From 2cba05451a6d0c703bb74f1a250691404f27c4f1 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Mon, 31 Jan 2022 11:35:53 +0100
Subject: [PATCH] gpio: aggregator: Fix calling into sleeping GPIO controllers
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Git-commit: 2cba05451a6d0c703bb74f1a250691404f27c4f1
Patch-mainline: v5.17-rc4
References: git-fixes

If the parent GPIO controller is a sleeping controller (e.g. a GPIO
controller connected to I2C), getting or setting a GPIO triggers a
might_sleep() warning.  This happens because the GPIO Aggregator takes
the can_sleep flag into account only for its internal locking, not for
calling into the parent GPIO controller.

Fix this by using the gpiod_[gs]et*_cansleep() APIs when calling into a
sleeping GPIO controller.

Reported-by: Mikko Salomäki <ms@datarespons.se>
Fixes: 828546e24280f721 ("gpio: Add GPIO Aggregator")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpio/gpio-aggregator.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
index 869dc952cf45..0cb2664085cf 100644
--- a/drivers/gpio/gpio-aggregator.c
+++ b/drivers/gpio/gpio-aggregator.c
@@ -278,7 +278,8 @@ static int gpio_fwd_get(struct gpio_chip *chip, unsigned int offset)
 {
 	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 
-	return gpiod_get_value(fwd->descs[offset]);
+	return chip->can_sleep ? gpiod_get_value_cansleep(fwd->descs[offset])
+			       : gpiod_get_value(fwd->descs[offset]);
 }
 
 static int gpio_fwd_get_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
@@ -293,7 +294,10 @@ static int gpio_fwd_get_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
 	for_each_set_bit(i, mask, fwd->chip.ngpio)
 		descs[j++] = fwd->descs[i];
 
-	error = gpiod_get_array_value(j, descs, NULL, values);
+	if (fwd->chip.can_sleep)
+		error = gpiod_get_array_value_cansleep(j, descs, NULL, values);
+	else
+		error = gpiod_get_array_value(j, descs, NULL, values);
 	if (error)
 		return error;
 
@@ -328,7 +332,10 @@ static void gpio_fwd_set(struct gpio_chip *chip, unsigned int offset, int value)
 {
 	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 
-	gpiod_set_value(fwd->descs[offset], value);
+	if (chip->can_sleep)
+		gpiod_set_value_cansleep(fwd->descs[offset], value);
+	else
+		gpiod_set_value(fwd->descs[offset], value);
 }
 
 static void gpio_fwd_set_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
@@ -343,7 +350,10 @@ static void gpio_fwd_set_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
 		descs[j++] = fwd->descs[i];
 	}
 
-	gpiod_set_array_value(j, descs, NULL, values);
+	if (fwd->chip.can_sleep)
+		gpiod_set_array_value_cansleep(j, descs, NULL, values);
+	else
+		gpiod_set_array_value(j, descs, NULL, values);
 }
 
 static void gpio_fwd_set_multiple_locked(struct gpio_chip *chip,
-- 
2.31.1