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#include "u.h"
#include "../port/lib.h"
#include "../port/error.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
/* gpio registers */
enum {
GPIO_DR = 0x00/4,
GPIO_GDIR = 0x04/4,
GPIO_PSR = 0x08/4,
GPIO_ICR1 = 0x0C/4,
GPIO_ICR2 = 0x10/4,
GPIO_IMR = 0x14/4,
GPIO_ISR = 0x18/4,
GPIO_EDGE_SEL = 0x1C/4,
};
typedef struct Ctlr Ctlr;
struct Ctlr
{
u32int *reg;
char *clk;
u32int dir;
int enabled;
};
static Ctlr ctlrs[5] = {
{(u32int*)(VIRTIO + 0x200000), "gpio1.ipg_clk_s" },
{(u32int*)(VIRTIO + 0x210000), "gpio2.ipg_clk_s" },
{(u32int*)(VIRTIO + 0x220000), "gpio3.ipg_clk_s" },
{(u32int*)(VIRTIO + 0x230000), "gpio4.ipg_clk_s" },
{(u32int*)(VIRTIO + 0x240000), "gpio5.ipg_clk_s" },
};
static Ctlr*
enable(uint pin)
{
Ctlr *ctlr;
pin /= 32;
if(pin < 1 || pin > nelem(ctlrs))
return nil;
ctlr = &ctlrs[pin-1];
if(!ctlr->enabled){
setclkgate(ctlr->clk, 1);
ctlr->reg[GPIO_IMR] = 0;
ctlr->dir = ctlr->reg[GPIO_GDIR];
ctlr->enabled = 1;
}
return ctlr;
}
void
gpioout(uint pin, int set)
{
u32int bit = 1 << (pin % 32);
Ctlr *ctlr = enable(pin);
if(ctlr == nil)
return;
if((ctlr->dir & bit) == 0)
ctlr->reg[GPIO_GDIR] = ctlr->dir |= bit;
if(set)
ctlr->reg[GPIO_DR] |= bit;
else
ctlr->reg[GPIO_DR] &= ~bit;
}
int
gpioin(uint pin)
{
u32int bit = 1 << (pin % 32);
Ctlr *ctlr = enable(pin);
if(ctlr == nil)
return -1;
if(ctlr->dir & bit)
ctlr->reg[GPIO_GDIR] = ctlr->dir &= ~bit;
return (ctlr->reg[GPIO_DR] & bit) != 0;
}
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