1/* 2 * Copyright (C) 2009 3 * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de> 4 * 5 * Description: 6 * Helper routines for i.MX3x SoCs from Freescale, needed by the fsl_usb2_udc.c 7 * driver to function correctly on these systems. 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2 of the License, or (at your 12 * option) any later version. 13 */ 14#include <linux/clk.h> 15#include <linux/delay.h> 16#include <linux/err.h> 17#include <linux/fsl_devices.h> 18#include <linux/platform_device.h> 19 20#include <mach/hardware.h> 21 22static struct clk *mxc_ahb_clk; 23static struct clk *mxc_usb_clk; 24 25int fsl_udc_clk_init(struct platform_device *pdev) 26{ 27 struct fsl_usb2_platform_data *pdata; 28 unsigned long freq; 29 int ret; 30 31 pdata = pdev->dev.platform_data; 32 33 if (!cpu_is_mx35() && !cpu_is_mx25()) { 34 mxc_ahb_clk = clk_get(&pdev->dev, "usb_ahb"); 35 if (IS_ERR(mxc_ahb_clk)) 36 return PTR_ERR(mxc_ahb_clk); 37 38 ret = clk_enable(mxc_ahb_clk); 39 if (ret < 0) { 40 dev_err(&pdev->dev, "clk_enable(\"usb_ahb\") failed\n"); 41 goto eenahb; 42 } 43 } 44 45 /* make sure USB_CLK is running at 60 MHz +/- 1000 Hz */ 46 mxc_usb_clk = clk_get(&pdev->dev, "usb"); 47 if (IS_ERR(mxc_usb_clk)) { 48 dev_err(&pdev->dev, "clk_get(\"usb\") failed\n"); 49 ret = PTR_ERR(mxc_usb_clk); 50 goto egusb; 51 } 52 53 if (!cpu_is_mx51()) { 54 freq = clk_get_rate(mxc_usb_clk); 55 if (pdata->phy_mode != FSL_USB2_PHY_ULPI && 56 (freq < 59999000 || freq > 60001000)) { 57 dev_err(&pdev->dev, "USB_CLK=%lu, should be 60MHz\n", freq); 58 ret = -EINVAL; 59 goto eclkrate; 60 } 61 } 62 63 ret = clk_enable(mxc_usb_clk); 64 if (ret < 0) { 65 dev_err(&pdev->dev, "clk_enable(\"usb_clk\") failed\n"); 66 goto eenusb; 67 } 68 69 return 0; 70 71eenusb: 72eclkrate: 73 clk_put(mxc_usb_clk); 74 mxc_usb_clk = NULL; 75egusb: 76 if (!cpu_is_mx35()) 77 clk_disable(mxc_ahb_clk); 78eenahb: 79 if (!cpu_is_mx35()) 80 clk_put(mxc_ahb_clk); 81 return ret; 82} 83 84void fsl_udc_clk_finalize(struct platform_device *pdev) 85{ 86 struct fsl_usb2_platform_data *pdata = pdev->dev.platform_data; 87 88 /* ULPI transceivers don't need usbpll */ 89 if (pdata->phy_mode == FSL_USB2_PHY_ULPI) { 90 clk_disable(mxc_usb_clk); 91 clk_put(mxc_usb_clk); 92 mxc_usb_clk = NULL; 93 } 94} 95 96void fsl_udc_clk_release(void) 97{ 98 if (mxc_usb_clk) { 99 clk_disable(mxc_usb_clk); 100 clk_put(mxc_usb_clk); 101 } 102 if (!cpu_is_mx35()) { 103 clk_disable(mxc_ahb_clk); 104 clk_put(mxc_ahb_clk); 105 } 106} 107