From 6027c077f62f11818a7645151119f8718862d764 Mon Sep 17 00:00:00 2001 From: Srinivas Pandruvada Date: Wed, 19 Mar 2014 16:56:00 +0000 Subject: [PATCH] iio: ak8975 : Add AK8963 compatibility mode support AK8963 and AK8975 use same register definitions, except the range of X,Y,Z values. Added support of 8963 based on i2c_device_id. Unfortunately there is no way to detect the type via registers, both device registers return 0x48 as id of chipset. Signed-off-by: Srinivas Pandruvada Signed-off-by: Jonathan Cameron --- drivers/iio/magnetometer/Kconfig | 3 ++- drivers/iio/magnetometer/ak8975.c | 34 ++++++++++++++++++++++++++----- 2 files changed, 31 insertions(+), 6 deletions(-) diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig index d86d226dcd67..05a364c543f8 100644 --- a/drivers/iio/magnetometer/Kconfig +++ b/drivers/iio/magnetometer/Kconfig @@ -11,7 +11,8 @@ config AK8975 depends on GPIOLIB help Say yes here to build support for Asahi Kasei AK8975 3-Axis - Magnetometer. + Magnetometer. This driver can also support AK8963, if i2c + device name is identified as ak8963. To compile this driver as a module, choose M here: the module will be called ak8975. diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c index 74866d1efd1b..0f1ca5303139 100644 --- a/drivers/iio/magnetometer/ak8975.c +++ b/drivers/iio/magnetometer/ak8975.c @@ -85,7 +85,14 @@ #define AK8975_MAX_CONVERSION_TIMEOUT 500 #define AK8975_CONVERSION_DONE_POLL_TIME 10 #define AK8975_DATA_READY_TIMEOUT ((100*HZ)/1000) -#define RAW_TO_GAUSS(asa) ((((asa) + 128) * 3000) / 256) +#define RAW_TO_GAUSS_8975(asa) ((((asa) + 128) * 3000) / 256) +#define RAW_TO_GAUSS_8963(asa) ((((asa) + 128) * 6000) / 256) + +/* Compatible Asahi Kasei Compass parts */ +enum asahi_compass_chipset { + AK8975, + AK8963, +}; /* * Per-instance context data for the device. @@ -101,6 +108,7 @@ struct ak8975_data { int eoc_irq; wait_queue_head_t data_ready_queue; unsigned long flags; + enum asahi_compass_chipset chipset; }; static const int ak8975_index_to_reg[] = { @@ -272,9 +280,21 @@ static int ak8975_setup(struct i2c_client *client) * Since ASA doesn't change, we cache the resultant scale factor into the * device context in ak8975_setup(). */ - data->raw_to_gauss[0] = RAW_TO_GAUSS(data->asa[0]); - data->raw_to_gauss[1] = RAW_TO_GAUSS(data->asa[1]); - data->raw_to_gauss[2] = RAW_TO_GAUSS(data->asa[2]); + if (data->chipset == AK8963) { + /* + * H range is +-8190 and magnetometer range is +-4912. + * So HuT using the above explanation for 8975, + * 4912/8190 = ~ 6/10. + * So the Hadj should use 6/10 instead of 3/10. + */ + data->raw_to_gauss[0] = RAW_TO_GAUSS_8963(data->asa[0]); + data->raw_to_gauss[1] = RAW_TO_GAUSS_8963(data->asa[1]); + data->raw_to_gauss[2] = RAW_TO_GAUSS_8963(data->asa[2]); + } else { + data->raw_to_gauss[0] = RAW_TO_GAUSS_8975(data->asa[0]); + data->raw_to_gauss[1] = RAW_TO_GAUSS_8975(data->asa[1]); + data->raw_to_gauss[2] = RAW_TO_GAUSS_8975(data->asa[2]); + } return 0; } @@ -499,6 +519,9 @@ static int ak8975_probe(struct i2c_client *client, data->eoc_gpio = eoc_gpio; data->eoc_irq = 0; + data->chipset = (enum asahi_compass_chipset)(id->driver_data); + dev_dbg(&client->dev, "Asahi compass chip %s\n", id->name); + /* Perform some basic start-of-day setup of the device. */ err = ak8975_setup(client); if (err < 0) { @@ -552,7 +575,8 @@ static int ak8975_remove(struct i2c_client *client) } static const struct i2c_device_id ak8975_id[] = { - {"ak8975", 0}, + {"ak8975", AK8975}, + {"ak8963", AK8963}, {} }; -- 2.20.1