Some converters require an external signal to start the conversion. This patch
adds support to the bfintmr trigger driver to generate such a signal.
Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
---
drivers/staging/iio/trigger/iio-trig-bfin-timer.c | 72 ++++++++++++++++-----
drivers/staging/iio/trigger/iio-trig-bfin-timer.h | 24 +++++++
2 files changed, 80 insertions(+), 16 deletions(-)
create mode 100644 drivers/staging/iio/trigger/iio-trig-bfin-timer.h
diff --git a/drivers/staging/iio/trigger/iio-trig-bfin-timer.c b/drivers/staging/iio/trigger/iio-trig-bfin-timer.c
index d9d3dc9..52062d7 100644
--- a/drivers/staging/iio/trigger/iio-trig-bfin-timer.c
+++ b/drivers/staging/iio/trigger/iio-trig-bfin-timer.c
@@ -14,14 +14,18 @@
#include <linux/delay.h>
#include <asm/gptimers.h>
+#include <asm/portmux.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
+#include "iio-trig-bfin-timer.h"
+
struct bfin_timer {
unsigned short id, bit;
unsigned long irqbit;
int irq;
+ int pin;
};
/*
@@ -30,22 +34,22 @@ struct bfin_timer {
*/
static struct bfin_timer iio_bfin_timer_code[MAX_BLACKFIN_GPTIMERS] = {
- {TIMER0_id, TIMER0bit, TIMER_STATUS_TIMIL0, IRQ_TIMER0},
- {TIMER1_id, TIMER1bit, TIMER_STATUS_TIMIL1, IRQ_TIMER1},
- {TIMER2_id, TIMER2bit, TIMER_STATUS_TIMIL2, IRQ_TIMER2},
+ {TIMER0_id, TIMER0bit, TIMER_STATUS_TIMIL0, IRQ_TIMER0, P_TMR0},
+ {TIMER1_id, TIMER1bit, TIMER_STATUS_TIMIL1, IRQ_TIMER1, P_TMR1},
+ {TIMER2_id, TIMER2bit, TIMER_STATUS_TIMIL2, IRQ_TIMER2, P_TMR2},
#if (MAX_BLACKFIN_GPTIMERS > 3)
- {TIMER3_id, TIMER3bit, TIMER_STATUS_TIMIL3, IRQ_TIMER3},
- {TIMER4_id, TIMER4bit, TIMER_STATUS_TIMIL4, IRQ_TIMER4},
- {TIMER5_id, TIMER5bit, TIMER_STATUS_TIMIL5, IRQ_TIMER5},
- {TIMER6_id, TIMER6bit, TIMER_STATUS_TIMIL6, IRQ_TIMER6},
- {TIMER7_id, TIMER7bit, TIMER_STATUS_TIMIL7, IRQ_TIMER7},
+ {TIMER3_id, TIMER3bit, TIMER_STATUS_TIMIL3, IRQ_TIMER3, P_TMR3},
+ {TIMER4_id, TIMER4bit, TIMER_STATUS_TIMIL4, IRQ_TIMER4, P_TMR4},
+ {TIMER5_id, TIMER5bit, TIMER_STATUS_TIMIL5, IRQ_TIMER5, P_TMR5},
+ {TIMER6_id, TIMER6bit, TIMER_STATUS_TIMIL6, IRQ_TIMER6, P_TMR6},
+ {TIMER7_id, TIMER7bit, TIMER_STATUS_TIMIL7, IRQ_TIMER7, P_TMR7},
#endif
#if (MAX_BLACKFIN_GPTIMERS > 8)
- {TIMER8_id, TIMER8bit, TIMER_STATUS_TIMIL8, IRQ_TIMER8},
- {TIMER9_id, TIMER9bit, TIMER_STATUS_TIMIL9, IRQ_TIMER9},
- {TIMER10_id, TIMER10bit, TIMER_STATUS_TIMIL10, IRQ_TIMER10},
+ {TIMER8_id, TIMER8bit, TIMER_STATUS_TIMIL8, IRQ_TIMER8, P_TMR8},
+ {TIMER9_id, TIMER9bit, TIMER_STATUS_TIMIL9, IRQ_TIMER9, P_TMR9},
+ {TIMER10_id, TIMER10bit, TIMER_STATUS_TIMIL10, IRQ_TIMER10, P_TMR10},
#if (MAX_BLACKFIN_GPTIMERS > 11)
- {TIMER11_id, TIMER11bit, TIMER_STATUS_TIMIL11, IRQ_TIMER11},
+ {TIMER11_id, TIMER11bit, TIMER_STATUS_TIMIL11, IRQ_TIMER11, P_TMR11},
#endif
#endif
};
@@ -54,6 +58,8 @@ struct bfin_tmr_state {
struct iio_trigger *trig;
struct bfin_timer *t;
unsigned timer_num;
+ bool output_enable;
+ unsigned int duty;
int irq;
};
@@ -77,7 +83,7 @@ static ssize_t iio_bfin_tmr_frequency_store(struct device *dev,
{
struct iio_trigger *trig = to_iio_trigger(dev);
struct bfin_tmr_state *st = trig->private_data;
- long val;
+ unsigned long val;
bool enabled;
int ret;
@@ -99,13 +105,13 @@ static ssize_t iio_bfin_tmr_frequency_store(struct device *dev,
goto error_ret;
val = get_sclk() / val;
- if (val <= 4) {
+ if (val <= 4 || val <= st->duty) {
ret = -EINVAL;
goto error_ret;
}
set_gptimer_period(st->t->id, val);
- set_gptimer_pwidth(st->t->id, 1);
+ set_gptimer_pwidth(st->t->id, val - st->duty);
if (enabled)
enable_gptimers(st->t->bit);
@@ -176,7 +182,9 @@ static const struct iio_trigger_ops iio_bfin_tmr_trigger_ops = {
static int __devinit iio_bfin_tmr_trigger_probe(struct platform_device *pdev)
{
+ struct iio_bfin_timer_trigger_pdata *pdata = pdev->dev.platform_data;
struct bfin_tmr_state *st;
+ unsigned int config;
int ret;
st = kzalloc(sizeof(*st), GFP_KERNEL);
@@ -220,13 +228,43 @@ static int __devinit iio_bfin_tmr_trigger_probe(struct platform_device *pdev)
goto out4;
}
- set_gptimer_config(st->t->id, OUT_DIS | PWM_OUT | PERIOD_CNT | IRQ_ENA);
+ config = PWM_OUT | PERIOD_CNT | IRQ_ENA;
+
+ if (pdata && pdata->output_enable) {
+ unsigned long long val;
+
+ st->output_enable = true;
+
+ ret = peripheral_request(st->t->pin, st->trig->name);
+ if (ret)
+ goto out_free_irq;
+
+ val = (unsigned long long)get_sclk() * pdata->duty_ns;
+ do_div(val, NSEC_PER_SEC);
+ st->duty = val;
+
+ /**
+ * The interrupt will be generated at the end of the period,
+ * since we want the interrupt to be generated at end of the
+ * pulse we invert both polarity and duty cycle, so that the
+ * pulse will be generated directly before the interrupt.
+ */
+ if (pdata->active_low)
+ config |= PULSE_HI;
+ } else {
+ st->duty = 1;
+ config |= OUT_DIS;
+ }
+
+ set_gptimer_config(st->t->id, config);
dev_info(&pdev->dev, "iio trigger Blackfin TMR%d, IRQ-%d",
st->timer_num, st->irq);
platform_set_drvdata(pdev, st);
return 0;
+out_free_irq:
+ free_irq(st->irq, st);
out4:
iio_trigger_unregister(st->trig);
out2:
@@ -242,6 +280,8 @@ static int __devexit iio_bfin_tmr_trigger_remove(struct platform_device *pdev)
struct bfin_tmr_state *st = platform_get_drvdata(pdev);
disable_gptimers(st->t->bit);
+ if (st->output_enable)
+ peripheral_free(st->t->pin);
free_irq(st->irq, st);
iio_trigger_unregister(st->trig);
iio_trigger_put(st->trig);
diff --git a/drivers/staging/iio/trigger/iio-trig-bfin-timer.h b/drivers/staging/iio/trigger/iio-trig-bfin-timer.h
new file mode 100644
index 0000000..c07321f
--- /dev/null
+++ b/drivers/staging/iio/trigger/iio-trig-bfin-timer.h
@@ -0,0 +1,24 @@
+#ifndef __IIO_BFIN_TIMER_TRIGGER_H__
+#define __IIO_BFIN_TIMER_TRIGGER_H__
+
+/**
+ * struct iio_bfin_timer_trigger_pdata - timer trigger platform data
+ * @output_enable: Enable external trigger pulse generation.
+ * @active_low: Whether the trigger pulse is active low.
+ * @duty_ns: Length of the trigger pulse in nanoseconds.
+ *
+ * This struct is used to configure the output pulse generation of the blackfin
+ * timer trigger. If output_enable is set to true an external trigger signal
+ * will generated on the pin corresponding to the timer. This is useful for
+ * converters which needs an external signal to start conversion. active_low and
+ * duty_ns are used to configure the type of the trigger pulse. If output_enable
+ * is set to false no external trigger pulse will be generated and active_low
+ * and duty_ns are ignored.
+ **/
+struct iio_bfin_timer_trigger_pdata {
+ bool output_enable;
+ bool active_low;
+ unsigned int duty_ns;
+};
+
+#endif
--
1.7.10.4
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