mspdebug/simio_gpio.c

369 lines
7.6 KiB
C

/* MSPDebug - debugging tool for MSP430 MCUs
* Copyright (C) 2009, 2010 Daniel Beer
*
* This program is free software; you can redisgibute 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 disgibuted 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdlib.h>
#include <string.h>
#include "simio_device.h"
#include "simio_gpio.h"
#include "expr.h"
#include "output.h"
#define REG_IN 0
#define REG_OUT 1
#define REG_DIR 2
#define REG_IFG 3
#define REG_IES 4
#define REG_IE 5
#define REG_SEL 6
#define REG_REN 7
struct gpio {
struct simio_device base;
/* Print when output changes? */
int verbose;
/* Base address */
address_t base_addr;
/* IRQ, or -1 if disabled */
int irq;
/* Congol registers */
uint8_t regs[8];
};
static struct simio_device *gpio_create(char **arg_text)
{
struct gpio *g;
g = malloc(sizeof(*g));
if (!g) {
pr_error("gpio: can't allocate memory");
return NULL;
}
memset(g, 0, sizeof(*g));
g->base.type = &simio_gpio;
g->base_addr = 0x20;
g->irq = -1;
return (struct simio_device *)g;
}
static void gpio_destroy(struct simio_device *dev)
{
struct gpio *g = (struct gpio *)dev;
free(g);
}
static void gpio_reset(struct simio_device *dev)
{
struct gpio *g = (struct gpio *)dev;
g->regs[REG_DIR] = 0;
g->regs[REG_IFG] = 0;
g->regs[REG_IE] = 0;
g->regs[REG_SEL] = 0;
g->regs[REG_REN] = 0;
}
static int config_addr(address_t *addr, char **arg_text)
{
char *text = get_arg(arg_text);
if (!text) {
printc_err("gpio: config: expected address\n");
return -1;
}
if (expr_eval(text, addr) < 0) {
printc_err("gpio: can't parse address: %s\n", text);
return -1;
}
return 0;
}
static int config_irq(int *irq, char **arg_text)
{
char *text = get_arg(arg_text);
address_t value;
if (!text) {
printc_err("gpio: config: expected interrupt number\n");
return -1;
}
if (expr_eval(text, &value) < 0) {
printc_err("gpio: can't parse interrupt number: %s\n", text);
return -1;
}
*irq = value;
return 0;
}
static int config_channel(struct gpio *g, char **arg_text)
{
char *which_text = get_arg(arg_text);
char *value_text = get_arg(arg_text);
address_t which;
address_t value;
uint8_t mask;
if (!(which_text && value_text)) {
printc_err("gpio: config: expected pin and value\n");
return -1;
}
if (expr_eval(which_text, &which) < 0) {
printc_err("gpio: can't parse pin number: %s\n",
which_text);
return -1;
}
if (expr_eval(value_text, &value) < 0) {
printc_err("gpio: can't parse pin value: %s\n",
value_text);
return -1;
}
if (which < 0 || which > 7) {
printc_err("gpio: invalid pin number: %d\n", which);
return -1;
}
mask = 1 << which;
if (g->regs[REG_IE] & mask) {
if (((g->regs[REG_IES] & mask) &&
!value && (g->regs[REG_IN] & mask)) ||
(!(g->regs[REG_IES] & mask) &&
value && !(g->regs[REG_IN] & mask)))
g->regs[REG_IFG] |= mask;
}
if (value)
g->regs[REG_IN] |= mask;
else
g->regs[REG_IN] &= ~mask;
return 0;
}
static int gpio_config(struct simio_device *dev,
const char *param, char **arg_text)
{
struct gpio *g = (struct gpio *)dev;
if (!strcasecmp(param, "base"))
return config_addr(&g->base_addr, arg_text);
if (!strcasecmp(param, "irq"))
return config_irq(&g->irq, arg_text);
if (!strcasecmp(param, "set"))
return config_channel(g, arg_text);
if (!strcasecmp(param, "noirq")) {
g->irq = -1;
return 0;
}
if (!strcasecmp(param, "verbose")) {
g->verbose = 1;
return 0;
}
if (!strcasecmp(param, "quiet")) {
g->verbose = 0;
return 0;
}
printc_err("gpio: config: unknown parameter: %s\n", param);
return -1;
}
static void print_tristate(uint8_t mask, uint8_t value)
{
int i;
for (i = 0; i < 8; i++) {
if (!(mask & 0x80))
printc("-");
else if (value & 0x80)
printc("H");
else
printc("l");
if (i == 3)
printc(" ");
value <<= 1;
mask <<= 1;
}
}
static int port_map(struct gpio *g, address_t addr)
{
int ren_addr;
if (g->irq >= 0) {
if (addr < g->base_addr)
return -1;
if (addr >= g->base_addr + 8)
return -1;
return addr - g->base_addr;
}
if (addr >= g->base_addr && addr <= g->base_addr + 2)
return addr - g->base_addr;
if (addr == g->base_addr + 3)
return REG_SEL;
ren_addr = ((g->base_addr >> 2) & 1) |
((g->base_addr >> 4) & 2) | 0x10;
if (addr == ren_addr)
return REG_REN;
return -1;
}
static int gpio_info(struct simio_device *dev)
{
struct gpio *g = (struct gpio *)dev;
printc("Base address: 0x%04x\n", g->base_addr);
printc("Input state: ");
print_tristate(~g->regs[REG_DIR] & ~g->regs[REG_SEL], g->regs[REG_IN]);
printc("\n");
printc("Output state: ");
print_tristate(g->regs[REG_DIR] & ~g->regs[REG_SEL], g->regs[REG_OUT]);
printc("\n");
printc("Direction: ");
print_tristate(~g->regs[REG_SEL], g->regs[REG_DIR]);
printc("\n");
if (g->irq >= 0) {
printc("IRQ: %d\n", g->irq);
printc("Interrupt: ");
print_tristate(g->regs[REG_IE], g->regs[REG_IFG]);
printc("\n");
printc("Interrupt edge select: ");
print_tristate(g->regs[REG_IE], g->regs[REG_IES]);
printc("\n");
printc("Interrupt enable: ");
print_tristate(0xff, g->regs[REG_IE]);
printc("\n");
}
printc("Port select: ");
print_tristate(0xff, g->regs[REG_SEL]);
printc("\n");
printc("Resistor enable: ");
print_tristate(0xff, g->regs[REG_REN]);
printc("\n");
return 0;
}
static int gpio_write_b(struct simio_device *dev,
address_t addr, uint8_t data)
{
struct gpio *g = (struct gpio *)dev;
int index = port_map(g, addr);
if (index < 0)
return 1;
if (g->verbose && index == REG_OUT) {
uint8_t delta = (g->regs[REG_OUT] ^ data) &
g->regs[REG_DIR] & ~g->regs[REG_SEL];
if (delta) {
printc("gpio: state change on %s: ", g->base.name);
print_tristate(delta, data);
printc("\n");
}
}
g->regs[index] = data;
return 1;
}
static int gpio_read_b(struct simio_device *dev,
address_t addr, uint8_t *data)
{
struct gpio *g = (struct gpio *)dev;
int index = port_map(g, addr);
if (index < 0)
return 1;
if (addr < g->base_addr || index >= 8)
return 1;
*data = g->regs[index];
return 0;
}
static int gpio_check_interrupt(struct simio_device *dev)
{
struct gpio *g = (struct gpio *)dev;
if (g->regs[REG_IFG] & g->regs[REG_IE])
return g->irq;
return -1;
}
const struct simio_class simio_gpio = {
.name = "gpio",
.help =
"This peripheral implements a digital IO port, with optional interrupt\n"
"functionality.\n"
"\n"
"Config arguments are:\n"
" base <address>\n"
" Set the peripheral base address.\n"
" irq <interrupt>\n"
" Set the interrupt vector for input pin state changes.\n"
" noirq\n"
" Disable interrupt functionality.\n"
" verbose\n"
" Print a message when output states change.\n"
" quiet\n"
" Don't print messages as output state changes.\n"
" set <pin> <0|1>\n"
" Set input pin state.\n",
.create = gpio_create,
.destroy = gpio_destroy,
.reset = gpio_reset,
.config = gpio_config,
.info = gpio_info,
.write_b = gpio_write_b,
.read_b = gpio_read_b,
.check_interrupt = gpio_check_interrupt
};