u-boot/drivers/gpio/at91_gpio.c
Wu, Josh 7d82d89772 gpio: at91: add sanity check for the NULL pointer
We need check the NULL pointer as at91_pio_get_port() may return NULL.

Also print a error message when at91_pio_get_port() failed otherwise we
cannot notice the failure.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
2014-05-27 00:10:45 +02:00

397 lines
8.3 KiB
C

/*
* Copyright (C) 2013 Bo Shen <voice.shen@atmel.com>
*
* Copyright (C) 2009 Jens Scharsig (js_at_ng@scharsoft.de)
*
* Copyright (C) 2005 HP Labs
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <config.h>
#include <common.h>
#include <asm/io.h>
#include <linux/sizes.h>
#include <asm/arch/hardware.h>
#include <asm/arch/at91_pio.h>
#include <asm/arch/gpio.h>
static struct at91_port *at91_pio_get_port(unsigned port)
{
switch (port) {
case AT91_PIO_PORTA:
return (struct at91_port *)ATMEL_BASE_PIOA;
case AT91_PIO_PORTB:
return (struct at91_port *)ATMEL_BASE_PIOB;
case AT91_PIO_PORTC:
return (struct at91_port *)ATMEL_BASE_PIOC;
#if (ATMEL_PIO_PORTS > 3)
case AT91_PIO_PORTD:
return (struct at91_port *)ATMEL_BASE_PIOD;
#if (ATMEL_PIO_PORTS > 4)
case AT91_PIO_PORTE:
return (struct at91_port *)ATMEL_BASE_PIOE;
#endif
#endif
default:
printf("Error: at91_gpio: Fail to get PIO base!\n");
return NULL;
}
}
int at91_set_pio_pullup(unsigned port, unsigned pin, int use_pullup)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
if (use_pullup)
writel(1 << pin, &at91_port->puer);
else
writel(1 << pin, &at91_port->pudr);
writel(mask, &at91_port->per);
}
return 0;
}
/*
* mux the pin to the "GPIO" peripheral role.
*/
int at91_set_pio_periph(unsigned port, unsigned pin, int use_pullup)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->idr);
at91_set_pio_pullup(port, pin, use_pullup);
writel(mask, &at91_port->per);
}
return 0;
}
/*
* mux the pin to the "A" internal peripheral role.
*/
int at91_set_a_periph(unsigned port, unsigned pin, int use_pullup)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->idr);
at91_set_pio_pullup(port, pin, use_pullup);
#if defined(CPU_HAS_PIO3)
writel(readl(&at91_port->abcdsr1) & ~mask,
&at91_port->abcdsr1);
writel(readl(&at91_port->abcdsr2) & ~mask,
&at91_port->abcdsr2);
#else
writel(mask, &at91_port->asr);
#endif
writel(mask, &at91_port->pdr);
}
return 0;
}
/*
* mux the pin to the "B" internal peripheral role.
*/
int at91_set_b_periph(unsigned port, unsigned pin, int use_pullup)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->idr);
at91_set_pio_pullup(port, pin, use_pullup);
#if defined(CPU_HAS_PIO3)
writel(readl(&at91_port->abcdsr1) | mask,
&at91_port->abcdsr1);
writel(readl(&at91_port->abcdsr2) & ~mask,
&at91_port->abcdsr2);
#else
writel(mask, &at91_port->bsr);
#endif
writel(mask, &at91_port->pdr);
}
return 0;
}
#if defined(CPU_HAS_PIO3)
/*
* mux the pin to the "C" internal peripheral role.
*/
int at91_set_c_periph(unsigned port, unsigned pin, int use_pullup)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->idr);
at91_set_pio_pullup(port, pin, use_pullup);
writel(readl(&at91_port->abcdsr1) & ~mask,
&at91_port->abcdsr1);
writel(readl(&at91_port->abcdsr2) | mask,
&at91_port->abcdsr2);
writel(mask, &at91_port->pdr);
}
return 0;
}
/*
* mux the pin to the "D" internal peripheral role.
*/
int at91_set_d_periph(unsigned port, unsigned pin, int use_pullup)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->idr);
at91_set_pio_pullup(port, pin, use_pullup);
writel(readl(&at91_port->abcdsr1) | mask,
&at91_port->abcdsr1);
writel(readl(&at91_port->abcdsr2) | mask,
&at91_port->abcdsr2);
writel(mask, &at91_port->pdr);
}
return 0;
}
#endif
/*
* mux the pin to the gpio controller (instead of "A" or "B" peripheral), and
* configure it for an input.
*/
int at91_set_pio_input(unsigned port, u32 pin, int use_pullup)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->idr);
at91_set_pio_pullup(port, pin, use_pullup);
writel(mask, &at91_port->odr);
writel(mask, &at91_port->per);
}
return 0;
}
/*
* mux the pin to the gpio controller (instead of "A" or "B" peripheral),
* and configure it for an output.
*/
int at91_set_pio_output(unsigned port, u32 pin, int value)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (port < ATMEL_PIO_PORTS) && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->idr);
writel(mask, &at91_port->pudr);
if (value)
writel(mask, &at91_port->sodr);
else
writel(mask, &at91_port->codr);
writel(mask, &at91_port->oer);
writel(mask, &at91_port->per);
}
return 0;
}
/*
* enable/disable the glitch filter. mostly used with IRQ handling.
*/
int at91_set_pio_deglitch(unsigned port, unsigned pin, int is_on)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
if (is_on) {
#if defined(CPU_HAS_PIO3)
writel(mask, &at91_port->ifscdr);
#endif
writel(mask, &at91_port->ifer);
} else {
writel(mask, &at91_port->ifdr);
}
}
return 0;
}
#if defined(CPU_HAS_PIO3)
/*
* enable/disable the debounce filter.
*/
int at91_set_pio_debounce(unsigned port, unsigned pin, int is_on, int div)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
if (is_on) {
writel(mask, &at91_port->ifscer);
writel(div & PIO_SCDR_DIV, &at91_port->scdr);
writel(mask, &at91_port->ifer);
} else {
writel(mask, &at91_port->ifdr);
}
}
return 0;
}
/*
* enable/disable the pull-down.
* If pull-up already enabled while calling the function, we disable it.
*/
int at91_set_pio_pulldown(unsigned port, unsigned pin, int is_on)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(mask, &at91_port->pudr);
if (is_on)
writel(mask, &at91_port->ppder);
else
writel(mask, &at91_port->ppddr);
}
return 0;
}
/*
* disable Schmitt trigger
*/
int at91_set_pio_disable_schmitt_trig(unsigned port, unsigned pin)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
writel(readl(&at91_port->schmitt) | mask,
&at91_port->schmitt);
}
return 0;
}
#endif
/*
* enable/disable the multi-driver. This is only valid for output and
* allows the output pin to run as an open collector output.
*/
int at91_set_pio_multi_drive(unsigned port, unsigned pin, int is_on)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
if (is_on)
writel(mask, &at91_port->mder);
else
writel(mask, &at91_port->mddr);
}
return 0;
}
/*
* assuming the pin is muxed as a gpio output, set its value.
*/
int at91_set_pio_value(unsigned port, unsigned pin, int value)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
if (value)
writel(mask, &at91_port->sodr);
else
writel(mask, &at91_port->codr);
}
return 0;
}
/*
* read the pin's value (works even if it's not muxed as a gpio).
*/
int at91_get_pio_value(unsigned port, unsigned pin)
{
struct at91_port *at91_port = at91_pio_get_port(port);
u32 pdsr = 0, mask;
if (at91_port && (pin < 32)) {
mask = 1 << pin;
pdsr = readl(&at91_port->pdsr) & mask;
}
return pdsr != 0;
}
/* Common GPIO API */
int gpio_request(unsigned gpio, const char *label)
{
return 0;
}
int gpio_free(unsigned gpio)
{
return 0;
}
int gpio_direction_input(unsigned gpio)
{
at91_set_pio_input(at91_gpio_to_port(gpio),
at91_gpio_to_pin(gpio), 0);
return 0;
}
int gpio_direction_output(unsigned gpio, int value)
{
at91_set_pio_output(at91_gpio_to_port(gpio),
at91_gpio_to_pin(gpio), value);
return 0;
}
int gpio_get_value(unsigned gpio)
{
return at91_get_pio_value(at91_gpio_to_port(gpio),
at91_gpio_to_pin(gpio));
}
int gpio_set_value(unsigned gpio, int value)
{
at91_set_pio_value(at91_gpio_to_port(gpio),
at91_gpio_to_pin(gpio), value);
return 0;
}