[PATCH RFC] gpib: hp82335: check the register mapping before requesting IRQ

[Slavin Liu]

Stop attach on mapping failure before board reset or register access.
The existing detach path handles the reserved region and private state.

Detected by static analysis and reviewed with AI-assisted source auditing.

Fixes: 76319a9d234f ("staging: gpib: Add hp82335x GPIB driver")
Assisted-by: LLM
Signed-off-by: Slavin Liu <bolin.liu@xxxxxxxxxx>
---
 drivers/gpib/hp_82335/hp82335.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpib/hp_82335/hp82335.c b/drivers/gpib/hp_82335/hp82335.c
index b7544b3c15c6..b1ef3dbdcdab 100644
--- a/drivers/gpib/hp_82335/hp82335.c
+++ b/drivers/gpib/hp_82335/hp82335.c
@@ -290,6 +290,8 @@ static int hp82335_attach(struct gpib_board *board, const struct gpib_board_conf
 	}
 	hp_priv->raw_iobase = upper_iomem_base;
 	tms_priv->mmiobase = ioremap(upper_iomem_base, hp82335_upper_iomem_size);
+	if (!tms_priv->mmiobase)
+		return -ENOMEM;
 
 	retval = request_irq(config->ibirq, hp82335_interrupt, 0, DRV_NAME, board);
 	if (retval) {