[PATCH v6 03/10] drm/bridge: it6505: add AUX operation for HDCP KSV list read

[Dmitry Baryshkov]

On Wed, Oct 16, 2024 at 03:54:15PM +0800, Hermes Wu via B4 Relay wrote:
> From: Hermes Wu <Hermes.wu at ite.com.tw>
> 
> HDCP KSV list readback can choose to use AUX FIFO or
> general data register.
> For some DisplayPort devices, the KSV list must be read
> in 5 byte boundaries.
> The original AUX read command does not support these devices.
> 
> The AUX command operation control register "REG_AUX_CMD_REQ" uses b[3:0]
> as AUX operacion control, and b[7:4] are status bits and read only.
> To change KSV read operation uses "CMD_AUX_NATIVE_READ" from using
> the data registers to using AUX FIFO.
> The extended command "CMD_AUX_GET_KSV_LIST" is added as
> "CMD_AUX_NATIVE_READ" with the 0x10 flag which selects AUX FIFO mode.
> 
> Signed-off-by: Hermes Wu <Hermes.wu at ite.com.tw>
> ---
>  drivers/gpu/drm/bridge/ite-it6505.c | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)
> 

> @@ -996,7 +1001,7 @@ static ssize_t it6505_aux_operation(struct it6505 *it6505,
>  				  size);
>  
>  	/* Aux Fire */
> -	it6505_write(it6505, REG_AUX_CMD_REQ, cmd);
> +	it6505_write(it6505, REG_AUX_CMD_REQ, FIELD_GET(M_AUX_REQ_CMD, cmd));

This needs #include <linux/bitfield.h>

Other than that

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>


>  
>  	ret = it6505_aux_wait(it6505);
>  	if (ret < 0)

-- 
With best wishes
Dmitry