patches.renesas/0050-gpio-rcar-Fine-grained-Runtime-PM-support.patch

From 4486d679f997a2f6e9217aebdf2fce73df96f975 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Thu, 8 Dec 2016 18:32:28 +0100
Subject: [PATCH 050/255] gpio: rcar: Fine-grained Runtime PM support
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Currently gpio modules are runtime-resumed at probe time. This means the
gpio module will be active all the time (except during system suspend,
if not configured as a wake-up source).

While an R-Car Gen2 gpio module retains pins configured for output at
the requested level while put in standby mode, gpio register cannot be
accessed while suspended.  Unfortunately pm_runtime_get_sync() cannot be
called from all contexts where gpio register access is needed. Hence
move the Runtime PM handling from probe/remove time to gpio request/free
time, which is probably the best we can do.

On r8a7791/koelsch, gpio modules 0, 1, 3, and 4 are now suspended during
normal use (gpio2 is used for LEDs and regulators, gpio5 for keys, gpio6
for SD-Card CD & WP, gpio7 for keys and regulators).

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[Niklas: s/gpio_to_priv(chip)/gpiochip_get_data(chip)/]
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

(cherry picked from commit 2d65472bcb3f2e1f305529655bb06054dc9e2804)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
---
 drivers/gpio/gpio-rcar.c |   20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

--- a/drivers/gpio/gpio-rcar.c
+++ b/drivers/gpio/gpio-rcar.c
@@ -242,11 +242,24 @@ static void gpio_rcar_config_general_inp
 
 static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset)
 {
-	return pinctrl_request_gpio(chip->base + offset);
+	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
+	int error;
+
+	error = pm_runtime_get_sync(&p->pdev->dev);
+	if (error < 0)
+		return error;
+
+	error = pinctrl_request_gpio(chip->base + offset);
+	if (error)
+		pm_runtime_put(&p->pdev->dev);
+
+	return error;
 }
 
 static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset)
 {
+	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
+
 	pinctrl_free_gpio(chip->base + offset);
 
 	/*
@@ -254,6 +267,8 @@ static void gpio_rcar_free(struct gpio_c
 	 * drive the GPIO pin as an output.
 	 */
 	gpio_rcar_config_general_input_output_mode(chip, offset, false);
+
+	pm_runtime_put(&p->pdev->dev);
 }
 
 static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset)
@@ -426,7 +441,6 @@ static int gpio_rcar_probe(struct platfo
 	}
 
 	pm_runtime_enable(dev);
-	pm_runtime_get_sync(dev);
 
 	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
@@ -495,7 +509,6 @@ static int gpio_rcar_probe(struct platfo
 err1:
 	gpiochip_remove(gpio_chip);
 err0:
-	pm_runtime_put(dev);
 	pm_runtime_disable(dev);
 	return ret;
 }
@@ -506,7 +519,6 @@ static int gpio_rcar_remove(struct platf
 
 	gpiochip_remove(&p->gpio_chip);
 
-	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	return 0;
 }