diff options
Diffstat (limited to 'drivers/staging/greybus/fw-management.c')
| -rw-r--r-- | drivers/staging/greybus/fw-management.c | 721 |
1 files changed, 721 insertions, 0 deletions
diff --git a/drivers/staging/greybus/fw-management.c b/drivers/staging/greybus/fw-management.c new file mode 100644 index 000000000000..3cd6cf0a656b --- /dev/null +++ b/drivers/staging/greybus/fw-management.c @@ -0,0 +1,721 @@ +/* + * Greybus Firmware Management Protocol Driver. + * + * Copyright 2016 Google Inc. + * Copyright 2016 Linaro Ltd. + * + * Released under the GPLv2 only. + */ + +#include <linux/cdev.h> +#include <linux/completion.h> +#include <linux/firmware.h> +#include <linux/fs.h> +#include <linux/idr.h> +#include <linux/ioctl.h> +#include <linux/uaccess.h> + +#include "firmware.h" +#include "greybus_firmware.h" +#include "greybus.h" + +#define FW_MGMT_TIMEOUT_MS 1000 + +struct fw_mgmt { + struct device *parent; + struct gb_connection *connection; + struct kref kref; + struct list_head node; + + /* Common id-map for interface and backend firmware requests */ + struct ida id_map; + struct mutex mutex; + struct completion completion; + struct cdev cdev; + struct device *class_device; + dev_t dev_num; + unsigned int timeout_jiffies; + bool disabled; /* connection getting disabled */ + + /* Interface Firmware specific fields */ + bool mode_switch_started; + bool intf_fw_loaded; + u8 intf_fw_request_id; + u8 intf_fw_status; + u16 intf_fw_major; + u16 intf_fw_minor; + + /* Backend Firmware specific fields */ + u8 backend_fw_request_id; + u8 backend_fw_status; +}; + +/* + * Number of minor devices this driver supports. + * There will be exactly one required per Interface. + */ +#define NUM_MINORS U8_MAX + +static struct class *fw_mgmt_class; +static dev_t fw_mgmt_dev_num; +static DEFINE_IDA(fw_mgmt_minors_map); +static LIST_HEAD(fw_mgmt_list); +static DEFINE_MUTEX(list_mutex); + +static void fw_mgmt_kref_release(struct kref *kref) +{ + struct fw_mgmt *fw_mgmt = container_of(kref, struct fw_mgmt, kref); + + ida_destroy(&fw_mgmt->id_map); + kfree(fw_mgmt); +} + +/* + * All users of fw_mgmt take a reference (from within list_mutex lock), before + * they get a pointer to play with. And the structure will be freed only after + * the last user has put the reference to it. + */ +static void put_fw_mgmt(struct fw_mgmt *fw_mgmt) +{ + kref_put(&fw_mgmt->kref, fw_mgmt_kref_release); +} + +/* Caller must call put_fw_mgmt() after using struct fw_mgmt */ +static struct fw_mgmt *get_fw_mgmt(struct cdev *cdev) +{ + struct fw_mgmt *fw_mgmt; + + mutex_lock(&list_mutex); + + list_for_each_entry(fw_mgmt, &fw_mgmt_list, node) { + if (&fw_mgmt->cdev == cdev) { + kref_get(&fw_mgmt->kref); + goto unlock; + } + } + + fw_mgmt = NULL; + +unlock: + mutex_unlock(&list_mutex); + + return fw_mgmt; +} + +static int fw_mgmt_interface_fw_version_operation(struct fw_mgmt *fw_mgmt, + struct fw_mgmt_ioc_get_intf_version *fw_info) +{ + struct gb_connection *connection = fw_mgmt->connection; + struct gb_fw_mgmt_interface_fw_version_response response; + int ret; + + ret = gb_operation_sync(connection, + GB_FW_MGMT_TYPE_INTERFACE_FW_VERSION, NULL, 0, + &response, sizeof(response)); + if (ret) { + dev_err(fw_mgmt->parent, + "failed to get interface firmware version (%d)\n", ret); + return ret; + } + + fw_info->major = le16_to_cpu(response.major); + fw_info->minor = le16_to_cpu(response.minor); + + strncpy(fw_info->firmware_tag, response.firmware_tag, + GB_FIRMWARE_TAG_MAX_SIZE); + + /* + * The firmware-tag should be NULL terminated, otherwise throw error but + * don't fail. + */ + if (fw_info->firmware_tag[GB_FIRMWARE_TAG_MAX_SIZE - 1] != '\0') { + dev_err(fw_mgmt->parent, + "fw-version: firmware-tag is not NULL terminated\n"); + fw_info->firmware_tag[GB_FIRMWARE_TAG_MAX_SIZE - 1] = '\0'; + } + + return 0; +} + +static int fw_mgmt_load_and_validate_operation(struct fw_mgmt *fw_mgmt, + u8 load_method, const char *tag) +{ + struct gb_fw_mgmt_load_and_validate_fw_request request; + int ret; + + if (load_method != GB_FW_LOAD_METHOD_UNIPRO && + load_method != GB_FW_LOAD_METHOD_INTERNAL) { + dev_err(fw_mgmt->parent, + "invalid load-method (%d)\n", load_method); + return -EINVAL; + } + + request.load_method = load_method; + strncpy(request.firmware_tag, tag, GB_FIRMWARE_TAG_MAX_SIZE); + + /* + * The firmware-tag should be NULL terminated, otherwise throw error and + * fail. + */ + if (request.firmware_tag[GB_FIRMWARE_TAG_MAX_SIZE - 1] != '\0') { + dev_err(fw_mgmt->parent, "load-and-validate: firmware-tag is not NULL terminated\n"); + return -EINVAL; + } + + /* Allocate ids from 1 to 255 (u8-max), 0 is an invalid id */ + ret = ida_simple_get(&fw_mgmt->id_map, 1, 256, GFP_KERNEL); + if (ret < 0) { + dev_err(fw_mgmt->parent, "failed to allocate request id (%d)\n", + ret); + return ret; + } + + fw_mgmt->intf_fw_request_id = ret; + fw_mgmt->intf_fw_loaded = false; + request.request_id = ret; + + ret = gb_operation_sync(fw_mgmt->connection, + GB_FW_MGMT_TYPE_LOAD_AND_VALIDATE_FW, &request, + sizeof(request), NULL, 0); + if (ret) { + ida_simple_remove(&fw_mgmt->id_map, + fw_mgmt->intf_fw_request_id); + fw_mgmt->intf_fw_request_id = 0; + dev_err(fw_mgmt->parent, + "load and validate firmware request failed (%d)\n", + ret); + return ret; + } + + return 0; +} + +static int fw_mgmt_interface_fw_loaded_operation(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct fw_mgmt *fw_mgmt = gb_connection_get_data(connection); + struct gb_fw_mgmt_loaded_fw_request *request; + + /* No pending load and validate request ? */ + if (!fw_mgmt->intf_fw_request_id) { + dev_err(fw_mgmt->parent, + "unexpected firmware loaded request received\n"); + return -ENODEV; + } + + if (op->request->payload_size != sizeof(*request)) { + dev_err(fw_mgmt->parent, "illegal size of firmware loaded request (%zu != %zu)\n", + op->request->payload_size, sizeof(*request)); + return -EINVAL; + } + + request = op->request->payload; + + /* Invalid request-id ? */ + if (request->request_id != fw_mgmt->intf_fw_request_id) { + dev_err(fw_mgmt->parent, "invalid request id for firmware loaded request (%02u != %02u)\n", + fw_mgmt->intf_fw_request_id, request->request_id); + return -ENODEV; + } + + ida_simple_remove(&fw_mgmt->id_map, fw_mgmt->intf_fw_request_id); + fw_mgmt->intf_fw_request_id = 0; + fw_mgmt->intf_fw_status = request->status; + fw_mgmt->intf_fw_major = le16_to_cpu(request->major); + fw_mgmt->intf_fw_minor = le16_to_cpu(request->minor); + + if (fw_mgmt->intf_fw_status == GB_FW_LOAD_STATUS_FAILED) + dev_err(fw_mgmt->parent, + "failed to load interface firmware, status:%02x\n", + fw_mgmt->intf_fw_status); + else if (fw_mgmt->intf_fw_status == GB_FW_LOAD_STATUS_VALIDATION_FAILED) + dev_err(fw_mgmt->parent, + "failed to validate interface firmware, status:%02x\n", + fw_mgmt->intf_fw_status); + else + fw_mgmt->intf_fw_loaded = true; + + complete(&fw_mgmt->completion); + + return 0; +} + +static int fw_mgmt_backend_fw_version_operation(struct fw_mgmt *fw_mgmt, + struct fw_mgmt_ioc_get_backend_version *fw_info) +{ + struct gb_connection *connection = fw_mgmt->connection; + struct gb_fw_mgmt_backend_fw_version_request request; + struct gb_fw_mgmt_backend_fw_version_response response; + int ret; + + strncpy(request.firmware_tag, fw_info->firmware_tag, + GB_FIRMWARE_TAG_MAX_SIZE); + + /* + * The firmware-tag should be NULL terminated, otherwise throw error and + * fail. + */ + if (request.firmware_tag[GB_FIRMWARE_TAG_MAX_SIZE - 1] != '\0') { + dev_err(fw_mgmt->parent, "backend-version: firmware-tag is not NULL terminated\n"); + return -EINVAL; + } + + ret = gb_operation_sync(connection, + GB_FW_MGMT_TYPE_BACKEND_FW_VERSION, &request, + sizeof(request), &response, sizeof(response)); + if (ret) { + dev_err(fw_mgmt->parent, "failed to get version of %s backend firmware (%d)\n", + fw_info->firmware_tag, ret); + return ret; + } + + fw_info->status = response.status; + + /* Reset version as that should be non-zero only for success case */ + fw_info->major = 0; + fw_info->minor = 0; + + switch (fw_info->status) { + case GB_FW_BACKEND_VERSION_STATUS_SUCCESS: + fw_info->major = le16_to_cpu(response.major); + fw_info->minor = le16_to_cpu(response.minor); + break; + case GB_FW_BACKEND_VERSION_STATUS_NOT_AVAILABLE: + case GB_FW_BACKEND_VERSION_STATUS_RETRY: + break; + case GB_FW_BACKEND_VERSION_STATUS_NOT_SUPPORTED: + dev_err(fw_mgmt->parent, + "Firmware with tag %s is not supported by Interface\n", + fw_info->firmware_tag); + break; + default: + dev_err(fw_mgmt->parent, "Invalid status received: %u\n", + fw_info->status); + } + + return 0; +} + +static int fw_mgmt_backend_fw_update_operation(struct fw_mgmt *fw_mgmt, + char *tag) +{ + struct gb_fw_mgmt_backend_fw_update_request request; + int ret; + + strncpy(request.firmware_tag, tag, GB_FIRMWARE_TAG_MAX_SIZE); + + /* + * The firmware-tag should be NULL terminated, otherwise throw error and + * fail. + */ + if (request.firmware_tag[GB_FIRMWARE_TAG_MAX_SIZE - 1] != '\0') { + dev_err(fw_mgmt->parent, "backend-update: firmware-tag is not NULL terminated\n"); + return -EINVAL; + } + + /* Allocate ids from 1 to 255 (u8-max), 0 is an invalid id */ + ret = ida_simple_get(&fw_mgmt->id_map, 1, 256, GFP_KERNEL); + if (ret < 0) { + dev_err(fw_mgmt->parent, "failed to allocate request id (%d)\n", + ret); + return ret; + } + + fw_mgmt->backend_fw_request_id = ret; + request.request_id = ret; + + ret = gb_operation_sync(fw_mgmt->connection, + GB_FW_MGMT_TYPE_BACKEND_FW_UPDATE, &request, + sizeof(request), NULL, 0); + if (ret) { + ida_simple_remove(&fw_mgmt->id_map, + fw_mgmt->backend_fw_request_id); + fw_mgmt->backend_fw_request_id = 0; + dev_err(fw_mgmt->parent, + "backend %s firmware update request failed (%d)\n", tag, + ret); + return ret; + } + + return 0; +} + +static int fw_mgmt_backend_fw_updated_operation(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct fw_mgmt *fw_mgmt = gb_connection_get_data(connection); + struct gb_fw_mgmt_backend_fw_updated_request *request; + + /* No pending load and validate request ? */ + if (!fw_mgmt->backend_fw_request_id) { + dev_err(fw_mgmt->parent, "unexpected backend firmware updated request received\n"); + return -ENODEV; + } + + if (op->request->payload_size != sizeof(*request)) { + dev_err(fw_mgmt->parent, "illegal size of backend firmware updated request (%zu != %zu)\n", + op->request->payload_size, sizeof(*request)); + return -EINVAL; + } + + request = op->request->payload; + + /* Invalid request-id ? */ + if (request->request_id != fw_mgmt->backend_fw_request_id) { + dev_err(fw_mgmt->parent, "invalid request id for backend firmware updated request (%02u != %02u)\n", + fw_mgmt->backend_fw_request_id, request->request_id); + return -ENODEV; + } + + ida_simple_remove(&fw_mgmt->id_map, fw_mgmt->backend_fw_request_id); + fw_mgmt->backend_fw_request_id = 0; + fw_mgmt->backend_fw_status = request->status; + + if ((fw_mgmt->backend_fw_status != GB_FW_BACKEND_FW_STATUS_SUCCESS) && + (fw_mgmt->backend_fw_status != GB_FW_BACKEND_FW_STATUS_RETRY)) + dev_err(fw_mgmt->parent, + "failed to load backend firmware: %02x\n", + fw_mgmt->backend_fw_status); + + complete(&fw_mgmt->completion); + + return 0; +} + +/* Char device fops */ + +static int fw_mgmt_open(struct inode *inode, struct file *file) +{ + struct fw_mgmt *fw_mgmt = get_fw_mgmt(inode->i_cdev); + + /* fw_mgmt structure can't get freed until file descriptor is closed */ + if (fw_mgmt) { + file->private_data = fw_mgmt; + return 0; + } + + return -ENODEV; +} + +static int fw_mgmt_release(struct inode *inode, struct file *file) +{ + struct fw_mgmt *fw_mgmt = file->private_data; + + put_fw_mgmt(fw_mgmt); + return 0; +} + +static int fw_mgmt_ioctl(struct fw_mgmt *fw_mgmt, unsigned int cmd, + void __user *buf) +{ + struct fw_mgmt_ioc_get_intf_version intf_fw_info; + struct fw_mgmt_ioc_get_backend_version backend_fw_info; + struct fw_mgmt_ioc_intf_load_and_validate intf_load; + struct fw_mgmt_ioc_backend_fw_update backend_update; + unsigned int timeout; + int ret; + + /* Reject any operations after mode-switch has started */ + if (fw_mgmt->mode_switch_started) + return -EBUSY; + + switch (cmd) { + case FW_MGMT_IOC_GET_INTF_FW: + ret = fw_mgmt_interface_fw_version_operation(fw_mgmt, + &intf_fw_info); + if (ret) + return ret; + + if (copy_to_user(buf, &intf_fw_info, sizeof(intf_fw_info))) + return -EFAULT; + + return 0; + case FW_MGMT_IOC_GET_BACKEND_FW: + if (copy_from_user(&backend_fw_info, buf, + sizeof(backend_fw_info))) + return -EFAULT; + + ret = fw_mgmt_backend_fw_version_operation(fw_mgmt, + &backend_fw_info); + if (ret) + return ret; + + if (copy_to_user(buf, &backend_fw_info, + sizeof(backend_fw_info))) + return -EFAULT; + + return 0; + case FW_MGMT_IOC_INTF_LOAD_AND_VALIDATE: + if (copy_from_user(&intf_load, buf, sizeof(intf_load))) + return -EFAULT; + + ret = fw_mgmt_load_and_validate_operation(fw_mgmt, + intf_load.load_method, intf_load.firmware_tag); + if (ret) + return ret; + + if (!wait_for_completion_timeout(&fw_mgmt->completion, + fw_mgmt->timeout_jiffies)) { + dev_err(fw_mgmt->parent, "timed out waiting for firmware load and validation to finish\n"); + return -ETIMEDOUT; + } + + intf_load.status = fw_mgmt->intf_fw_status; + intf_load.major = fw_mgmt->intf_fw_major; + intf_load.minor = fw_mgmt->intf_fw_minor; + + if (copy_to_user(buf, &intf_load, sizeof(intf_load))) + return -EFAULT; + + return 0; + case FW_MGMT_IOC_INTF_BACKEND_FW_UPDATE: + if (copy_from_user(&backend_update, buf, + sizeof(backend_update))) + return -EFAULT; + + ret = fw_mgmt_backend_fw_update_operation(fw_mgmt, + backend_update.firmware_tag); + if (ret) + return ret; + + if (!wait_for_completion_timeout(&fw_mgmt->completion, + fw_mgmt->timeout_jiffies)) { + dev_err(fw_mgmt->parent, "timed out waiting for backend firmware update to finish\n"); + return -ETIMEDOUT; + } + + backend_update.status = fw_mgmt->backend_fw_status; + + if (copy_to_user(buf, &backend_update, sizeof(backend_update))) + return -EFAULT; + + return 0; + case FW_MGMT_IOC_SET_TIMEOUT_MS: + if (get_user(timeout, (unsigned int __user *)buf)) + return -EFAULT; + + if (!timeout) { + dev_err(fw_mgmt->parent, "timeout can't be zero\n"); + return -EINVAL; + } + + fw_mgmt->timeout_jiffies = msecs_to_jiffies(timeout); + + return 0; + case FW_MGMT_IOC_MODE_SWITCH: + if (!fw_mgmt->intf_fw_loaded) { + dev_err(fw_mgmt->parent, + "Firmware not loaded for mode-switch\n"); + return -EPERM; + } + + /* + * Disallow new ioctls as the fw-core bundle driver is going to + * get disconnected soon and the character device will get + * removed. + */ + fw_mgmt->mode_switch_started = true; + + ret = gb_interface_request_mode_switch(fw_mgmt->connection->intf); + if (ret) { + dev_err(fw_mgmt->parent, "Mode-switch failed: %d\n", + ret); + fw_mgmt->mode_switch_started = false; + return ret; + } + + return 0; + default: + return -ENOTTY; + } +} + +static long fw_mgmt_ioctl_unlocked(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct fw_mgmt *fw_mgmt = file->private_data; + struct gb_bundle *bundle = fw_mgmt->connection->bundle; + int ret = -ENODEV; + + /* + * Serialize ioctls. + * + * We don't want the user to do few operations in parallel. For example, + * updating Interface firmware in parallel for the same Interface. There + * is no need to do things in parallel for speed and we can avoid having + * complicated code for now. + * + * This is also used to protect ->disabled, which is used to check if + * the connection is getting disconnected, so that we don't start any + * new operations. + */ + mutex_lock(&fw_mgmt->mutex); + if (!fw_mgmt->disabled) { + ret = gb_pm_runtime_get_sync(bundle); + if (!ret) { + ret = fw_mgmt_ioctl(fw_mgmt, cmd, (void __user *)arg); + gb_pm_runtime_put_autosuspend(bundle); + } + } + mutex_unlock(&fw_mgmt->mutex); + + return ret; +} + +static const struct file_operations fw_mgmt_fops = { + .owner = THIS_MODULE, + .open = fw_mgmt_open, + .release = fw_mgmt_release, + .unlocked_ioctl = fw_mgmt_ioctl_unlocked, +}; + +int gb_fw_mgmt_request_handler(struct gb_operation *op) +{ + u8 type = op->type; + + switch (type) { + case GB_FW_MGMT_TYPE_LOADED_FW: + return fw_mgmt_interface_fw_loaded_operation(op); + case GB_FW_MGMT_TYPE_BACKEND_FW_UPDATED: + return fw_mgmt_backend_fw_updated_operation(op); + default: + dev_err(&op->connection->bundle->dev, + "unsupported request: %u\n", type); + return -EINVAL; + } +} + +int gb_fw_mgmt_connection_init(struct gb_connection *connection) +{ + struct fw_mgmt *fw_mgmt; + int ret, minor; + + if (!connection) + return 0; + + fw_mgmt = kzalloc(sizeof(*fw_mgmt), GFP_KERNEL); + if (!fw_mgmt) + return -ENOMEM; + + fw_mgmt->parent = &connection->bundle->dev; + fw_mgmt->timeout_jiffies = msecs_to_jiffies(FW_MGMT_TIMEOUT_MS); + fw_mgmt->connection = connection; + + gb_connection_set_data(connection, fw_mgmt); + init_completion(&fw_mgmt->completion); + ida_init(&fw_mgmt->id_map); + mutex_init(&fw_mgmt->mutex); + kref_init(&fw_mgmt->kref); + + mutex_lock(&list_mutex); + list_add(&fw_mgmt->node, &fw_mgmt_list); + mutex_unlock(&list_mutex); + + ret = gb_connection_enable(connection); + if (ret) + goto err_list_del; + + minor = ida_simple_get(&fw_mgmt_minors_map, 0, NUM_MINORS, GFP_KERNEL); + if (minor < 0) { + ret = minor; + goto err_connection_disable; + } + + /* Add a char device to allow userspace to interact with fw-mgmt */ + fw_mgmt->dev_num = MKDEV(MAJOR(fw_mgmt_dev_num), minor); + cdev_init(&fw_mgmt->cdev, &fw_mgmt_fops); + + ret = cdev_add(&fw_mgmt->cdev, fw_mgmt->dev_num, 1); + if (ret) + goto err_remove_ida; + + /* Add a soft link to the previously added char-dev within the bundle */ + fw_mgmt->class_device = device_create(fw_mgmt_class, fw_mgmt->parent, + fw_mgmt->dev_num, NULL, + "gb-fw-mgmt-%d", minor); + if (IS_ERR(fw_mgmt->class_device)) { + ret = PTR_ERR(fw_mgmt->class_device); + goto err_del_cdev; + } + + return 0; + +err_del_cdev: + cdev_del(&fw_mgmt->cdev); +err_remove_ida: + ida_simple_remove(&fw_mgmt_minors_map, minor); +err_connection_disable: + gb_connection_disable(connection); +err_list_del: + mutex_lock(&list_mutex); + list_del(&fw_mgmt->node); + mutex_unlock(&list_mutex); + + put_fw_mgmt(fw_mgmt); + + return ret; +} + +void gb_fw_mgmt_connection_exit(struct gb_connection *connection) +{ + struct fw_mgmt *fw_mgmt; + + if (!connection) + return; + + fw_mgmt = gb_connection_get_data(connection); + + device_destroy(fw_mgmt_class, fw_mgmt->dev_num); + cdev_del(&fw_mgmt->cdev); + ida_simple_remove(&fw_mgmt_minors_map, MINOR(fw_mgmt->dev_num)); + + /* + * Disallow any new ioctl operations on the char device and wait for + * existing ones to finish. + */ + mutex_lock(&fw_mgmt->mutex); + fw_mgmt->disabled = true; + mutex_unlock(&fw_mgmt->mutex); + + /* All pending greybus operations should have finished by now */ + gb_connection_disable(fw_mgmt->connection); + + /* Disallow new users to get access to the fw_mgmt structure */ + mutex_lock(&list_mutex); + list_del(&fw_mgmt->node); + mutex_unlock(&list_mutex); + + /* + * All current users of fw_mgmt would have taken a reference to it by + * now, we can drop our reference and wait the last user will get + * fw_mgmt freed. + */ + put_fw_mgmt(fw_mgmt); +} + +int fw_mgmt_init(void) +{ + int ret; + + fw_mgmt_class = class_create(THIS_MODULE, "gb_fw_mgmt"); + if (IS_ERR(fw_mgmt_class)) + return PTR_ERR(fw_mgmt_class); + + ret = alloc_chrdev_region(&fw_mgmt_dev_num, 0, NUM_MINORS, + "gb_fw_mgmt"); + if (ret) + goto err_remove_class; + + return 0; + +err_remove_class: + class_destroy(fw_mgmt_class); + return ret; +} + +void fw_mgmt_exit(void) +{ + unregister_chrdev_region(fw_mgmt_dev_num, NUM_MINORS); + class_destroy(fw_mgmt_class); + ida_destroy(&fw_mgmt_minors_map); +} |