pwm: Implement tracing for .get_state() and .apply_state()

This allows to log all calls to the driver's lowlevel functions which
simplifies debugging in some cases.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Uwe Kleine-König 2019-10-24 10:08:29 +02:00 committed by Thierry Reding
parent af4fab8bed
commit 1188829abc
2 changed files with 66 additions and 1 deletions

View File

@ -20,6 +20,9 @@
#include <dt-bindings/pwm/pwm.h>
#define CREATE_TRACE_POINTS
#include <trace/events/pwm.h>
#define MAX_PWMS 1024
static DEFINE_MUTEX(pwm_lookup_lock);
@ -114,8 +117,10 @@ static int pwm_device_request(struct pwm_device *pwm, const char *label)
}
}
if (pwm->chip->ops->get_state)
if (pwm->chip->ops->get_state) {
pwm->chip->ops->get_state(pwm->chip, pwm, &pwm->state);
trace_pwm_get(pwm, &pwm->state);
}
set_bit(PWMF_REQUESTED, &pwm->flags);
pwm->label = label;
@ -472,6 +477,8 @@ int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
if (err)
return err;
trace_pwm_apply(pwm, state);
pwm->state = *state;
} else {
/*

View File

@ -0,0 +1,58 @@
/* SPDX-License-Identifier: GPL-2.0-or-later */
#undef TRACE_SYSTEM
#define TRACE_SYSTEM pwm
#if !defined(_TRACE_PWM_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_PWM_H
#include <linux/pwm.h>
#include <linux/tracepoint.h>
DECLARE_EVENT_CLASS(pwm,
TP_PROTO(struct pwm_device *pwm, const struct pwm_state *state),
TP_ARGS(pwm, state),
TP_STRUCT__entry(
__field(struct pwm_device *, pwm)
__field(u64, period)
__field(u64, duty_cycle)
__field(enum pwm_polarity, polarity)
__field(bool, enabled)
),
TP_fast_assign(
__entry->pwm = pwm;
__entry->period = state->period;
__entry->duty_cycle = state->duty_cycle;
__entry->polarity = state->polarity;
__entry->enabled = state->enabled;
),
TP_printk("%p: period=%llu duty_cycle=%llu polarity=%d enabled=%d",
__entry->pwm, __entry->period, __entry->duty_cycle,
__entry->polarity, __entry->enabled)
);
DEFINE_EVENT(pwm, pwm_apply,
TP_PROTO(struct pwm_device *pwm, const struct pwm_state *state),
TP_ARGS(pwm, state)
);
DEFINE_EVENT(pwm, pwm_get,
TP_PROTO(struct pwm_device *pwm, const struct pwm_state *state),
TP_ARGS(pwm, state)
);
#endif /* _TRACE_PWM_H */
/* This part must be outside protection */
#include <trace/define_trace.h>