[PATCH] Revert "usb: dwc2: gadget: fix TX FIFO size and address initialization"

[Leo Yan]

This reverts commit aa381a7259c3f53727bcaa8c5f9359e940a0e3fd.

Reverting this patch, as it incorrectly assumes TX FIFO size is fixed
and cannot change FIFO size; it removes all related dt binding code
and have no chance to set FIFO size at init phase.

As result, Hi6220 cannot set correct FIFO size for gadget driver and
ethernet on USB function driver is easily to hang. And in the kernel
there also have other platforms set FIFO size for usb controller,
e.g. arch/arm64/boot/dts/rockchip/rk3368.dtsi.

This patch re-enables dt binding to set FIFO size.

Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>
---
 drivers/usb/dwc2/core.h   |  7 +++++++
 drivers/usb/dwc2/gadget.c | 53 +++++++++++++++++++++++++++++++++++++----------
 2 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index aad4107..2a21a04 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -259,6 +259,13 @@ enum dwc2_lx_state {
 	DWC2_L3,	/* Off state */
 };
 
+/*
+ * Gadget periodic tx fifo sizes as used by legacy driver
+ * EP0 is not included
+ */
+#define DWC2_G_P_LEGACY_TX_FIFO_SIZE {256, 256, 256, 256, 768, 768, 768, \
+					   768, 0, 0, 0, 0, 0, 0, 0}
+
 /* Gadget ep0 states */
 enum dwc2_ep0_state {
 	DWC2_EP0_SETUP,
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 4cd6403..24fbebc 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -186,10 +186,9 @@ static void dwc2_hsotg_ctrl_epint(struct dwc2_hsotg *hsotg,
  */
 static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 {
-	unsigned int fifo;
+	unsigned int ep;
 	unsigned int addr;
 	int timeout;
-	u32 dptxfsizn;
 	u32 val;
 
 	/* Reset fifo map if not correctly cleared during previous session */
@@ -217,16 +216,16 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	 * them to endpoints dynamically according to maxpacket size value of
 	 * given endpoint.
 	 */
-	for (fifo = 1; fifo < MAX_EPS_CHANNELS; fifo++) {
-		dptxfsizn = dwc2_readl(hsotg->regs + DPTXFSIZN(fifo));
-
-		val = (dptxfsizn & FIFOSIZE_DEPTH_MASK) | addr;
-		addr += dptxfsizn >> FIFOSIZE_DEPTH_SHIFT;
-
-		if (addr > hsotg->fifo_mem)
-			break;
+	for (ep = 1; ep < MAX_EPS_CHANNELS; ep++) {
+		if (!hsotg->g_tx_fifo_sz[ep])
+			continue;
+		val = addr;
+		val |= hsotg->g_tx_fifo_sz[ep] << FIFOSIZE_DEPTH_SHIFT;
+		WARN_ONCE(addr + hsotg->g_tx_fifo_sz[ep] > hsotg->fifo_mem,
+			  "insufficient fifo memory");
+		addr += hsotg->g_tx_fifo_sz[ep];
 
-		dwc2_writel(val, hsotg->regs + DPTXFSIZN(fifo));
+		dwc2_writel(val, hsotg->regs + DPTXFSIZN(ep));
 	}
 
 	/*
@@ -3807,10 +3806,36 @@ static void dwc2_hsotg_dump(struct dwc2_hsotg *hsotg)
 static void dwc2_hsotg_of_probe(struct dwc2_hsotg *hsotg)
 {
 	struct device_node *np = hsotg->dev->of_node;
+	u32 len = 0;
+	u32 i = 0;
 
 	/* Enable dma if requested in device tree */
 	hsotg->g_using_dma = of_property_read_bool(np, "g-use-dma");
 
+	/*
+	* Register TX periodic fifo size per endpoint.
+	* EP0 is excluded since it has no fifo configuration.
+	*/
+	if (!of_find_property(np, "g-tx-fifo-size", &len))
+		goto rx_fifo;
+
+	len /= sizeof(u32);
+
+	/* Read tx fifo sizes other than ep0 */
+	if (of_property_read_u32_array(np, "g-tx-fifo-size",
+						&hsotg->g_tx_fifo_sz[1], len))
+		goto rx_fifo;
+
+	/* Add ep0 */
+	len++;
+
+	/* Make remaining TX fifos unavailable */
+	if (len < MAX_EPS_CHANNELS) {
+		for (i = len; i < MAX_EPS_CHANNELS; i++)
+			hsotg->g_tx_fifo_sz[i] = 0;
+	}
+
+rx_fifo:
 	/* Register RX fifo size */
 	of_property_read_u32(np, "g-rx-fifo-size", &hsotg->g_rx_fifo_sz);
 
@@ -3832,10 +3857,13 @@ int dwc2_gadget_init(struct dwc2_hsotg *hsotg, int irq)
 	struct device *dev = hsotg->dev;
 	int epnum;
 	int ret;
+	int i;
+	u32 p_tx_fifo[] = DWC2_G_P_LEGACY_TX_FIFO_SIZE;
 
 	/* Initialize to legacy fifo configuration values */
 	hsotg->g_rx_fifo_sz = 2048;
 	hsotg->g_np_g_tx_fifo_sz = 1024;
+	memcpy(&hsotg->g_tx_fifo_sz[1], p_tx_fifo, sizeof(p_tx_fifo));
 	/* Device tree specific probe */
 	dwc2_hsotg_of_probe(hsotg);
 
@@ -3853,6 +3881,9 @@ int dwc2_gadget_init(struct dwc2_hsotg *hsotg, int irq)
 	dev_dbg(dev, "NonPeriodic TXFIFO size: %d\n",
 						hsotg->g_np_g_tx_fifo_sz);
 	dev_dbg(dev, "RXFIFO size: %d\n", hsotg->g_rx_fifo_sz);
+	for (i = 0; i < MAX_EPS_CHANNELS; i++)
+		dev_dbg(dev, "Periodic TXFIFO%2d size: %d\n", i,
+						hsotg->g_tx_fifo_sz[i]);
 
 	hsotg->gadget.max_speed = USB_SPEED_HIGH;
 	hsotg->gadget.ops = &dwc2_hsotg_gadget_ops;
-- 
1.9.1