1 /* 2 * Arasan Secure Digital Host Controller Interface. 3 * Copyright (C) 2011 - 2012 Michal Simek <monstr@monstr.eu> 4 * Copyright (c) 2012 Wind River Systems, Inc. 5 * Copyright (C) 2013 Pengutronix e.K. 6 * Copyright (C) 2013 Xilinx Inc. 7 * 8 * Based on sdhci-of-esdhc.c 9 * 10 * Copyright (c) 2007 Freescale Semiconductor, Inc. 11 * Copyright (c) 2009 MontaVista Software, Inc. 12 * 13 * Authors: Xiaobo Xie <X.Xie@freescale.com> 14 * Anton Vorontsov <avorontsov@ru.mvista.com> 15 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License as published by 18 * the Free Software Foundation; either version 2 of the License, or (at 19 * your option) any later version. 20 */ 21 22 #include <linux/module.h> 23 #include "sdhci-pltfm.h" 24 25 #define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c 26 27 #define CLK_CTRL_TIMEOUT_SHIFT 16 28 #define CLK_CTRL_TIMEOUT_MASK (0xf << CLK_CTRL_TIMEOUT_SHIFT) 29 #define CLK_CTRL_TIMEOUT_MIN_EXP 13 30 31 /** 32 * struct sdhci_arasan_data 33 * @clk_ahb: Pointer to the AHB clock 34 */ 35 struct sdhci_arasan_data { 36 struct clk *clk_ahb; 37 }; 38 39 static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host) 40 { 41 u32 div; 42 unsigned long freq; 43 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); 44 45 div = readl(host->ioaddr + SDHCI_ARASAN_CLK_CTRL_OFFSET); 46 div = (div & CLK_CTRL_TIMEOUT_MASK) >> CLK_CTRL_TIMEOUT_SHIFT; 47 48 freq = clk_get_rate(pltfm_host->clk); 49 freq /= 1 << (CLK_CTRL_TIMEOUT_MIN_EXP + div); 50 51 return freq; 52 } 53 54 static struct sdhci_ops sdhci_arasan_ops = { 55 .get_max_clock = sdhci_pltfm_clk_get_max_clock, 56 .get_timeout_clock = sdhci_arasan_get_timeout_clock, 57 }; 58 59 static struct sdhci_pltfm_data sdhci_arasan_pdata = { 60 .ops = &sdhci_arasan_ops, 61 }; 62 63 #ifdef CONFIG_PM_SLEEP 64 /** 65 * sdhci_arasan_suspend - Suspend method for the driver 66 * @dev: Address of the device structure 67 * Returns 0 on success and error value on error 68 * 69 * Put the device in a low power state. 70 */ 71 static int sdhci_arasan_suspend(struct device *dev) 72 { 73 struct platform_device *pdev = to_platform_device(dev); 74 struct sdhci_host *host = platform_get_drvdata(pdev); 75 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); 76 struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv; 77 int ret; 78 79 ret = sdhci_suspend_host(host); 80 if (ret) 81 return ret; 82 83 clk_disable(pltfm_host->clk); 84 clk_disable(sdhci_arasan->clk_ahb); 85 86 return 0; 87 } 88 89 /** 90 * sdhci_arasan_resume - Resume method for the driver 91 * @dev: Address of the device structure 92 * Returns 0 on success and error value on error 93 * 94 * Resume operation after suspend 95 */ 96 static int sdhci_arasan_resume(struct device *dev) 97 { 98 struct platform_device *pdev = to_platform_device(dev); 99 struct sdhci_host *host = platform_get_drvdata(pdev); 100 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); 101 struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv; 102 int ret; 103 104 ret = clk_enable(sdhci_arasan->clk_ahb); 105 if (ret) { 106 dev_err(dev, "Cannot enable AHB clock.\n"); 107 return ret; 108 } 109 110 ret = clk_enable(pltfm_host->clk); 111 if (ret) { 112 dev_err(dev, "Cannot enable SD clock.\n"); 113 clk_disable(sdhci_arasan->clk_ahb); 114 return ret; 115 } 116 117 return sdhci_resume_host(host); 118 } 119 #endif /* ! CONFIG_PM_SLEEP */ 120 121 static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend, 122 sdhci_arasan_resume); 123 124 static int sdhci_arasan_probe(struct platform_device *pdev) 125 { 126 int ret; 127 struct clk *clk_xin; 128 struct sdhci_host *host; 129 struct sdhci_pltfm_host *pltfm_host; 130 struct sdhci_arasan_data *sdhci_arasan; 131 132 sdhci_arasan = devm_kzalloc(&pdev->dev, sizeof(*sdhci_arasan), 133 GFP_KERNEL); 134 if (!sdhci_arasan) 135 return -ENOMEM; 136 137 sdhci_arasan->clk_ahb = devm_clk_get(&pdev->dev, "clk_ahb"); 138 if (IS_ERR(sdhci_arasan->clk_ahb)) { 139 dev_err(&pdev->dev, "clk_ahb clock not found.\n"); 140 return PTR_ERR(sdhci_arasan->clk_ahb); 141 } 142 143 clk_xin = devm_clk_get(&pdev->dev, "clk_xin"); 144 if (IS_ERR(clk_xin)) { 145 dev_err(&pdev->dev, "clk_xin clock not found.\n"); 146 return PTR_ERR(clk_xin); 147 } 148 149 ret = clk_prepare_enable(sdhci_arasan->clk_ahb); 150 if (ret) { 151 dev_err(&pdev->dev, "Unable to enable AHB clock.\n"); 152 return ret; 153 } 154 155 ret = clk_prepare_enable(clk_xin); 156 if (ret) { 157 dev_err(&pdev->dev, "Unable to enable SD clock.\n"); 158 goto clk_dis_ahb; 159 } 160 161 host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata, 0); 162 if (IS_ERR(host)) { 163 ret = PTR_ERR(host); 164 dev_err(&pdev->dev, "platform init failed (%u)\n", ret); 165 goto clk_disable_all; 166 } 167 168 sdhci_get_of_property(pdev); 169 pltfm_host = sdhci_priv(host); 170 pltfm_host->priv = sdhci_arasan; 171 pltfm_host->clk = clk_xin; 172 173 ret = sdhci_add_host(host); 174 if (ret) { 175 dev_err(&pdev->dev, "platform register failed (%u)\n", ret); 176 goto err_pltfm_free; 177 } 178 179 return 0; 180 181 err_pltfm_free: 182 sdhci_pltfm_free(pdev); 183 clk_disable_all: 184 clk_disable_unprepare(clk_xin); 185 clk_dis_ahb: 186 clk_disable_unprepare(sdhci_arasan->clk_ahb); 187 188 return ret; 189 } 190 191 static int sdhci_arasan_remove(struct platform_device *pdev) 192 { 193 struct sdhci_host *host = platform_get_drvdata(pdev); 194 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); 195 struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv; 196 197 clk_disable_unprepare(pltfm_host->clk); 198 clk_disable_unprepare(sdhci_arasan->clk_ahb); 199 200 return sdhci_pltfm_unregister(pdev); 201 } 202 203 static const struct of_device_id sdhci_arasan_of_match[] = { 204 { .compatible = "arasan,sdhci-8.9a" }, 205 { } 206 }; 207 MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match); 208 209 static struct platform_driver sdhci_arasan_driver = { 210 .driver = { 211 .name = "sdhci-arasan", 212 .owner = THIS_MODULE, 213 .of_match_table = sdhci_arasan_of_match, 214 .pm = &sdhci_arasan_dev_pm_ops, 215 }, 216 .probe = sdhci_arasan_probe, 217 .remove = sdhci_arasan_remove, 218 }; 219 220 module_platform_driver(sdhci_arasan_driver); 221 222 MODULE_DESCRIPTION("Driver for the Arasan SDHCI Controller"); 223 MODULE_AUTHOR("Soeren Brinkmann <soren.brinkmann@xilinx.com>"); 224 MODULE_LICENSE("GPL"); 225