usb: renesas_usbhs: modify data transfer method

On current driver, main data transfer function was implemented in fifo.c,
but the overall controlling was implementing in mod_gadget.c.
This style is not useful to support host and DMAEngine in the future.

But the interrupt for data transfer cannot separate easily for now,
because it is deeply related to mod_gadget.

This patch move the overall data transfer method
into fifo.c except interrupt.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/renesas_usbhs/fifo.c b/drivers/usb/renesas_usbhs/fifo.c
index 088bfd7..b5031e3 100644
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -27,20 +27,17 @@
 	INIT_LIST_HEAD(&pkt->node);
 }
 
-void usbhs_pkt_update(struct usbhs_pkt *pkt, void *buf, int len)
-{
-	pkt->buf	= buf;
-	pkt->length	= len;
-	pkt->actual	= 0;
-	pkt->maxp	= 0;
-}
-
-void usbhs_pkt_push(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt)
+void usbhs_pkt_push(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt,
+		    void *buf, int len, int zero)
 {
 	list_del_init(&pkt->node);
 	list_add_tail(&pkt->node, &pipe->list);
 
-	pkt->pipe = pipe;
+	pkt->pipe	= pipe;
+	pkt->buf	= buf;
+	pkt->length	= len;
+	pkt->zero	= zero;
+	pkt->actual	= 0;
 }
 
 void usbhs_pkt_pop(struct usbhs_pkt *pkt)
@@ -57,6 +54,47 @@
 }
 
 /*
+ *		irq enable/disable function
+ */
+#define usbhsf_irq_empty_ctrl(p, e) usbhsf_irq_callback_ctrl(p, bempsts, e)
+#define usbhsf_irq_ready_ctrl(p, e) usbhsf_irq_callback_ctrl(p, brdysts, e)
+#define usbhsf_irq_callback_ctrl(pipe, status, enable)			\
+	({								\
+		struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);	\
+		struct usbhs_mod *mod = usbhs_mod_get_current(priv);	\
+		u16 status = (1 << usbhs_pipe_number(pipe));		\
+		if (!mod)						\
+			return;						\
+		if (enable)						\
+			mod->irq_##status |= status;			\
+		else							\
+			mod->irq_##status &= ~status;			\
+		usbhs_irq_callback_update(priv, mod);			\
+	})
+
+static void usbhsf_tx_irq_ctrl(struct usbhs_pipe *pipe, int enable)
+{
+	/*
+	 * And DCP pipe can NOT use "ready interrupt" for "send"
+	 * it should use "empty" interrupt.
+	 * see
+	 *   "Operation" - "Interrupt Function" - "BRDY Interrupt"
+	 *
+	 * on the other hand, normal pipe can use "ready interrupt" for "send"
+	 * even though it is single/double buffer
+	 */
+	if (usbhs_pipe_is_dcp(pipe))
+		usbhsf_irq_empty_ctrl(pipe, enable);
+	else
+		usbhsf_irq_ready_ctrl(pipe, enable);
+}
+
+static void usbhsf_rx_irq_ctrl(struct usbhs_pipe *pipe, int enable)
+{
+	usbhsf_irq_ready_ctrl(pipe, enable);
+}
+
+/*
  *		FIFO ctrl
  */
 static void usbhsf_send_terminator(struct usbhs_pipe *pipe)
@@ -135,34 +173,38 @@
 	struct usbhs_pipe *pipe = pkt->pipe;
 	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
 	struct usbhs_pipe_info *info = usbhs_priv_to_pipeinfo(priv);
+	struct device *dev = usbhs_priv_to_dev(priv);
 	void __iomem *addr = priv->base + CFIFO;
+	u8 *buf;
 	int maxp = usbhs_pipe_get_maxpacket(pipe);
 	int total_len;
-	u8 *buf = pkt->buf;
 	int i, ret, len;
+	int is_short, is_done;
 
 	ret = usbhs_pipe_is_accessible(pipe);
 	if (ret < 0)
-		return ret;
+		goto usbhs_fifo_write_busy;
 
 	ret = usbhsf_fifo_select(pipe, 1);
 	if (ret < 0)
-		return ret;
+		goto usbhs_fifo_write_busy;
 
 	ret = usbhsf_fifo_barrier(priv);
 	if (ret < 0)
-		return ret;
+		goto usbhs_fifo_write_busy;
 
-	len = min(pkt->length, maxp);
-	total_len = len;
+	buf		= pkt->buf    + pkt->actual;
+	len		= pkt->length - pkt->actual;
+	len		= min(len, maxp);
+	total_len	= len;
+	is_short	= total_len < maxp;
 
 	/*
 	 * FIXME
 	 *
 	 * 32-bit access only
 	 */
-	if (len >= 4 &&
-	    !((unsigned long)buf & 0x03)) {
+	if (len >= 4 && !((unsigned long)buf & 0x03)) {
 		iowrite32_rep(addr, buf, len / 4);
 		len %= 4;
 		buf += total_len - len;
@@ -172,19 +214,52 @@
 	for (i = 0; i < len; i++)
 		iowrite8(buf[i], addr + (0x03 - (i & 0x03)));
 
-	if (total_len < maxp)
+	/*
+	 * variable update
+	 */
+	pkt->actual += total_len;
+
+	if (pkt->actual < pkt->length)
+		is_done = 0;		/* there are remainder data */
+	else if (is_short)
+		is_done = 1;		/* short packet */
+	else
+		is_done = !pkt->zero;	/* send zero packet ? */
+
+	/*
+	 * pipe/irq handling
+	 */
+	if (is_short)
 		usbhsf_send_terminator(pipe);
 
+	usbhsf_tx_irq_ctrl(pipe, !is_done);
 	usbhs_pipe_enable(pipe);
 
-	/* update pkt */
-	if (info->tx_done) {
-		pkt->actual	= total_len;
-		pkt->maxp	= maxp;
-		info->tx_done(pkt);
+	dev_dbg(dev, "  send %d (%d/ %d/ %d/ %d)\n",
+		usbhs_pipe_number(pipe),
+		pkt->length, pkt->actual, is_done, pkt->zero);
+
+	/*
+	 * Transmission end
+	 */
+	if (is_done) {
+		if (usbhs_pipe_is_dcp(pipe))
+			usbhs_dcp_control_transfer_done(pipe);
+
+		if (info->tx_done)
+			info->tx_done(pkt);
 	}
 
 	return 0;
+
+usbhs_fifo_write_busy:
+	/*
+	 * pipe is busy.
+	 * retry in interrupt
+	 */
+	usbhsf_tx_irq_ctrl(pipe, 1);
+
+	return ret;
 }
 
 int usbhs_fifo_prepare_read(struct usbhs_pipe *pipe)
@@ -199,6 +274,7 @@
 		return ret;
 
 	usbhs_pipe_enable(pipe);
+	usbhsf_rx_irq_ctrl(pipe, 1);
 
 	return ret;
 }
@@ -207,13 +283,15 @@
 {
 	struct usbhs_pipe *pipe = pkt->pipe;
 	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
-	struct usbhs_pipe_info *info = usbhs_priv_to_pipeinfo(priv);
+	struct device *dev = usbhs_priv_to_dev(priv);
 	void __iomem *addr = priv->base + CFIFO;
-	u8 *buf = pkt->buf;
+	u8 *buf;
+	u32 data = 0;
+	int maxp = usbhs_pipe_get_maxpacket(pipe);
 	int rcv_len, len;
 	int i, ret;
 	int total_len = 0;
-	u32 data = 0;
+	int is_done = 0;
 
 	ret = usbhsf_fifo_select(pipe, 0);
 	if (ret < 0)
@@ -225,6 +303,11 @@
 
 	rcv_len = usbhsf_fifo_rcv_len(priv);
 
+	buf		= pkt->buf    + pkt->actual;
+	len		= pkt->length - pkt->actual;
+	len		= min(len, rcv_len);
+	total_len	= len;
+
 	/*
 	 * Buffer clear if Zero-Length packet
 	 *
@@ -236,19 +319,15 @@
 		goto usbhs_fifo_read_end;
 	}
 
-	len = min(rcv_len, pkt->length);
-	total_len = len;
-
 	/*
 	 * FIXME
 	 *
 	 * 32-bit access only
 	 */
-	if (len >= 4 &&
-	    !((unsigned long)buf & 0x03)) {
+	if (len >= 4 && !((unsigned long)buf & 0x03)) {
 		ioread32_rep(addr, buf, len / 4);
 		len %= 4;
-		buf += rcv_len - len;
+		buf += total_len - len;
 	}
 
 	/* the rest operation */
@@ -259,12 +338,25 @@
 		buf[i] = (data >> ((i & 0x03) * 8)) & 0xff;
 	}
 
+	pkt->actual += total_len;
+
 usbhs_fifo_read_end:
-	if (info->rx_done) {
-		/* update pkt */
-		pkt->actual	= total_len;
-		pkt->maxp	= usbhs_pipe_get_maxpacket(pipe);
-		info->rx_done(pkt);
+	if ((pkt->actual == pkt->length) ||	/* receive all data */
+	    (total_len < maxp))			/* short packet */
+		is_done = 1;
+
+	dev_dbg(dev, "  recv %d (%d/ %d/ %d/ %d)\n",
+		usbhs_pipe_number(pipe),
+		pkt->length, pkt->actual, is_done, pkt->zero);
+
+	if (is_done) {
+		struct usbhs_pipe_info *info = usbhs_priv_to_pipeinfo(priv);
+
+		usbhsf_rx_irq_ctrl(pipe, 0);
+		usbhs_pipe_disable(pipe);
+
+		if (info->rx_done)
+			info->rx_done(pkt);
 	}
 
 	return 0;