USB: gadget: Add i.MX3x support to the fsl_usb2_udc driver

This patch adds support for i.MX3x (only tested with i.MX31 so far) ARM
SoCs to the fsl_usb2_udc driver. It also moves PHY configuration before
controller reset, because otherwise an ULPI PHY doesn't get a reset and
doesn't function after a reboot. The problem with longer control transfers
is still not fixed. The patch renames the fsl_usb2_udc.c file to
fsl_udc_core.c to preserve the same module name for user-space
backwards compatibility.

Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/fsl_mx3_udc.c b/drivers/usb/gadget/fsl_mx3_udc.c
new file mode 100644
index 0000000..4bc2bf3
--- /dev/null
+++ b/drivers/usb/gadget/fsl_mx3_udc.c
@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2009
+ * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
+ *
+ * Description:
+ * Helper routines for i.MX3x SoCs from Freescale, needed by the fsl_usb2_udc.c
+ * driver to function correctly on these systems.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/fsl_devices.h>
+#include <linux/platform_device.h>
+
+static struct clk *mxc_ahb_clk;
+static struct clk *mxc_usb_clk;
+
+int fsl_udc_clk_init(struct platform_device *pdev)
+{
+	struct fsl_usb2_platform_data *pdata;
+	unsigned long freq;
+	int ret;
+
+	pdata = pdev->dev.platform_data;
+
+	mxc_ahb_clk = clk_get(&pdev->dev, "usb_ahb");
+	if (IS_ERR(mxc_ahb_clk))
+		return PTR_ERR(mxc_ahb_clk);
+
+	ret = clk_enable(mxc_ahb_clk);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "clk_enable(\"usb_ahb\") failed\n");
+		goto eenahb;
+	}
+
+	/* make sure USB_CLK is running at 60 MHz +/- 1000 Hz */
+	mxc_usb_clk = clk_get(&pdev->dev, "usb");
+	if (IS_ERR(mxc_usb_clk)) {
+		dev_err(&pdev->dev, "clk_get(\"usb\") failed\n");
+		ret = PTR_ERR(mxc_usb_clk);
+		goto egusb;
+	}
+
+	freq = clk_get_rate(mxc_usb_clk);
+	if (pdata->phy_mode != FSL_USB2_PHY_ULPI &&
+	    (freq < 59999000 || freq > 60001000)) {
+		dev_err(&pdev->dev, "USB_CLK=%lu, should be 60MHz\n", freq);
+		goto eclkrate;
+	}
+
+	ret = clk_enable(mxc_usb_clk);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "clk_enable(\"usb_clk\") failed\n");
+		goto eenusb;
+	}
+
+	return 0;
+
+eenusb:
+eclkrate:
+	clk_put(mxc_usb_clk);
+	mxc_usb_clk = NULL;
+egusb:
+	clk_disable(mxc_ahb_clk);
+eenahb:
+	clk_put(mxc_ahb_clk);
+	return ret;
+}
+
+void fsl_udc_clk_finalize(struct platform_device *pdev)
+{
+	struct fsl_usb2_platform_data *pdata = pdev->dev.platform_data;
+
+	/* ULPI transceivers don't need usbpll */
+	if (pdata->phy_mode == FSL_USB2_PHY_ULPI) {
+		clk_disable(mxc_usb_clk);
+		clk_put(mxc_usb_clk);
+		mxc_usb_clk = NULL;
+	}
+}
+
+void fsl_udc_clk_release(void)
+{
+	if (mxc_usb_clk) {
+		clk_disable(mxc_usb_clk);
+		clk_put(mxc_usb_clk);
+	}
+	clk_disable(mxc_ahb_clk);
+	clk_put(mxc_ahb_clk);
+}