diff options
Diffstat (limited to 'drivers/usb/phy/phy-ulpi-viewport.c')
-rw-r--r-- | drivers/usb/phy/phy-ulpi-viewport.c | 82 |
1 files changed, 82 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..18bb8264b --- /dev/null +++ b/drivers/usb/phy/phy-ulpi-viewport.c @@ -0,0 +1,82 @@ +/* + * Copyright (C) 2011 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#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); |