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 };
  67
  68 #ifdef CONFIG_PM_SLEEP
  69 /**
  70  * sdhci_arasan_suspend - Suspend method for the driver
  71  * @dev:        Address of the device structure
  72  * Returns 0 on success and error value on error
  73  *
  74  * Put the device in a low power state.
  75  */
  76 static int sdhci_arasan_suspend(struct device *dev)
  77 {
  78         struct platform_device *pdev = to_platform_device(dev);
  79         struct sdhci_host *host = platform_get_drvdata(pdev);
  80         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  81         struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
  82         int ret;
  83
  84         ret = sdhci_suspend_host(host);
  85         if (ret)
  86                 return ret;
  87
  88         clk_disable(pltfm_host->clk);
  89         clk_disable(sdhci_arasan->clk_ahb);
  90
  91         return 0;
  92 }
  93
  94 /**
  95  * sdhci_arasan_resume - Resume method for the driver
  96  * @dev:        Address of the device structure
  97  * Returns 0 on success and error value on error
  98  *
  99  * Resume operation after suspend
 100  */
 101 static int sdhci_arasan_resume(struct device *dev)
 102 {
 103         struct platform_device *pdev = to_platform_device(dev);
 104         struct sdhci_host *host = platform_get_drvdata(pdev);
 105         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 106         struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
 107         int ret;
 108
 109         ret = clk_enable(sdhci_arasan->clk_ahb);
 110         if (ret) {
 111                 dev_err(dev, "Cannot enable AHB clock.\n");
 112                 return ret;
 113         }
 114
 115         ret = clk_enable(pltfm_host->clk);
 116         if (ret) {
 117                 dev_err(dev, "Cannot enable SD clock.\n");
 118                 clk_disable(sdhci_arasan->clk_ahb);
 119                 return ret;
 120         }
 121
 122         return sdhci_resume_host(host);
 123 }
 124 #endif /* ! CONFIG_PM_SLEEP */
 125
 126 static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
 127                          sdhci_arasan_resume);
 128
 129 static int sdhci_arasan_probe(struct platform_device *pdev)
 130 {
 131         int ret;
 132         struct clk *clk_xin;
 133         struct sdhci_host *host;
 134         struct sdhci_pltfm_host *pltfm_host;
 135         struct sdhci_arasan_data *sdhci_arasan;
 136
 137         sdhci_arasan = devm_kzalloc(&pdev->dev, sizeof(*sdhci_arasan),
 138                         GFP_KERNEL);
 139         if (!sdhci_arasan)
 140                 return -ENOMEM;
 141
 142         sdhci_arasan->clk_ahb = devm_clk_get(&pdev->dev, "clk_ahb");
 143         if (IS_ERR(sdhci_arasan->clk_ahb)) {
 144                 dev_err(&pdev->dev, "clk_ahb clock not found.\n");
 145                 return PTR_ERR(sdhci_arasan->clk_ahb);
 146         }
 147
 148         clk_xin = devm_clk_get(&pdev->dev, "clk_xin");
 149         if (IS_ERR(clk_xin)) {
 150                 dev_err(&pdev->dev, "clk_xin clock not found.\n");
 151                 return PTR_ERR(clk_xin);
 152         }
 153
 154         ret = clk_prepare_enable(sdhci_arasan->clk_ahb);
 155         if (ret) {
 156                 dev_err(&pdev->dev, "Unable to enable AHB clock.\n");
 157                 return ret;
 158         }
 159
 160         ret = clk_prepare_enable(clk_xin);
 161         if (ret) {
 162                 dev_err(&pdev->dev, "Unable to enable SD clock.\n");
 163                 goto clk_dis_ahb;
 164         }
 165
 166         host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata, 0);
 167         if (IS_ERR(host)) {
 168                 ret = PTR_ERR(host);
 169                 goto clk_disable_all;
 170         }
 171
 172         if (of_device_is_compatible(pdev->dev.of_node, "arasan,sdhci-4.9a")) {
 173                 host->quirks |= SDHCI_QUIRK_NO_HISPD_BIT;
 174                 host->quirks2 |= SDHCI_QUIRK2_HOST_NO_CMD23;
 175         }
 176
 177         sdhci_get_of_property(pdev);
 178         pltfm_host = sdhci_priv(host);
 179         pltfm_host->priv = sdhci_arasan;
 180         pltfm_host->clk = clk_xin;
 181
 182         ret = mmc_of_parse(host->mmc);
 183         if (ret) {
 184                 dev_err(&pdev->dev, "parsing dt failed (%u)\n", ret);
 185                 goto clk_disable_all;
 186         }
 187
 188         ret = sdhci_add_host(host);
 189         if (ret)
 190                 goto err_pltfm_free;
 191
 192         return 0;
 193
 194 err_pltfm_free:
 195         sdhci_pltfm_free(pdev);
 196 clk_disable_all:
 197         clk_disable_unprepare(clk_xin);
 198 clk_dis_ahb:
 199         clk_disable_unprepare(sdhci_arasan->clk_ahb);
 200
 201         return ret;
 202 }
 203
 204 static int sdhci_arasan_remove(struct platform_device *pdev)
 205 {
 206         struct sdhci_host *host = platform_get_drvdata(pdev);
 207         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 208         struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
 209
 210         clk_disable_unprepare(sdhci_arasan->clk_ahb);
 211
 212         return sdhci_pltfm_unregister(pdev);
 213 }
 214
 215 static const struct of_device_id sdhci_arasan_of_match[] = {
 216         { .compatible = "arasan,sdhci-8.9a" },
 217         { .compatible = "arasan,sdhci-4.9a" },
 218         { }
 219 };
 220 MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
 221
 222 static struct platform_driver sdhci_arasan_driver = {
 223         .driver = {
 224                 .name = "sdhci-arasan",
 225                 .of_match_table = sdhci_arasan_of_match,
 226                 .pm = &sdhci_arasan_dev_pm_ops,
 227         },
 228         .probe = sdhci_arasan_probe,
 229         .remove = sdhci_arasan_remove,
 230 };
 231
 232 module_platform_driver(sdhci_arasan_driver);
 233
 234 MODULE_DESCRIPTION("Driver for the Arasan SDHCI Controller");
 235 MODULE_AUTHOR("Soeren Brinkmann <soren.brinkmann@xilinx.com>");
 236 MODULE_LICENSE("GPL");