mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Ahmad Fatoum <a.fatoum@pengutronix.de>
To: barebox@lists.infradead.org
Cc: Ahmad Fatoum <a.fatoum@pengutronix.de>
Subject: [PATCH v2] gpio: iopoll: implement gpio_poll_timeout_us
Date: Mon,  9 Sep 2019 10:14:44 +0200	[thread overview]
Message-ID: <20190909081444.31077-1-a.fatoum@pengutronix.de> (raw)

Sometimes we need to wait for state change on a GPIO, provide a helper
for future code to do this.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
v1 -> v2:
	Add comment describing use of macro
---
 include/gpio.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/include/gpio.h b/include/gpio.h
index 38d6ba2df913..867f3d1dbdc6 100644
--- a/include/gpio.h
+++ b/include/gpio.h
@@ -3,6 +3,7 @@
 
 #include <linux/types.h>
 #include <linux/list.h>
+#include <linux/iopoll.h>
 
 #ifdef CONFIG_GENERIC_GPIO
 void gpio_set_value(unsigned gpio, int value);
@@ -31,6 +32,21 @@ static inline int gpio_direction_input(unsigned gpio)
 void gpio_set_active(unsigned gpio, bool state);
 int gpio_is_active(unsigned gpio);
 int gpio_direction_active(unsigned gpio, bool state);
+
+/**
+ * gpio_poll_timeout_us - Poll till GPIO reaches requested active state
+ * @gpio: gpio to poll
+ * @active: wait till GPIO is active if true, wait till it's inactive if false
+ * @timeout_us: timeout in microseconds
+ *
+ * During the wait barebox pollers are called, if any.
+ */
+#define gpio_poll_timeout_us(gpio, active, timeout_us)			\
+	({								\
+		int __state;						\
+		readx_poll_timeout(gpio_is_active, gpio, __state,	\
+				   __state == (active), timeout_us);	\
+	})
 #else
 static inline void gpio_set_active(unsigned gpio, int value)
 {
@@ -43,6 +59,8 @@ static inline int gpio_direction_active(unsigned gpio, int value)
 {
 	return -EINVAL;
 }
+
+#define gpio_poll_timeout_us(gpio, val, timeout_us) (-ENOSYS)
 #endif
 
 #define ARCH_NR_GPIOS 256
-- 
2.23.0


_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

             reply	other threads:[~2019-09-09  8:14 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-09  8:14 Ahmad Fatoum [this message]
2019-09-09  9:00 ` Sascha Hauer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190909081444.31077-1-a.fatoum@pengutronix.de \
    --to=a.fatoum@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox