[wip:20140511] uchcom.c diff (worked, 9600bps only!)

--- uchcom.c.bak	Fri Nov 15 19:17:39 2013
+++ uchcom.c	Sun May 11 06:15:20 2014
@@ -48,9 +48,10 @@
 #include <dev/usb/usbdevs.h>
 #include <dev/usb/ucomvar.h>

+#define UCHCOM_DEBUG
 #ifdef UCHCOM_DEBUG
 #define DPRINTFN(n, x)  do { if (uchcomdebug > (n)) printf x; } while (0)
-int	uchcomdebug = 0;
+int	uchcomdebug = 3;
 #else
 #define DPRINTFN(n, x)
 #endif
@@ -72,7 +73,7 @@ int	uchcomdebug = 0;
 #define UCHCOM_REG_STAT2	0x07
 #define UCHCOM_REG_BPS_PRE	0x12
 #define UCHCOM_REG_BPS_DIV	0x13
-#define UCHCOM_REG_BPS_MOD	0x14
+#define UCHCOM_REG_BPS_MOD	0x2C
 #define UCHCOM_REG_BPS_PAD	0x0F
 #define UCHCOM_REG_BREAK1	0x05
 #define UCHCOM_REG_BREAK2	0x18
@@ -81,9 +82,8 @@ int	uchcomdebug = 0;

 #define UCHCOM_VER_20		0x20

-#define UCHCOM_BASE_UNKNOWN	0
-#define UCHCOM_BPS_MOD_BASE	20000000
-#define UCHCOM_BPS_MOD_BASE_OFS	1100
+#define	UCHCOM_BAUDBASE_FACTOR	1532620800
+#define	UCHCOM_BAUDBASE_DIVMAX	3

 #define UCHCOM_DTR_MASK		0x20
 #define UCHCOM_RTS_MASK		0x40
@@ -142,24 +142,6 @@ struct uchcom_divider
 	uint8_t		dv_mod;
 };

-struct uchcom_divider_record
-{
-	uint32_t		dvr_high;
-	uint32_t		dvr_low;
-	uint32_t		dvr_base_clock;
-	struct uchcom_divider	dvr_divider;
-};
-
-static const struct uchcom_divider_record dividers[] =
-{
-	{  307200, 307200, UCHCOM_BASE_UNKNOWN, { 7, 0xD9, 0 } },
-	{  921600, 921600, UCHCOM_BASE_UNKNOWN, { 7, 0xF3, 0 } },
-	{ 2999999,  23530,             6000000, { 3,    0, 0 } },
-	{   23529,   2942,              750000, { 2,    0, 0 } },
-	{    2941,    368,               93750, { 1,    0, 0 } },
-	{     367,      1,               11719, { 0,    0, 0 } },
-};
-
 void		uchcom_get_status(void *, int, u_char *, u_char *);
 void		uchcom_set(void *, int, int, int);
 int		uchcom_param(void *, int, struct termios *);
@@ -259,6 +241,7 @@ uchcom_attach(struct device *parent, struct device *se
 	struct ucom_attach_args uca;
 	struct usbd_device *dev = uaa->device;
 	struct uchcom_endpoints endpoints;
+	usbd_status err;

         sc->sc_udev = dev;
 	sc->sc_dtr = sc->sc_rts = -1;
@@ -300,7 +283,15 @@ uchcom_attach(struct device *parent, struct device *se
 	uca.methods = &uchcom_methods;
 	uca.arg = sc;
 	uca.info = NULL;
-
+
+	err = uchcom_setup_comm(sc);
+	if (err) {
+		printf("%s: setup failed, %s\n", sc->sc_dev.dv_xname,
+		       usbd_errstr(err));
+		usbd_deactivate(sc->sc_udev);
+		return;
+	}
+
 	sc->sc_subdev = config_found_sm(self, &uca, ucomprint, ucomsubmatch);

 	return;
@@ -645,39 +636,26 @@ uchcom_set_break(struct uchcom_softc *sc, int onoff)
 int
 uchcom_calc_divider_settings(struct uchcom_divider *dp, uint32_t rate)
 {
-	int i;
-	const struct uchcom_divider_record *rp;
-	uint32_t div, rem, mod;
+	uint32_t factor, prescaler;

-	/* find record */
-	for (i=0; i<nitems(dividers); i++) {
-		if (dividers[i].dvr_high >= rate &&
-		    dividers[i].dvr_low <= rate) {
-			rp = &dividers[i];
-			goto found;
-		}
-	}
-	return -1;
+	if (!rate)
+		return -1;

-found:
-	dp->dv_prescaler = rp->dvr_divider.dv_prescaler;
-	if (rp->dvr_base_clock == UCHCOM_BASE_UNKNOWN)
-		dp->dv_div = rp->dvr_divider.dv_div;
-	else {
-		div = rp->dvr_base_clock / rate;
-		rem = rp->dvr_base_clock % rate;
-		if (div==0 || div>=0xFF)
-			return -1;
-		if ((rem<<1) >= rate)
-			div += 1;
-		dp->dv_div = (uint8_t)-div;
+	factor = UCHCOM_BAUDBASE_FACTOR / rate;
+	prescaler = UCHCOM_BAUDBASE_DIVMAX;
+
+	while ((factor > 0xfff0) && prescaler) {
+		factor >>= 3;
+		prescaler--;
 	}
+	if (factor > 0xfff0)
+		return -1;

-	mod = UCHCOM_BPS_MOD_BASE/rate + UCHCOM_BPS_MOD_BASE_OFS;
-	mod = mod + mod/2;
+	factor = 0x10000 - factor;
+	dp->dv_prescaler = prescaler;
+	dp->dv_div = (factor & 0xff00) >> 8;
+	dp->dv_mod = factor & 0xff;

-	dp->dv_mod = mod / 0x100;
-
 	return 0;
 }

@@ -859,6 +837,10 @@ uchcom_setup_comm(struct uchcom_softc *sc)
 	if (ret)
 		return ret;

+	ret = uchcom_read_status(sc, NULL);
+	if (ret)
+		return ret;
+
 	return 0;
 }

@@ -949,7 +931,7 @@ uchcom_param(void *arg, int portno, struct termios *t)
 {
 	struct uchcom_softc *sc = arg;
 	int ret;
-
+return 0; // XXX
 	if (usbd_is_dying(sc->sc_udev))
 		return 0;