From 0a60340f199136e7b74f4b279e3844abf2d45485 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Micha=C5=82=20Miros=C5=82aw?= Date: Thu, 17 Aug 2017 15:56:12 +0200 Subject: [PATCH] iio: magnetometer: ak8974: debug AMI306 calibration data MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Use AMI306 calibration data for randomness and debugging. Signed-off-by: Michał Mirosław Reviewed-by: Linus Walleij Signed-off-by: Jonathan Cameron --- drivers/iio/magnetometer/ak8974.c | 41 +++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/drivers/iio/magnetometer/ak8974.c b/drivers/iio/magnetometer/ak8974.c index 866f20b818b1..0bff76e96950 100644 --- a/drivers/iio/magnetometer/ak8974.c +++ b/drivers/iio/magnetometer/ak8974.c @@ -445,6 +445,20 @@ static int ak8974_selftest(struct ak8974 *ak8974) return 0; } +static void ak8974_read_calib_data(struct ak8974 *ak8974, unsigned int reg, + __le16 *tab, size_t tab_size) +{ + int ret = regmap_bulk_read(ak8974->map, reg, tab, tab_size); + if (ret) { + memset(tab, 0xFF, tab_size); + dev_warn(&ak8974->i2c->dev, + "can't read calibration data (regs %u..%zu): %d\n", + reg, reg + tab_size - 1, ret); + } else { + add_device_randomness(tab, tab_size); + } +} + static int ak8974_detect(struct ak8974 *ak8974) { unsigned int whoami; @@ -489,6 +503,33 @@ static int ak8974_detect(struct ak8974 *ak8974) ak8974->name = name; ak8974->variant = whoami; + if (whoami == AK8974_WHOAMI_VALUE_AMI306) { + __le16 fab_data1[9], fab_data2[3]; + int i; + + ak8974_read_calib_data(ak8974, AMI306_FINEOUTPUT_X, + fab_data1, sizeof(fab_data1)); + ak8974_read_calib_data(ak8974, AMI306_OFFZERO_X, + fab_data2, sizeof(fab_data2)); + + for (i = 0; i < 3; ++i) { + static const char axis[3] = "XYZ"; + static const char pgaxis[6] = "ZYZXYX"; + unsigned offz = le16_to_cpu(fab_data2[i]) & 0x7F; + unsigned fine = le16_to_cpu(fab_data1[i]); + unsigned sens = le16_to_cpu(fab_data1[i + 3]); + unsigned pgain1 = le16_to_cpu(fab_data1[i + 6]); + unsigned pgain2 = pgain1 >> 8; + + pgain1 &= 0xFF; + + dev_info(&ak8974->i2c->dev, + "factory calibration for axis %c: offz=%u sens=%u fine=%u pga%c=%u pga%c=%u\n", + axis[i], offz, sens, fine, pgaxis[i * 2], + pgain1, pgaxis[i * 2 + 1], pgain2); + } + } + return 0; } -- 2.20.1