diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/powerpc/sysdev/simple_gpio.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/powerpc/sysdev/simple_gpio.c')
-rw-r--r-- | kernel/arch/powerpc/sysdev/simple_gpio.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/sysdev/simple_gpio.c b/kernel/arch/powerpc/sysdev/simple_gpio.c new file mode 100644 index 000000000..ff5e73230 --- /dev/null +++ b/kernel/arch/powerpc/sysdev/simple_gpio.c @@ -0,0 +1,152 @@ +/* + * Simple Memory-Mapped GPIOs + * + * Copyright (c) MontaVista Software, Inc. 2008. + * + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/types.h> +#include <linux/ioport.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/gpio.h> +#include <linux/slab.h> +#include <asm/prom.h> +#include "simple_gpio.h" + +struct u8_gpio_chip { + struct of_mm_gpio_chip mm_gc; + spinlock_t lock; + + /* shadowed data register to clear/set bits safely */ + u8 data; +}; + +static struct u8_gpio_chip *to_u8_gpio_chip(struct of_mm_gpio_chip *mm_gc) +{ + return container_of(mm_gc, struct u8_gpio_chip, mm_gc); +} + +static u8 u8_pin2mask(unsigned int pin) +{ + return 1 << (8 - 1 - pin); +} + +static int u8_gpio_get(struct gpio_chip *gc, unsigned int gpio) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + + return in_8(mm_gc->regs) & u8_pin2mask(gpio); +} + +static void u8_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct u8_gpio_chip *u8_gc = to_u8_gpio_chip(mm_gc); + unsigned long flags; + + spin_lock_irqsave(&u8_gc->lock, flags); + + if (val) + u8_gc->data |= u8_pin2mask(gpio); + else + u8_gc->data &= ~u8_pin2mask(gpio); + + out_8(mm_gc->regs, u8_gc->data); + + spin_unlock_irqrestore(&u8_gc->lock, flags); +} + +static int u8_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio) +{ + return 0; +} + +static int u8_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) +{ + u8_gpio_set(gc, gpio, val); + return 0; +} + +static void u8_gpio_save_regs(struct of_mm_gpio_chip *mm_gc) +{ + struct u8_gpio_chip *u8_gc = to_u8_gpio_chip(mm_gc); + + u8_gc->data = in_8(mm_gc->regs); +} + +static int __init u8_simple_gpiochip_add(struct device_node *np) +{ + int ret; + struct u8_gpio_chip *u8_gc; + struct of_mm_gpio_chip *mm_gc; + struct gpio_chip *gc; + + u8_gc = kzalloc(sizeof(*u8_gc), GFP_KERNEL); + if (!u8_gc) + return -ENOMEM; + + spin_lock_init(&u8_gc->lock); + + mm_gc = &u8_gc->mm_gc; + gc = &mm_gc->gc; + + mm_gc->save_regs = u8_gpio_save_regs; + gc->ngpio = 8; + gc->direction_input = u8_gpio_dir_in; + gc->direction_output = u8_gpio_dir_out; + gc->get = u8_gpio_get; + gc->set = u8_gpio_set; + + ret = of_mm_gpiochip_add(np, mm_gc); + if (ret) + goto err; + return 0; +err: + kfree(u8_gc); + return ret; +} + +void __init simple_gpiochip_init(const char *compatible) +{ + struct device_node *np; + + for_each_compatible_node(np, NULL, compatible) { + int ret; + struct resource r; + + ret = of_address_to_resource(np, 0, &r); + if (ret) + goto err; + + switch (resource_size(&r)) { + case 1: + ret = u8_simple_gpiochip_add(np); + if (ret) + goto err; + break; + default: + /* + * Whenever you need support for GPIO bank width > 1, + * please just turn u8_ code into huge macros, and + * construct needed uX_ code with it. + */ + ret = -ENOSYS; + goto err; + } + continue; +err: + pr_err("%s: registration failed, status %d\n", + np->full_name, ret); + } +} |