From 83f8bf4b837b0e3417f0e5c717a43fcf71ecc992 Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Tue, 16 Apr 2019 14:43:26 +0200 Subject: [PATCH] drm/tegra: hdmi: Setup audio only if configured The audio configuration is only valid if the HDMI codec has been properly set up. Do not attempt to set up audio before that happens because it causes a division by zero. Note that this is only problematic on Tegra20 and Tegra30. Later chips implement the division instructions which return zero when dividing by zero and don't throw an exception. Fixes: db5adf4d6dce ("drm/tegra: hdmi: Fix audio to work with any pixel clock rate") Reported-by: Marcel Ziswiler Tested-by: Dmitry Osipenko Signed-off-by: Thierry Reding --- drivers/gpu/drm/tegra/hdmi.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/tegra/hdmi.c b/drivers/gpu/drm/tegra/hdmi.c index 47c55974756d..d23c4bfde790 100644 --- a/drivers/gpu/drm/tegra/hdmi.c +++ b/drivers/gpu/drm/tegra/hdmi.c @@ -1260,9 +1260,15 @@ static void tegra_hdmi_encoder_enable(struct drm_encoder *encoder) hdmi->dvi = !tegra_output_is_hdmi(output); if (!hdmi->dvi) { - err = tegra_hdmi_setup_audio(hdmi); - if (err < 0) - hdmi->dvi = true; + /* + * Make sure that the audio format has been configured before + * enabling audio, otherwise we may try to divide by zero. + */ + if (hdmi->format.sample_rate > 0) { + err = tegra_hdmi_setup_audio(hdmi); + if (err < 0) + hdmi->dvi = true; + } } if (hdmi->config->has_hda)