commit: de88747f514a4e0cca416a8871de2302f4f77790 From: Andrew Lunn <[email protected]> Date: Sun, 3 Feb 2013 11:34:26 +0100 Subject: gpio: mvebu: Add clk support to prevent lockup
The kirkwood SoC GPIO cores use the runit clock. Add code to clk_prepare_enable() runit, otherwise there is a danger of locking up the SoC by accessing the GPIO registers when runit clock is not ticking. Reported-by: Simon Baatz <[email protected]> Signed-off-by: Andrew Lunn <[email protected]> Tested-by: Simon Baatz <[email protected]> Acked-by: Linus Walleij <[email protected]> Cc: <[email protected]> Signed-off-by: Jason Cooper <[email protected]> --- arch/arm/boot/dts/kirkwood.dtsi | 2 ++ drivers/gpio/gpio-mvebu.c | 7 +++++++ 2 files changed, 9 insertions(+) diff --git a/arch/arm/boot/dts/kirkwood.dtsi b/arch/arm/boot/dts/kirkwood.dtsi index 19709fb..cf8e892 100644 --- a/arch/arm/boot/dts/kirkwood.dtsi +++ b/arch/arm/boot/dts/kirkwood.dtsi @@ -38,6 +38,7 @@ interrupt-controller; #interrupt-cells = <2>; interrupts = <35>, <36>, <37>, <38>; + clocks = <&gate_clk 7>; }; gpio1: gpio@10140 { @@ -49,6 +50,7 @@ interrupt-controller; #interrupt-cells = <2>; interrupts = <39>, <40>, <41>; + clocks = <&gate_clk 7>; }; serial@12000 { diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index 7472182..61a6fde 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -42,6 +42,7 @@ #include <linux/io.h> #include <linux/of_irq.h> #include <linux/of_device.h> +#include <linux/clk.h> #include <linux/pinctrl/consumer.h> /* @@ -496,6 +497,7 @@ static int mvebu_gpio_probe(struct platform_device *pdev) struct resource *res; struct irq_chip_generic *gc; struct irq_chip_type *ct; + struct clk *clk; unsigned int ngpios; int soc_variant; int i, cpu, id; @@ -529,6 +531,11 @@ static int mvebu_gpio_probe(struct platform_device *pdev) return id; } + clk = devm_clk_get(&pdev->dev, NULL); + /* Not all SoCs require a clock.*/ + if (!IS_ERR(clk)) + clk_prepare_enable(clk); + mvchip->soc_variant = soc_variant; mvchip->chip.label = dev_name(&pdev->dev); mvchip->chip.dev = &pdev->dev; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
