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Message-ID: <0f778952-1909-1038-8f9a-3a7d7f12d6e1@metafoo.de>
Date:   Mon, 22 Aug 2022 16:08:12 +0200
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Subject: Re: [PATCH 3/3] drivers: iio: adc: Rename the LTC249x iio device
Content-Language: en-US
To:     Ciprian Regus <ciprian.regus@analog.com>, jic23@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, robh+dt@kernel.org,
        linux-iio@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     u.kleine-koenig@pengutronix.de
References: <20220822125106.1106798-1-ciprian.regus@analog.com>
 <20220822125106.1106798-4-ciprian.regus@analog.com>
From:   Lars-Peter Clausen <lars@metafoo.de>
In-Reply-To: <20220822125106.1106798-4-ciprian.regus@analog.com>
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On 8/22/22 14:51, Ciprian Regus wrote:
> Set the iio device's name based on the chip used.

While the change is correct it breaks the ABI. This needs a bit of a 
better explanation what is being done, why, what are the potential 
problems, why do we want to do it anyway.

>
> Signed-off-by: Ciprian Regus <ciprian.regus@analog.com>
> ---
>   drivers/iio/adc/ltc2496.c      | 1 +
>   drivers/iio/adc/ltc2497-core.c | 2 +-
>   drivers/iio/adc/ltc2497.c      | 2 ++
>   drivers/iio/adc/ltc2497.h      | 1 +
>   4 files changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/adc/ltc2496.c b/drivers/iio/adc/ltc2496.c
> index 98338104c24a..86470f49e8ca 100644
> --- a/drivers/iio/adc/ltc2496.c
> +++ b/drivers/iio/adc/ltc2496.c
> @@ -89,6 +89,7 @@ static void ltc2496_remove(struct spi_device *spi)
>   
>   static struct chip_info ltc2496_info = {
>   	.resolution = 16,
> +	.name = "ltc2496"
>   };
>   
>   static const struct of_device_id ltc2496_of_match[] = {
> diff --git a/drivers/iio/adc/ltc2497-core.c b/drivers/iio/adc/ltc2497-core.c
> index b2752399402c..6dd9ab601904 100644
> --- a/drivers/iio/adc/ltc2497-core.c
> +++ b/drivers/iio/adc/ltc2497-core.c
> @@ -169,7 +169,7 @@ int ltc2497core_probe(struct device *dev, struct iio_dev *indio_dev)
>   	struct ltc2497core_driverdata *ddata = iio_priv(indio_dev);
>   	int ret;
>   
> -	indio_dev->name = dev_name(dev);
> +	indio_dev->name = ddata->chip_info->name;
>   	indio_dev->info = &ltc2497core_info;
>   	indio_dev->modes = INDIO_DIRECT_MODE;
>   	indio_dev->channels = ltc2497core_channel;
> diff --git a/drivers/iio/adc/ltc2497.c b/drivers/iio/adc/ltc2497.c
> index bb5e0d4301e2..a0aad71c8130 100644
> --- a/drivers/iio/adc/ltc2497.c
> +++ b/drivers/iio/adc/ltc2497.c
> @@ -99,9 +99,11 @@ static int ltc2497_remove(struct i2c_client *client)
>   static struct chip_info ltc2497_info[] = {
>   	[TYPE_LTC2497] = {
>   		.resolution = 16,
> +		.name = "ltc2497"
>   	},
>   	[TYPE_LTC2499] = {
>   		.resolution = 24,
> +		.name = "ltc2499"
>   	}
>   };
>   
> diff --git a/drivers/iio/adc/ltc2497.h b/drivers/iio/adc/ltc2497.h
> index f4d939cfd48b..0e86e38248ee 100644
> --- a/drivers/iio/adc/ltc2497.h
> +++ b/drivers/iio/adc/ltc2497.h
> @@ -12,6 +12,7 @@ enum chip_type {
>   
>   struct chip_info {
>   	u32 resolution;
> +	char *name;
>   };
>   
>   struct ltc2497core_driverdata {