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

From: Hans Verkuil
Date: Thu Oct 04 2018 - 07:53:10 EST


On 10/03/18 11:35, jacopo mondi wrote:
> Hi Ettore,
> thanks for the patch.
>
> A few comments below, please have a look...
>
> On Tue, Oct 02, 2018 at 06:59:55PM +0200, 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 | 11 +
>> drivers/media/platform/Makefile | 4 +
>> drivers/media/platform/seco-cec/Makefile | 1 +
>> drivers/media/platform/seco-cec/seco-cec.c | 729 +++++++++++++++++++++
>> drivers/media/platform/seco-cec/seco-cec.h | 132 ++++
>> 6 files changed, 883 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..f477764b902a 100644
>> --- a/drivers/media/platform/Kconfig
>> +++ b/drivers/media/platform/Kconfig
>> @@ -613,6 +613,17 @@ 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
>> + select CEC_CORE
>> + select CEC_NOTIFIER
>> + help
>> + This is a driver for SECO Boards integrated CEC interface. It uses the
>> + generic CEC framework interface.
>
> Is it worth mentioning the software framework used for implementing the driver?
> Anyway, I see this is common to most of the CEC drivers here, so I
> guess it is fine

It's not worth mentioning :-)

Not sure how and why that phrase crept into cec driver Kconfigs.

>
>> + 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..cc7365c787ba 100644
>> --- a/drivers/media/platform/Makefile
>> +++ b/drivers/media/platform/Makefile
>> @@ -53,6 +53,10 @@ obj-$(CONFIG_VIDEO_TEGRA_HDMI_CEC) += tegra-cec/
>>
>> obj-y += stm32/
>>
>> +obj-$(CONFIG_VIDEO_SECO_CEC) += seco-cec/
>> +
>> +obj-y += blackfin/
>> +
>
> Ups! Is this a leftover from some BSP code? It breaks the build on
> media-tree master (and I guess on master too)
>
>> obj-y += davinci/
>>
>> obj-$(CONFIG_VIDEO_SH_VOU) += sh_vou.o
>> diff --git a/drivers/media/platform/seco-cec/Makefile b/drivers/media/platform/seco-cec/Makefile
>> new file mode 100644
>> index 000000000000..a3f2c6bd3ac0
>> --- /dev/null
>> +++ b/drivers/media/platform/seco-cec/Makefile
>> @@ -0,0 +1 @@
>> +obj-$(CONFIG_VIDEO_SECO_CEC) += seco-cec.o
>
> This can simply be obj-y as you parse this makefile entry
> conditionally to the presence of the CONFIG_VIDEO_SECO_CEC symbol
>
>> 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..ba3b7c144a87
>> --- /dev/null
>> +++ b/drivers/media/platform/seco-cec/seco-cec.c
>> @@ -0,0 +1,729 @@
>> +// SPDX-License-Identifier: GPL-2.0 AND BSD-3-Clause
>
> Just make sure the AND is what you want (I only see OR clauses in
> drivers/ code). See Documentation/process/license-rules.rst
>
>> +/*
>> + *
> Nit: empty comment line
>> + * CEC driver for SECO X86 Boards
>> + *
>> + * Author: Ettore Chimenti <ek5.chimenti@xxxxxxxxx>
>> + * Copyright (C) 2018, SECO Srl.
>> + * Copyright (C) 2018, Aidilab Srl.
>> + *
> Nit: empty comment line
>> + */
>> +
>> +#include <linux/interrupt.h>
>> +#include <linux/gpio.h>
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/acpi.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/delay.h>
>> +#include <linux/pci.h>
>> +#include <linux/dmi.h>
>> +
>> +/* CEC Framework */
>> +#include <media/cec.h>
>> +
>> +#include "seco-cec.h"
>
> I would question why a header file is needed as it is not included by
> anything else
>
>> +
>> +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 ret, status = 0;
>
> In the rest of the function ret is used only once, and you can use
> status in its place. Please drop one of the two.
>
>> +
>> + 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);
>> + pr_warn("%s: SMBTIMEOUT\n", __func__);
>
> No pr_debug/pr_warn if possible, please.
>
>> + }
>> +
>> + 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);
>> + pr_debug("%s: WRITE (0x%02x - count %05d): 0x%04x\n",
>> + __func__, cmd, count, data);
>> + }
>> +
>> + 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) {
>> + pr_debug("%s: SMBTIMEOUT_1\n", __func__);
>> + status = -EBUSY;
>> + goto err;
>> + }
>> +
>> + ret = inb(HSTS);
>> + if (ret & BRA_HSTS_ERR_MASK) {
>> + pr_debug("%s: HSTS(0x%02X): 0x%X\n", __func__, cmd, ret);
>> + status = -EIO;
>> + goto err;
>> + }
>> +
>> + if (operation == SMBUS_READ) {
>> + *result = ((inb(HDAT0) & 0xff) + ((inb(HDAT1) & 0xff) << 8));
>> + pr_debug("%s: READ (0x%02x - count %05d): 0x%04x\n",
>> + __func__, cmd, count, *result);
>> + }
>> +
>> +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");
>> +
>
> Empty line
>
>> + } 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);
>> + return status;
>> +}
>> +
>> +static int secocec_adap_log_addr(struct cec_adapter *adap, u8 logical_addr)
>> +{
>> + u16 enable_val = 0;
>> + int status;
>> +
>> + /* 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);
>> + 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 / 2 + payload_len % 2; i++) {
>> + /* hi byte */
>> + val = payload_msg[(i << 1) + 1] << 8;
>> +
>> + /* lo byte */
>> + val |= payload_msg[(i << 1)];
>> +
>> + status = smb_wr16(SECOCEC_WRITE_DATA_00 + i, 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);
>> + return status;
>> +}
>> +
>> +static int secocec_tx_done(struct cec_adapter *adap, u16 status_val)
>> +{
>> + 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)
>> +{
>> + 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");
>> + 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;
>> +
>> + dev_dbg(dev, "Incoming message (payload len %d):", val);
>> +
>> + /* 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 if present */
>> + if (msg.len > 0) {
>
> Am I wrong or msg.len is at least (val + 1) and val is never negative?
> If that's true, this condition is always verified.
>
>> + 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 / 2 + payload_len % 2; i++) {
>> + status = smb_rd16(SECOCEC_READ_DATA_00 + i, &val);
>> + if (status)
>> + goto err;
>> +
>> + /* low byte, skipping header */
>> + payload_msg[(i << 1)] = val & 0x00ff;
>> +
>> + /* hi byte */
>> + payload_msg[(i << 1) + 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;
>> +
>> + dev_dbg(dev, "Message received successfully");
>> +
>> + 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) {
>> + dev_dbg(dev, "+++++ CEC Interrupt Caught");
>
> Just be carefull in too much printouts while handling interrupts.
> Also, I would not insert custom printout formats (here and below in
> this functions). I would simply drop this one.
>
>> +
>> + /* 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 \\_\"._/");
>
> No custom funny printouts please :)
>
>> +
>> + val = SECOCEC_STATUS_REG_1_CEC;
>> + }
>> +
>> + if (status_val & SECOCEC_STATUS_REG_1_IR) {
>> + dev_dbg(dev, "IR RC5 Interrupt Caught");
>
> How frequent is this one? Do you need to print it out?
>
>> + val |= SECOCEC_STATUS_REG_1_IR;
>> + /* TODO IRDA RX */
>> + }
>> +
>> + /* Reset status register */
>> + status = smb_wr16(SECOCEC_STATUS_REG_1, val);
>> + if (status)
>> + goto err;
>> +
>> + dev_dbg(dev, "----- CEC Interrupt Handled");
>
> Drop this one please
>
>> +
>> + return IRQ_HANDLED;
>> +
>> +err:
>> + dev_err(dev, "IRQ: Read/Write SMBus operation failed (%d)", status);
>> +
>> + /* 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)

If you compare this driver with cros-ec-cec.c, then you'll see that
there this function is under "#if IS_ENABLED(CONFIG_PCI) && IS_ENABLED(CONFIG_DMI)".

I think you should do the same and (just like cros-ec-cec.c) add a dummy function
in the #else part.

>> +{
>> + 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);
>
> Nit: it's usually nice to have an empty line before return (here and in
> other places). Not mandatory though.
>
>> + 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;
>> + u8 cec_caps;
>> + 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;
>> + }
>> +
>> +#ifdef CONFIG_CEC_NOTIFIER
>
> Your Kconfig entry selects CEC_NOTIFIER.

Yes, this #ifdef line can be dropped.

>
> (I won't comment on the cec_notifier handling part, as I don't know
> much. I just see other drivers registering and getting the notifier
> using the cec_notifier_ functions, while it seems to me you don't.
> Maybe it's fine...)

It's fine :-)

>
>> + ret = secocec_cec_get_notifier(&secocec->notifier);
>> + if (ret) {
>> + dev_err(dev, "no CEC notifier available\n");
>> + goto err;
>> + }
>> +#endif
>> +
>> + 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 */
>> + cec_caps = CEC_CAP_DEFAULTS;
>> +
>> + secocec->cec_adap = cec_allocate_adapter(&secocec_cec_adap_ops,
>> + secocec,
>> + dev_name(dev),
>> + cec_caps, SECOCEC_MAX_ADDRS);

You can drop cec_caps and just pass CEC_CAP_DEFAULTS directly.

>> +
>> + 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
>
> I see CONFIG_PM_SLEEP is only selected if support for
> 'suspend'/'hibernate' is enabled. Is this what you want, or you should
> check for CONFIG_PM?
>
>> +static int secocec_suspend(struct device *dev)
>> +{
>> + u16 val;
>> + int status;
>> +
>> + 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)
>> +{
>> + u16 val;
>> + int status;
>> +
>> + 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,
>> +};
>
> As you can see most of my comments are nits or trivial things. I would
> wait for more feedbacks on the CEC and x86/SMbus part from others before
> sending v2 if I were you :)
>
> Thanks
> j
>
>
>> +
>> +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..cc7f0cba8e9e
>> --- /dev/null
>> +++ b/drivers/media/platform/seco-cec/seco-cec.h
>> @@ -0,0 +1,132 @@
>> +/* SPDX-License-Identifier: GPL-2.0 AND 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__ */
>> --
>> 2.18.0
>>

Regards,

Hans