fsl_mx3_udc.c
/*
* 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);
}