ucsi_stm32g0 *g0; + int ret; + + g0 = devm_kzalloc(dev, sizeof(*g0), GFP_KERNEL); + if (!g0) + return -ENOMEM; + + g0->dev = dev; + g0->client = client; + init_completion(&g0->complete); + i2c_set_clientdata(client, g0); + + g0->ucsi = ucsi_create(dev, &ucsi_stm32g0_ops); + if (IS_ERR(g0->ucsi)) + return PTR_ERR(g0->ucsi); + + ucsi_set_drvdata(g0->ucsi, g0); + + /* Request alert interrupt */ + ret = request_threaded_irq(client->irq, NULL, ucsi_stm32g0_irq_handler, IRQF_ONESHOT, + dev_name(&client->dev), g0); + if (ret) { + dev_err_probe(dev, ret, "request IRQ failed\n"); + goto destroy; + } + + ret = ucsi_register(g0->ucsi); + if (ret) { + dev_err_probe(dev, ret, "ucsi_register failed\n"); + goto freeirq; + } + + return 0; + +freeirq: + free_irq(client->irq, g0); +destroy: + ucsi_destroy(g0->ucsi); + + return ret; +} + +static int ucsi_stm32g0_remove(struct i2c_client *client) +{ + struct ucsi_stm32g0 *g0 = i2c_get_clientdata(client); + + ucsi_unregister(g0->ucsi); + free_irq(client->irq, g0); + ucsi_destroy(g0->ucsi); + + return 0; +} + +static int ucsi_stm32g0_suspend(struct device *dev) +{ + struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev); + struct i2c_client *client = g0->client; + + /* Keep the interrupt disabled until the i2c bus has been resumed */ + disable_irq(client->irq); + + g0->suspended = true; + g0->wakeup_event = false; + + if (device_may_wakeup(dev) || device_wakeup_path(dev)) + enable_irq_wake(client->irq); + + return 0; +} + +static int ucsi_stm32g0_resume(struct device *dev) +{ + struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev); + struct i2c_client *client = g0->client; + + if (device_may_wakeup(dev) || device_wakeup_path(dev)) + disable_irq_wake(client->irq); + + enable_irq(client->irq); + + /* Enforce any pending handler gets called to signal a wakeup_event */ + synchronize_irq(client->irq); + + if (g0->wakeup_event) + pm_wakeup_event(g0->dev, 0); + + g0->suspended = false; + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(ucsi_stm32g0_pm_ops, ucsi_stm32g0_suspend, ucsi_stm32g0_resume); + +static const struct of_device_id __maybe_unused ucsi_stm32g0_typec_of_match[] = { + { .compatible = "st,stm32g0-typec" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ucsi_stm32g0_typec_of_match); + +static const struct i2c_device_id ucsi_stm32g0_typec_i2c_devid[] = { + {"stm32g0-typec", 0}, + {}, +}; +MODULE_DEVICE_TABLE(i2c, ucsi_stm32g0_typec_i2c_devid); + +static struct i2c_driver ucsi_stm32g0_i2c_driver = { + .driver = { + .name = "ucsi-stm32g0-i2c", + .of_match_table = of_match_ptr(ucsi_stm32g0_typec_of_match), + .pm = pm_sleep_ptr(&ucsi_stm32g0_pm_ops), + }, + .probe = ucsi_stm32g0_probe, + .remove = ucsi_stm32g0_remove, + .id_table = ucsi_stm32g0_typec_i2c_devid +}; +module_i2c_driver(ucsi_stm32g0_i2c_driver); + +MODULE_AUTHOR("Fabrice Gasnier "); +MODULE_DESCRIPTION("STMicroelectronics STM32G0 Type-C controller"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_ALIAS("platform:ucsi-stm32g0");