Staging: dream: add gpio and pmem support

This adds generic_gpio and pmem support, both are needed for other
dream drivers.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/dream/generic_gpio.c

+/* arch/arm/mach-msm/generic_gpio.c
+ *
+ * Copyright (C) 2007 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <asm/gpio.h>
+#include "gpio_chip.h"
+
+#define GPIO_NUM_TO_CHIP_INDEX(gpio) ((gpio)>>5)
+
+struct gpio_state {
+	unsigned long flags;
+	int refcount;
+};
+
+static DEFINE_SPINLOCK(gpio_chips_lock);
+static LIST_HEAD(gpio_chip_list);
+static struct gpio_chip **gpio_chip_array;
+static unsigned long gpio_chip_array_size;
+
+int register_gpio_chip(struct gpio_chip *new_gpio_chip)
+{
+	int err = 0;
+	struct gpio_chip *gpio_chip;
+	int i;
+	unsigned long irq_flags;
+	unsigned int chip_array_start_index, chip_array_end_index;
+
+	new_gpio_chip->state = kzalloc((new_gpio_chip->end + 1 - new_gpio_chip->start) * sizeof(new_gpio_chip->state[0]), GFP_KERNEL);
+	if (new_gpio_chip->state == NULL) {
+		printk(KERN_ERR "register_gpio_chip: failed to allocate state\n");
+		return -ENOMEM;
+	}
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip_array_start_index = GPIO_NUM_TO_CHIP_INDEX(new_gpio_chip->start);
+	chip_array_end_index = GPIO_NUM_TO_CHIP_INDEX(new_gpio_chip->end);
+	if (chip_array_end_index >= gpio_chip_array_size) {
+		struct gpio_chip **new_gpio_chip_array;
+		unsigned long new_gpio_chip_array_size = chip_array_end_index + 1;
+
+		new_gpio_chip_array = kmalloc(new_gpio_chip_array_size * sizeof(new_gpio_chip_array[0]), GFP_ATOMIC);
+		if (new_gpio_chip_array == NULL) {
+			printk(KERN_ERR "register_gpio_chip: failed to allocate array\n");
+			err = -ENOMEM;
+			goto failed;
+		}
+		for (i = 0; i < gpio_chip_array_size; i++)
+			new_gpio_chip_array[i] = gpio_chip_array[i];
+		for (i = gpio_chip_array_size; i < new_gpio_chip_array_size; i++)
+			new_gpio_chip_array[i] = NULL;
+		gpio_chip_array = new_gpio_chip_array;
+		gpio_chip_array_size = new_gpio_chip_array_size;
+	}
+	list_for_each_entry(gpio_chip, &gpio_chip_list, list) {
+		if (gpio_chip->start > new_gpio_chip->end) {
+			list_add_tail(&new_gpio_chip->list, &gpio_chip->list);
+			goto added;
+		}
+		if (gpio_chip->end >= new_gpio_chip->start) {
+			printk(KERN_ERR "register_gpio_source %u-%u overlaps with %u-%u\n",
+			       new_gpio_chip->start, new_gpio_chip->end,
+			       gpio_chip->start, gpio_chip->end);
+			err = -EBUSY;
+			goto failed;
+		}
+	}
+	list_add_tail(&new_gpio_chip->list, &gpio_chip_list);
+added:
+	for (i = chip_array_start_index; i <= chip_array_end_index; i++) {
+		if (gpio_chip_array[i] == NULL || gpio_chip_array[i]->start > new_gpio_chip->start)
+			gpio_chip_array[i] = new_gpio_chip;
+	}
+failed:
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+	if (err)
+		kfree(new_gpio_chip->state);
+	return err;
+}
+
+static struct gpio_chip *get_gpio_chip_locked(unsigned int gpio)
+{
+	unsigned long i;
+	struct gpio_chip *chip;
+
+	i = GPIO_NUM_TO_CHIP_INDEX(gpio);
+	if (i >= gpio_chip_array_size)
+		return NULL;
+	chip = gpio_chip_array[i];
+	if (chip == NULL)
+		return NULL;
+	list_for_each_entry_from(chip, &gpio_chip_list, list) {
+		if (gpio < chip->start)
+			return NULL;
+		if (gpio <= chip->end)
+			return chip;
+	}
+	return NULL;
+}
+
+static int request_gpio(unsigned int gpio, unsigned long flags)
+{
+	int err = 0;
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+	unsigned long chip_index;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip == NULL) {
+		err = -EINVAL;
+		goto err;
+	}
+	chip_index = gpio - chip->start;
+	if (chip->state[chip_index].refcount == 0) {
+		chip->configure(chip, gpio, flags);
+		chip->state[chip_index].flags = flags;
+		chip->state[chip_index].refcount++;
+	} else if ((flags & IRQF_SHARED) && (chip->state[chip_index].flags & IRQF_SHARED))
+		chip->state[chip_index].refcount++;
+	else
+		err = -EBUSY;
+err:
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+	return err;
+}
+
+int gpio_request(unsigned gpio, const char *label)
+{
+	return request_gpio(gpio, 0);
+}
+EXPORT_SYMBOL(gpio_request);
+
+void gpio_free(unsigned gpio)
+{
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+	unsigned long chip_index;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip) {
+		chip_index = gpio - chip->start;
+		chip->state[chip_index].refcount--;
+	}
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+}
+EXPORT_SYMBOL(gpio_free);
+
+static int gpio_get_irq_num(unsigned int gpio, unsigned int *irqp, unsigned long *irqnumflagsp)
+{
+	int ret = -ENOTSUPP;
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip && chip->get_irq_num)
+		ret = chip->get_irq_num(chip, gpio, irqp, irqnumflagsp);
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+	return ret;
+}
+
+int gpio_to_irq(unsigned gpio)
+{
+	int ret, irq;
+	ret = gpio_get_irq_num(gpio, &irq, NULL);
+	if (ret)
+		return ret;
+	return irq;
+}
+EXPORT_SYMBOL(gpio_to_irq);
+
+int gpio_configure(unsigned int gpio, unsigned long flags)
+{
+	int ret = -ENOTSUPP;
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip)
+		ret = chip->configure(chip, gpio, flags);
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+	return ret;
+}
+EXPORT_SYMBOL(gpio_configure);
+
+int gpio_direction_input(unsigned gpio)
+{
+	return gpio_configure(gpio, GPIOF_INPUT);
+}
+EXPORT_SYMBOL(gpio_direction_input);
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+	gpio_set_value(gpio, value);
+	return gpio_configure(gpio, GPIOF_DRIVE_OUTPUT);
+}
+EXPORT_SYMBOL(gpio_direction_output);
+
+int gpio_get_value(unsigned gpio)
+{
+	int ret = -ENOTSUPP;
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip && chip->read)
+		ret = chip->read(chip, gpio);
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+	return ret;
+}
+EXPORT_SYMBOL(gpio_get_value);
+
+void gpio_set_value(unsigned gpio, int on)
+{
+	int ret = -ENOTSUPP;
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip && chip->write)
+		ret = chip->write(chip, gpio, on);
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+}
+EXPORT_SYMBOL(gpio_set_value);
+
+int gpio_read_detect_status(unsigned int gpio)
+{
+	int ret = -ENOTSUPP;
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip && chip->read_detect_status)
+		ret = chip->read_detect_status(chip, gpio);
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+	return ret;
+}
+EXPORT_SYMBOL(gpio_read_detect_status);
+
+int gpio_clear_detect_status(unsigned int gpio)
+{
+	int ret = -ENOTSUPP;
+	struct gpio_chip *chip;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&gpio_chips_lock, irq_flags);
+	chip = get_gpio_chip_locked(gpio);
+	if (chip && chip->clear_detect_status)
+		ret = chip->clear_detect_status(chip, gpio);
+	spin_unlock_irqrestore(&gpio_chips_lock, irq_flags);
+	return ret;
+}
+EXPORT_SYMBOL(gpio_clear_detect_status);