On Mi, 2024-02-14 at 17:24 +0100, Théo Lebrun wrote: > 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. I suppose you don't care that the reset is only ever deasserted once and never asserted again on this hardware, but for shared reset controls the expectation is that deassert/assert calls are balanced: https://docs.kernel.org/driver-api/reset.html?highlight=balanced#assertion-and-deassertion So maybe this warrants a comment in the code. Or do you mean to suppress unbind via suppress_bind_attrs to explain away any missing cleanup? > 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@xxxxxxxxxxx> > --- > 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); Consider using dev_err_probe() here. regards Philipp
