From a16b2e28190255a0729c27902fa88fb8fff39bb0 Mon Sep 17 00:00:00 2001 From: Gwendal Grignou Date: Tue, 19 Nov 2019 13:45:45 +0100 Subject: [PATCH] mfd / platform: cros_ec: Add sensor_count and make check_features public 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 Acked-by: Lee Jones Signed-off-by: Enric Balletbo i Serra --- 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..12bdd1f3aee9 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 #include +#include #include #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 */