drivers/ata/libata-zpodd.c

   1 #include <linux/libata.h>
   2 #include <linux/cdrom.h>
   3 #include <linux/pm_runtime.h>
   4 #include <linux/module.h>
   5 #include <linux/pm_qos.h>
   6 #include <scsi/scsi_device.h>
   7
   8 #include "libata.h"
   9
  10 static int zpodd_poweroff_delay = 30; /* 30 seconds for power off delay */
  11 module_param(zpodd_poweroff_delay, int, 0644);
  12 MODULE_PARM_DESC(zpodd_poweroff_delay, "Poweroff delay for ZPODD in seconds");
  13
  14 enum odd_mech_type {
  15         ODD_MECH_TYPE_SLOT,
  16         ODD_MECH_TYPE_DRAWER,
  17         ODD_MECH_TYPE_UNSUPPORTED,
  18 };
  19
  20 struct zpodd {
  21         enum odd_mech_type      mech_type; /* init during probe, RO afterwards */
  22         struct ata_device       *dev;
  23
  24         /* The following fields are synchronized by PM core. */
  25         bool                    from_notify; /* resumed as a result of
  26                                               * acpi wake notification */
  27         bool                    zp_ready; /* ZP ready state */
  28         unsigned long           last_ready; /* last ZP ready timestamp */
  29         bool                    zp_sampled; /* ZP ready state sampled */
  30         bool                    powered_off; /* ODD is powered off
  31                                               * during suspend */
  32 };
  33
  34 static int eject_tray(struct ata_device *dev)
  35 {
  36         struct ata_taskfile tf;
  37         const char cdb[] = {  GPCMD_START_STOP_UNIT,
  38                 0, 0, 0,
  39                 0x02,     /* LoEj */
  40                 0, 0, 0, 0, 0, 0, 0,
  41         };
  42
  43         ata_tf_init(dev, &tf);
  44         tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
  45         tf.command = ATA_CMD_PACKET;
  46         tf.protocol = ATAPI_PROT_NODATA;
  47
  48         return ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
  49 }
  50
  51 /* Per the spec, only slot type and drawer type ODD can be supported */
  52 static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
  53 {
  54         char buf[16];
  55         unsigned int ret;
  56         struct rm_feature_desc *desc = (void *)(buf + 8);
  57         struct ata_taskfile tf;
  58         char cdb[] = {  GPCMD_GET_CONFIGURATION,
  59                         2,      /* only 1 feature descriptor requested */
  60                         0, 3,   /* 3, removable medium feature */
  61                         0, 0, 0,/* reserved */
  62                         0, sizeof(buf),
  63                         0, 0, 0,
  64         };
  65
  66         ata_tf_init(dev, &tf);
  67         tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
  68         tf.command = ATA_CMD_PACKET;
  69         tf.protocol = ATAPI_PROT_PIO;
  70         tf.lbam = sizeof(buf);
  71
  72         ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
  73                                 buf, sizeof(buf), 0);
  74         if (ret)
  75                 return ODD_MECH_TYPE_UNSUPPORTED;
  76
  77         if (be16_to_cpu(desc->feature_code) != 3)
  78                 return ODD_MECH_TYPE_UNSUPPORTED;
  79
  80         if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1)
  81                 return ODD_MECH_TYPE_SLOT;
  82         else if (desc->mech_type == 1 && desc->load == 0 && desc->eject == 1)
  83                 return ODD_MECH_TYPE_DRAWER;
  84         else
  85                 return ODD_MECH_TYPE_UNSUPPORTED;
  86 }
  87
  88 /* Test if ODD is zero power ready by sense code */
  89 static bool zpready(struct ata_device *dev)
  90 {
  91         u8 sense_key, *sense_buf;
  92         unsigned int ret, asc, ascq, add_len;
  93         struct zpodd *zpodd = dev->zpodd;
  94
  95         ret = atapi_eh_tur(dev, &sense_key);
  96
  97         if (!ret || sense_key != NOT_READY)
  98                 return false;
  99
 100         sense_buf = dev->link->ap->sector_buf;
 101         ret = atapi_eh_request_sense(dev, sense_buf, sense_key);
 102         if (ret)
 103                 return false;
 104
 105         /* sense valid */
 106         if ((sense_buf[0] & 0x7f) != 0x70)
 107                 return false;
 108
 109         add_len = sense_buf[7];
 110         /* has asc and ascq */
 111         if (add_len < 6)
 112                 return false;
 113
 114         asc = sense_buf[12];
 115         ascq = sense_buf[13];
 116
 117         if (zpodd->mech_type == ODD_MECH_TYPE_SLOT)
 118                 /* no media inside */
 119                 return asc == 0x3a;
 120         else
 121                 /* no media inside and door closed */
 122                 return asc == 0x3a && ascq == 0x01;
 123 }
 124
 125 /*
 126  * Update the zpodd->zp_ready field. This field will only be set
 127  * if the ODD has stayed in ZP ready state for zpodd_poweroff_delay
 128  * time, and will be used to decide if power off is allowed. If it
 129  * is set, it will be cleared during resume from powered off state.
 130  */
 131 void zpodd_on_suspend(struct ata_device *dev)
 132 {
 133         struct zpodd *zpodd = dev->zpodd;
 134         unsigned long expires;
 135
 136         if (!zpready(dev)) {
 137                 zpodd->zp_sampled = false;
 138                 zpodd->zp_ready = false;
 139                 return;
 140         }
 141
 142         if (!zpodd->zp_sampled) {
 143                 zpodd->zp_sampled = true;
 144                 zpodd->last_ready = jiffies;
 145                 return;
 146         }
 147
 148         expires = zpodd->last_ready +
 149                   msecs_to_jiffies(zpodd_poweroff_delay * 1000);
 150         if (time_before(jiffies, expires))
 151                 return;
 152
 153         zpodd->zp_ready = true;
 154 }
 155
 156 bool zpodd_zpready(struct ata_device *dev)
 157 {
 158         struct zpodd *zpodd = dev->zpodd;
 159         return zpodd->zp_ready;
 160 }
 161
 162 /*
 163  * Enable runtime wake capability through ACPI and set the powered_off flag,
 164  * this flag will be used during resume to decide what operations are needed
 165  * to take.
 166  *
 167  * Also, media poll needs to be silenced, so that it doesn't bring the ODD
 168  * back to full power state every few seconds.
 169  */
 170 void zpodd_enable_run_wake(struct ata_device *dev)
 171 {
 172         struct zpodd *zpodd = dev->zpodd;
 173
 174         sdev_disable_disk_events(dev->sdev);
 175
 176         zpodd->powered_off = true;
 177         acpi_pm_set_device_wakeup(&dev->tdev, true);
 178 }
 179
 180 /* Disable runtime wake capability if it is enabled */
 181 void zpodd_disable_run_wake(struct ata_device *dev)
 182 {
 183         struct zpodd *zpodd = dev->zpodd;
 184
 185         if (zpodd->powered_off)
 186                 acpi_pm_set_device_wakeup(&dev->tdev, false);
 187 }
 188
 189 /*
 190  * Post power on processing after the ODD has been recovered. If the
 191  * ODD wasn't powered off during suspend, it doesn't do anything.
 192  *
 193  * For drawer type ODD, if it is powered on due to user pressed the
 194  * eject button, the tray needs to be ejected. This can only be done
 195  * after the ODD has been recovered, i.e. link is initialized and
 196  * device is able to process NON_DATA PIO command, as eject needs to
 197  * send command for the ODD to process.
 198  *
 199  * The from_notify flag set in wake notification handler function
 200  * zpodd_wake_dev represents if power on is due to user's action.
 201  *
 202  * For both types of ODD, several fields need to be reset.
 203  */
 204 void zpodd_post_poweron(struct ata_device *dev)
 205 {
 206         struct zpodd *zpodd = dev->zpodd;
 207
 208         if (!zpodd->powered_off)
 209                 return;
 210
 211         zpodd->powered_off = false;
 212
 213         if (zpodd->from_notify) {
 214                 zpodd->from_notify = false;
 215                 if (zpodd->mech_type == ODD_MECH_TYPE_DRAWER)
 216                         eject_tray(dev);
 217         }
 218
 219         zpodd->zp_sampled = false;
 220         zpodd->zp_ready = false;
 221
 222         sdev_enable_disk_events(dev->sdev);
 223 }
 224
 225 static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context)
 226 {
 227         struct ata_device *ata_dev = context;
 228         struct zpodd *zpodd = ata_dev->zpodd;
 229         struct device *dev = &ata_dev->sdev->sdev_gendev;
 230
 231         if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) {
 232                 zpodd->from_notify = true;
 233                 pm_runtime_resume(dev);
 234         }
 235 }
 236
 237 static void ata_acpi_add_pm_notifier(struct ata_device *dev)
 238 {
 239         acpi_handle handle = ata_dev_acpi_handle(dev);
 240         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
 241                                     zpodd_wake_dev, dev);
 242 }
 243
 244 static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
 245 {
 246         acpi_handle handle = ata_dev_acpi_handle(dev);
 247         acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, zpodd_wake_dev);
 248 }
 249
 250 void zpodd_init(struct ata_device *dev)
 251 {
 252         struct acpi_device *adev = ACPI_COMPANION(&dev->tdev);
 253         enum odd_mech_type mech_type;
 254         struct zpodd *zpodd;
 255
 256         if (dev->zpodd || !adev || !acpi_device_can_poweroff(adev))
 257                 return;
 258
 259         mech_type = zpodd_get_mech_type(dev);
 260         if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
 261                 return;
 262
 263         zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
 264         if (!zpodd)
 265                 return;
 266
 267         zpodd->mech_type = mech_type;
 268
 269         ata_acpi_add_pm_notifier(dev);
 270         zpodd->dev = dev;
 271         dev->zpodd = zpodd;
 272         dev_pm_qos_expose_flags(&dev->tdev, 0);
 273 }
 274
 275 void zpodd_exit(struct ata_device *dev)
 276 {
 277         ata_acpi_remove_pm_notifier(dev);
 278         kfree(dev->zpodd);
 279         dev->zpodd = NULL;
 280 }