Re: [PATCH v4 3/4] platform/chrome: Introduce a new function to check EC features.

Lee Jones
2016-08-09T13:58:22Z

On Mon, 01 Aug 2016, Enric Balletbo i Serra wrote:

> From: Vincent Palatin <vpalatin@chromium.org>
>
> Use the EC_CMD_GET_FEATURES message to check the supported features for
> each MCU.
>
> Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
> [tomeu: adapted to changes in mainline]
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> [enric: remove references to USB PD feature and do it more generic]
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> Reviewed-by: Guenter Roeck <groeck@chromium.org>
> ---
>
> Changes since v3:
> - Add Reviewed-by tag.
>
> drivers/platform/chrome/cros_ec_dev.c | 37 +++++++++++++++
> include/linux/mfd/cros_ec.h | 1 +
> include/linux/mfd/cros_ec_commands.h | 84 +++++++++++++++++++++++++++++++++++

For the MFD changes:
Acked-by: Lee Jones <lee.jones@linaro.org>

> 3 files changed, 122 insertions(+)
>
> diff --git a/drivers/platform/chrome/cros_ec_dev.c b/drivers/platform/chrome/cros_ec_dev.c
> index 8abd80d..7eb5307 100644
> --- a/drivers/platform/chrome/cros_ec_dev.c
> +++ b/drivers/platform/chrome/cros_ec_dev.c
> @@ -87,6 +87,41 @@ exit:
> return ret;
> }
>
> +static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
> +{
> + struct cros_ec_command *msg;
> + int ret;
> +
> + if (ec->features[0] == -1U && ec->features[1] == -1U) {
> + /* features bitmap not read yet */
> +
> + msg = kmalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL);
> + if (!msg)
> + return -ENOMEM;
> +
> + msg->version = 0;
> + msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset;
> + msg->insize = sizeof(ec->features);
> + msg->outsize = 0;
> +
> + ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
> + if (ret < 0 || msg->result != EC_RES_SUCCESS) {
> + dev_warn(ec->dev, "cannot get EC features: %d/%d\n",
> + ret, msg->result);
> + memset(ec->features, 0, sizeof(ec->features));
> + }
> +
> + memcpy(ec->features, msg->data, sizeof(ec->features));
> +
> + dev_dbg(ec->dev, "EC features %08x %08x\n",
> + ec->features[0], ec->features[1]);
> +
> + kfree(msg);
> + }
> +
> + return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature);
> +}
> +
> /* Device file ops */
> static int ec_device_open(struct inode *inode, struct file *filp)
> {
> @@ -245,6 +280,8 @@ static int ec_device_probe(struct platform_device *pdev)
> ec->ec_dev = dev_get_drvdata(dev->parent);
> ec->dev = dev;
> ec->cmd_offset = ec_platform->cmd_offset;
> + ec->features[0] = -1U; /* Not cached yet */
> + ec->features[1] = -1U; /* Not cached yet */
> device_initialize(&ec->class_dev);
> cdev_init(&ec->cdev, &fops);
>
> diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
> index 7769ea6..7f039b2 100644
> --- a/include/linux/mfd/cros_ec.h
> +++ b/include/linux/mfd/cros_ec.h
> @@ -187,6 +187,7 @@ struct cros_ec_dev {
> struct cros_ec_device *ec_dev;
> struct device *dev;
> u16 cmd_offset;
> + u32 features[2];
> };
>
> /**
> diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h
> index 8826e0f..1683003 100644
> --- a/include/linux/mfd/cros_ec_commands.h
> +++ b/include/linux/mfd/cros_ec_commands.h
> @@ -713,6 +713,90 @@ struct ec_response_get_set_value {
> /* More than one command can use these structs to get/set paramters. */
> #define EC_CMD_GSV_PAUSE_IN_S5 0x0c
>
> +/*****************************************************************************/
> +/* List the features supported by the firmware */
> +#define EC_CMD_GET_FEATURES 0x0d
> +
> +/* Supported features */
> +enum ec_feature_code {
> + /*
> + * This image contains a limited set of features. Another image
> + * in RW partition may support more features.
> + */
> + EC_FEATURE_LIMITED = 0,
> + /*
> + * Commands for probing/reading/writing/erasing the flash in the
> + * EC are present.
> + */
> + EC_FEATURE_FLASH = 1,
> + /*
> + * Can control the fan speed directly.
> + */
> + EC_FEATURE_PWM_FAN = 2,
> + /*
> + * Can control the intensity of the keyboard backlight.
> + */
> + EC_FEATURE_PWM_KEYB = 3,
> + /*
> + * Support Google lightbar, introduced on Pixel.
> + */
> + EC_FEATURE_LIGHTBAR = 4,
> + /* Control of LEDs */
> + EC_FEATURE_LED = 5,
> + /* Exposes an interface to control gyro and sensors.
> + * The host goes through the EC to access these sensors.
> + * In addition, the EC may provide composite sensors, like lid angle.
> + */
> + EC_FEATURE_MOTION_SENSE = 6,
> + /* The keyboard is controlled by the EC */
> + EC_FEATURE_KEYB = 7,
> + /* The AP can use part of the EC flash as persistent storage. */
> + EC_FEATURE_PSTORE = 8,
> + /* The EC monitors BIOS port 80h, and can return POST codes. */
> + EC_FEATURE_PORT80 = 9,
> + /*
> + * Thermal management: include TMP specific commands.
> + * Higher level than direct fan control.
> + */
> + EC_FEATURE_THERMAL = 10,
> + /* Can switch the screen backlight on/off */
> + EC_FEATURE_BKLIGHT_SWITCH = 11,
> + /* Can switch the wifi module on/off */
> + EC_FEATURE_WIFI_SWITCH = 12,
> + /* Monitor host events, through for example SMI or SCI */
> + EC_FEATURE_HOST_EVENTS = 13,
> + /* The EC exposes GPIO commands to control/monitor connected devices. */
> + EC_FEATURE_GPIO = 14,
> + /* The EC can send i2c messages to downstream devices. */
> + EC_FEATURE_I2C = 15,
> + /* Command to control charger are included */
> + EC_FEATURE_CHARGER = 16,
> + /* Simple battery support. */
> + EC_FEATURE_BATTERY = 17,
> + /*
> + * Support Smart battery protocol
> + * (Common Smart Battery System Interface Specification)
> + */
> + EC_FEATURE_SMART_BATTERY = 18,
> + /* EC can dectect when the host hangs. */
> + EC_FEATURE_HANG_DETECT = 19,
> + /* Report power information, for pit only */
> + EC_FEATURE_PMU = 20,
> + /* Another Cros EC device is present downstream of this one */
> + EC_FEATURE_SUB_MCU = 21,
> + /* Support USB Power delivery (PD) commands */
> + EC_FEATURE_USB_PD = 22,
> + /* Control USB multiplexer, for audio through USB port for instance. */
> + EC_FEATURE_USB_MUX = 23,
> + /* Motion Sensor code has an internal software FIFO */
> + EC_FEATURE_MOTION_SENSE_FIFO = 24,
> +};
> +
> +#define EC_FEATURE_MASK_0(event_code) (1UL << (event_code % 32))
> +#define EC_FEATURE_MASK_1(event_code) (1UL << (event_code - 32))
> +struct ec_response_get_features {
> + uint32_t flags[2];
> +} __packed;
>
> /*****************************************************************************/
> /* Flash commands */

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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