1 files changed, 73 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-ulpi-viewport.c b/drivers/usb/phy/phy-ulpi-viewport.c
new file mode 100644
index 000000000..7a14e0e3b
--- /dev/null
+++ b/drivers/usb/phy/phy-ulpi-viewport.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/usb.h>
+#include <linux/io.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/ulpi.h>
+
+#define ULPI_VIEW_WAKEUP	(1 << 31)
+#define ULPI_VIEW_RUN		(1 << 30)
+#define ULPI_VIEW_WRITE		(1 << 29)
+#define ULPI_VIEW_READ		(0 << 29)
+#define ULPI_VIEW_ADDR(x)	(((x) & 0xff) << 16)
+#define ULPI_VIEW_DATA_READ(x)	(((x) >> 8) & 0xff)
+#define ULPI_VIEW_DATA_WRITE(x)	((x) & 0xff)
+
+static int ulpi_viewport_wait(void __iomem *view, u32 mask)
+{
+	unsigned long usec = 2000;
+
+	while (usec--) {
+		if (!(readl(view) & mask))
+			return 0;
+
+		udelay(1);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int ulpi_viewport_read(struct usb_phy *otg, u32 reg)
+{
+	int ret;
+	void __iomem *view = otg->io_priv;
+
+	writel(ULPI_VIEW_WAKEUP | ULPI_VIEW_WRITE, view);
+	ret = ulpi_viewport_wait(view, ULPI_VIEW_WAKEUP);
+	if (ret)
+		return ret;
+
+	writel(ULPI_VIEW_RUN | ULPI_VIEW_READ | ULPI_VIEW_ADDR(reg), view);
+	ret = ulpi_viewport_wait(view, ULPI_VIEW_RUN);
+	if (ret)
+		return ret;
+
+	return ULPI_VIEW_DATA_READ(readl(view));
+}
+
+static int ulpi_viewport_write(struct usb_phy *otg, u32 val, u32 reg)
+{
+	int ret;
+	void __iomem *view = otg->io_priv;
+
+	writel(ULPI_VIEW_WAKEUP | ULPI_VIEW_WRITE, view);
+	ret = ulpi_viewport_wait(view, ULPI_VIEW_WAKEUP);
+	if (ret)
+		return ret;
+
+	writel(ULPI_VIEW_RUN | ULPI_VIEW_WRITE | ULPI_VIEW_DATA_WRITE(val) |
+						 ULPI_VIEW_ADDR(reg), view);
+
+	return ulpi_viewport_wait(view, ULPI_VIEW_RUN);
+}
+
+struct usb_phy_io_ops ulpi_viewport_access_ops = {
+	.read	= ulpi_viewport_read,
+	.write	= ulpi_viewport_write,
+};
+EXPORT_SYMBOL_GPL(ulpi_viewport_access_ops);