On 01/04/2021 at 16:42, Claudiu Beznea - M18063 wrote:

quoted

quoted

+unmap:
+    iounmap(reset->rstc_base);
+    for (idx = 0; idx < ARRAY_SIZE(reset->ramc_base); idx++)
+        iounmap(reset->ramc_base[idx]);

But if we keep this loop, I have the feeling that some kind of
"of_node_put()" is needed as well.

No! In the loop:

for_each_matching_node_and_match(np, at91_ramc_of_match, &match) {
	reset->ramc_lpr = (u32)match->data;
	reset->ramc_base[idx] = of_iomap(np, 0);
	if (!reset->ramc_base[idx]) {
		dev_err(&pdev->dev, "Could not map ram controller address\n");
		of_node_put(np);
		ret = -ENODEV;
		goto unmap;
	}
	idx++;
}

the of_node_put() is needed only if the loop is interrupted as the macro:
for_each_matching_node_and_match() is defined as follows:

#define for_each_matching_node_and_match(dn, matches, match) \
	for (dn = of_find_matching_node_and_match(NULL, matches, match); \
	     dn; dn = of_find_matching_node_and_match(dn, matches, match))

and of_find_matching_node_and_match() will return a np with refcount
incremented but at the next loop step the of_find_matching_node_and_match()
will be called with the same np pointer and the np refcount will be
decremented.

struct device_node *of_find_matching_node_and_match(
		struct device_node *from,
		const struct of_device_id *matches,
		const struct of_device_id **match)
{
	// ...
	of_node_put(from);
	// ...
}

Oh yes you're right Claudiu, I overlooked this one. Thanks for the 
in-depth explanation.

Best regards,
   Nicolas

-- 
Nicolas Ferre