74 lines
1.7 KiB
C
74 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2011 Google, Inc.
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*/
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#include <linux/export.h>
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#include <linux/kernel.h>
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#include <linux/usb.h>
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#include <linux/io.h>
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#include <linux/usb/otg.h>
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#include <linux/usb/ulpi.h>
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#define ULPI_VIEW_WAKEUP (1 << 31)
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#define ULPI_VIEW_RUN (1 << 30)
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#define ULPI_VIEW_WRITE (1 << 29)
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#define ULPI_VIEW_READ (0 << 29)
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#define ULPI_VIEW_ADDR(x) (((x) & 0xff) << 16)
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#define ULPI_VIEW_DATA_READ(x) (((x) >> 8) & 0xff)
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#define ULPI_VIEW_DATA_WRITE(x) ((x) & 0xff)
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static int ulpi_viewport_wait(void __iomem *view, u32 mask)
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{
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unsigned long usec = 2000;
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while (usec--) {
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if (!(readl(view) & mask))
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return 0;
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udelay(1);
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}
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return -ETIMEDOUT;
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}
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static int ulpi_viewport_read(struct usb_phy *otg, u32 reg)
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{
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int ret;
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void __iomem *view = otg->io_priv;
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writel(ULPI_VIEW_WAKEUP | ULPI_VIEW_WRITE, view);
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ret = ulpi_viewport_wait(view, ULPI_VIEW_WAKEUP);
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if (ret)
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return ret;
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writel(ULPI_VIEW_RUN | ULPI_VIEW_READ | ULPI_VIEW_ADDR(reg), view);
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ret = ulpi_viewport_wait(view, ULPI_VIEW_RUN);
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if (ret)
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return ret;
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return ULPI_VIEW_DATA_READ(readl(view));
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}
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static int ulpi_viewport_write(struct usb_phy *otg, u32 val, u32 reg)
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{
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int ret;
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void __iomem *view = otg->io_priv;
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writel(ULPI_VIEW_WAKEUP | ULPI_VIEW_WRITE, view);
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ret = ulpi_viewport_wait(view, ULPI_VIEW_WAKEUP);
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if (ret)
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return ret;
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writel(ULPI_VIEW_RUN | ULPI_VIEW_WRITE | ULPI_VIEW_DATA_WRITE(val) |
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ULPI_VIEW_ADDR(reg), view);
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return ulpi_viewport_wait(view, ULPI_VIEW_RUN);
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}
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struct usb_phy_io_ops ulpi_viewport_access_ops = {
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.read = ulpi_viewport_read,
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.write = ulpi_viewport_write,
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};
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EXPORT_SYMBOL_GPL(ulpi_viewport_access_ops);
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