From: Ahmad Fatoum a.fatoum@pengutronix.de
[ Upstream commit 0445efacec75b85c2a3c176957ee050ba9be53f0 ]
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 Link: https://lore.kernel.org/r/20210129171430.11328-6-srinivas.kandagatla@linaro.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.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 68ae6f24b57fd..a5ab1e0c74cf6 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; }