To avoid race condition issue, we should protect the function
ipu_dmfc_init_channel() with the mutex dmfc->priv->mutex, since it
configures the register DMFC_GENERAL1 at runtime which contains
several control bits for various display channels. This matches
better with fine grained locking logic in upper layer.
Signed-off-by: Liu Ying <gnuiyl@gmail.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
struct ipu_dmfc_priv *priv = dmfc->priv;
u32 dmfc_gen1;
+ mutex_lock(&priv->mutex);
+
dmfc_gen1 = readl(priv->base + DMFC_GENERAL1);
if ((dmfc->slots * 64 * 4) / width > dmfc->data->max_fifo_lines)
writel(dmfc_gen1, priv->base + DMFC_GENERAL1);
+ mutex_unlock(&priv->mutex);
+
return 0;
}
EXPORT_SYMBOL_GPL(ipu_dmfc_init_channel);