usb: dwc2: Update bit polling functionality

Move dwc2_hsotg_wait_bit_set function to core.c so it can be used
anywhere in the code.

Added dwc2_hsotg_wait_bit_clear function in core.c.

Replace all the parts of register bit polling code with
dwc2_hsotg_wait_bit_set or dwc2_hsotg_wait_bit_clear functions
calls depends on code logic.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc2/core.c

@@ -317,7 +317,6 @@ static bool dwc2_iddig_filter_enabled(struct dwc2_hsotg *hsotg)
 int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait)
 {
 	u32 greset;
-	int count = 0;
 	bool wait_for_host_mode = false;
 
 	dev_vdbg(hsotg->dev, "%s()\n", __func__);
@@ -346,29 +345,19 @@ int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait)
 	greset = dwc2_readl(hsotg->regs + GRSTCTL);
 	greset |= GRSTCTL_CSFTRST;
 	dwc2_writel(greset, hsotg->regs + GRSTCTL);
-	do {
-		udelay(1);
-		greset = dwc2_readl(hsotg->regs + GRSTCTL);
-		if (++count > 50) {
-			dev_warn(hsotg->dev,
-				 "%s() HANG! Soft Reset GRSTCTL=%0x\n",
-				 __func__, greset);
-			return -EBUSY;
-		}
-	} while (greset & GRSTCTL_CSFTRST);
+
+	if (dwc2_hsotg_wait_bit_clear(hsotg, GRSTCTL, GRSTCTL_CSFTRST, 50)) {
+		dev_warn(hsotg->dev, "%s: HANG! Soft Reset timeout GRSTCTL GRSTCTL_CSFTRST\n",
+			 __func__);
+		return -EBUSY;
+	}
 
 	/* Wait for AHB master IDLE state */
-	count = 0;
-	do {
-		udelay(1);
-		greset = dwc2_readl(hsotg->regs + GRSTCTL);
-		if (++count > 50) {
-			dev_warn(hsotg->dev,
-				 "%s() HANG! AHB Idle GRSTCTL=%0x\n",
-				 __func__, greset);
-			return -EBUSY;
-		}
-	} while (!(greset & GRSTCTL_AHBIDLE));
+	if (dwc2_hsotg_wait_bit_set(hsotg, GRSTCTL, GRSTCTL_AHBIDLE, 50)) {
+		dev_warn(hsotg->dev, "%s: HANG! AHB Idle timeout GRSTCTL GRSTCTL_AHBIDLE\n",
+			 __func__);
+		return -EBUSY;
+	}
 
 	if (wait_for_host_mode && !skip_wait)
 		dwc2_wait_for_mode(hsotg, true);
@@ -683,7 +672,6 @@ void dwc2_dump_global_registers(struct dwc2_hsotg *hsotg)
 void dwc2_flush_tx_fifo(struct dwc2_hsotg *hsotg, const int num)
 {
 	u32 greset;
-	int count = 0;
 
 	dev_vdbg(hsotg->dev, "Flush Tx FIFO %d\n", num);
 
@@ -691,17 +679,9 @@ void dwc2_flush_tx_fifo(struct dwc2_hsotg *hsotg, const int num)
 	greset |= num << GRSTCTL_TXFNUM_SHIFT & GRSTCTL_TXFNUM_MASK;
 	dwc2_writel(greset, hsotg->regs + GRSTCTL);
 
-	do {
-		greset = dwc2_readl(hsotg->regs + GRSTCTL);
-		if (++count > 10000) {
-			dev_warn(hsotg->dev,
-				 "%s() HANG! GRSTCTL=%0x GNPTXSTS=0x%08x\n",
-				 __func__, greset,
-				 dwc2_readl(hsotg->regs + GNPTXSTS));
-			break;
-		}
-		udelay(1);
-	} while (greset & GRSTCTL_TXFFLSH);
+	if (dwc2_hsotg_wait_bit_clear(hsotg, GRSTCTL, GRSTCTL_TXFFLSH, 10000))
+		dev_warn(hsotg->dev, "%s:  HANG! timeout GRSTCTL GRSTCTL_TXFFLSH\n",
+			 __func__);
 
 	/* Wait for at least 3 PHY Clocks */
 	udelay(1);
@@ -715,22 +695,16 @@ void dwc2_flush_tx_fifo(struct dwc2_hsotg *hsotg, const int num)
 void dwc2_flush_rx_fifo(struct dwc2_hsotg *hsotg)
 {
 	u32 greset;
-	int count = 0;
 
 	dev_vdbg(hsotg->dev, "%s()\n", __func__);
 
 	greset = GRSTCTL_RXFFLSH;
 	dwc2_writel(greset, hsotg->regs + GRSTCTL);
 
-	do {
-		greset = dwc2_readl(hsotg->regs + GRSTCTL);
-		if (++count > 10000) {
-			dev_warn(hsotg->dev, "%s() HANG! GRSTCTL=%0x\n",
-				 __func__, greset);
-			break;
-		}
-		udelay(1);
-	} while (greset & GRSTCTL_RXFFLSH);
+	/* Wait for RxFIFO flush done */
+	if (dwc2_hsotg_wait_bit_clear(hsotg, GRSTCTL, GRSTCTL_RXFFLSH, 10000))
+		dev_warn(hsotg->dev, "%s: HANG! timeout GRSTCTL GRSTCTL_RXFFLSH\n",
+			 __func__);
 
 	/* Wait for at least 3 PHY Clocks */
 	udelay(1);
@@ -825,6 +799,52 @@ bool dwc2_hw_is_device(struct dwc2_hsotg *hsotg)
 		(op_mode == GHWCFG2_OP_MODE_NO_SRP_CAPABLE_DEVICE);
 }
 
+/**
+ * dwc2_hsotg_wait_bit_set - Waits for bit to be set.
+ * @hsotg: Programming view of DWC_otg controller.
+ * @offset: Register's offset where bit/bits must be set.
+ * @mask: Mask of the bit/bits which must be set.
+ * @timeout: Timeout to wait.
+ *
+ * Return: 0 if bit/bits are set or -ETIMEDOUT in case of timeout.
+ */
+int dwc2_hsotg_wait_bit_set(struct dwc2_hsotg *hsotg, u32 offset, u32 mask,
+			    u32 timeout)
+{
+	u32 i;
+
+	for (i = 0; i < timeout; i++) {
+		if (dwc2_readl(hsotg->regs + offset) & mask)
+			return 0;
+		udelay(1);
+	}
+
+	return -ETIMEDOUT;
+}
+
+/**
+ * dwc2_hsotg_wait_bit_clear - Waits for bit to be clear.
+ * @hsotg: Programming view of DWC_otg controller.
+ * @offset: Register's offset where bit/bits must be set.
+ * @mask: Mask of the bit/bits which must be set.
+ * @timeout: Timeout to wait.
+ *
+ * Return: 0 if bit/bits are set or -ETIMEDOUT in case of timeout.
+ */
+int dwc2_hsotg_wait_bit_clear(struct dwc2_hsotg *hsotg, u32 offset, u32 mask,
+			      u32 timeout)
+{
+	u32 i;
+
+	for (i = 0; i < timeout; i++) {
+		if (!(dwc2_readl(hsotg->regs + offset) & mask))
+			return 0;
+		udelay(1);
+	}
+
+	return -ETIMEDOUT;
+}
+
 MODULE_DESCRIPTION("DESIGNWARE HS OTG Core");
 MODULE_AUTHOR("Synopsys, Inc.");
 MODULE_LICENSE("Dual BSD/GPL");

drivers/usb/dwc2/core.h

@@ -1142,6 +1142,11 @@ extern const struct of_device_id dwc2_of_match_table[];
 int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg);
 int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg);
 
+/* Common polling functions */
+int dwc2_hsotg_wait_bit_set(struct dwc2_hsotg *hs_otg, u32 reg, u32 bit,
+			    u32 timeout);
+int dwc2_hsotg_wait_bit_clear(struct dwc2_hsotg *hs_otg, u32 reg, u32 bit,
+			      u32 timeout);
 /* Parameters */
 int dwc2_get_hwparams(struct dwc2_hsotg *hsotg);
 int dwc2_init_params(struct dwc2_hsotg *hsotg);

drivers/usb/dwc2/gadget.c

@@ -252,6 +252,7 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	unsigned int ep;
 	unsigned int addr;
 	int timeout;
+
 	u32 val;
 	u32 *txfsz = hsotg->params.g_tx_fifo_size;
 
@@ -2495,30 +2496,13 @@ bad_mps:
  */
 static void dwc2_hsotg_txfifo_flush(struct dwc2_hsotg *hsotg, unsigned int idx)
 {
-	int timeout;
-	int val;
-
 	dwc2_writel(GRSTCTL_TXFNUM(idx) | GRSTCTL_TXFFLSH,
 		    hsotg->regs + GRSTCTL);
 
 	/* wait until the fifo is flushed */
-	timeout = 100;
-
-	while (1) {
-		val = dwc2_readl(hsotg->regs + GRSTCTL);
-
-		if ((val & (GRSTCTL_TXFFLSH)) == 0)
-			break;
-
-		if (--timeout == 0) {
-			dev_err(hsotg->dev,
-				"%s: timeout flushing fifo (GRSTCTL=%08x)\n",
-				__func__, val);
-			break;
-		}
-
-		udelay(1);
-	}
+	if (dwc2_hsotg_wait_bit_clear(hsotg, GRSTCTL, GRSTCTL_TXFFLSH, 100))
+		dev_warn(hsotg->dev, "%s: timeout flushing fifo GRSTCTL_TXFFLSH\n",
+			 __func__);
 }
 
 /**
@@ -3676,20 +3660,6 @@ irq_retry:
 	return IRQ_HANDLED;
 }
 
-static int dwc2_hsotg_wait_bit_set(struct dwc2_hsotg *hs_otg, u32 reg,
-				   u32 bit, u32 timeout)
-{
-	u32 i;
-
-	for (i = 0; i < timeout; i++) {
-		if (dwc2_readl(hs_otg->regs + reg) & bit)
-			return 0;
-		udelay(1);
-	}
-
-	return -ETIMEDOUT;
-}
-
 static void dwc2_hsotg_ep_stop_xfr(struct dwc2_hsotg *hsotg,
 				   struct dwc2_hsotg_ep *hs_ep)
 {

drivers/usb/dwc2/hcd.c

@@ -2403,24 +2403,18 @@ static void dwc2_core_host_init(struct dwc2_hsotg *hsotg)
 
 		/* Halt all channels to put them into a known state */
 		for (i = 0; i < num_channels; i++) {
-			int count = 0;
-
 			hcchar = dwc2_readl(hsotg->regs + HCCHAR(i));
 			hcchar |= HCCHAR_CHENA | HCCHAR_CHDIS;
 			hcchar &= ~HCCHAR_EPDIR;
 			dwc2_writel(hcchar, hsotg->regs + HCCHAR(i));
 			dev_dbg(hsotg->dev, "%s: Halt channel %d\n",
 				__func__, i);
-			do {
-				hcchar = dwc2_readl(hsotg->regs + HCCHAR(i));
-				if (++count > 1000) {
-					dev_err(hsotg->dev,
-						"Unable to clear enable on channel %d\n",
-						i);
-					break;
-				}
-				udelay(1);
-			} while (hcchar & HCCHAR_CHENA);
+
+			if (dwc2_hsotg_wait_bit_clear(hsotg, HCCHAR(i),
+						      HCCHAR_CHENA, 1000)) {
+				dev_warn(hsotg->dev, "Unable to clear enable on channel %d\n",
+					 i);
+			}
 		}
 	}