/* * 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> * * 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/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); }