From: Balakrishnan Sambath <balakrishnan.s@microchip.com>
To: Eugen Hristev <ehristev@kernel.org>,
Mauro Carvalho Chehab <mchehab@kernel.org>,
Hans Verkuil <hverkuil@kernel.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
Kieran Bingham <kieran.bingham@ideasonboard.com>,
Sakari Ailus <sakari.ailus@linux.intel.com>,
Balamanikandan Gunasundar
<balamanikandan.gunasundar@microchip.com>,
<stable@vger.kernel.org>, <linux-media@vger.kernel.org>,
<linux-kernel@vger.kernel.org>,
"Balakrishnan Sambath" <balakrishnan.s@microchip.com>
Subject: [PATCH v5 08/12] media: microchip-isc: add gamma 1.8 and 2.4 correction curves
Date: Wed, 27 May 2026 16:37:24 +0530 [thread overview]
Message-ID: <20260527-microchip-isc-fixes-v5-8-b0ec1bb954be@microchip.com> (raw)
In-Reply-To: <20260527-microchip-isc-fixes-v5-0-b0ec1bb954be@microchip.com>
Display profiles for older macOS content (gamma 1.8) and HDR
pipelines (gamma 2.4) need curves not covered by the existing sRGB
2.2 default. Add the two extra curves to the SAMA7G5 table so
userspace can pick a curve matching the target display profile.
The two SoCs put gamma 1/2.2 at different indices in their tables
(SAMA5D2 at index 2, SAMA7G5 at index 1), so introduce a
gamma_default field on struct isc_device and let each platform set
it. The SAMA5D2 default of index 2 matches the historical behaviour.
Co-developed-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
Signed-off-by: Balakrishnan Sambath <balakrishnan.s@microchip.com>
---
.../media/platform/microchip/microchip-isc-base.c | 2 +-
drivers/media/platform/microchip/microchip-isc.h | 1 +
.../platform/microchip/microchip-sama5d2-isc.c | 2 +
.../platform/microchip/microchip-sama7g5-isc.c | 56 ++++++++++++++++------
4 files changed, 46 insertions(+), 15 deletions(-)
diff --git a/drivers/media/platform/microchip/microchip-isc-base.c b/drivers/media/platform/microchip/microchip-isc-base.c
index ff920019fe37..04187127070d 100644
--- a/drivers/media/platform/microchip/microchip-isc-base.c
+++ b/drivers/media/platform/microchip/microchip-isc-base.c
@@ -1648,7 +1648,7 @@ static int isc_ctrl_init(struct isc_device *isc)
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_BRIGHTNESS, -1024, 1023, 1, 0);
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAMMA, 0, isc->gamma_max, 1,
- isc->gamma_max);
+ isc->gamma_default);
isc->awb_ctrl = v4l2_ctrl_new_std(hdl, &isc_awb_ops,
V4L2_CID_AUTO_WHITE_BALANCE,
0, 1, 1, 1);
diff --git a/drivers/media/platform/microchip/microchip-isc.h b/drivers/media/platform/microchip/microchip-isc.h
index a943b072f6be..2282ef7dd596 100644
--- a/drivers/media/platform/microchip/microchip-isc.h
+++ b/drivers/media/platform/microchip/microchip-isc.h
@@ -342,6 +342,7 @@ struct isc_device {
/* pointer to the defined gamma table */
const u32 (*gamma_table)[GAMMA_ENTRIES];
u32 gamma_max;
+ u32 gamma_default;
u32 max_width;
u32 max_height;
diff --git a/drivers/media/platform/microchip/microchip-sama5d2-isc.c b/drivers/media/platform/microchip/microchip-sama5d2-isc.c
index 71609a93358a..9fa8413c74c7 100644
--- a/drivers/media/platform/microchip/microchip-sama5d2-isc.c
+++ b/drivers/media/platform/microchip/microchip-sama5d2-isc.c
@@ -442,6 +442,8 @@ static int microchip_isc_probe(struct platform_device *pdev)
isc->gamma_table = isc_sama5d2_gamma_table;
isc->gamma_max = 2;
+ /* Index 2 in the SAMA5D2 table is gamma 1/2.2 (sRGB). */
+ isc->gamma_default = 2;
isc->max_width = ISC_SAMA5D2_MAX_SUPPORT_WIDTH;
isc->max_height = ISC_SAMA5D2_MAX_SUPPORT_HEIGHT;
diff --git a/drivers/media/platform/microchip/microchip-sama7g5-isc.c b/drivers/media/platform/microchip/microchip-sama7g5-isc.c
index daa3978a89bd..06aa801b88f9 100644
--- a/drivers/media/platform/microchip/microchip-sama7g5-isc.c
+++ b/drivers/media/platform/microchip/microchip-sama7g5-isc.c
@@ -320,21 +320,47 @@ static void isc_sama7g5_adapt_pipeline(struct isc_device *isc)
isc->try_config.bits_pipeline &= ISC_SAMA7G5_PIPELINE;
}
-/* Gamma table with gamma 1/2.2 */
+/* Gamma tables with gamma values 0.42, 0.45(Default), 0.56 */
static const u32 isc_sama7g5_gamma_table[][GAMMA_ENTRIES] = {
- /* index 0 --> gamma bipartite */
+ /* index 0 --> gamma bipartite 1/2.4(=0.42) */
{
- 0x980, 0x4c0320, 0x650260, 0x7801e0, 0x8701a0, 0x940180,
- 0xa00160, 0xab0120, 0xb40120, 0xbd0120, 0xc60100, 0xce0100,
- 0xd600e0, 0xdd00e0, 0xe400e0, 0xeb00c0, 0xf100c0, 0xf700c0,
- 0xfd00c0, 0x10300a0, 0x10800c0, 0x10e00a0, 0x11300a0, 0x11800a0,
- 0x11d00a0, 0x12200a0, 0x12700a0, 0x12c0080, 0x13000a0, 0x1350080,
- 0x13900a0, 0x13e0080, 0x1420076, 0x17d0062, 0x1ae0054, 0x1d8004a,
- 0x1fd0044, 0x21f003e, 0x23e003a, 0x25b0036, 0x2760032, 0x28f0030,
- 0x2a7002e, 0x2be002c, 0x2d4002c, 0x2ea0028, 0x2fe0028, 0x3120026,
- 0x3250024, 0x3370024, 0x3490022, 0x35a0022, 0x36b0020, 0x37b0020,
- 0x38b0020, 0x39b001e, 0x3aa001e, 0x3b9001c, 0x3c7001c, 0x3d5001c,
- 0x3e3001c, 0x3f1001c, 0x3ff001a, 0x40c001a },
+ 0x940, 0x4b0310, 0x630250, 0x7601d0, 0x840190, 0x910170,
+ 0x9d0150, 0xa80110, 0xb10110, 0xba0110, 0xc300f0, 0xcb00f0,
+ 0xd300e0, 0xda00e0, 0xe100c0, 0xe800c0, 0xee00c0, 0xf400c0,
+ 0xfa00a0, 0x10000a0, 0x10500a0, 0x10b00a0, 0x11000a0, 0x11500a0,
+ 0x11a0080, 0x11f0080, 0x1240080, 0x1290080, 0x12e0080, 0x1330070,
+ 0x1380070, 0x13c0070, 0x1410070, 0x17a0060, 0x1aa0052, 0x1d40046,
+ 0x1f90042, 0x21b003c, 0x23a0038, 0x2570034, 0x2720030, 0x28b002e,
+ 0x2a3002c, 0x2ba002a, 0x2d0002a, 0x2e60028, 0x2fa0026, 0x30e0026,
+ 0x3210024, 0x3330022, 0x3450022, 0x3560020, 0x3670020, 0x3770020,
+ 0x387001e, 0x396001e, 0x3a5001c, 0x3b3001c, 0x3c1001c, 0x3cf001a,
+ 0x3dd001a, 0x3eb0018, 0x3f90018, 0x4070016 },
+ /* index 1 --> gamma bipartite 1/2.2(=0.45) */
+ {
+ 0x980, 0x4c0320, 0x650260, 0x7801e0, 0x8701a0, 0x940180,
+ 0xa00160, 0xab0120, 0xb40120, 0xbd0120, 0xc60100, 0xce0100,
+ 0xd600e0, 0xdd00e0, 0xe400e0, 0xeb00c0, 0xf100c0, 0xf700c0,
+ 0xfd00c0, 0x10300a0, 0x10800c0, 0x10e00a0, 0x11300a0, 0x11800a0,
+ 0x11d00a0, 0x12200a0, 0x12700a0, 0x12c0080, 0x13000a0, 0x1350080,
+ 0x13900a0, 0x13e0080, 0x1420076, 0x17d0062, 0x1ae0054, 0x1d8004a,
+ 0x1fd0044, 0x21f003e, 0x23e003a, 0x25b0036, 0x2760032, 0x28f0030,
+ 0x2a7002e, 0x2be002c, 0x2d4002c, 0x2ea0028, 0x2fe0028, 0x3120026,
+ 0x3250024, 0x3370024, 0x3490022, 0x35a0022, 0x36b0020, 0x37b0020,
+ 0x38b0020, 0x39b001e, 0x3aa001e, 0x3b9001c, 0x3c7001c, 0x3d5001c,
+ 0x3e3001c, 0x3f1001c, 0x3ff001a, 0x40c001a },
+ /* index 2 --> gamma bipartite 1/1.8(=0.56) */
+ {
+ 0xa62, 0x4f0350, 0x680280, 0x7e0200, 0x8d01c0, 0x9a01a0,
+ 0xa50180, 0xb00140, 0xb90140, 0xc20120, 0xcb0120, 0xd30100,
+ 0xdb0100, 0xe300e0, 0xea00e0, 0xf100e0, 0xf700c0, 0xfd00c0,
+ 0x10300c0, 0x10900a0, 0x10e00a0, 0x11400a0, 0x11900a0, 0x11e00a0,
+ 0x12300a0, 0x12800a0, 0x12d0080, 0x1320080, 0x1370080, 0x13c0080,
+ 0x1410080, 0x1460080, 0x14a0070, 0x1830060, 0x1b40052, 0x1df0048,
+ 0x2040042, 0x2250040, 0x2440038, 0x2600036, 0x27b0032, 0x2940030,
+ 0x2ac002e, 0x2c4002c, 0x2da002a, 0x2f0002a, 0x3050028, 0x3190026,
+ 0x32c0026, 0x33e0024, 0x3500024, 0x3610022, 0x3720020, 0x3820020,
+ 0x3920020, 0x3a2001e, 0x3b1001e, 0x3c0001c, 0x3ce001c, 0x3dc001c,
+ 0x3ea001a, 0x3f8001a, 0x4060018, 0x4130018 },
};
static int xisc_parse_dt(struct device *dev, struct isc_device *isc)
@@ -434,7 +460,9 @@ static int microchip_xisc_probe(struct platform_device *pdev)
}
isc->gamma_table = isc_sama7g5_gamma_table;
- isc->gamma_max = 0;
+ isc->gamma_max = 2;
+ /* Index 1 in the SAMA7G5 table is gamma 1/2.2 (sRGB). */
+ isc->gamma_default = 1;
if (of_machine_is_compatible("microchip,sam9x7")) {
isc->max_width = ISC_SAM9X7_MAX_SUPPORT_WIDTH;
--
2.34.1
next prev parent reply other threads:[~2026-05-27 11:07 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-27 11:07 [PATCH v5 00/12] media: microchip-isc: fixes and enhancements Balakrishnan Sambath
2026-05-27 11:07 ` [PATCH v5 01/12] media: microchip-isc: fix SBGGR10 Bayer pattern Balakrishnan Sambath
2026-05-27 17:03 ` Eugen Hristev
2026-05-27 11:07 ` [PATCH v5 02/12] media: microchip-isc: fix WB offset and gain register field masking Balakrishnan Sambath
2026-05-27 11:07 ` [PATCH v5 03/12] media: microchip-isc: fix race condition on stream stop Balakrishnan Sambath
2026-05-27 11:07 ` [PATCH v5 04/12] media: microchip-isc: fix PM runtime leak in AWB work handler Balakrishnan Sambath
2026-05-27 11:07 ` [PATCH v5 05/12] media: microchip-isc: add driver documentation Balakrishnan Sambath
2026-05-27 11:07 ` [PATCH v5 06/12] media: microchip-isc: set SAM9X7 maximum resolution to 2560x1920 Balakrishnan Sambath
2026-05-27 11:07 ` [PATCH v5 07/12] media: microchip-isc: configure DPC and pipeline for SAMA7G5 Balakrishnan Sambath
2026-05-27 11:07 ` Balakrishnan Sambath [this message]
2026-05-27 11:07 ` [PATCH v5 09/12] media: microchip-isc: add SAMA7G5 hue and saturation controls Balakrishnan Sambath
2026-05-29 15:20 ` Eugen Hristev
2026-05-29 16:35 ` Balakrishnan.S
2026-05-27 11:07 ` [PATCH v5 10/12] media: microchip-isc: use weighted averages for Grey World AWB Balakrishnan Sambath
2026-05-27 11:07 ` [PATCH v5 11/12] media: microchip-isc: smooth AWB gains with EMA filter Balakrishnan Sambath
2026-05-28 20:20 ` Eugen Hristev
2026-05-29 6:34 ` Balakrishnan.S
2026-05-27 11:07 ` [PATCH v5 12/12] media: microchip-isc: scale DPC black level to sensor bit depth Balakrishnan Sambath
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260527-microchip-isc-fixes-v5-8-b0ec1bb954be@microchip.com \
--to=balakrishnan.s@microchip.com \
--cc=balamanikandan.gunasundar@microchip.com \
--cc=ehristev@kernel.org \
--cc=hverkuil@kernel.org \
--cc=kieran.bingham@ideasonboard.com \
--cc=laurent.pinchart@ideasonboard.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=mchehab@kernel.org \
--cc=sakari.ailus@linux.intel.com \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®