20060303

1 files changed, 88 insertions, 0 deletions

diff --git a/os/pxa/gpio.c b/os/pxa/gpio.c
new file mode 100644
index 00000000..5914f8c4
--- /dev/null
+++ b/os/pxa/gpio.c
@@ -0,0 +1,88 @@
+#include	"u.h"
+#include 	"mem.h"
+#include	"../port/lib.h"
+#include 	"dat.h"
+#include	"fns.h"
+#include	"io.h"
+
+static ulong gpioreserved[3];
+static Lock gpiolock;
+
+void
+gpioreserve(int n)
+{
+	ulong mask, *r;
+
+	r = &gpioreserved[GPR(n)];
+	mask = GPB(n);
+	ilock(&gpiolock);
+	if(*r & mask)
+		panic("gpioreserve: duplicate use of GPIO %d", n);
+	*r |= mask;
+	iunlock(&gpiolock);
+}
+
+/*
+ * set direction and alternative function bits in the GPIO control register,
+ * following the configuration bits in cfg.
+ */
+void
+gpioconfig(int n, ulong cfg)
+{
+	GpioReg *g;
+	ulong o, m, *r;
+
+	m = GPB(n);
+	o = n>>5;
+	ilock(&gpiolock);
+	g = GPIOREG;
+	r = &g->gpdr[o];
+	if(cfg & Gpio_out)
+		*r |= m;
+	else
+		*r &= ~m;
+	r = &g->gafr[o*2];
+	*r = (*r & ~GPAF(n, 3)) | GPAF(n, cfg&3);
+	iunlock(&gpiolock);
+}
+
+ulong
+gpioget(int n)
+{
+	ulong mask, o;
+
+	mask = GPB(n);
+	o = GPR(n);
+	return GPIOREG->gplr[o] & mask;
+}
+
+void
+gpioset(int n, int v)
+{
+	GpioReg *g;
+	ulong mask, o;
+
+	g = GPIOREG;
+	mask = GPB(n);
+	o = GPR(n);
+	ilock(&gpiolock);
+	if(v)
+		g->gpsr[o] = mask;
+	else
+		g->gpcr[o] = mask;
+	iunlock(&gpiolock);
+}
+
+void
+gpiorelease(int n)
+{
+	ulong mask, *r;
+
+	mask = GPB(n);
+	r = &gpioreserved[GPR(n)];
+	ilock(&gpiolock);
+	if((*r & mask) != mask)
+		panic("gpiorelease: unexpected release of GPIO %d", n);
+	*r &= ~mask;
+	iunlock(&gpiolock);
+}