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.h"
  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
 120 static int tegra_sdhci_pltfm_init(struct sdhci_host *host,
 121                                   struct sdhci_pltfm_data *pdata)
 122 {
 123         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 124         struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
 125         struct tegra_sdhci_platform_data *plat;
 126         struct clk *clk;
 127         int rc;
 128
 129         plat = pdev->dev.platform_data;
 130         if (plat == NULL) {
 131                 dev_err(mmc_dev(host->mmc), "missing platform data\n");
 132                 return -ENXIO;
 133         }
 134
 135         if (gpio_is_valid(plat->power_gpio)) {
 136                 rc = gpio_request(plat->power_gpio, "sdhci_power");
 137                 if (rc) {
 138                         dev_err(mmc_dev(host->mmc),
 139                                 "failed to allocate power gpio\n");
 140                         goto out;
 141                 }
 142                 tegra_gpio_enable(plat->power_gpio);
 143                 gpio_direction_output(plat->power_gpio, 1);
 144         }
 145
 146         if (gpio_is_valid(plat->cd_gpio)) {
 147                 rc = gpio_request(plat->cd_gpio, "sdhci_cd");
 148                 if (rc) {
 149                         dev_err(mmc_dev(host->mmc),
 150                                 "failed to allocate cd gpio\n");
 151                         goto out_power;
 152                 }
 153                 tegra_gpio_enable(plat->cd_gpio);
 154                 gpio_direction_input(plat->cd_gpio);
 155
 156                 rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
 157                                  IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 158                                  mmc_hostname(host->mmc), host);
 159
 160                 if (rc) {
 161                         dev_err(mmc_dev(host->mmc), "request irq error\n");
 162                         goto out_cd;
 163                 }
 164
 165         }
 166
 167         if (gpio_is_valid(plat->wp_gpio)) {
 168                 rc = gpio_request(plat->wp_gpio, "sdhci_wp");
 169                 if (rc) {
 170                         dev_err(mmc_dev(host->mmc),
 171                                 "failed to allocate wp gpio\n");
 172                         goto out_irq;
 173                 }
 174                 tegra_gpio_enable(plat->wp_gpio);
 175                 gpio_direction_input(plat->wp_gpio);
 176         }
 177
 178         clk = clk_get(mmc_dev(host->mmc), NULL);
 179         if (IS_ERR(clk)) {
 180                 dev_err(mmc_dev(host->mmc), "clk err\n");
 181                 rc = PTR_ERR(clk);
 182                 goto out_wp;
 183         }
 184         clk_enable(clk);
 185         pltfm_host->clk = clk;
 186
 187         host->mmc->pm_caps = plat->pm_flags;
 188
 189         if (plat->is_8bit)
 190                 host->mmc->caps |= MMC_CAP_8_BIT_DATA;
 191
 192         return 0;
 193
 194 out_wp:
 195         if (gpio_is_valid(plat->wp_gpio)) {
 196                 tegra_gpio_disable(plat->wp_gpio);
 197                 gpio_free(plat->wp_gpio);
 198         }
 199
 200 out_irq:
 201         if (gpio_is_valid(plat->cd_gpio))
 202                 free_irq(gpio_to_irq(plat->cd_gpio), host);
 203 out_cd:
 204         if (gpio_is_valid(plat->cd_gpio)) {
 205                 tegra_gpio_disable(plat->cd_gpio);
 206                 gpio_free(plat->cd_gpio);
 207         }
 208
 209 out_power:
 210         if (gpio_is_valid(plat->power_gpio)) {
 211                 tegra_gpio_disable(plat->power_gpio);
 212                 gpio_free(plat->power_gpio);
 213         }
 214
 215 out:
 216         return rc;
 217 }
 218
 219 static void tegra_sdhci_pltfm_exit(struct sdhci_host *host)
 220 {
 221         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 222         struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
 223         struct tegra_sdhci_platform_data *plat;
 224
 225         plat = pdev->dev.platform_data;
 226
 227         if (gpio_is_valid(plat->wp_gpio)) {
 228                 tegra_gpio_disable(plat->wp_gpio);
 229                 gpio_free(plat->wp_gpio);
 230         }
 231
 232         if (gpio_is_valid(plat->cd_gpio)) {
 233                 free_irq(gpio_to_irq(plat->cd_gpio), host);
 234                 tegra_gpio_disable(plat->cd_gpio);
 235                 gpio_free(plat->cd_gpio);
 236         }
 237
 238         if (gpio_is_valid(plat->power_gpio)) {
 239                 tegra_gpio_disable(plat->power_gpio);
 240                 gpio_free(plat->power_gpio);
 241         }
 242
 243         clk_disable(pltfm_host->clk);
 244         clk_put(pltfm_host->clk);
 245 }
 246
 247 static struct sdhci_ops tegra_sdhci_ops = {
 248         .get_ro     = tegra_sdhci_get_ro,
 249         .read_l     = tegra_sdhci_readl,
 250         .read_w     = tegra_sdhci_readw,
 251         .write_l    = tegra_sdhci_writel,
 252         .platform_8bit_width = tegra_sdhci_8bit,
 253 };
 254
 255 struct sdhci_pltfm_data sdhci_tegra_pdata = {
 256         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 257                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 258                   SDHCI_QUIRK_NO_HISPD_BIT |
 259                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
 260         .ops  = &tegra_sdhci_ops,
 261         .init = tegra_sdhci_pltfm_init,
 262         .exit = tegra_sdhci_pltfm_exit,
 263 };