drivers/mmc/host/sdhci-of-arasan.c

   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 <linux/of_device.h>
  24 #include "sdhci-pltfm.h"
  25
  26 #define SDHCI_ARASAN_CLK_CTRL_OFFSET    0x2c
  27
  28 #define CLK_CTRL_TIMEOUT_SHIFT          16
  29 #define CLK_CTRL_TIMEOUT_MASK           (0xf << CLK_CTRL_TIMEOUT_SHIFT)
  30 #define CLK_CTRL_TIMEOUT_MIN_EXP        13
  31
  32 /**
  33  * struct sdhci_arasan_data
  34  * @clk_ahb:    Pointer to the AHB clock
  35  */
  36 struct sdhci_arasan_data {
  37         struct clk      *clk_ahb;
  38 };
  39
  40 static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
  41 {
  42         u32 div;
  43         unsigned long freq;
  44         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  45
  46         div = readl(host->ioaddr + SDHCI_ARASAN_CLK_CTRL_OFFSET);
  47         div = (div & CLK_CTRL_TIMEOUT_MASK) >> CLK_CTRL_TIMEOUT_SHIFT;
  48
  49         freq = clk_get_rate(pltfm_host->clk);
  50         freq /= 1 << (CLK_CTRL_TIMEOUT_MIN_EXP + div);
  51
  52         return freq;
  53 }
  54
  55 static struct sdhci_ops sdhci_arasan_ops = {
  56         .set_clock = sdhci_set_clock,
  57         .get_max_clock = sdhci_pltfm_clk_get_max_clock,
  58         .get_timeout_clock = sdhci_arasan_get_timeout_clock,
  59         .set_bus_width = sdhci_set_bus_width,
  60         .reset = sdhci_reset,
  61         .set_uhs_signaling = sdhci_set_uhs_signaling,
  62 };
  63
  64 static struct sdhci_pltfm_data sdhci_arasan_pdata = {
  65         .ops = &sdhci_arasan_ops,
  66         .quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
  67         .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
  68                         SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN,
  69 };
  70
  71 #ifdef CONFIG_PM_SLEEP
  72 /**
  73  * sdhci_arasan_suspend - Suspend method for the driver
  74  * @dev:        Address of the device structure
  75  * Returns 0 on success and error value on error
  76  *
  77  * Put the device in a low power state.
  78  */
  79 static int sdhci_arasan_suspend(struct device *dev)
  80 {
  81         struct platform_device *pdev = to_platform_device(dev);
  82         struct sdhci_host *host = platform_get_drvdata(pdev);
  83         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  84         struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
  85         int ret;
  86
  87         ret = sdhci_suspend_host(host);
  88         if (ret)
  89                 return ret;
  90
  91         clk_disable(pltfm_host->clk);
  92         clk_disable(sdhci_arasan->clk_ahb);
  93
  94         return 0;
  95 }
  96
  97 /**
  98  * sdhci_arasan_resume - Resume method for the driver
  99  * @dev:        Address of the device structure
 100  * Returns 0 on success and error value on error
 101  *
 102  * Resume operation after suspend
 103  */
 104 static int sdhci_arasan_resume(struct device *dev)
 105 {
 106         struct platform_device *pdev = to_platform_device(dev);
 107         struct sdhci_host *host = platform_get_drvdata(pdev);
 108         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 109         struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
 110         int ret;
 111
 112         ret = clk_enable(sdhci_arasan->clk_ahb);
 113         if (ret) {
 114                 dev_err(dev, "Cannot enable AHB clock.\n");
 115                 return ret;
 116         }
 117
 118         ret = clk_enable(pltfm_host->clk);
 119         if (ret) {
 120                 dev_err(dev, "Cannot enable SD clock.\n");
 121                 clk_disable(sdhci_arasan->clk_ahb);
 122                 return ret;
 123         }
 124
 125         return sdhci_resume_host(host);
 126 }
 127 #endif /* ! CONFIG_PM_SLEEP */
 128
 129 static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
 130                          sdhci_arasan_resume);
 131
 132 static int sdhci_arasan_probe(struct platform_device *pdev)
 133 {
 134         int ret;
 135         struct clk *clk_xin;
 136         struct sdhci_host *host;
 137         struct sdhci_pltfm_host *pltfm_host;
 138         struct sdhci_arasan_data *sdhci_arasan;
 139
 140         sdhci_arasan = devm_kzalloc(&pdev->dev, sizeof(*sdhci_arasan),
 141                         GFP_KERNEL);
 142         if (!sdhci_arasan)
 143                 return -ENOMEM;
 144
 145         sdhci_arasan->clk_ahb = devm_clk_get(&pdev->dev, "clk_ahb");
 146         if (IS_ERR(sdhci_arasan->clk_ahb)) {
 147                 dev_err(&pdev->dev, "clk_ahb clock not found.\n");
 148                 return PTR_ERR(sdhci_arasan->clk_ahb);
 149         }
 150
 151         clk_xin = devm_clk_get(&pdev->dev, "clk_xin");
 152         if (IS_ERR(clk_xin)) {
 153                 dev_err(&pdev->dev, "clk_xin clock not found.\n");
 154                 return PTR_ERR(clk_xin);
 155         }
 156
 157         ret = clk_prepare_enable(sdhci_arasan->clk_ahb);
 158         if (ret) {
 159                 dev_err(&pdev->dev, "Unable to enable AHB clock.\n");
 160                 return ret;
 161         }
 162
 163         ret = clk_prepare_enable(clk_xin);
 164         if (ret) {
 165                 dev_err(&pdev->dev, "Unable to enable SD clock.\n");
 166                 goto clk_dis_ahb;
 167         }
 168
 169         host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata, 0);
 170         if (IS_ERR(host)) {
 171                 ret = PTR_ERR(host);
 172                 goto clk_disable_all;
 173         }
 174
 175         if (of_device_is_compatible(pdev->dev.of_node, "arasan,sdhci-4.9a")) {
 176                 host->quirks |= SDHCI_QUIRK_NO_HISPD_BIT;
 177                 host->quirks2 |= SDHCI_QUIRK2_HOST_NO_CMD23;
 178         }
 179
 180         sdhci_get_of_property(pdev);
 181         pltfm_host = sdhci_priv(host);
 182         pltfm_host->priv = sdhci_arasan;
 183         pltfm_host->clk = clk_xin;
 184
 185         ret = mmc_of_parse(host->mmc);
 186         if (ret) {
 187                 dev_err(&pdev->dev, "parsing dt failed (%u)\n", ret);
 188                 goto clk_disable_all;
 189         }
 190
 191         ret = sdhci_add_host(host);
 192         if (ret)
 193                 goto err_pltfm_free;
 194
 195         return 0;
 196
 197 err_pltfm_free:
 198         sdhci_pltfm_free(pdev);
 199 clk_disable_all:
 200         clk_disable_unprepare(clk_xin);
 201 clk_dis_ahb:
 202         clk_disable_unprepare(sdhci_arasan->clk_ahb);
 203
 204         return ret;
 205 }
 206
 207 static int sdhci_arasan_remove(struct platform_device *pdev)
 208 {
 209         struct sdhci_host *host = platform_get_drvdata(pdev);
 210         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 211         struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
 212
 213         clk_disable_unprepare(sdhci_arasan->clk_ahb);
 214
 215         return sdhci_pltfm_unregister(pdev);
 216 }
 217
 218 static const struct of_device_id sdhci_arasan_of_match[] = {
 219         { .compatible = "arasan,sdhci-8.9a" },
 220         { .compatible = "arasan,sdhci-5.1" },
 221         { .compatible = "arasan,sdhci-4.9a" },
 222         { }
 223 };
 224 MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
 225
 226 static struct platform_driver sdhci_arasan_driver = {
 227         .driver = {
 228                 .name = "sdhci-arasan",
 229                 .of_match_table = sdhci_arasan_of_match,
 230                 .pm = &sdhci_arasan_dev_pm_ops,
 231         },
 232         .probe = sdhci_arasan_probe,
 233         .remove = sdhci_arasan_remove,
 234 };
 235
 236 module_platform_driver(sdhci_arasan_driver);
 237
 238 MODULE_DESCRIPTION("Driver for the Arasan SDHCI Controller");
 239 MODULE_AUTHOR("Soeren Brinkmann <soren.brinkmann@xilinx.com>");
 240 MODULE_LICENSE("GPL");