| Message ID | 1440975352-28528-6-git-send-email-sjg@chromium.org |
|---|---|
| State | Accepted |
| Delegated to: | Simon Glass |
| Headers | show |
On 30 August 2015 at 16:55, Simon Glass <sjg@chromium.org> wrote: > When a uclass definition is missing, no drivers in that uclass can operate. > This can happen if a board has a strange collection of options (e.g. the > driver is enabled but the uclass is not). > > Unfortunately this is very confusing at present. Starting up driver model > results in a -ENOENT error, which is pretty generic. Quite a big of digging > is needed to get to the root cause. > > To help with this, change the error to a very strange one with no other > users in U-Boot. Also add a debug message. > > Signed-off-by: Simon Glass <sjg@chromium.org> > --- > > Changes in v5: None > Changes in v4: None > Changes in v3: None > Changes in v2: None > > drivers/core/device.c | 4 +++- > drivers/core/uclass.c | 7 ++++++- > 2 files changed, 9 insertions(+), 2 deletions(-) Applied to u-boot-rockchip.
diff --git a/drivers/core/device.c b/drivers/core/device.c index a6cd936..0ccd443 100644 --- a/drivers/core/device.c +++ b/drivers/core/device.c @@ -39,8 +39,10 @@ int device_bind(struct udevice *parent, const struct driver *drv, return -EINVAL; ret = uclass_get(drv->id, &uc); - if (ret) + if (ret) { + debug("Missing uclass for driver %s\n", drv->name); return ret; + } dev = calloc(1, sizeof(struct udevice)); if (!dev) diff --git a/drivers/core/uclass.c b/drivers/core/uclass.c index f63ff59..e800c28 100644 --- a/drivers/core/uclass.c +++ b/drivers/core/uclass.c @@ -58,7 +58,12 @@ static int uclass_add(enum uclass_id id, struct uclass **ucp) if (!uc_drv) { debug("Cannot find uclass for id %d: please add the UCLASS_DRIVER() declaration for this UCLASS_... id\n", id); - return -ENOENT; + /* + * Use a strange error to make this case easier to find. When + * a uclass is not available it can prevent driver model from + * starting up and this failure is otherwise hard to debug. + */ + return -EPFNOSUPPORT; } uc = calloc(1, sizeof(*uc)); if (!uc)
When a uclass definition is missing, no drivers in that uclass can operate. This can happen if a board has a strange collection of options (e.g. the driver is enabled but the uclass is not). Unfortunately this is very confusing at present. Starting up driver model results in a -ENOENT error, which is pretty generic. Quite a big of digging is needed to get to the root cause. To help with this, change the error to a very strange one with no other users in U-Boot. Also add a debug message. Signed-off-by: Simon Glass <sjg@chromium.org> --- Changes in v5: None Changes in v4: None Changes in v3: None Changes in v2: None drivers/core/device.c | 4 +++- drivers/core/uclass.c | 7 ++++++- 2 files changed, 9 insertions(+), 2 deletions(-)