From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com ([134.134.136.20]:6365 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755177AbaCKVNb (ORCPT ); Tue, 11 Mar 2014 17:13:31 -0400 From: Srinivas Pandruvada To: jic23@kernel.org Cc: linux-iio@vger.kernel.org, Srinivas Pandruvada Subject: [PATCH 1/3] iio: ak8975 : Add AK8963 compatibility mode support Date: Tue, 11 Mar 2014 14:15:55 -0700 Message-Id: <1394572557-8102-1-git-send-email-srinivas.pandruvada@linux.intel.com> Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org 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 --- drivers/iio/magnetometer/Kconfig | 3 ++- drivers/iio/magnetometer/ak8975.c | 40 +++++++++++++++++++++++++++++++++++---- 2 files changed, 38 insertions(+), 5 deletions(-) diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig index d86d226..05a364c54 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 0542354..a55c94f 100644 --- a/drivers/iio/magnetometer/ak8975.c +++ b/drivers/iio/magnetometer/ak8975.c @@ -85,7 +85,15 @@ #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, + AK_INVALID, +}; /* * Per-instance context data for the device. @@ -101,6 +109,7 @@ struct ak8975_data { int eoc_irq; wait_queue_head_t data_ready_queue; unsigned long flags; + int chipset; }; static const int ak8975_index_to_reg[] = { @@ -272,9 +281,21 @@ 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 +520,16 @@ static int ak8975_probe(struct i2c_client *client, data->eoc_gpio = eoc_gpio; data->eoc_irq = 0; + if (id) { + data->chipset = (int)(id->driver_data); + if (data->chipset == AK8963) + dev_dbg(&client->dev, + "AK8975 driver is running in AK8963 mode\n"); + else + dev_dbg(&client->dev, + "AK8975 driver is running in normal mode\n"); + } + /* Perform some basic start-of-day setup of the device. */ err = ak8975_setup(client); if (err < 0) { @@ -552,6 +583,7 @@ static int ak8975_remove(struct i2c_client *client) static const struct i2c_device_id ak8975_id[] = { {"ak8975", 0}, + {"ak8963", AK8963}, {} }; -- 1.7.11.7