[v3,1/5] gpio: gpio-mxc: copy plat-mxc/gpio.c into drivers/gpio

As the first patch of the series that moves plat-mxc gpio driver into
drivers/gpio, it copies arch/arm/plat-mxc/gpio.c into
drivers/gpio/gpio-mxc.c.  The later patches will make necessary
changes to the driver, migrate the existing users to it, and lastly
deletes plat-mxc gpio driver.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/gpio/gpio-mxc.c |  361 +++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 361 insertions(+), 0 deletions(-)
 create mode 100644 drivers/gpio/gpio-mxc.c

On Sat, Jun 04, 2011 at 07:47:14PM +0800, Shawn Guo wrote:
> As the first patch of the series that moves plat-mxc gpio driver into
> drivers/gpio, it copies arch/arm/plat-mxc/gpio.c into
> drivers/gpio/gpio-mxc.c.  The later patches will make necessary
> changes to the driver, migrate the existing users to it, and lastly
> deletes plat-mxc gpio driver.
> 
> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> ---
>  drivers/gpio/gpio-mxc.c |  361 +++++++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 361 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/gpio/gpio-mxc.c

Ditto to my comments on the gpio-mxs driver, I'd like you to rework
how the driver file is moved before it is modified.

g.

> 
> diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
> new file mode 100644
> index 0000000..6cd6d7f
> --- /dev/null
> +++ b/drivers/gpio/gpio-mxc.c
> @@ -0,0 +1,361 @@
> +/*
> + * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
> + * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
> + *
> + * Based on code from Freescale,
> + * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
> + *
> + * 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.
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/gpio.h>
> +#include <mach/hardware.h>
> +#include <asm-generic/bug.h>
> +
> +static struct mxc_gpio_port *mxc_gpio_ports;
> +static int gpio_table_size;
> +
> +#define cpu_is_mx1_mx2()	(cpu_is_mx1() || cpu_is_mx2())
> +
> +#define GPIO_DR		(cpu_is_mx1_mx2() ? 0x1c : 0x00)
> +#define GPIO_GDIR	(cpu_is_mx1_mx2() ? 0x00 : 0x04)
> +#define GPIO_PSR	(cpu_is_mx1_mx2() ? 0x24 : 0x08)
> +#define GPIO_ICR1	(cpu_is_mx1_mx2() ? 0x28 : 0x0C)
> +#define GPIO_ICR2	(cpu_is_mx1_mx2() ? 0x2C : 0x10)
> +#define GPIO_IMR	(cpu_is_mx1_mx2() ? 0x30 : 0x14)
> +#define GPIO_ISR	(cpu_is_mx1_mx2() ? 0x34 : 0x18)
> +
> +#define GPIO_INT_LOW_LEV	(cpu_is_mx1_mx2() ? 0x3 : 0x0)
> +#define GPIO_INT_HIGH_LEV	(cpu_is_mx1_mx2() ? 0x2 : 0x1)
> +#define GPIO_INT_RISE_EDGE	(cpu_is_mx1_mx2() ? 0x0 : 0x2)
> +#define GPIO_INT_FALL_EDGE	(cpu_is_mx1_mx2() ? 0x1 : 0x3)
> +#define GPIO_INT_NONE		0x4
> +
> +/* Note: This driver assumes 32 GPIOs are handled in one register */
> +
> +static void _clear_gpio_irqstatus(struct mxc_gpio_port *port, u32 index)
> +{
> +	__raw_writel(1 << index, port->base + GPIO_ISR);
> +}
> +
> +static void _set_gpio_irqenable(struct mxc_gpio_port *port, u32 index,
> +				int enable)
> +{
> +	u32 l;
> +
> +	l = __raw_readl(port->base + GPIO_IMR);
> +	l = (l & (~(1 << index))) | (!!enable << index);
> +	__raw_writel(l, port->base + GPIO_IMR);
> +}
> +
> +static void gpio_ack_irq(struct irq_data *d)
> +{
> +	u32 gpio = irq_to_gpio(d->irq);
> +	_clear_gpio_irqstatus(&mxc_gpio_ports[gpio / 32], gpio & 0x1f);
> +}
> +
> +static void gpio_mask_irq(struct irq_data *d)
> +{
> +	u32 gpio = irq_to_gpio(d->irq);
> +	_set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 0);
> +}
> +
> +static void gpio_unmask_irq(struct irq_data *d)
> +{
> +	u32 gpio = irq_to_gpio(d->irq);
> +	_set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 1);
> +}
> +
> +static int mxc_gpio_get(struct gpio_chip *chip, unsigned offset);
> +
> +static int gpio_set_irq_type(struct irq_data *d, u32 type)
> +{
> +	u32 gpio = irq_to_gpio(d->irq);
> +	struct mxc_gpio_port *port = &mxc_gpio_ports[gpio / 32];
> +	u32 bit, val;
> +	int edge;
> +	void __iomem *reg = port->base;
> +
> +	port->both_edges &= ~(1 << (gpio & 31));
> +	switch (type) {
> +	case IRQ_TYPE_EDGE_RISING:
> +		edge = GPIO_INT_RISE_EDGE;
> +		break;
> +	case IRQ_TYPE_EDGE_FALLING:
> +		edge = GPIO_INT_FALL_EDGE;
> +		break;
> +	case IRQ_TYPE_EDGE_BOTH:
> +		val = mxc_gpio_get(&port->chip, gpio & 31);
> +		if (val) {
> +			edge = GPIO_INT_LOW_LEV;
> +			pr_debug("mxc: set GPIO %d to low trigger\n", gpio);
> +		} else {
> +			edge = GPIO_INT_HIGH_LEV;
> +			pr_debug("mxc: set GPIO %d to high trigger\n", gpio);
> +		}
> +		port->both_edges |= 1 << (gpio & 31);
> +		break;
> +	case IRQ_TYPE_LEVEL_LOW:
> +		edge = GPIO_INT_LOW_LEV;
> +		break;
> +	case IRQ_TYPE_LEVEL_HIGH:
> +		edge = GPIO_INT_HIGH_LEV;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
> +	bit = gpio & 0xf;
> +	val = __raw_readl(reg) & ~(0x3 << (bit << 1));
> +	__raw_writel(val | (edge << (bit << 1)), reg);
> +	_clear_gpio_irqstatus(port, gpio & 0x1f);
> +
> +	return 0;
> +}
> +
> +static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
> +{
> +	void __iomem *reg = port->base;
> +	u32 bit, val;
> +	int edge;
> +
> +	reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
> +	bit = gpio & 0xf;
> +	val = __raw_readl(reg);
> +	edge = (val >> (bit << 1)) & 3;
> +	val &= ~(0x3 << (bit << 1));
> +	if (edge == GPIO_INT_HIGH_LEV) {
> +		edge = GPIO_INT_LOW_LEV;
> +		pr_debug("mxc: switch GPIO %d to low trigger\n", gpio);
> +	} else if (edge == GPIO_INT_LOW_LEV) {
> +		edge = GPIO_INT_HIGH_LEV;
> +		pr_debug("mxc: switch GPIO %d to high trigger\n", gpio);
> +	} else {
> +		pr_err("mxc: invalid configuration for GPIO %d: %x\n",
> +		       gpio, edge);
> +		return;
> +	}
> +	__raw_writel(val | (edge << (bit << 1)), reg);
> +}
> +
> +/* handle 32 interrupts in one status register */
> +static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
> +{
> +	u32 gpio_irq_no_base = port->virtual_irq_start;
> +
> +	while (irq_stat != 0) {
> +		int irqoffset = fls(irq_stat) - 1;
> +
> +		if (port->both_edges & (1 << irqoffset))
> +			mxc_flip_edge(port, irqoffset);
> +
> +		generic_handle_irq(gpio_irq_no_base + irqoffset);
> +
> +		irq_stat &= ~(1 << irqoffset);
> +	}
> +}
> +
> +/* MX1 and MX3 has one interrupt *per* gpio port */
> +static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc)
> +{
> +	u32 irq_stat;
> +	struct mxc_gpio_port *port = irq_get_handler_data(irq);
> +
> +	irq_stat = __raw_readl(port->base + GPIO_ISR) &
> +			__raw_readl(port->base + GPIO_IMR);
> +
> +	mxc_gpio_irq_handler(port, irq_stat);
> +}
> +
> +/* MX2 has one interrupt *for all* gpio ports */
> +static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc)
> +{
> +	int i;
> +	u32 irq_msk, irq_stat;
> +	struct mxc_gpio_port *port = irq_get_handler_data(irq);
> +
> +	/* walk through all interrupt status registers */
> +	for (i = 0; i < gpio_table_size; i++) {
> +		irq_msk = __raw_readl(port[i].base + GPIO_IMR);
> +		if (!irq_msk)
> +			continue;
> +
> +		irq_stat = __raw_readl(port[i].base + GPIO_ISR) & irq_msk;
> +		if (irq_stat)
> +			mxc_gpio_irq_handler(&port[i], irq_stat);
> +	}
> +}
> +
> +/*
> + * Set interrupt number "irq" in the GPIO as a wake-up source.
> + * While system is running, all registered GPIO interrupts need to have
> + * wake-up enabled. When system is suspended, only selected GPIO interrupts
> + * need to have wake-up enabled.
> + * @param  irq          interrupt source number
> + * @param  enable       enable as wake-up if equal to non-zero
> + * @return       This function returns 0 on success.
> + */
> +static int gpio_set_wake_irq(struct irq_data *d, u32 enable)
> +{
> +	u32 gpio = irq_to_gpio(d->irq);
> +	u32 gpio_idx = gpio & 0x1F;
> +	struct mxc_gpio_port *port = &mxc_gpio_ports[gpio / 32];
> +
> +	if (enable) {
> +		if (port->irq_high && (gpio_idx >= 16))
> +			enable_irq_wake(port->irq_high);
> +		else
> +			enable_irq_wake(port->irq);
> +	} else {
> +		if (port->irq_high && (gpio_idx >= 16))
> +			disable_irq_wake(port->irq_high);
> +		else
> +			disable_irq_wake(port->irq);
> +	}
> +
> +	return 0;
> +}
> +
> +static struct irq_chip gpio_irq_chip = {
> +	.name = "GPIO",
> +	.irq_ack = gpio_ack_irq,
> +	.irq_mask = gpio_mask_irq,
> +	.irq_unmask = gpio_unmask_irq,
> +	.irq_set_type = gpio_set_irq_type,
> +	.irq_set_wake = gpio_set_wake_irq,
> +};
> +
> +static void _set_gpio_direction(struct gpio_chip *chip, unsigned offset,
> +				int dir)
> +{
> +	struct mxc_gpio_port *port =
> +		container_of(chip, struct mxc_gpio_port, chip);
> +	u32 l;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&port->lock, flags);
> +	l = __raw_readl(port->base + GPIO_GDIR);
> +	if (dir)
> +		l |= 1 << offset;
> +	else
> +		l &= ~(1 << offset);
> +	__raw_writel(l, port->base + GPIO_GDIR);
> +	spin_unlock_irqrestore(&port->lock, flags);
> +}
> +
> +static void mxc_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
> +{
> +	struct mxc_gpio_port *port =
> +		container_of(chip, struct mxc_gpio_port, chip);
> +	void __iomem *reg = port->base + GPIO_DR;
> +	u32 l;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&port->lock, flags);
> +	l = (__raw_readl(reg) & (~(1 << offset))) | (!!value << offset);
> +	__raw_writel(l, reg);
> +	spin_unlock_irqrestore(&port->lock, flags);
> +}
> +
> +static int mxc_gpio_get(struct gpio_chip *chip, unsigned offset)
> +{
> +	struct mxc_gpio_port *port =
> +		container_of(chip, struct mxc_gpio_port, chip);
> +
> +	return (__raw_readl(port->base + GPIO_PSR) >> offset) & 1;
> +}
> +
> +static int mxc_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
> +{
> +	_set_gpio_direction(chip, offset, 0);
> +	return 0;
> +}
> +
> +static int mxc_gpio_direction_output(struct gpio_chip *chip,
> +				     unsigned offset, int value)
> +{
> +	mxc_gpio_set(chip, offset, value);
> +	_set_gpio_direction(chip, offset, 1);
> +	return 0;
> +}
> +
> +/*
> + * This lock class tells lockdep that GPIO irqs are in a different
> + * category than their parents, so it won't report false recursion.
> + */
> +static struct lock_class_key gpio_lock_class;
> +
> +int __init mxc_gpio_init(struct mxc_gpio_port *port, int cnt)
> +{
> +	int i, j;
> +
> +	/* save for local usage */
> +	mxc_gpio_ports = port;
> +	gpio_table_size = cnt;
> +
> +	printk(KERN_INFO "MXC GPIO hardware\n");
> +
> +	for (i = 0; i < cnt; i++) {
> +		/* disable the interrupt and clear the status */
> +		__raw_writel(0, port[i].base + GPIO_IMR);
> +		__raw_writel(~0, port[i].base + GPIO_ISR);
> +		for (j = port[i].virtual_irq_start;
> +			j < port[i].virtual_irq_start + 32; j++) {
> +			irq_set_lockdep_class(j, &gpio_lock_class);
> +			irq_set_chip_and_handler(j, &gpio_irq_chip,
> +						 handle_level_irq);
> +			set_irq_flags(j, IRQF_VALID);
> +		}
> +
> +		/* register gpio chip */
> +		port[i].chip.direction_input = mxc_gpio_direction_input;
> +		port[i].chip.direction_output = mxc_gpio_direction_output;
> +		port[i].chip.get = mxc_gpio_get;
> +		port[i].chip.set = mxc_gpio_set;
> +		port[i].chip.base = i * 32;
> +		port[i].chip.ngpio = 32;
> +
> +		spin_lock_init(&port[i].lock);
> +
> +		/* its a serious configuration bug when it fails */
> +		BUG_ON( gpiochip_add(&port[i].chip) < 0 );
> +
> +		if (cpu_is_mx1() || cpu_is_mx3() || cpu_is_mx25() || cpu_is_mx51()) {
> +			/* setup one handler for each entry */
> +			irq_set_chained_handler(port[i].irq,
> +						mx3_gpio_irq_handler);
> +			irq_set_handler_data(port[i].irq, &port[i]);
> +			if (port[i].irq_high) {
> +				/* setup handler for GPIO 16 to 31 */
> +				irq_set_chained_handler(port[i].irq_high,
> +							mx3_gpio_irq_handler);
> +				irq_set_handler_data(port[i].irq_high,
> +						     &port[i]);
> +			}
> +		}
> +	}
> +
> +	if (cpu_is_mx2()) {
> +		/* setup one handler for all GPIO interrupts */
> +		irq_set_chained_handler(port[0].irq, mx2_gpio_irq_handler);
> +		irq_set_handler_data(port[0].irq, port);
> +	}
> +
> +	return 0;
> +}
> -- 
> 1.7.4.1
>