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 #include <linux/slab.h>
  24
  25 #include "mmc.h"
  26 #include "padmux.h"
  27
  28 struct mmci_card_event {
  29         struct input_dev *mmc_input;
  30         int mmc_inserted;
  31         struct work_struct workq;
  32         struct mmci_platform_data mmc0_plat_data;
  33 };
  34
  35 static unsigned int mmc_status(struct device *dev)
  36 {
  37         struct mmci_card_event *mmci_card = container_of(
  38                 dev->platform_data,
  39                 struct mmci_card_event, mmc0_plat_data);
  40
  41         return mmci_card->mmc_inserted;
  42 }
  43
  44 static int mmci_callback(void *data)
  45 {
  46         struct mmci_card_event *mmci_card = data;
  47
  48         disable_irq_on_gpio_pin(U300_GPIO_PIN_MMC_CD);
  49         schedule_work(&mmci_card->workq);
  50
  51         return 0;
  52 }
  53
  54
  55 static ssize_t gpio_show(struct device *dev, struct device_attribute *attr,
  56                   char *buf)
  57 {
  58         struct mmci_card_event *mmci_card = container_of(
  59                 dev->platform_data,
  60                 struct mmci_card_event, mmc0_plat_data);
  61
  62
  63         return sprintf(buf, "%d\n", !mmci_card->mmc_inserted);
  64 }
  65
  66 static DEVICE_ATTR(mmc_inserted, S_IRUGO, gpio_show, NULL);
  67
  68 static void _mmci_callback(struct work_struct *ws)
  69 {
  70
  71         struct mmci_card_event *mmci_card = container_of(
  72                 ws,
  73                 struct mmci_card_event, workq);
  74
  75         mdelay(20);
  76
  77         mmci_card->mmc_inserted = !!gpio_get_value(U300_GPIO_PIN_MMC_CD);
  78
  79         input_report_switch(mmci_card->mmc_input, KEY_INSERT,
  80                             !mmci_card->mmc_inserted);
  81         input_sync(mmci_card->mmc_input);
  82
  83         pr_debug("MMC/SD card was %s\n",
  84                  mmci_card->mmc_inserted ? "removed" : "inserted");
  85
  86         enable_irq_on_gpio_pin(U300_GPIO_PIN_MMC_CD, !mmci_card->mmc_inserted);
  87 }
  88
  89 int __devinit mmc_init(struct amba_device *adev)
  90 {
  91         struct mmci_card_event *mmci_card;
  92         struct device *mmcsd_device = &adev->dev;
  93         struct pmx *pmx;
  94         int ret = 0;
  95
  96         mmci_card = kzalloc(sizeof(struct mmci_card_event), GFP_KERNEL);
  97         if (!mmci_card)
  98                 return -ENOMEM;
  99
 100         /*
 101          * Do not set ocr_mask or voltage translation function,
 102          * we have a regulator we can control instead.
 103          */
 104         /* Nominally 2.85V on our platform */
 105         mmci_card->mmc0_plat_data.f_max = 24000000;
 106         mmci_card->mmc0_plat_data.status = mmc_status;
 107         mmci_card->mmc0_plat_data.gpio_wp = -1;
 108         mmci_card->mmc0_plat_data.gpio_cd = -1;
 109         mmci_card->mmc0_plat_data.capabilities = MMC_CAP_MMC_HIGHSPEED |
 110                 MMC_CAP_SD_HIGHSPEED | MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
 111
 112         mmcsd_device->platform_data = (void *) &mmci_card->mmc0_plat_data;
 113
 114         INIT_WORK(&mmci_card->workq, _mmci_callback);
 115
 116         ret = gpio_request(U300_GPIO_PIN_MMC_CD, "MMC card detection");
 117         if (ret) {
 118                 printk(KERN_CRIT "Could not allocate MMC card detection " \
 119                        "GPIO pin\n");
 120                 goto out;
 121         }
 122
 123         ret = gpio_direction_input(U300_GPIO_PIN_MMC_CD);
 124         if (ret) {
 125                 printk(KERN_CRIT "Invalid GPIO pin requested\n");
 126                 goto out;
 127         }
 128
 129         ret = sysfs_create_file(&mmcsd_device->kobj,
 130                                &dev_attr_mmc_inserted.attr);
 131         if (ret)
 132                 goto out;
 133
 134         mmci_card->mmc_input = input_allocate_device();
 135         if (!mmci_card->mmc_input) {
 136                 printk(KERN_CRIT "Could not allocate MMC input device\n");
 137                 return -ENOMEM;
 138         }
 139
 140         mmci_card->mmc_input->name = "MMC insert notification";
 141         mmci_card->mmc_input->id.bustype = BUS_HOST;
 142         mmci_card->mmc_input->id.vendor = 0;
 143         mmci_card->mmc_input->id.product = 0;
 144         mmci_card->mmc_input->id.version = 0x0100;
 145         mmci_card->mmc_input->dev.parent = mmcsd_device;
 146         input_set_capability(mmci_card->mmc_input, EV_SW, KEY_INSERT);
 147
 148         /*
 149          * Since this must always be compiled into the kernel, this input
 150          * is never unregistered or free:ed.
 151          */
 152         ret = input_register_device(mmci_card->mmc_input);
 153         if (ret) {
 154                 input_free_device(mmci_card->mmc_input);
 155                 goto out;
 156         }
 157
 158         input_set_drvdata(mmci_card->mmc_input, mmci_card);
 159
 160         /*
 161          * Setup padmuxing for MMC. Since this must always be
 162          * compiled into the kernel, pmx is never released.
 163          */
 164         pmx = pmx_get(mmcsd_device, U300_APP_PMX_MMC_SETTING);
 165
 166         if (IS_ERR(pmx))
 167                 pr_warning("Could not get padmux handle\n");
 168         else {
 169                 ret = pmx_activate(mmcsd_device, pmx);
 170                 if (IS_ERR_VALUE(ret))
 171                         pr_warning("Could not activate padmuxing\n");
 172         }
 173
 174         ret = gpio_register_callback(U300_GPIO_PIN_MMC_CD, mmci_callback,
 175                                      mmci_card);
 176
 177         schedule_work(&mmci_card->workq);
 178
 179         printk(KERN_INFO "Registered MMC insert/remove notification\n");
 180 out:
 181         return ret;
 182 }