From: Douglas Anderson Date: Mon, 23 Apr 2018 12:49:55 +0200 Subject: drm/bridge: analogix_dp: Properly log AUX CH errors MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Git-commit: 71cef82434640fb5d219365a568c859944fedb80 Patch-mainline: v4.18-rc1 References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166 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. Cc: 征增 王 Signed-off-by: Douglas Anderson Signed-off-by: Sean Paul Signed-off-by: Thierry Escande Reviewed-by: Andrzej Hajda Signed-off-by: Enric Balletbo i Serra Tested-by: Marek Szyprowski Reviewed-by: Archit Taneja Signed-off-by: Andrzej Hajda Link: https://patchwork.freedesktop.org/patch/msgid/20180423105003.9004-20-enric.balletbo@collabora.com Acked-by: Petr Tesarik --- drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) --- 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 anal 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 anal /* 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; }