diff options
| author | John Keeping <jkeeping@inmusicbrands.com> | 2025-09-15 10:42:19 +0100 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2025-09-15 12:33:53 +0200 |
| commit | 84973249011fda3ff292f83439a062fec81ef982 (patch) | |
| tree | a6225edb11775ebc1e0e4f2e8f094ee3fbe71d2e | |
| parent | c29287bb32bc72a037c34d84a160060a6122b7ed (diff) | |
ALSA: serial-generic: remove shared static buffer
If multiple instances of this driver are instantiated and try to send
concurrently then the single static buffer snd_serial_generic_tx_work()
will cause corruption in the data output.
Move the buffer into the per-instance driver data to avoid this.
Signed-off-by: John Keeping <jkeeping@inmusicbrands.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
| -rw-r--r-- | sound/drivers/serial-generic.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/sound/drivers/serial-generic.c b/sound/drivers/serial-generic.c index 21ae053c0576..766206c6ca75 100644 --- a/sound/drivers/serial-generic.c +++ b/sound/drivers/serial-generic.c @@ -37,6 +37,8 @@ MODULE_LICENSE("GPL"); #define SERIAL_TX_STATE_ACTIVE 1 #define SERIAL_TX_STATE_WAKEUP 2 +#define INTERNAL_BUF_SIZE 256 + struct snd_serial_generic { struct serdev_device *serdev; @@ -51,6 +53,7 @@ struct snd_serial_generic { struct work_struct tx_work; unsigned long tx_state; + char tx_buf[INTERNAL_BUF_SIZE]; }; static void snd_serial_generic_tx_wakeup(struct snd_serial_generic *drvdata) @@ -61,11 +64,8 @@ static void snd_serial_generic_tx_wakeup(struct snd_serial_generic *drvdata) schedule_work(&drvdata->tx_work); } -#define INTERNAL_BUF_SIZE 256 - static void snd_serial_generic_tx_work(struct work_struct *work) { - static char buf[INTERNAL_BUF_SIZE]; int num_bytes; struct snd_serial_generic *drvdata = container_of(work, struct snd_serial_generic, tx_work); @@ -78,8 +78,10 @@ static void snd_serial_generic_tx_work(struct work_struct *work) if (!test_bit(SERIAL_MODE_OUTPUT_OPEN, &drvdata->filemode)) break; - num_bytes = snd_rawmidi_transmit_peek(substream, buf, INTERNAL_BUF_SIZE); - num_bytes = serdev_device_write_buf(drvdata->serdev, buf, num_bytes); + num_bytes = snd_rawmidi_transmit_peek(substream, drvdata->tx_buf, + INTERNAL_BUF_SIZE); + num_bytes = serdev_device_write_buf(drvdata->serdev, drvdata->tx_buf, + num_bytes); if (!num_bytes) break; |