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-rw-r--r--arch/arm/mach-mxc91231/iomux.c177
1 files changed, 177 insertions, 0 deletions
diff --git a/arch/arm/mach-mxc91231/iomux.c b/arch/arm/mach-mxc91231/iomux.c
new file mode 100644
index 0000000..405d9b1
--- /dev/null
+++ b/arch/arm/mach-mxc91231/iomux.c
@@ -0,0 +1,177 @@
+/*
+ * 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/module.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <mach/hardware.h>
+#include <mach/gpio.h>
+#include <mach/iomux-mxc91231.h>
+
+/*
+ * IOMUX register (base) addresses
+ */
+#define IOMUX_AP_BASE MXC91231_IO_ADDRESS(MXC91231_IOMUX_AP_BASE_ADDR)
+#define IOMUX_COM_BASE MXC91231_IO_ADDRESS(MXC91231_IOMUX_COM_BASE_ADDR)
+#define IOMUXSW_AP_MUX_CTL (IOMUX_AP_BASE + 0x000)
+#define IOMUXSW_SP_MUX_CTL (IOMUX_COM_BASE + 0x000)
+#define IOMUXSW_PAD_CTL (IOMUX_COM_BASE + 0x200)
+
+#define IOMUXINT_OBS1 (IOMUX_AP_BASE + 0x600)
+#define IOMUXINT_OBS2 (IOMUX_AP_BASE + 0x004)
+
+static DEFINE_SPINLOCK(gpio_mux_lock);
+
+#define NB_PORTS ((PIN_MAX + 32) / 32)
+#define PIN_GLOBAL_NUM(pin) \
+ (((pin & MUX_SIDE_MASK) >> MUX_SIDE_SHIFT)*PIN_AP_MAX + \
+ ((pin & MUX_REG_MASK) >> MUX_REG_SHIFT)*4 + \
+ ((pin & MUX_FIELD_MASK) >> MUX_FIELD_SHIFT))
+
+unsigned long mxc_pin_alloc_map[NB_PORTS * 32 / BITS_PER_LONG];
+/*
+ * set the mode for a IOMUX pin.
+ */
+int mxc_iomux_mode(const unsigned int pin_mode)
+{
+ u32 side, field, l, mode, ret = 0;
+ void __iomem *reg;
+
+ side = (pin_mode & MUX_SIDE_MASK) >> MUX_SIDE_SHIFT;
+ switch (side) {
+ case MUX_SIDE_AP:
+ reg = IOMUXSW_AP_MUX_CTL;
+ break;
+ case MUX_SIDE_SP:
+ reg = IOMUXSW_SP_MUX_CTL;
+ break;
+ default:
+ return -EINVAL;
+ }
+ reg += ((pin_mode & MUX_REG_MASK) >> MUX_REG_SHIFT) * 4;
+ field = (pin_mode & MUX_FIELD_MASK) >> MUX_FIELD_SHIFT;
+ mode = (pin_mode & MUX_MODE_MASK) >> MUX_MODE_SHIFT;
+
+ spin_lock(&gpio_mux_lock);
+
+ l = __raw_readl(reg);
+ l &= ~(0xff << (field * 8));
+ l |= mode << (field * 8);
+ __raw_writel(l, reg);
+
+ spin_unlock(&gpio_mux_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL(mxc_iomux_mode);
+
+/*
+ * This function configures the pad value for a IOMUX pin.
+ */
+void mxc_iomux_set_pad(enum iomux_pins pin, u32 config)
+{
+ u32 padgrp, field, l;
+ void __iomem *reg;
+
+ padgrp = (pin & MUX_PADGRP_MASK) >> MUX_PADGRP_SHIFT;
+ 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 = __raw_readl(reg);
+ l &= ~(0x1ff << (field * 10));
+ l |= config << (field * 10);
+ __raw_writel(l, reg);
+
+ spin_unlock(&gpio_mux_lock);
+}
+EXPORT_SYMBOL(mxc_iomux_set_pad);
+
+/*
+ * 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(const unsigned int pin_mode, const char *label)
+{
+ unsigned pad = PIN_GLOBAL_NUM(pin_mode);
+ if (pad >= (PIN_MAX + 1)) {
+ printk(KERN_ERR "mxc_iomux: Attempt to request nonexistant 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_mode);
+
+ return 0;
+}
+EXPORT_SYMBOL(mxc_iomux_alloc_pin);
+
+int mxc_iomux_setup_multiple_pins(unsigned int *pin_list, unsigned count,
+ const char *label)
+{
+ 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;
+}
+EXPORT_SYMBOL(mxc_iomux_setup_multiple_pins);
+
+void mxc_iomux_release_pin(const unsigned int pin_mode)
+{
+ unsigned pad = PIN_GLOBAL_NUM(pin_mode);
+
+ if (pad < (PIN_MAX + 1))
+ clear_bit(pad, mxc_pin_alloc_map);
+}
+EXPORT_SYMBOL(mxc_iomux_release_pin);
+
+void mxc_iomux_release_multiple_pins(unsigned int *pin_list, int count)
+{
+ unsigned int *p = pin_list;
+ int i;
+
+ for (i = 0; i < count; i++) {
+ mxc_iomux_release_pin(*p);
+ p++;
+ }
+}
+EXPORT_SYMBOL(mxc_iomux_release_multiple_pins);
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