From 0c9d0ddd9cf4b43f8b3faf752c5a1aaa665ed099 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Mon, 11 Jul 2022 19:39:16 +0200 Subject: [PATCH] drm/vc4: hdmi: Move audio structure offset checks The HDMI driver unbind hook doesn't have any ALSA-related code anymore, so let's move the ALSA sanity checks and comments we have to some other part of the driver dedicated to ALSA. Acked-by: Thomas Zimmermann Signed-off-by: Maxime Ripard Link: https://lore.kernel.org/r/20220711173939.1132294-47-maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_hdmi.c | 40 ++++++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 6275db4..a130b7d 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -2076,6 +2076,26 @@ static int vc4_hdmi_audio_init(struct vc4_hdmi *vc4_hdmi) int index, len; int ret; + /* + * ASoC makes it a bit hard to retrieve a pointer to the + * vc4_hdmi structure. Registering the card will overwrite our + * device drvdata with a pointer to the snd_soc_card structure, + * which can then be used to retrieve whatever drvdata we want + * to associate. + * + * However, that doesn't fly in the case where we wouldn't + * register an ASoC card (because of an old DT that is missing + * the dmas properties for example), then the card isn't + * registered and the device drvdata wouldn't be set. + * + * We can deal with both cases by making sure a snd_soc_card + * pointer and a vc4_hdmi structure are pointing to the same + * memory address, so we can treat them indistinctly without any + * issue. + */ + BUILD_BUG_ON(offsetof(struct vc4_hdmi_audio, card) != 0); + BUILD_BUG_ON(offsetof(struct vc4_hdmi, audio) != 0); + if (!of_find_property(dev->of_node, "dmas", &len) || !len) { dev_warn(dev, "'dmas' DT property is missing or empty, no HDMI audio\n"); @@ -3082,26 +3102,6 @@ err_disable_runtime_pm: static void vc4_hdmi_unbind(struct device *dev, struct device *master, void *data) { - /* - * ASoC makes it a bit hard to retrieve a pointer to the - * vc4_hdmi structure. Registering the card will overwrite our - * device drvdata with a pointer to the snd_soc_card structure, - * which can then be used to retrieve whatever drvdata we want - * to associate. - * - * However, that doesn't fly in the case where we wouldn't - * register an ASoC card (because of an old DT that is missing - * the dmas properties for example), then the card isn't - * registered and the device drvdata wouldn't be set. - * - * We can deal with both cases by making sure a snd_soc_card - * pointer and a vc4_hdmi structure are pointing to the same - * memory address, so we can treat them indistinctly without any - * issue. - */ - BUILD_BUG_ON(offsetof(struct vc4_hdmi_audio, card) != 0); - BUILD_BUG_ON(offsetof(struct vc4_hdmi, audio) != 0); - pm_runtime_disable(dev); } -- 2.7.4