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Input: bma150 - remove support for bma150 

This essentially reverts commit baf28d91e7 ("Input: bma150 - avoid
binding to bma180 if IIO bma180 driver present") and commit ef3714fdbc
("Input: bma150 - extend chip detection for bma180")

Rationale: initially (2012) the GTA04 device using a bma180 chip simply
referenced the bma150 platform driver in its board file [1] which happened
to work in all scenarios that were tested.

When conversion to DT started (2014), we needed to make the driver be still
recognised. Hence we introduced the compatibility to the bma180 chip in
Linux 3.15-rc5 [2] without further checks if it is really 100% compatible.
This worked flawlessly for years with the GTA04 device.

Recently (2016), Hans de Goede pointed out that the chips are not as
similar as they appeared and the driver works with the bma180 for the GTA04
only by good luck. He proposed to remove the bma180 support completely [3],
but we still did need it until we have a replacement. Thus, a conditional
compile was added.

We have now developed a generic iio-input-bridge which works with any 2 or
3 axis iio based accelerometer. It has been tested on GTA04 and Pyra and
works as expected. Therefore we can remove the bma180 support from this
driver completely. User-space API compatibility can be restored by using
the iio-input-bridge.

Maybe it is time to convert the bma150 driver to iio as well and retire the
accelerometer input drivers completely but this is a different story and
task.

[1]: https://github.com/neilbrown/linux/blob/gta04/3.2.y/arch/arm/mach-omap2/board-omap3gta04.c#L976
[2]: https://patchwork.kernel.org/patch/3961171/
[3]: https://patchwork.kernel.org/patch/9325481/

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
zero-colors
H. Nikolaus Schaller 2017-04-01 09:43:47 -07:00 committed by Dmitry Torokhov
parent 7e7113f77e
commit f069b5a0b2
1 changed files with 1 additions and 10 deletions
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11
drivers/input/misc/bma150.c
View File

@ -70,7 +70,6 @@
#define BMA150_CFG_5_REG 0x11
#define BMA150_CHIP_ID 2
#define BMA180_CHIP_ID 3
#define BMA150_CHIP_ID_REG BMA150_DATA_0_REG
#define BMA150_ACC_X_LSB_REG BMA150_DATA_2_REG
@ -538,13 +537,8 @@ static int bma150_probe(struct i2c_client *client,
return -EIO;
}
/*
* Note if the IIO CONFIG_BMA180 driver is enabled we want to fail
* the probe for the bma180 as the iio driver is preferred.
*/
chip_id = i2c_smbus_read_byte_data(client, BMA150_CHIP_ID_REG);
if (chip_id != BMA150_CHIP_ID &&
(IS_ENABLED(CONFIG_BMA180) || chip_id != BMA180_CHIP_ID)) {
if (chip_id != BMA150_CHIP_ID) {
dev_err(&client->dev, "BMA150 chip id error: %d\n", chip_id);
return -EINVAL;
}
@ -648,9 +642,6 @@ static UNIVERSAL_DEV_PM_OPS(bma150_pm, bma150_suspend, bma150_resume, NULL);
static const struct i2c_device_id bma150_id[] = {
{ "bma150", 0 },
#if !IS_ENABLED(CONFIG_BMA180)
{ "bma180", 0 },
#endif
{ "smb380", 0 },
{ "bma023", 0 },
{ }