From 6d30c0f728cac32ce8bf3d48ef6df485e0c641f1 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 23 Oct 2016 11:31:44 +0100 Subject: [PATCH] drm/i2c: tda998x: avoid race in tda998x_encoder_mode_set() As priv->audio_params can now be changed at run time, we need to be more careful about how we deal with a mode set. We must take the audio lock while checking if there's a valid audio configuration. However, it's slightly worse than that - during mode set, we mute the audio, and it must not be unmuted until we have finished the mode set. It is possible that the audio side may start while a mode set is in progress, so take the audio_mutex lock around the whole mode setting procedure. Tested-by: Jon Medhurst Acked-by: Jon Medhurst Tested-by: Jyri Sarha Signed-off-by: Russell King --- drivers/gpu/drm/i2c/tda998x_drv.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c index 168c0b4b8f47..9184487b10ad 100644 --- a/drivers/gpu/drm/i2c/tda998x_drv.c +++ b/drivers/gpu/drm/i2c/tda998x_drv.c @@ -1074,13 +1074,12 @@ tda998x_encoder_mode_set(struct drm_encoder *encoder, tda998x_write_avi(priv, adjusted_mode); - if (priv->audio_params.format != AFMT_UNUSED) { - mutex_lock(&priv->audio_mutex); + mutex_lock(&priv->audio_mutex); + if (priv->audio_params.format != AFMT_UNUSED) tda998x_configure_audio(priv, &priv->audio_params, adjusted_mode->clock); - mutex_unlock(&priv->audio_mutex); - } + mutex_unlock(&priv->audio_mutex); } }