From bfced6d1ec917436dd02e180bf52d71cd4a335a7 Mon Sep 17 00:00:00 2001 From: Chiranjeevi Rapolu Date: Fri, 28 Jul 2017 19:21:03 -0400 Subject: [PATCH] media: ov13858: Increase digital gain granularity, range Previously, possible digital gains were just 1x, 2x and 4x. These coarse gains were not sufficient in fine-tuning the image capture. Now, digital gain range is [0, 16x] with each step 1/1024, default 1x. This is achieved through OV13858 MWB R/G/B gain controls. Signed-off-by: Chiranjeevi Rapolu Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/ov13858.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/drivers/media/i2c/ov13858.c b/drivers/media/i2c/ov13858.c index 867845bd4314..45c0e96a4cba 100644 --- a/drivers/media/i2c/ov13858.c +++ b/drivers/media/i2c/ov13858.c @@ -77,13 +77,13 @@ #define OV13858_ANA_GAIN_DEFAULT 0x80 /* Digital gain control */ -#define OV13858_REG_DIGITAL_GAIN 0x350a -#define OV13858_DGTL_GAIN_MASK 0xf3 -#define OV13858_DGTL_GAIN_SHIFT 2 -#define OV13858_DGTL_GAIN_MIN 1 -#define OV13858_DGTL_GAIN_MAX 4 -#define OV13858_DGTL_GAIN_STEP 1 -#define OV13858_DGTL_GAIN_DEFAULT 1 +#define OV13858_REG_B_MWB_GAIN 0x5100 +#define OV13858_REG_G_MWB_GAIN 0x5102 +#define OV13858_REG_R_MWB_GAIN 0x5104 +#define OV13858_DGTL_GAIN_MIN 0 +#define OV13858_DGTL_GAIN_MAX 16384 /* Max = 16 X */ +#define OV13858_DGTL_GAIN_DEFAULT 1024 /* Default gain = 1 X */ +#define OV13858_DGTL_GAIN_STEP 1 /* Each step = 1/1024 */ /* Test Pattern Control */ #define OV13858_REG_TEST_PATTERN 0x4503 @@ -1162,21 +1162,21 @@ static int ov13858_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) static int ov13858_update_digital_gain(struct ov13858 *ov13858, u32 d_gain) { int ret; - u32 val; - if (d_gain == 3) - return -EINVAL; - - ret = ov13858_read_reg(ov13858, OV13858_REG_DIGITAL_GAIN, - OV13858_REG_VALUE_08BIT, &val); + ret = ov13858_write_reg(ov13858, OV13858_REG_B_MWB_GAIN, + OV13858_REG_VALUE_16BIT, d_gain); if (ret) return ret; - val &= OV13858_DGTL_GAIN_MASK; - val |= (d_gain - 1) << OV13858_DGTL_GAIN_SHIFT; + ret = ov13858_write_reg(ov13858, OV13858_REG_G_MWB_GAIN, + OV13858_REG_VALUE_16BIT, d_gain); + if (ret) + return ret; - return ov13858_write_reg(ov13858, OV13858_REG_DIGITAL_GAIN, - OV13858_REG_VALUE_08BIT, val); + ret = ov13858_write_reg(ov13858, OV13858_REG_R_MWB_GAIN, + OV13858_REG_VALUE_16BIT, d_gain); + + return ret; } static int ov13858_enable_test_pattern(struct ov13858 *ov13858, u32 pattern)