powerpc/mpc512x: Add gpio driver

Signed-off-by Matthias Fuchs <[email protected]>

---
=A0arch/powerpc/include/asm/mpc512x_gpio.h | =A0 30 +++++ =A0arch/powerpc/platforms/Kconfig =A0 =A0 =A0 =A0 =A0| =A0 =A09 ++ =A0arch/powerpc/sysdev/Makefile =A0 =A0 =A0 =A0 =A0 =A0| =A0 =A01 + =A0arch/powerpc/sysdev/mpc512x_gpio.c =A0 =A0 =A0| =A0179 +++++++++++++++=

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arch/powerpc/include/asm/mpc512x_gpio.h new file +5 -0

@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2010 Matthias Fuchs <[email protected]>, esd gmbh
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2

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arch/powerpc/sysdev/mpc512x_gpio.c new file +15 -0

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+/*
+ * MPC512x gpio driver
+ *
+ * Copyright (c) 2010 Matthias Fuchs <[email protected]>, esd gmbh
+ *
+ * derived from ppc4xx gpio driver
+ *
+ * Copyright (c) 2008 Harris Corporation
+ * Copyright (c) 2008 Sascha Hauer <[email protected]>, Pengutronix
+ * Copyright (c) MontaVista Software, Inc. 2008.
+ *
+ * Author: Steve Falco <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2

arch/powerpc/sysdev/mpc512x_gpio.c new file +25 -0

+
+struct mpc512x_chip {
+ =A0 =A0 =A0 struct of_mm_gpio_chip mm_gc;
+ =A0 =A0 =A0 spinlock_t lock;
+};
+
+/*
+ * GPIO LIB API implementation for GPIOs
+ *
+ * There are a maximum of 32 gpios in each gpio controller.
+ */
+static inline struct mpc512x_chip *
+to_mpc512x_gpiochip(struct of_mm_gpio_chip *mm_gc)
+{
+ =A0 =A0 =A0 return container_of(mm_gc, struct mpc512x_chip, mm_gc);
+}
+
+static int mpc512x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
+{
+ =A0 =A0 =A0 struct of_mm_gpio_chip *mm_gc =3D to_of_mm_gpio_chip(gc);
+ =A0 =A0 =A0 struct mpc512x_gpio_regs __iomem *regs =3D mm_gc->regs;
+
+ =A0 =A0 =A0 return in_be32(&regs->gpdat) & GPIO_MASK(gpio);
+}
+

arch/powerpc/sysdev/mpc512x_gpio.c new file +66 -0

+}
+
+static void
+mpc512x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ =A0 =A0 =A0 struct of_mm_gpio_chip *mm_gc =3D to_of_mm_gpio_chip(gc);
+ =A0 =A0 =A0 struct mpc512x_chip *chip =3D to_mpc512x_gpiochip(mm_gc);
+ =A0 =A0 =A0 unsigned long flags;
+
+ =A0 =A0 =A0 spin_lock_irqsave(&chip->lock, flags);
+
+ =A0 =A0 =A0 __mpc512x_gpio_set(gc, gpio, val);
+
+ =A0 =A0 =A0 spin_unlock_irqrestore(&chip->lock, flags);
+
+ =A0 =A0 =A0 pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
+}
+
+static int mpc512x_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+ =A0 =A0 =A0 struct of_mm_gpio_chip *mm_gc =3D to_of_mm_gpio_chip(gc);
+ =A0 =A0 =A0 struct mpc512x_chip *chip =3D to_mpc512x_gpiochip(mm_gc);
+ =A0 =A0 =A0 struct mpc512x_gpio_regs __iomem *regs =3D mm_gc->regs;
+ =A0 =A0 =A0 unsigned long flags;
+
+ =A0 =A0 =A0 spin_lock_irqsave(&chip->lock, flags);
+
+ =A0 =A0 =A0 /* Disable open-drain function */
+ =A0 =A0 =A0 clrbits32(&regs->gpodr, GPIO_MASK(gpio));
+
+ =A0 =A0 =A0 /* Float the pin */
+ =A0 =A0 =A0 clrbits32(&regs->gpdir, GPIO_MASK(gpio));
+
+ =A0 =A0 =A0 spin_unlock_irqrestore(&chip->lock, flags);
+
+ =A0 =A0 =A0 return 0;
+}
+
+static int
+mpc512x_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ =A0 =A0 =A0 struct of_mm_gpio_chip *mm_gc =3D to_of_mm_gpio_chip(gc);
+ =A0 =A0 =A0 struct mpc512x_chip *chip =3D to_mpc512x_gpiochip(mm_gc);
+ =A0 =A0 =A0 struct mpc512x_gpio_regs __iomem *regs =3D mm_gc->regs;
+ =A0 =A0 =A0 unsigned long flags;
+
+ =A0 =A0 =A0 spin_lock_irqsave(&chip->lock, flags);
+
+ =A0 =A0 =A0 /* First set initial value */
+ =A0 =A0 =A0 __mpc512x_gpio_set(gc, gpio, val);
+
+ =A0 =A0 =A0 /* Disable open-drain function */
+ =A0 =A0 =A0 clrbits32(&regs->gpodr, GPIO_MASK(gpio));
+
+ =A0 =A0 =A0 /* Drive the pin */
+ =A0 =A0 =A0 setbits32(&regs->gpdir, GPIO_MASK(gpio));
+
+ =A0 =A0 =A0 spin_unlock_irqrestore(&chip->lock, flags);
+
+ =A0 =A0 =A0 pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
+
+ =A0 =A0 =A0 return 0;
+}
+
+static int __init mpc512x_add_gpiochips(void)
+{

Review

Quoted 3 lines

+ =A0 =A0 =A0 return 0;

(quoted diff) +2 -0

+}
+arch_initcall(mpc512x_add_gpiochips);

=20
Don't do this. Either make this a proper of_platform device driver, or call mpc512x_add_gpiochips() explicitly from the arch platform setup code. Otherwise, if the kernel is built for multiplatform, this function will get executed regardless of the platform.

Hi Grant,

thanks for comments. I will post an updated version soon.

Quoted 8 lines · Grant Likely

Review

Quoted 3 lines

+ =A0 =A0 =A0 return 0;

(quoted diff) +2 -0

+}
+arch_initcall(mpc512x_add_gpiochips);

Don't do this. =A0Either make this a proper of_platform device driver, or call mpc512x_add_gpiochips() explicitly from the arch platform setup code. =A0Otherwise, if the kernel is built for multiplatform, this function will get executed regardless of the platform.

In this case I prefer moving the call to the platform code. I tested the driver on one of our 5123 boards. Shall I add it to mpc5121_ads.c:mpc5121_ads_setup_arch() also? So it's at least called on the reference board? I not sure if there are some LEDs or buttons that could use it.