| Message ID | 20170816153930.15623-1-m.tretter@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 16 Aug 2017, Michael Tretter <m.tretter@pengutronix.de> wrote: > Using plain echo to set the "force" connector attribute fails with > -EINVAL, because echo appends a newline to the output. > > Strip trailing whitespace in the input before checking the value to > accept "off\n" or "off ". Please replace the strcmp() calls with sysfs_streq() instead. BR, Jani. > > Signed-off-by: Michael Tretter <m.tretter@pengutronix.de> > --- > drivers/gpu/drm/drm_debugfs.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c > index c1807d5754b2..10dd89d3f28e 100644 > --- a/drivers/gpu/drm/drm_debugfs.c > +++ b/drivers/gpu/drm/drm_debugfs.c > @@ -241,6 +241,7 @@ static ssize_t connector_write(struct file *file, const char __user *ubuf, > struct seq_file *m = file->private_data; > struct drm_connector *connector = m->private; > char buf[12]; > + int i; > > if (len > sizeof(buf) - 1) > return -EINVAL; > @@ -250,6 +251,10 @@ static ssize_t connector_write(struct file *file, const char __user *ubuf, > > buf[len] = '\0'; > > + /* strip trailing whitespace */ > + for (i = len - 1; i > 0 && isspace(buf[i]); i--) > + buf[i] = '\0'; > + > if (!strcmp(buf, "on")) > connector->force = DRM_FORCE_ON; > else if (!strcmp(buf, "digital"))
diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c index c1807d5754b2..10dd89d3f28e 100644 --- a/drivers/gpu/drm/drm_debugfs.c +++ b/drivers/gpu/drm/drm_debugfs.c @@ -241,6 +241,7 @@ static ssize_t connector_write(struct file *file, const char __user *ubuf, struct seq_file *m = file->private_data; struct drm_connector *connector = m->private; char buf[12]; + int i; if (len > sizeof(buf) - 1) return -EINVAL; @@ -250,6 +251,10 @@ static ssize_t connector_write(struct file *file, const char __user *ubuf, buf[len] = '\0'; + /* strip trailing whitespace */ + for (i = len - 1; i > 0 && isspace(buf[i]); i--) + buf[i] = '\0'; + if (!strcmp(buf, "on")) connector->force = DRM_FORCE_ON; else if (!strcmp(buf, "digital"))
Using plain echo to set the "force" connector attribute fails with -EINVAL, because echo appends a newline to the output. Strip trailing whitespace in the input before checking the value to accept "off\n" or "off ". Signed-off-by: Michael Tretter <m.tretter@pengutronix.de> --- drivers/gpu/drm/drm_debugfs.c | 5 +++++ 1 file changed, 5 insertions(+)