Subject: [PATCH] input: bma150: Only claim to support the bma180 if the separate iio bma180 driver is not build

From: [email-masked] (Dmitry Torokhov)
Date: Sun, 13 Nov 2016 21:35:23 -0800

Hi Hans,

On Sun, Nov 13, 2016 at 07:34:07PM +0100, Hans de Goede wrote:
> commit ef3714fdbc8d ("Input: bma150 - extend chip detection for bma180"),
> adds bma180 chip-ids to the input bma150 driver, assuming that they are
> 100% compatible, but the bma180 is not compatible with the bma150 at all,
> it has 14 bits resolution instead of 10, and it has quite different
> control registers too.
> 
> Treating the bma180 as a bma150 wrt its data registers will just result
> in throwing away the lowest 4 bits, which is not too bad. But the ctrl
> registers are a different story. Things happen to just work but supporting
> that certainly does not make treating the bma180 the same as the bma150
> right.
> 
> Since some setups depend on the evdev interface the bma150 driver offers
> on top of the bma180, we cannot simply remove the bma180 ids.
> 
> So this commit only removes the bma180 id when the bma180 iio driver,
> which does treat the bma180 properly, is enabled.
> 
> Cc: Dr. H. Nikolaus Schaller <[email-masked]>
> Signed-off-by: Hans de Goede <[email-masked]>
> ---
>  drivers/input/misc/bma150.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/input/misc/bma150.c b/drivers/input/misc/bma150.c
> index b0d4453..9fa1c9a 100644
> --- a/drivers/input/misc/bma150.c
> +++ b/drivers/input/misc/bma150.c
> @@ -539,7 +539,11 @@ static int bma150_probe(struct i2c_client *client,
>  	}
>  
>  	chip_id = i2c_smbus_read_byte_data(client, BMA150_CHIP_ID_REG);
> -	if (chip_id != BMA150_CHIP_ID && chip_id != BMA180_CHIP_ID) {
> +	if (chip_id != BMA150_CHIP_ID
> +#ifndef CONFIG_BMA180
> +	    && chip_id != BMA180_CHIP_ID
> +#endif

Does not this break if bma180 is compiled as module? I'd rather we did

	if (chip_id != BMA150_CHIP_ID &&
            (IS_ENABLED(CONFIG_BMA180) || chip_id != BMA180_CHIP_ID)) {
		...

> +	    ) {
>  		dev_err(&client->dev, "BMA150 chip id error: %d\n", chip_id);
>  		return -EINVAL;
>  	}
> @@ -643,7 +647,9 @@ static UNIVERSAL_DEV_PM_OPS(bma150_pm, bma150_suspend, bma150_resume, NULL);
>  
>  static const struct i2c_device_id bma150_id[] = {
>  	{ "bma150", 0 },
> +#ifndef CONFIG_BMA180
#if !IS_ENABLED(CONFIG_BMA180)

>  	{ "bma180", 0 },
> +#endif
>  	{ "smb380", 0 },
>  	{ "bma023", 0 },
>  	{ }
> -- 
> 2.9.3

Thanks.

-- 
Dmitry