diff options
Diffstat (limited to 'drivers/hid/hid-core.c')
| -rw-r--r-- | drivers/hid/hid-core.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index b0f2f459f59..a1b248cea5b 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1128,7 +1128,8 @@ static void hid_output_field(const struct hid_device *hid, } /* - * Create a report. + * Create a report. 'data' has to be allocated using + * hid_alloc_report_buf() so that it has proper size. */ void hid_output_report(struct hid_report *report, __u8 *data) @@ -1145,6 +1146,22 @@ void hid_output_report(struct hid_report *report, __u8 *data) EXPORT_SYMBOL_GPL(hid_output_report); /* + * Allocator for buffer that is going to be passed to hid_output_report() + */ +u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags) +{ + /* + * 7 extra bytes are necessary to achieve proper functionality + * of implement() working on 8 byte chunks + */ + + int len = ((report->size - 1) >> 3) + 1 + (report->id > 0) + 7; + + return kmalloc(len, flags); +} +EXPORT_SYMBOL_GPL(hid_alloc_report_buf); + +/* * Set a field value. The report this field belongs to has to be * created and transferred to the device, to set this value in the * device. |