From mboxrd@z Thu Jan 1 00:00:00 1970 From: zain wang Subject: [PATCH] drm/bridge: analogix_dp: Don't return -EBUSY when msg->size is 0 in aux transaction Date: Mon, 13 Feb 2017 17:27:46 +0800 Message-ID: <1486978066-5351-1-git-send-email-wzz@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+glpar-linux-rockchip=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Sean Paul , Daniel Vetter , Inki Dae , David Airlie Cc: linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Heiko Stuebner , Tomeu Vizoso , linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Jingoo Han , dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, Tomasz Figa , Javier Martinez Canillas , zain wang , Mika Kahola , =?UTF-8?q?St=C3=A9phane=20Marchesin?= , Thierry Reding , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rockchip.vger.kernel.org The analogix_dp_transfer() will return -EBUSY if num_transferred is zero. But sometimes we will send a bare address packet to start the transaction, like drm_dp_i2c_xfer() show: ...... /* Send a bare address packet to start the transaction. * Zero sized messages specify an address only (bare * address) transaction. */ msg.buffer = NULL; msg.size = 0; err = drm_dp_i2c_do_msg(aux, &msg); ...... In this case, the msg->size is zero, so the num_transferred will be zero too. We can't return -EBUSY here, let's we return num_transferred if num_transferred equals msg->size. Signed-off-by: zain wang --- drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c index 303083a..5384aca 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c @@ -1162,5 +1162,5 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp, (msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_NATIVE_READ) msg->reply = DP_AUX_NATIVE_REPLY_ACK; - return num_transferred > 0 ? num_transferred : -EBUSY; + return (num_transferred == msg->size) ? num_transferred : -EBUSY; } -- 1.9.1