xhci-pci: asmedia: {read,write}_reg changes from u-boot review

Change asmedia_read_reg and asmedia_write_reg to return error codes. The
read value for asmedia_read_reg is passed via pointer.

Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Signed-off-by: Janne Grunau <j@jannau.net>

Author: kettenis

drivers/usb/host/xhci-pci-asmedia.c

@@ -190,7 +190,7 @@ static int asmedia_wait_reset(struct pci_dev *pdev)
 	return ret;
 }
 
-static u8 asmedia_read_reg(struct usb_hcd *hcd, u16 addr) {
+static int asmedia_read_reg(struct usb_hcd *hcd, u16 addr, u8 *val) {
 	void __iomem *regs = hcd->regs;
 	u8 status;
 	int ret;
@@ -202,7 +202,7 @@ static u8 asmedia_read_reg(struct usb_hcd *hcd, u16 addr) {
 	if (ret) {
 		dev_err(hcd->self.controller,
 			"Read reg wait timed out ([%04x])\n", addr);
-		return ~0;
+		return ret;
 	}
 
 	writew_relaxed(addr, regs + ASMT_REG_ADDR);
@@ -214,13 +214,14 @@ static u8 asmedia_read_reg(struct usb_hcd *hcd, u16 addr) {
 	if (ret) {
 		dev_err(hcd->self.controller,
 			"Read reg addr timed out ([%04x])\n", addr);
-		return ~0;
+		return ret;
 	}
 
-	return readb_relaxed(regs + ASMT_REG_RDATA);
+	*val = readb_relaxed(regs + ASMT_REG_RDATA);
+	return 0;
 }
 
-static void asmedia_write_reg(struct usb_hcd *hcd, u16 addr, u8 data, bool wait) {
+static int asmedia_write_reg(struct usb_hcd *hcd, u16 addr, u8 data, bool wait) {
 	void __iomem *regs = hcd->regs;
 	u8 status;
 	int ret, i;
@@ -231,35 +232,45 @@ static void asmedia_write_reg(struct usb_hcd *hcd, u16 addr, u8 data, bool wait)
 				 !(status & ASMT_REG_STATUS_BUSY),
 				 1000, TIMEOUT_USEC);
 
-	if (ret)
+	if (ret) {
 		dev_err(hcd->self.controller,
 			"Write reg addr timed out ([%04x] = %02x)\n",
 			addr, data);
+		return ret;
+	}
 
 	writeb_relaxed(data, regs + ASMT_REG_WDATA);
 
 	ret = readb_poll_timeout(regs + ASMT_REG_STATUS, status,
 				 !(status & ASMT_REG_STATUS_BUSY),
 				 1000, TIMEOUT_USEC);
 
-	if (ret)
+	if (ret) {
 		dev_err(hcd->self.controller,
 			"Write reg data timed out ([%04x] = %02x)\n",
 			addr, data);
+		return ret;
+	}
 
 	if (!wait)
-		return;
+		return 0;
 
 	for (i = 0; i < TIMEOUT_USEC; i++) {
-		if (asmedia_read_reg(hcd, addr) == data)
+		ret = asmedia_read_reg(hcd, addr, &status);
+		if (ret)
+			return ret;
+		if (status == data)
 			break;
 	}
 
 	if (i >= TIMEOUT_USEC) {
 		dev_err(hcd->self.controller,
 			"Verify register timed out ([%04x] = %02x)\n",
 			addr, data);
+		return -ETIMEDOUT;
 	}
+
+	return 0;
 }
 
 static int asmedia_load_fw(struct pci_dev *pdev, const struct firmware *fw)
@@ -276,23 +287,31 @@ static int asmedia_load_fw(struct pci_dev *pdev, const struct firmware *fw)
 	hcd = dev_get_drvdata(&pdev->dev);
 	regs = hcd->regs;
 
-	asmedia_write_reg(hcd, ASMT_MMIO_CPU_MODE_NEXT,
-			  ASMT_MMIO_CPU_MODE_HALFSPEED, false);
+	ret = asmedia_write_reg(hcd, ASMT_MMIO_CPU_MODE_NEXT,
+				ASMT_MMIO_CPU_MODE_HALFSPEED, false);
+	if (ret)
+		return ret;
 
-	asmedia_write_reg(hcd, ASMT_MMIO_CPU_EXEC_CTRL,
-			  ASMT_MMIO_CPU_EXEC_CTRL_RESET, false);
+	ret = asmedia_write_reg(hcd, ASMT_MMIO_CPU_EXEC_CTRL,
+				ASMT_MMIO_CPU_EXEC_CTRL_RESET, false);
+	if (ret)
+		return ret;
 
 	ret = asmedia_wait_reset(pdev);
 	if (ret) {
 		dev_err(hcd->self.controller, "Failed pre-upload reset\n");
 		return ret;
 	}
 
-	asmedia_write_reg(hcd, ASMT_MMIO_CPU_EXEC_CTRL,
-			  ASMT_MMIO_CPU_EXEC_CTRL_HALT, false);
+	ret = asmedia_write_reg(hcd, ASMT_MMIO_CPU_EXEC_CTRL,
+				ASMT_MMIO_CPU_EXEC_CTRL_HALT, false);
+	if (ret)
+		return ret;
 
-	asmedia_write_reg(hcd, ASMT_MMIO_CPU_MISC,
-			  ASMT_MMIO_CPU_MISC_CODE_RAM_WR, true);
+	ret = asmedia_write_reg(hcd, ASMT_MMIO_CPU_MISC,
+				ASMT_MMIO_CPU_MISC_CODE_RAM_WR, true);
+	if (ret)
+		return ret;
 
 	pci_write_config_byte(pdev, ASMT_CFG_SRAM_ACCESS,
 			      ASMT_CFG_SRAM_ACCESS_ENABLE);
@@ -328,13 +347,19 @@ static int asmedia_load_fw(struct pci_dev *pdev, const struct firmware *fw)
 
 	pci_write_config_byte(pdev, ASMT_CFG_SRAM_ACCESS, 0);
 
-	asmedia_write_reg(hcd, ASMT_MMIO_CPU_MISC, 0, true);
+	ret = asmedia_write_reg(hcd, ASMT_MMIO_CPU_MISC, 0, true);
+	if (ret)
+		return ret;
 
-	asmedia_write_reg(hcd, ASMT_MMIO_CPU_MODE_NEXT,
-			  ASMT_MMIO_CPU_MODE_RAM |
-			  ASMT_MMIO_CPU_MODE_HALFSPEED, false);
+	ret = asmedia_write_reg(hcd, ASMT_MMIO_CPU_MODE_NEXT,
+				ASMT_MMIO_CPU_MODE_RAM |
+				ASMT_MMIO_CPU_MODE_HALFSPEED, false);
+	if (ret)
+		return ret;
 
-	asmedia_write_reg(hcd, ASMT_MMIO_CPU_EXEC_CTRL, 0, false);
+	ret = asmedia_write_reg(hcd, ASMT_MMIO_CPU_EXEC_CTRL, 0, false);
+	if (ret)
+		return ret;
 
 	ret = asmedia_wait_reset(pdev);
 	if (ret) {