gpio.c

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/*
 *  linux/arch/h8300/kernel/gpio.c
 *
 *  Yoshinori Sato <[email protected]>
 *
 */

/*
 * Internal I/O Port Management
 */

#include <linux/stddef.h>
#include <linux/proc_fs.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/init.h>

#define _(addr) (volatile unsigned char *)(addr)
#if defined(CONFIG_H83007) || defined(CONFIG_H83068)
#include <asm/regs306x.h>
static volatile unsigned char *ddrs[] = {
    _(P1DDR),_(P2DDR),_(P3DDR),_(P4DDR),_(P5DDR),_(P6DDR),
    NULL,    _(P8DDR),_(P9DDR),_(PADDR),_(PBDDR),
};
#define MAX_PORT 11
#endif

 #if defined(CONFIG_H83002) || defined(CONFIG_H8048)
/* Fix me!! */
#include <asm/regs306x.h>
static volatile unsigned char *ddrs[] = {
    _(P1DDR),_(P2DDR),_(P3DDR),_(P4DDR),_(P5DDR),_(P6DDR),
    NULL,    _(P8DDR),_(P9DDR),_(PADDR),_(PBDDR),
};
#define MAX_PORT 11
#endif

#if defined(CONFIG_H8S2678)
#include <asm/regs267x.h>
static volatile unsigned char *ddrs[] = {
    _(P1DDR),_(P2DDR),_(P3DDR),NULL    ,_(P5DDR),_(P6DDR),
    _(P7DDR),_(P8DDR),NULL,    _(PADDR),_(PBDDR),_(PCDDR),
    _(PDDDR),_(PEDDR),_(PFDDR),_(PGDDR),_(PHDDR),
    _(PADDR),_(PBDDR),_(PCDDR),_(PDDDR),_(PEDDR),_(PFDDR),
    _(PGDDR),_(PHDDR)
};
#define MAX_PORT 17
#endif
#undef _
 
#if !defined(P1DDR)
#error Unsuppoted CPU Selection
#endif

static struct {
    unsigned char used;
    unsigned char ddr;
} gpio_regs[MAX_PORT];

extern char *_platform_gpio_table(int length);

int h8300_reserved_gpio(int port, unsigned int bits)
{
    unsigned char *used;

    if (port < 0 || port >= MAX_PORT)
        return -1;
    used = &(gpio_regs[port].used);
    if ((*used & bits) != 0)
        return 0;
    *used |= bits;
    return 1;
}

int h8300_free_gpio(int port, unsigned int bits)
{
    unsigned char *used;

    if (port < 0 || port >= MAX_PORT)
        return -1;
    used = &(gpio_regs[port].used);
    if ((*used & bits) != bits)
        return 0;
    *used &= (~bits);
    return 1;
}

int h8300_set_gpio_dir(int port_bit,int dir)
{
    int port = (port_bit >> 8) & 0xff;
    int bit  = port_bit & 0xff;

    if (ddrs[port] == NULL)
        return 0;
    if (gpio_regs[port].used & bit) {
        if (dir)
            gpio_regs[port].ddr |= bit;
        else
            gpio_regs[port].ddr &= ~bit;
        *ddrs[port] = gpio_regs[port].ddr;
        return 1;
    } else
        return 0;
}

int h8300_get_gpio_dir(int port_bit)
{
    int port = (port_bit >> 8) & 0xff;
    int bit  = port_bit & 0xff;

    if (ddrs[port] == NULL)
        return 0;
    if (gpio_regs[port].used & bit) {
        return (gpio_regs[port].ddr & bit) != 0;
    } else
        return -1;
}

#if defined(CONFIG_PROC_FS)
static char *port_status(int portno)
{
    static char result[10];
    static const char io[2]={'I','O'};
    char *rp;
    int c;
    unsigned char used,ddr;
    
    used = gpio_regs[portno].used;
    ddr  = gpio_regs[portno].ddr;
    result[8]='\0';
    rp = result + 7;
    for (c = 8; c > 0; c--,rp--,used >>= 1, ddr >>= 1)
        if (used & 0x01)
            *rp = io[ ddr & 0x01];
        else    
            *rp = '-';
    return result;
}

static int gpio_proc_read(char *buf, char **start, off_t offset, 
                          int len, int *unused_i, void *unused_v)
{
    int c,outlen;
    static const char port_name[]="123456789ABCDEFGH";
    outlen = 0;
    for (c = 0; c < MAX_PORT; c++) {
        if (ddrs[c] == NULL)
            continue ;
        len = sprintf(buf,"P%c: %s\n",port_name[c],port_status(c));
        buf += len;
        outlen += len;
    }
    return outlen;
}

static __init int register_proc(void)
{
    struct proc_dir_entry *proc_gpio;

    proc_gpio = create_proc_entry("gpio", S_IRUGO, NULL);
    if (proc_gpio) 
        proc_gpio->read_proc = gpio_proc_read;
    return proc_gpio != NULL;
}

__initcall(register_proc);
#endif

void __init h8300_gpio_init(void)
{
    memcpy(gpio_regs,_platform_gpio_table(sizeof(gpio_regs)),sizeof(gpio_regs));
}