Hello Russell, On Sun, Mar 29, 2020 at 02:34:00PM +0100, Russell King - ARM Linux admin wrote: > On Sun, Mar 29, 2020 at 03:16:59PM +0200, Uwe Kleine-König wrote: > > On Sun, Mar 29, 2020 at 11:48:09AM +0100, Russell King wrote: > > > diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c > > > index fa5641615db6..ee13b11c5298 100644 > > > --- a/drivers/gpio/gpio-mvebu.c > > > +++ b/drivers/gpio/gpio-mvebu.c > > > @@ -1132,6 +1132,9 @@ static int mvebu_gpio_probe(struct platform_device *pdev) > > > } > > > > > > mvchip->clk = devm_clk_get(&pdev->dev, NULL); > > > + if (mvchip->clk == ERR_PTR(-EPROBE_DEFER)) > > > + return -EPROBE_DEFER; > > > + > > > /* Not all SoCs require a clock.*/ > > > if (!IS_ERR(mvchip->clk)) > > > clk_prepare_enable(mvchip->clk); > > > > I'd say the following is the right thing to do here: > > > > mvchip->clk = devm_clk_get_optional(...); > > if (IS_ERR(mvchip->clk)) > > return ... > > It's not that simple. The clock is required for Armada 370, and is > optional for Armada 8040. I'd say it is still the right approach here. On Armada 370 the dtb then has a clk and on Armada 8040 it doesn't. So if with devm_clk_get_optional() something goes wrong that's because the dtb is wrong. And in fact the handling is even better than with your suggested patch as every error (but EPROBE_DEFER) is ignored instead of passed to the caller with your (and the existing) approach. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ |
