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 static bool odd_can_poweroff(struct ata_device *ata_dev)
  89 {
  90         acpi_handle handle;
  91         struct acpi_device *acpi_dev;
  92
  93         handle = ata_dev_acpi_handle(ata_dev);
  94         if (!handle)
  95                 return false;
  96
  97         if (acpi_bus_get_device(handle, &acpi_dev))
  98                 return false;
  99
 100         return acpi_device_can_poweroff(acpi_dev);
 101 }
 102
 103 /* Test if ODD is zero power ready by sense code */
 104 static bool zpready(struct ata_device *dev)
 105 {
 106         u8 sense_key, *sense_buf;
 107         unsigned int ret, asc, ascq, add_len;
 108         struct zpodd *zpodd = dev->zpodd;
 109
 110         ret = atapi_eh_tur(dev, &sense_key);
 111
 112         if (!ret || sense_key != NOT_READY)
 113                 return false;
 114
 115         sense_buf = dev->link->ap->sector_buf;
 116         ret = atapi_eh_request_sense(dev, sense_buf, sense_key);
 117         if (ret)
 118                 return false;
 119
 120         /* sense valid */
 121         if ((sense_buf[0] & 0x7f) != 0x70)
 122                 return false;
 123
 124         add_len = sense_buf[7];
 125         /* has asc and ascq */
 126         if (add_len < 6)
 127                 return false;
 128
 129         asc = sense_buf[12];
 130         ascq = sense_buf[13];
 131
 132         if (zpodd->mech_type == ODD_MECH_TYPE_SLOT)
 133                 /* no media inside */
 134                 return asc == 0x3a;
 135         else
 136                 /* no media inside and door closed */
 137                 return asc == 0x3a && ascq == 0x01;
 138 }
 139
 140 /*
 141  * Update the zpodd->zp_ready field. This field will only be set
 142  * if the ODD has stayed in ZP ready state for zpodd_poweroff_delay
 143  * time, and will be used to decide if power off is allowed. If it
 144  * is set, it will be cleared during resume from powered off state.
 145  */
 146 void zpodd_on_suspend(struct ata_device *dev)
 147 {
 148         struct zpodd *zpodd = dev->zpodd;
 149         unsigned long expires;
 150
 151         if (!zpready(dev)) {
 152                 zpodd->zp_sampled = false;
 153                 zpodd->zp_ready = false;
 154                 return;
 155         }
 156
 157         if (!zpodd->zp_sampled) {
 158                 zpodd->zp_sampled = true;
 159                 zpodd->last_ready = jiffies;
 160                 return;
 161         }
 162
 163         expires = zpodd->last_ready +
 164                   msecs_to_jiffies(zpodd_poweroff_delay * 1000);
 165         if (time_before(jiffies, expires))
 166                 return;
 167
 168         zpodd->zp_ready = true;
 169 }
 170
 171 bool zpodd_zpready(struct ata_device *dev)
 172 {
 173         struct zpodd *zpodd = dev->zpodd;
 174         return zpodd->zp_ready;
 175 }
 176
 177 /*
 178  * Enable runtime wake capability through ACPI and set the powered_off flag,
 179  * this flag will be used during resume to decide what operations are needed
 180  * to take.
 181  *
 182  * Also, media poll needs to be silenced, so that it doesn't bring the ODD
 183  * back to full power state every few seconds.
 184  */
 185 void zpodd_enable_run_wake(struct ata_device *dev)
 186 {
 187         struct zpodd *zpodd = dev->zpodd;
 188
 189         sdev_disable_disk_events(dev->sdev);
 190
 191         zpodd->powered_off = true;
 192         device_set_run_wake(&dev->tdev, true);
 193         acpi_pm_device_run_wake(&dev->tdev, true);
 194 }
 195
 196 /* Disable runtime wake capability if it is enabled */
 197 void zpodd_disable_run_wake(struct ata_device *dev)
 198 {
 199         struct zpodd *zpodd = dev->zpodd;
 200
 201         if (zpodd->powered_off) {
 202                 acpi_pm_device_run_wake(&dev->tdev, false);
 203                 device_set_run_wake(&dev->tdev, false);
 204         }
 205 }
 206
 207 /*
 208  * Post power on processing after the ODD has been recovered. If the
 209  * ODD wasn't powered off during suspend, it doesn't do anything.
 210  *
 211  * For drawer type ODD, if it is powered on due to user pressed the
 212  * eject button, the tray needs to be ejected. This can only be done
 213  * after the ODD has been recovered, i.e. link is initialized and
 214  * device is able to process NON_DATA PIO command, as eject needs to
 215  * send command for the ODD to process.
 216  *
 217  * The from_notify flag set in wake notification handler function
 218  * zpodd_wake_dev represents if power on is due to user's action.
 219  *
 220  * For both types of ODD, several fields need to be reset.
 221  */
 222 void zpodd_post_poweron(struct ata_device *dev)
 223 {
 224         struct zpodd *zpodd = dev->zpodd;
 225
 226         if (!zpodd->powered_off)
 227                 return;
 228
 229         zpodd->powered_off = false;
 230
 231         if (zpodd->from_notify) {
 232                 zpodd->from_notify = false;
 233                 if (zpodd->mech_type == ODD_MECH_TYPE_DRAWER)
 234                         eject_tray(dev);
 235         }
 236
 237         zpodd->zp_sampled = false;
 238         zpodd->zp_ready = false;
 239
 240         sdev_enable_disk_events(dev->sdev);
 241 }
 242
 243 static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context)
 244 {
 245         struct ata_device *ata_dev = context;
 246         struct zpodd *zpodd = ata_dev->zpodd;
 247         struct device *dev = &ata_dev->sdev->sdev_gendev;
 248
 249         if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) {
 250                 zpodd->from_notify = true;
 251                 pm_runtime_resume(dev);
 252         }
 253 }
 254
 255 static void ata_acpi_add_pm_notifier(struct ata_device *dev)
 256 {
 257         acpi_handle handle = ata_dev_acpi_handle(dev);
 258         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
 259                                     zpodd_wake_dev, dev);
 260 }
 261
 262 static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
 263 {
 264         acpi_handle handle = ata_dev_acpi_handle(dev);
 265         acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, zpodd_wake_dev);
 266 }
 267
 268 void zpodd_init(struct ata_device *dev)
 269 {
 270         enum odd_mech_type mech_type;
 271         struct zpodd *zpodd;
 272
 273         if (dev->zpodd)
 274                 return;
 275
 276         if (!odd_can_poweroff(dev))
 277                 return;
 278
 279         mech_type = zpodd_get_mech_type(dev);
 280         if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
 281                 return;
 282
 283         zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
 284         if (!zpodd)
 285                 return;
 286
 287         zpodd->mech_type = mech_type;
 288
 289         ata_acpi_add_pm_notifier(dev);
 290         zpodd->dev = dev;
 291         dev->zpodd = zpodd;
 292         dev_pm_qos_expose_flags(&dev->tdev, 0);
 293 }
 294
 295 void zpodd_exit(struct ata_device *dev)
 296 {
 297         ata_acpi_remove_pm_notifier(dev);
 298         kfree(dev->zpodd);
 299         dev->zpodd = NULL;
 300 }