drivers/mmc/host/sdhci-st.c

   1 /*
   2  * Support for SDHCI on STMicroelectronics SoCs
   3  *
   4  * Copyright (C) 2014 STMicroelectronics Ltd
   5  * Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
   6  * Contributors: Peter Griffin <peter.griffin@linaro.org>
   7  *
   8  * Based on sdhci-cns3xxx.c
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  */
  20
  21 #include <linux/io.h>
  22 #include <linux/of.h>
  23 #include <linux/module.h>
  24 #include <linux/err.h>
  25 #include <linux/mmc/host.h>
  26
  27 #include "sdhci-pltfm.h"
  28
  29 static u32 sdhci_st_readl(struct sdhci_host *host, int reg)
  30 {
  31         u32 ret;
  32
  33         switch (reg) {
  34         case SDHCI_CAPABILITIES:
  35                 ret = readl_relaxed(host->ioaddr + reg);
  36                 /* Support 3.3V and 1.8V */
  37                 ret &= ~SDHCI_CAN_VDD_300;
  38                 break;
  39         default:
  40                 ret = readl_relaxed(host->ioaddr + reg);
  41         }
  42         return ret;
  43 }
  44
  45 static const struct sdhci_ops sdhci_st_ops = {
  46         .get_max_clock = sdhci_pltfm_clk_get_max_clock,
  47         .set_clock = sdhci_set_clock,
  48         .set_bus_width = sdhci_set_bus_width,
  49         .read_l = sdhci_st_readl,
  50         .reset = sdhci_reset,
  51 };
  52
  53 static const struct sdhci_pltfm_data sdhci_st_pdata = {
  54         .ops = &sdhci_st_ops,
  55         .quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC |
  56             SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
  57 };
  58
  59
  60 static int sdhci_st_probe(struct platform_device *pdev)
  61 {
  62         struct sdhci_host *host;
  63         struct sdhci_pltfm_host *pltfm_host;
  64         struct clk *clk;
  65         int ret = 0;
  66         u16 host_version;
  67
  68         clk =  devm_clk_get(&pdev->dev, "mmc");
  69         if (IS_ERR(clk)) {
  70                 dev_err(&pdev->dev, "Peripheral clk not found\n");
  71                 return PTR_ERR(clk);
  72         }
  73
  74         host = sdhci_pltfm_init(pdev, &sdhci_st_pdata, 0);
  75         if (IS_ERR(host)) {
  76                 dev_err(&pdev->dev, "Failed sdhci_pltfm_init\n");
  77                 return PTR_ERR(host);
  78         }
  79
  80         ret = mmc_of_parse(host->mmc);
  81
  82         if (ret) {
  83                 dev_err(&pdev->dev, "Failed mmc_of_parse\n");
  84                 return ret;
  85         }
  86
  87         clk_prepare_enable(clk);
  88
  89         pltfm_host = sdhci_priv(host);
  90         pltfm_host->clk = clk;
  91
  92         ret = sdhci_add_host(host);
  93         if (ret) {
  94                 dev_err(&pdev->dev, "Failed sdhci_add_host\n");
  95                 goto err_out;
  96         }
  97
  98         platform_set_drvdata(pdev, host);
  99
 100         host_version = readw_relaxed((host->ioaddr + SDHCI_HOST_VERSION));
 101
 102         dev_info(&pdev->dev, "SDHCI ST Initialised: Host Version: 0x%x Vendor Version 0x%x\n",
 103                 ((host_version & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT),
 104                 ((host_version & SDHCI_VENDOR_VER_MASK) >>
 105                 SDHCI_VENDOR_VER_SHIFT));
 106
 107         return 0;
 108
 109 err_out:
 110         clk_disable_unprepare(clk);
 111         sdhci_pltfm_free(pdev);
 112
 113         return ret;
 114 }
 115
 116 static int sdhci_st_remove(struct platform_device *pdev)
 117 {
 118         struct sdhci_host *host = platform_get_drvdata(pdev);
 119         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 120
 121         clk_disable_unprepare(pltfm_host->clk);
 122
 123         return sdhci_pltfm_unregister(pdev);
 124 }
 125
 126 #ifdef CONFIG_PM_SLEEP
 127 static int sdhci_st_suspend(struct device *dev)
 128 {
 129         struct sdhci_host *host = dev_get_drvdata(dev);
 130         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 131         int ret = sdhci_suspend_host(host);
 132
 133         if (ret)
 134                 goto out;
 135
 136         clk_disable_unprepare(pltfm_host->clk);
 137 out:
 138         return ret;
 139 }
 140
 141 static int sdhci_st_resume(struct device *dev)
 142 {
 143         struct sdhci_host *host = dev_get_drvdata(dev);
 144         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 145
 146         clk_prepare_enable(pltfm_host->clk);
 147
 148         return sdhci_resume_host(host);
 149 }
 150 #endif
 151
 152 static SIMPLE_DEV_PM_OPS(sdhci_st_pmops, sdhci_st_suspend, sdhci_st_resume);
 153
 154 static const struct of_device_id st_sdhci_match[] = {
 155         { .compatible = "st,sdhci" },
 156         {},
 157 };
 158
 159 MODULE_DEVICE_TABLE(of, st_sdhci_match);
 160
 161 static struct platform_driver sdhci_st_driver = {
 162         .probe = sdhci_st_probe,
 163         .remove = sdhci_st_remove,
 164         .driver = {
 165                    .name = "sdhci-st",
 166                    .pm = &sdhci_st_pmops,
 167                    .of_match_table = of_match_ptr(st_sdhci_match),
 168                   },
 169 };
 170
 171 module_platform_driver(sdhci_st_driver);
 172
 173 MODULE_DESCRIPTION("SDHCI driver for STMicroelectronics SoCs");
 174 MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
 175 MODULE_LICENSE("GPL v2");
 176 MODULE_ALIAS("platform:st-sdhci");