From 9847f64ccf716bcf6f01e6e5c2a32440f8f472f4 Mon Sep 17 00:00:00 2001 From: Michael Tretter Date: Mon, 16 Mar 2020 16:26:27 +0100 Subject: [PATCH] media: allegro: fix reset if WAKEUP has not been set properly 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 Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/staging/media/allegro-dvt/allegro-core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c index ab17e850bd1fe..a56d157cb1059 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) -- 2.39.5