[PATCH v5 07/15] iio: sx9310: Use long instead of int for channel bitmaps

Daniel Campello
2020-08-03T23:59:06Z

Uses for_each_set_bit() macro to loop over channel bitmaps.

Signed-off-by: Daniel Campello <campello@chromium.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
---

Changes in v5: None
Changes in v4: None
Changes in v3:
- Added static assert for number of channels.

Changes in v2:
- Changed prox_stat to chan_prox_stat bitmap.

drivers/iio/proximity/sx9310.c | 39 ++++++++++++++++++----------------
1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c
index 127b1ba79e2dea..f78500b8a5841e 100644
--- a/drivers/iio/proximity/sx9310.c
+++ b/drivers/iio/proximity/sx9310.c
@@ -119,6 +119,7 @@

/* 4 hardware channels, as defined in STAT0: COMB, CS2, CS1 and CS0. */
#define SX9310_NUM_CHANNELS 4
+static_assert(SX9310_NUM_CHANNELS < BITS_PER_LONG);

struct sx9310_data {
/* Serialize access to registers and channel configuration */
@@ -130,7 +131,7 @@ struct sx9310_data {
* Last reading of the proximity status for each channel.
* We only send an event to user space when this changes.
*/
- bool prox_stat[SX9310_NUM_CHANNELS];
+ unsigned long chan_prox_stat;
bool trigger_enabled;
/* Ensure correct alignment of timestamp when present. */
struct {
@@ -140,7 +141,8 @@ struct sx9310_data {
/* Remember enabled channels and sample rate during suspend. */
unsigned int suspend_ctrl0;
struct completion completion;
- unsigned int chan_read, chan_event;
+ unsigned long chan_read;
+ unsigned long chan_event;
int channel_users[SX9310_NUM_CHANNELS];
unsigned int whoami;
};
@@ -283,15 +285,16 @@ static const struct regmap_config sx9310_regmap_config = {
};

static int sx9310_update_chan_en(struct sx9310_data *data,
- unsigned int chan_read,
- unsigned int chan_event)
+ unsigned long chan_read,
+ unsigned long chan_event)
{
int ret;
+ unsigned long channels = chan_read | chan_event;

- if ((data->chan_read | data->chan_event) != (chan_read | chan_event)) {
+ if ((data->chan_read | data->chan_event) != channels) {
ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
SX9310_REG_PROX_CTRL0_SENSOREN_MASK,
- chan_read | chan_event);
+ channels);
if (ret)
return ret;
}
@@ -532,6 +535,7 @@ static void sx9310_push_events(struct iio_dev *indio_dev)
unsigned int val, chan;
struct sx9310_data *data = iio_priv(indio_dev);
s64 timestamp = iio_get_time_ns(indio_dev);
+ unsigned long prox_changed;

/* Read proximity state on all channels */
ret = regmap_read(data->regmap, SX9310_REG_STAT0, &val);
@@ -540,24 +544,23 @@ static void sx9310_push_events(struct iio_dev *indio_dev)
return;
}

- for (chan = 0; chan < SX9310_NUM_CHANNELS; chan++) {
+ /*
+ * Only iterate over channels with changes on proximity status that have
+ * events enabled.
+ */
+ prox_changed = (data->chan_prox_stat ^ val) & data->chan_event;
+
+ for_each_set_bit(chan, &prox_changed, SX9310_NUM_CHANNELS) {
int dir;
u64 ev;
- bool new_prox = val & BIT(chan);
-
- if (!(data->chan_event & BIT(chan)))
- continue;
- if (new_prox == data->prox_stat[chan])
- /* No change on this channel. */
- continue;

- dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
+ dir = val & BIT(chan) ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
IIO_EV_TYPE_THRESH, dir);

iio_push_event(indio_dev, ev, timestamp);
- data->prox_stat[chan] = new_prox;
}
+ data->chan_prox_stat = val;
}

static irqreturn_t sx9310_irq_thread_handler(int irq, void *private)
@@ -714,13 +717,13 @@ static irqreturn_t sx9310_trigger_handler(int irq, void *private)
static int sx9310_buffer_preenable(struct iio_dev *indio_dev)
{
struct sx9310_data *data = iio_priv(indio_dev);
- unsigned int channels = 0;
+ unsigned long channels = 0;
int bit, ret;

mutex_lock(&data->mutex);
for_each_set_bit(bit, indio_dev->active_scan_mask,
indio_dev->masklength)
- channels |= BIT(indio_dev->channels[bit].channel);
+ __set_bit(indio_dev->channels[bit].channel, &channels);

ret = sx9310_update_chan_en(data, channels, data->chan_event);
mutex_unlock(&data->mutex);
--
2.28.0.163.g6104cc2f0b6-goog