drivers/mmc/host/sdhci-spear.c

   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 <viresh.linux@gmail.com>
   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/sdhci-spear.h>
  30 #include <linux/io.h>
  31 #include "sdhci.h"
  32
  33 struct spear_sdhci {
  34         struct clk *clk;
  35         struct sdhci_plat_data *data;
  36 };
  37
  38 /* sdhci ops */
  39 static const struct sdhci_ops sdhci_pltfm_ops = {
  40         /* Nothing to do for now. */
  41 };
  42
  43 /* gpio card detection interrupt handler */
  44 static irqreturn_t sdhci_gpio_irq(int irq, void *dev_id)
  45 {
  46         struct platform_device *pdev = dev_id;
  47         struct sdhci_host *host = platform_get_drvdata(pdev);
  48         struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
  49         unsigned long gpio_irq_type;
  50         int val;
  51
  52         val = gpio_get_value(sdhci->data->card_int_gpio);
  53
  54         /* val == 1 -> card removed, val == 0 -> card inserted */
  55         /* if card removed - set irq for low level, else vice versa */
  56         gpio_irq_type = val ? IRQF_TRIGGER_LOW : IRQF_TRIGGER_HIGH;
  57         irq_set_irq_type(irq, gpio_irq_type);
  58
  59         if (sdhci->data->card_power_gpio >= 0) {
  60                 if (!sdhci->data->power_always_enb) {
  61                         /* if card inserted, give power, otherwise remove it */
  62                         val = sdhci->data->power_active_high ? !val : val ;
  63                         gpio_set_value(sdhci->data->card_power_gpio, val);
  64                 }
  65         }
  66
  67         /* inform sdhci driver about card insertion/removal */
  68         tasklet_schedule(&host->card_tasklet);
  69
  70         return IRQ_HANDLED;
  71 }
  72
  73 #ifdef CONFIG_OF
  74 static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev)
  75 {
  76         struct device_node *np = pdev->dev.of_node;
  77         struct sdhci_plat_data *pdata = NULL;
  78         int cd_gpio;
  79
  80         cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
  81         if (!gpio_is_valid(cd_gpio))
  82                 cd_gpio = -1;
  83
  84         /* If pdata is required */
  85         if (cd_gpio != -1) {
  86                 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
  87                 if (!pdata) {
  88                         dev_err(&pdev->dev, "DT: kzalloc failed\n");
  89                         return ERR_PTR(-ENOMEM);
  90                 }
  91         }
  92
  93         pdata->card_int_gpio = cd_gpio;
  94
  95         return pdata;
  96 }
  97 #else
  98 static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev)
  99 {
 100         return ERR_PTR(-ENOSYS);
 101 }
 102 #endif
 103
 104 static int sdhci_probe(struct platform_device *pdev)
 105 {
 106         struct device_node *np = pdev->dev.of_node;
 107         struct sdhci_host *host;
 108         struct resource *iomem;
 109         struct spear_sdhci *sdhci;
 110         int ret;
 111
 112         iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 113         if (!iomem) {
 114                 ret = -ENOMEM;
 115                 dev_dbg(&pdev->dev, "memory resource not defined\n");
 116                 goto err;
 117         }
 118
 119         if (!devm_request_mem_region(&pdev->dev, iomem->start,
 120                                 resource_size(iomem), "spear-sdhci")) {
 121                 ret = -EBUSY;
 122                 dev_dbg(&pdev->dev, "cannot request region\n");
 123                 goto err;
 124         }
 125
 126         sdhci = devm_kzalloc(&pdev->dev, sizeof(*sdhci), GFP_KERNEL);
 127         if (!sdhci) {
 128                 ret = -ENOMEM;
 129                 dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");
 130                 goto err;
 131         }
 132
 133         /* clk enable */
 134         sdhci->clk = clk_get(&pdev->dev, NULL);
 135         if (IS_ERR(sdhci->clk)) {
 136                 ret = PTR_ERR(sdhci->clk);
 137                 dev_dbg(&pdev->dev, "Error getting clock\n");
 138                 goto err;
 139         }
 140
 141         ret = clk_prepare_enable(sdhci->clk);
 142         if (ret) {
 143                 dev_dbg(&pdev->dev, "Error enabling clock\n");
 144                 goto put_clk;
 145         }
 146
 147         ret = clk_set_rate(sdhci->clk, 50000000);
 148         if (ret)
 149                 dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n",
 150                                 clk_get_rate(sdhci->clk));
 151
 152         if (np) {
 153                 sdhci->data = sdhci_probe_config_dt(pdev);
 154                 if (IS_ERR(sdhci->data)) {
 155                         dev_err(&pdev->dev, "DT: Failed to get pdata\n");
 156                         return -ENODEV;
 157                 }
 158         } else {
 159                 sdhci->data = dev_get_platdata(&pdev->dev);
 160         }
 161
 162         pdev->dev.platform_data = sdhci;
 163
 164         if (pdev->dev.parent)
 165                 host = sdhci_alloc_host(pdev->dev.parent, 0);
 166         else
 167                 host = sdhci_alloc_host(&pdev->dev, 0);
 168
 169         if (IS_ERR(host)) {
 170                 ret = PTR_ERR(host);
 171                 dev_dbg(&pdev->dev, "error allocating host\n");
 172                 goto disable_clk;
 173         }
 174
 175         host->hw_name = "sdhci";
 176         host->ops = &sdhci_pltfm_ops;
 177         host->irq = platform_get_irq(pdev, 0);
 178         host->quirks = SDHCI_QUIRK_BROKEN_ADMA;
 179
 180         host->ioaddr = devm_ioremap(&pdev->dev, iomem->start,
 181                         resource_size(iomem));
 182         if (!host->ioaddr) {
 183                 ret = -ENOMEM;
 184                 dev_dbg(&pdev->dev, "failed to remap registers\n");
 185                 goto free_host;
 186         }
 187
 188         ret = sdhci_add_host(host);
 189         if (ret) {
 190                 dev_dbg(&pdev->dev, "error adding host\n");
 191                 goto free_host;
 192         }
 193
 194         platform_set_drvdata(pdev, host);
 195
 196         /*
 197          * It is optional to use GPIOs for sdhci Power control & sdhci card
 198          * interrupt detection. If sdhci->data is NULL, then use original sdhci
 199          * lines otherwise GPIO lines.
 200          * If GPIO is selected for power control, then power should be disabled
 201          * after card removal and should be enabled when card insertion
 202          * interrupt occurs
 203          */
 204         if (!sdhci->data)
 205                 return 0;
 206
 207         if (sdhci->data->card_power_gpio >= 0) {
 208                 int val = 0;
 209
 210                 ret = devm_gpio_request(&pdev->dev,
 211                                 sdhci->data->card_power_gpio, "sdhci");
 212                 if (ret < 0) {
 213                         dev_dbg(&pdev->dev, "gpio request fail: %d\n",
 214                                         sdhci->data->card_power_gpio);
 215                         goto set_drvdata;
 216                 }
 217
 218                 if (sdhci->data->power_always_enb)
 219                         val = sdhci->data->power_active_high;
 220                 else
 221                         val = !sdhci->data->power_active_high;
 222
 223                 ret = gpio_direction_output(sdhci->data->card_power_gpio, val);
 224                 if (ret) {
 225                         dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
 226                                         sdhci->data->card_power_gpio);
 227                         goto set_drvdata;
 228                 }
 229         }
 230
 231         if (sdhci->data->card_int_gpio >= 0) {
 232                 ret = devm_gpio_request(&pdev->dev, sdhci->data->card_int_gpio,
 233                                 "sdhci");
 234                 if (ret < 0) {
 235                         dev_dbg(&pdev->dev, "gpio request fail: %d\n",
 236                                         sdhci->data->card_int_gpio);
 237                         goto set_drvdata;
 238                 }
 239
 240                 ret = gpio_direction_input(sdhci->data->card_int_gpio);
 241                 if (ret) {
 242                         dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
 243                                         sdhci->data->card_int_gpio);
 244                         goto set_drvdata;
 245                 }
 246                 ret = devm_request_irq(&pdev->dev,
 247                                 gpio_to_irq(sdhci->data->card_int_gpio),
 248                                 sdhci_gpio_irq, IRQF_TRIGGER_LOW,
 249                                 mmc_hostname(host->mmc), pdev);
 250                 if (ret) {
 251                         dev_dbg(&pdev->dev, "gpio request irq fail: %d\n",
 252                                         sdhci->data->card_int_gpio);
 253                         goto set_drvdata;
 254                 }
 255
 256         }
 257
 258         return 0;
 259
 260 set_drvdata:
 261         sdhci_remove_host(host, 1);
 262 free_host:
 263         sdhci_free_host(host);
 264 disable_clk:
 265         clk_disable_unprepare(sdhci->clk);
 266 put_clk:
 267         clk_put(sdhci->clk);
 268 err:
 269         dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);
 270         return ret;
 271 }
 272
 273 static int sdhci_remove(struct platform_device *pdev)
 274 {
 275         struct sdhci_host *host = platform_get_drvdata(pdev);
 276         struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
 277         int dead = 0;
 278         u32 scratch;
 279
 280         scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
 281         if (scratch == (u32)-1)
 282                 dead = 1;
 283
 284         sdhci_remove_host(host, dead);
 285         sdhci_free_host(host);
 286         clk_disable_unprepare(sdhci->clk);
 287         clk_put(sdhci->clk);
 288
 289         return 0;
 290 }
 291
 292 #ifdef CONFIG_PM_SLEEP
 293 static int sdhci_suspend(struct device *dev)
 294 {
 295         struct sdhci_host *host = dev_get_drvdata(dev);
 296         struct spear_sdhci *sdhci = dev_get_platdata(dev);
 297         int ret;
 298
 299         ret = sdhci_suspend_host(host);
 300         if (!ret)
 301                 clk_disable(sdhci->clk);
 302
 303         return ret;
 304 }
 305
 306 static int sdhci_resume(struct device *dev)
 307 {
 308         struct sdhci_host *host = dev_get_drvdata(dev);
 309         struct spear_sdhci *sdhci = dev_get_platdata(dev);
 310         int ret;
 311
 312         ret = clk_enable(sdhci->clk);
 313         if (ret) {
 314                 dev_dbg(dev, "Resume: Error enabling clock\n");
 315                 return ret;
 316         }
 317
 318         return sdhci_resume_host(host);
 319 }
 320 #endif
 321
 322 static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume);
 323
 324 #ifdef CONFIG_OF
 325 static const struct of_device_id sdhci_spear_id_table[] = {
 326         { .compatible = "st,spear300-sdhci" },
 327         {}
 328 };
 329 MODULE_DEVICE_TABLE(of, sdhci_spear_id_table);
 330 #endif
 331
 332 static struct platform_driver sdhci_driver = {
 333         .driver = {
 334                 .name   = "sdhci",
 335                 .owner  = THIS_MODULE,
 336                 .pm     = &sdhci_pm_ops,
 337                 .of_match_table = of_match_ptr(sdhci_spear_id_table),
 338         },
 339         .probe          = sdhci_probe,
 340         .remove         = sdhci_remove,
 341 };
 342
 343 module_platform_driver(sdhci_driver);
 344
 345 MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");
 346 MODULE_AUTHOR("Viresh Kumar <viresh.linux@gmail.com>");
 347 MODULE_LICENSE("GPL v2");