arch/arm/mach-u300/mmc.c

   1 /*
   2  *
   3  * arch/arm/mach-u300/mmc.c
   4  *
   5  *
   6  * Copyright (C) 2009 ST-Ericsson AB
   7  * License terms: GNU General Public License (GPL) version 2
   8  *
   9  * Author: Linus Walleij <linus.walleij@stericsson.com>
  10  * Author: Johan Lundin <johan.lundin@stericsson.com>
  11  * Author: Jonas Aaberg <jonas.aberg@stericsson.com>
  12  */
  13 #include <linux/device.h>
  14 #include <linux/amba/bus.h>
  15 #include <linux/mmc/host.h>
  16 #include <linux/input.h>
  17 #include <linux/workqueue.h>
  18 #include <linux/delay.h>
  19 #include <linux/regulator/consumer.h>
  20 #include <linux/regulator/machine.h>
  21 #include <linux/gpio.h>
  22 #include <linux/amba/mmci.h>
  23
  24 #include "mmc.h"
  25 #include "padmux.h"
  26
  27 struct mmci_card_event {
  28         struct input_dev *mmc_input;
  29         int mmc_inserted;
  30         struct work_struct workq;
  31         struct mmci_platform_data mmc0_plat_data;
  32 };
  33
  34 static unsigned int mmc_status(struct device *dev)
  35 {
  36         struct mmci_card_event *mmci_card = container_of(
  37                 dev->platform_data,
  38                 struct mmci_card_event, mmc0_plat_data);
  39
  40         return mmci_card->mmc_inserted;
  41 }
  42
  43 static int mmci_callback(void *data)
  44 {
  45         struct mmci_card_event *mmci_card = data;
  46
  47         disable_irq_on_gpio_pin(U300_GPIO_PIN_MMC_CD);
  48         schedule_work(&mmci_card->workq);
  49
  50         return 0;
  51 }
  52
  53
  54 static ssize_t gpio_show(struct device *dev, struct device_attribute *attr,
  55                   char *buf)
  56 {
  57         struct mmci_card_event *mmci_card = container_of(
  58                 dev->platform_data,
  59                 struct mmci_card_event, mmc0_plat_data);
  60
  61
  62         return sprintf(buf, "%d\n", !mmci_card->mmc_inserted);
  63 }
  64
  65 static DEVICE_ATTR(mmc_inserted, S_IRUGO, gpio_show, NULL);
  66
  67 static void _mmci_callback(struct work_struct *ws)
  68 {
  69
  70         struct mmci_card_event *mmci_card = container_of(
  71                 ws,
  72                 struct mmci_card_event, workq);
  73
  74         mdelay(20);
  75
  76         mmci_card->mmc_inserted = !!gpio_get_value(U300_GPIO_PIN_MMC_CD);
  77
  78         input_report_switch(mmci_card->mmc_input, KEY_INSERT,
  79                             !mmci_card->mmc_inserted);
  80         input_sync(mmci_card->mmc_input);
  81
  82         pr_debug("MMC/SD card was %s\n",
  83                  mmci_card->mmc_inserted ? "removed" : "inserted");
  84
  85         enable_irq_on_gpio_pin(U300_GPIO_PIN_MMC_CD, !mmci_card->mmc_inserted);
  86 }
  87
  88 int __devinit mmc_init(struct amba_device *adev)
  89 {
  90         struct mmci_card_event *mmci_card;
  91         struct device *mmcsd_device = &adev->dev;
  92         struct pmx *pmx;
  93         int ret = 0;
  94
  95         mmci_card = kzalloc(sizeof(struct mmci_card_event), GFP_KERNEL);
  96         if (!mmci_card)
  97                 return -ENOMEM;
  98
  99         /*
 100          * Do not set ocr_mask or voltage translation function,
 101          * we have a regulator we can control instead.
 102          */
 103         /* Nominally 2.85V on our platform */
 104         mmci_card->mmc0_plat_data.status = mmc_status;
 105         mmci_card->mmc0_plat_data.gpio_wp = -1;
 106         mmci_card->mmc0_plat_data.gpio_cd = -1;
 107         mmci_card->mmc0_plat_data.capabilities = MMC_CAP_MMC_HIGHSPEED |
 108                 MMC_CAP_SD_HIGHSPEED | MMC_CAP_4_BIT_DATA;
 109
 110         mmcsd_device->platform_data = (void *) &mmci_card->mmc0_plat_data;
 111
 112         INIT_WORK(&mmci_card->workq, _mmci_callback);
 113
 114         ret = gpio_request(U300_GPIO_PIN_MMC_CD, "MMC card detection");
 115         if (ret) {
 116                 printk(KERN_CRIT "Could not allocate MMC card detection " \
 117                        "GPIO pin\n");
 118                 goto out;
 119         }
 120
 121         ret = gpio_direction_input(U300_GPIO_PIN_MMC_CD);
 122         if (ret) {
 123                 printk(KERN_CRIT "Invalid GPIO pin requested\n");
 124                 goto out;
 125         }
 126
 127         ret = sysfs_create_file(&mmcsd_device->kobj,
 128                                &dev_attr_mmc_inserted.attr);
 129         if (ret)
 130                 goto out;
 131
 132         mmci_card->mmc_input = input_allocate_device();
 133         if (!mmci_card->mmc_input) {
 134                 printk(KERN_CRIT "Could not allocate MMC input device\n");
 135                 return -ENOMEM;
 136         }
 137
 138         mmci_card->mmc_input->name = "MMC insert notification";
 139         mmci_card->mmc_input->id.bustype = BUS_HOST;
 140         mmci_card->mmc_input->id.vendor = 0;
 141         mmci_card->mmc_input->id.product = 0;
 142         mmci_card->mmc_input->id.version = 0x0100;
 143         mmci_card->mmc_input->dev.parent = mmcsd_device;
 144         input_set_capability(mmci_card->mmc_input, EV_SW, KEY_INSERT);
 145
 146         /*
 147          * Since this must always be compiled into the kernel, this input
 148          * is never unregistered or free:ed.
 149          */
 150         ret = input_register_device(mmci_card->mmc_input);
 151         if (ret) {
 152                 input_free_device(mmci_card->mmc_input);
 153                 goto out;
 154         }
 155
 156         input_set_drvdata(mmci_card->mmc_input, mmci_card);
 157
 158         /*
 159          * Setup padmuxing for MMC. Since this must always be
 160          * compiled into the kernel, pmx is never released.
 161          */
 162         pmx = pmx_get(mmcsd_device, U300_APP_PMX_MMC_SETTING);
 163
 164         if (IS_ERR(pmx))
 165                 pr_warning("Could not get padmux handle\n");
 166         else {
 167                 ret = pmx_activate(mmcsd_device, pmx);
 168                 if (IS_ERR_VALUE(ret))
 169                         pr_warning("Could not activate padmuxing\n");
 170         }
 171
 172         ret = gpio_register_callback(U300_GPIO_PIN_MMC_CD, mmci_callback,
 173                                      mmci_card);
 174
 175         schedule_work(&mmci_card->workq);
 176
 177         printk(KERN_INFO "Registered MMC insert/remove notification\n");
 178 out:
 179         return ret;
 180 }