From 8d74c3dc8f99d9867254004ed49508c13295cacd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Th=C3=A9o=20Lebrun?= Date: Wed, 28 Feb 2024 12:28:20 +0100 Subject: [PATCH] gpio: nomadik: support shared GPIO IRQs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Support a single IRQs used by multiple GPIO banks. Change the IRQ handler type from a chained handler (as used by gpiolib for ->parent_handler) to a threaded IRQ. Use the generic_handle_domain_irq_safe() helper. The non-safe version must be called in a no-IRQ context. The Mobileye EyeQ5 platform uses this GPIO controller and share an IRQ for its two banks. Signed-off-by: Théo Lebrun Link: https://lore.kernel.org/r/20240228-mbly-gpio-v2-22-3ba757474006@bootlin.com Signed-off-by: Linus Walleij --- drivers/gpio/gpio-nomadik.c | 68 ++++++++++++++++++++----------------- 1 file changed, 36 insertions(+), 32 deletions(-) diff --git a/drivers/gpio/gpio-nomadik.c b/drivers/gpio/gpio-nomadik.c index c22a0864ca70..ca5c28965224 100644 --- a/drivers/gpio/gpio-nomadik.c +++ b/drivers/gpio/gpio-nomadik.c @@ -255,27 +255,28 @@ static void nmk_gpio_irq_shutdown(struct irq_data *d) clk_disable(nmk_chip->clk); } -static void nmk_gpio_irq_handler(struct irq_desc *desc) +static irqreturn_t nmk_gpio_irq_handler(int irq, void *dev_id) { - struct irq_chip *host_chip = irq_desc_get_chip(desc); - struct gpio_chip *chip = irq_desc_get_handler_data(desc); - struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip); - u32 status; - - chained_irq_enter(host_chip, desc); + struct nmk_gpio_chip *nmk_chip = dev_id; + struct gpio_chip *chip = &nmk_chip->chip; + unsigned long mask = GENMASK(chip->ngpio - 1, 0); + unsigned long status; + int bit; clk_enable(nmk_chip->clk); + status = readl(nmk_chip->addr + NMK_GPIO_IS); + + /* Ensure we cannot leave pending bits; this should never occur. */ + if (unlikely(status & ~mask)) + writel(status & ~mask, nmk_chip->addr + NMK_GPIO_IC); + clk_disable(nmk_chip->clk); - while (status) { - int bit = __ffs(status); + for_each_set_bit(bit, &status, chip->ngpio) + generic_handle_domain_irq_safe(chip->irq.domain, bit); - generic_handle_domain_irq(chip->irq.domain, bit); - status &= ~BIT(bit); - } - - chained_irq_exit(host_chip, desc); + return IRQ_RETVAL((status & mask) != 0); } /* I/O Functions */ @@ -568,19 +569,20 @@ static const struct irq_chip nmk_irq_chip = { GPIOCHIP_IRQ_RESOURCE_HELPERS, }; -static int nmk_gpio_probe(struct platform_device *dev) +static int nmk_gpio_probe(struct platform_device *pdev) { - struct device_node *np = dev->dev.of_node; + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; struct nmk_gpio_chip *nmk_chip; - struct gpio_chip *chip; struct gpio_irq_chip *girq; bool supports_sleepmode; + struct gpio_chip *chip; int irq; int ret; - nmk_chip = nmk_gpio_populate_chip(np, dev); + nmk_chip = nmk_gpio_populate_chip(np, pdev); if (IS_ERR(nmk_chip)) { - dev_err(&dev->dev, "could not populate nmk chip struct\n"); + dev_err(dev, "could not populate nmk chip struct\n"); return PTR_ERR(nmk_chip); } @@ -588,9 +590,9 @@ static int nmk_gpio_probe(struct platform_device *dev) device_property_read_bool(dev, "st,supports-sleepmode"); /* Correct platform device ID */ - dev->id = nmk_chip->bank; + pdev->id = nmk_chip->bank; - irq = platform_get_irq(dev, 0); + irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; @@ -602,7 +604,7 @@ static int nmk_gpio_probe(struct platform_device *dev) spin_lock_init(&nmk_chip->lock); chip = &nmk_chip->chip; - chip->parent = &dev->dev; + chip->parent = dev; chip->request = gpiochip_generic_request; chip->free = gpiochip_generic_free; chip->get_direction = nmk_gpio_get_dir; @@ -616,17 +618,19 @@ static int nmk_gpio_probe(struct platform_device *dev) girq = &chip->irq; gpio_irq_chip_set_chip(girq, &nmk_irq_chip); - girq->parent_handler = nmk_gpio_irq_handler; - girq->num_parents = 1; - girq->parents = devm_kcalloc(&dev->dev, 1, - sizeof(*girq->parents), - GFP_KERNEL); - if (!girq->parents) - return -ENOMEM; - girq->parents[0] = irq; + girq->parent_handler = NULL; + girq->num_parents = 0; + girq->parents = NULL; girq->default_type = IRQ_TYPE_NONE; girq->handler = handle_edge_irq; + ret = devm_request_irq(dev, irq, nmk_gpio_irq_handler, IRQF_SHARED, + dev_name(dev), nmk_chip); + if (ret) { + dev_err(dev, "failed requesting IRQ\n"); + return ret; + } + clk_enable(nmk_chip->clk); nmk_chip->lowemi = readl_relaxed(nmk_chip->addr + NMK_GPIO_LOWEMI); clk_disable(nmk_chip->clk); @@ -635,9 +639,9 @@ static int nmk_gpio_probe(struct platform_device *dev) if (ret) return ret; - platform_set_drvdata(dev, nmk_chip); + platform_set_drvdata(pdev, nmk_chip); - dev_info(&dev->dev, "chip registered\n"); + dev_info(dev, "chip registered\n"); return 0; }