From: Daniel Matyas <matyasdaniel006@gmail.com>
To: Jaya Kumar <jayalk@intworks.biz>
Cc: Thomas Zimmermann <tzimmermann@suse.de>,
Helge Deller <deller@gmx.de>,
linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
linux-kernel@vger.kernel.org,
Daniel Matyas <matyasdaniel006@gmail.com>
Subject: [PATCH] video: fbdev: Request IO ports
Date: Wed, 11 Nov 2026 17:02:17 +0200 [thread overview]
Message-ID: <20261111150219.239706-1-matyasdaniel006@gmail.com> (raw)
Some fbdev drivers do not request their memory correctly. Request the IO
ports' memory so no other driver may access them. Only request 1 byte,
because the inb() and out() are used for reading and writing.
Did not test on hardware.
Signed-off-by: Daniel Matyas <matyasdaniel006@gmail.com>
---
drivers/video/fbdev/arcfb.c | 8 ++++++++
drivers/video/fbdev/n411.c | 5 +++++
2 files changed, 13 insertions(+)
diff --git a/drivers/video/fbdev/arcfb.c b/drivers/video/fbdev/arcfb.c
index b807cf07522d..6771a7409cde 100644
--- a/drivers/video/fbdev/arcfb.c
+++ b/drivers/video/fbdev/arcfb.c
@@ -481,6 +481,14 @@ static int arcfb_probe(struct platform_device *dev)
printk(KERN_WARNING "no IO addresses supplied\n");
goto err_addr;
}
+
+ if (!devm_request_region(&dev->dev, dio_addr, 1, "arcfb") ||
+ !devm_request_region(&dev->dev, cio_addr, 1, "arcfb") ||
+ !devm_request_region(&dev->dev, c2io_addr, 1, "arcfb")) {
+ retval = -EBUSY;
+ goto err_addr;
+ }
+
par->dio_addr = dio_addr;
par->cio_addr = cio_addr;
par->c2io_addr = c2io_addr;
diff --git a/drivers/video/fbdev/n411.c b/drivers/video/fbdev/n411.c
index a3677313396e..ed0281939d37 100644
--- a/drivers/video/fbdev/n411.c
+++ b/drivers/video/fbdev/n411.c
@@ -165,6 +165,11 @@ static int __init n411_init(void)
if (!n411_device)
return -ENOMEM;
+ if (!devm_request_region(&n411_device->dev, dio_addr, 1, "n411") ||
+ !devm_request_region(&n411_device->dev, cio_addr, 1, "n411") ||
+ !devm_request_region(&n411_device->dev, c2io_addr, 1, "n411"))
+ return -EBUSY;
+
ret = platform_device_add_data(n411_device, &n411_board,
sizeof(n411_board));
if (ret)
--
2.55.0
next reply other threads:[~2026-11-11 15:02 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-11-11 15:02 Daniel Matyas [this message]
2026-11-11 16:14 ` [PATCH] video: fbdev: Request IO ports sashiko-bot
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