drivers/mmc/host/sdhci-tegra.c

   1 /*
   2  * Copyright (C) 2010 Google, Inc.
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #include <linux/err.h>
  16 #include <linux/init.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/clk.h>
  19 #include <linux/io.h>
  20 #include <linux/gpio.h>
  21 #include <linux/mmc/card.h>
  22 #include <linux/mmc/host.h>
  23
  24 #include <mach/gpio.h>
  25 #include <mach/sdhci.h>
  26
  27 #include "sdhci-pltfm.h"
  28
  29 static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
  30 {
  31         u32 val;
  32
  33         if (unlikely(reg == SDHCI_PRESENT_STATE)) {
  34                 /* Use wp_gpio here instead? */
  35                 val = readl(host->ioaddr + reg);
  36                 return val | SDHCI_WRITE_PROTECT;
  37         }
  38
  39         return readl(host->ioaddr + reg);
  40 }
  41
  42 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
  43 {
  44         if (unlikely(reg == SDHCI_HOST_VERSION)) {
  45                 /* Erratum: Version register is invalid in HW. */
  46                 return SDHCI_SPEC_200;
  47         }
  48
  49         return readw(host->ioaddr + reg);
  50 }
  51
  52 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
  53 {
  54         /* Seems like we're getting spurious timeout and crc errors, so
  55          * disable signalling of them. In case of real errors software
  56          * timers should take care of eventually detecting them.
  57          */
  58         if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
  59                 val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
  60
  61         writel(val, host->ioaddr + reg);
  62
  63         if (unlikely(reg == SDHCI_INT_ENABLE)) {
  64                 /* Erratum: Must enable block gap interrupt detection */
  65                 u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
  66                 if (val & SDHCI_INT_CARD_INT)
  67                         gap_ctrl |= 0x8;
  68                 else
  69                         gap_ctrl &= ~0x8;
  70                 writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
  71         }
  72 }
  73
  74 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *sdhci)
  75 {
  76         struct platform_device *pdev = to_platform_device(mmc_dev(sdhci->mmc));
  77         struct tegra_sdhci_platform_data *plat;
  78
  79         plat = pdev->dev.platform_data;
  80
  81         if (!gpio_is_valid(plat->wp_gpio))
  82                 return -1;
  83
  84         return gpio_get_value(plat->wp_gpio);
  85 }
  86
  87 static irqreturn_t carddetect_irq(int irq, void *data)
  88 {
  89         struct sdhci_host *sdhost = (struct sdhci_host *)data;
  90
  91         tasklet_schedule(&sdhost->card_tasklet);
  92         return IRQ_HANDLED;
  93 };
  94
  95 static int tegra_sdhci_8bit(struct sdhci_host *host, int bus_width)
  96 {
  97         struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
  98         struct tegra_sdhci_platform_data *plat;
  99         u32 ctrl;
 100
 101         plat = pdev->dev.platform_data;
 102
 103         ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
 104         if (plat->is_8bit && bus_width == MMC_BUS_WIDTH_8) {
 105                 ctrl &= ~SDHCI_CTRL_4BITBUS;
 106                 ctrl |= SDHCI_CTRL_8BITBUS;
 107         } else {
 108                 ctrl &= ~SDHCI_CTRL_8BITBUS;
 109                 if (bus_width == MMC_BUS_WIDTH_4)
 110                         ctrl |= SDHCI_CTRL_4BITBUS;
 111                 else
 112                         ctrl &= ~SDHCI_CTRL_4BITBUS;
 113         }
 114         sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 115         return 0;
 116 }
 117
 118 static struct sdhci_ops tegra_sdhci_ops = {
 119         .get_ro     = tegra_sdhci_get_ro,
 120         .read_l     = tegra_sdhci_readl,
 121         .read_w     = tegra_sdhci_readw,
 122         .write_l    = tegra_sdhci_writel,
 123         .platform_8bit_width = tegra_sdhci_8bit,
 124 };
 125
 126 static struct sdhci_pltfm_data sdhci_tegra_pdata = {
 127         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 128                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 129                   SDHCI_QUIRK_NO_HISPD_BIT |
 130                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
 131         .ops  = &tegra_sdhci_ops,
 132 };
 133
 134 static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
 135 {
 136         struct sdhci_pltfm_host *pltfm_host;
 137         struct tegra_sdhci_platform_data *plat;
 138         struct sdhci_host *host;
 139         struct clk *clk;
 140         int rc;
 141
 142         host = sdhci_pltfm_init(pdev, &sdhci_tegra_pdata);
 143         if (IS_ERR(host))
 144                 return PTR_ERR(host);
 145
 146         pltfm_host = sdhci_priv(host);
 147
 148         plat = pdev->dev.platform_data;
 149
 150         if (plat == NULL) {
 151                 dev_err(mmc_dev(host->mmc), "missing platform data\n");
 152                 rc = -ENXIO;
 153                 goto err_no_plat;
 154         }
 155
 156         if (gpio_is_valid(plat->power_gpio)) {
 157                 rc = gpio_request(plat->power_gpio, "sdhci_power");
 158                 if (rc) {
 159                         dev_err(mmc_dev(host->mmc),
 160                                 "failed to allocate power gpio\n");
 161                         goto err_power_req;
 162                 }
 163                 tegra_gpio_enable(plat->power_gpio);
 164                 gpio_direction_output(plat->power_gpio, 1);
 165         }
 166
 167         if (gpio_is_valid(plat->cd_gpio)) {
 168                 rc = gpio_request(plat->cd_gpio, "sdhci_cd");
 169                 if (rc) {
 170                         dev_err(mmc_dev(host->mmc),
 171                                 "failed to allocate cd gpio\n");
 172                         goto err_cd_req;
 173                 }
 174                 tegra_gpio_enable(plat->cd_gpio);
 175                 gpio_direction_input(plat->cd_gpio);
 176
 177                 rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
 178                                  IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 179                                  mmc_hostname(host->mmc), host);
 180
 181                 if (rc) {
 182                         dev_err(mmc_dev(host->mmc), "request irq error\n");
 183                         goto err_cd_irq_req;
 184                 }
 185
 186         }
 187
 188         if (gpio_is_valid(plat->wp_gpio)) {
 189                 rc = gpio_request(plat->wp_gpio, "sdhci_wp");
 190                 if (rc) {
 191                         dev_err(mmc_dev(host->mmc),
 192                                 "failed to allocate wp gpio\n");
 193                         goto err_wp_req;
 194                 }
 195                 tegra_gpio_enable(plat->wp_gpio);
 196                 gpio_direction_input(plat->wp_gpio);
 197         }
 198
 199         clk = clk_get(mmc_dev(host->mmc), NULL);
 200         if (IS_ERR(clk)) {
 201                 dev_err(mmc_dev(host->mmc), "clk err\n");
 202                 rc = PTR_ERR(clk);
 203                 goto err_clk_get;
 204         }
 205         clk_enable(clk);
 206         pltfm_host->clk = clk;
 207
 208         host->mmc->pm_caps = plat->pm_flags;
 209
 210         if (plat->is_8bit)
 211                 host->mmc->caps |= MMC_CAP_8_BIT_DATA;
 212
 213         rc = sdhci_add_host(host);
 214         if (rc)
 215                 goto err_add_host;
 216
 217         return 0;
 218
 219 err_add_host:
 220         clk_disable(pltfm_host->clk);
 221         clk_put(pltfm_host->clk);
 222 err_clk_get:
 223         if (gpio_is_valid(plat->wp_gpio)) {
 224                 tegra_gpio_disable(plat->wp_gpio);
 225                 gpio_free(plat->wp_gpio);
 226         }
 227 err_wp_req:
 228         if (gpio_is_valid(plat->cd_gpio))
 229                 free_irq(gpio_to_irq(plat->cd_gpio), host);
 230 err_cd_irq_req:
 231         if (gpio_is_valid(plat->cd_gpio)) {
 232                 tegra_gpio_disable(plat->cd_gpio);
 233                 gpio_free(plat->cd_gpio);
 234         }
 235 err_cd_req:
 236         if (gpio_is_valid(plat->power_gpio)) {
 237                 tegra_gpio_disable(plat->power_gpio);
 238                 gpio_free(plat->power_gpio);
 239         }
 240 err_power_req:
 241 err_no_plat:
 242         sdhci_pltfm_free(pdev);
 243         return rc;
 244 }
 245
 246 static int __devexit sdhci_tegra_remove(struct platform_device *pdev)
 247 {
 248         struct sdhci_host *host = platform_get_drvdata(pdev);
 249         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 250         struct tegra_sdhci_platform_data *plat;
 251         int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
 252
 253         sdhci_remove_host(host, dead);
 254
 255         plat = pdev->dev.platform_data;
 256
 257         if (gpio_is_valid(plat->wp_gpio)) {
 258                 tegra_gpio_disable(plat->wp_gpio);
 259                 gpio_free(plat->wp_gpio);
 260         }
 261
 262         if (gpio_is_valid(plat->cd_gpio)) {
 263                 free_irq(gpio_to_irq(plat->cd_gpio), host);
 264                 tegra_gpio_disable(plat->cd_gpio);
 265                 gpio_free(plat->cd_gpio);
 266         }
 267
 268         if (gpio_is_valid(plat->power_gpio)) {
 269                 tegra_gpio_disable(plat->power_gpio);
 270                 gpio_free(plat->power_gpio);
 271         }
 272
 273         clk_disable(pltfm_host->clk);
 274         clk_put(pltfm_host->clk);
 275
 276         sdhci_pltfm_free(pdev);
 277
 278         return 0;
 279 }
 280
 281 static struct platform_driver sdhci_tegra_driver = {
 282         .driver         = {
 283                 .name   = "sdhci-tegra",
 284                 .owner  = THIS_MODULE,
 285         },
 286         .probe          = sdhci_tegra_probe,
 287         .remove         = __devexit_p(sdhci_tegra_remove),
 288 #ifdef CONFIG_PM
 289         .suspend        = sdhci_pltfm_suspend,
 290         .resume         = sdhci_pltfm_resume,
 291 #endif
 292 };
 293
 294 static int __init sdhci_tegra_init(void)
 295 {
 296         return platform_driver_register(&sdhci_tegra_driver);
 297 }
 298 module_init(sdhci_tegra_init);
 299
 300 static void __exit sdhci_tegra_exit(void)
 301 {
 302         platform_driver_unregister(&sdhci_tegra_driver);
 303 }
 304 module_exit(sdhci_tegra_exit);
 305
 306 MODULE_DESCRIPTION("SDHCI driver for Tegra");
 307 MODULE_AUTHOR(" Google, Inc.");
 308 MODULE_LICENSE("GPL v2");