lkml.org 
[lkml]   [2021]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5/5] nvmem: core: skip child nodes not matching binding
Date
From: Ahmad Fatoum <a.fatoum@pengutronix.de>

The nvmem cell binding applies to all eeprom child nodes matching
"^.*@[0-9a-f]+$" without taking a compatible into account.

Linux drivers, like at24, are even more extensive and assume
_all_ at24 eeprom child nodes to be nvmem cells since e888d445ac33
("nvmem: resolve cells from DT at registration time").

Since df5f3b6f5357 ("dt-bindings: nvmem: stm32: new property for
data access"), the additionalProperties: True means it's Ok to have
other properties as long as they don't match "^.*@[0-9a-f]+$".

The barebox bootloader extends the MTD partitions binding to
EEPROM and can fix up following device tree node:

&eeprom {
partitions {
compatible = "fixed-partitions";
};
};

This is allowed binding-wise, but drivers using nvmem_register()
like at24 will fail to parse because the function expects all child
nodes to have a reg property present. This results in the whole
EEPROM driver probe failing despite the device tree being correct.

Fix this by skipping nodes lacking a reg property instead of
returning an error. This effectively makes the drivers adhere
to the binding because all nodes with a unit address must have
a reg property and vice versa.

Fixes: e888d445ac33 ("nvmem: resolve cells from DT at registration time").
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
drivers/nvmem/core.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 68ae6f24b57f..a5ab1e0c74cf 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -682,7 +682,9 @@ static int nvmem_add_cells_from_of(struct nvmem_device *nvmem)

for_each_child_of_node(parent, child) {
addr = of_get_property(child, "reg", &len);
- if (!addr || (len < 2 * sizeof(u32))) {
+ if (!addr)
+ continue;
+ if (len < 2 * sizeof(u32)) {
dev_err(dev, "nvmem: invalid reg on %pOF\n", child);
return -EINVAL;
}
--
2.21.0
\
 
 \ /
  Last update: 2021-01-29 18:20    [W:0.070 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site