/* * MPU3050 gyroscope driver * * Copyright (C) 2016 Linaro Ltd. * Author: Linus Walleij <linus.walleij@linaro.org> * * Based on the input subsystem driver, Copyright (C) 2011 Wistron Co.Ltd * Joseph Lai <joseph_lai@wistron.com> and trimmed down by * Alan Cox <alan@linux.intel.com> in turn based on bma023.c. * Device behaviour based on a misc driver posted by Nathan Royer in 2011. * * TODO: add support for setting up the low pass 3dB frequency. */ #include <linux/bitops.h> #include <linux/delay.h> #include <linux/err.h> #include <linux/iio/buffer.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> #include <linux/iio/trigger.h> #include <linux/iio/trigger_consumer.h> #include <linux/iio/triggered_buffer.h> #include <linux/interrupt.h> #include <linux/module.h> #include <linux/pm_runtime.h> #include <linux/random.h> #include <linux/slab.h> #include "mpu3050.h" #define MPU3050_CHIP_ID 0x69 /* * Register map: anything suffixed *_H is a big-endian high byte and always * followed by the corresponding low byte (*_L) even though these are not * explicitly included in the register definitions. */ #define MPU3050_CHIP_ID_REG 0x00 #define MPU3050_PRODUCT_ID_REG 0x01 #define MPU3050_XG_OFFS_TC 0x05 #define MPU3050_YG_OFFS_TC 0x08 #define MPU3050_ZG_OFFS_TC 0x0B #define MPU3050_X_OFFS_USR_H 0x0C #define MPU3050_Y_OFFS_USR_H 0x0E #define MPU3050_Z_OFFS_USR_H 0x10 #define MPU3050_FIFO_EN 0x12 #define MPU3050_AUX_VDDIO 0x13 #define MPU3050_SLV_ADDR 0x14 #define MPU3050_SMPLRT_DIV 0x15 #define MPU3050_DLPF_FS_SYNC 0x16 #define MPU3050_INT_CFG 0x17 #define MPU3050_AUX_ADDR 0x18 #define MPU3050_INT_STATUS 0x1A #define MPU3050_TEMP_H 0x1B #define MPU3050_XOUT_H 0x1D #define MPU3050_YOUT_H 0x1F #define MPU3050_ZOUT_H 0x21 #define MPU3050_DMP_CFG1 0x35 #define MPU3050_DMP_CFG2 0x36 #define MPU3050_BANK_SEL 0x37 #define MPU3050_MEM_START_ADDR 0x38 #define MPU3050_MEM_R_W 0x39 #define MPU3050_FIFO_COUNT_H 0x3A #define MPU3050_FIFO_R 0x3C #define MPU3050_USR_CTRL 0x3D #define MPU3050_PWR_MGM 0x3E /* MPU memory bank read options */ #define MPU3050_MEM_PRFTCH BIT(5) #define MPU3050_MEM_USER_BANK BIT(4) /* Bits 8-11 select memory bank */ #define MPU3050_MEM_RAM_BANK_0 0 #define MPU3050_MEM_RAM_BANK_1 1 #define MPU3050_MEM_RAM_BANK_2 2 #define MPU3050_MEM_RAM_BANK_3 3 #define MPU3050_MEM_OTP_BANK_0 4 #define MPU3050_AXIS_REGS(axis) (MPU3050_XOUT_H + (axis * 2)) /* Register bits */ /* FIFO Enable */ #define MPU3050_FIFO_EN_FOOTER BIT(0) #define MPU3050_FIFO_EN_AUX_ZOUT BIT(1) #define MPU3050_FIFO_EN_AUX_YOUT BIT(2) #define MPU3050_FIFO_EN_AUX_XOUT BIT(3) #define MPU3050_FIFO_EN_GYRO_ZOUT BIT(4) #define MPU3050_FIFO_EN_GYRO_YOUT BIT(5) #define MPU3050_FIFO_EN_GYRO_XOUT BIT(6) #define MPU3050_FIFO_EN_TEMP_OUT BIT(7) /* * Digital Low Pass filter (DLPF) * Full Scale (FS) * and Synchronization */ #define MPU3050_EXT_SYNC_NONE 0x00 #define MPU3050_EXT_SYNC_TEMP 0x20 #define MPU3050_EXT_SYNC_GYROX 0x40 #define MPU3050_EXT_SYNC_GYROY 0x60 #define MPU3050_EXT_SYNC_GYROZ 0x80 #define MPU3050_EXT_SYNC_ACCELX 0xA0 #define MPU3050_EXT_SYNC_ACCELY 0xC0 #define MPU3050_EXT_SYNC_ACCELZ 0xE0 #define MPU3050_EXT_SYNC_MASK 0xE0 #define MPU3050_EXT_SYNC_SHIFT 5 #define MPU3050_FS_250DPS 0x00 #define MPU3050_FS_500DPS 0x08 #define MPU3050_FS_1000DPS 0x10 #define MPU3050_FS_2000DPS 0x18 #define MPU3050_FS_MASK 0x18 #define MPU3050_FS_SHIFT 3 #define MPU3050_DLPF_CFG_256HZ_NOLPF2 0x00 #define MPU3050_DLPF_CFG_188HZ 0x01 #define MPU3050_DLPF_CFG_98HZ 0x02 #define MPU3050_DLPF_CFG_42HZ 0x03 #define MPU3050_DLPF_CFG_20HZ 0x04 #define MPU3050_DLPF_CFG_10HZ 0x05 #define MPU3050_DLPF_CFG_5HZ 0x06 #define MPU3050_DLPF_CFG_2100HZ_NOLPF 0x07 #define MPU3050_DLPF_CFG_MASK 0x07 #define MPU3050_DLPF_CFG_SHIFT 0 /* Interrupt config */ #define MPU3050_INT_RAW_RDY_EN BIT(0) #define MPU3050_INT_DMP_DONE_EN BIT(1) #define MPU3050_INT_MPU_RDY_EN BIT(2) #define MPU3050_INT_ANYRD_2CLEAR BIT(4) #define MPU3050_INT_LATCH_EN BIT(5) #define MPU3050_INT_OPEN BIT(6) #define MPU3050_INT_ACTL BIT(7) /* Interrupt status */ #define MPU3050_INT_STATUS_RAW_RDY BIT(0) #define MPU3050_INT_STATUS_DMP_DONE BIT(1) #define MPU3050_INT_STATUS_MPU_RDY BIT(2) #define MPU3050_INT_STATUS_FIFO_OVFLW BIT(7) /* USR_CTRL */ #define MPU3050_USR_CTRL_FIFO_EN BIT(6) #define MPU3050_USR_CTRL_AUX_IF_EN BIT(5) #define MPU3050_USR_CTRL_AUX_IF_RST BIT(3) #define MPU3050_USR_CTRL_FIFO_RST BIT(1) #define MPU3050_USR_CTRL_GYRO_RST BIT(0) /* PWR_MGM */ #define MPU3050_PWR_MGM_PLL_X 0x01 #define MPU3050_PWR_MGM_PLL_Y 0x02 #define MPU3050_PWR_MGM_PLL_Z 0x03 #define MPU3050_PWR_MGM_CLKSEL_MASK 0x07 #define MPU3050_PWR_MGM_STBY_ZG BIT(3) #define MPU3050_PWR_MGM_STBY_YG BIT(4) #define MPU3050_PWR_MGM_STBY_XG BIT(5) #define MPU3050_PWR_MGM_SLEEP BIT(6) #define MPU3050_PWR_MGM_RESET BIT(7) #define MPU3050_PWR_MGM_MASK 0xff /* * Fullscale precision is (for finest precision) +/- 250 deg/s, so the full * scale is actually 500 deg/s. All 16 bits are then used to cover this scale, * in two's complement. */ static unsigned int mpu3050_fs_precision[] = { IIO_DEGREE_TO_RAD(250), IIO_DEGREE_TO_RAD(500), IIO_DEGREE_TO_RAD(1000), IIO_DEGREE_TO_RAD(2000) }; /* * Regulator names */ static const char mpu3050_reg_vdd[] = "vdd"; static const char mpu3050_reg_vlogic[] = "vlogic"; static unsigned int mpu3050_get_freq(struct mpu3050 *mpu3050) { unsigned int freq; if (mpu3050->lpf == MPU3050_DLPF_CFG_256HZ_NOLPF2) freq = 8000; else freq = 1000; freq /= (mpu3050->divisor + 1); return freq; } static int mpu3050_start_sampling(struct mpu3050 *mpu3050) { __be16 raw_val[3]; int ret; int i; /* Reset */ ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM, MPU3050_PWR_MGM_RESET, MPU3050_PWR_MGM_RESET); if (ret) return ret; /* Turn on the Z-axis PLL */ ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM, MPU3050_PWR_MGM_CLKSEL_MASK, MPU3050_PWR_MGM_PLL_Z); if (ret) return ret; /* Write calibration offset registers */ for (i = 0; i < 3; i++) raw_val[i] = cpu_to_be16(mpu3050->calibration[i]); ret = regmap_bulk_write(mpu3050->map, MPU3050_X_OFFS_USR_H, raw_val, sizeof(raw_val)); if (ret) return ret; /* Set low pass filter (sample rate), sync and full scale */ ret = regmap_write(mpu3050->map, MPU3050_DLPF_FS_SYNC, MPU3050_EXT_SYNC_NONE << MPU3050_EXT_SYNC_SHIFT | mpu3050->fullscale << MPU3050_FS_SHIFT | mpu3050->lpf << MPU3050_DLPF_CFG_SHIFT); if (ret) return ret; /* Set up sampling frequency */ ret = regmap_write(mpu3050->map, MPU3050_SMPLRT_DIV, mpu3050->divisor); if (ret) return ret; /* * Max 50 ms start-up time after setting DLPF_FS_SYNC * according to the data sheet, then wait for the next sample * at this frequency T = 1000/f ms. */ msleep(50 + 1000 / mpu3050_get_freq(mpu3050)); return 0; } static int mpu3050_set_8khz_samplerate(struct mpu3050 *mpu3050) { int ret; u8 divisor; enum mpu3050_lpf lpf; lpf = mpu3050->lpf; divisor = mpu3050->divisor; mpu3050->lpf = LPF_256_HZ_NOLPF; /* 8 kHz base frequency */ mpu3050->divisor = 0; /* Divide by 1 */ ret = mpu3050_start_sampling(mpu3050); mpu3050->lpf = lpf; mpu3050->divisor = divisor; return ret; } static int mpu3050_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct mpu3050 *mpu3050 = iio_priv(indio_dev); int ret; __be16 raw_val; switch (mask) { case IIO_CHAN_INFO_OFFSET: switch (chan->type) { case IIO_TEMP: /* The temperature scaling is (x+23000)/280 Celsius */ *val = 23000; return IIO_VAL_INT; default: return -EINVAL; } case IIO_CHAN_INFO_CALIBBIAS: switch (chan->type) { case IIO_ANGL_VEL: *val = mpu3050->calibration[chan->scan_index-1]; return IIO_VAL_INT; default: return -EINVAL; } case IIO_CHAN_INFO_SAMP_FREQ: *val = mpu3050_get_freq(mpu3050); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_TEMP: /* Millidegrees, see about temperature scaling above */ *val = 1000; *val2 = 280; return IIO_VAL_FRACTIONAL; case IIO_ANGL_VEL: /* * Convert to the corresponding full scale in * radians. All 16 bits are used with sign to * span the available scale: to account for the one * missing value if we multiply by 1/S16_MAX, instead * multiply with 2/U16_MAX. */ *val = mpu3050_fs_precision[mpu3050->fullscale] * 2; *val2 = U16_MAX; return IIO_VAL_FRACTIONAL; default: return -EINVAL; } case IIO_CHAN_INFO_RAW: /* Resume device */ pm_runtime_get_sync(mpu3050->dev); mutex_lock(&mpu3050->lock); ret = mpu3050_set_8khz_samplerate(mpu3050); if (ret) goto out_read_raw_unlock; switch (chan->type) { case IIO_TEMP: ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H, &raw_val, sizeof(raw_val)); if (ret) { dev_err(mpu3050->dev, "error reading temperature\n"); goto out_read_raw_unlock; } *val = be16_to_cpu(raw_val); ret = IIO_VAL_INT; goto out_read_raw_unlock; case IIO_ANGL_VEL: ret = regmap_bulk_read(mpu3050->map, MPU3050_AXIS_REGS(chan->scan_index-1), &raw_val, sizeof(raw_val)); if (ret) { dev_err(mpu3050->dev, "error reading axis data\n"); goto out_read_raw_unlock; } *val = be16_to_cpu(raw_val); ret = IIO_VAL_INT; goto out_read_raw_unlock; default: ret = -EINVAL; goto out_read_raw_unlock; } default: break; } return -EINVAL; out_read_raw_unlock: mutex_unlock(&mpu3050->lock); pm_runtime_mark_last_busy(mpu3050->dev); pm_runtime_put_autosuspend(mpu3050->dev); return ret; } static int mpu3050_write_raw(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, int val, int val2, long mask) { struct mpu3050 *mpu3050 = iio_priv(indio_dev); /* * Couldn't figure out a way to precalculate these at compile time. */ unsigned int fs250 = DIV_ROUND_CLOSEST(mpu3050_fs_precision[0] * 1000000 * 2, U16_MAX); unsigned int fs500 = DIV_ROUND_CLOSEST(mpu3050_fs_precision[1] * 1000000 * 2, U16_MAX); unsigned int fs1000 = DIV_ROUND_CLOSEST(mpu3050_fs_precision[2] * 1000000 * 2, U16_MAX); unsigned int fs2000 = DIV_ROUND_CLOSEST(mpu3050_fs_precision[3] * 1000000 * 2, U16_MAX); switch (mask) { case IIO_CHAN_INFO_CALIBBIAS: if (chan->type != IIO_ANGL_VEL) return -EINVAL; mpu3050->calibration[chan->scan_index-1] = val; return 0; case IIO_CHAN_INFO_SAMP_FREQ: /* * The max samplerate is 8000 Hz, the minimum * 1000 / 256 ~= 4 Hz */ if (val < 4 || val > 8000) return -EINVAL; /* * Above 1000 Hz we must turn off the digital low pass filter * so we get a base frequency of 8kHz to the divider */ if (val > 1000) { mpu3050->lpf = LPF_256_HZ_NOLPF; mpu3050->divisor = DIV_ROUND_CLOSEST(8000, val) - 1; return 0; } mpu3050->lpf = LPF_188_HZ; mpu3050->divisor = DIV_ROUND_CLOSEST(1000, val) - 1; return 0; case IIO_CHAN_INFO_SCALE: if (chan->type != IIO_ANGL_VEL) return -EINVAL; /* * We support +/-250, +/-500, +/-1000 and +/2000 deg/s * which means we need to round to the closest radians * which will be roughly +/-4.3, +/-8.7, +/-17.5, +/-35 * rad/s. The scale is then for the 16 bits used to cover * it 2/(2^16) of that. */ /* Just too large, set the max range */ if (val != 0) { mpu3050->fullscale = FS_2000_DPS; return 0; } /* * Now we're dealing with fractions below zero in millirad/s * do some integer interpolation and match with the closest * fullscale in the table. */ if (val2 <= fs250 || val2 < ((fs500 + fs250) / 2)) mpu3050->fullscale = FS_250_DPS; else if (val2 <= fs500 || val2 < ((fs1000 + fs500) / 2)) mpu3050->fullscale = FS_500_DPS; else if (val2 <= fs1000 || val2 < ((fs2000 + fs1000) / 2)) mpu3050->fullscale = FS_1000_DPS; else /* Catch-all */ mpu3050->fullscale = FS_2000_DPS; return 0; default: break; } return -EINVAL; } static irqreturn_t mpu3050_trigger_handler(int irq, void *p) { const struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct mpu3050 *mpu3050 = iio_priv(indio_dev); int ret; /* * Temperature 1*16 bits * Three axes 3*16 bits * Timestamp 64 bits (4*16 bits) * Sum total 8*16 bits */ __be16 hw_values[8]; s64 timestamp; unsigned int datums_from_fifo = 0; /* * If we're using the hardware trigger, get the precise timestamp from * the top half of the threaded IRQ handler. Otherwise get the * timestamp here so it will be close in time to the actual values * read from the registers. */ if (iio_trigger_using_own(indio_dev)) timestamp = mpu3050->hw_timestamp; else timestamp = iio_get_time_ns(indio_dev); mutex_lock(&mpu3050->lock); /* Using the hardware IRQ trigger? Check the buffer then. */ if (mpu3050->hw_irq_trigger) { __be16 raw_fifocnt; u16 fifocnt; /* X, Y, Z + temperature */ unsigned int bytes_per_datum = 8; bool fifo_overflow = false; ret = regmap_bulk_read(mpu3050->map, MPU3050_FIFO_COUNT_H, &raw_fifocnt, sizeof(raw_fifocnt)); if (ret) goto out_trigger_unlock; fifocnt = be16_to_cpu(raw_fifocnt); if (fifocnt == 512) { dev_info(mpu3050->dev, "FIFO overflow! Emptying and resetting FIFO\n"); fifo_overflow = true; /* Reset and enable the FIFO */ ret = regmap_update_bits(mpu3050->map, MPU3050_USR_CTRL, MPU3050_USR_CTRL_FIFO_EN | MPU3050_USR_CTRL_FIFO_RST, MPU3050_USR_CTRL_FIFO_EN | MPU3050_USR_CTRL_FIFO_RST); if (ret) { dev_info(mpu3050->dev, "error resetting FIFO\n"); goto out_trigger_unlock; } mpu3050->pending_fifo_footer = false; } if (fifocnt) dev_dbg(mpu3050->dev, "%d bytes in the FIFO\n", fifocnt); while (!fifo_overflow && fifocnt > bytes_per_datum) { unsigned int toread; unsigned int offset; __be16 fifo_values[5]; /* * If there is a FIFO footer in the pipe, first clear * that out. This follows the complex algorithm in the * datasheet that states that you may never leave the * FIFO empty after the first reading: you have to * always leave two footer bytes in it. The footer is * in practice just two zero bytes. */ if (mpu3050->pending_fifo_footer) { toread = bytes_per_datum + 2; offset = 0; } else { toread = bytes_per_datum; offset = 1; /* Put in some dummy value */ fifo_values[0] = 0xAAAA; } ret = regmap_bulk_read(mpu3050->map, MPU3050_FIFO_R, &fifo_values[offset], toread); dev_dbg(mpu3050->dev, "%04x %04x %04x %04x %04x\n", fifo_values[0], fifo_values[1], fifo_values[2], fifo_values[3], fifo_values[4]); /* Index past the footer (fifo_values[0]) and push */ iio_push_to_buffers_with_timestamp(indio_dev, &fifo_values[1], timestamp); fifocnt -= toread; datums_from_fifo++; mpu3050->pending_fifo_footer = true; /* * If we're emptying the FIFO, just make sure to * check if something new appeared. */ if (fifocnt < bytes_per_datum) { ret = regmap_bulk_read(mpu3050->map, MPU3050_FIFO_COUNT_H, &raw_fifocnt, sizeof(raw_fifocnt)); if (ret) goto out_trigger_unlock; fifocnt = be16_to_cpu(raw_fifocnt); } if (fifocnt < bytes_per_datum) dev_dbg(mpu3050->dev, "%d bytes left in the FIFO\n", fifocnt); /* * At this point, the timestamp that triggered the * hardware interrupt is no longer valid for what * we are reading (the interrupt likely fired for * the value on the top of the FIFO), so set the * timestamp to zero and let userspace deal with it. */ timestamp = 0; } } /* * If we picked some datums from the FIFO that's enough, else * fall through and just read from the current value registers. * This happens in two cases: * * - We are using some other trigger (external, like an HRTimer) * than the sensor's own sample generator. In this case the * sensor is just set to the max sampling frequency and we give * the trigger a copy of the latest value every time we get here. * * - The hardware trigger is active but unused and we actually use * another trigger which calls here with a frequency higher * than what the device provides data. We will then just read * duplicate values directly from the hardware registers. */ if (datums_from_fifo) { dev_dbg(mpu3050->dev, "read %d datums from the FIFO\n", datums_from_fifo); goto out_trigger_unlock; } ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H, &hw_values, sizeof(hw_values)); if (ret) { dev_err(mpu3050->dev, "error reading axis data\n"); goto out_trigger_unlock; } iio_push_to_buffers_with_timestamp(indio_dev, hw_values, timestamp); out_trigger_unlock: mutex_unlock(&mpu3050->lock); iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; } static int mpu3050_buffer_preenable(struct iio_dev *indio_dev) { struct mpu3050 *mpu3050 = iio_priv(indio_dev); pm_runtime_get_sync(mpu3050->dev); /* Unless we have OUR trigger active, run at full speed */ if (!mpu3050->hw_irq_trigger) return mpu3050_set_8khz_samplerate(mpu3050); return 0; } static int mpu3050_buffer_postdisable(struct iio_dev *indio_dev) { struct mpu3050 *mpu3050 = iio_priv(indio_dev); pm_runtime_mark_last_busy(mpu3050->dev); pm_runtime_put_autosuspend(mpu3050->dev); return 0; } static const struct iio_buffer_setup_ops mpu3050_buffer_setup_ops = { .preenable = mpu3050_buffer_preenable, .postenable = iio_triggered_buffer_postenable, .predisable = iio_triggered_buffer_predisable, .postdisable = mpu3050_buffer_postdisable, }; static const struct iio_mount_matrix * mpu3050_get_mount_matrix(const struct iio_dev *indio_dev, const struct iio_chan_spec *chan) { struct mpu3050 *mpu3050 = iio_priv(indio_dev); return &mpu3050->orientation; } static const struct iio_chan_spec_ext_info mpu3050_ext_info[] = { IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, mpu3050_get_mount_matrix), { }, }; #define MPU3050_AXIS_CHANNEL(axis, index) \ { \ .type = IIO_ANGL_VEL, \ .modified = 1, \ .channel2 = IIO_MOD_##axis, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ BIT(IIO_CHAN_INFO_CALIBBIAS), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\ .ext_info = mpu3050_ext_info, \ .scan_index = index, \ .scan_type = { \ .sign = 's', \ .realbits = 16, \ .storagebits = 16, \ .endianness = IIO_BE, \ }, \ } static const struct iio_chan_spec mpu3050_channels[] = { { .type = IIO_TEMP, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET), .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), .scan_index = 0, .scan_type = { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE, }, }, MPU3050_AXIS_CHANNEL(X, 1), MPU3050_AXIS_CHANNEL(Y, 2), MPU3050_AXIS_CHANNEL(Z, 3), IIO_CHAN_SOFT_TIMESTAMP(4), }; /* Four channels apart from timestamp, scan mask = 0x0f */ static const unsigned long mpu3050_scan_masks[] = { 0xf, 0 }; /* * These are just the hardcoded factors resulting from the more elaborate * calculations done with fractions in the scale raw get/set functions. */ static IIO_CONST_ATTR(anglevel_scale_available, "0.000122070 " "0.000274658 " "0.000518798 " "0.001068115"); static struct attribute *mpu3050_attributes[] = { &iio_const_attr_anglevel_scale_available.dev_attr.attr, NULL, }; static const struct attribute_group mpu3050_attribute_group = { .attrs = mpu3050_attributes, }; static const struct iio_info mpu3050_info = { .read_raw = mpu3050_read_raw, .write_raw = mpu3050_write_raw, .attrs = &mpu3050_attribute_group, }; /** * mpu3050_read_mem() - read MPU-3050 internal memory * @mpu3050: device to read from * @bank: target bank * @addr: target address * @len: number of bytes * @buf: the buffer to store the read bytes in */ static int mpu3050_read_mem(struct mpu3050 *mpu3050, u8 bank, u8 addr, u8 len, u8 *buf) { int ret; ret = regmap_write(mpu3050->map, MPU3050_BANK_SEL, bank); if (ret) return ret; ret = regmap_write(mpu3050->map, MPU3050_MEM_START_ADDR, addr); if (ret) return ret; return regmap_bulk_read(mpu3050->map, MPU3050_MEM_R_W, buf, len); } static int mpu3050_hw_init(struct mpu3050 *mpu3050) { int ret; u8 otp[8]; /* Reset */ ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM, MPU3050_PWR_MGM_RESET, MPU3050_PWR_MGM_RESET); if (ret) return ret; /* Turn on the PLL */ ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM, MPU3050_PWR_MGM_CLKSEL_MASK, MPU3050_PWR_MGM_PLL_Z); if (ret) return ret; /* Disable IRQs */ ret = regmap_write(mpu3050->map, MPU3050_INT_CFG, 0); if (ret) return ret; /* Read out the 8 bytes of OTP (one-time-programmable) memory */ ret = mpu3050_read_mem(mpu3050, (MPU3050_MEM_PRFTCH | MPU3050_MEM_USER_BANK | MPU3050_MEM_OTP_BANK_0), 0, sizeof(otp), otp); if (ret) return ret; /* This is device-unique data so it goes into the entropy pool */ add_device_randomness(otp, sizeof(otp)); dev_info(mpu3050->dev, "die ID: %04X, wafer ID: %02X, A lot ID: %04X, " "W lot ID: %03X, WP ID: %01X, rev ID: %02X\n", /* Die ID, bits 0-12 */ (otp[1] << 8 | otp[0]) & 0x1fff, /* Wafer ID, bits 13-17 */ ((otp[2] << 8 | otp[1]) & 0x03e0) >> 5, /* A lot ID, bits 18-33 */ ((otp[4] << 16 | otp[3] << 8 | otp[2]) & 0x3fffc) >> 2, /* W lot ID, bits 34-45 */ ((otp[5] << 8 | otp[4]) & 0x3ffc) >> 2, /* WP ID, bits 47-49 */ ((otp[6] << 8 | otp[5]) & 0x0380) >> 7, /* rev ID, bits 50-55 */ otp[6] >> 2); return 0; } static int mpu3050_power_up(struct mpu3050 *mpu3050) { int ret; ret = regulator_bulk_enable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs); if (ret) { dev_err(mpu3050->dev, "cannot enable regulators\n"); return ret; } /* * 20-100 ms start-up time for register read/write according to * the datasheet, be on the safe side and wait 200 ms. */ msleep(200); /* Take device out of sleep mode */ ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM, MPU3050_PWR_MGM_SLEEP, 0); if (ret) { dev_err(mpu3050->dev, "error setting power mode\n"); return ret; } msleep(10); return 0; } static int mpu3050_power_down(struct mpu3050 *mpu3050) { int ret; /* * Put MPU-3050 into sleep mode before cutting regulators. * This is important, because we may not be the sole user * of the regulator so the power may stay on after this, and * then we would be wasting power unless we go to sleep mode * first. */ ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM, MPU3050_PWR_MGM_SLEEP, MPU3050_PWR_MGM_SLEEP); if (ret) dev_err(mpu3050->dev, "error putting to sleep\n"); ret = regulator_bulk_disable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs); if (ret) dev_err(mpu3050->dev, "error disabling regulators\n"); return 0; } static irqreturn_t mpu3050_irq_handler(int irq, void *p) { struct iio_trigger *trig = p; struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); struct mpu3050 *mpu3050 = iio_priv(indio_dev); if (!mpu3050->hw_irq_trigger) return IRQ_NONE; /* Get the time stamp as close in time as possible */ mpu3050->hw_timestamp = iio_get_time_ns(indio_dev); return IRQ_WAKE_THREAD; } static irqreturn_t mpu3050_irq_thread(int irq, void *p) { struct iio_trigger *trig = p; struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); struct mpu3050 *mpu3050 = iio_priv(indio_dev); unsigned int val; int ret; /* ACK IRQ and check if it was from us */ ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val); if (ret) { dev_err(mpu3050->dev, "error reading IRQ status\n"); return IRQ_HANDLED; } if (!(val & MPU3050_INT_STATUS_RAW_RDY)) return IRQ_NONE; iio_trigger_poll_chained(p); return IRQ_HANDLED; } /** * mpu3050_drdy_trigger_set_state() - set data ready interrupt state * @trig: trigger instance * @enable: true if trigger should be enabled, false to disable */ static int mpu3050_drdy_trigger_set_state(struct iio_trigger *trig, bool enable) { struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); struct mpu3050 *mpu3050 = iio_priv(indio_dev); unsigned int val; int ret; /* Disabling trigger: disable interrupt and return */ if (!enable) { /* Disable all interrupts */ ret = regmap_write(mpu3050->map, MPU3050_INT_CFG, 0); if (ret) dev_err(mpu3050->dev, "error disabling IRQ\n"); /* Clear IRQ flag */ ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val); if (ret) dev_err(mpu3050->dev, "error clearing IRQ status\n"); /* Disable all things in the FIFO and reset it */ ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0); if (ret) dev_err(mpu3050->dev, "error disabling FIFO\n"); ret = regmap_write(mpu3050->map, MPU3050_USR_CTRL, MPU3050_USR_CTRL_FIFO_RST); if (ret) dev_err(mpu3050->dev, "error resetting FIFO\n"); pm_runtime_mark_last_busy(mpu3050->dev); pm_runtime_put_autosuspend(mpu3050->dev); mpu3050->hw_irq_trigger = false; return 0; } else { /* Else we're enabling the trigger from this point */ pm_runtime_get_sync(mpu3050->dev); mpu3050->hw_irq_trigger = true; /* Disable all things in the FIFO */ ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0); if (ret) return ret; /* Reset and enable the FIFO */ ret = regmap_update_bits(mpu3050->map, MPU3050_USR_CTRL, MPU3050_USR_CTRL_FIFO_EN | MPU3050_USR_CTRL_FIFO_RST, MPU3050_USR_CTRL_FIFO_EN | MPU3050_USR_CTRL_FIFO_RST); if (ret) return ret; mpu3050->pending_fifo_footer = false; /* Turn on the FIFO for temp+X+Y+Z */ ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, MPU3050_FIFO_EN_TEMP_OUT | MPU3050_FIFO_EN_GYRO_XOUT | MPU3050_FIFO_EN_GYRO_YOUT | MPU3050_FIFO_EN_GYRO_ZOUT | MPU3050_FIFO_EN_FOOTER); if (ret) return ret; /* Configure the sample engine */ ret = mpu3050_start_sampling(mpu3050); if (ret) return ret; /* Clear IRQ flag */ ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val); if (ret) dev_err(mpu3050->dev, "error clearing IRQ status\n"); /* Give us interrupts whenever there is new data ready */ val = MPU3050_INT_RAW_RDY_EN; if (mpu3050->irq_actl) val |= MPU3050_INT_ACTL; if (mpu3050->irq_latch) val |= MPU3050_INT_LATCH_EN; if (mpu3050->irq_opendrain) val |= MPU3050_INT_OPEN; ret = regmap_write(mpu3050->map, MPU3050_INT_CFG, val); if (ret) return ret; } return 0; } static const struct iio_trigger_ops mpu3050_trigger_ops = { .set_trigger_state = mpu3050_drdy_trigger_set_state, }; static int mpu3050_trigger_probe(struct iio_dev *indio_dev, int irq) { struct mpu3050 *mpu3050 = iio_priv(indio_dev); unsigned long irq_trig; int ret; mpu3050->trig = devm_iio_trigger_alloc(&indio_dev->dev, "%s-dev%d", indio_dev->name, indio_dev->id); if (!mpu3050->trig) return -ENOMEM; /* Check if IRQ is open drain */ if (of_property_read_bool(mpu3050->dev->of_node, "drive-open-drain")) mpu3050->irq_opendrain = true; irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq)); /* * Configure the interrupt generator hardware to supply whatever * the interrupt is configured for, edges low/high level low/high, * we can provide it all. */ switch (irq_trig) { case IRQF_TRIGGER_RISING: dev_info(&indio_dev->dev, "pulse interrupts on the rising edge\n"); break; case IRQF_TRIGGER_FALLING: mpu3050->irq_actl = true; dev_info(&indio_dev->dev, "pulse interrupts on the falling edge\n"); break; case IRQF_TRIGGER_HIGH: mpu3050->irq_latch = true; dev_info(&indio_dev->dev, "interrupts active high level\n"); /* * With level IRQs, we mask the IRQ until it is processed, * but with edge IRQs (pulses) we can queue several interrupts * in the top half. */ irq_trig |= IRQF_ONESHOT; break; case IRQF_TRIGGER_LOW: mpu3050->irq_latch = true; mpu3050->irq_actl = true; irq_trig |= IRQF_ONESHOT; dev_info(&indio_dev->dev, "interrupts active low level\n"); break; default: /* This is the most preferred mode, if possible */ dev_err(&indio_dev->dev, "unsupported IRQ trigger specified (%lx), enforce " "rising edge\n", irq_trig); irq_trig = IRQF_TRIGGER_RISING; break; } /* An open drain line can be shared with several devices */ if (mpu3050->irq_opendrain) irq_trig |= IRQF_SHARED; ret = request_threaded_irq(irq, mpu3050_irq_handler, mpu3050_irq_thread, irq_trig, mpu3050->trig->name, mpu3050->trig); if (ret) { dev_err(mpu3050->dev, "can't get IRQ %d, error %d\n", irq, ret); return ret; } mpu3050->irq = irq; mpu3050->trig->dev.parent = mpu3050->dev; mpu3050->trig->ops = &mpu3050_trigger_ops; iio_trigger_set_drvdata(mpu3050->trig, indio_dev); ret = iio_trigger_register(mpu3050->trig); if (ret) return ret; indio_dev->trig = iio_trigger_get(mpu3050->trig); return 0; } int mpu3050_common_probe(struct device *dev, struct regmap *map, int irq, const char *name) { struct iio_dev *indio_dev; struct mpu3050 *mpu3050; unsigned int val; int ret; indio_dev = devm_iio_device_alloc(dev, sizeof(*mpu3050)); if (!indio_dev) return -ENOMEM; mpu3050 = iio_priv(indio_dev); mpu3050->dev = dev; mpu3050->map = map; mutex_init(&mpu3050->lock); /* Default fullscale: 2000 degrees per second */ mpu3050->fullscale = FS_2000_DPS; /* 1 kHz, divide by 100, default frequency = 10 Hz */ mpu3050->lpf = MPU3050_DLPF_CFG_188HZ; mpu3050->divisor = 99; /* Read the mounting matrix, if present */ ret = of_iio_read_mount_matrix(dev, "mount-matrix", &mpu3050->orientation); if (ret) return ret; /* Fetch and turn on regulators */ mpu3050->regs[0].supply = mpu3050_reg_vdd; mpu3050->regs[1].supply = mpu3050_reg_vlogic; ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(mpu3050->regs), mpu3050->regs); if (ret) { dev_err(dev, "Cannot get regulators\n"); return ret; } ret = mpu3050_power_up(mpu3050); if (ret) return ret; ret = regmap_read(map, MPU3050_CHIP_ID_REG, &val); if (ret) { dev_err(dev, "could not read device ID\n"); ret = -ENODEV; goto err_power_down; } if (val != MPU3050_CHIP_ID) { dev_err(dev, "unsupported chip id %02x\n", (u8)val); ret = -ENODEV; goto err_power_down; } ret = regmap_read(map, MPU3050_PRODUCT_ID_REG, &val); if (ret) { dev_err(dev, "could not read device ID\n"); ret = -ENODEV; goto err_power_down; } dev_info(dev, "found MPU-3050 part no: %d, version: %d\n", ((val >> 4) & 0xf), (val & 0xf)); ret = mpu3050_hw_init(mpu3050); if (ret) goto err_power_down; indio_dev->dev.parent = dev; indio_dev->channels = mpu3050_channels; indio_dev->num_channels = ARRAY_SIZE(mpu3050_channels); indio_dev->info = &mpu3050_info; indio_dev->available_scan_masks = mpu3050_scan_masks; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->name = name; ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time, mpu3050_trigger_handler, &mpu3050_buffer_setup_ops); if (ret) { dev_err(dev, "triggered buffer setup failed\n"); goto err_power_down; } ret = iio_device_register(indio_dev); if (ret) { dev_err(dev, "device register failed\n"); goto err_cleanup_buffer; } dev_set_drvdata(dev, indio_dev); /* Check if we have an assigned IRQ to use as trigger */ if (irq) { ret = mpu3050_trigger_probe(indio_dev, irq); if (ret) dev_err(dev, "failed to register trigger\n"); } /* Enable runtime PM */ pm_runtime_get_noresume(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); /* * Set autosuspend to two orders of magnitude larger than the * start-up time. 100ms start-up time means 10000ms autosuspend, * i.e. 10 seconds. */ pm_runtime_set_autosuspend_delay(dev, 10000); pm_runtime_use_autosuspend(dev); pm_runtime_put(dev); return 0; err_cleanup_buffer: iio_triggered_buffer_cleanup(indio_dev); err_power_down: mpu3050_power_down(mpu3050); return ret; } EXPORT_SYMBOL(mpu3050_common_probe); int mpu3050_common_remove(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct mpu3050 *mpu3050 = iio_priv(indio_dev); pm_runtime_get_sync(dev); pm_runtime_put_noidle(dev); pm_runtime_disable(dev); iio_triggered_buffer_cleanup(indio_dev); if (mpu3050->irq) free_irq(mpu3050->irq, mpu3050); iio_device_unregister(indio_dev); mpu3050_power_down(mpu3050); return 0; } EXPORT_SYMBOL(mpu3050_common_remove); #ifdef CONFIG_PM static int mpu3050_runtime_suspend(struct device *dev) { return mpu3050_power_down(iio_priv(dev_get_drvdata(dev))); } static int mpu3050_runtime_resume(struct device *dev) { return mpu3050_power_up(iio_priv(dev_get_drvdata(dev))); } #endif /* CONFIG_PM */ const struct dev_pm_ops mpu3050_dev_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) SET_RUNTIME_PM_OPS(mpu3050_runtime_suspend, mpu3050_runtime_resume, NULL) }; EXPORT_SYMBOL(mpu3050_dev_pm_ops); MODULE_AUTHOR("Linus Walleij"); MODULE_DESCRIPTION("MPU3050 gyroscope driver"); MODULE_LICENSE("GPL");