From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from saturn.retrosnub.co.uk ([178.18.118.26]:41393 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752821AbcHOPKF (ORCPT ); Mon, 15 Aug 2016 11:10:05 -0400 Subject: Re: [PATCH 2/2 v5] iio: magn: add a driver for AK8974 To: Linus Walleij , linux-iio@vger.kernel.org References: <1469454895-13659-1-git-send-email-linus.walleij@linaro.org> <1469454895-13659-2-git-send-email-linus.walleij@linaro.org> Cc: Samu Onkalo , Sebastian Reichel , Peter Meerwald-Stadler From: Jonathan Cameron Message-ID: <2b455000-07bf-b766-e969-10012805fc7c@kernel.org> Date: Mon, 15 Aug 2016 16:10:02 +0100 MIME-Version: 1.0 In-Reply-To: <1469454895-13659-2-git-send-email-linus.walleij@linaro.org> Content-Type: text/plain; charset=windows-1252 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 25/07/16 14:54, Linus Walleij wrote: > This adds a driver for the Asahi Kasei AK8975 and its sibling > AMI305 magnetometers. It was deployed on scale in 2009 on a > multitude of devices. It is distincly different from AK8973 > and AK8975 and needs its own driver. AK8975 -> AK8974 (first instance) (I'll fix this up). Does this mean you have an AK8973 driver in the works? :) > > This patch is based on the long lost work of Samu Onkalo at Nokia, > who made a misc character device driver for the Maemo/MeeGo Nokia > devices, before the time of the IIO subsystem. It was mounted in e.g. > the Nokia N950, N8, N86, N97 etc. It is also mounted on the > ST-Ericsson HREF reference designs. > > It works nicely in sysfs: > > $ cat in_magn_x_raw && cat in_magn_y_raw && cat in_magn_z_raw > -55 > -101 > 161 > > And with buffered reads using a simple HRTimer trigger: > $ generic_buffer -c10 -a -n ak8974 -t foo > iio device number being used is 3 > iio trigger number being used is 2 > No channels are enabled, enabling all channels > Enabling: in_magn_x_en > Enabling: in_magn_y_en > Enabling: in_magn_z_en > Enabling: in_timestamp_en > /sys/bus/iio/devices/iio:device3 foo > -58.000000 -102.000000 157.000000 946684970985321044 > -60.000000 -98.000000 159.000000 946684971012237548 > -60.000000 -106.000000 163.000000 946684971032257080 > -62.000000 -94.000000 169.000000 946684971052185058 > -58.000000 -98.000000 163.000000 946684971072204589 > -54.000000 -100.000000 163.000000 946684971092224121 > -53.000000 -103.000000 164.000000 946684971112731933 > -50.000000 -102.000000 165.000000 946684971132232666 > -61.000000 -101.000000 164.000000 946684971152191162 > -57.000000 -99.000000 168.000000 946684971172210693 > Disabling: in_magn_x_en > Disabling: in_magn_y_en > Disabling: in_magn_z_en > Disabling: in_timestamp_en > > I cannot currently scale these raw values to gauss. This is > because of lack of documentation. I have sent a request for > a datasheet to Asahi Kasei. > > The driver can optionally use a DRDY line IRQ to capture data, > else it will sleep and poll. > > Cc: Samu Onkalo > Cc: Sebastian Reichel > Cc: Peter Meerwald-Stadler > Tested-By: Sebastian Reichel > Signed-off-by: Linus Walleij Applied and pushed out as testing for the autobuilders to play with it. Thanks, Jonathan > --- > ChangeLog v4->v5: > - Rebase to master to get the timestamping function to compile. > - Do not convert the values from the sensor on-the-fly to CPU > endianness: tag them as IIO_LE instead. > - Do a single value conversion to CPU endianness for the raw read > interface. > - Fix some bugs on the errorpath where we would return instead of > goto. > - Make all error strings lowercase, add missing \n, fix a speling > mistake in the comments. > ChangeLog v3->v4: > - Add support for an optional mounting matrix > ChangeLog v2->v3: > - Employ the blankline-before-return-if-last-statement-in-a-function > syntax design pattern. > - Join dereferencing of state container struct into a single line > in runtime suspend/resume > - Fix some missing prefixes for ak8974_avdd_reg; etc > - Use GOTO try/catch construction in ak8974_runtime_resume() > - Fix locking issues found by coccinelle > - Speling > ChangeLog v1->v2: > - Drop pointless dependency on GPIOLIB in Kconfig > - Drop the "clever" ret |= returncode code and bail out directly > on any regmap errors > - Add a mutex around measurements so we don't collide, this > could happen atleast in theory > - Inline the read_axes() function into the *read_raw() function > and avoid a pointless helper function > - Augment HW value buffer to be 8*16 bits = 2*64 bits so that it > is aligned to 64bit boundary for the triggered buffer > - Fix a pair of missing if () {} brackets in the runtime resume > function > - Drop erroneous AK8974/5 claim in module description > - Various whitespace fixes > --- > MAINTAINERS | 7 + > drivers/iio/magnetometer/Kconfig | 16 +- > drivers/iio/magnetometer/Makefile | 1 + > drivers/iio/magnetometer/ak8974.c | 863 ++++++++++++++++++++++++++++++++++++++ > 4 files changed, 886 insertions(+), 1 deletion(-) > create mode 100644 drivers/iio/magnetometer/ak8974.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 452beeeb7fbd..cc672f359d9e 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1932,6 +1932,13 @@ S: Maintained > F: drivers/media/i2c/as3645a.c > F: include/media/i2c/as3645a.h > > +ASAHI KASEI AK8974 DRIVER > +M: Linus Walleij > +L: linux-iio@vger.kernel.org > +W: http://www.akm.com/ > +S: Supported > +F: drivers/iio/magnetometer/ak8974.c > + > ASC7621 HARDWARE MONITOR DRIVER > M: George Joseph > L: linux-hwmon@vger.kernel.org > diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig > index 1f842abcb4a4..421ad90a5fbe 100644 > --- a/drivers/iio/magnetometer/Kconfig > +++ b/drivers/iio/magnetometer/Kconfig > @@ -5,8 +5,22 @@ > > menu "Magnetometer sensors" > > +config AK8974 > + tristate "Asahi Kasei AK8974 3-Axis Magnetometer" > + depends on I2C > + depends on OF > + select REGMAP_I2C > + select IIO_BUFFER > + select IIO_TRIGGERED_BUFFER > + help > + Say yes here to build support for Asahi Kasei AK8974 or > + AMI305 I2C-based 3-axis magnetometer chips. > + > + To compile this driver as a module, choose M here: the module > + will be called ak8974. > + > config AK8975 > - tristate "Asahi Kasei AK 3-Axis Magnetometer" > + tristate "Asahi Kasei AK8975 3-Axis Magnetometer" > depends on I2C > depends on GPIOLIB || COMPILE_TEST > select IIO_BUFFER > diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile > index 92a745c9a6e8..b86d6cb7f285 100644 > --- a/drivers/iio/magnetometer/Makefile > +++ b/drivers/iio/magnetometer/Makefile > @@ -3,6 +3,7 @@ > # > > # When adding new entries keep the list in alphabetical order > +obj-$(CONFIG_AK8974) += ak8974.o > obj-$(CONFIG_AK8975) += ak8975.o > obj-$(CONFIG_BMC150_MAGN) += bmc150_magn.o > obj-$(CONFIG_BMC150_MAGN_I2C) += bmc150_magn_i2c.o > diff --git a/drivers/iio/magnetometer/ak8974.c b/drivers/iio/magnetometer/ak8974.c > new file mode 100644 > index 000000000000..e70e4e22b72c > --- /dev/null > +++ b/drivers/iio/magnetometer/ak8974.c > @@ -0,0 +1,863 @@ > +/* > + * Driver for the Asahi Kasei EMD Corporation AK8974 > + * and Aichi Steel AMI305 magnetometer chips. > + * Based on a patch from Samu Onkalo and the AK8975 IIO driver. > + * > + * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). > + * Copyright (c) 2010 NVIDIA Corporation. > + * Copyright (C) 2016 Linaro Ltd. > + * > + * Author: Samu Onkalo > + * Author: Linus Walleij > + */ > +#include > +#include > +#include > +#include > +#include /* For irq_get_irq_data() */ > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* > + * 16-bit registers are little-endian. LSB is at the address defined below > + * and MSB is at the next higher address. > + */ > + > +/* These registers are common for AK8974 and AMI305 */ > +#define AK8974_SELFTEST 0x0C > +#define AK8974_SELFTEST_IDLE 0x55 > +#define AK8974_SELFTEST_OK 0xAA > + > +#define AK8974_INFO 0x0D > + > +#define AK8974_WHOAMI 0x0F > +#define AK8974_WHOAMI_VALUE_AMI305 0x47 > +#define AK8974_WHOAMI_VALUE_AK8974 0x48 > + > +#define AK8974_DATA_X 0x10 > +#define AK8974_DATA_Y 0x12 > +#define AK8974_DATA_Z 0x14 > +#define AK8974_INT_SRC 0x16 > +#define AK8974_STATUS 0x18 > +#define AK8974_INT_CLEAR 0x1A > +#define AK8974_CTRL1 0x1B > +#define AK8974_CTRL2 0x1C > +#define AK8974_CTRL3 0x1D > +#define AK8974_INT_CTRL 0x1E > +#define AK8974_INT_THRES 0x26 /* Absolute any axis value threshold */ > +#define AK8974_PRESET 0x30 > + > +/* AK8974-specific offsets */ > +#define AK8974_OFFSET_X 0x20 > +#define AK8974_OFFSET_Y 0x22 > +#define AK8974_OFFSET_Z 0x24 > +/* AMI305-specific offsets */ > +#define AMI305_OFFSET_X 0x6C > +#define AMI305_OFFSET_Y 0x72 > +#define AMI305_OFFSET_Z 0x78 > + > +/* Different temperature registers */ > +#define AK8974_TEMP 0x31 > +#define AMI305_TEMP 0x60 > + > +#define AK8974_INT_X_HIGH BIT(7) /* Axis over +threshold */ > +#define AK8974_INT_Y_HIGH BIT(6) > +#define AK8974_INT_Z_HIGH BIT(5) > +#define AK8974_INT_X_LOW BIT(4) /* Axis below -threshold */ > +#define AK8974_INT_Y_LOW BIT(3) > +#define AK8974_INT_Z_LOW BIT(2) > +#define AK8974_INT_RANGE BIT(1) /* Range overflow (any axis) */ > + > +#define AK8974_STATUS_DRDY BIT(6) /* Data ready */ > +#define AK8974_STATUS_OVERRUN BIT(5) /* Data overrun */ > +#define AK8974_STATUS_INT BIT(4) /* Interrupt occurred */ > + > +#define AK8974_CTRL1_POWER BIT(7) /* 0 = standby; 1 = active */ > +#define AK8974_CTRL1_RATE BIT(4) /* 0 = 10 Hz; 1 = 20 Hz */ > +#define AK8974_CTRL1_FORCE_EN BIT(1) /* 0 = normal; 1 = force */ > +#define AK8974_CTRL1_MODE2 BIT(0) /* 0 */ > + > +#define AK8974_CTRL2_INT_EN BIT(4) /* 1 = enable interrupts */ > +#define AK8974_CTRL2_DRDY_EN BIT(3) /* 1 = enable data ready signal */ > +#define AK8974_CTRL2_DRDY_POL BIT(2) /* 1 = data ready active high */ > +#define AK8974_CTRL2_RESDEF (AK8974_CTRL2_DRDY_POL) > + > +#define AK8974_CTRL3_RESET BIT(7) /* Software reset */ > +#define AK8974_CTRL3_FORCE BIT(6) /* Start forced measurement */ > +#define AK8974_CTRL3_SELFTEST BIT(4) /* Set selftest register */ > +#define AK8974_CTRL3_RESDEF 0x00 > + > +#define AK8974_INT_CTRL_XEN BIT(7) /* Enable interrupt for this axis */ > +#define AK8974_INT_CTRL_YEN BIT(6) > +#define AK8974_INT_CTRL_ZEN BIT(5) > +#define AK8974_INT_CTRL_XYZEN (BIT(7)|BIT(6)|BIT(5)) > +#define AK8974_INT_CTRL_POL BIT(3) /* 0 = active low; 1 = active high */ > +#define AK8974_INT_CTRL_PULSE BIT(1) /* 0 = latched; 1 = pulse (50 usec) */ > +#define AK8974_INT_CTRL_RESDEF (AK8974_INT_CTRL_XYZEN | AK8974_INT_CTRL_POL) > + > +/* The AMI305 has elaborate FW version and serial number registers */ > +#define AMI305_VER 0xE8 > +#define AMI305_SN 0xEA > + > +#define AK8974_MAX_RANGE 2048 > + > +#define AK8974_POWERON_DELAY 50 > +#define AK8974_ACTIVATE_DELAY 1 > +#define AK8974_SELFTEST_DELAY 1 > +/* > + * Set the autosuspend to two orders of magnitude larger than the poweron > + * delay to make sane reasonable power tradeoff savings (5 seconds in > + * this case). > + */ > +#define AK8974_AUTOSUSPEND_DELAY 5000 > + > +#define AK8974_MEASTIME 3 > + > +#define AK8974_PWR_ON 1 > +#define AK8974_PWR_OFF 0 > + > +/** > + * struct ak8974 - state container for the AK8974 driver > + * @i2c: parent I2C client > + * @orientation: mounting matrix, flipped axis etc > + * @map: regmap to access the AK8974 registers over I2C > + * @regs: the avdd and dvdd power regulators > + * @name: the name of the part > + * @variant: the whoami ID value (for selecting code paths) > + * @lock: locks the magnetometer for exclusive use during a measurement > + * @drdy_irq: uses the DRDY IRQ line > + * @drdy_complete: completion for DRDY > + * @drdy_active_low: the DRDY IRQ is active low > + */ > +struct ak8974 { > + struct i2c_client *i2c; > + struct iio_mount_matrix orientation; > + struct regmap *map; > + struct regulator_bulk_data regs[2]; > + const char *name; > + u8 variant; > + struct mutex lock; > + bool drdy_irq; > + struct completion drdy_complete; > + bool drdy_active_low; > +}; > + > +static const char ak8974_reg_avdd[] = "avdd"; > +static const char ak8974_reg_dvdd[] = "dvdd"; > + > +static int ak8974_set_power(struct ak8974 *ak8974, bool mode) > +{ > + int ret; > + u8 val; > + > + val = mode ? AK8974_CTRL1_POWER : 0; > + val |= AK8974_CTRL1_FORCE_EN; > + ret = regmap_write(ak8974->map, AK8974_CTRL1, val); > + if (ret < 0) > + return ret; > + > + if (mode) > + msleep(AK8974_ACTIVATE_DELAY); > + > + return 0; > +} > + > +static int ak8974_reset(struct ak8974 *ak8974) > +{ > + int ret; > + > + /* Power on to get register access. Sets CTRL1 reg to reset state */ > + ret = ak8974_set_power(ak8974, AK8974_PWR_ON); > + if (ret) > + return ret; > + ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_RESDEF); > + if (ret) > + return ret; > + ret = regmap_write(ak8974->map, AK8974_CTRL3, AK8974_CTRL3_RESDEF); > + if (ret) > + return ret; > + ret = regmap_write(ak8974->map, AK8974_INT_CTRL, > + AK8974_INT_CTRL_RESDEF); > + if (ret) > + return ret; > + > + /* After reset, power off is default state */ > + return ak8974_set_power(ak8974, AK8974_PWR_OFF); > +} > + > +static int ak8974_configure(struct ak8974 *ak8974) > +{ > + int ret; > + > + ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_DRDY_EN | > + AK8974_CTRL2_INT_EN); > + if (ret) > + return ret; > + ret = regmap_write(ak8974->map, AK8974_CTRL3, 0); > + if (ret) > + return ret; > + ret = regmap_write(ak8974->map, AK8974_INT_CTRL, AK8974_INT_CTRL_POL); > + if (ret) > + return ret; > + > + return regmap_write(ak8974->map, AK8974_PRESET, 0); > +} > + > +static int ak8974_trigmeas(struct ak8974 *ak8974) > +{ > + unsigned int clear; > + u8 mask; > + u8 val; > + int ret; > + > + /* Clear any previous measurement overflow status */ > + ret = regmap_read(ak8974->map, AK8974_INT_CLEAR, &clear); > + if (ret) > + return ret; > + > + /* If we have a DRDY IRQ line, use it */ > + if (ak8974->drdy_irq) { > + mask = AK8974_CTRL2_INT_EN | > + AK8974_CTRL2_DRDY_EN | > + AK8974_CTRL2_DRDY_POL; > + val = AK8974_CTRL2_DRDY_EN; > + > + if (!ak8974->drdy_active_low) > + val |= AK8974_CTRL2_DRDY_POL; > + > + init_completion(&ak8974->drdy_complete); > + ret = regmap_update_bits(ak8974->map, AK8974_CTRL2, > + mask, val); > + if (ret) > + return ret; > + } > + > + /* Force a measurement */ > + return regmap_update_bits(ak8974->map, > + AK8974_CTRL3, > + AK8974_CTRL3_FORCE, > + AK8974_CTRL3_FORCE); > +} > + > +static int ak8974_await_drdy(struct ak8974 *ak8974) > +{ > + int timeout = 2; > + unsigned int val; > + int ret; > + > + if (ak8974->drdy_irq) { > + ret = wait_for_completion_timeout(&ak8974->drdy_complete, > + 1 + msecs_to_jiffies(1000)); > + if (!ret) { > + dev_err(&ak8974->i2c->dev, > + "timeout waiting for DRDY IRQ\n"); > + return -ETIMEDOUT; > + } > + return 0; > + } > + > + /* Default delay-based poll loop */ > + do { > + msleep(AK8974_MEASTIME); > + ret = regmap_read(ak8974->map, AK8974_STATUS, &val); > + if (ret < 0) > + return ret; > + if (val & AK8974_STATUS_DRDY) > + return 0; > + } while (--timeout); > + if (!timeout) { > + dev_err(&ak8974->i2c->dev, > + "timeout waiting for DRDY\n"); > + return -ETIMEDOUT; > + } > + > + return 0; > +} > + > +static int ak8974_getresult(struct ak8974 *ak8974, s16 *result) > +{ > + unsigned int src; > + int ret; > + > + ret = ak8974_await_drdy(ak8974); > + if (ret) > + return ret; > + ret = regmap_read(ak8974->map, AK8974_INT_SRC, &src); > + if (ret < 0) > + return ret; > + > + /* Out of range overflow! Strong magnet close? */ > + if (src & AK8974_INT_RANGE) { > + dev_err(&ak8974->i2c->dev, > + "range overflow in sensor\n"); > + return -ERANGE; > + } > + > + ret = regmap_bulk_read(ak8974->map, AK8974_DATA_X, result, 6); > + if (ret) > + return ret; > + > + return ret; > +} > + > +static irqreturn_t ak8974_drdy_irq(int irq, void *d) > +{ > + struct ak8974 *ak8974 = d; > + > + if (!ak8974->drdy_irq) > + return IRQ_NONE; > + > + /* TODO: timestamp here to get good measurement stamps */ > + return IRQ_WAKE_THREAD; > +} > + > +static irqreturn_t ak8974_drdy_irq_thread(int irq, void *d) > +{ > + struct ak8974 *ak8974 = d; > + unsigned int val; > + int ret; > + > + /* Check if this was a DRDY from us */ > + ret = regmap_read(ak8974->map, AK8974_STATUS, &val); > + if (ret < 0) { > + dev_err(&ak8974->i2c->dev, "error reading DRDY status\n"); > + return IRQ_HANDLED; > + } > + if (val & AK8974_STATUS_DRDY) { > + /* Yes this was our IRQ */ > + complete(&ak8974->drdy_complete); > + return IRQ_HANDLED; > + } > + > + /* We may be on a shared IRQ, let the next client check */ > + return IRQ_NONE; > +} > + > +static int ak8974_selftest(struct ak8974 *ak8974) > +{ > + struct device *dev = &ak8974->i2c->dev; > + unsigned int val; > + int ret; > + > + ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val); > + if (ret) > + return ret; > + if (val != AK8974_SELFTEST_IDLE) { > + dev_err(dev, "selftest not idle before test\n"); > + return -EIO; > + } > + > + /* Trigger self-test */ > + ret = regmap_update_bits(ak8974->map, > + AK8974_CTRL3, > + AK8974_CTRL3_SELFTEST, > + AK8974_CTRL3_SELFTEST); > + if (ret) { > + dev_err(dev, "could not write CTRL3\n"); > + return ret; > + } > + > + msleep(AK8974_SELFTEST_DELAY); > + > + ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val); > + if (ret) > + return ret; > + if (val != AK8974_SELFTEST_OK) { > + dev_err(dev, "selftest result NOT OK (%02x)\n", val); > + return -EIO; > + } > + > + ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val); > + if (ret) > + return ret; > + if (val != AK8974_SELFTEST_IDLE) { > + dev_err(dev, "selftest not idle after test (%02x)\n", val); > + return -EIO; > + } > + dev_dbg(dev, "passed self-test\n"); > + > + return 0; > +} > + > +static int ak8974_get_u16_val(struct ak8974 *ak8974, u8 reg, u16 *val) > +{ > + int ret; > + u16 bulk; > + > + ret = regmap_bulk_read(ak8974->map, reg, &bulk, 2); > + if (ret) > + return ret; > + *val = le16_to_cpu(bulk); > + > + return 0; > +} > + > +static int ak8974_detect(struct ak8974 *ak8974) > +{ > + unsigned int whoami; > + const char *name; > + int ret; > + unsigned int fw; > + u16 sn; > + > + ret = regmap_read(ak8974->map, AK8974_WHOAMI, &whoami); > + if (ret) > + return ret; > + > + switch (whoami) { > + case AK8974_WHOAMI_VALUE_AMI305: > + name = "ami305"; > + ret = regmap_read(ak8974->map, AMI305_VER, &fw); > + if (ret) > + return ret; > + fw &= 0x7f; /* only bits 0 thru 6 valid */ > + ret = ak8974_get_u16_val(ak8974, AMI305_SN, &sn); > + if (ret) > + return ret; > + dev_info(&ak8974->i2c->dev, > + "detected %s, FW ver %02x, S/N: %04x\n", > + name, fw, sn); > + break; > + case AK8974_WHOAMI_VALUE_AK8974: > + name = "ak8974"; > + dev_info(&ak8974->i2c->dev, "detected AK8974\n"); > + break; > + default: > + dev_err(&ak8974->i2c->dev, "unsupported device (%02x) ", > + whoami); > + return -ENODEV; > + } > + > + ak8974->name = name; > + ak8974->variant = whoami; > + > + return 0; > +} > + > +static int ak8974_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, > + long mask) > +{ > + struct ak8974 *ak8974 = iio_priv(indio_dev); > + s16 hw_values[3]; > + int ret = -EINVAL; > + > + pm_runtime_get_sync(&ak8974->i2c->dev); > + mutex_lock(&ak8974->lock); > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + if (chan->address > 2) { > + dev_err(&ak8974->i2c->dev, "faulty channel address\n"); > + ret = -EIO; > + goto out_unlock; > + } > + ret = ak8974_trigmeas(ak8974); > + if (ret) > + goto out_unlock; > + ret = ak8974_getresult(ak8974, hw_values); > + if (ret) > + goto out_unlock; > + > + /* > + * We read all axes and discard all but one, for optimized > + * reading, use the triggered buffer. > + */ > + *val = le16_to_cpu(hw_values[chan->address]); > + > + ret = IIO_VAL_INT; > + } > + > + out_unlock: > + mutex_unlock(&ak8974->lock); > + pm_runtime_mark_last_busy(&ak8974->i2c->dev); > + pm_runtime_put_autosuspend(&ak8974->i2c->dev); > + > + return ret; > +} > + > +static void ak8974_fill_buffer(struct iio_dev *indio_dev) > +{ > + struct ak8974 *ak8974 = iio_priv(indio_dev); > + int ret; > + s16 hw_values[8]; /* Three axes + 64bit padding */ > + > + pm_runtime_get_sync(&ak8974->i2c->dev); > + mutex_lock(&ak8974->lock); > + > + ret = ak8974_trigmeas(ak8974); > + if (ret) { > + dev_err(&ak8974->i2c->dev, "error triggering measure\n"); > + goto out_unlock; > + } > + ret = ak8974_getresult(ak8974, hw_values); > + if (ret) { > + dev_err(&ak8974->i2c->dev, "error getting measures\n"); > + goto out_unlock; > + } > + > + iio_push_to_buffers_with_timestamp(indio_dev, hw_values, > + iio_get_time_ns(indio_dev)); > + > + out_unlock: > + mutex_unlock(&ak8974->lock); > + pm_runtime_mark_last_busy(&ak8974->i2c->dev); > + pm_runtime_put_autosuspend(&ak8974->i2c->dev); > +} > + > +static irqreturn_t ak8974_handle_trigger(int irq, void *p) > +{ > + const struct iio_poll_func *pf = p; > + struct iio_dev *indio_dev = pf->indio_dev; > + > + ak8974_fill_buffer(indio_dev); > + iio_trigger_notify_done(indio_dev->trig); > + > + return IRQ_HANDLED; > +} > + > +static const struct iio_mount_matrix * > +ak8974_get_mount_matrix(const struct iio_dev *indio_dev, > + const struct iio_chan_spec *chan) > +{ > + struct ak8974 *ak8974 = iio_priv(indio_dev); > + > + return &ak8974->orientation; > +} > + > +static const struct iio_chan_spec_ext_info ak8974_ext_info[] = { > + IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8974_get_mount_matrix), > + { }, > +}; > + > +#define AK8974_AXIS_CHANNEL(axis, index) \ > + { \ > + .type = IIO_MAGN, \ > + .modified = 1, \ > + .channel2 = IIO_MOD_##axis, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .ext_info = ak8974_ext_info, \ > + .address = index, \ > + .scan_index = index, \ > + .scan_type = { \ > + .sign = 's', \ > + .realbits = 16, \ > + .storagebits = 16, \ > + .endianness = IIO_LE \ > + }, \ > + } > + > +static const struct iio_chan_spec ak8974_channels[] = { > + AK8974_AXIS_CHANNEL(X, 0), > + AK8974_AXIS_CHANNEL(Y, 1), > + AK8974_AXIS_CHANNEL(Z, 2), > + IIO_CHAN_SOFT_TIMESTAMP(3), > +}; > + > +static const unsigned long ak8974_scan_masks[] = { 0x7, 0 }; > + > +static const struct iio_info ak8974_info = { > + .read_raw = &ak8974_read_raw, > + .driver_module = THIS_MODULE, > +}; > + > +static bool ak8974_writeable_reg(struct device *dev, unsigned int reg) > +{ > + struct i2c_client *i2c = to_i2c_client(dev); > + struct iio_dev *indio_dev = i2c_get_clientdata(i2c); > + struct ak8974 *ak8974 = iio_priv(indio_dev); > + > + switch (reg) { > + case AK8974_CTRL1: > + case AK8974_CTRL2: > + case AK8974_CTRL3: > + case AK8974_INT_CTRL: > + case AK8974_INT_THRES: > + case AK8974_INT_THRES + 1: > + case AK8974_PRESET: > + case AK8974_PRESET + 1: > + return true; > + case AK8974_OFFSET_X: > + case AK8974_OFFSET_X + 1: > + case AK8974_OFFSET_Y: > + case AK8974_OFFSET_Y + 1: > + case AK8974_OFFSET_Z: > + case AK8974_OFFSET_Z + 1: > + if (ak8974->variant == AK8974_WHOAMI_VALUE_AK8974) > + return true; > + return false; > + case AMI305_OFFSET_X: > + case AMI305_OFFSET_X + 1: > + case AMI305_OFFSET_Y: > + case AMI305_OFFSET_Y + 1: > + case AMI305_OFFSET_Z: > + case AMI305_OFFSET_Z + 1: > + if (ak8974->variant == AK8974_WHOAMI_VALUE_AMI305) > + return true; > + return false; > + default: > + return false; > + } > +} > + > +static const struct regmap_config ak8974_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > + .max_register = 0xff, > + .writeable_reg = ak8974_writeable_reg, > +}; > + > +static int ak8974_probe(struct i2c_client *i2c, > + const struct i2c_device_id *id) > +{ > + struct iio_dev *indio_dev; > + struct ak8974 *ak8974; > + unsigned long irq_trig; > + int irq = i2c->irq; > + int ret; > + > + /* Register with IIO */ > + indio_dev = devm_iio_device_alloc(&i2c->dev, sizeof(*ak8974)); > + if (indio_dev == NULL) > + return -ENOMEM; > + > + ak8974 = iio_priv(indio_dev); > + i2c_set_clientdata(i2c, indio_dev); > + ak8974->i2c = i2c; > + mutex_init(&ak8974->lock); > + > + ret = of_iio_read_mount_matrix(&i2c->dev, > + "mount-matrix", > + &ak8974->orientation); > + if (ret) > + return ret; > + > + ak8974->regs[0].supply = ak8974_reg_avdd; > + ak8974->regs[1].supply = ak8974_reg_dvdd; > + > + ret = devm_regulator_bulk_get(&i2c->dev, > + ARRAY_SIZE(ak8974->regs), > + ak8974->regs); > + if (ret < 0) { > + dev_err(&i2c->dev, "cannot get regulators\n"); > + return ret; > + } > + > + ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs); > + if (ret < 0) { > + dev_err(&i2c->dev, "cannot enable regulators\n"); > + return ret; > + } > + > + /* Take runtime PM online */ > + pm_runtime_get_noresume(&i2c->dev); > + pm_runtime_set_active(&i2c->dev); > + pm_runtime_enable(&i2c->dev); > + > + ak8974->map = devm_regmap_init_i2c(i2c, &ak8974_regmap_config); > + if (IS_ERR(ak8974->map)) { > + dev_err(&i2c->dev, "failed to allocate register map\n"); > + return PTR_ERR(ak8974->map); > + } > + > + ret = ak8974_set_power(ak8974, AK8974_PWR_ON); > + if (ret) { > + dev_err(&i2c->dev, "could not power on\n"); > + goto power_off; > + } > + > + ret = ak8974_detect(ak8974); > + if (ret) { > + dev_err(&i2c->dev, "neither AK8974 nor AMI305 found\n"); > + goto power_off; > + } > + > + ret = ak8974_selftest(ak8974); > + if (ret) > + dev_err(&i2c->dev, "selftest failed (continuing anyway)\n"); > + > + ret = ak8974_reset(ak8974); > + if (ret) { > + dev_err(&i2c->dev, "AK8974 reset failed\n"); > + goto power_off; > + } > + > + pm_runtime_set_autosuspend_delay(&i2c->dev, > + AK8974_AUTOSUSPEND_DELAY); > + pm_runtime_use_autosuspend(&i2c->dev); > + pm_runtime_put(&i2c->dev); > + > + indio_dev->dev.parent = &i2c->dev; > + indio_dev->channels = ak8974_channels; > + indio_dev->num_channels = ARRAY_SIZE(ak8974_channels); > + indio_dev->info = &ak8974_info; > + indio_dev->available_scan_masks = ak8974_scan_masks; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->name = ak8974->name; > + > + ret = iio_triggered_buffer_setup(indio_dev, NULL, > + ak8974_handle_trigger, > + NULL); > + if (ret) { > + dev_err(&i2c->dev, "triggered buffer setup failed\n"); > + goto disable_pm; > + } > + > + /* If we have a valid DRDY IRQ, make use of it */ > + if (irq > 0) { > + irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq)); > + if (irq_trig == IRQF_TRIGGER_RISING) { > + dev_info(&i2c->dev, "enable rising edge DRDY IRQ\n"); > + } else if (irq_trig == IRQF_TRIGGER_FALLING) { > + ak8974->drdy_active_low = true; > + dev_info(&i2c->dev, "enable falling edge DRDY IRQ\n"); > + } else { > + irq_trig = IRQF_TRIGGER_RISING; > + } > + irq_trig |= IRQF_ONESHOT; > + irq_trig |= IRQF_SHARED; > + > + ret = devm_request_threaded_irq(&i2c->dev, > + irq, > + ak8974_drdy_irq, > + ak8974_drdy_irq_thread, > + irq_trig, > + ak8974->name, > + ak8974); > + if (ret) { > + dev_err(&i2c->dev, "unable to request DRDY IRQ " > + "- proceeding without IRQ\n"); > + goto no_irq; > + } > + ak8974->drdy_irq = true; > + } > + > +no_irq: > + ret = iio_device_register(indio_dev); > + if (ret) { > + dev_err(&i2c->dev, "device register failed\n"); > + goto cleanup_buffer; > + } > + > + return 0; > + > +cleanup_buffer: > + iio_triggered_buffer_cleanup(indio_dev); > +disable_pm: > + pm_runtime_put_noidle(&i2c->dev); > + pm_runtime_disable(&i2c->dev); > + ak8974_set_power(ak8974, AK8974_PWR_OFF); > +power_off: > + regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); > + > + return ret; > +} > + > +static int __exit ak8974_remove(struct i2c_client *i2c) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(i2c); > + struct ak8974 *ak8974 = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + iio_triggered_buffer_cleanup(indio_dev); > + pm_runtime_get_sync(&i2c->dev); > + pm_runtime_put_noidle(&i2c->dev); > + pm_runtime_disable(&i2c->dev); > + ak8974_set_power(ak8974, AK8974_PWR_OFF); > + regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); > + > + return 0; > +} > + > +#ifdef CONFIG_PM > +static int ak8974_runtime_suspend(struct device *dev) > +{ > + struct ak8974 *ak8974 = > + iio_priv(i2c_get_clientdata(to_i2c_client(dev))); > + > + ak8974_set_power(ak8974, AK8974_PWR_OFF); > + regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); > + > + return 0; > +} > + > +static int ak8974_runtime_resume(struct device *dev) > +{ > + struct ak8974 *ak8974 = > + iio_priv(i2c_get_clientdata(to_i2c_client(dev))); > + int ret; > + > + ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs); > + if (ret) > + return ret; > + msleep(AK8974_POWERON_DELAY); > + ret = ak8974_set_power(ak8974, AK8974_PWR_ON); > + if (ret) > + goto out_regulator_disable; > + > + ret = ak8974_configure(ak8974); > + if (ret) > + goto out_disable_power; > + > + return 0; > + > +out_disable_power: > + ak8974_set_power(ak8974, AK8974_PWR_OFF); > +out_regulator_disable: > + regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); > + > + return ret; > +} > +#endif /* CONFIG_PM */ > + > +static const struct dev_pm_ops ak8974_dev_pm_ops = { > + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, > + pm_runtime_force_resume) > + SET_RUNTIME_PM_OPS(ak8974_runtime_suspend, > + ak8974_runtime_resume, NULL) > +}; > + > +static const struct i2c_device_id ak8974_id[] = { > + {"ami305", 0 }, > + {"ak8974", 0 }, > + {} > +}; > +MODULE_DEVICE_TABLE(i2c, ak8974_id); > + > +static const struct of_device_id ak8974_of_match[] = { > + { .compatible = "asahi-kasei,ak8974", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, ak8974_of_match); > + > +static struct i2c_driver ak8974_driver = { > + .driver = { > + .name = "ak8974", > + .owner = THIS_MODULE, > + .pm = &ak8974_dev_pm_ops, > + .of_match_table = of_match_ptr(ak8974_of_match), > + }, > + .probe = ak8974_probe, > + .remove = __exit_p(ak8974_remove), > + .id_table = ak8974_id, > +}; > +module_i2c_driver(ak8974_driver); > + > +MODULE_DESCRIPTION("AK8974 and AMI305 3-axis magnetometer driver"); > +MODULE_AUTHOR("Samu Onkalo"); > +MODULE_AUTHOR("Linus Walleij"); > +MODULE_LICENSE("GPL v2"); >