+ linux-arm-kernel, maintainers, devicetree Shawn, Sascha: should this driver be listed under the Freescale IMX MAINTAINERS entry?
On Wed, Jan 14, 2015 at 03:36:49PM -0800, [email protected] wrote: > From: Alison Chaiken <[email protected]> > > PAD_EIM_D18 must be pulled low at boot in order for the parallel NOR > connected to the EIM switch to probe properly. Otherwise > cfi_qry_present() may return "U-V-]" rather than "Q-R-Y" if the > PAD_EIM_D18 is high. Add a nor-gpios property to the nor node in the > SabreAuto device-tree and add a function to the imx-weim probe to set > GPIO5 to drive the pad. > > Signed-off-by: Alison Chaiken <[email protected]> > --- > arch/arm/boot/dts/imx6qdl-sabreauto.dtsi | 1 + > drivers/bus/imx-weim.c | 43 > ++++++++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+) > > diff --git a/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi > b/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi > index 009abd6..dd5e3bc 100644 > --- a/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi > @@ -454,5 +454,6 @@ > bank-width = <2>; > fsl,weim-cs-timing = <0x00620081 0x00000001 0x1c022000 > 0x0000c000 0x1404a38e 0x00000000>; > + nor-gpios = <&gpio5 4 GPIO_ACTIVE_LOW>; Such a binding needs to be documented. Also, if it's going to be named generically like that, it needs to be generically useful and supported under MTD code, not platform-specific bus code. So what pin is this, exactly? A write-protect pin? An address pin? A toaster control, where the toaster is keeping the flash too hot? > }; > }; > diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c > index 0958b69..b3c2ca6 100644 > --- a/drivers/bus/imx-weim.c > +++ b/drivers/bus/imx-weim.c > @@ -14,6 +14,8 @@ > #include <linux/mfd/syscon.h> > #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h> > #include <linux/regmap.h> > +#include <linux/of_gpio.h> > +#include <linux/gpio.h> > > struct imx_weim_devtype { > unsigned int cs_count; > @@ -108,6 +110,40 @@ err: > return -EINVAL; > } > > +/* set the GPIO to control PAD_EIM_D18 so cfi_qry_present() works properly */ > +static int __init nor_gpio_setup(struct device_node *np, struct device > *parent) > +{ > + unsigned nor_gpio, level; > + enum of_gpio_flags of_flags; > + int ret; > + > + nor_gpio = of_get_named_gpio_flags(np, "nor-gpios", 0, &of_flags); > + > + /* this child is not a NOR chip */ > + if (!nor_gpio) > + return 0; > + > + if (gpio_is_valid(nor_gpio)) { > + ret = devm_gpio_request_one(parent, nor_gpio, > + GPIOF_DIR_OUT, "nor-gpio"); > + } else { > + ret = -ENODEV; > + goto out; > + } > + > + if (ret < 0) > + goto out; > + > + level = ((of_flags == OF_GPIO_ACTIVE_LOW) ? 0 : 1); > + > + gpio_set_value(nor_gpio, level); > + > + return 0; > +out: > + dev_err(parent, "Unable to request EIM_D18 GPIO for NOR.\n"); > + return ret; > +} > + > /* Parse and set the timing for this device. */ > static int __init weim_timing_setup(struct device_node *np, void __iomem > *base, > const struct imx_weim_devtype *devtype) > @@ -160,6 +196,13 @@ static int __init weim_parse_dt(struct platform_device > *pdev, > child->full_name); > return ret; > } > + > + ret = nor_gpio_setup(child, &pdev->dev); > + if (ret) { > + dev_err(&pdev->dev, "%s gpios setup failed.\n", > + child->full_name); > + return ret; > + } > } > > ret = of_platform_populate(pdev->dev.of_node, Brian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
