blob: 3cd6cf0a656b8872704388b570f9c7e51c4a3fbe [file] [log] [blame]
/*
* 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);
}