From 36230cb5668c2633bee4ec87b58983eac3a5cb4c Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Wed, 27 Apr 2016 22:43:45 +0300 Subject: [PATCH] drm/dp: Allow signals to interrupt drm_aux-dev reads/writes MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Let's be nice and interrupt the dpcd aux-dev reads/writes when there's a signal pending. Much nicer if the user can hit ^C instead of having to sit around waiting for the read/write to finish. time dd if=/dev/drm_dp_aux0 bs=$((1024*1024)) ^C before: real 0m34.681s user 0m0.003s sys 0m6.880s after: real 0m0.222s user 0m0.006s sys 0m0.057s Cc: Rafael Antognolli Signed-off-by: Ville Syrjälä Reviewed-by: Jani Nikula Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1461786225-7790-1-git-send-email-ville.syrjala@linux.intel.com --- drivers/gpu/drm/drm_dp_aux_dev.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/gpu/drm/drm_dp_aux_dev.c b/drivers/gpu/drm/drm_dp_aux_dev.c index f73b38b33a8e..3334baacf43d 100644 --- a/drivers/gpu/drm/drm_dp_aux_dev.c +++ b/drivers/gpu/drm/drm_dp_aux_dev.c @@ -159,6 +159,12 @@ static ssize_t auxdev_read(struct file *file, char __user *buf, size_t count, uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES]; ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf)); + if (signal_pending(current)) { + res = num_bytes_processed ? + num_bytes_processed : -ERESTARTSYS; + goto out; + } + res = drm_dp_dpcd_read(aux_dev->aux, *offset, localbuf, todo); if (res <= 0) { res = num_bytes_processed ? num_bytes_processed : res; @@ -202,6 +208,12 @@ static ssize_t auxdev_write(struct file *file, const char __user *buf, uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES]; ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf)); + if (signal_pending(current)) { + res = num_bytes_processed ? + num_bytes_processed : -ERESTARTSYS; + goto out; + } + if (__copy_from_user(localbuf, buf + num_bytes_processed, todo)) { res = num_bytes_processed ? -- 2.20.1