On Mon, 2 Mar 2026 11:38:27 +0100, Kalle Niemi [off-list ref] said:

quoted

On 3/2/26 10:55, Bartosz Golaszewski wrote:  

quoted

On Mon, Mar 2, 2026 at 8:47 AM Kalle Niemi [off-list ref] wrote:  

quoted

On 2/23/26 11:05, Bartosz Golaszewski wrote:  

quoted

In order to stop i2c bus drivers from dereferencing the struct device
embedded in struct i2c_adapter, let's allow configuring the parent
device and OF-node of the adapter directly through dedicated fields.
Signed-off-by: Bartosz Golaszewski <redacted>
---  

Hello,
Automated driver test system bisected this commit to be the first bad
commit, linux-next next-20260227 was tested. Failed tests include driver
tests for ROHM PMIC and accelerometers, which are connected to
BeagleBone Black.
The failed driver tests all fail to first i2cget and the tests stop
there: "Could not open file '/dev/i2c-2' or 'dev/i2c/2': No such file or
directory".  

Wolfram: well, now it would actually be useful to know which commit
exactly is the culprit so maybe splitting the changes is not a bad
idea after all.
Kalle: which i2c bus driver fails here? Any errors in kernel log?
Bart  

Hello Bart,

i2c-1 and i2c-2 are failing. I am not seeing any i2c errors in kernel log. I got two failures without the dmesg available (this is bugged test sequence, and not a kernel crash), but those got the same stdout message "Could not open file ...." as all others.

-Kalle
 

I meant what driver are you using but I suppose it's i2c-omap.

Can you try the following change and let me know if it fixes the issue?

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index dd8cec9b04c6..01656f82d2c6 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c

@@ -1548,6 +1548,11 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
 	if (adap->timeout == 0)
 		adap->timeout = HZ;

+	if (!adap->dev.parent)
+		adap->dev.parent = adap->parent;
+	if (!adap->dev.of_node)
+		adap->dev.of_node = adap->of_node;
+
 	/* register soft irqs for Host Notify */
 	res = i2c_setup_host_notify_irq_domain(adap);
 	if (res) {

@@ -1561,11 +1566,6 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
 	adap->dev.type = &i2c_adapter_type;
 	device_initialize(&adap->dev);

-	if (!adap->dev.parent)
-		adap->dev.parent = adap->parent;
-	if (!adap->dev.of_node)
-		adap->dev.of_node = adap->of_node;
-
 	/*
 	 * This adapter can be used as a parent immediately after device_add(),
 	 * setup runtime-pm (especially ignore-children) before hand.