[PATCH 19/23] gpio: nomadik: grab optional reset control and deassert it at probe
From: Théo Lebrun <theo.lebrun@bootlin.com>
Date: 2024-02-14 16:25:00
Also in:
linux-arm-kernel, linux-gpio, linux-mips, lkml
Subsystem:
arm/nomadik/ux500 architectures, gpio subsystem, the rest · Maintainers:
Linus Walleij, Bartosz Golaszewski, Linus Torvalds
Fetch a reference to the optional shared reset control and deassert it if it exists. Optional because not all platforms that use this driver have a reset attached to the reset block. Shared because some platforms that use the reset (at least Mobileye EyeQ5) share the reset across banks. Do not keep a reference to the reset control as it is not needed afterwards; the driver does not handle suspend, does not use runtime PM and does not register a remove callback. The operation is done in nmk_gpio_populate_chip(). This function is called by either gpio-nomadik or pinctrl-nomadik, whoever comes first. This is here for historic reasons and could probably be removed now; it seems gpio-ranges enforces the ordering to be pinctrl-first. It is not the topic of the present patch however. Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> --- drivers/gpio/gpio-nomadik.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/drivers/gpio/gpio-nomadik.c b/drivers/gpio/gpio-nomadik.c
index 21bb6d6363fc..b623c093b54d 100644
--- a/drivers/gpio/gpio-nomadik.c
+++ b/drivers/gpio/gpio-nomadik.c@@ -513,12 +513,14 @@ struct nmk_gpio_chip *nmk_gpio_populate_chip(struct device_node *np, { struct nmk_gpio_chip *nmk_chip; struct platform_device *gpio_pdev; + struct reset_control *reset; struct gpio_chip *chip; struct resource *res; struct clk *clk; void __iomem *base; uintptr_t flags; u32 id, ngpio; + int ret; gpio_pdev = of_find_device_by_node(np); if (!gpio_pdev) {
@@ -576,6 +578,19 @@ struct nmk_gpio_chip *nmk_gpio_populate_chip(struct device_node *np, clk_prepare(clk); nmk_chip->clk = clk; + reset = devm_reset_control_get_optional_shared(&gpio_pdev->dev, NULL); + if (IS_ERR(reset)) { + dev_err(&pdev->dev, "failed getting reset control: %ld\n", + PTR_ERR(reset)); + return ERR_CAST(reset); + } + + ret = reset_control_deassert(reset); + if (ret) { + dev_err(&pdev->dev, "failed reset deassert: %d\n", ret); + return ERR_PTR(ret); + } + #ifdef CONFIG_PINCTRL_NOMADIK BUG_ON(nmk_chip->bank >= ARRAY_SIZE(nmk_gpio_chips)); nmk_gpio_chips[id] = nmk_chip;
--
2.43.1