usb: gadget: FunctionFS: convert to new function interface with backward compatibility
This is required in order to integrate configfs support.
f_fs needs to be a separately compiled module and so it needs to use the new
interface.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/u_fs.h b/drivers/usb/gadget/u_fs.h
index 2d00f9d..d60a9dd 100644
--- a/drivers/usb/gadget/u_fs.h
+++ b/drivers/usb/gadget/u_fs.h
@@ -20,6 +20,22 @@
#include <linux/list.h>
#include <linux/mutex.h>
+#ifdef VERBOSE_DEBUG
+#ifndef pr_vdebug
+# define pr_vdebug pr_debug
+#endif /* pr_vdebug */
+# define ffs_dump_mem(prefix, ptr, len) \
+ print_hex_dump_bytes(pr_fmt(prefix ": "), DUMP_PREFIX_NONE, ptr, len)
+#else
+#ifndef pr_vdebug
+# define pr_vdebug(...) do { } while (0)
+#endif /* pr_vdebug */
+# define ffs_dump_mem(prefix, ptr, len) do { } while (0)
+#endif /* VERBOSE_DEBUG */
+
+#define ENTER() pr_vdebug("%s()\n", __func__)
+
+
struct ffs_dev {
const char *name;
bool mounted;
@@ -30,6 +46,8 @@
int (*ffs_ready_callback)(struct ffs_data *ffs);
void (*ffs_closed_callback)(struct ffs_data *ffs);
+ void *(*ffs_acquire_dev_callback)(struct ffs_dev *dev);
+ void (*ffs_release_dev_callback)(struct ffs_dev *dev);
};
extern struct mutex ffs_lock;
@@ -49,4 +67,200 @@
int ffs_single_dev(struct ffs_dev *dev);
void ffs_free_dev(struct ffs_dev *dev);
+struct ffs_epfile;
+struct ffs_function;
+
+enum ffs_state {
+ /*
+ * Waiting for descriptors and strings.
+ *
+ * In this state no open(2), read(2) or write(2) on epfiles
+ * may succeed (which should not be the problem as there
+ * should be no such files opened in the first place).
+ */
+ FFS_READ_DESCRIPTORS,
+ FFS_READ_STRINGS,
+
+ /*
+ * We've got descriptors and strings. We are or have called
+ * functionfs_ready_callback(). functionfs_bind() may have
+ * been called but we don't know.
+ *
+ * This is the only state in which operations on epfiles may
+ * succeed.
+ */
+ FFS_ACTIVE,
+
+ /*
+ * 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
+ * from user space we fail to initialise epfiles or
+ * functionfs_ready_callback() returns with error (<0).
+ *
+ * In this state no open(2), read(2) or write(2) (both on ep0
+ * as well as epfile) may succeed (at this point epfiles are
+ * unlinked and all closed so this is not a problem; ep0 is
+ * also closed but ep0 file exists and so open(2) on ep0 must
+ * fail).
+ */
+ FFS_CLOSING
+};
+
+enum ffs_setup_state {
+ /* There is no setup request pending. */
+ FFS_NO_SETUP,
+ /*
+ * User has read events and there was a setup request event
+ * there. The next read/write on ep0 will handle the
+ * request.
+ */
+ FFS_SETUP_PENDING,
+ /*
+ * There was event pending but before user space handled it
+ * some other event was introduced which canceled existing
+ * setup. If this state is set read/write on ep0 return
+ * -EIDRM. This state is only set when adding event.
+ */
+ FFS_SETUP_CANCELED
+};
+
+struct ffs_data {
+ struct usb_gadget *gadget;
+
+ /*
+ * Protect access read/write operations, only one read/write
+ * at a time. As a consequence protects ep0req and company.
+ * While setup request is being processed (queued) this is
+ * held.
+ */
+ struct mutex mutex;
+
+ /*
+ * Protect access to endpoint related structures (basically
+ * usb_ep_queue(), usb_ep_dequeue(), etc. calls) except for
+ * endpoint zero.
+ */
+ spinlock_t eps_lock;
+
+ /*
+ * XXX REVISIT do we need our own request? Since we are not
+ * handling setup requests immediately user space may be so
+ * slow that another setup will be sent to the gadget but this
+ * time not to us but another function and then there could be
+ * a race. Is that the case? Or maybe we can use cdev->req
+ * after all, maybe we just need some spinlock for that?
+ */
+ struct usb_request *ep0req; /* P: mutex */
+ struct completion ep0req_completion; /* P: mutex */
+ int ep0req_status; /* P: mutex */
+
+ /* reference counter */
+ atomic_t ref;
+ /* how many files are opened (EP0 and others) */
+ atomic_t opened;
+
+ /* EP0 state */
+ enum ffs_state state;
+
+ /*
+ * Possible transitions:
+ * + FFS_NO_SETUP -> FFS_SETUP_PENDING -- P: ev.waitq.lock
+ * happens only in ep0 read which is P: mutex
+ * + FFS_SETUP_PENDING -> FFS_NO_SETUP -- P: ev.waitq.lock
+ * happens only in ep0 i/o which is P: mutex
+ * + FFS_SETUP_PENDING -> FFS_SETUP_CANCELED -- P: ev.waitq.lock
+ * + FFS_SETUP_CANCELED -> FFS_NO_SETUP -- cmpxchg
+ */
+ enum ffs_setup_state setup_state;
+
+#define FFS_SETUP_STATE(ffs) \
+ ((enum ffs_setup_state)cmpxchg(&(ffs)->setup_state, \
+ FFS_SETUP_CANCELED, FFS_NO_SETUP))
+
+ /* Events & such. */
+ struct {
+ u8 types[4];
+ unsigned short count;
+ /* XXX REVISIT need to update it in some places, or do we? */
+ unsigned short can_stall;
+ struct usb_ctrlrequest setup;
+
+ wait_queue_head_t waitq;
+ } ev; /* the whole structure, P: ev.waitq.lock */
+
+ /* Flags */
+ unsigned long flags;
+#define FFS_FL_CALL_CLOSED_CALLBACK 0
+#define FFS_FL_BOUND 1
+
+ /* Active function */
+ struct ffs_function *func;
+
+ /*
+ * Device name, write once when file system is mounted.
+ * Intended for user to read if she wants.
+ */
+ const char *dev_name;
+ /* Private data for our user (ie. gadget). Managed by user. */
+ void *private_data;
+
+ /* filled by __ffs_data_got_descs() */
+ /*
+ * Real descriptors are 16 bytes after raw_descs (so you need
+ * to skip 16 bytes (ie. ffs->raw_descs + 16) to get to the
+ * first full speed descriptor). raw_descs_length and
+ * raw_fs_descs_length do not have those 16 bytes added.
+ */
+ const void *raw_descs;
+ unsigned raw_descs_length;
+ unsigned raw_fs_descs_length;
+ unsigned fs_descs_count;
+ unsigned hs_descs_count;
+
+ unsigned short strings_count;
+ unsigned short interfaces_count;
+ unsigned short eps_count;
+ unsigned short _pad1;
+
+ /* filled by __ffs_data_got_strings() */
+ /* ids in stringtabs are set in functionfs_bind() */
+ const void *raw_strings;
+ struct usb_gadget_strings **stringtabs;
+
+ /*
+ * File system's super block, write once when file system is
+ * mounted.
+ */
+ struct super_block *sb;
+
+ /* File permissions, written once when fs is mounted */
+ struct ffs_file_perms {
+ umode_t mode;
+ kuid_t uid;
+ kgid_t gid;
+ } file_perms;
+
+ /*
+ * The endpoint files, filled by ffs_epfiles_create(),
+ * destroyed by ffs_epfiles_destroy().
+ */
+ struct ffs_epfile *epfiles;
+};
+
+
+#ifndef USB_FFS_INCLUDED
+struct f_fs_opts {
+ struct usb_function_instance func_inst;
+ struct ffs_dev *dev;
+ unsigned refcnt;
+ bool no_configfs;
+};
+
+static inline struct f_fs_opts *to_f_fs_opts(struct usb_function_instance *fi)
+{
+ return container_of(fi, struct f_fs_opts, func_inst);
+}
+#endif
+
#endif /* U_FFS_H */