[PATCH 5/5] gpio: tegra186: Make the irqchip immutable

From: Marc Zyngier <maz@kernel.org>
To: linux-kernel@vger.kernel.org
Cc: Linus Walleij <linus.walleij@linaro.org>,
	Bartosz Golaszewski <brgl@bgdev.pl>,
	Thierry Reding <thierry.reding@gmail.com>,
	Joey Gouly <joey.gouly@arm.com>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Hector Martin <marcan@marcan.st>, Sven Peter <sven@svenpeter.dev>,
	Alyssa Rosenzweig <alyssa@rosenzweig.io>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Andy Gross <agross@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-gpio@vger.kernel.org, linux-tegra@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-arm-msm@vger.kernel.org, kernel-team@android.com
Subject: [PATCH 5/5] gpio: tegra186: Make the irqchip immutable
Date: Wed, 23 Feb 2022 15:44:05 +0000	[thread overview]
Message-ID: <20220223154405.54912-6-maz@kernel.org> (raw)
In-Reply-To: <20220223154405.54912-1-maz@kernel.org>

Prevent gpiolib from messing with the irqchip by advertising
the irq_chip structure as immutable, making it const, and adding
the various calls that gpiolib relies upon.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/gpio/gpio-tegra186.c | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c
index 8d298beffd86..2455e1a2c451 100644
--- a/drivers/gpio/gpio-tegra186.c
+++ b/drivers/gpio/gpio-tegra186.c
@@ -80,7 +80,6 @@ struct tegra_gpio_soc {
 
 struct tegra_gpio {
 	struct gpio_chip gpio;
-	struct irq_chip intc;
 	unsigned int num_irq;
 	unsigned int *irq;
 
@@ -372,6 +371,8 @@ static void tegra186_irq_mask(struct irq_data *data)
 	value = readl(base + TEGRA186_GPIO_ENABLE_CONFIG);
 	value &= ~TEGRA186_GPIO_ENABLE_CONFIG_INTERRUPT;
 	writel(value, base + TEGRA186_GPIO_ENABLE_CONFIG);
+
+	gpiochip_disable_irq(&gpio->gpio, data->hwirq);
 }
 
 static void tegra186_irq_unmask(struct irq_data *data)
@@ -385,6 +386,8 @@ static void tegra186_irq_unmask(struct irq_data *data)
 	if (WARN_ON(base == NULL))
 		return;
 
+	gpiochip_enable_irq(&gpio->gpio, data->hwirq);
+
 	value = readl(base + TEGRA186_GPIO_ENABLE_CONFIG);
 	value |= TEGRA186_GPIO_ENABLE_CONFIG_INTERRUPT;
 	writel(value, base + TEGRA186_GPIO_ENABLE_CONFIG);
@@ -456,6 +459,25 @@ static int tegra186_irq_set_wake(struct irq_data *data, unsigned int on)
 	return 0;
 }
 
+static void tegra186_irq_print_chip(struct irq_data *data, struct seq_file *p)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+
+	seq_printf(p, dev_name(gc->parent));
+}
+
+static const struct irq_chip tegra186_gpio_irq_chip = {
+	.irq_request_resources	= gpiochip_irq_reqres,
+	.irq_release_resources	= gpiochip_irq_relres,
+	.irq_ack		= tegra186_irq_ack,
+	.irq_mask		= tegra186_irq_mask,
+	.irq_unmask		= tegra186_irq_unmask,
+	.irq_set_type		= tegra186_irq_set_type,
+	.irq_set_wake		= tegra186_irq_set_wake,
+	.irq_print_chip		= tegra186_irq_print_chip,
+	.flags			= IRQCHIP_IMMUTABLE,
+};
+
 static void tegra186_gpio_irq(struct irq_desc *desc)
 {
 	struct tegra_gpio *gpio = irq_desc_get_handler_data(desc);
@@ -760,15 +782,8 @@ static int tegra186_gpio_probe(struct platform_device *pdev)
 	gpio->gpio.of_xlate = tegra186_gpio_of_xlate;
 #endif /* CONFIG_OF_GPIO */
 
-	gpio->intc.name = dev_name(&pdev->dev);
-	gpio->intc.irq_ack = tegra186_irq_ack;
-	gpio->intc.irq_mask = tegra186_irq_mask;
-	gpio->intc.irq_unmask = tegra186_irq_unmask;
-	gpio->intc.irq_set_type = tegra186_irq_set_type;
-	gpio->intc.irq_set_wake = tegra186_irq_set_wake;
-
 	irq = &gpio->gpio.irq;
-	irq->chip = &gpio->intc;
+	irq->chip = (struct irq_chip *)&tegra186_gpio_irq_chip;
 	irq->fwnode = of_node_to_fwnode(pdev->dev.of_node);
 	irq->child_to_parent_hwirq = tegra186_gpio_child_to_parent_hwirq;
 	irq->populate_parent_alloc_arg = tegra186_gpio_populate_parent_fwspec;
-- 
2.30.2

