[PATCH 2/3] can: rcar_canfd: Fix double-cleanup and unclocked register access on init failure

[Biju]

From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>

In rcar_canfd_probe(), if rcar_canfd_global_init() encounters an
error, it disables the clocks and asserts the resets before
returning. However, the probe function then jumps to the fail_mode
label and unconditionally calls rcar_canfd_global_deinit().

The deinit function calls rcar_canfd_disable_global_interrupts(),
which writes to the hardware registers. Since the peripheral clock
has already been disabled by the failed init, this leads to a
synchronous external abort.

Make the rcar_canfd_global_init() failure path jump directly to
fail_dev, skipping the redundant global_deinit() call, since
global_init() has already unwound its own clock/reset state on
error.

Fixes: fa5f4ec8fff8 ("can: rcar_canfd: Extract rcar_canfd_global_{,de}init()")
Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
 drivers/net/can/rcar/rcar_canfd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index 57f1710caa89..e88554388553 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -2257,7 +2257,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 
 	err = rcar_canfd_global_init(gpriv);
 	if (err)
-		goto fail_mode;
+		goto fail_dev;
 
 	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels) {
 		err = rcar_canfd_channel_probe(gpriv, ch, fcan_freq,
@@ -2275,7 +2275,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 fail_channel:
 	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels)
 		rcar_canfd_channel_remove(gpriv, ch);
-fail_mode:
+
 	rcar_canfd_global_deinit(gpriv, false);
 fail_dev:
 	return err;
-- 
2.43.0