linux/arch/arm/mach-imx/iomux-imx31.c

162 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2004-2006 Freescale Semiconductor, Inc. All Rights Reserved.
* Copyright (C) 2008 by Sascha Hauer <kernel@pengutronix.de>
* Copyright (C) 2009 by Valentin Longchamp <valentin.longchamp@epfl.ch>
*/
#include <linux/gpio.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include "hardware.h"
#include "iomux-mx3.h"
/*
* IOMUX register (base) addresses
*/
#define IOMUX_BASE MX31_IO_ADDRESS(MX31_IOMUXC_BASE_ADDR)
#define IOMUXINT_OBS1 (IOMUX_BASE + 0x000)
#define IOMUXINT_OBS2 (IOMUX_BASE + 0x004)
#define IOMUXGPR (IOMUX_BASE + 0x008)
#define IOMUXSW_MUX_CTL (IOMUX_BASE + 0x00C)
#define IOMUXSW_PAD_CTL (IOMUX_BASE + 0x154)
static DEFINE_SPINLOCK(gpio_mux_lock);
#define IOMUX_REG_MASK (IOMUX_PADNUM_MASK & ~0x3)
static DECLARE_BITMAP(mxc_pin_alloc_map, NB_PORTS * 32);
/*
* set the mode for a IOMUX pin.
*/
void mxc_iomux_mode(unsigned int pin_mode)
{
u32 field;
u32 l;
u32 mode;
void __iomem *reg;
reg = IOMUXSW_MUX_CTL + (pin_mode & IOMUX_REG_MASK);
field = pin_mode & 0x3;
mode = (pin_mode & IOMUX_MODE_MASK) >> IOMUX_MODE_SHIFT;
spin_lock(&gpio_mux_lock);
l = imx_readl(reg);
l &= ~(0xff << (field * 8));
l |= mode << (field * 8);
imx_writel(l, reg);
spin_unlock(&gpio_mux_lock);
}
/*
* This function configures the pad value for a IOMUX pin.
*/
void mxc_iomux_set_pad(enum iomux_pins pin, u32 config)
{
u32 field, l;
void __iomem *reg;
pin &= IOMUX_PADNUM_MASK;
reg = IOMUXSW_PAD_CTL + (pin + 2) / 3 * 4;
field = (pin + 2) % 3;
pr_debug("%s: reg offset = 0x%x, field = %d\n",
__func__, (pin + 2) / 3, field);
spin_lock(&gpio_mux_lock);
l = imx_readl(reg);
l &= ~(0x1ff << (field * 10));
l |= config << (field * 10);
imx_writel(l, reg);
spin_unlock(&gpio_mux_lock);
}
/*
* allocs a single pin:
* - reserves the pin so that it is not claimed by another driver
* - setups the iomux according to the configuration
*/
int mxc_iomux_alloc_pin(unsigned int pin, const char *label)
{
unsigned pad = pin & IOMUX_PADNUM_MASK;
if (pad >= (PIN_MAX + 1)) {
printk(KERN_ERR "mxc_iomux: Attempt to request nonexistent pin %u for \"%s\"\n",
pad, label ? label : "?");
return -EINVAL;
}
if (test_and_set_bit(pad, mxc_pin_alloc_map)) {
printk(KERN_ERR "mxc_iomux: pin %u already used. Allocation for \"%s\" failed\n",
pad, label ? label : "?");
return -EBUSY;
}
mxc_iomux_mode(pin);
return 0;
}
int mxc_iomux_setup_multiple_pins(const unsigned int *pin_list, unsigned count,
const char *label)
{
const unsigned int *p = pin_list;
int i;
int ret = -EINVAL;
for (i = 0; i < count; i++) {
ret = mxc_iomux_alloc_pin(*p, label);
if (ret)
goto setup_error;
p++;
}
return 0;
setup_error:
mxc_iomux_release_multiple_pins(pin_list, i);
return ret;
}
void mxc_iomux_release_pin(unsigned int pin)
{
unsigned pad = pin & IOMUX_PADNUM_MASK;
if (pad < (PIN_MAX + 1))
clear_bit(pad, mxc_pin_alloc_map);
}
void mxc_iomux_release_multiple_pins(const unsigned int *pin_list, int count)
{
const unsigned int *p = pin_list;
int i;
for (i = 0; i < count; i++) {
mxc_iomux_release_pin(*p);
p++;
}
}
/*
* This function enables/disables the general purpose function for a particular
* signal.
*/
void mxc_iomux_set_gpr(enum iomux_gp_func gp, bool en)
{
u32 l;
spin_lock(&gpio_mux_lock);
l = imx_readl(IOMUXGPR);
if (en)
l |= gp;
else
l &= ~gp;
imx_writel(l, IOMUXGPR);
spin_unlock(&gpio_mux_lock);
}