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    c06a6aba
    iio: accel: bmc150: Drop misleading/duplicate chip identifiers · c06a6aba
    Stephan Gerhold authored
    
    
    Commit 0ad4bf37 ("iio:accel:bmc150-accel: Use the chip ID to detect
    sensor variant") stopped using the I2C/ACPI match data to look up the
    bmc150_accel_chip_info. However, the bmc150_accel_chip_info_tbl remained
    as-is, with multiple entries with the same chip_id (e.g. 0xFA for
    BMC150/BMI055/BMA255). This is redundant now because actually the driver
    will always select the first entry with a matching chip_id.
    
    So even if a device probes e.g. with BMA0255 it will end up using the
    chip_info for BMC150. And in general that's fine for now, the entries
    for BMC150/BMI055/BMA255 were exactly the same anyway (except for the
    name, which is replaced with the more accurate one later).
    
    But in this case it's misleading because it suggests that one should
    add even more entries with the same chip_id when adding support for
    new variants. Let's make that more clear by removing the enum with
    the chip identifiers entirely and instead have only one entry per
    chip_id.
    
    Note that we may need to bring back some mechanism to differentiate
    between different chips with the same chip_id in the future.
    For example, BMA250 (currently supported by the bma180 driver) has the
    same chip_id = 0x03 as BMA222 even though they have different channel
    sizes (8 bits vs 10 bits). But in any case, that mechanism would
    need to look quite different from what we have right now.
    
    Cc: Bastien Nocera <hadess@hadess.net>
    Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
    Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
    Signed-off-by: default avatarStephan Gerhold <stephan@gerhold.net>
    Link: https://lore.kernel.org/r/20210611080903.14384-4-stephan@gerhold.net
    
    
    Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
    c06a6aba
    iio: accel: bmc150: Drop misleading/duplicate chip identifiers
    Stephan Gerhold authored
    
    
    Commit 0ad4bf37 ("iio:accel:bmc150-accel: Use the chip ID to detect
    sensor variant") stopped using the I2C/ACPI match data to look up the
    bmc150_accel_chip_info. However, the bmc150_accel_chip_info_tbl remained
    as-is, with multiple entries with the same chip_id (e.g. 0xFA for
    BMC150/BMI055/BMA255). This is redundant now because actually the driver
    will always select the first entry with a matching chip_id.
    
    So even if a device probes e.g. with BMA0255 it will end up using the
    chip_info for BMC150. And in general that's fine for now, the entries
    for BMC150/BMI055/BMA255 were exactly the same anyway (except for the
    name, which is replaced with the more accurate one later).
    
    But in this case it's misleading because it suggests that one should
    add even more entries with the same chip_id when adding support for
    new variants. Let's make that more clear by removing the enum with
    the chip identifiers entirely and instead have only one entry per
    chip_id.
    
    Note that we may need to bring back some mechanism to differentiate
    between different chips with the same chip_id in the future.
    For example, BMA250 (currently supported by the bma180 driver) has the
    same chip_id = 0x03 as BMA222 even though they have different channel
    sizes (8 bits vs 10 bits). But in any case, that mechanism would
    need to look quite different from what we have right now.
    
    Cc: Bastien Nocera <hadess@hadess.net>
    Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
    Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
    Signed-off-by: default avatarStephan Gerhold <stephan@gerhold.net>
    Link: https://lore.kernel.org/r/20210611080903.14384-4-stephan@gerhold.net
    
    
    Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
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