Linux Media Controller development
 help / color / mirror / Atom feed
From: Balakrishnan Sambath <balakrishnan.s@microchip.com>
To: <linux-media@vger.kernel.org>
Cc: <eugen.hristev@linaro.org>, <mchehab@kernel.org>,
	<hverkuil@kernel.org>, <nicolas.ferre@microchip.com>,
	<linux-kernel@vger.kernel.org>,
	"Balamanikandan Gunasundar"
	<balamanikandan.gunasundar@microchip.com>
Subject: [PATCH v2 08/15] media: microchip-isc: add gamma 1.8 and 2.4 correction curves
Date: Tue, 12 May 2026 21:13:32 +0530	[thread overview]
Message-ID: <20260512154339.210444-9-balakrishnan.s@microchip.com> (raw)
In-Reply-To: <20260512154339.210444-1-balakrishnan.s@microchip.com>

Add gamma 1.8 and 2.4 curves alongside the existing 2.2 (sRGB).
V4L2_CID_GAMMA selects preset curves: 0=2.4, 1=2.2, 2=1.8.

Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
Signed-off-by: Balakrishnan Sambath <balakrishnan.s@microchip.com>
---
 .../platform/microchip/microchip-isc-base.c   |  3 +-
 .../microchip/microchip-sama7g5-isc.c         | 54 ++++++++++++++-----
 2 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/drivers/media/platform/microchip/microchip-isc-base.c b/drivers/media/platform/microchip/microchip-isc-base.c
index 23a09ed12946..ae2a0c6ba566 100644
--- a/drivers/media/platform/microchip/microchip-isc-base.c
+++ b/drivers/media/platform/microchip/microchip-isc-base.c
@@ -1647,8 +1647,7 @@ static int isc_ctrl_init(struct isc_device *isc)
 	ctrls->brightness = 0;
 
 	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);
+	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAMMA, 0, isc->gamma_max, 1, 1);
 	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-sama7g5-isc.c b/drivers/media/platform/microchip/microchip-sama7g5-isc.c
index 04930aa0f289..8b73b625d92b 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 +460,7 @@ static int microchip_xisc_probe(struct platform_device *pdev)
 	}
 
 	isc->gamma_table = isc_sama7g5_gamma_table;
-	isc->gamma_max = 0;
+	isc->gamma_max = 2;
 
 	if (of_machine_is_compatible("microchip,sam9x7")) {
 		isc->max_width = ISC_SAM9X7_MAX_SUPPORT_WIDTH;
-- 
2.34.1


  parent reply	other threads:[~2026-05-12 15:44 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20251009155251.102472-1-balamanikandan.gunasundar@microchip.com>
2026-05-12 15:43 ` [PATCH v2 00/15] media: microchip-isc: fixes and enhancements Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 01/15] media: microchip-isc: fix SBGGR10 Bayer pattern Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 02/15] media: microchip-isc: mask WB offset and gain register fields Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 03/15] media: microchip-isc: fix race condition on stream stop Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 04/15] media: microchip-isc: fix PM runtime leak in AWB work handler Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 05/15] media: microchip-isc: add driver documentation Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 06/15] media: microchip-isc: set SAM9X7 maximum resolution to 2560x1920 Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 07/15] media: microchip-isc: configure DPC and pipeline for SAMA7G5 Balakrishnan Sambath
2026-05-12 15:43   ` Balakrishnan Sambath [this message]
2026-05-12 15:43   ` [PATCH v2 09/15] media: microchip-isc: add SAMA7G5 hue and saturation controls Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 10/15] media: microchip-isc: expose color correction matrix as V4L2 controls Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 11/15] media: microchip-isc: add per-channel gamma LUT controls Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 12/15] media: microchip-isc: reset pipeline state on kernel AWB enable Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 13/15] media: microchip-isc: use weighted averages for Grey World AWB Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 14/15] media: microchip-isc: smooth AWB gains with EMA filter Balakrishnan Sambath
2026-05-12 15:43   ` [PATCH v2 15/15] 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=20260512154339.210444-9-balakrishnan.s@microchip.com \
    --to=balakrishnan.s@microchip.com \
    --cc=balamanikandan.gunasundar@microchip.com \
    --cc=eugen.hristev@linaro.org \
    --cc=hverkuil@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=nicolas.ferre@microchip.com \
    /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