ALSA: mpu401: Fix missing initialization of irq field

The irq field of struct snd_mpu401 is supposed to be initialized to -1.
Since it's set to zero as of now, a probing error before the irq
installation results in a kernel warning "Trying to free already-free
IRQ 0".

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=44821
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/sound/drivers/mpu401/mpu401_uart.c b/sound/drivers/mpu401/mpu401_uart.c
index 1cff331a228e..4608c2ca43f8 100644
--- a/sound/drivers/mpu401/mpu401_uart.c
+++ b/sound/drivers/mpu401/mpu401_uart.c
@@ -554,6 +554,7 @@ int snd_mpu401_uart_new(struct snd_card *card, int device,
         spin_lock_init(&mpu->output_lock);
         spin_lock_init(&mpu->timer_lock);
         mpu->hardware = hardware;
+        mpu->irq = -1;
         if (! (info_flags & MPU401_INFO_INTEGRATED)) {
                 int res_size = hardware == MPU401_HW_PC98II ? 4 : 2;
                 mpu->res = request_region(port, res_size, "MPU401 UART");