}
case FFS_CLOSING:
break;
+ case FFS_DEACTIVATED:
+ break;
}
mutex_unlock(&ffs->mutex);
struct ffs_file_perms perms;
umode_t root_mode;
const char *dev_name;
+ bool no_disconnect;
struct ffs_data *ffs_data;
};
/* Interpret option */
switch (eq - opts) {
+ case 13:
+ if (!memcmp(opts, "no_disconnect", 13))
+ data->no_disconnect = !!value;
+ else
+ goto invalid;
+ break;
case 5:
if (!memcmp(opts, "rmode", 5))
data->root_mode = (value & 0555) | S_IFDIR;
.gid = GLOBAL_ROOT_GID,
},
.root_mode = S_IFDIR | 0500,
+ .no_disconnect = false,
};
struct dentry *rv;
int ret;
if (unlikely(!ffs))
return ERR_PTR(-ENOMEM);
ffs->file_perms = data.perms;
+ ffs->no_disconnect = data.no_disconnect;
ffs->dev_name = kstrdup(dev_name, GFP_KERNEL);
if (unlikely(!ffs->dev_name)) {
kill_litter_super(sb);
if (sb->s_fs_info) {
ffs_release_dev(sb->s_fs_info);
+ ffs_data_closed(sb->s_fs_info);
ffs_data_put(sb->s_fs_info);
}
}
ENTER();
atomic_inc(&ffs->ref);
- atomic_inc(&ffs->opened);
+ if (atomic_add_return(1, &ffs->opened) == 1 &&
+ ffs->state == FFS_DEACTIVATED) {
+ ffs->state = FFS_CLOSING;
+ ffs_data_reset(ffs);
+ }
}
static void ffs_data_put(struct ffs_data *ffs)
ENTER();
if (atomic_dec_and_test(&ffs->opened)) {
+ if (ffs->no_disconnect) {
+ ffs->state = FFS_DEACTIVATED;
+ if (ffs->epfiles) {
+ ffs_epfiles_destroy(ffs->epfiles,
+ ffs->eps_count);
+ ffs->epfiles = NULL;
+ }
+ if (ffs->setup_state == FFS_SETUP_PENDING)
+ __ffs_ep0_stall(ffs);
+ } else {
+ ffs->state = FFS_CLOSING;
+ ffs_data_reset(ffs);
+ }
+ }
+ if (atomic_read(&ffs->opened) < 0) {
ffs->state = FFS_CLOSING;
ffs_data_reset(ffs);
}
kfree(epfiles);
}
-
static void ffs_func_eps_disable(struct ffs_function *func)
{
struct ffs_ep *ep = func->eps;
/* pending requests get nuked */
if (likely(ep->ep))
usb_ep_disable(ep->ep);
- epfile->ep = NULL;
-
++ep;
- ++epfile;
+
+ if (epfile) {
+ epfile->ep = NULL;
+ ++epfile;
+ }
} while (--count);
spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
}
/* Other USB function hooks *************************************************/
+static void ffs_reset_work(struct work_struct *work)
+{
+ struct ffs_data *ffs = container_of(work,
+ struct ffs_data, reset_work);
+ ffs_data_reset(ffs);
+}
+
static int ffs_func_set_alt(struct usb_function *f,
unsigned interface, unsigned alt)
{
if (ffs->func)
ffs_func_eps_disable(ffs->func);
+ if (ffs->state == FFS_DEACTIVATED) {
+ ffs->state = FFS_CLOSING;
+ INIT_WORK(&ffs->reset_work, ffs_reset_work);
+ schedule_work(&ffs->reset_work);
+ return -ENODEV;
+ }
+
if (ffs->state != FFS_ACTIVE)
return -ENODEV;
#include <linux/usb/composite.h>
#include <linux/list.h>
#include <linux/mutex.h>
+#include <linux/workqueue.h>
#ifdef VERBOSE_DEBUG
#ifndef pr_vdebug
FFS_ACTIVE,
/*
+ * Function is visible to host, but it's not functional. All
+ * setup requests are stalled and transfers on another endpoints
+ * are refused. All epfiles, except ep0, are deleted so there
+ * is no way to perform any operations on them.
+ *
+ * This state is set after closing all functionfs files, when
+ * mount parameter "no_disconnect=1" has been set. Function will
+ * remain in deactivated state until filesystem is umounted or
+ * ep0 is opened again. In the second case functionfs state will
+ * be reset, and it will be ready for descriptors and strings
+ * writing.
+ *
+ * This is useful only when functionfs is composed to gadget
+ * with another function which can perform some critical
+ * operations, and it's strongly desired to have this operations
+ * completed, even after functionfs files closure.
+ */
+ FFS_DEACTIVATED,
+
+ /*
* All endpoints have been closed. This state is also set if
* we encounter an unrecoverable error. The only
* unrecoverable error is situation when after reading strings
kgid_t gid;
} file_perms;
+ bool no_disconnect;
+ struct work_struct reset_work;
+
/*
* The endpoint files, filled by ffs_epfiles_create(),
* destroyed by ffs_epfiles_destroy().