diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/typec/ucsi/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/usb/typec/ucsi/Makefile | 2 | ||||
| -rw-r--r-- | drivers/usb/typec/ucsi/ucsi_ccg.c | 307 | 
3 files changed, 319 insertions, 0 deletions
| diff --git a/drivers/usb/typec/ucsi/Kconfig b/drivers/usb/typec/ucsi/Kconfig index e36d6c73c4a4..78118883f96c 100644 --- a/drivers/usb/typec/ucsi/Kconfig +++ b/drivers/usb/typec/ucsi/Kconfig @@ -23,6 +23,16 @@ config TYPEC_UCSI  if TYPEC_UCSI +config UCSI_CCG +	tristate "UCSI Interface Driver for Cypress CCGx" +	depends on I2C +	help +	  This driver enables UCSI support on platforms that expose a +	  Cypress CCGx Type-C controller over I2C interface. + +	  To compile the driver as a module, choose M here: the module will be +	  called ucsi_ccg. +  config UCSI_ACPI  	tristate "UCSI ACPI Interface Driver"  	depends on ACPI diff --git a/drivers/usb/typec/ucsi/Makefile b/drivers/usb/typec/ucsi/Makefile index 7afbea512207..2f4900b26210 100644 --- a/drivers/usb/typec/ucsi/Makefile +++ b/drivers/usb/typec/ucsi/Makefile @@ -8,3 +8,5 @@ typec_ucsi-y			:= ucsi.o  typec_ucsi-$(CONFIG_TRACING)	+= trace.o  obj-$(CONFIG_UCSI_ACPI)		+= ucsi_acpi.o + +obj-$(CONFIG_UCSI_CCG)		+= ucsi_ccg.o diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c new file mode 100644 index 000000000000..de8a43bdff68 --- /dev/null +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c @@ -0,0 +1,307 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * UCSI driver for Cypress CCGx Type-C controller + * + * Copyright (C) 2017-2018 NVIDIA Corporation. All rights reserved. + * Author: Ajay Gupta <ajayg@nvidia.com> + * + * Some code borrowed from drivers/usb/typec/ucsi/ucsi_acpi.c + */ +#include <linux/acpi.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/platform_device.h> + +#include <asm/unaligned.h> +#include "ucsi.h" + +struct ucsi_ccg { +	struct device *dev; +	struct ucsi *ucsi; +	struct ucsi_ppm ppm; +	struct i2c_client *client; +}; + +#define CCGX_RAB_INTR_REG			0x06 +#define CCGX_RAB_UCSI_CONTROL			0x39 +#define CCGX_RAB_UCSI_CONTROL_START		BIT(0) +#define CCGX_RAB_UCSI_CONTROL_STOP		BIT(1) +#define CCGX_RAB_UCSI_DATA_BLOCK(offset)	(0xf000 | ((offset) & 0xff)) + +static int ccg_read(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len) +{ +	struct i2c_client *client = uc->client; +	const struct i2c_adapter_quirks *quirks = client->adapter->quirks; +	unsigned char buf[2]; +	struct i2c_msg msgs[] = { +		{ +			.addr	= client->addr, +			.flags  = 0x0, +			.len	= sizeof(buf), +			.buf	= buf, +		}, +		{ +			.addr	= client->addr, +			.flags  = I2C_M_RD, +			.buf	= data, +		}, +	}; +	u32 rlen, rem_len = len, max_read_len = len; +	int status; + +	/* check any max_read_len limitation on i2c adapter */ +	if (quirks && quirks->max_read_len) +		max_read_len = quirks->max_read_len; + +	while (rem_len > 0) { +		msgs[1].buf = &data[len - rem_len]; +		rlen = min_t(u16, rem_len, max_read_len); +		msgs[1].len = rlen; +		put_unaligned_le16(rab, buf); +		status = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); +		if (status < 0) { +			dev_err(uc->dev, "i2c_transfer failed %d\n", status); +			return status; +		} +		rab += rlen; +		rem_len -= rlen; +	} + +	return 0; +} + +static int ccg_write(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len) +{ +	struct i2c_client *client = uc->client; +	unsigned char *buf; +	struct i2c_msg msgs[] = { +		{ +			.addr	= client->addr, +			.flags  = 0x0, +		} +	}; +	int status; + +	buf = kzalloc(len + sizeof(rab), GFP_KERNEL); +	if (!buf) +		return -ENOMEM; + +	put_unaligned_le16(rab, buf); +	memcpy(buf + sizeof(rab), data, len); + +	msgs[0].len = len + sizeof(rab); +	msgs[0].buf = buf; + +	status = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); +	if (status < 0) { +		dev_err(uc->dev, "i2c_transfer failed %d\n", status); +		kfree(buf); +		return status; +	} + +	kfree(buf); +	return 0; +} + +static int ucsi_ccg_init(struct ucsi_ccg *uc) +{ +	unsigned int count = 10; +	u8 data; +	int status; + +	data = CCGX_RAB_UCSI_CONTROL_STOP; +	status = ccg_write(uc, CCGX_RAB_UCSI_CONTROL, &data, sizeof(data)); +	if (status < 0) +		return status; + +	data = CCGX_RAB_UCSI_CONTROL_START; +	status = ccg_write(uc, CCGX_RAB_UCSI_CONTROL, &data, sizeof(data)); +	if (status < 0) +		return status; + +	/* +	 * Flush CCGx RESPONSE queue by acking interrupts. Above ucsi control +	 * register write will push response which must be cleared. +	 */ +	do { +		status = ccg_read(uc, CCGX_RAB_INTR_REG, &data, sizeof(data)); +		if (status < 0) +			return status; + +		if (!data) +			return 0; + +		status = ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data)); +		if (status < 0) +			return status; + +		usleep_range(10000, 11000); +	} while (--count); + +	return -ETIMEDOUT; +} + +static int ucsi_ccg_send_data(struct ucsi_ccg *uc) +{ +	u8 *ppm = (u8 *)uc->ppm.data; +	int status; +	u16 rab; + +	rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, message_out)); +	status = ccg_write(uc, rab, ppm + +			   offsetof(struct ucsi_data, message_out), +			   sizeof(uc->ppm.data->message_out)); +	if (status < 0) +		return status; + +	rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, ctrl)); +	return ccg_write(uc, rab, ppm + offsetof(struct ucsi_data, ctrl), +			 sizeof(uc->ppm.data->ctrl)); +} + +static int ucsi_ccg_recv_data(struct ucsi_ccg *uc) +{ +	u8 *ppm = (u8 *)uc->ppm.data; +	int status; +	u16 rab; + +	rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, cci)); +	status = ccg_read(uc, rab, ppm + offsetof(struct ucsi_data, cci), +			  sizeof(uc->ppm.data->cci)); +	if (status < 0) +		return status; + +	rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, message_in)); +	return ccg_read(uc, rab, ppm + offsetof(struct ucsi_data, message_in), +			sizeof(uc->ppm.data->message_in)); +} + +static int ucsi_ccg_ack_interrupt(struct ucsi_ccg *uc) +{ +	int status; +	unsigned char data; + +	status = ccg_read(uc, CCGX_RAB_INTR_REG, &data, sizeof(data)); +	if (status < 0) +		return status; + +	return ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data)); +} + +static int ucsi_ccg_sync(struct ucsi_ppm *ppm) +{ +	struct ucsi_ccg *uc = container_of(ppm, struct ucsi_ccg, ppm); +	int status; + +	status = ucsi_ccg_recv_data(uc); +	if (status < 0) +		return status; + +	/* ack interrupt to allow next command to run */ +	return ucsi_ccg_ack_interrupt(uc); +} + +static int ucsi_ccg_cmd(struct ucsi_ppm *ppm, struct ucsi_control *ctrl) +{ +	struct ucsi_ccg *uc = container_of(ppm, struct ucsi_ccg, ppm); + +	ppm->data->ctrl.raw_cmd = ctrl->raw_cmd; +	return ucsi_ccg_send_data(uc); +} + +static irqreturn_t ccg_irq_handler(int irq, void *data) +{ +	struct ucsi_ccg *uc = data; + +	ucsi_notify(uc->ucsi); + +	return IRQ_HANDLED; +} + +static int ucsi_ccg_probe(struct i2c_client *client, +			  const struct i2c_device_id *id) +{ +	struct device *dev = &client->dev; +	struct ucsi_ccg *uc; +	int status; +	u16 rab; + +	uc = devm_kzalloc(dev, sizeof(*uc), GFP_KERNEL); +	if (!uc) +		return -ENOMEM; + +	uc->ppm.data = devm_kzalloc(dev, sizeof(struct ucsi_data), GFP_KERNEL); +	if (!uc->ppm.data) +		return -ENOMEM; + +	uc->ppm.cmd = ucsi_ccg_cmd; +	uc->ppm.sync = ucsi_ccg_sync; +	uc->dev = dev; +	uc->client = client; + +	/* reset ccg device and initialize ucsi */ +	status = ucsi_ccg_init(uc); +	if (status < 0) { +		dev_err(uc->dev, "ucsi_ccg_init failed - %d\n", status); +		return status; +	} + +	status = devm_request_threaded_irq(dev, client->irq, NULL, +					   ccg_irq_handler, +					   IRQF_ONESHOT | IRQF_TRIGGER_HIGH, +					   dev_name(dev), uc); +	if (status < 0) { +		dev_err(uc->dev, "request_threaded_irq failed - %d\n", status); +		return status; +	} + +	uc->ucsi = ucsi_register_ppm(dev, &uc->ppm); +	if (IS_ERR(uc->ucsi)) { +		dev_err(uc->dev, "ucsi_register_ppm failed\n"); +		return PTR_ERR(uc->ucsi); +	} + +	rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, version)); +	status = ccg_read(uc, rab, (u8 *)(uc->ppm.data) + +			  offsetof(struct ucsi_data, version), +			  sizeof(uc->ppm.data->version)); +	if (status < 0) { +		ucsi_unregister_ppm(uc->ucsi); +		return status; +	} + +	i2c_set_clientdata(client, uc); +	return 0; +} + +static int ucsi_ccg_remove(struct i2c_client *client) +{ +	struct ucsi_ccg *uc = i2c_get_clientdata(client); + +	ucsi_unregister_ppm(uc->ucsi); + +	return 0; +} + +static const struct i2c_device_id ucsi_ccg_device_id[] = { +	{"ccgx-ucsi", 0}, +	{} +}; +MODULE_DEVICE_TABLE(i2c, ucsi_ccg_device_id); + +static struct i2c_driver ucsi_ccg_driver = { +	.driver = { +		.name = "ucsi_ccg", +	}, +	.probe = ucsi_ccg_probe, +	.remove = ucsi_ccg_remove, +	.id_table = ucsi_ccg_device_id, +}; + +module_i2c_driver(ucsi_ccg_driver); + +MODULE_AUTHOR("Ajay Gupta <ajayg@nvidia.com>"); +MODULE_DESCRIPTION("UCSI driver for Cypress CCGx Type-C controller"); +MODULE_LICENSE("GPL v2"); | 
