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/module.h>
  17 #include <linux/init.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/clk.h>
  20 #include <linux/io.h>
  21 #include <linux/of.h>
  22 #include <linux/of_gpio.h>
  23 #include <linux/gpio.h>
  24 #include <linux/mmc/card.h>
  25 #include <linux/mmc/host.h>
  26 #include <linux/module.h>
  27
  28 #include <asm/gpio.h>
  29
  30 #include <mach/gpio-tegra.h>
  31 #include <mach/sdhci.h>
  32
  33 #include "sdhci-pltfm.h"
  34
  35 static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
  36 {
  37         u32 val;
  38
  39         if (unlikely(reg == SDHCI_PRESENT_STATE)) {
  40                 /* Use wp_gpio here instead? */
  41                 val = readl(host->ioaddr + reg);
  42                 return val | SDHCI_WRITE_PROTECT;
  43         }
  44
  45         return readl(host->ioaddr + reg);
  46 }
  47
  48 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
  49 {
  50         if (unlikely(reg == SDHCI_HOST_VERSION)) {
  51                 /* Erratum: Version register is invalid in HW. */
  52                 return SDHCI_SPEC_200;
  53         }
  54
  55         return readw(host->ioaddr + reg);
  56 }
  57
  58 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
  59 {
  60         /* Seems like we're getting spurious timeout and crc errors, so
  61          * disable signalling of them. In case of real errors software
  62          * timers should take care of eventually detecting them.
  63          */
  64         if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
  65                 val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
  66
  67         writel(val, host->ioaddr + reg);
  68
  69         if (unlikely(reg == SDHCI_INT_ENABLE)) {
  70                 /* Erratum: Must enable block gap interrupt detection */
  71                 u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
  72                 if (val & SDHCI_INT_CARD_INT)
  73                         gap_ctrl |= 0x8;
  74                 else
  75                         gap_ctrl &= ~0x8;
  76                 writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
  77         }
  78 }
  79
  80 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *sdhci)
  81 {
  82         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(sdhci);
  83         struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
  84
  85         if (!gpio_is_valid(plat->wp_gpio))
  86                 return -1;
  87
  88         return gpio_get_value(plat->wp_gpio);
  89 }
  90
  91 static irqreturn_t carddetect_irq(int irq, void *data)
  92 {
  93         struct sdhci_host *sdhost = (struct sdhci_host *)data;
  94
  95         tasklet_schedule(&sdhost->card_tasklet);
  96         return IRQ_HANDLED;
  97 };
  98
  99 static int tegra_sdhci_8bit(struct sdhci_host *host, int bus_width)
 100 {
 101         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 102         struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
 103         u32 ctrl;
 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 const struct of_device_id sdhci_tegra_dt_match[] __devinitdata = {
 137         { .compatible = "nvidia,tegra20-sdhci", },
 138         {}
 139 };
 140 MODULE_DEVICE_TABLE(of, sdhci_dt_ids);
 141
 142 static struct tegra_sdhci_platform_data * __devinit sdhci_tegra_dt_parse_pdata(
 143                                                 struct platform_device *pdev)
 144 {
 145         struct tegra_sdhci_platform_data *plat;
 146         struct device_node *np = pdev->dev.of_node;
 147
 148         if (!np)
 149                 return NULL;
 150
 151         plat = devm_kzalloc(&pdev->dev, sizeof(*plat), GFP_KERNEL);
 152         if (!plat) {
 153                 dev_err(&pdev->dev, "Can't allocate platform data\n");
 154                 return NULL;
 155         }
 156
 157         plat->cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
 158         plat->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
 159         plat->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
 160         if (of_find_property(np, "support-8bit", NULL))
 161                 plat->is_8bit = 1;
 162
 163         return plat;
 164 }
 165
 166 static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
 167 {
 168         struct sdhci_pltfm_host *pltfm_host;
 169         struct tegra_sdhci_platform_data *plat;
 170         struct sdhci_host *host;
 171         struct clk *clk;
 172         int rc;
 173
 174         host = sdhci_pltfm_init(pdev, &sdhci_tegra_pdata);
 175         if (IS_ERR(host))
 176                 return PTR_ERR(host);
 177
 178         pltfm_host = sdhci_priv(host);
 179
 180         plat = pdev->dev.platform_data;
 181
 182         if (plat == NULL)
 183                 plat = sdhci_tegra_dt_parse_pdata(pdev);
 184
 185         if (plat == NULL) {
 186                 dev_err(mmc_dev(host->mmc), "missing platform data\n");
 187                 rc = -ENXIO;
 188                 goto err_no_plat;
 189         }
 190
 191         pltfm_host->priv = plat;
 192
 193         if (gpio_is_valid(plat->power_gpio)) {
 194                 rc = gpio_request(plat->power_gpio, "sdhci_power");
 195                 if (rc) {
 196                         dev_err(mmc_dev(host->mmc),
 197                                 "failed to allocate power gpio\n");
 198                         goto err_power_req;
 199                 }
 200                 tegra_gpio_enable(plat->power_gpio);
 201                 gpio_direction_output(plat->power_gpio, 1);
 202         }
 203
 204         if (gpio_is_valid(plat->cd_gpio)) {
 205                 rc = gpio_request(plat->cd_gpio, "sdhci_cd");
 206                 if (rc) {
 207                         dev_err(mmc_dev(host->mmc),
 208                                 "failed to allocate cd gpio\n");
 209                         goto err_cd_req;
 210                 }
 211                 tegra_gpio_enable(plat->cd_gpio);
 212                 gpio_direction_input(plat->cd_gpio);
 213
 214                 rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
 215                                  IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 216                                  mmc_hostname(host->mmc), host);
 217
 218                 if (rc) {
 219                         dev_err(mmc_dev(host->mmc), "request irq error\n");
 220                         goto err_cd_irq_req;
 221                 }
 222
 223         }
 224
 225         if (gpio_is_valid(plat->wp_gpio)) {
 226                 rc = gpio_request(plat->wp_gpio, "sdhci_wp");
 227                 if (rc) {
 228                         dev_err(mmc_dev(host->mmc),
 229                                 "failed to allocate wp gpio\n");
 230                         goto err_wp_req;
 231                 }
 232                 tegra_gpio_enable(plat->wp_gpio);
 233                 gpio_direction_input(plat->wp_gpio);
 234         }
 235
 236         clk = clk_get(mmc_dev(host->mmc), NULL);
 237         if (IS_ERR(clk)) {
 238                 dev_err(mmc_dev(host->mmc), "clk err\n");
 239                 rc = PTR_ERR(clk);
 240                 goto err_clk_get;
 241         }
 242         clk_enable(clk);
 243         pltfm_host->clk = clk;
 244
 245         host->mmc->pm_caps = plat->pm_flags;
 246
 247         if (plat->is_8bit)
 248                 host->mmc->caps |= MMC_CAP_8_BIT_DATA;
 249
 250         rc = sdhci_add_host(host);
 251         if (rc)
 252                 goto err_add_host;
 253
 254         return 0;
 255
 256 err_add_host:
 257         clk_disable(pltfm_host->clk);
 258         clk_put(pltfm_host->clk);
 259 err_clk_get:
 260         if (gpio_is_valid(plat->wp_gpio)) {
 261                 tegra_gpio_disable(plat->wp_gpio);
 262                 gpio_free(plat->wp_gpio);
 263         }
 264 err_wp_req:
 265         if (gpio_is_valid(plat->cd_gpio))
 266                 free_irq(gpio_to_irq(plat->cd_gpio), host);
 267 err_cd_irq_req:
 268         if (gpio_is_valid(plat->cd_gpio)) {
 269                 tegra_gpio_disable(plat->cd_gpio);
 270                 gpio_free(plat->cd_gpio);
 271         }
 272 err_cd_req:
 273         if (gpio_is_valid(plat->power_gpio)) {
 274                 tegra_gpio_disable(plat->power_gpio);
 275                 gpio_free(plat->power_gpio);
 276         }
 277 err_power_req:
 278 err_no_plat:
 279         sdhci_pltfm_free(pdev);
 280         return rc;
 281 }
 282
 283 static int __devexit sdhci_tegra_remove(struct platform_device *pdev)
 284 {
 285         struct sdhci_host *host = platform_get_drvdata(pdev);
 286         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 287         struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
 288         int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
 289
 290         sdhci_remove_host(host, dead);
 291
 292         if (gpio_is_valid(plat->wp_gpio)) {
 293                 tegra_gpio_disable(plat->wp_gpio);
 294                 gpio_free(plat->wp_gpio);
 295         }
 296
 297         if (gpio_is_valid(plat->cd_gpio)) {
 298                 free_irq(gpio_to_irq(plat->cd_gpio), host);
 299                 tegra_gpio_disable(plat->cd_gpio);
 300                 gpio_free(plat->cd_gpio);
 301         }
 302
 303         if (gpio_is_valid(plat->power_gpio)) {
 304                 tegra_gpio_disable(plat->power_gpio);
 305                 gpio_free(plat->power_gpio);
 306         }
 307
 308         clk_disable(pltfm_host->clk);
 309         clk_put(pltfm_host->clk);
 310
 311         sdhci_pltfm_free(pdev);
 312
 313         return 0;
 314 }
 315
 316 static struct platform_driver sdhci_tegra_driver = {
 317         .driver         = {
 318                 .name   = "sdhci-tegra",
 319                 .owner  = THIS_MODULE,
 320                 .of_match_table = sdhci_tegra_dt_match,
 321                 .pm     = SDHCI_PLTFM_PMOPS,
 322         },
 323         .probe          = sdhci_tegra_probe,
 324         .remove         = __devexit_p(sdhci_tegra_remove),
 325 };
 326
 327 module_platform_driver(sdhci_tegra_driver);
 328
 329 MODULE_DESCRIPTION("SDHCI driver for Tegra");
 330 MODULE_AUTHOR(" Google, Inc.");
 331 MODULE_LICENSE("GPL v2");