On Fri, Jul 23, 2021 at 7:35 AM Uwe Kleine-König
[off-list ref] wrote:

On Fri, Jul 23, 2021 at 03:09:44PM +1000, Stephen Rothwell wrote:

quoted

After merging the driver-core tree, today's linux-next build (arm
multi_v7_defconfig) failed like this:

drivers/gpu/drm/drm_dp_aux_bus.c:106:13: error: initialization of 'void (*)(struct device *)' from incompatible pointer type 'int (*)(struct device *)' [-Werror=incompatible-pointer-types]
  106 |  .remove  = dp_aux_ep_remove,
      |             ^~~~~~~~~~~~~~~~
drivers/gpu/drm/drm_dp_aux_bus.c:106:13: note: (near initialization for 'dp_aux_bus_type.remove')

Caused by commit

  aeb33699fc2c ("drm: Introduce the DP AUX bus")

from the drm tree interacting with commit

  fc7a6209d571 ("bus: Make remove callback return void")

from the driver-core tree.

I applied the following merge fix patch.

From: Stephen Rothwell <redacted>
Date: Fri, 23 Jul 2021 14:58:25 +1000
Subject: [PATCH] fix for "drm: Introduce the DP AUX bus"

interaction with "bus: Make remove callback return void"

Signed-off-by: Stephen Rothwell <redacted>
---
 drivers/gpu/drm/drm_dp_aux_bus.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_aux_bus.c b/drivers/gpu/drm/drm_dp_aux_bus.c
index e49a70f3691b..298ea7a49591 100644
--- a/drivers/gpu/drm/drm_dp_aux_bus.c
+++ b/drivers/gpu/drm/drm_dp_aux_bus.c

@@ -67,9 +67,8 @@ static int dp_aux_ep_probe(struct device *dev)
  *
  * Calls through to the endpoint driver remove.
  *
- * Return: 0 if no error or negative error code.
  */
-static int dp_aux_ep_remove(struct device *dev)
+static void dp_aux_ep_remove(struct device *dev)
 {
      struct dp_aux_ep_driver *aux_ep_drv = to_dp_aux_ep_drv(dev->driver);
      struct dp_aux_ep_device *aux_ep = to_dp_aux_ep_dev(dev);

@@ -77,8 +76,6 @@ static int dp_aux_ep_remove(struct device *dev)
      if (aux_ep_drv->remove)
              aux_ep_drv->remove(aux_ep);
      dev_pm_domain_detach(dev, true);
-
-     return 0;
 }

This looks right.

Greg provided a tag containing fc7a6209d571 ("bus: Make remove callback
return void") at

        git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git tags/bus_remove_return_void-5.15

(see https://lore.kernel.org/lkml/YPkwQwf0dUKnGA7L@kroah.com (local)).

It would be great if this could be merged into the drm tree with the
above diff squashed into the merge commit.

+1.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds