linux-kernel - [RFT PATCH 15/21] arm: omap1: ams-delta: stop using gpiochip

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Message-Id: <20230905185309.131295-16-brgl@bgdev.pl>
Date:   Tue,  5 Sep 2023 20:53:03 +0200
From:   Bartosz Golaszewski <brgl@...ev.pl>
To:     Aaro Koskinen <aaro.koskinen@....fi>,
        Janusz Krzysztofik <jmkrzyszt@...il.com>,
        Tony Lindgren <tony@...mide.com>,
        Russell King <linux@...linux.org.uk>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <brgl@...ev.pl>,
        Dipen Patel <dipenp@...dia.com>,
        Thierry Reding <thierry.reding@...il.com>,
        Jonathan Hunter <jonathanh@...dia.com>,
        Hans de Goede <hdegoede@...hat.com>,
        Mark Gross <markgross@...nel.org>
Cc:     linux-arm-kernel@...ts.infradead.org, linux-omap@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-gpio@...r.kernel.org,
        linux-acpi@...r.kernel.org, timestamp@...ts.linux.dev,
        linux-tegra@...r.kernel.org, platform-driver-x86@...r.kernel.org,
        Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [RFT PATCH 15/21] arm: omap1: ams-delta: stop using gpiochip_find()

From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>

gpiochip_find() is going away as it's not hot-unplug safe. This platform
is not affected by any of the related problems as this GPIO controller
cannot really go away but in order to finally remove this function, we
need to convert it to using gpio_device_find() as well.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 arch/arm/mach-omap1/board-ams-delta.c | 36 +++++++++++++--------------
 1 file changed, 17 insertions(+), 19 deletions(-)

diff --git a/arch/arm/mach-omap1/board-ams-delta.c b/arch/arm/mach-omap1/board-ams-delta.c
index 9808cd27e2cf..a28ea6ac1eba 100644
--- a/arch/arm/mach-omap1/board-ams-delta.c
+++ b/arch/arm/mach-omap1/board-ams-delta.c
@@ -560,22 +560,6 @@ static struct gpiod_lookup_table *ams_delta_gpio_tables[] __initdata = {
 	&ams_delta_nand_gpio_table,
 };
 
-/*
- * Some drivers may not use GPIO lookup tables but need to be provided
- * with GPIO numbers.  The same applies to GPIO based IRQ lines - some
- * drivers may even not use GPIO layer but expect just IRQ numbers.
- * We could either define GPIO lookup tables then use them on behalf
- * of those devices, or we can use GPIO driver level methods for
- * identification of GPIO and IRQ numbers. For the purpose of the latter,
- * defina a helper function which identifies GPIO chips by their labels.
- */
-static int gpiochip_match_by_label(struct gpio_chip *chip, void *data)
-{
-	char *label = data;
-
-	return !strcmp(label, chip->label);
-}
-
 static struct gpiod_hog ams_delta_gpio_hogs[] = {
 	GPIO_HOG(LATCH2_LABEL, LATCH2_PIN_KEYBRD_DATAOUT, "keybrd_dataout",
 		 GPIO_ACTIVE_HIGH, GPIOD_OUT_LOW),
@@ -615,14 +599,28 @@ static void __init modem_assign_irq(struct gpio_chip *chip)
  */
 static void __init omap_gpio_deps_init(void)
 {
+	struct gpio_device *gdev;
 	struct gpio_chip *chip;
 
-	chip = gpiochip_find(OMAP_GPIO_LABEL, gpiochip_match_by_label);
-	if (!chip) {
-		pr_err("%s: OMAP GPIO chip not found\n", __func__);
+	/*
+	 * Some drivers may not use GPIO lookup tables but need to be provided
+	 * with GPIO numbers. The same applies to GPIO based IRQ lines - some
+	 * drivers may even not use GPIO layer but expect just IRQ numbers.
+	 * We could either define GPIO lookup tables then use them on behalf
+	 * of those devices, or we can use GPIO driver level methods for
+	 * identification of GPIO and IRQ numbers.
+	 *
+	 * This reference will be leaked but that's alright as this device
+	 * never goes down.
+	 */
+	gdev = gpio_device_find_by_label(OMAP_GPIO_LABEL);
+	if (!gdev) {
+		pr_err("%s: OMAP GPIO device not found\n", __func__);
 		return;
 	}
 
+	chip = gpio_device_get_chip(gdev);
+
 	/*
 	 * Start with FIQ initialization as it may have to request
 	 * and release successfully each OMAP GPIO pin in turn.
-- 
2.39.2