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