From: Janusz Krzysztofik <jmkrzyszt@gmail.com>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: Boris Brezillon <boris.brezillon@bootlin.com>,
linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
Janusz Krzysztofik <jmkrzyszt@gmail.com>
Subject: [PATCH] gpiolib: Defer on non-DT find_chip_by_name() failure
Date: Tue, 3 Jul 2018 19:26:35 +0200 [thread overview]
Message-ID: <20180703172635.32508-1-jmkrzyszt@gmail.com> (raw)
Avoid replication of error code conversion in non-DT GPIO consumers'
code by returning -EPROBE_DEFER from gpiod_find() in case a chip
identified by its label in a registered lookup table is not ready.
See https://lkml.org/lkml/2018/5/30/176 for example case.
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
---
If accepted, please add
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
if Boris doesn't mind.
Thanks,
Janusz
drivers/gpio/gpiolib.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index e11a3bb03820..15dc77c80328 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -3639,9 +3639,16 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
chip = find_chip_by_name(p->chip_label);
if (!chip) {
- dev_err(dev, "cannot find GPIO chip %s\n",
- p->chip_label);
- return ERR_PTR(-ENODEV);
+ /*
+ * As the lookup table indicates a chip with
+ * p->chip_label should exist, assume it may
+ * still appear latar and let the interested
+ * consumer be probed again or let the Deferred
+ * Probe infrastructure handle the error.
+ */
+ dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
+ p->chip_label);
+ return ERR_PTR(-EPROBE_DEFER);
}
if (chip->ngpio <= p->chip_hwnum) {
--
2.16.4
next reply other threads:[~2018-07-03 17:26 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-03 17:26 Janusz Krzysztofik [this message]
2018-07-03 17:31 ` [PATCH] gpiolib: Defer on non-DT find_chip_by_name() failure Boris Brezillon
2018-07-04 19:13 ` Janusz Krzysztofik
2018-07-05 5:23 ` Uwe Kleine-König
2018-07-05 5:50 ` Lee Jones
2018-07-05 20:56 ` Janusz Krzysztofik
2018-07-06 6:06 ` Lee Jones
2018-07-06 9:03 ` Richard Fitzgerald
2018-07-06 18:58 ` Janusz Krzysztofik
2018-07-03 20:06 ` Andy Shevchenko
2018-07-03 22:18 ` [PATCH v2] " Janusz Krzysztofik
2018-07-04 7:17 ` Boris Brezillon
2018-07-09 13:18 ` Linus Walleij
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