ARM: ux500: implement pin API

Implement an API to allow a list of pincfgs to be remuxed to active
and sleep modes, for power saving. This is not exported on purpose,
because it is not to be called by drivers directly.
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/mach-ux500/Makefile

@@ -3,7 +3,7 @@
 #
 
 obj-y				:= clock.o cpu.o devices.o devices-common.o \
-				   id.o usb.o timer.o
+				   id.o pins.o usb.o timer.o
 obj-$(CONFIG_CACHE_L2X0)	+= cache-l2x0.o
 obj-$(CONFIG_UX500_SOC_DB5500)	+= cpu-db5500.o dma-db5500.o
 obj-$(CONFIG_UX500_SOC_DB8500)	+= cpu-db8500.o devices-db8500.o

arch/arm/mach-ux500/board-mop500-pins.c

@@ -14,6 +14,7 @@
 #include <mach/hardware.h>
 
 #include "pins-db8500.h"
+#include "pins.h"
 
 static pin_cfg_t mop500_pins_common[] = {
 	/* I2C */

arch/arm/mach-ux500/pins.c

+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/err.h>
+#include <plat/pincfg.h>
+
+#include "pins.h"
+
+static LIST_HEAD(pin_lookups);
+static DEFINE_MUTEX(pin_lookups_mutex);
+static DEFINE_SPINLOCK(pins_lock);
+
+void __init ux500_pins_add(struct ux500_pin_lookup *pl, size_t num)
+{
+	mutex_lock(&pin_lookups_mutex);
+
+	while (num--) {
+		list_add_tail(&pl->node, &pin_lookups);
+		pl++;
+	}
+
+	mutex_unlock(&pin_lookups_mutex);
+}
+
+struct ux500_pins *ux500_pins_get(const char *name)
+{
+	struct ux500_pins *pins = NULL;
+	struct ux500_pin_lookup *pl;
+
+	mutex_lock(&pin_lookups_mutex);
+
+	list_for_each_entry(pl, &pin_lookups, node) {
+		if (!strcmp(pl->name, name)) {
+			pins = pl->pins;
+			goto out;
+		}
+	}
+
+out:
+	mutex_unlock(&pin_lookups_mutex);
+	return pins;
+}
+
+int ux500_pins_enable(struct ux500_pins *pins)
+{
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&pins_lock, flags);
+
+	if (pins->usage++ == 0)
+		ret = nmk_config_pins(pins->cfg, pins->num);
+
+	spin_unlock_irqrestore(&pins_lock, flags);
+	return ret;
+}
+
+int ux500_pins_disable(struct ux500_pins *pins)
+{
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&pins_lock, flags);
+
+	if (WARN_ON(pins->usage == 0))
+		goto out;
+
+	if (--pins->usage == 0)
+		ret = nmk_config_pins_sleep(pins->cfg, pins->num);
+
+out:
+	spin_unlock_irqrestore(&pins_lock, flags);
+	return ret;
+}
+
+void ux500_pins_put(struct ux500_pins *pins)
+{
+	WARN_ON(!pins);
+}

arch/arm/mach-ux500/pins.h

+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#ifndef __MACH_UX500_PINS_H
+#define __MACH_UX500_PINS_H
+
+#include <linux/list.h>
+#include <plat/pincfg.h>
+
+#define PIN_LOOKUP(_name, _pins)	\
+{					\
+	.name	= _name,		\
+	.pins	= _pins,		\
+}
+
+#define UX500_PINS(name, pins...)			\
+struct ux500_pins name = {				\
+	.cfg = (pin_cfg_t[]) {pins},			\
+	.num = ARRAY_SIZE(((pin_cfg_t[]) {pins})),	\
+}
+
+struct ux500_pins {
+	int usage;
+	int num;
+	pin_cfg_t *cfg;
+};
+
+struct ux500_pin_lookup {
+	struct list_head	node;
+	const char		*name;
+	struct ux500_pins	*pins;
+};
+
+void __init ux500_pins_add(struct ux500_pin_lookup *pl, size_t num);
+void __init ux500_offchip_gpio_init(struct ux500_pins *pins);
+struct ux500_pins *ux500_pins_get(const char *name);
+int ux500_pins_enable(struct ux500_pins *pins);
+int ux500_pins_disable(struct ux500_pins *pins);
+void ux500_pins_put(struct ux500_pins *pins);
+int pins_for_u9500(void);
+
+#endif