From mboxrd@z Thu Jan 1 00:00:00 1970 From: rmk+kernel@armlinux.org.uk (Russell King) Date: Tue, 08 Nov 2016 12:25:00 +0000 Subject: [PATCH RFC 01/12] drm/i2c: tda998x: avoid race in tda998x_encoder_mode_set() In-Reply-To: <20161108122420.GP1041@n2100.armlinux.org.uk> References: <20161108122420.GP1041@n2100.armlinux.org.uk> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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. 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 088900d78ceb..1cc0433ce9d5 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); } } -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King Subject: [PATCH RFC 01/12] drm/i2c: tda998x: avoid race in tda998x_encoder_mode_set() Date: Tue, 08 Nov 2016 12:25:00 +0000 Message-ID: References: <20161108122420.GP1041@n2100.armlinux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161108122420.GP1041@n2100.armlinux.org.uk> Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Brian Starkey , Liviu Dudau , Jyri Sarha Cc: linux-arm-kernel@lists.infradead.org, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org 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. 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 088900d78ceb..1cc0433ce9d5 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); } } -- 2.7.4