Init commit

1 files changed, 199 insertions, 0 deletions

diff --git a/usb/endpt0.c b/usb/endpt0.c
new file mode 100644
index 0000000..a60e1a4
--- /dev/null
+++ b/usb/endpt0.c
@@ -0,0 +1,199 @@
+#include <le.h>
+#include <reg/usbotg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <reg/gpio.h>
+
+#include "bdt.h"
+#include "endpt0.h"
+
+#include "ds_conf.xxh"
+#include "ds_dev.xxh"
+#include "ds_lang.xxh"
+#include "ds_str1.xxh"
+
+#define MAX_PACKET 64
+static unsigned char buf[2][MAX_PACKET];
+static bool odd;
+static bool data01;
+
+static volatile unsigned int nextaddr;
+
+static const void *tx_data;
+static size_t tx_size;
+
+struct tok_setup {
+	uint8_t reqtyp;
+	uint8_t req;
+	uint16_t value;
+	uint16_t index;
+	uint16_t length;
+};
+
+/* read_setup: parse a SETUP token's data */
+static void read_setup(struct tok_setup *setup, const void *_data)
+{
+	const unsigned char *data = _data;
+
+	setup->reqtyp = data[0];
+	setup->req = data[1];
+	setup->value = le16toh(&data[2]);
+	setup->index = le16toh(&data[4]);
+	setup->length = le16toh(&data[6]);
+}
+
+/* TODO: Make this a shared thing across all USB endpoints */
+
+/* puttx: place data in the current buffer descriptor */
+static bool puttx(const void *data, size_t size)
+{
+	if (GET_BIT(BDT_ENDPT(0, BDT_TX, odd).desc, BD_OWN))
+		return false;
+
+	BDT_ENDPT(0, BDT_TX, odd).addr = (void *)data;
+	BDT_ENDPT(0, BDT_TX, odd).desc = USB0_BD_INIT(size, data01);
+	odd = !odd;
+	data01 = !data01;
+
+	return true;
+}
+
+/* pushtx: attempt to push rest of the current transmission into a BD */
+static bool pushtx(void)
+{
+	size_t size = tx_size;
+
+	if (tx_data == NULL)
+		return false;
+
+	if (size > MAX_PACKET)
+		size = MAX_PACKET;
+
+	if (!puttx(tx_data, size))
+		return false;
+
+	tx_data = (const char *)tx_data + size;
+	tx_size -= size;
+
+	if (tx_size == 0 && size < MAX_PACKET)
+		tx_data = NULL;
+
+	return true;
+}
+
+/* quetx: enqueue a transmission */
+static void quetx(const void *data, size_t size)
+{
+	tx_data = data;
+	tx_size = size;
+
+	while (pushtx())
+		;
+}
+
+/* usb_endpt0_disable: Disable endpoint 0 (not valid) */
+void usb_endpt0_disable(void)
+{
+}
+
+/* usb_endpt0_enable: Enable and reset endpoint 0 */
+void usb_endpt0_enable(void)
+{
+	BDT_ENDPT(0, BDT_RX, BDT_EVEN).addr = buf[0];
+	BDT_ENDPT(0, BDT_RX, BDT_EVEN).desc = USB0_BD_INIT(sizeof buf[0], 0);
+
+	BDT_ENDPT(0, BDT_RX, BDT_ODD).addr = buf[1];
+	BDT_ENDPT(0, BDT_RX, BDT_ODD).desc = USB0_BD_INIT(sizeof buf[1], 0);
+
+	BDT_ENDPT(0, BDT_TX, BDT_EVEN).addr = NULL;
+	BDT_ENDPT(0, BDT_TX, BDT_EVEN).desc = 0;
+
+	BDT_ENDPT(0, BDT_TX, BDT_ODD).addr = NULL;
+	BDT_ENDPT(0, BDT_TX, BDT_ODD).desc = 0;
+
+	USB0_ENDPT(0) = BV(ENDPT_EPRXEN) | BV(ENDPT_EPTXEN) | BV(ENDPT_EPHSHK);
+	nextaddr = 0;
+	tx_data = NULL;
+	odd = 0;
+	data01 = 0;
+}
+
+/* trunc: truncate size_t to a limit TODO: MOVE THIS */
+static inline size_t trunc(size_t val, size_t max)
+{
+	if (val > max)
+		return max;
+	return val;
+}
+
+/* tok_setup: process a setup token */
+static void tok_setup(struct tok_setup *setup)
+{
+	switch (setup->reqtyp << 8 | setup->req) {
+	case 0x0005: /* SET ADDRESS */
+		nextaddr = setup->value;
+		puttx(NULL, 0);
+		break;
+	case 0x0009: /* SET CONFIGURATION */
+		puttx(NULL, 0);
+		break;
+	case 0x8006: /* GET DESCRIPTOR */
+		switch (setup->value) {
+		case 0x0100: /* DEVICE */
+			quetx(usb_ds_dev, trunc(usb_ds_dev_len, setup->length));
+			return;
+		case 0x0200: /* CONFIGURATION */
+			quetx(usb_ds_conf, trunc(usb_ds_conf_len, setup->length));
+			return;
+		case 0x0300: /* STRING 0 */
+			quetx(usb_ds_lang, trunc(usb_ds_lang_len, setup->length));
+			return;
+		case 0x0301: /* STRING 1 */
+			quetx(usb_ds_str1, trunc(usb_ds_str1_len, setup->length));
+			return;
+		}
+		/* fall through */
+	default:
+		SET_BIT(USB0_ENDPT(0), ENDPT_EPSTALL);
+		break;
+	}
+}
+
+void usb_endpt0_token(uint8_t state)
+{
+	struct usb0_bd *bd;
+	struct tok_setup setup;
+
+	bd = &BDT_ENDPT(0, GET_BIT(state, STAT_TX), GET_BIT(state, STAT_ODD));
+
+
+	switch (GET_BITS(bd->desc, BD_TOK_PID)) {
+	case BD_TOK_PID_OUT:
+		bd->desc = USB0_BD_INIT(sizeof buf[0], 1);
+		break;
+	case BD_TOK_PID_IN:
+		pushtx();
+		if (nextaddr) {
+			USB0_ADDR = nextaddr;
+			nextaddr = 0;
+		}
+		break;
+	case BD_TOK_PID_SETUP:
+		read_setup(&setup, bd->addr);
+		bd->desc = USB0_BD_INIT(sizeof buf[0], 1);
+
+		BDT_ENDPT(0, BDT_TX, BDT_EVEN).desc = 0;
+		BDT_ENDPT(0, BDT_TX, BDT_ODD).desc = 0;
+		tx_data = NULL;
+
+		data01 = 1;
+
+		tok_setup(&setup);
+
+		break;
+	}
+
+	USB0_CTL = BV(CTL_USBENSOFEN);
+}