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1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 | // SPDX-License-Identifier: GPL-2.0-only /* * 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 <samu.p.onkalo@nokia.com> * Author: Linus Walleij <linus.walleij@linaro.org> */ #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/kernel.h> #include <linux/i2c.h> #include <linux/interrupt.h> #include <linux/irq.h> /* For irq_get_irq_data() */ #include <linux/completion.h> #include <linux/err.h> #include <linux/mutex.h> #include <linux/delay.h> #include <linux/bitops.h> #include <linux/random.h> #include <linux/regmap.h> #include <linux/regulator/consumer.h> #include <linux/pm_runtime.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> #include <linux/iio/buffer.h> #include <linux/iio/trigger.h> #include <linux/iio/trigger_consumer.h> #include <linux/iio/triggered_buffer.h> /* * 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 AMI30x */ #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_AMI306 0x46 #define AK8974_WHOAMI_VALUE_AMI305 0x47 #define AK8974_WHOAMI_VALUE_AK8974 0x48 #define AK8974_WHOAMI_VALUE_HSCDTD008A 0x49 #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 /* AMI306-specific control register */ #define AMI306_CTRL4 0x5C /* AMI306 factory calibration data */ /* fine axis sensitivity */ #define AMI306_FINEOUTPUT_X 0x90 #define AMI306_FINEOUTPUT_Y 0x92 #define AMI306_FINEOUTPUT_Z 0x94 /* axis sensitivity */ #define AMI306_SENS_X 0x96 #define AMI306_SENS_Y 0x98 #define AMI306_SENS_Z 0x9A /* axis cross-interference */ #define AMI306_GAIN_PARA_XZ 0x9C #define AMI306_GAIN_PARA_XY 0x9D #define AMI306_GAIN_PARA_YZ 0x9E #define AMI306_GAIN_PARA_YX 0x9F #define AMI306_GAIN_PARA_ZY 0xA0 #define AMI306_GAIN_PARA_ZX 0xA1 /* offset at ZERO magnetic field */ #define AMI306_OFFZERO_X 0xF8 #define AMI306_OFFZERO_Y 0xFA #define AMI306_OFFZERO_Z 0xFC #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) /* HSCDTD008A-specific control register */ #define HSCDTD008A_CTRL4 0x1E #define HSCDTD008A_CTRL4_MMD BIT(7) /* must be set to 1 */ #define HSCDTD008A_CTRL4_RANGE BIT(4) /* 0 = 14-bit output; 1 = 15-bit output */ #define HSCDTD008A_CTRL4_RESDEF (HSCDTD008A_CTRL4_MMD | HSCDTD008A_CTRL4_RANGE) /* 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 * @scan: timestamps */ 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; /* Ensure timestamp is naturally aligned */ struct { __le16 channels[3]; s64 ts __aligned(8); } scan; }; static const char ak8974_reg_avdd[] = "avdd"; static const char ak8974_reg_dvdd[] = "dvdd"; static int ak8974_get_u16_val(struct ak8974 *ak8974, u8 reg, u16 *val) { int ret; __le16 bulk; ret = regmap_bulk_read(ak8974->map, reg, &bulk, 2); if (ret) return ret; *val = le16_to_cpu(bulk); return 0; } static int ak8974_set_u16_val(struct ak8974 *ak8974, u8 reg, u16 val) { __le16 bulk = cpu_to_le16(val); return regmap_bulk_write(ak8974->map, reg, &bulk, 2); } 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; if (ak8974->variant != AK8974_WHOAMI_VALUE_HSCDTD008A) { ret = regmap_write(ak8974->map, AK8974_INT_CTRL, AK8974_INT_CTRL_RESDEF); if (ret) return ret; } else { ret = regmap_write(ak8974->map, HSCDTD008A_CTRL4, HSCDTD008A_CTRL4_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; if (ak8974->variant == AK8974_WHOAMI_VALUE_AMI306) { /* magic from datasheet: set high-speed measurement mode */ ret = ak8974_set_u16_val(ak8974, AMI306_CTRL4, 0xA07E); if (ret) return ret; } if (ak8974->variant == AK8974_WHOAMI_VALUE_HSCDTD008A) return 0; 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); dev_err(&ak8974->i2c->dev, "timeout waiting for DRDY\n"); return -ETIMEDOUT; } static int ak8974_getresult(struct ak8974 *ak8974, __le16 *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 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; const char *name; int ret; unsigned int fw; u16 sn; ret = regmap_read(ak8974->map, AK8974_WHOAMI, &whoami); if (ret) return ret; name = "ami305"; switch (whoami) { case AK8974_WHOAMI_VALUE_AMI306: name = "ami306"; fallthrough; case AK8974_WHOAMI_VALUE_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; add_device_randomness(&sn, sizeof(sn)); 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; case AK8974_WHOAMI_VALUE_HSCDTD008A: name = "hscdtd008a"; dev_info(&ak8974->i2c->dev, "detected hscdtd008a\n"); break; default: dev_err(&ak8974->i2c->dev, "unsupported device (%02x) ", whoami); return -ENODEV; } 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; } static int ak8974_measure_channel(struct ak8974 *ak8974, unsigned long address, int *val) { __le16 hw_values[3]; int ret; pm_runtime_get_sync(&ak8974->i2c->dev); mutex_lock(&ak8974->lock); /* * We read all axes and discard all but one, for optimized * reading, use the triggered buffer. */ ret = ak8974_trigmeas(ak8974); if (ret) goto out_unlock; ret = ak8974_getresult(ak8974, hw_values); if (ret) goto out_unlock; /* * This explicit cast to (s16) is necessary as the measurement * is done in 2's complement with positive and negative values. * The follwing assignment to *val will then convert the signed * s16 value to a signed int value. */ *val = (s16)le16_to_cpu(hw_values[address]); out_unlock: mutex_unlock(&ak8974->lock); pm_runtime_mark_last_busy(&ak8974->i2c->dev); pm_runtime_put_autosuspend(&ak8974->i2c->dev); return ret; } 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); int ret; switch (mask) { case IIO_CHAN_INFO_RAW: if (chan->address > 2) { dev_err(&ak8974->i2c->dev, "faulty channel address\n"); return -EIO; } ret = ak8974_measure_channel(ak8974, chan->address, val); if (ret) return ret; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: switch (ak8974->variant) { case AK8974_WHOAMI_VALUE_AMI306: case AK8974_WHOAMI_VALUE_AMI305: /* * The datasheet for AMI305 and AMI306, page 6 * specifies the range of the sensor to be * +/- 12 Gauss. */ *val = 12; /* * 12 bits are used, +/- 2^11 * [ -2048 .. 2047 ] (manual page 20) * [ 0xf800 .. 0x07ff ] */ *val2 = 11; return IIO_VAL_FRACTIONAL_LOG2; case AK8974_WHOAMI_VALUE_HSCDTD008A: /* * The datasheet for HSCDTF008A, page 3 specifies the * range of the sensor as +/- 2.4 mT per axis, which * corresponds to +/- 2400 uT = +/- 24 Gauss. */ *val = 24; /* * 15 bits are used (set up in CTRL4), +/- 2^14 * [ -16384 .. 16383 ] (manual page 24) * [ 0xc000 .. 0x3fff ] */ *val2 = 14; return IIO_VAL_FRACTIONAL_LOG2; default: /* GUESSING +/- 12 Gauss */ *val = 12; /* GUESSING 12 bits ADC +/- 2^11 */ *val2 = 11; return IIO_VAL_FRACTIONAL_LOG2; } break; default: /* Unknown request */ break; } return -EINVAL; } static void ak8974_fill_buffer(struct iio_dev *indio_dev) { struct ak8974 *ak8974 = iio_priv(indio_dev); int ret; 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, ak8974->scan.channels); if (ret) { dev_err(&ak8974->i2c->dev, "error getting measures\n"); goto out_unlock; } iio_push_to_buffers_with_timestamp(indio_dev, &ak8974->scan, 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, bits) \ { \ .type = IIO_MAGN, \ .modified = 1, \ .channel2 = IIO_MOD_##axis, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ BIT(IIO_CHAN_INFO_SCALE), \ .ext_info = ak8974_ext_info, \ .address = index, \ .scan_index = index, \ .scan_type = { \ .sign = 's', \ .realbits = bits, \ .storagebits = 16, \ .endianness = IIO_LE \ }, \ } /* * We have no datasheet for the AK8974 but we guess that its * ADC is 12 bits. The AMI305 and AMI306 certainly has 12bit * ADC. */ static const struct iio_chan_spec ak8974_12_bits_channels[] = { AK8974_AXIS_CHANNEL(X, 0, 12), AK8974_AXIS_CHANNEL(Y, 1, 12), AK8974_AXIS_CHANNEL(Z, 2, 12), IIO_CHAN_SOFT_TIMESTAMP(3), }; /* * The HSCDTD008A has 15 bits resolution the way we set it up * in CTRL4. */ static const struct iio_chan_spec ak8974_15_bits_channels[] = { AK8974_AXIS_CHANNEL(X, 0, 15), AK8974_AXIS_CHANNEL(Y, 1, 15), AK8974_AXIS_CHANNEL(Z, 2, 15), 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, }; 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: return true; case AK8974_PRESET: case AK8974_PRESET + 1: return ak8974->variant != AK8974_WHOAMI_VALUE_HSCDTD008A; 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: return ak8974->variant == AK8974_WHOAMI_VALUE_AK8974 || ak8974->variant == AK8974_WHOAMI_VALUE_HSCDTD008A; 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: return ak8974->variant == AK8974_WHOAMI_VALUE_AMI305 || ak8974->variant == AK8974_WHOAMI_VALUE_AMI306; case AMI306_CTRL4: case AMI306_CTRL4 + 1: return ak8974->variant == AK8974_WHOAMI_VALUE_AMI306; default: return false; } } static bool ak8974_precious_reg(struct device *dev, unsigned int reg) { return reg == AK8974_INT_CLEAR; } static const struct regmap_config ak8974_regmap_config = { .reg_bits = 8, .val_bits = 8, .max_register = 0xff, .writeable_reg = ak8974_writeable_reg, .precious_reg = ak8974_precious_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 = iio_read_mount_matrix(&i2c->dev, &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) return dev_err_probe(&i2c->dev, ret, "cannot get regulators\n"); 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"); pm_runtime_put_noidle(&i2c->dev); pm_runtime_disable(&i2c->dev); 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 disable_pm; } ret = ak8974_detect(ak8974); if (ret) { dev_err(&i2c->dev, "neither AK8974 nor AMI30x found\n"); goto disable_pm; } 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 disable_pm; } switch (ak8974->variant) { case AK8974_WHOAMI_VALUE_AMI306: case AK8974_WHOAMI_VALUE_AMI305: indio_dev->channels = ak8974_12_bits_channels; indio_dev->num_channels = ARRAY_SIZE(ak8974_12_bits_channels); break; case AK8974_WHOAMI_VALUE_HSCDTD008A: indio_dev->channels = ak8974_15_bits_channels; indio_dev->num_channels = ARRAY_SIZE(ak8974_15_bits_channels); break; default: indio_dev->channels = ak8974_12_bits_channels; indio_dev->num_channels = ARRAY_SIZE(ak8974_12_bits_channels); break; } 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; } pm_runtime_set_autosuspend_delay(&i2c->dev, AK8974_AUTOSUSPEND_DELAY); pm_runtime_use_autosuspend(&i2c->dev); pm_runtime_put(&i2c->dev); 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); regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); return ret; } static int 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; } static int __maybe_unused 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 __maybe_unused 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; } 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 }, {"ami306", 0 }, {"ak8974", 0 }, {"hscdtd008a", 0 }, {} }; MODULE_DEVICE_TABLE(i2c, ak8974_id); static const struct of_device_id ak8974_of_match[] = { { .compatible = "asahi-kasei,ak8974", }, { .compatible = "alps,hscdtd008a", }, {} }; MODULE_DEVICE_TABLE(of, ak8974_of_match); static struct i2c_driver ak8974_driver = { .driver = { .name = "ak8974", .pm = &ak8974_dev_pm_ops, .of_match_table = ak8974_of_match, }, .probe = ak8974_probe, .remove = ak8974_remove, .id_table = ak8974_id, }; module_i2c_driver(ak8974_driver); MODULE_DESCRIPTION("AK8974 and AMI30x 3-axis magnetometer driver"); MODULE_AUTHOR("Samu Onkalo"); MODULE_AUTHOR("Linus Walleij"); MODULE_LICENSE("GPL v2"); |