| Guennadi Liakhovetski | 54e4026 | 2009-04-15 14:25:33 +0200 | [diff] [blame] | 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 | static struct clk *mxc_ahb_clk; |
| 21 | static struct clk *mxc_usb_clk; |
| 22 | |
| 23 | int fsl_udc_clk_init(struct platform_device *pdev) |
| 24 | { |
| 25 | struct fsl_usb2_platform_data *pdata; |
| 26 | unsigned long freq; |
| 27 | int ret; |
| 28 | |
| 29 | pdata = pdev->dev.platform_data; |
| 30 | |
| 31 | mxc_ahb_clk = clk_get(&pdev->dev, "usb_ahb"); |
| 32 | if (IS_ERR(mxc_ahb_clk)) |
| 33 | return PTR_ERR(mxc_ahb_clk); |
| 34 | |
| 35 | ret = clk_enable(mxc_ahb_clk); |
| 36 | if (ret < 0) { |
| 37 | dev_err(&pdev->dev, "clk_enable(\"usb_ahb\") failed\n"); |
| 38 | goto eenahb; |
| 39 | } |
| 40 | |
| 41 | /* make sure USB_CLK is running at 60 MHz +/- 1000 Hz */ |
| 42 | mxc_usb_clk = clk_get(&pdev->dev, "usb"); |
| 43 | if (IS_ERR(mxc_usb_clk)) { |
| 44 | dev_err(&pdev->dev, "clk_get(\"usb\") failed\n"); |
| 45 | ret = PTR_ERR(mxc_usb_clk); |
| 46 | goto egusb; |
| 47 | } |
| 48 | |
| 49 | freq = clk_get_rate(mxc_usb_clk); |
| 50 | if (pdata->phy_mode != FSL_USB2_PHY_ULPI && |
| 51 | (freq < 59999000 || freq > 60001000)) { |
| 52 | dev_err(&pdev->dev, "USB_CLK=%lu, should be 60MHz\n", freq); |
| 53 | goto eclkrate; |
| 54 | } |
| 55 | |
| 56 | ret = clk_enable(mxc_usb_clk); |
| 57 | if (ret < 0) { |
| 58 | dev_err(&pdev->dev, "clk_enable(\"usb_clk\") failed\n"); |
| 59 | goto eenusb; |
| 60 | } |
| 61 | |
| 62 | return 0; |
| 63 | |
| 64 | eenusb: |
| 65 | eclkrate: |
| 66 | clk_put(mxc_usb_clk); |
| 67 | mxc_usb_clk = NULL; |
| 68 | egusb: |
| 69 | clk_disable(mxc_ahb_clk); |
| 70 | eenahb: |
| 71 | clk_put(mxc_ahb_clk); |
| 72 | return ret; |
| 73 | } |
| 74 | |
| 75 | void fsl_udc_clk_finalize(struct platform_device *pdev) |
| 76 | { |
| 77 | struct fsl_usb2_platform_data *pdata = pdev->dev.platform_data; |
| 78 | |
| 79 | /* ULPI transceivers don't need usbpll */ |
| 80 | if (pdata->phy_mode == FSL_USB2_PHY_ULPI) { |
| 81 | clk_disable(mxc_usb_clk); |
| 82 | clk_put(mxc_usb_clk); |
| 83 | mxc_usb_clk = NULL; |
| 84 | } |
| 85 | } |
| 86 | |
| 87 | void fsl_udc_clk_release(void) |
| 88 | { |
| 89 | if (mxc_usb_clk) { |
| 90 | clk_disable(mxc_usb_clk); |
| 91 | clk_put(mxc_usb_clk); |
| 92 | } |
| 93 | clk_disable(mxc_ahb_clk); |
| 94 | clk_put(mxc_ahb_clk); |
| 95 | } |