TI Davinci: add a pin multiplexer configuration API

Creates a method allowing pin settings to be logically grouped into data
structure arrays and provides an API to configure the pinmux settings to
enable the relevant pin functions.

Signed-off-by: Nick Thompson <nick.thompson@gefanuc.com>
This commit is contained in:
Nick Thompson 2009-11-12 11:03:23 -05:00 committed by Tom Rix
parent 9868a36dfb
commit ca8480d444
2 changed files with 59 additions and 1 deletions

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@ -1,6 +1,7 @@
/*
* Miscelaneous DaVinci 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.
@ -27,7 +28,8 @@
#include <i2c.h>
#include <net.h>
#include <asm/arch/hardware.h>
#include <asm/io.h>
#include "misc.h"
DECLARE_GLOBAL_DATA_PTR;
@ -109,3 +111,47 @@ void dv_configure_mac_address(uint8_t *rom_enetaddr)
}
#endif /* DAVINCI_EMAC */
/*
* 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;
}

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@ -22,8 +22,20 @@
#ifndef __MISC_H
#define __MISC_H
/* pin muxer definitions */
#define PIN_MUX_NUM_FIELDS 8 /* Per register */
#define PIN_MUX_FIELD_SIZE 4 /* n in bits */
#define PIN_MUX_FIELD_MASK ((1 << PIN_MUX_FIELD_SIZE) - 1)
/* pin definition */
struct pinmux_config {
dv_reg *mux; /* Address of mux register */
unsigned char value; /* Value to set in field */
unsigned char field; /* field number */
};
int dvevm_read_mac_address(uint8_t *buf);
void dv_configure_mac_address(uint8_t *rom_enetaddr);
int davinci_configure_pin_mux(const struct pinmux_config *pins, int n_pins);
#endif /* __MISC_H */