diff options
author | Andrzej Pietrasiewicz <andrzej.p@samsung.com> | 2013-12-03 14:15:33 (GMT) |
---|---|---|
committer | Felipe Balbi <balbi@ti.com> | 2013-12-12 19:43:39 (GMT) |
commit | 5920cda627688c3229fd63157ff031f3f174175e (patch) | |
tree | ebdc858c1a54f56a23202f714999444f69b36cf1 /drivers/usb/gadget/f_fs.c | |
parent | 4b187fceec3c731815ff8e6a7317fd5ba50d1d5d (diff) | |
download | linux-5920cda627688c3229fd63157ff031f3f174175e.tar.xz |
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>
Diffstat (limited to 'drivers/usb/gadget/f_fs.c')
-rw-r--r-- | drivers/usb/gadget/f_fs.c | 422 |
1 files changed, 213 insertions, 209 deletions
diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c index d17930d..8d318ea 100644 --- a/drivers/usb/gadget/f_fs.c +++ b/drivers/usb/gadget/f_fs.c @@ -22,6 +22,7 @@ #include <linux/pagemap.h> #include <linux/export.h> #include <linux/hid.h> +#include <linux/module.h> #include <asm/unaligned.h> #include <linux/usb/composite.h> @@ -57,210 +58,6 @@ #define vla_ptr(ptr, groupname, name) \ ((void *) ((char *)ptr + groupname##_##name##__offset)) -/* Debugging ****************************************************************/ - -#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__) - - -/* The data structure and setup file ****************************************/ - -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 - * ffs_ready(). 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 - * ffs_ready() 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_epfile; -struct ffs_function; - -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; -}; - /* Reference counter handling */ static void ffs_data_get(struct ffs_data *ffs); static void ffs_data_put(struct ffs_data *ffs); @@ -300,15 +97,19 @@ static struct ffs_function *ffs_func_from_usb(struct usb_function *f) return container_of(f, struct ffs_function, function); } +#ifdef USB_FFS_INCLUDED static void ffs_func_free(struct ffs_function *func); +#endif static void ffs_func_eps_disable(struct ffs_function *func); static int __must_check ffs_func_eps_enable(struct ffs_function *func); static int ffs_func_bind(struct usb_configuration *, struct usb_function *); -static void ffs_func_unbind(struct usb_configuration *, +#ifdef USB_FFS_INCLUDED +static void old_ffs_func_unbind(struct usb_configuration *, struct usb_function *); +#endif static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned); static void ffs_func_disable(struct usb_function *); static int ffs_func_setup(struct usb_function *, @@ -364,6 +165,9 @@ ffs_sb_create_file(struct super_block *sb, const char *name, void *data, /* Devices management *******************************************************/ DEFINE_MUTEX(ffs_lock); +#ifndef USB_FFS_INCLUDED +EXPORT_SYMBOL(ffs_lock); +#endif static struct ffs_dev *ffs_find_dev(const char *name); static void *ffs_acquire_dev(const char *dev_name); @@ -1499,6 +1303,8 @@ static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count) kfree(epfiles); } +#ifdef USB_FFS_INCLUDED + static int functionfs_bind_config(struct usb_composite_dev *cdev, struct usb_configuration *c, struct ffs_data *ffs) @@ -1516,7 +1322,7 @@ static int functionfs_bind_config(struct usb_composite_dev *cdev, func->function.strings = ffs->stringtabs; func->function.bind = ffs_func_bind; - func->function.unbind = ffs_func_unbind; + func->function.unbind = old_ffs_func_unbind; func->function.set_alt = ffs_func_set_alt; func->function.disable = ffs_func_disable; func->function.setup = ffs_func_setup; @@ -1565,6 +1371,8 @@ static void ffs_func_free(struct ffs_function *func) kfree(func); } +#endif + static void ffs_func_eps_disable(struct ffs_function *func) { struct ffs_ep *ep = func->eps; @@ -2227,8 +2035,59 @@ static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep, return 0; } -static int ffs_func_bind(struct usb_configuration *c, - struct usb_function *f) +#ifndef USB_FFS_INCLUDED +static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f, + struct usb_configuration *c) +{ + struct ffs_function *func = ffs_func_from_usb(f); + struct f_fs_opts *ffs_opts = + container_of(f->fi, struct f_fs_opts, func_inst); + int ret; + + ENTER(); + + /* + * Legacy gadget triggers binding in functionfs_ready_callback, + * which already uses locking; taking the same lock here would + * cause a deadlock. + * + * Configfs-enabled gadgets however do need ffs_dev_lock. + */ + if (!ffs_opts->no_configfs) + ffs_dev_lock(); + ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV; + func->ffs = ffs_opts->dev->ffs_data; + if (!ffs_opts->no_configfs) + ffs_dev_unlock(); + if (ret) + return ERR_PTR(ret); + + func->conf = c; + func->gadget = c->cdev->gadget; + + ffs_data_get(func->ffs); + + /* + * in drivers/usb/gadget/configfs.c:configfs_composite_bind() + * configurations are bound in sequence with list_for_each_entry, + * in each configuration its functions are bound in sequence + * with list_for_each_entry, so we assume no race condition + * with regard to ffs_opts->bound access + */ + if (!ffs_opts->refcnt) { + ret = functionfs_bind(func->ffs, c->cdev); + if (ret) + return ERR_PTR(ret); + } + ffs_opts->refcnt++; + func->function.strings = func->ffs->stringtabs; + + return ffs_opts; +} +#endif + +static int _ffs_func_bind(struct usb_configuration *c, + struct usb_function *f) { struct ffs_function *func = ffs_func_from_usb(f); struct ffs_data *ffs = func->ffs; @@ -2328,10 +2187,25 @@ error: return ret; } +static int ffs_func_bind(struct usb_configuration *c, + struct usb_function *f) +{ +#ifndef USB_FFS_INCLUDED + struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c); + + if (IS_ERR(ffs_opts)) + return PTR_ERR(ffs_opts); +#endif + + return _ffs_func_bind(c, f); +} + /* Other USB function hooks *************************************************/ -static void ffs_func_unbind(struct usb_configuration *c, +#ifdef USB_FFS_INCLUDED + +static void old_ffs_func_unbind(struct usb_configuration *c, struct usb_function *f) { struct ffs_function *func = ffs_func_from_usb(f); @@ -2349,6 +2223,8 @@ static void ffs_func_unbind(struct usb_configuration *c, ffs_func_free(func); } +#endif + static int ffs_func_set_alt(struct usb_function *f, unsigned interface, unsigned alt) { @@ -2523,6 +2399,116 @@ static struct ffs_dev *ffs_find_dev(const char *name) return _ffs_find_dev(name); } +/* Function registration interface ******************************************/ + +#ifndef USB_FFS_INCLUDED + +static void ffs_free_inst(struct usb_function_instance *f) +{ + struct f_fs_opts *opts; + + opts = to_f_fs_opts(f); + ffs_dev_lock(); + ffs_free_dev(opts->dev); + ffs_dev_unlock(); + kfree(opts); +} + +static struct usb_function_instance *ffs_alloc_inst(void) +{ + struct f_fs_opts *opts; + struct ffs_dev *dev; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) + return ERR_PTR(-ENOMEM); + + opts->func_inst.free_func_inst = ffs_free_inst; + ffs_dev_lock(); + dev = ffs_alloc_dev(); + ffs_dev_unlock(); + if (IS_ERR(dev)) { + kfree(opts); + return ERR_CAST(dev); + } + opts->dev = dev; + + return &opts->func_inst; +} + +static void ffs_free(struct usb_function *f) +{ + kfree(ffs_func_from_usb(f)); +} + +static void ffs_func_unbind(struct usb_configuration *c, + struct usb_function *f) +{ + struct ffs_function *func = ffs_func_from_usb(f); + struct ffs_data *ffs = func->ffs; + struct f_fs_opts *opts = + container_of(f->fi, struct f_fs_opts, func_inst); + struct ffs_ep *ep = func->eps; + unsigned count = ffs->eps_count; + unsigned long flags; + + ENTER(); + if (ffs->func == func) { + ffs_func_eps_disable(func); + ffs->func = NULL; + } + + if (!--opts->refcnt) + functionfs_unbind(ffs); + + /* cleanup after autoconfig */ + spin_lock_irqsave(&func->ffs->eps_lock, flags); + do { + if (ep->ep && ep->req) + usb_ep_free_request(ep->ep, ep->req); + ep->req = NULL; + ++ep; + } while (--count); + spin_unlock_irqrestore(&func->ffs->eps_lock, flags); + kfree(func->eps); + func->eps = NULL; + /* + * eps, descriptors and interfaces_nums are allocated in the + * same chunk so only one free is required. + */ + func->function.fs_descriptors = NULL; + func->function.hs_descriptors = NULL; + func->interfaces_nums = NULL; + + ffs_event_add(ffs, FUNCTIONFS_UNBIND); +} + +static struct usb_function *ffs_alloc(struct usb_function_instance *fi) +{ + struct ffs_function *func; + + ENTER(); + + func = kzalloc(sizeof(*func), GFP_KERNEL); + if (unlikely(!func)) + return ERR_PTR(-ENOMEM); + + func->function.name = "Function FS Gadget"; + + func->function.bind = ffs_func_bind; + func->function.unbind = ffs_func_unbind; + func->function.set_alt = ffs_func_set_alt; + func->function.disable = ffs_func_disable; + func->function.setup = ffs_func_setup; + func->function.suspend = ffs_func_suspend; + func->function.resume = ffs_func_resume; + func->function.free_func = ffs_free; + + return &func->function; +} + +#endif + /* * ffs_lock must be taken by the caller of this function */ @@ -2581,6 +2567,9 @@ int ffs_name_dev(struct ffs_dev *dev, const char *name) return ret; } +#ifndef USB_FFS_INCLUDED +EXPORT_SYMBOL(ffs_name_dev); +#endif int ffs_single_dev(struct ffs_dev *dev) { @@ -2597,6 +2586,9 @@ int ffs_single_dev(struct ffs_dev *dev) ffs_dev_unlock(); return ret; } +#ifndef USB_FFS_INCLUDED +EXPORT_SYMBOL(ffs_single_dev); +#endif /* * ffs_lock must be taken by the caller of this function @@ -2621,6 +2613,9 @@ static void *ffs_acquire_dev(const char *dev_name) ffs_dev = ERR_PTR(-ENODEV); else if (ffs_dev->mounted) ffs_dev = ERR_PTR(-EBUSY); + else if (ffs_dev->ffs_acquire_dev_callback && + ffs_dev->ffs_acquire_dev_callback(ffs_dev)) + ffs_dev = ERR_PTR(-ENODEV); else ffs_dev->mounted = true; @@ -2638,6 +2633,9 @@ static void ffs_release_dev(struct ffs_data *ffs_data) ffs_dev = ffs_data->private_data; if (ffs_dev) ffs_dev->mounted = false; + + if (ffs_dev->ffs_release_dev_callback) + ffs_dev->ffs_release_dev_callback(ffs_dev); ffs_dev_unlock(); } @@ -2720,3 +2718,9 @@ static char *ffs_prepare_buffer(const char __user *buf, size_t len) return data; } + +#ifndef USB_FFS_INCLUDED +DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Michal Nazarewicz"); +#endif |