From 9e0bf8393d0602cc7fda749b77cf8ec7f81249cb Mon Sep 17 00:00:00 2001 From: Jacopo Mondi Date: Wed, 16 Jun 2021 14:46:08 +0200 Subject: media: i2c: max9271: Introduce wake_up() function The MAX9271 chip manual prescribes a delay of 5 milliseconds after the chip exits from low power state. Add a new function to the max9271 library driver that wakes up the chip with a dummy i2c transaction and implements the correct delay of 5 milliseconds after the chip exits from low power state. Use the newly introduced function in the rdacm20 and rdacm21 camera drivers. The former was not respecting the required delay while the latter was waiting for a too-short timeout. Signed-off-by: Jacopo Mondi Reviewed-by: Kieran Bingham Reviewed-by: Laurent Pinchart Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/max9271.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'drivers/media/i2c/max9271.h') diff --git a/drivers/media/i2c/max9271.h b/drivers/media/i2c/max9271.h index d78fb21441e9..dc5e4e70ba6f 100644 --- a/drivers/media/i2c/max9271.h +++ b/drivers/media/i2c/max9271.h @@ -85,6 +85,15 @@ struct max9271_device { struct i2c_client *client; }; +/** + * max9271_wake_up() - Wake up the serializer by issuing an i2c transaction + * @dev: The max9271 device + * + * This function shall be called before any other interaction with the + * serializer. + */ +void max9271_wake_up(struct max9271_device *dev); + /** * max9271_set_serial_link() - Enable/disable serial link * @dev: The max9271 device -- cgit