[PATCH v5 25/36] drm/bridge: analogix_dp: Properly log AUX CH errors

[Archit Taneja]

On Saturday 10 March 2018 03:53 AM, Enric Balletbo i Serra wrote:
> From: Douglas Anderson <dianders at chromium.org>
> 
> The code in analogix_dp_transfer() that was supposed to print out:
>    AUX CH error happened
> 
> Was actually dead code. That's because the previous check (whether
> the interrupt status indicated any errors) would have hit for all
> errors anyway.
> 
> Let's combine the two error checks so we can actually see AUX CH
> errors.  We'll also downgrade the message to a warning since some of
> these types of errors might be expected for some displays.  If this
> gets too noisy we can downgrade again to debug.

Reviewed-by: Archit Taneja <architt at codeaurora.org>

Thanks,
Archit

> 
> Cc: 征增 王 <wzz at rock-chips.com>
> Signed-off-by: Douglas Anderson <dianders at chromium.org>
> Signed-off-by: Sean Paul <seanpaul at chromium.org>
> Signed-off-by: Thierry Escande <thierry.escande at collabora.com>
> Reviewed-by: Andrzej Hajda <a.hajda at samsung.com>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo at collabora.com>
> Tested-by: Marek Szyprowski <m.szyprowski at samsung.com>
> ---
> 
>   drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 13 +++++--------
>   1 file changed, 5 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> index 4eae206ec31b..58e8a28e99aa 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> @@ -1105,6 +1105,7 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
>   			     struct drm_dp_aux_msg *msg)
>   {
>   	u32 reg;
> +	u32 status_reg;
>   	u8 *buffer = msg->buffer;
>   	unsigned int i;
>   	int num_transferred = 0;
> @@ -1193,16 +1194,12 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
>   
>   	/* Clear interrupt source for AUX CH access error */
>   	reg = readl(dp->reg_base + ANALOGIX_DP_INT_STA);
> -	if (reg & AUX_ERR) {
> +	status_reg = readl(dp->reg_base + ANALOGIX_DP_AUX_CH_STA);
> +	if ((reg & AUX_ERR) || (status_reg & AUX_STATUS_MASK)) {
>   		writel(AUX_ERR, dp->reg_base + ANALOGIX_DP_INT_STA);
> -		goto aux_error;
> -	}
>   
> -	/* Check AUX CH error access status */
> -	reg = readl(dp->reg_base + ANALOGIX_DP_AUX_CH_STA);
> -	if ((reg & AUX_STATUS_MASK)) {
> -		dev_err(dp->dev, "AUX CH error happened: %d\n\n",
> -			reg & AUX_STATUS_MASK);
> +		dev_warn(dp->dev, "AUX CH error happened: %#x (%d)\n",
> +			 status_reg & AUX_STATUS_MASK, !!(reg & AUX_ERR));
>   		goto aux_error;
>   	}
>   
>