Re: [PATCH v2] drivers/mfd: simple-mfd-i2c: Add generic compatible

From: Jesse Taube
Date: Thu Jan 19 2023 - 16:47:53 EST




On 1/19/23 15:54, Lee Jones wrote:
On Thu, 19 Jan 2023, Rob Herring wrote:

On Fri, Dec 02, 2022 at 06:32:26AM -0500, Jesse Taube wrote:
Some devices may want to use this driver without having a specific
compatible string. Add a generic compatible string to allow this.

What devices need this?

Is that no specific compatible string at all or just in the kernel?
Because the former definitely goes against DT requirements. The latter
enables the former without a schema.


Signed-off-by: Jesse Taube <Mr.Bossman075@xxxxxxxxx>
---
drivers/mfd/simple-mfd-i2c.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
index f4c8fc3ee463..0bda0dd9276e 100644
--- a/drivers/mfd/simple-mfd-i2c.c
+++ b/drivers/mfd/simple-mfd-i2c.c
@@ -73,6 +73,7 @@ static const struct simple_mfd_data silergy_sy7636a = {
};
static const struct of_device_id simple_mfd_i2c_of_match[] = {
+ { .compatible = "simple-mfd-i2c-generic" },

Simple and generic? There is no such device. Anywhere.

This is also not documented which is how I found it (make
dt_compatible_check).
I will write docs if needed.
But this should be reverted or dropped rather than
documented IMO.
Hi Rob, sorry for the disturbance. The reason I submitted this patch is this driver is generic and can be used by many different devices. Adding a generic compatible handle allows device tree writers avoid editing the C source. I also will be submitting device trees that use this in the future if added.
Thanks,
Jesse Taube

I thought it would be better than having a huge list here.

Devices should *also* be allocated a specific compatible string.

$ git grep simple-mfd -- arch