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
  23 #include <asm/mach/mmc.h>
  24 #include "mmc.h"
  25
  26 struct mmci_card_event {
  27         struct input_dev *mmc_input;
  28         int mmc_inserted;
  29         struct work_struct workq;
  30         struct mmc_platform_data mmc0_plat_data;
  31 };
  32
  33 static unsigned int mmc_status(struct device *dev)
  34 {
  35         struct mmci_card_event *mmci_card = container_of(
  36                 dev->platform_data,
  37                 struct mmci_card_event, mmc0_plat_data);
  38
  39         return mmci_card->mmc_inserted;
  40 }
  41
  42 /*
  43  * Here follows a large chunk of code which will only be enabled if you
  44  * have both the AB3100 chip mounted and the MMC subsystem activated.
  45  */
  46
  47 static u32 mmc_translate_vdd(struct device *dev, unsigned int voltage)
  48 {
  49         int v;
  50
  51         /*
  52          * MMC Spec:
  53          * bit 7:       1.70 - 1.95V
  54          * bit 8 - 14:  2.0 - 2.6V
  55          * bit 15 - 23: 2.7 - 3.6V
  56          *
  57          * ab3100 voltages:
  58          * 000 - 2.85V
  59          * 001 - 2.75V
  60          * 010 - 1.8V
  61          * 011 - 1.5V
  62          */
  63         switch (voltage) {
  64         case 8:
  65                 v = 3;
  66                 break;
  67         case 9:
  68         case 10:
  69         case 11:
  70         case 12:
  71         case 13:
  72         case 14:
  73         case 15:
  74                 v = 1;
  75                 break;
  76         case 16:
  77                 v = 1;
  78                 break;
  79         case 17:
  80         case 18:
  81         case 19:
  82         case 20:
  83         case 21:
  84         case 22:
  85         case 23:
  86         case 24:
  87                 v = 0;
  88                 break;
  89         default:
  90                 v = 0;
  91                 break;
  92         }
  93
  94         /* PL180 voltage register bits */
  95         return v << 2;
  96 }
  97
  98
  99
 100 static int mmci_callback(void *data)
 101 {
 102         struct mmci_card_event *mmci_card = data;
 103
 104         disable_irq_on_gpio_pin(U300_GPIO_PIN_MMC_CD);
 105         schedule_work(&mmci_card->workq);
 106
 107         return 0;
 108 }
 109
 110
 111 static ssize_t gpio_show(struct device *dev, struct device_attribute *attr,
 112                   char *buf)
 113 {
 114         struct mmci_card_event *mmci_card = container_of(
 115                 dev->platform_data,
 116                 struct mmci_card_event, mmc0_plat_data);
 117
 118
 119         return sprintf(buf, "%d\n", !mmci_card->mmc_inserted);
 120 }
 121
 122 static DEVICE_ATTR(mmc_inserted, S_IRUGO, gpio_show, NULL);
 123
 124 static void _mmci_callback(struct work_struct *ws)
 125 {
 126
 127         struct mmci_card_event *mmci_card = container_of(
 128                 ws,
 129                 struct mmci_card_event, workq);
 130
 131         mdelay(20);
 132
 133         mmci_card->mmc_inserted = !!gpio_get_value(U300_GPIO_PIN_MMC_CD);
 134
 135         input_report_switch(mmci_card->mmc_input, KEY_INSERT,
 136                             !mmci_card->mmc_inserted);
 137         input_sync(mmci_card->mmc_input);
 138
 139         pr_debug("MMC/SD card was %s\n",
 140                  mmci_card->mmc_inserted ? "removed" : "inserted");
 141
 142         enable_irq_on_gpio_pin(U300_GPIO_PIN_MMC_CD, !mmci_card->mmc_inserted);
 143 }
 144
 145 int __devinit mmc_init(struct amba_device *adev)
 146 {
 147         struct mmci_card_event *mmci_card;
 148         struct device *mmcsd_device = &adev->dev;
 149         int ret = 0;
 150
 151         mmci_card = kzalloc(sizeof(struct mmci_card_event), GFP_KERNEL);
 152         if (!mmci_card)
 153                 return -ENOMEM;
 154
 155         /* Nominally 2.85V on our platform */
 156         mmci_card->mmc0_plat_data.ocr_mask = MMC_VDD_28_29;
 157         mmci_card->mmc0_plat_data.translate_vdd = mmc_translate_vdd;
 158         mmci_card->mmc0_plat_data.status = mmc_status;
 159         mmci_card->mmc0_plat_data.gpio_wp = -1;
 160         mmci_card->mmc0_plat_data.gpio_cd = -1;
 161
 162         mmcsd_device->platform_data = (void *) &mmci_card->mmc0_plat_data;
 163
 164         INIT_WORK(&mmci_card->workq, _mmci_callback);
 165
 166         ret = gpio_request(U300_GPIO_PIN_MMC_CD, "MMC card detection");
 167         if (ret) {
 168                 printk(KERN_CRIT "Could not allocate MMC card detection " \
 169                        "GPIO pin\n");
 170                 goto out;
 171         }
 172
 173         ret = gpio_direction_input(U300_GPIO_PIN_MMC_CD);
 174         if (ret) {
 175                 printk(KERN_CRIT "Invalid GPIO pin requested\n");
 176                 goto out;
 177         }
 178
 179         ret = sysfs_create_file(&mmcsd_device->kobj,
 180                                &dev_attr_mmc_inserted.attr);
 181         if (ret)
 182                 goto out;
 183
 184         mmci_card->mmc_input = input_allocate_device();
 185         if (!mmci_card->mmc_input) {
 186                 printk(KERN_CRIT "Could not allocate MMC input device\n");
 187                 return -ENOMEM;
 188         }
 189
 190         mmci_card->mmc_input->name = "MMC insert notification";
 191         mmci_card->mmc_input->id.bustype = BUS_HOST;
 192         mmci_card->mmc_input->id.vendor = 0;
 193         mmci_card->mmc_input->id.product = 0;
 194         mmci_card->mmc_input->id.version = 0x0100;
 195         mmci_card->mmc_input->dev.parent = mmcsd_device;
 196         input_set_capability(mmci_card->mmc_input, EV_SW, KEY_INSERT);
 197
 198         /*
 199          * Since this must always be compiled into the kernel, this input
 200          * is never unregistered or free:ed.
 201          */
 202         ret = input_register_device(mmci_card->mmc_input);
 203         if (ret) {
 204                 input_free_device(mmci_card->mmc_input);
 205                 goto out;
 206         }
 207
 208         input_set_drvdata(mmci_card->mmc_input, mmci_card);
 209
 210         ret = gpio_register_callback(U300_GPIO_PIN_MMC_CD, mmci_callback,
 211                                      mmci_card);
 212
 213         schedule_work(&mmci_card->workq);
 214
 215         printk(KERN_INFO "Registered MMC insert/remove notification\n");
 216 out:
 217         return ret;
 218 }