u-boot/drivers/gpio/at91_gpio.c

/*
 * Memory Setup stuff - taken from blob memsetup.S
 *
 * Copyright (C) 2009 Jens Scharsig (js_at_ng@scharsoft.de)
 *
 *  Copyright (C) 2005 HP Labs
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * 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., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

/*
 * WARNING:
 *
 * As the code is right now, it expects all PIO ports A,B,C,...
 * to be evenly spaced in the memory map:
 * ATMEL_BASE_PIOA + port * sizeof at91pio_t
 * This might not necessaryly be true in future Atmel SoCs.
 * This code should be fixed to use a pointer array to the ports.
 */

#include <config.h>
#include <common.h>
#include <asm/io.h>
#include <asm/sizes.h>
#include <asm/arch/hardware.h>
#include <asm/arch/at91_pio.h>

int at91_set_pio_pullup(unsigned port, unsigned pin, int use_pullup)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		if (use_pullup)
			writel(1 << pin, &pio->port[port].puer);
		else
			writel(1 << pin, &pio->port[port].pudr);
		writel(mask, &pio->port[port].per);
	}
	return 0;
}

/*
 * mux the pin to the "GPIO" peripheral role.
 */
int at91_set_pio_periph(unsigned port, unsigned pin, int use_pullup)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		writel(mask, &pio->port[port].idr);
		at91_set_pio_pullup(port, pin, use_pullup);
		writel(mask, &pio->port[port].per);
	}
	return 0;
}

/*
 * mux the pin to the "A" internal peripheral role.
 */
int at91_set_a_periph(unsigned port, unsigned pin, int use_pullup)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		writel(mask, &pio->port[port].idr);
		at91_set_pio_pullup(port, pin, use_pullup);
		writel(mask, &pio->port[port].asr);
		writel(mask, &pio->port[port].pdr);
	}
	return 0;
}

/*
 * mux the pin to the "B" internal peripheral role.
 */
int at91_set_b_periph(unsigned port, unsigned pin, int use_pullup)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		writel(mask, &pio->port[port].idr);
		at91_set_pio_pullup(port, pin, use_pullup);
		writel(mask, &pio->port[port].bsr);
		writel(mask, &pio->port[port].pdr);
	}
	return 0;
}

/*
 * mux the pin to the gpio controller (instead of "A" or "B" peripheral), and
 * configure it for an input.
 */
int at91_set_pio_input(unsigned port, u32 pin, int use_pullup)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		writel(mask, &pio->port[port].idr);
		at91_set_pio_pullup(port, pin, use_pullup);
		writel(mask, &pio->port[port].odr);
		writel(mask, &pio->port[port].per);
	}
	return 0;
}

/*
 * mux the pin to the gpio controller (instead of "A" or "B" peripheral),
 * and configure it for an output.
 */
int at91_set_pio_output(unsigned port, u32 pin, int value)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		writel(mask, &pio->port[port].idr);
		writel(mask, &pio->port[port].pudr);
		if (value)
			writel(mask, &pio->port[port].sodr);
		else
			writel(mask, &pio->port[port].codr);
		writel(mask, &pio->port[port].oer);
		writel(mask, &pio->port[port].per);
	}
	return 0;
}

/*
 * enable/disable the glitch filter. mostly used with IRQ handling.
 */
int at91_set_pio_deglitch(unsigned port, unsigned pin, int is_on)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		if (is_on)
			writel(mask, &pio->port[port].ifer);
		else
			writel(mask, &pio->port[port].ifdr);
	}
	return 0;
}

/*
 * enable/disable the multi-driver. This is only valid for output and
 * allows the output pin to run as an open collector output.
 */
int at91_set_pio_multi_drive(unsigned port, unsigned pin, int is_on)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		if (is_on)
			writel(mask, &pio->port[port].mder);
		else
			writel(mask, &pio->port[port].mddr);
	}
	return 0;
}

/*
 * assuming the pin is muxed as a gpio output, set its value.
 */
int at91_set_pio_value(unsigned port, unsigned pin, int value)
{
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		if (value)
			writel(mask, &pio->port[port].sodr);
		else
			writel(mask, &pio->port[port].codr);
	}
	return 0;
}

/*
 * read the pin's value (works even if it's not muxed as a gpio).
 */
int at91_get_pio_value(unsigned port, unsigned pin)
{
	u32		pdsr = 0;
	at91_pio_t	*pio = (at91_pio_t *) ATMEL_BASE_PIOA;
	u32		mask;

	if ((port < ATMEL_PIO_PORTS) && (pin < 32)) {
		mask = 1 << pin;
		pdsr = readl(&pio->port[port].pdsr) & mask;
	}
	return pdsr != 0;
}