From 2aecc5b95cdb17d7b80463e9c1a542f389403cbb Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Mon, 17 Sep 2012 13:26:00 +0100 Subject: [PATCH] staging:iio:trigger:bfintmr: Only enable timer when necessary This patch hooks up the set_trigger_state callback for the blackfin timer trigger driver and only enables the timer when a trigger consumer requests it to be enabled. There really is no reason to keep the timer running and generate interrupts if nobody is listening to them. Signed-off-by: Lars-Peter Clausen Signed-off-by: Jonathan Cameron --- .../staging/iio/trigger/iio-trig-bfin-timer.c | 27 ++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) diff --git a/drivers/staging/iio/trigger/iio-trig-bfin-timer.c b/drivers/staging/iio/trigger/iio-trig-bfin-timer.c index 2772ea2fb0dc..d9d3dc98885c 100644 --- a/drivers/staging/iio/trigger/iio-trig-bfin-timer.c +++ b/drivers/staging/iio/trigger/iio-trig-bfin-timer.c @@ -57,12 +57,28 @@ struct bfin_tmr_state { int irq; }; +static int iio_bfin_tmr_set_state(struct iio_trigger *trig, bool state) +{ + struct bfin_tmr_state *st = trig->private_data; + + if (get_gptimer_period(st->t->id) == 0) + return -EINVAL; + + if (state) + enable_gptimers(st->t->bit); + else + disable_gptimers(st->t->bit); + + return 0; +} + static ssize_t iio_bfin_tmr_frequency_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct iio_trigger *trig = to_iio_trigger(dev); struct bfin_tmr_state *st = trig->private_data; long val; + bool enabled; int ret; ret = strict_strtoul(buf, 10, &val); @@ -74,7 +90,10 @@ static ssize_t iio_bfin_tmr_frequency_store(struct device *dev, goto error_ret; } - disable_gptimers(st->t->bit); + enabled = get_enabled_gptimers() & st->t->bit; + + if (enabled) + disable_gptimers(st->t->bit); if (!val) goto error_ret; @@ -87,7 +106,9 @@ static ssize_t iio_bfin_tmr_frequency_store(struct device *dev, set_gptimer_period(st->t->id, val); set_gptimer_pwidth(st->t->id, 1); - enable_gptimers(st->t->bit); + + if (enabled) + enable_gptimers(st->t->bit); error_ret: return ret ? ret : count; @@ -127,7 +148,6 @@ static const struct attribute_group *iio_bfin_tmr_trigger_attr_groups[] = { NULL }; - static irqreturn_t iio_bfin_tmr_trigger_isr(int irq, void *devid) { struct bfin_tmr_state *st = devid; @@ -151,6 +171,7 @@ static int iio_bfin_tmr_get_number(int irq) static const struct iio_trigger_ops iio_bfin_tmr_trigger_ops = { .owner = THIS_MODULE, + .set_trigger_state = iio_bfin_tmr_set_state, }; static int __devinit iio_bfin_tmr_trigger_probe(struct platform_device *pdev) -- 2.20.1