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1/*2 * drivers/mmc/host/sdhci-spear.c3 *4 * Support of SDHCI platform devices for spear soc family5 *6 * Copyright (C) 2010 ST Microelectronics7 * Viresh Kumar <vireshk@kernel.org>8 *9 * Inspired by sdhci-pltfm.c10 *11 * This file is licensed under the terms of the GNU General Public12 * License version 2. This program is licensed "as is" without any13 * warranty of any kind, whether express or implied.14 */15 16#include <linux/clk.h>17#include <linux/delay.h>18#include <linux/highmem.h>19#include <linux/module.h>20#include <linux/interrupt.h>21#include <linux/irq.h>22#include <linux/of.h>23#include <linux/platform_device.h>24#include <linux/pm.h>25#include <linux/slab.h>26#include <linux/mmc/host.h>27#include <linux/mmc/slot-gpio.h>28#include <linux/io.h>29#include "sdhci.h"30 31struct spear_sdhci {32 struct clk *clk;33};34 35/* sdhci ops */36static const struct sdhci_ops sdhci_pltfm_ops = {37 .set_clock = sdhci_set_clock,38 .set_bus_width = sdhci_set_bus_width,39 .reset = sdhci_reset,40 .set_uhs_signaling = sdhci_set_uhs_signaling,41};42 43static int sdhci_probe(struct platform_device *pdev)44{45 struct sdhci_host *host;46 struct spear_sdhci *sdhci;47 struct device *dev;48 int ret;49 50 dev = pdev->dev.parent ? pdev->dev.parent : &pdev->dev;51 host = sdhci_alloc_host(dev, sizeof(*sdhci));52 if (IS_ERR(host)) {53 ret = PTR_ERR(host);54 dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");55 goto err;56 }57 58 host->ioaddr = devm_platform_ioremap_resource(pdev, 0);59 if (IS_ERR(host->ioaddr)) {60 ret = PTR_ERR(host->ioaddr);61 dev_dbg(&pdev->dev, "unable to map iomem: %d\n", ret);62 goto err_host;63 }64 65 host->hw_name = "sdhci";66 host->ops = &sdhci_pltfm_ops;67 host->irq = platform_get_irq(pdev, 0);68 if (host->irq < 0) {69 ret = host->irq;70 goto err_host;71 }72 host->quirks = SDHCI_QUIRK_BROKEN_ADMA;73 74 sdhci = sdhci_priv(host);75 76 /* clk enable */77 sdhci->clk = devm_clk_get(&pdev->dev, NULL);78 if (IS_ERR(sdhci->clk)) {79 ret = PTR_ERR(sdhci->clk);80 dev_dbg(&pdev->dev, "Error getting clock\n");81 goto err_host;82 }83 84 ret = clk_prepare_enable(sdhci->clk);85 if (ret) {86 dev_dbg(&pdev->dev, "Error enabling clock\n");87 goto err_host;88 }89 90 ret = clk_set_rate(sdhci->clk, 50000000);91 if (ret)92 dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n",93 clk_get_rate(sdhci->clk));94 95 /*96 * It is optional to use GPIOs for sdhci card detection. If we97 * find a descriptor using slot GPIO, we use it.98 */99 ret = mmc_gpiod_request_cd(host->mmc, "cd", 0, false, 0);100 if (ret == -EPROBE_DEFER)101 goto disable_clk;102 103 ret = sdhci_add_host(host);104 if (ret)105 goto disable_clk;106 107 platform_set_drvdata(pdev, host);108 109 return 0;110 111disable_clk:112 clk_disable_unprepare(sdhci->clk);113err_host:114 sdhci_free_host(host);115err:116 dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);117 return ret;118}119 120static void sdhci_remove(struct platform_device *pdev)121{122 struct sdhci_host *host = platform_get_drvdata(pdev);123 struct spear_sdhci *sdhci = sdhci_priv(host);124 int dead = 0;125 u32 scratch;126 127 scratch = readl(host->ioaddr + SDHCI_INT_STATUS);128 if (scratch == (u32)-1)129 dead = 1;130 131 sdhci_remove_host(host, dead);132 clk_disable_unprepare(sdhci->clk);133 sdhci_free_host(host);134}135 136#ifdef CONFIG_PM_SLEEP137static int sdhci_suspend(struct device *dev)138{139 struct sdhci_host *host = dev_get_drvdata(dev);140 struct spear_sdhci *sdhci = sdhci_priv(host);141 int ret;142 143 if (host->tuning_mode != SDHCI_TUNING_MODE_3)144 mmc_retune_needed(host->mmc);145 146 ret = sdhci_suspend_host(host);147 if (!ret)148 clk_disable(sdhci->clk);149 150 return ret;151}152 153static int sdhci_resume(struct device *dev)154{155 struct sdhci_host *host = dev_get_drvdata(dev);156 struct spear_sdhci *sdhci = sdhci_priv(host);157 int ret;158 159 ret = clk_enable(sdhci->clk);160 if (ret) {161 dev_dbg(dev, "Resume: Error enabling clock\n");162 return ret;163 }164 165 return sdhci_resume_host(host);166}167#endif168 169static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume);170 171static const struct of_device_id sdhci_spear_id_table[] = {172 { .compatible = "st,spear300-sdhci" },173 {}174};175MODULE_DEVICE_TABLE(of, sdhci_spear_id_table);176 177static struct platform_driver sdhci_driver = {178 .driver = {179 .name = "sdhci",180 .probe_type = PROBE_PREFER_ASYNCHRONOUS,181 .pm = &sdhci_pm_ops,182 .of_match_table = sdhci_spear_id_table,183 },184 .probe = sdhci_probe,185 .remove_new = sdhci_remove,186};187 188module_platform_driver(sdhci_driver);189 190MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");191MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");192MODULE_LICENSE("GPL v2");193