linux-kernel - [PATCH v3 08/10] gpiolib: of: factor out code overriding gpio line polarity

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Message-Id: <20221011-gpiolib-quirks-v3-8-eae9cc2ed0a1@gmail.com>
Date:   Mon, 17 Oct 2022 22:41:09 -0700
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Bartosz Golaszewski <brgl@...ev.pl>,
        Linus Walleij <linus.walleij@...aro.org>
Cc:     Alexander Stein <alexander.stein@...tq-group.com>,
        linux-arm-kernel@...ts.infradead.org, linux-gpio@...r.kernel.org,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Daniel Thompson <daniel.thompson@...aro.org>,
        linux-kernel@...r.kernel.org, linux-mediatek@...ts.infradead.org
Subject: [PATCH v3 08/10] gpiolib: of: factor out code overriding gpio line polarity

There are several instances where we use a separate property to
override polarity specified in gpio property. Factor it out into
a separate function.

Reviewed-by: Linus Walleij <linus.walleij@...aro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
---
 drivers/gpio/gpiolib-of.c | 48 +++++++++++++++++++++++++++--------------------
 1 file changed, 28 insertions(+), 20 deletions(-)

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index d22498c72a67..6faf0dc7bc31 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -130,6 +130,28 @@ bool of_gpio_need_valid_mask(const struct gpio_chip *gc)
 	return false;
 }
 
+/*
+ * Overrides stated polarity of a gpio line and warns when there is a
+ * discrepancy.
+ */
+static void of_gpio_quirk_polarity(const struct device_node *np,
+				   bool active_high,
+				   enum of_gpio_flags *flags)
+{
+	if (active_high) {
+		if (*flags & OF_GPIO_ACTIVE_LOW) {
+			pr_warn("%s GPIO handle specifies active low - ignored\n",
+				of_node_full_name(np));
+			*flags &= ~OF_GPIO_ACTIVE_LOW;
+		}
+	} else {
+		if (!(*flags & OF_GPIO_ACTIVE_LOW))
+			pr_info("%s enforce active low on GPIO handle\n",
+				of_node_full_name(np));
+		*flags |= OF_GPIO_ACTIVE_LOW;
+	}
+}
+
 static void of_gpio_flags_quirks(const struct device_node *np,
 				 const char *propname,
 				 enum of_gpio_flags *flags,
@@ -145,7 +167,7 @@ static void of_gpio_flags_quirks(const struct device_node *np,
 	     (!(strcmp(propname, "enable-gpio") &&
 		strcmp(propname, "enable-gpios")) &&
 	      of_device_is_compatible(np, "regulator-gpio")))) {
-		bool active_low = !of_property_read_bool(np,
+		bool active_high = of_property_read_bool(np,
 							 "enable-active-high");
 		/*
 		 * The regulator GPIO handles are specified such that the
@@ -153,13 +175,7 @@ static void of_gpio_flags_quirks(const struct device_node *np,
 		 * the polarity of the GPIO line. Any phandle flags must
 		 * be actively ignored.
 		 */
-		if ((*flags & OF_GPIO_ACTIVE_LOW) && !active_low) {
-			pr_warn("%s GPIO handle specifies active low - ignored\n",
-				of_node_full_name(np));
-			*flags &= ~OF_GPIO_ACTIVE_LOW;
-		}
-		if (active_low)
-			*flags |= OF_GPIO_ACTIVE_LOW;
+		of_gpio_quirk_polarity(np, active_high, flags);
 	}
 	/*
 	 * Legacy open drain handling for fixed voltage regulators.
@@ -200,18 +216,10 @@ static void of_gpio_flags_quirks(const struct device_node *np,
 				 * conflict and the "spi-cs-high" flag will
 				 * take precedence.
 				 */
-				if (of_property_read_bool(child, "spi-cs-high")) {
-					if (*flags & OF_GPIO_ACTIVE_LOW) {
-						pr_warn("%s GPIO handle specifies active low - ignored\n",
-							of_node_full_name(child));
-						*flags &= ~OF_GPIO_ACTIVE_LOW;
-					}
-				} else {
-					if (!(*flags & OF_GPIO_ACTIVE_LOW))
-						pr_info("%s enforce active low on chipselect handle\n",
-							of_node_full_name(child));
-					*flags |= OF_GPIO_ACTIVE_LOW;
-				}
+				bool active_high = of_property_read_bool(child,
+								"spi-cs-high");
+				of_gpio_quirk_polarity(child, active_high,
+						       flags);
 				of_node_put(child);
 				break;
 			}

-- 
b4 0.11.0-dev-5166b