RE: [PATCH v7 0/4] Extend device_get_match_data() to struct bus_type

From: Biju Das
Date: Fri Aug 11 2023 - 10:46:19 EST


Hi Andy,

> Subject: Re: [PATCH v7 0/4] Extend device_get_match_data() to struct
> bus_type
>
> On Fri, Aug 11, 2023 at 01:27:36PM +0000, Biju Das wrote:
> > > On Thu, Aug 10, 2023 at 09:05:10AM +0000, Biju Das wrote:
>
> ...
>
> > > I'm good with this approach, but make sure you checked the whole
> > > kernel source tree for a such.
> >
> > Checking against 16 is too short I guess??
> >
> > drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h has 18 enums.
>
> So, what does prevent us from moving that tables to use pointers?

I think that will lead to ABI breakage(client->name vs id->name)

match = device_get_match_data(&client->dev);
if (match) {
chip_type = (uintptr_t)match;
name = client->name;
} else if (id) {
chip_type = (enum inv_devices)
id->driver_data;
name = id->name;
} else {
return -ENOSYS;
}

>
> > /*device enum */
> > enum inv_devices {
> > INV_MPU6050,
> > INV_MPU6500,
> > INV_MPU6515,
> > INV_MPU6880,
> > INV_MPU6000,
> > INV_MPU9150,
> > INV_MPU9250,
> > INV_MPU9255,
> > INV_ICM20608,
> > INV_ICM20608D,
> > INV_ICM20609,
> > INV_ICM20689,
> > INV_ICM20600,
> > INV_ICM20602,
> > INV_ICM20690,
> > INV_IAM20680,
> > INV_NUM_PARTS
> > };
> >
> > The new helper function
>
> You mean for debugging? We don't need that in production.

That is sample code for iterating through id table to find max enum
and check against ZERO_OR_NULL_PTR

>
> I think what you need is a coccinelle script to find these.

I need to explore using coccinelle script as I have n't tried before.

Cheers,
Biju