diff mbox series

[v2,07/18] media: allegro: fix reset if WAKEUP has not been set properly

Message ID 20200316152638.19457-8-m.tretter@pengutronix.de (mailing list archive)
State New, archived
Headers show
Series media: allegro: fixes and new features | expand

Commit Message

Michael Tretter March 16, 2020, 3:26 p.m. UTC
The Zynq UltraScale+ Devices Register Reference states that the WAKEUP
bit "should be set to 0 after the MCU sleep status bit gets back to 0."
If this is not done, the mcu is not going to sleep on reset and fail the
reset.

Set WAKEUP to 0 before triggering a reset to make sure that the reset is
successful.

Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
---
Changelog:

v1 -> v2: None
---
 drivers/staging/media/allegro-dvt/allegro-core.c | 8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
index 87592419ec84..de50405ba907 100644
--- a/drivers/staging/media/allegro-dvt/allegro-core.c
+++ b/drivers/staging/media/allegro-dvt/allegro-core.c
@@ -1990,6 +1990,14 @@  static int allegro_mcu_reset(struct allegro_dev *dev)
 {
 	int err;
 
+	/*
+	 * Ensure that the AL5_MCU_WAKEUP bit is set to 0 otherwise the mcu
+	 * does not go to sleep after the reset.
+	 */
+	err = regmap_write(dev->regmap, AL5_MCU_WAKEUP, 0);
+	if (err)
+		return err;
+
 	err = regmap_write(dev->regmap,
 			   AL5_MCU_RESET_MODE, AL5_MCU_RESET_MODE_SLEEP);
 	if (err < 0)