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Diffstat (limited to 'arch/arm/mach-davinci/pinmux.c')
-rw-r--r-- | arch/arm/mach-davinci/pinmux.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/pinmux.c b/arch/arm/mach-davinci/pinmux.c new file mode 100644 index 0000000..e9d8c87 --- /dev/null +++ b/arch/arm/mach-davinci/pinmux.c @@ -0,0 +1,90 @@ +/* + * 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. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#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; +} |