From: Francesco Dolcini Date: Tue, 28 Nov 2023 19:49:35 +0000 (+0100) Subject: platform/surface: aggregator: fix recv_buf() return value X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c8820c92caf0770bec976b01fa9e82bb993c5865;p=linux.git platform/surface: aggregator: fix recv_buf() return value Serdev recv_buf() callback is supposed to return the amount of bytes consumed, therefore an int in between 0 and count. Do not return negative number in case of issue, when ssam_controller_receive_buf() returns ESHUTDOWN just returns 0, e.g. no bytes consumed, this keep the exact same behavior as it was before. This fixes a potential WARN in serdev-ttyport.c:ttyport_receive_buf(). Fixes: c167b9c7e3d6 ("platform/surface: Add Surface Aggregator subsystem") Cc: stable@vger.kernel.org Signed-off-by: Francesco Dolcini Reviewed-by: Maximilian Luz Link: https://lore.kernel.org/r/20231128194935.11350-1-francesco@dolcini.it Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- diff --git a/drivers/platform/surface/aggregator/core.c b/drivers/platform/surface/aggregator/core.c index 1a6373dea109c..6152be38398c4 100644 --- a/drivers/platform/surface/aggregator/core.c +++ b/drivers/platform/surface/aggregator/core.c @@ -231,9 +231,12 @@ static int ssam_receive_buf(struct serdev_device *dev, const unsigned char *buf, size_t n) { struct ssam_controller *ctrl; + int ret; ctrl = serdev_device_get_drvdata(dev); - return ssam_controller_receive_buf(ctrl, buf, n); + ret = ssam_controller_receive_buf(ctrl, buf, n); + + return ret < 0 ? 0 : ret; } static void ssam_write_wakeup(struct serdev_device *dev)