Re: [PATCH v3 1/2] media: add SECO cec driver

[Hans Verkuil]

Hi Ettore,

Just a few small things and it is ready to go:

On 10/17/2018 11:31 PM, ektor5 wrote:
> From: Ettore Chimenti <ek5.chimenti@xxxxxxxxx>
> 
> This patch adds support to the CEC device implemented with a STM32
> microcontroller in X86 SECO Boards, including UDOO X86.
> 
> The communication is achieved via Braswell integrated SMBus
> (i2c-i801). The driver use direct access to the PCI addresses, due to
> the limitations of the specific driver in presence of ACPI calls.
> 
> The basic functionalities are tested with success with cec-ctl and
> cec-compliance.
> 
> Inspired by cros-ec-cec implementation, attaches to i915 driver
> cec-notifier.
> 
> Signed-off-by: Ettore Chimenti <ek5.chimenti@xxxxxxxxx>
> ---
>  MAINTAINERS                                |   6 +
>  drivers/media/platform/Kconfig             |  12 +
>  drivers/media/platform/Makefile            |   2 +
>  drivers/media/platform/seco-cec/Makefile   |   1 +
>  drivers/media/platform/seco-cec/seco-cec.c | 699 +++++++++++++++++++++
>  drivers/media/platform/seco-cec/seco-cec.h | 130 ++++
>  6 files changed, 850 insertions(+)
>  create mode 100644 drivers/media/platform/seco-cec/Makefile
>  create mode 100644 drivers/media/platform/seco-cec/seco-cec.c
>  create mode 100644 drivers/media/platform/seco-cec/seco-cec.h
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 4ece30f15777..1062912a5ff4 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -12972,6 +12972,12 @@ L:	sdricohcs-devel@xxxxxxxxxxxxxxxxxxxxx (subscribers-only)
>  S:	Maintained
>  F:	drivers/mmc/host/sdricoh_cs.c
>  
> +SECO BOARDS CEC DRIVER
> +M:	Ettore Chimenti <ek5.chimenti@xxxxxxxxx>
> +S:	Maintained
> +F:	drivers/media/platform/seco-cec/seco-cec.c
> +F:	drivers/media/platform/seco-cec/seco-cec.h
> +
>  SECURE COMPUTING
>  M:	Kees Cook <keescook@xxxxxxxxxxxx>
>  R:	Andy Lutomirski <luto@xxxxxxxxxxxxxx>
> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index 94c1fe0e9787..51cd1fd005e3 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -613,6 +613,18 @@ config VIDEO_TEGRA_HDMI_CEC
>  	 The CEC bus is present in the HDMI connector and enables communication
>  	 between compatible devices.
>  
> +config VIDEO_SECO_CEC
> +	tristate "SECO Boards HDMI CEC driver"
> +	depends on (X86 || IA64) || COMPILE_TEST
> +	depends on PCI && DMI
> +	select CEC_CORE
> +	select CEC_NOTIFIER
> +	help
> +	  This is a driver for SECO Boards integrated CEC interface.
> +	  Selecting it will enable support for this device.
> +	  CEC bus is present in the HDMI connector and enables communication
> +	  between compatible devices.
> +
>  endif #CEC_PLATFORM_DRIVERS
>  
>  menuconfig SDR_PLATFORM_DRIVERS
> diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> index 41322ab65802..5d2b06c4c68a 100644
> --- a/drivers/media/platform/Makefile
> +++ b/drivers/media/platform/Makefile
> @@ -53,6 +53,8 @@ obj-$(CONFIG_VIDEO_TEGRA_HDMI_CEC)	+= tegra-cec/
>  
>  obj-y					+= stm32/
>  
> +obj-$(CONFIG_VIDEO_SECO_CEC)		+= seco-cec/
> +
>  obj-y					+= davinci/
>  
>  obj-$(CONFIG_VIDEO_SH_VOU)		+= sh_vou.o
> diff --git a/drivers/media/platform/seco-cec/Makefile b/drivers/media/platform/seco-cec/Makefile
> new file mode 100644
> index 000000000000..09900b087d02
> --- /dev/null
> +++ b/drivers/media/platform/seco-cec/Makefile
> @@ -0,0 +1 @@
> +obj-y += seco-cec.o
> diff --git a/drivers/media/platform/seco-cec/seco-cec.c b/drivers/media/platform/seco-cec/seco-cec.c
> new file mode 100644
> index 000000000000..9ac9a1f36bc0
> --- /dev/null
> +++ b/drivers/media/platform/seco-cec/seco-cec.c
> @@ -0,0 +1,699 @@
> +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
> +/*
> + * CEC driver for SECO X86 Boards
> + *
> + * Author:  Ettore Chimenti <ek5.chimenti@xxxxxxxxx>
> + * Copyright (C) 2018, SECO Srl.
> + * Copyright (C) 2018, Aidilab Srl.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include <linux/dmi.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/gpio.h>
> +#include <linux/interrupt.h>
> +#include <linux/pci.h>
> +#include <linux/platform_device.h>
> +
> +/* CEC Framework */
> +#include <media/cec.h>
> +
> +#include "seco-cec.h"
> +
> +struct secocec_data {
> +	struct device *dev;
> +	struct platform_device *pdev;
> +	struct cec_adapter *cec_adap;
> +	struct cec_notifier *notifier;
> +	int irq;
> +};
> +
> +#define smb_wr16(cmd, data) smb_word_op(CMD_WORD_DATA, SECOCEC_MICRO_ADDRESS, \
> +					     cmd, data, SMBUS_WRITE, NULL)
> +#define smb_rd16(cmd, res) smb_word_op(CMD_WORD_DATA, SECOCEC_MICRO_ADDRESS, \
> +				       cmd, 0, SMBUS_READ, res)
> +
> +static int smb_word_op(short data_format, u16 slave_addr, u8 cmd, u16 data,
> +		       u8 operation, u16 *result)
> +{
> +	unsigned int count;
> +	short _data_format;
> +	int status = 0;
> +
> +	switch (data_format) {
> +	case CMD_BYTE_DATA:
> +		_data_format = BRA_SMB_CMD_BYTE_DATA;
> +		break;
> +	case CMD_WORD_DATA:
> +		_data_format = BRA_SMB_CMD_WORD_DATA;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	/* Active wait until ready */
> +	for (count = 0; count <= SMBTIMEOUT; ++count) {
> +		if (!(inb(HSTS) & BRA_INUSE_STS))
> +			break;
> +		udelay(SMB_POLL_UDELAY);
> +	}
> +
> +	if (count > SMBTIMEOUT)
> +		/* Reset the lock instead of failing */
> +		outb(0xff, HSTS);
> +
> +	outb(0x00, HCNT);
> +	outb((u8)(slave_addr & 0xfe) | operation, XMIT_SLVA);
> +	outb(cmd, HCMD);
> +	inb(HCNT);
> +
> +	if (operation == SMBUS_WRITE) {
> +		outb((u8)data, HDAT0);
> +		outb((u8)(data >> 8), HDAT1);
> +	}
> +
> +	outb(BRA_START + _data_format, HCNT);
> +
> +	for (count = 0; count <= SMBTIMEOUT; count++) {
> +		if (!(inb(HSTS) & BRA_HOST_BUSY))
> +			break;
> +		udelay(SMB_POLL_UDELAY);
> +	}
> +
> +	if (count > SMBTIMEOUT) {
> +		status = -EBUSY;
> +		goto err;
> +	}
> +
> +	if (inb(HSTS) & BRA_HSTS_ERR_MASK) {
> +		status = -EIO;
> +		goto err;
> +	}
> +
> +	if (operation == SMBUS_READ)
> +		*result = ((inb(HDAT0) & 0xff) + ((inb(HDAT1) & 0xff) << 8));
> +
> +err:
> +	outb(0xff, HSTS);
> +	return status;
> +}
> +
> +static int secocec_adap_enable(struct cec_adapter *adap, bool enable)
> +{
> +	struct secocec_data *cec = cec_get_drvdata(adap);
> +	struct device *dev = cec->dev;
> +	u16 val = 0;
> +	int status;
> +
> +	if (enable) {
> +		/* Clear the status register */
> +		status = smb_rd16(SECOCEC_STATUS_REG_1, &val);
> +		if (status)
> +			goto err;
> +
> +		status = smb_wr16(SECOCEC_STATUS_REG_1, val);
> +		if (status)
> +			goto err;
> +
> +		/* Enable the interrupts */
> +		status = smb_rd16(SECOCEC_ENABLE_REG_1, &val);
> +		if (status)
> +			goto err;
> +
> +		status = smb_wr16(SECOCEC_ENABLE_REG_1,
> +				  val | SECOCEC_ENABLE_REG_1_CEC);
> +		if (status)
> +			goto err;
> +
> +		dev_dbg(dev, "Device enabled");
> +	} else {
> +		/* Clear the status register */
> +		status = smb_rd16(SECOCEC_STATUS_REG_1, &val);
> +		if (status)
> +			goto err;
> +
> +		status = smb_wr16(SECOCEC_STATUS_REG_1, val);
> +		if (status)
> +			goto err;
> +
> +		/* Disable the interrupts */
> +		status = smb_rd16(SECOCEC_ENABLE_REG_1, &val);
> +		if (status)
> +			goto err;
> +
> +		status = smb_wr16(SECOCEC_ENABLE_REG_1, val &
> +				  ~SECOCEC_ENABLE_REG_1_CEC &
> +				  ~SECOCEC_ENABLE_REG_1_IR);
> +		if (status)
> +			goto err;
> +
> +		dev_dbg(dev, "Device disabled");
> +	}
> +
> +	return 0;
> +err:
> +	dev_err(dev, "Adapter setup failed (%d)", status);

Drop the dev_dbg/dev_err lines: the cec module has enough debugging
already.

> +	return status;

This should be:

	return enable ? status : 0;

Disabling shouldn't return an error, it would result in a WARN from
the cec framework.

In fact, I would drop all the error checks in the disable path since they
are ignored anyway.

> +}
> +
> +static int secocec_adap_log_addr(struct cec_adapter *adap, u8 logical_addr)
> +{
> +	u16 enable_val = 0;
> +	int status;

If logical_addr == CEC_LOG_ADDR_INVALID, then this function must not return
an error or the CEC framework will WARN about it.

> +
> +	/* Disable device */
> +	status = smb_rd16(SECOCEC_ENABLE_REG_1, &enable_val);
> +	if (status)
> +		return status;
> +
> +	status = smb_wr16(SECOCEC_ENABLE_REG_1,
> +			  enable_val & ~SECOCEC_ENABLE_REG_1_CEC);
> +	if (status)
> +		return status;
> +
> +	/* Write logical address */
> +	status = smb_wr16(SECOCEC_DEVICE_LA, logical_addr);

So does writing CEC_LOG_ADDR_INVALID (0xff) invalidate all logical
addresses? I see no special code for that. If that is indeed the
case, then you should document this.

> +	if (status)
> +		return status;
> +
> +	/* Re-enable device */
> +	status = smb_wr16(SECOCEC_ENABLE_REG_1,
> +			  enable_val | SECOCEC_ENABLE_REG_1_CEC);
> +	if (status)
> +		return status;
> +
> +	return 0;
> +}
> +
> +static int secocec_adap_transmit(struct cec_adapter *adap, u8 attempts,
> +				 u32 signal_free_time, struct cec_msg *msg)
> +{
> +	struct secocec_data *cec = cec_get_drvdata(adap);
> +	struct device *dev = cec->dev;
> +	u16 payload_len, payload_id_len, destination, val = 0;
> +	u8 *payload_msg;
> +	int status;
> +	u8 i;
> +
> +	/* Device msg len already accounts for header */
> +	payload_id_len = msg->len - 1;
> +
> +	/* Send data length */
> +	status = smb_wr16(SECOCEC_WRITE_DATA_LENGTH, payload_id_len);
> +	if (status)
> +		goto err;
> +
> +	/* Send Operation ID if present */
> +	if (payload_id_len > 0) {
> +		status = smb_wr16(SECOCEC_WRITE_OPERATION_ID, msg->msg[1]);
> +		if (status)
> +			goto err;
> +	}
> +	/* Send data if present */
> +	if (payload_id_len > 1) {
> +		/* Only data; */
> +		payload_len = msg->len - 2;
> +		payload_msg = &msg->msg[2];
> +
> +		/* Copy message into registers */
> +		for (i = 0; i < payload_len; i += 2) {
> +			/* hi byte */
> +			val = payload_msg[i + 1] << 8;
> +
> +			/* lo byte */
> +			val |= payload_msg[i];
> +
> +			status = smb_wr16(SECOCEC_WRITE_DATA_00 + i / 2, val);
> +			if (status)
> +				goto err;
> +		}
> +	}
> +	/* Send msg source/destination and fire msg */
> +	destination = msg->msg[0];
> +	status = smb_wr16(SECOCEC_WRITE_BYTE0, destination);
> +	if (status)
> +		goto err;
> +
> +	return 0;
> +
> +err:
> +	dev_err(dev, "Transmit failed (%d)", status);

You can drop this: the cec module has already debug code for that.

> +	return status;
> +}
> +
> +static int secocec_tx_done(struct cec_adapter *adap, u16 status_val)

Just return void since the return code is ignored anyway.

> +{
> +	int status = 0;
> +
> +	if (status_val & SECOCEC_STATUS_TX_ERROR_MASK) {
> +		if (status_val & SECOCEC_STATUS_TX_NACK_ERROR) {
> +			cec_transmit_attempt_done(adap, CEC_TX_STATUS_NACK);
> +			status = -EAGAIN;
> +		} else {
> +			cec_transmit_attempt_done(adap, CEC_TX_STATUS_ERROR);
> +			status = -EIO;
> +		}
> +	} else {
> +		cec_transmit_attempt_done(adap, CEC_TX_STATUS_OK);
> +	}
> +
> +	/* Reset status reg */
> +	status_val = SECOCEC_STATUS_TX_ERROR_MASK |
> +		SECOCEC_STATUS_MSG_SENT_MASK |
> +		SECOCEC_STATUS_TX_NACK_ERROR;
> +	smb_wr16(SECOCEC_STATUS, status_val);
> +
> +	return status;
> +}
> +
> +static int secocec_rx_done(struct cec_adapter *adap, u16 status_val)
> +{

Ditto.

> +	struct secocec_data *cec = cec_get_drvdata(adap);
> +	struct device *dev = cec->dev;
> +	struct cec_msg msg = { };
> +	bool flag_overflow = false;
> +	u8 payload_len, i = 0;
> +	u8 *payload_msg;
> +	u16 val = 0;
> +	int status;
> +
> +	if (status_val & SECOCEC_STATUS_RX_OVERFLOW_MASK) {
> +		dev_warn(dev, "Received more than 16 bytes. Discarding");

Is it better to just receive the first 16 bytes?

> +		flag_overflow = true;
> +	}
> +
> +	if (status_val & SECOCEC_STATUS_RX_ERROR_MASK) {
> +		dev_warn(dev, "Message received with errors. Discarding");
> +		status = -EIO;
> +		goto rxerr;
> +	}
> +
> +	/* Read message length */
> +	status = smb_rd16(SECOCEC_READ_DATA_LENGTH, &val);
> +	if (status)
> +		goto err;
> +
> +	/* Device msg len already accounts for the header */
> +	msg.len = min(val + 1, CEC_MAX_MSG_SIZE);
> +
> +	/* Read logical address */
> +	status = smb_rd16(SECOCEC_READ_BYTE0, &val);
> +	if (status)
> +		goto err;
> +
> +	/* device stores source LA and destination */
> +	msg.msg[0] = val;
> +
> +	/* Read operation ID */
> +	status = smb_rd16(SECOCEC_READ_OPERATION_ID, &val);
> +	if (status)
> +		goto err;
> +
> +	msg.msg[1] = val;
> +
> +	/* Read data if present */
> +	if (msg.len > 1) {
> +		payload_len = msg.len - 2;
> +		payload_msg = &msg.msg[2];
> +
> +		/* device stores 2 bytes in every 16-bit val */
> +		for (i = 0; i < payload_len; i += 2) {
> +			status = smb_rd16(SECOCEC_READ_DATA_00 + i / 2, &val);
> +			if (status)
> +				goto err;
> +
> +			/* low byte, skipping header */
> +			payload_msg[i] = val & 0x00ff;
> +
> +			/* hi byte */
> +			payload_msg[i + 1] = (val & 0xff00) >> 8;
> +		}
> +	}
> +
> +	cec_received_msg(cec->cec_adap, &msg);
> +
> +	/* Reset status reg */
> +	status_val = SECOCEC_STATUS_MSG_RECEIVED_MASK;
> +	if (flag_overflow)
> +		status_val |= SECOCEC_STATUS_RX_OVERFLOW_MASK;
> +
> +	status = smb_wr16(SECOCEC_STATUS, status_val);
> +	if (status)
> +		goto err;
> +
> +	return 0;
> +
> +rxerr:
> +	/* Reset error reg */
> +	status_val = SECOCEC_STATUS_MSG_RECEIVED_MASK |
> +		SECOCEC_STATUS_RX_ERROR_MASK;
> +	if (flag_overflow)
> +		status_val |= SECOCEC_STATUS_RX_OVERFLOW_MASK;
> +	smb_wr16(SECOCEC_STATUS, status_val);
> +
> +err:
> +	dev_err(dev, "Receive message failed (%d)", status);
> +	return status;
> +}
> +
> +struct cec_adap_ops secocec_cec_adap_ops = {
> +	/* Low-level callbacks */
> +	.adap_enable = secocec_adap_enable,
> +	.adap_log_addr = secocec_adap_log_addr,
> +	.adap_transmit = secocec_adap_transmit,
> +};
> +
> +static irqreturn_t secocec_irq_handler(int irq, void *priv)
> +{
> +	struct secocec_data *cec = priv;
> +	struct device *dev = cec->dev;
> +	u16 status_val, cec_val, val = 0;
> +	int status;
> +
> +	/*  Read status register */
> +	status = smb_rd16(SECOCEC_STATUS_REG_1, &status_val);
> +	if (status)
> +		goto err;
> +
> +	if (status_val & SECOCEC_STATUS_REG_1_CEC) {
> +		/* Read CEC status register */
> +		status = smb_rd16(SECOCEC_STATUS, &cec_val);
> +		if (status)
> +			goto err;
> +
> +		if (cec_val & SECOCEC_STATUS_MSG_RECEIVED_MASK)
> +			secocec_rx_done(cec->cec_adap, cec_val);
> +
> +		if (cec_val & SECOCEC_STATUS_MSG_SENT_MASK)
> +			secocec_tx_done(cec->cec_adap, cec_val);
> +
> +		if ((~cec_val & SECOCEC_STATUS_MSG_SENT_MASK) &&
> +		    (~cec_val & SECOCEC_STATUS_MSG_RECEIVED_MASK))
> +			dev_warn(dev,
> +				 "Message not received or sent, but interrupt fired");

Use dev_warn_once

> +
> +		val = SECOCEC_STATUS_REG_1_CEC;
> +	}
> +
> +	if (status_val & SECOCEC_STATUS_REG_1_IR) {
> +		dev_dbg(dev, "IR RC5 Interrupt Caught");
> +		val |= SECOCEC_STATUS_REG_1_IR;
> +		/* TODO IRDA RX */
> +	}
> +
> +	/*  Reset status register */
> +	status = smb_wr16(SECOCEC_STATUS_REG_1, val);
> +	if (status)
> +		goto err;
> +
> +	return IRQ_HANDLED;
> +
> +err:
> +	dev_err(dev, "IRQ: Read/Write SMBus operation failed (%d)", status);

dev_err_once

This really shouldn't happen, but if it happens, then you don't want
this flooding the log.

> +
> +	/*  Reset status register */
> +	val = SECOCEC_STATUS_REG_1_CEC | SECOCEC_STATUS_REG_1_IR;
> +	smb_wr16(SECOCEC_STATUS_REG_1, val);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +struct cec_dmi_match {
> +	char *sys_vendor;
> +	char *product_name;
> +	char *devname;
> +	char *conn;
> +};
> +
> +static const struct cec_dmi_match secocec_dmi_match_table[] = {
> +	/* UDOO X86 */
> +	{ "SECO", "UDOO x86", "0000:00:02.0", "Port B" },
> +};
> +
> +static int secocec_cec_get_notifier(struct cec_notifier **notify)
> +{
> +	int i;
> +
> +	for (i = 0 ; i < ARRAY_SIZE(secocec_dmi_match_table) ; ++i) {
> +		const struct cec_dmi_match *m = &secocec_dmi_match_table[i];
> +
> +		if (dmi_match(DMI_SYS_VENDOR, m->sys_vendor) &&
> +		    dmi_match(DMI_PRODUCT_NAME, m->product_name)) {
> +			struct device *d;
> +
> +			/* Find the device, bail out if not yet registered */
> +			d = bus_find_device_by_name(&pci_bus_type, NULL,
> +						    m->devname);
> +			if (!d)
> +				return -EPROBE_DEFER;
> +
> +			*notify = cec_notifier_get_conn(d, m->conn);
> +
> +			return 0;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int secocec_acpi_probe(struct secocec_data *sdev)
> +{
> +	struct device *dev = sdev->dev;
> +	struct gpio_desc *gpio;
> +	int irq = 0;
> +
> +	gpio = devm_gpiod_get(dev, NULL, GPIOF_IN);
> +	if (IS_ERR(gpio)) {
> +		dev_err(dev, "Cannot request interrupt gpio");
> +		return PTR_ERR(gpio);
> +	}
> +
> +	irq = gpiod_to_irq(gpio);
> +	if (irq < 0) {
> +		dev_err(dev, "Cannot find valid irq");
> +		return -ENODEV;
> +	}
> +	dev_dbg(dev, "irq-gpio is bound to IRQ %d", irq);
> +
> +	sdev->irq = irq;
> +
> +	return 0;
> +}
> +
> +static int secocec_probe(struct platform_device *pdev)
> +{
> +	struct secocec_data *secocec;
> +	struct device *dev = &pdev->dev;
> +	int ret;
> +	u16 val;
> +
> +	secocec = devm_kzalloc(dev, sizeof(*secocec), GFP_KERNEL);
> +	if (!secocec)
> +		return -ENOMEM;
> +
> +	dev_set_drvdata(dev, secocec);
> +
> +	/* Request SMBus regions */
> +	if (!request_muxed_region(BRA_SMB_BASE_ADDR, 7, "CEC00001")) {
> +		dev_err(dev, "Request memory region failed");
> +		return -ENXIO;
> +	}
> +
> +	secocec->pdev = pdev;
> +	secocec->dev = dev;
> +
> +	if (!has_acpi_companion(dev)) {
> +		dev_dbg(dev, "Cannot find any ACPI companion");
> +		ret = -ENODEV;
> +		goto err;
> +	}
> +
> +	ret = secocec_acpi_probe(secocec);
> +	if (ret) {
> +		dev_err(dev, "Cannot assign gpio to IRQ");
> +		ret = -ENODEV;
> +		goto err;
> +	}
> +
> +	dev_dbg(dev, "IRQ detected at %d", secocec->irq);
> +
> +	/* Firmware version check */
> +	ret = smb_rd16(SECOCEC_VERSION, &val);
> +	if (ret) {
> +		dev_err(dev, "Cannot check fw version");
> +		goto err;
> +	}
> +	if (val < SECOCEC_LATEST_FW) {
> +		dev_err(dev, "CEC Firmware not supported (v.%04x). Use ver > v.%04x",
> +			val, SECOCEC_LATEST_FW);
> +		ret = -EINVAL;
> +		goto err;
> +	}
> +
> +	ret = secocec_cec_get_notifier(&secocec->notifier);
> +	if (ret) {
> +		dev_err(dev, "no CEC notifier available\n");
> +		goto err;
> +	}
> +
> +	ret = devm_request_threaded_irq(dev,
> +					secocec->irq,
> +					NULL,
> +					secocec_irq_handler,
> +					IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> +					dev_name(&pdev->dev), secocec);
> +
> +	if (ret) {
> +		dev_err(dev, "Cannot request IRQ %d", secocec->irq);
> +		ret = -EIO;
> +		goto err;
> +	}
> +
> +	/* Allocate CEC adapter */
> +	secocec->cec_adap = cec_allocate_adapter(&secocec_cec_adap_ops,
> +						 secocec,
> +						 dev_name(dev),
> +						 CEC_CAP_DEFAULTS,
> +						 SECOCEC_MAX_ADDRS);
> +
> +	if (IS_ERR(secocec->cec_adap)) {
> +		ret = PTR_ERR(secocec->cec_adap);
> +		goto err;
> +	}
> +
> +	ret = cec_register_adapter(secocec->cec_adap, dev);
> +	if (ret)
> +		goto err_delete_adapter;
> +
> +	if (secocec->notifier)
> +		cec_register_cec_notifier(secocec->cec_adap, secocec->notifier);
> +
> +	platform_set_drvdata(pdev, secocec);
> +
> +	dev_dbg(dev, "Device registered");
> +
> +	return ret;
> +
> +err_delete_adapter:
> +	cec_delete_adapter(secocec->cec_adap);
> +err:
> +	dev_err(dev, "%s device probe failed\n", dev_name(dev));
> +
> +	return ret;
> +}
> +
> +static int secocec_remove(struct platform_device *pdev)
> +{
> +	struct secocec_data *secocec = platform_get_drvdata(pdev);
> +
> +	cec_unregister_adapter(secocec->cec_adap);
> +
> +	if (secocec->notifier)
> +		cec_notifier_put(secocec->notifier);
> +
> +	release_region(BRA_SMB_BASE_ADDR, 7);
> +
> +	dev_dbg(&pdev->dev, "CEC device removed");
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int secocec_suspend(struct device *dev)
> +{
> +	int status;
> +	u16 val;
> +
> +	dev_dbg(dev, "Device going to suspend, disabling");
> +
> +	/* Clear the status register */
> +	status = smb_rd16(SECOCEC_STATUS_REG_1, &val);
> +	if (status)
> +		goto err;
> +
> +	status = smb_wr16(SECOCEC_STATUS_REG_1, val);
> +	if (status)
> +		goto err;
> +
> +	/* Disable the interrupts */
> +	status = smb_rd16(SECOCEC_ENABLE_REG_1, &val);
> +	if (status)
> +		goto err;
> +
> +	status = smb_wr16(SECOCEC_ENABLE_REG_1, val &
> +			  ~SECOCEC_ENABLE_REG_1_CEC & ~SECOCEC_ENABLE_REG_1_IR);
> +	if (status)
> +		goto err;
> +
> +	return 0;
> +
> +err:
> +	dev_err(dev, "Suspend failed (err: %d)", status);
> +	return status;
> +}
> +
> +static int secocec_resume(struct device *dev)
> +{
> +	int status;
> +	u16 val;
> +
> +	dev_dbg(dev, "Resuming device from suspend");
> +
> +	/* Clear the status register */
> +	status = smb_rd16(SECOCEC_STATUS_REG_1, &val);
> +	if (status)
> +		goto err;
> +
> +	status = smb_wr16(SECOCEC_STATUS_REG_1, val);
> +	if (status)
> +		goto err;
> +
> +	/* Enable the interrupts */
> +	status = smb_rd16(SECOCEC_ENABLE_REG_1, &val);
> +	if (status)
> +		goto err;
> +
> +	status = smb_wr16(SECOCEC_ENABLE_REG_1, val | SECOCEC_ENABLE_REG_1_CEC);
> +	if (status)
> +		goto err;
> +
> +	dev_dbg(dev, "Device resumed from suspend");
> +
> +	return 0;
> +
> +err:
> +	dev_err(dev, "Resume failed (err: %d)", status);
> +	return status;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(secocec_pm_ops, secocec_suspend, secocec_resume);
> +#define SECOCEC_PM_OPS (&secocec_pm_ops)
> +#else
> +#define SECOCEC_PM_OPS NULL
> +#endif
> +
> +#ifdef CONFIG_ACPI
> +static const struct acpi_device_id secocec_acpi_match[] = {
> +	{"CEC00001", 0},
> +	{},
> +};
> +
> +MODULE_DEVICE_TABLE(acpi, secocec_acpi_match);
> +#endif
> +
> +static struct platform_driver secocec_driver = {
> +	.driver = {
> +		   .name = SECOCEC_DEV_NAME,
> +		   .acpi_match_table = ACPI_PTR(secocec_acpi_match),
> +		   .pm = SECOCEC_PM_OPS,
> +	},
> +	.probe = secocec_probe,
> +	.remove = secocec_remove,
> +};
> +
> +module_platform_driver(secocec_driver);
> +
> +MODULE_DESCRIPTION("SECO CEC X86 Driver");
> +MODULE_AUTHOR("Ettore Chimenti <ek5.chimenti@xxxxxxxxx>");
> +MODULE_LICENSE("Dual BSD/GPL");
> diff --git a/drivers/media/platform/seco-cec/seco-cec.h b/drivers/media/platform/seco-cec/seco-cec.h
> new file mode 100644
> index 000000000000..93020900935e
> --- /dev/null
> +++ b/drivers/media/platform/seco-cec/seco-cec.h
> @@ -0,0 +1,130 @@
> +/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
> +/*
> + * SECO X86 Boards CEC register defines
> + *
> + * Author:  Ettore Chimenti <ek5.chimenti@xxxxxxxxx>
> + * Copyright (C) 2018, SECO Srl.
> + * Copyright (C) 2018, Aidilab Srl.
> + */
> +
> +#ifndef __SECO_CEC_H__
> +#define __SECO_CEC_H__
> +
> +#define SECOCEC_MAX_ADDRS		1
> +#define SECOCEC_DEV_NAME		"secocec"
> +#define SECOCEC_LATEST_FW		0x0f0b
> +
> +#define SMBTIMEOUT			0xffff
> +#define SMB_POLL_UDELAY			10
> +
> +#define SMBUS_WRITE			0
> +#define SMBUS_READ			1
> +
> +#define CMD_BYTE_DATA			0
> +#define CMD_WORD_DATA			1
> +
> +/*
> + * SMBus definitons for Braswell
> + */
> +
> +#define BRA_DONE_STATUS			BIT(7)
> +#define BRA_INUSE_STS			BIT(6)
> +#define BRA_FAILED_OP			BIT(4)
> +#define BRA_BUS_ERR			BIT(3)
> +#define BRA_DEV_ERR			BIT(2)
> +#define BRA_INTR			BIT(1)
> +#define BRA_HOST_BUSY			BIT(0)
> +#define BRA_HSTS_ERR_MASK   (BRA_FAILED_OP | BRA_BUS_ERR | BRA_DEV_ERR)
> +
> +#define BRA_PEC_EN			BIT(7)
> +#define BRA_START			BIT(6)
> +#define BRA_LAST__BYTE			BIT(5)
> +#define BRA_INTREN			BIT(0)
> +#define BRA_SMB_CMD			(7 << 2)
> +#define BRA_SMB_CMD_QUICK		(0 << 2)
> +#define BRA_SMB_CMD_BYTE		(1 << 2)
> +#define BRA_SMB_CMD_BYTE_DATA		(2 << 2)
> +#define BRA_SMB_CMD_WORD_DATA		(3 << 2)
> +#define BRA_SMB_CMD_PROCESS_CALL	(4 << 2)
> +#define BRA_SMB_CMD_BLOCK		(5 << 2)
> +#define BRA_SMB_CMD_I2CREAD		(6 << 2)
> +#define BRA_SMB_CMD_BLOCK_PROCESS	(7 << 2)
> +
> +#define BRA_SMB_BASE_ADDR  0x2040
> +#define HSTS               (BRA_SMB_BASE_ADDR + 0)
> +#define HCNT               (BRA_SMB_BASE_ADDR + 2)
> +#define HCMD               (BRA_SMB_BASE_ADDR + 3)
> +#define XMIT_SLVA          (BRA_SMB_BASE_ADDR + 4)
> +#define HDAT0              (BRA_SMB_BASE_ADDR + 5)
> +#define HDAT1              (BRA_SMB_BASE_ADDR + 6)
> +
> +/*
> + * Microcontroller Address
> + */
> +
> +#define SECOCEC_MICRO_ADDRESS		0x40
> +
> +/*
> + * STM32 SMBus Registers
> + */
> +
> +#define SECOCEC_VERSION			0x00
> +#define SECOCEC_ENABLE_REG_1		0x01
> +#define SECOCEC_ENABLE_REG_2		0x02
> +#define SECOCEC_STATUS_REG_1		0x03
> +#define SECOCEC_STATUS_REG_2		0x04
> +
> +#define SECOCEC_STATUS			0x28
> +#define SECOCEC_DEVICE_LA		0x29
> +#define SECOCEC_READ_OPERATION_ID	0x2a
> +#define SECOCEC_READ_DATA_LENGTH	0x2b
> +#define SECOCEC_READ_DATA_00		0x2c
> +#define SECOCEC_READ_DATA_02		0x2d
> +#define SECOCEC_READ_DATA_04		0x2e
> +#define SECOCEC_READ_DATA_06		0x2f
> +#define SECOCEC_READ_DATA_08		0x30
> +#define SECOCEC_READ_DATA_10		0x31
> +#define SECOCEC_READ_DATA_12		0x32
> +#define SECOCEC_READ_BYTE0		0x33
> +#define SECOCEC_WRITE_OPERATION_ID	0x34
> +#define SECOCEC_WRITE_DATA_LENGTH	0x35
> +#define SECOCEC_WRITE_DATA_00		0x36
> +#define SECOCEC_WRITE_DATA_02		0x37
> +#define SECOCEC_WRITE_DATA_04		0x38
> +#define SECOCEC_WRITE_DATA_06		0x39
> +#define SECOCEC_WRITE_DATA_08		0x3a
> +#define SECOCEC_WRITE_DATA_10		0x3b
> +#define SECOCEC_WRITE_DATA_12		0x3c
> +#define SECOCEC_WRITE_BYTE0		0x3d
> +
> +#define SECOCEC_IR_READ_DATA		0x3e
> +
> +/*
> + * Enabling register
> + */
> +
> +#define SECOCEC_ENABLE_REG_1_CEC		0x1000
> +#define SECOCEC_ENABLE_REG_1_IR			0x2000
> +#define SECOCEC_ENABLE_REG_1_IR_PASSTHROUGH	0x4000
> +
> +/*
> + * Status register
> + */
> +
> +#define SECOCEC_STATUS_REG_1_CEC	SECOCEC_ENABLE_REG_1_CEC
> +#define SECOCEC_STATUS_REG_1_IR		SECOCEC_ENABLE_REG_1_IR
> +#define SECOCEC_STATUS_REG_1_IR_PASSTHR	SECOCEC_ENABLE_REG_1_IR_PASSTHR
> +
> +/*
> + * Status data
> + */
> +
> +#define SECOCEC_STATUS_MSG_RECEIVED_MASK	BIT(0)
> +#define SECOCEC_STATUS_RX_ERROR_MASK		BIT(1)
> +#define SECOCEC_STATUS_MSG_SENT_MASK		BIT(2)
> +#define SECOCEC_STATUS_TX_ERROR_MASK		BIT(3)
> +
> +#define SECOCEC_STATUS_TX_NACK_ERROR		BIT(4)
> +#define SECOCEC_STATUS_RX_OVERFLOW_MASK		BIT(5)
> +
> +#endif /* __SECO_CEC_H__ */
> 

Regards,

	Hans