1 /* 2 * drivers/mmc/host/sdhci-spear.c 3 * 4 * Support of SDHCI platform devices for spear soc family 5 * 6 * Copyright (C) 2010 ST Microelectronics 7 * Viresh Kumar <vireshk@kernel.org> 8 * 9 * Inspired by sdhci-pltfm.c 10 * 11 * This file is licensed under the terms of the GNU General Public 12 * License version 2. This program is licensed "as is" without any 13 * 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 31 struct spear_sdhci { 32 struct clk *clk; 33 }; 34 35 /* sdhci ops */ 36 static 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 43 static 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 = -EINVAL; 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 we 97 * 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; 110 111 disable_clk: 112 clk_disable_unprepare(sdhci->clk); 113 err_host: 114 sdhci_free_host(host); 115 err: 116 dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret); 117 return ret; 118 } 119 120 static int 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 return 0; 136 } 137 138 #ifdef CONFIG_PM_SLEEP 139 static int sdhci_suspend(struct device *dev) 140 { 141 struct sdhci_host *host = dev_get_drvdata(dev); 142 struct spear_sdhci *sdhci = sdhci_priv(host); 143 int ret; 144 145 if (host->tuning_mode != SDHCI_TUNING_MODE_3) 146 mmc_retune_needed(host->mmc); 147 148 ret = sdhci_suspend_host(host); 149 if (!ret) 150 clk_disable(sdhci->clk); 151 152 return ret; 153 } 154 155 static int sdhci_resume(struct device *dev) 156 { 157 struct sdhci_host *host = dev_get_drvdata(dev); 158 struct spear_sdhci *sdhci = sdhci_priv(host); 159 int ret; 160 161 ret = clk_enable(sdhci->clk); 162 if (ret) { 163 dev_dbg(dev, "Resume: Error enabling clock\n"); 164 return ret; 165 } 166 167 return sdhci_resume_host(host); 168 } 169 #endif 170 171 static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume); 172 173 #ifdef CONFIG_OF 174 static const struct of_device_id sdhci_spear_id_table[] = { 175 { .compatible = "st,spear300-sdhci" }, 176 {} 177 }; 178 MODULE_DEVICE_TABLE(of, sdhci_spear_id_table); 179 #endif 180 181 static struct platform_driver sdhci_driver = { 182 .driver = { 183 .name = "sdhci", 184 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 185 .pm = &sdhci_pm_ops, 186 .of_match_table = of_match_ptr(sdhci_spear_id_table), 187 }, 188 .probe = sdhci_probe, 189 .remove = sdhci_remove, 190 }; 191 192 module_platform_driver(sdhci_driver); 193 194 MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver"); 195 MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>"); 196 MODULE_LICENSE("GPL v2"); 197