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