path: root/arch/arm/plat-nomadik/gpio.c

/*
 * Generic GPIO driver for logic cells found in the Nomadik SoC
 *
 * Copyright (C) 2008,2009 STMicroelectronics
 * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
 *   Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>

#include <plat/pincfg.h>
#include <mach/hardware.h>
#include <mach/gpio.h>

/*
 * The GPIO module in the Nomadik family of Systems-on-Chip is an
 * AMBA device, managing 32 pins and alternate functions.  The logic block
 * is currently used in the Nomadik and ux500.
 *
 * Symbols in this file are called "nmk_gpio" for "nomadik gpio"
 */

static const u32 backup_regs[] = {
	NMK_GPIO_PDIS,
	NMK_GPIO_DIR,
	NMK_GPIO_AFSLA,
	NMK_GPIO_AFSLB,
	NMK_GPIO_SLPC,
	NMK_GPIO_RIMSC,
	NMK_GPIO_FIMSC,
	NMK_GPIO_RWIMSC,
	NMK_GPIO_FWIMSC,
};

struct nmk_gpio_chip {
	struct gpio_chip chip;
	void __iomem *addr;
	struct clk *clk;
	unsigned int bank;
	unsigned int parent_irq;
	unsigned int secondary_parent_irq;
	u32 (*get_secondary_status)(unsigned int bank);
	spinlock_t lock;
	/* Keep track of configured edges */
	u32 edge_rising;
	u32 edge_falling;
	u32 backup[ARRAY_SIZE(backup_regs)];
	/* Bitmap, 1 = pull up, 0 = pull down */
	u32 pull;
};

static void __nmk_gpio_set_mode(struct nmk_gpio_chip *nmk_chip,
				unsigned offset, int gpio_mode)
{
	u32 bit = 1 << offset;
	u32 afunc, bfunc;

	afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & ~bit;
	bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & ~bit;
	if (gpio_mode & NMK_GPIO_ALT_A)
		afunc |= bit;
	if (gpio_mode & NMK_GPIO_ALT_B)
		bfunc |= bit;
	writel(afunc, nmk_chip->addr + NMK_GPIO_AFSLA);
	writel(bfunc, nmk_chip->addr + NMK_GPIO_AFSLB);
}

static void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip,
				unsigned offset, enum nmk_gpio_slpm mode)
{
	u32 bit = 1 << offset;
	u32 slpm;

	slpm = readl(nmk_chip->addr + NMK_GPIO_SLPC);
	if (mode == NMK_GPIO_SLPM_NOCHANGE)
		slpm |= bit;
	else
		slpm &= ~bit;
	writel(slpm, nmk_chip->addr + NMK_GPIO_SLPC);
}

static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
				unsigned offset, enum nmk_gpio_pull pull)
{
	u32 bit = 1 << offset;
	u32 pdis;

	pdis = readl(nmk_chip->addr + NMK_GPIO_PDIS);
	if (pull == NMK_GPIO_PULL_NONE)
		pdis |= bit;
	else
		pdis &= ~bit;
	writel(pdis, nmk_chip->addr + NMK_GPIO_PDIS);

	if (pull == NMK_GPIO_PULL_UP) {
		nmk_chip->pull |= bit;
		writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
	} else if (pull == NMK_GPIO_PULL_DOWN) {
		nmk_chip->pull &= ~bit;
		writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
	}
}

static void __nmk_gpio_make_input(struct nmk_gpio_chip *nmk_chip,
				  unsigned offset)
{
	writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
}

static void __nmk_gpio_set_output(struct nmk_gpio_chip *nmk_chip,
				  unsigned offset, int val)
{
	if (val)
		writel(1 << offset, nmk_chip->addr + NMK_GPIO_DATS);
	else
		writel(1 << offset, nmk_chip->addr + NMK_GPIO_DATC);
}

static void __nmk_gpio_make_output(struct nmk_gpio_chip *nmk_chip,
				  unsigned offset, int val)
{
	writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS);
	__nmk_gpio_set_output(nmk_chip, offset, val);
}

static void __nmk_config_pin(struct nmk_gpio_chip *nmk_chip, unsigned offset,
			     pin_cfg_t cfg, bool sleep)
{
	static const char *afnames[] = {
		[NMK_GPIO_ALT_GPIO]	= "GPIO",
		[NMK_GPIO_ALT_A]	= "A",
		[NMK_GPIO_ALT_B]	= "B",
		[NMK_GPIO_ALT_C]	= "C"
	};
	static const char *pullnames[] = {
		[NMK_GPIO_PULL_NONE]	= "none",
		[NMK_GPIO_PULL_UP]	= "up",
		[NMK_GPIO_PULL_DOWN]	=