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+/*
+ * DaVinci pinmux functions.
+ *
+ * Copyright (C) 2009 Nick Thompson, GE Fanuc Ltd, <nick.thompson@gefanuc.com>
+ * Copyright (C) 2007 Sergey Kubushyn <ksi@koi8.net>
+ * Copyright (C) 2008 Lyrtech <www.lyrtech.com>
+ * Copyright (C) 2004 Texas Instruments.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <common.h>
+#include <asm/arch/hardware.h>
+#include <asm/io.h>
+#include <asm/arch/davinci_misc.h>
+
+/*
+ * Change the setting of a pin multiplexer field.
+ *
+ * Takes an array of pinmux settings similar to:
+ *
+ * struct pinmux_config uart_pins[] = {
+ * { &davinci_syscfg_regs->pinmux[8], 2, 7 },
+ * { &davinci_syscfg_regs->pinmux[9], 2, 0 }
+ * };
+ *
+ * Stepping through the array, each pinmux[n] register has the given value
+ * set in the pin mux field specified.
+ *
+ * The number of pins in the array must be passed (ARRAY_SIZE can provide
+ * this value conveniently).
+ *
+ * Returns 0 if all field numbers and values are in the correct range,
+ * else returns -1.
+ */
+int davinci_configure_pin_mux(const struct pinmux_config *pins,
+ const int n_pins)
+{
+ int i;
+
+ /* check for invalid pinmux values */
+ for (i = 0; i < n_pins; i++) {
+ if (pins[i].field >= PIN_MUX_NUM_FIELDS ||
+ (pins[i].value & ~PIN_MUX_FIELD_MASK) != 0)
+ return -1;
+ }
+
+ /* configure the pinmuxes */
+ for (i = 0; i < n_pins; i++) {
+ const int offset = pins[i].field * PIN_MUX_FIELD_SIZE;
+ const unsigned int value = pins[i].value << offset;
+ const unsigned int mask = PIN_MUX_FIELD_MASK << offset;
+ const dv_reg *mux = pins[i].mux;
+
+ writel(value | (readl(mux) & (~mask)), mux);
+ }
+
+ return 0;
+}
+
+/*
+ * Configure multiple pinmux resources.
+ *
+ * Takes an pinmux_resource array of pinmux_config and pin counts:
+ *
+ * const struct pinmux_resource pinmuxes[] = {
+ * PINMUX_ITEM(uart_pins),
+ * PINMUX_ITEM(i2c_pins),
+ * };
+ *
+ * The number of items in the array must be passed (ARRAY_SIZE can provide
+ * this value conveniently).
+ *
+ * Each item entry is configured in the defined order. If configuration
+ * of any item fails, -1 is returned and none of the following items are
+ * configured. On success, 0 is returned.
+ */
+int davinci_configure_pin_mux_items(const struct pinmux_resource *item,
+ const int n_items)
+{
+ int i;
+
+ for (i = 0; i < n_items; i++) {
+ if (davinci_configure_pin_mux(item[i].pins,
+ item[i].n_pins) != 0)
+ return -1;
+ }
+
+ return 0;
+}
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