1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (c) 2019 Microchip Technology Inc. and its subsidiaries
5 * Author: Eugen Hristev <eugen.hristev@microchip.com>
8 #ifndef __LINUX_ATMEL_ISC_MEDIA_H__
9 #define __LINUX_ATMEL_ISC_MEDIA_H__
12 * There are 8 controls available:
13 * 4 gain controls, sliders, for each of the BAYER components: R, B, GR, GB.
14 * These gains are multipliers for each component, in format unsigned 0:4:9 with
15 * a default value of 512 (1.0 multiplier).
16 * 4 offset controls, sliders, for each of the BAYER components: R, B, GR, GB.
17 * These offsets are added/substracted from each component, in format signed
18 * 1:12:0 with a default value of 0 (+/- 0)
20 * To expose this to userspace, added 8 custom controls, in an auto cluster.
22 * To summarize the functionality:
23 * The auto cluster switch is the auto white balance control, and it works
25 * AWB == 1: autowhitebalance is on, the do_white_balance button is inactive,
26 * the gains/offsets are inactive, but volatile and readable.
27 * Thus, the results of the whitebalance algorithm are available to userspace to
29 * AWB == 0: autowhitebalance is off, cluster is in manual mode, user can
30 * configure the gain/offsets directly.
31 * More than that, if the do_white_balance button is
32 * pressed, the driver will perform one-time-adjustment, (preferably with color
33 * checker card) and the userspace can read again the new values.
35 * With this feature, the userspace can save the coefficients and reinstall them
36 * for example after reboot or reprobing the driver.
39 enum atmel_isc_ctrl_id {
40 /* Red component gain control */
41 ISC_CID_R_GAIN = (V4L2_CID_USER_ATMEL_ISC_BASE + 0),
42 /* Blue component gain control */
44 /* Green Red component gain control */
46 /* Green Blue gain control */
48 /* Red component offset control */
50 /* Blue component offset control */
52 /* Green Red component offset control */
54 /* Green Blue component offset control */