| Message ID | 1621284349-22752-1-git-send-email-sidgup@codeaurora.org |
|---|---|
| Headers | show |
| Series | remoteproc: core: Fixes for rproc cdev and add | expand |
On Mon 17 May 15:45 CDT 2021, Siddharth Gupta wrote: > When cdev_add is called after device_add has been called there is no > way for the userspace to know about the addition of a cdev as cdev_add > itself doesn't trigger a uevent notification, or for the kernel to > know about the change to devt. This results in two problems: > - mknod is never called for the cdev and hence no cdev appears on > devtmpfs. > - sysfs links to the new cdev are not established. > > The cdev needs to be added and devt assigned before device_add() is > called in order for the relevant sysfs and devtmpfs entries to be > created and the uevent to be properly populated. > Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Regards, Bjorn > Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org> > --- > drivers/remoteproc/remoteproc_core.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c > index 626a6b90f..562355a 100644 > --- a/drivers/remoteproc/remoteproc_core.c > +++ b/drivers/remoteproc/remoteproc_core.c > @@ -2316,6 +2316,11 @@ int rproc_add(struct rproc *rproc) > struct device *dev = &rproc->dev; > int ret; > > + /* add char device for this remoteproc */ > + ret = rproc_char_device_add(rproc); > + if (ret < 0) > + return ret; > + > ret = device_add(dev); > if (ret < 0) > return ret; > @@ -2329,11 +2334,6 @@ int rproc_add(struct rproc *rproc) > /* create debugfs entries */ > rproc_create_debug_dir(rproc); > > - /* add char device for this remoteproc */ > - ret = rproc_char_device_add(rproc); > - if (ret < 0) > - return ret; > - > /* if rproc is marked always-on, request it to boot */ > if (rproc->auto_boot) { > ret = rproc_trigger_auto_boot(rproc); > -- > Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project >
On Mon 17 May 15:45 CDT 2021, Siddharth Gupta wrote: > When a failure occurs in rproc_add() it returns an error, but does > not cleanup after itself. This change adds the failure path in such > cases. > > Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org> > --- > drivers/remoteproc/remoteproc_core.c | 15 ++++++++++++--- > 1 file changed, 12 insertions(+), 3 deletions(-) > > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c > index 45d09bf..6f5fa81 100644 > --- a/drivers/remoteproc/remoteproc_core.c > +++ b/drivers/remoteproc/remoteproc_core.c > @@ -2326,8 +2326,10 @@ int rproc_add(struct rproc *rproc) > return ret; > > ret = device_add(dev); > - if (ret < 0) > - return ret; > + if (ret < 0) { > + put_device(dev); > + goto rproc_remove_cdev; > + } > > dev_info(dev, "%s is available\n", rproc->name); > > @@ -2338,7 +2340,7 @@ int rproc_add(struct rproc *rproc) > if (rproc->auto_boot) { > ret = rproc_trigger_auto_boot(rproc); > if (ret < 0) > - return ret; > + goto rproc_remove_dev; > } > > /* expose to rproc_get_by_phandle users */ > @@ -2347,6 +2349,13 @@ int rproc_add(struct rproc *rproc) > mutex_unlock(&rproc_list_mutex); > > return 0; > + > +rproc_remove_dev: > + rproc_delete_debug_dir(rproc); > + device_del(dev); > +rproc_remove_cdev: > + rproc_char_device_remove(rproc); I'm confused, shouldn't this function just do cdev_del()? __unregister_chrdev() seems to do more than unroll what cdev_add() did... Apart from this, I think the patch looks good. Really nice to see you tidy this up! Regards, Bjorn > + return ret; > } > EXPORT_SYMBOL(rproc_add); > > -- > Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project >