[PATCH v5 46/69] drm/vc4: hdmi: Move audio structure offset checks
Maxime Ripard
maxime at cerno.tech
Mon Jul 11 17:39:16 UTC 2022
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 <tzimmermann at suse.de>
Signed-off-by: Maxime Ripard <maxime at 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 514253fa26fe..5676fc499c16 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -2077,6 +2077,26 @@ 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");
@@ -3083,26 +3103,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
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);
}
--
2.36.1
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