Re: [PATCH v4 01/17] mfd: cros_ec: Add sensor_count and make check_features public

Enric Balletbo Serra
2019-11-08T22:04:11Z

Missatge de Gwendal Grignou <gwendal@chromium.org> del dia dt., 5 de
nov. 2019 a les 23:28:
>
> Add a new function to return the number of MEMS sensors available in a
> ChromeOS Embedded Controller.
> It uses MOTIONSENSE_CMD_DUMP if available or a specific memory map ACPI
> registers to find out.
>
> Also, make check_features public as it can be useful for other drivers
> to know what the Embedded Controller supports.
>
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>

Version 3 was acked and I think we can maintain his ack, so:

Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>

Also,

Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

Lee, how you would like to handle this? I think will be safe for
patches 1/2/3 go through the platform-chrome tree without an immutable
branch. Patch 3 thought still needs and Ack from you if is fine.

Thanks,
Enric

> ---
> Changes in v4:
> Check patch with --strict option
> Use sizeof(*obj) instead of sizeof(struct ...obj)
> Alignement
> Remove useless ().
> Changes in v3:
> Fix doxygen comments.
> Changes in v2:
> Fix spelling in commit message.
> Cleanup the case where DUMP command is not supported.
> Move code from mfd to platform/chrome/
>
> drivers/mfd/cros_ec_dev.c | 32 ------
> drivers/platform/chrome/cros_ec_proto.c | 117 ++++++++++++++++++++
> include/linux/platform_data/cros_ec_proto.h | 5 +
> 3 files changed, 122 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
> index 6e6dfd6c1871..a35104e35cb4 100644
> --- a/drivers/mfd/cros_ec_dev.c
> +++ b/drivers/mfd/cros_ec_dev.c
> @@ -112,38 +112,6 @@ static const struct mfd_cell cros_ec_vbc_cells[] = {
> { .name = "cros-ec-vbc", }
> };
>
> -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 = kzalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL);
> - if (!msg)
> - return -ENOMEM;
> -
> - msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset;
> - msg->insize = sizeof(ec->features);
> -
> - ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
> - if (ret < 0) {
> - dev_warn(ec->dev, "cannot get EC features: %d/%d\n",
> - ret, msg->result);
> - memset(ec->features, 0, sizeof(ec->features));
> - } else {
> - 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);
> -}
> -
> static void cros_ec_class_release(struct device *dev)
> {
> kfree(to_cros_ec_dev(dev));
> diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
> index 7db58771ec77..b502933e911b 100644
> --- a/drivers/platform/chrome/cros_ec_proto.c
> +++ b/drivers/platform/chrome/cros_ec_proto.c
> @@ -717,3 +717,120 @@ u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev)
> return host_event;
> }
> EXPORT_SYMBOL(cros_ec_get_host_event);
> +
> +/**
> + * cros_ec_check_features - Test for the presence of EC features
> + *
> + * @ec: EC device, does not have to be connected directly to the AP,
> + * can be daisy chained through another device.
> + * @feature: One of ec_feature_code bit.
> + *
> + * Call this function to test whether the ChromeOS EC supports a feature.
> + *
> + * Return: 1 if supported, 0 if not
> + */
> +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 = kzalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL);
> + if (!msg)
> + return -ENOMEM;
> +
> + msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset;
> + msg->insize = sizeof(ec->features);
> +
> + ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
> + if (ret < 0) {
> + dev_warn(ec->dev, "cannot get EC features: %d/%d\n",
> + ret, msg->result);
> + memset(ec->features, 0, sizeof(ec->features));
> + } else {
> + 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);
> +}
> +EXPORT_SYMBOL_GPL(cros_ec_check_features);
> +
> +/**
> + * cros_ec_get_sensor_count - Return the number of MEMS sensors supported.
> + *
> + * @ec: EC device, does not have to be connected directly to the AP,
> + * can be daisy chained through another device.
> + * Return: < 0 in case of error.
> + */
> +int cros_ec_get_sensor_count(struct cros_ec_dev *ec)
> +{
> + /*
> + * Issue a command to get the number of sensor reported.
> + * If not supported, check for legacy mode.
> + */
> + int ret, sensor_count;
> + struct ec_params_motion_sense *params;
> + struct ec_response_motion_sense *resp;
> + struct cros_ec_command *msg;
> + struct cros_ec_device *ec_dev = ec->ec_dev;
> + u8 status;
> +
> + msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)),
> + GFP_KERNEL);
> + if (!msg)
> + return -ENOMEM;
> +
> + msg->version = 1;
> + msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
> + msg->outsize = sizeof(*params);
> + msg->insize = sizeof(*resp);
> +
> + params = (struct ec_params_motion_sense *)msg->data;
> + params->cmd = MOTIONSENSE_CMD_DUMP;
> +
> + ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
> + if (ret < 0) {
> + sensor_count = ret;
> + } else if (msg->result != EC_RES_SUCCESS) {
> + sensor_count = -EPROTO;
> + } else {
> + resp = (struct ec_response_motion_sense *)msg->data;
> + sensor_count = resp->dump.sensor_count;
> + }
> + kfree(msg);
> +
> + /*
> + * Check legacy mode: Let's find out if sensors are accessible
> + * via LPC interface.
> + */
> + if (sensor_count == -EPROTO &&
> + ec->cmd_offset == 0 &&
> + ec_dev->cmd_readmem) {
> + ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS,
> + 1, &status);
> + if (ret >= 0 &&
> + (status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
> + /*
> + * We have 2 sensors, one in the lid, one in the base.
> + */
> + sensor_count = 2;
> + } else {
> + /*
> + * EC uses LPC interface and no sensors are presented.
> + */
> + sensor_count = 0;
> + }
> + } else if (sensor_count == -EPROTO) {
> + /* EC responded, but does not understand DUMP command. */
> + sensor_count = 0;
> + }
> + return sensor_count;
> +}
> +EXPORT_SYMBOL_GPL(cros_ec_get_sensor_count);
> diff --git a/include/linux/platform_data/cros_ec_proto.h b/include/linux/platform_data/cros_ec_proto.h
> index 0d4e4aaed37a..f3de0662135d 100644
> --- a/include/linux/platform_data/cros_ec_proto.h
> +++ b/include/linux/platform_data/cros_ec_proto.h
> @@ -12,6 +12,7 @@
> #include <linux/mutex.h>
> #include <linux/notifier.h>
>
> +#include <linux/mfd/cros_ec.h>
> #include <linux/platform_data/cros_ec_commands.h>
>
> #define CROS_EC_DEV_NAME "cros_ec"
> @@ -213,4 +214,8 @@ int cros_ec_get_next_event(struct cros_ec_device *ec_dev, bool *wake_event);
>
> u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);
>
> +int cros_ec_check_features(struct cros_ec_dev *ec, int feature);
> +
> +int cros_ec_get_sensor_count(struct cros_ec_dev *ec);
> +
> #endif /* __LINUX_CROS_EC_PROTO_H */
> --
> 2.24.0.rc1.363.gb1bccd3e3d-goog
>