Re: [PATCH] iio: accel: mma8452: Add single pulse/tap event detection

From: Martin Kepplinger
Date: Fri Nov 10 2017 - 17:35:15 EST


On 2017-11-09 04:12, Harinath Nampally wrote:
> This patch adds following related changes:
> - defines pulse event related registers
> - enables and handles single pulse interrupt for fxls8471
> - handles IIO_EV_DIR_EITHER in read/write callbacks (because
> event direction for pulse is either rising or falling)
> - configures read/write event value for pulse latency register
> using IIO_EV_INFO_HYSTERESIS
> - adds multiple events like pulse and tranient event spec
> as elements of event_spec array named 'mma8452_accel_events'
>
> Except mma8653 chip all other chips like mma845x and
> fxls8471 have single tap detection feature.
> Tested thoroughly using iio_event_monitor application on
> imx6ul-evk board which has fxls8471.
>
> Signed-off-by: Harinath Nampally <harinath922@xxxxxxxxx>
> ---

What tree is this written against? It doesn't apply to the current -next
anyways.

> drivers/iio/accel/mma8452.c | 156 ++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 151 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
> index 43c3a6b..36f1b56 100644
> --- a/drivers/iio/accel/mma8452.c
> +++ b/drivers/iio/accel/mma8452.c
> @@ -72,6 +72,19 @@
> #define MMA8452_TRANSIENT_THS_MASK GENMASK(6, 0)
> #define MMA8452_TRANSIENT_COUNT 0x20
> #define MMA8452_TRANSIENT_CHAN_SHIFT 1
> +#define MMA8452_PULSE_CFG 0x21
> +#define MMA8452_PULSE_CFG_CHAN(chan) BIT(chan * 2)
> +#define MMA8452_PULSE_CFG_ELE BIT(6)
> +#define MMA8452_PULSE_SRC 0x22
> +#define MMA8452_PULSE_SRC_XPULSE BIT(4)
> +#define MMA8452_PULSE_SRC_YPULSE BIT(5)
> +#define MMA8452_PULSE_SRC_ZPULSE BIT(6)
> +#define MMA8452_PULSE_THS 0x23
> +#define MMA8452_PULSE_THS_MASK GENMASK(6, 0)
> +#define MMA8452_PULSE_COUNT 0x26
> +#define MMA8452_PULSE_CHAN_SHIFT 2
> +#define MMA8452_PULSE_LTCY 0x27
> +
> #define MMA8452_CTRL_REG1 0x2a
> #define MMA8452_CTRL_ACTIVE BIT(0)
> #define MMA8452_CTRL_DR_MASK GENMASK(5, 3)
> @@ -91,6 +104,7 @@
>
> #define MMA8452_INT_DRDY BIT(0)
> #define MMA8452_INT_FF_MT BIT(2)
> +#define MMA8452_INT_PULSE BIT(3)
> #define MMA8452_INT_TRANS BIT(5)
>
I think the defintions would deserve to be in a separate patch, but
that's debatable.

> #define MMA8451_DEVICE_ID 0x1a
> @@ -155,6 +169,16 @@ static const struct mma8452_event_regs trans_ev_regs = {
> .ev_count = MMA8452_TRANSIENT_COUNT,
> };
>
> +static const struct mma8452_event_regs pulse_ev_regs = {
> + .ev_cfg = MMA8452_PULSE_CFG,
> + .ev_cfg_ele = MMA8452_PULSE_CFG_ELE,
> + .ev_cfg_chan_shift = MMA8452_PULSE_CHAN_SHIFT,
> + .ev_src = MMA8452_PULSE_SRC,
> + .ev_ths = MMA8452_PULSE_THS,
> + .ev_ths_mask = MMA8452_PULSE_THS_MASK,
> + .ev_count = MMA8452_PULSE_COUNT,
> +};
> +
> /**
> * struct mma_chip_info - chip specific data
> * @chip_id: WHO_AM_I register's value
> @@ -784,6 +808,14 @@ static int mma8452_get_event_regs(struct mma8452_data *data,
> case IIO_EV_DIR_FALLING:
> *ev_reg = &ff_mt_ev_regs;
> return 0;
> + case IIO_EV_DIR_EITHER:
> + if (!(data->chip_info->all_events
> + & MMA8452_INT_PULSE) ||
> + !(data->chip_info->enabled_events
> + & MMA8452_INT_PULSE))
> + return -EINVAL;
> + *ev_reg = &pulse_ev_regs;
> + return 0;
> default:
> return -EINVAL;
> }
> @@ -848,6 +880,25 @@ static int mma8452_read_event_value(struct iio_dev *indio_dev,
> return ret;
> }
>
> + case IIO_EV_INFO_HYSTERESIS:
> + if (!(data->chip_info->all_events & MMA8452_INT_PULSE) ||
> + !(data->chip_info->enabled_events & MMA8452_INT_PULSE))
> + return -EINVAL;
> +
> + ret = i2c_smbus_read_byte_data(data->client,
> + MMA8452_PULSE_LTCY);
> + if (ret < 0)
> + return ret;
> +
> + power_mode = mma8452_get_power_mode(data);
> + if (power_mode < 0)
> + return power_mode;
> +
> + us = ret * mma8452_time_step_us[power_mode][
> + mma8452_get_odr_index(data)];
> + *val = us / USEC_PER_SEC;
> + *val2 = us % USEC_PER_SEC;
> +
> return IIO_VAL_INT_PLUS_MICRO;
>
> default:
> @@ -908,6 +959,24 @@ static int mma8452_write_event_value(struct iio_dev *indio_dev,
>
> return mma8452_change_config(data, MMA8452_TRANSIENT_CFG, reg);
>
> + case IIO_EV_INFO_HYSTERESIS:
> + if (!(data->chip_info->all_events & MMA8452_INT_PULSE) ||
> + !(data->chip_info->enabled_events & MMA8452_INT_PULSE))
> + return -EINVAL;
> +
> + ret = mma8452_get_power_mode(data);
> + if (ret < 0)
> + return ret;
> +
> + steps = (val * USEC_PER_SEC + val2) /
> + mma8452_time_step_us[ret][
> + mma8452_get_odr_index(data)];
> +
> + if (steps < 0 || steps > 0xff)
> + return -EINVAL;
> +
> + return mma8452_change_config(data, MMA8452_PULSE_LTCY, steps);
> +
> default:
> return -EINVAL;
> }
> @@ -937,6 +1006,14 @@ static int mma8452_read_event_config(struct iio_dev *indio_dev,
>
> return !!(ret & BIT(chan->scan_index +
> ev_regs->ev_cfg_chan_shift));
> + case IIO_EV_DIR_EITHER:
> + ret = i2c_smbus_read_byte_data(data->client,
> + ev_regs->ev_cfg);
> + if (ret < 0)
> + return ret;
> +
> + return !!(ret & BIT(chan->scan_index *
> + ev_regs->ev_cfg_chan_shift));
> default:
> return -EINVAL;
> }
> @@ -988,6 +1065,25 @@ static int mma8452_write_event_config(struct iio_dev *indio_dev,
> val |= ev_regs->ev_cfg_ele;
>
> return mma8452_change_config(data, ev_regs->ev_cfg, val);
> +
> + case IIO_EV_DIR_EITHER:
> + val = i2c_smbus_read_byte_data(data->client, ev_regs->ev_cfg);
> + if (val < 0)
> + return val;
> +
> + if (state) {
> + val &= ~BIT(chan->scan_index *
> + ev_regs->ev_cfg_chan_shift);
> + val |= BIT(chan->scan_index *
> + ev_regs->ev_cfg_chan_shift);
> + } else {
> + val &= ~BIT(chan->scan_index *
> + ev_regs->ev_cfg_chan_shift);
> + }
> +
> + val |= ev_regs->ev_cfg_ele;
> +
> + return mma8452_change_config(data, ev_regs->ev_cfg, val);
> default:
> return -EINVAL;
> }
> @@ -1025,6 +1121,38 @@ static void mma8452_transient_interrupt(struct iio_dev *indio_dev)
> ts);
> }
>
> +static void mma8452_pulse_interrupt(struct iio_dev *indio_dev)
> +{
> + struct mma8452_data *data = iio_priv(indio_dev);
> + s64 ts = iio_get_time_ns(indio_dev);
> + int src;
> +
> + src = i2c_smbus_read_byte_data(data->client, MMA8452_PULSE_SRC);
> + if (src < 0)
> + return;
> +
> + if (src & MMA8452_PULSE_SRC_XPULSE)
> + iio_push_event(indio_dev,
> + IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_X,
> + IIO_EV_TYPE_MAG,
> + IIO_EV_DIR_EITHER),
> + ts);
> +
> + if (src & MMA8452_PULSE_SRC_YPULSE)
> + iio_push_event(indio_dev,
> + IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Y,
> + IIO_EV_TYPE_MAG,
> + IIO_EV_DIR_EITHER),
> + ts);
> +
> + if (src & MMA8452_PULSE_SRC_ZPULSE)
> + iio_push_event(indio_dev,
> + IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Z,
> + IIO_EV_TYPE_MAG,
> + IIO_EV_DIR_EITHER),
> + ts);
> +}
> +
> static irqreturn_t mma8452_interrupt(int irq, void *p)
> {
> struct iio_dev *indio_dev = p;
> @@ -1063,6 +1191,11 @@ static irqreturn_t mma8452_interrupt(int irq, void *p)
> ret = IRQ_HANDLED;
> }
>
> + if (src & MMA8452_INT_PULSE) {
> + mma8452_pulse_interrupt(indio_dev);
> + ret = IRQ_HANDLED;
> + }
> +
> return ret;
> }
>
> @@ -1130,8 +1263,10 @@ static const struct iio_event_spec mma8652_freefall_event[] = {
> },
> };
>
> -static const struct iio_event_spec mma8452_transient_event[] = {
> +
> +static const struct iio_event_spec mma8452_accel_events[] = {

I would prefer having this renaming in a separate patch too - with a
good expanation about why. (Don't be afraid of longer commit messages)

> {
> + //trasient event

typo?

> .type = IIO_EV_TYPE_MAG,
> .dir = IIO_EV_DIR_RISING,
> .mask_separate = BIT(IIO_EV_INFO_ENABLE),
> @@ -1139,6 +1274,15 @@ static const struct iio_event_spec mma8452_transient_event[] = {
> BIT(IIO_EV_INFO_PERIOD) |
> BIT(IIO_EV_INFO_HIGH_PASS_FILTER_3DB)
> },
> + {
> + //pulse event
> + .type = IIO_EV_TYPE_MAG,
> + .dir = IIO_EV_DIR_EITHER,
> + .mask_separate = BIT(IIO_EV_INFO_ENABLE),
> + .mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
> + BIT(IIO_EV_INFO_PERIOD) |
> + BIT(IIO_EV_INFO_HYSTERESIS)
> + },
> };
>
> static const struct iio_event_spec mma8452_motion_event[] = {
> @@ -1202,8 +1346,8 @@ static struct attribute_group mma8452_event_attribute_group = {
> .shift = 16 - (bits), \
> .endianness = IIO_BE, \
> }, \
> - .event_spec = mma8452_transient_event, \
> - .num_event_specs = ARRAY_SIZE(mma8452_transient_event), \
> + .event_spec = mma8452_accel_events, \
> + .num_event_specs = ARRAY_SIZE(mma8452_accel_events), \

that would go in the mentioned separate renaming-patch

> }
>
> #define MMA8652_CHANNEL(axis, idx, bits) { \
> @@ -1368,9 +1512,11 @@ static const struct mma_chip_info mma_chip_info_table[] = {
> */
> .all_events = MMA8452_INT_DRDY |
> MMA8452_INT_TRANS |
> - MMA8452_INT_FF_MT,
> + MMA8452_INT_FF_MT |
> + MMA8452_INT_PULSE,
> .enabled_events = MMA8452_INT_TRANS |
> - MMA8452_INT_FF_MT,
> + MMA8452_INT_FF_MT |
> + MMA8452_INT_PULSE,
> },
> };
>
>