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/gpio.h> 19 #include <linux/highmem.h> 20 #include <linux/module.h> 21 #include <linux/interrupt.h> 22 #include <linux/irq.h> 23 #include <linux/of.h> 24 #include <linux/of_gpio.h> 25 #include <linux/platform_device.h> 26 #include <linux/pm.h> 27 #include <linux/slab.h> 28 #include <linux/mmc/host.h> 29 #include <linux/mmc/slot-gpio.h> 30 #include <linux/io.h> 31 #include "sdhci.h" 32 33 struct spear_sdhci { 34 struct clk *clk; 35 int card_int_gpio; 36 }; 37 38 /* sdhci ops */ 39 static const struct sdhci_ops sdhci_pltfm_ops = { 40 .set_clock = sdhci_set_clock, 41 .set_bus_width = sdhci_set_bus_width, 42 .reset = sdhci_reset, 43 .set_uhs_signaling = sdhci_set_uhs_signaling, 44 }; 45 46 static void sdhci_probe_config_dt(struct device_node *np, 47 struct spear_sdhci *host) 48 { 49 int cd_gpio; 50 51 cd_gpio = of_get_named_gpio(np, "cd-gpios", 0); 52 if (!gpio_is_valid(cd_gpio)) 53 cd_gpio = -1; 54 55 host->card_int_gpio = cd_gpio; 56 } 57 58 static int sdhci_probe(struct platform_device *pdev) 59 { 60 struct sdhci_host *host; 61 struct resource *iomem; 62 struct spear_sdhci *sdhci; 63 struct device *dev; 64 int ret; 65 66 dev = pdev->dev.parent ? pdev->dev.parent : &pdev->dev; 67 host = sdhci_alloc_host(dev, sizeof(*sdhci)); 68 if (IS_ERR(host)) { 69 ret = PTR_ERR(host); 70 dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n"); 71 goto err; 72 } 73 74 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 75 host->ioaddr = devm_ioremap_resource(&pdev->dev, iomem); 76 if (IS_ERR(host->ioaddr)) { 77 ret = PTR_ERR(host->ioaddr); 78 dev_dbg(&pdev->dev, "unable to map iomem: %d\n", ret); 79 goto err_host; 80 } 81 82 host->hw_name = "sdhci"; 83 host->ops = &sdhci_pltfm_ops; 84 host->irq = platform_get_irq(pdev, 0); 85 if (host->irq <= 0) { 86 ret = -EINVAL; 87 goto err_host; 88 } 89 host->quirks = SDHCI_QUIRK_BROKEN_ADMA; 90 91 sdhci = sdhci_priv(host); 92 93 /* clk enable */ 94 sdhci->clk = devm_clk_get(&pdev->dev, NULL); 95 if (IS_ERR(sdhci->clk)) { 96 ret = PTR_ERR(sdhci->clk); 97 dev_dbg(&pdev->dev, "Error getting clock\n"); 98 goto err_host; 99 } 100 101 ret = clk_prepare_enable(sdhci->clk); 102 if (ret) { 103 dev_dbg(&pdev->dev, "Error enabling clock\n"); 104 goto err_host; 105 } 106 107 ret = clk_set_rate(sdhci->clk, 50000000); 108 if (ret) 109 dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n", 110 clk_get_rate(sdhci->clk)); 111 112 sdhci_probe_config_dt(pdev->dev.of_node, sdhci); 113 /* 114 * It is optional to use GPIOs for sdhci card detection. If 115 * sdhci->card_int_gpio < 0, then use original sdhci lines otherwise 116 * GPIO lines. We use the built-in GPIO support for this. 117 */ 118 if (sdhci->card_int_gpio >= 0) { 119 ret = mmc_gpio_request_cd(host->mmc, sdhci->card_int_gpio, 0); 120 if (ret < 0) { 121 dev_dbg(&pdev->dev, 122 "failed to request card-detect gpio%d\n", 123 sdhci->card_int_gpio); 124 goto disable_clk; 125 } 126 } 127 128 ret = sdhci_add_host(host); 129 if (ret) 130 goto disable_clk; 131 132 platform_set_drvdata(pdev, host); 133 134 return 0; 135 136 disable_clk: 137 clk_disable_unprepare(sdhci->clk); 138 err_host: 139 sdhci_free_host(host); 140 err: 141 dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret); 142 return ret; 143 } 144 145 static int sdhci_remove(struct platform_device *pdev) 146 { 147 struct sdhci_host *host = platform_get_drvdata(pdev); 148 struct spear_sdhci *sdhci = sdhci_priv(host); 149 int dead = 0; 150 u32 scratch; 151 152 scratch = readl(host->ioaddr + SDHCI_INT_STATUS); 153 if (scratch == (u32)-1) 154 dead = 1; 155 156 sdhci_remove_host(host, dead); 157 clk_disable_unprepare(sdhci->clk); 158 sdhci_free_host(host); 159 160 return 0; 161 } 162 163 #ifdef CONFIG_PM_SLEEP 164 static int sdhci_suspend(struct device *dev) 165 { 166 struct sdhci_host *host = dev_get_drvdata(dev); 167 struct spear_sdhci *sdhci = sdhci_priv(host); 168 int ret; 169 170 if (host->tuning_mode != SDHCI_TUNING_MODE_3) 171 mmc_retune_needed(host->mmc); 172 173 ret = sdhci_suspend_host(host); 174 if (!ret) 175 clk_disable(sdhci->clk); 176 177 return ret; 178 } 179 180 static int sdhci_resume(struct device *dev) 181 { 182 struct sdhci_host *host = dev_get_drvdata(dev); 183 struct spear_sdhci *sdhci = sdhci_priv(host); 184 int ret; 185 186 ret = clk_enable(sdhci->clk); 187 if (ret) { 188 dev_dbg(dev, "Resume: Error enabling clock\n"); 189 return ret; 190 } 191 192 return sdhci_resume_host(host); 193 } 194 #endif 195 196 static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume); 197 198 #ifdef CONFIG_OF 199 static const struct of_device_id sdhci_spear_id_table[] = { 200 { .compatible = "st,spear300-sdhci" }, 201 {} 202 }; 203 MODULE_DEVICE_TABLE(of, sdhci_spear_id_table); 204 #endif 205 206 static struct platform_driver sdhci_driver = { 207 .driver = { 208 .name = "sdhci", 209 .pm = &sdhci_pm_ops, 210 .of_match_table = of_match_ptr(sdhci_spear_id_table), 211 }, 212 .probe = sdhci_probe, 213 .remove = sdhci_remove, 214 }; 215 216 module_platform_driver(sdhci_driver); 217 218 MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver"); 219 MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>"); 220 MODULE_LICENSE("GPL v2"); 221