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 resource *iomem; 47 struct spear_sdhci *sdhci; 48 struct device *dev; 49 int ret; 50 51 dev = pdev->dev.parent ? pdev->dev.parent : &pdev->dev; 52 host = sdhci_alloc_host(dev, sizeof(*sdhci)); 53 if (IS_ERR(host)) { 54 ret = PTR_ERR(host); 55 dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n"); 56 goto err; 57 } 58 59 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 60 host->ioaddr = devm_ioremap_resource(&pdev->dev, iomem); 61 if (IS_ERR(host->ioaddr)) { 62 ret = PTR_ERR(host->ioaddr); 63 dev_dbg(&pdev->dev, "unable to map iomem: %d\n", ret); 64 goto err_host; 65 } 66 67 host->hw_name = "sdhci"; 68 host->ops = &sdhci_pltfm_ops; 69 host->irq = platform_get_irq(pdev, 0); 70 if (host->irq <= 0) { 71 ret = -EINVAL; 72 goto err_host; 73 } 74 host->quirks = SDHCI_QUIRK_BROKEN_ADMA; 75 76 sdhci = sdhci_priv(host); 77 78 /* clk enable */ 79 sdhci->clk = devm_clk_get(&pdev->dev, NULL); 80 if (IS_ERR(sdhci->clk)) { 81 ret = PTR_ERR(sdhci->clk); 82 dev_dbg(&pdev->dev, "Error getting clock\n"); 83 goto err_host; 84 } 85 86 ret = clk_prepare_enable(sdhci->clk); 87 if (ret) { 88 dev_dbg(&pdev->dev, "Error enabling clock\n"); 89 goto err_host; 90 } 91 92 ret = clk_set_rate(sdhci->clk, 50000000); 93 if (ret) 94 dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n", 95 clk_get_rate(sdhci->clk)); 96 97 /* 98 * It is optional to use GPIOs for sdhci card detection. If we 99 * find a descriptor using slot GPIO, we use it. 100 */ 101 ret = mmc_gpiod_request_cd(host->mmc, "cd", 0, false, 0, NULL); 102 if (ret == -EPROBE_DEFER) 103 goto disable_clk; 104 105 ret = sdhci_add_host(host); 106 if (ret) 107 goto disable_clk; 108 109 platform_set_drvdata(pdev, host); 110 111 return 0; 112 113 disable_clk: 114 clk_disable_unprepare(sdhci->clk); 115 err_host: 116 sdhci_free_host(host); 117 err: 118 dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret); 119 return ret; 120 } 121 122 static int sdhci_remove(struct platform_device *pdev) 123 { 124 struct sdhci_host *host = platform_get_drvdata(pdev); 125 struct spear_sdhci *sdhci = sdhci_priv(host); 126 int dead = 0; 127 u32 scratch; 128 129 scratch = readl(host->ioaddr + SDHCI_INT_STATUS); 130 if (scratch == (u32)-1) 131 dead = 1; 132 133 sdhci_remove_host(host, dead); 134 clk_disable_unprepare(sdhci->clk); 135 sdhci_free_host(host); 136 137 return 0; 138 } 139 140 #ifdef CONFIG_PM_SLEEP 141 static int sdhci_suspend(struct device *dev) 142 { 143 struct sdhci_host *host = dev_get_drvdata(dev); 144 struct spear_sdhci *sdhci = sdhci_priv(host); 145 int ret; 146 147 if (host->tuning_mode != SDHCI_TUNING_MODE_3) 148 mmc_retune_needed(host->mmc); 149 150 ret = sdhci_suspend_host(host); 151 if (!ret) 152 clk_disable(sdhci->clk); 153 154 return ret; 155 } 156 157 static int sdhci_resume(struct device *dev) 158 { 159 struct sdhci_host *host = dev_get_drvdata(dev); 160 struct spear_sdhci *sdhci = sdhci_priv(host); 161 int ret; 162 163 ret = clk_enable(sdhci->clk); 164 if (ret) { 165 dev_dbg(dev, "Resume: Error enabling clock\n"); 166 return ret; 167 } 168 169 return sdhci_resume_host(host); 170 } 171 #endif 172 173 static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume); 174 175 #ifdef CONFIG_OF 176 static const struct of_device_id sdhci_spear_id_table[] = { 177 { .compatible = "st,spear300-sdhci" }, 178 {} 179 }; 180 MODULE_DEVICE_TABLE(of, sdhci_spear_id_table); 181 #endif 182 183 static struct platform_driver sdhci_driver = { 184 .driver = { 185 .name = "sdhci", 186 .pm = &sdhci_pm_ops, 187 .of_match_table = of_match_ptr(sdhci_spear_id_table), 188 }, 189 .probe = sdhci_probe, 190 .remove = sdhci_remove, 191 }; 192 193 module_platform_driver(sdhci_driver); 194 195 MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver"); 196 MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>"); 197 MODULE_LICENSE("GPL v2"); 198