The Iridix Tonemap engine, if not bypassed, applies a digital gain
in order to compensate under-exposed images.

This however breaks the exposure and gain regulation performed on the
sensor.

If the Iridix Tonemap has to be used, it need to be supported in the
ISP uAPI and properly configured by userspace.

As the driver doesn't support it at the moment, bypass it by default.

Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
---
 drivers/media/platform/arm/mali-c55/mali-c55-params.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-params.c b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
index 773e5b6a2b7e..b9fc904a3844 100644
--- a/drivers/media/platform/arm/mali-c55/mali-c55-params.c
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
@@ -825,6 +825,11 @@ void mali_c55_params_init_isp_config(struct mali_c55 *mali_c55,
 	/* Disable the temper module's DMA read/write */
 	mali_c55_ctx_write(mali_c55, MALI_C55_REG_TEMPER_DMA_IO, 0x0);
 
+	/* Disable IRIDIX module. */
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_BYPASS_3,
+				 MALI_C55_REG_BYPASS_3_IRIDIX,
+				 MALI_C55_REG_BYPASS_3_IRIDIX);
+
 	/* Bypass the colour noise reduction  */
 	mali_c55_ctx_write(mali_c55, MALI_C55_REG_BYPASS_4,
 			   MALI_C55_REG_BYPASS_4_CNR);

-- 
2.53.0

2026. 03. 13. 15:54 keltezéssel, Jacopo Mondi írta:
> The Iridix Tonemap engine, if not bypassed, applies a digital gain
> in order to compensate under-exposed images.
> 
> This however breaks the exposure and gain regulation performed on the
> sensor.
> 
> If the Iridix Tonemap has to be used, it need to be supported in the
> ISP uAPI and properly configured by userspace.
> 
> As the driver doesn't support it at the moment, bypass it by default.
> 
> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> ---

Reviewed-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>


>   drivers/media/platform/arm/mali-c55/mali-c55-params.c | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-params.c b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> index 773e5b6a2b7e..b9fc904a3844 100644
> --- a/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> @@ -825,6 +825,11 @@ void mali_c55_params_init_isp_config(struct mali_c55 *mali_c55,
>   	/* Disable the temper module's DMA read/write */
>   	mali_c55_ctx_write(mali_c55, MALI_C55_REG_TEMPER_DMA_IO, 0x0);
>   
> +	/* Disable IRIDIX module. */
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_BYPASS_3,
> +				 MALI_C55_REG_BYPASS_3_IRIDIX,
> +				 MALI_C55_REG_BYPASS_3_IRIDIX);
> +
>   	/* Bypass the colour noise reduction  */
>   	mali_c55_ctx_write(mali_c55, MALI_C55_REG_BYPASS_4,
>   			   MALI_C55_REG_BYPASS_4_CNR);
> 

Hi

On 13/03/2026 14:54, Jacopo Mondi wrote:
> The Iridix Tonemap engine, if not bypassed, applies a digital gain
> in order to compensate under-exposed images.
> 
> This however breaks the exposure and gain regulation performed on the
> sensor.
> 
> If the Iridix Tonemap has to be used, it need to be supported in the
> ISP uAPI and properly configured by userspace.
> 
> As the driver doesn't support it at the moment, bypass it by default.
> 
> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>

Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>

> ---
>   drivers/media/platform/arm/mali-c55/mali-c55-params.c | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-params.c b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> index 773e5b6a2b7e..b9fc904a3844 100644
> --- a/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> @@ -825,6 +825,11 @@ void mali_c55_params_init_isp_config(struct mali_c55 *mali_c55,
>   	/* Disable the temper module's DMA read/write */
>   	mali_c55_ctx_write(mali_c55, MALI_C55_REG_TEMPER_DMA_IO, 0x0);
>   
> +	/* Disable IRIDIX module. */
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_BYPASS_3,
> +				 MALI_C55_REG_BYPASS_3_IRIDIX,
> +				 MALI_C55_REG_BYPASS_3_IRIDIX);
> +
>   	/* Bypass the colour noise reduction  */
>   	mali_c55_ctx_write(mali_c55, MALI_C55_REG_BYPASS_4,
>   			   MALI_C55_REG_BYPASS_4_CNR);
>