@@ -125,4 +125,15 @@ config OMAP2_DSS_MIN_FCK_PER_PCK
Max FCK is 173MHz, so this doesn't work if your PCK
is very high.
+config OMAP2_DSS_SLEEP_BEFORE_RESET
+ bool "Sleep 50ms before DSS reset"
+ default y
+ help
+ For some unknown reason we may get SYNC_LOST errors from the display
+ subsystem at initialization time if we don't sleep before resetting
+ the DSS. See the source (dss.c) for more comments.
+
+ However, 50ms is quite long time to sleep, and with some
+ configurations the SYNC_LOST may never happen, so the sleep can
+ be disabled here.
endif
@@ -659,13 +659,18 @@ static int dss_init(void)
* the kernel resets it */
omap_writel(omap_readl(0x48050440) & ~0x3, 0x48050440);
+#ifdef CONFIG_OMAP2_DSS_SLEEP_BEFORE_RESET
/* We need to wait here a bit, otherwise we sometimes start to
* get synclost errors, and after that only power cycle will
* restore DSS functionality. I have no idea why this happens.
* And we have to wait _before_ resetting the DSS, but after
* enabling clocks.
+ *
+ * This bug was at least present on OMAP3430. It's unknown
+ * if it happens on OMAP2 or OMAP3630.
*/
msleep(50);
+#endif
_omap_dss_reset();