usb: otg: Add ulpi viewport access ops
Benoit Goby [Thu, 10 Mar 2011 00:28:54 +0000 (16:28 -0800)]
Add generic access ops for controllers with a ulpi viewport register
(e.g. Chipidea/ARC based controllers).

Signed-off-by: Benoit Goby <benoit@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/otg/Kconfig
drivers/usb/otg/Makefile
drivers/usb/otg/ulpi_viewport.c [new file with mode: 0644]
include/linux/usb/ulpi.h

index ceb24fe..daf3e5f 100644 (file)
@@ -49,6 +49,13 @@ config USB_ULPI
          Enable this to support ULPI connected USB OTG transceivers which
          are likely found on embedded boards.
 
+config USB_ULPI_VIEWPORT
+       bool
+       depends on USB_ULPI
+       help
+         Provides read/write operations to the ULPI phy register set for
+         controllers with a viewport register (e.g. Chipidea/ARC controllers).
+
 config TWL4030_USB
        tristate "TWL4030 USB Transceiver Driver"
        depends on TWL4030_CORE && REGULATOR_TWL4030
index e516894..e22d917 100644 (file)
@@ -16,5 +16,6 @@ obj-$(CONFIG_TWL6030_USB)     += twl6030-usb.o
 obj-$(CONFIG_USB_LANGWELL_OTG) += langwell_otg.o
 obj-$(CONFIG_NOP_USB_XCEIV)    += nop-usb-xceiv.o
 obj-$(CONFIG_USB_ULPI)         += ulpi.o
+obj-$(CONFIG_USB_ULPI_VIEWPORT)        += ulpi_viewport.o
 obj-$(CONFIG_USB_MSM_OTG)      += msm_otg.o
 obj-$(CONFIG_AB8500_USB)       += ab8500-usb.o
diff --git a/drivers/usb/otg/ulpi_viewport.c b/drivers/usb/otg/ulpi_viewport.c
new file mode 100644 (file)
index 0000000..e9a37f9
--- /dev/null
@@ -0,0 +1,80 @@
+/*
+ * 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/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 otg_transceiver *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 otg_transceiver *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 otg_io_access_ops ulpi_viewport_access_ops = {
+       .read   = ulpi_viewport_read,
+       .write  = ulpi_viewport_write,
+};
index 82b1507..9595796 100644 (file)
 struct otg_transceiver *otg_ulpi_create(struct otg_io_access_ops *ops,
                                        unsigned int flags);
 
+#ifdef CONFIG_USB_ULPI_VIEWPORT
+/* access ops for controllers with a viewport register */
+extern struct otg_io_access_ops ulpi_viewport_access_ops;
+#endif
+
 #endif /* __LINUX_USB_ULPI_H */