leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

usb: gadget: f_midi: allow resetting index option

Browse Source 
Unlike the other integral options supported by the MIDI gadget, index is
a signed integer and defaults to -1, which means "choose any sound card
index".  The generic store routine parses input into a u32 which fails
to properly read -1 if an attempt is made to set the value to the
default.

Add a new macro block for signed values to fix this, and use the correct
format string for unsigned values.

Signed-off-by: John Keeping <john@metanate.com>
Link: https://lore.kernel.org/r/20211029134115.351008-1-john@metanate.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
John Keeping 2021-10-29 14:41:14 +01:00 committed by Greg Kroah-Hartman
parent f057a1d4f0
commit d429976170
1 changed files with 46 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
drivers/usb/gadget/function/f_midi.c
View File

@ -1097,7 +1097,7 @@ static ssize_t f_midi_opts_##name##_show(struct config_item *item, char *page) \
int result; \
\
mutex_lock(&opts->lock); \
result = sprintf(page, "%d\n", opts->name); \
result = sprintf(page, "%u\n", opts->name); \
mutex_unlock(&opts->lock); \
\
return result; \
@ -1134,7 +1134,51 @@ end: \
\
CONFIGFS_ATTR(f_midi_opts_, name);
F_MIDI_OPT(index, true, SNDRV_CARDS);
#define F_MIDI_OPT_SIGNED(name, test_limit, limit) \
static ssize_t f_midi_opts_##name##_show(struct config_item *item, char *page) \
{ \
struct f_midi_opts *opts = to_f_midi_opts(item); \
int result; \
\
mutex_lock(&opts->lock); \
result = sprintf(page, "%d\n", opts->name); \
mutex_unlock(&opts->lock); \
\
return result; \
} \
\
static ssize_t f_midi_opts_##name##_store(struct config_item *item, \
const char *page, size_t len) \
{ \
struct f_midi_opts *opts = to_f_midi_opts(item); \
int ret; \
s32 num; \
\
mutex_lock(&opts->lock); \
if (opts->refcnt > 1) { \
ret = -EBUSY; \
goto end; \
} \
\
ret = kstrtos32(page, 0, &num); \
if (ret) \
goto end; \
\
if (test_limit && num > limit) { \
ret = -EINVAL; \
goto end; \
} \
opts->name = num; \
ret = len; \
\
end: \
mutex_unlock(&opts->lock); \
return ret; \
} \
\
CONFIGFS_ATTR(f_midi_opts_, name);
F_MIDI_OPT_SIGNED(index, true, SNDRV_CARDS);
F_MIDI_OPT(buflen, false, 0);
F_MIDI_OPT(qlen, false, 0);
F_MIDI_OPT(in_ports, true, MAX_PORTS);