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 whant the Embedded Controller supports. Signed-off-by: Gwendal Grignou <[email protected]> --- drivers/mfd/cros_ec_dev.c | 61 ++++++++++++++++++++++++++++++++++++- include/linux/mfd/cros_ec.h | 17 +++++++++++ 2 files changed, 77 insertions(+), 1 deletion(-) diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c index 6e6dfd6c1871..3be80183ccaa 100644 --- a/drivers/mfd/cros_ec_dev.c +++ b/drivers/mfd/cros_ec_dev.c @@ -112,7 +112,7 @@ 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) +int cros_ec_check_features(struct cros_ec_dev *ec, int feature) { struct cros_ec_command *msg; int ret; @@ -143,12 +143,71 @@ static int cros_ec_check_features(struct cros_ec_dev *ec, int feature) return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature); } +EXPORT_SYMBOL_GPL(cros_ec_check_features); static void cros_ec_class_release(struct device *dev) { kfree(to_cros_ec_dev(dev)); } +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(struct cros_ec_command) + + max(sizeof(*params), sizeof(*resp)), GFP_KERNEL); + if (msg == NULL) + 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; + } + } + return sensor_count; +} +EXPORT_SYMBOL_GPL(cros_ec_get_sensor_count); + static void cros_ec_sensors_register(struct cros_ec_dev *ec) { /* diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h index 61c2875c2a40..578e0bbcafdc 100644 --- a/include/linux/mfd/cros_ec.h +++ b/include/linux/mfd/cros_ec.h @@ -32,4 +32,21 @@ struct cros_ec_dev { #define to_cros_ec_dev(dev) container_of(dev, struct cros_ec_dev, class_dev) +/** + * cros_ec_check_features - Test for the presence of EC features + * + * Call this function to test whether the ChromeOS EC supports a feature. + * + * @ec_dev: EC device + * @msg: One of ec_feature_code values + * @return: 1 if supported, 0 if not + */ +int cros_ec_check_features(struct cros_ec_dev *ec, int feature); + +/* + * Return the number of MEMS sensors supported. + * Return < 0 in case of error. + */ +int cros_ec_get_sensor_count(struct cros_ec_dev *ec); + #endif /* __LINUX_MFD_CROS_EC_H */ -- 2.23.0.351.gc4317032e6-goog
