drivers/ata/libata-zpodd.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/libata.h>
   3 #include <linux/cdrom.h>
   4 #include <linux/pm_runtime.h>
   5 #include <linux/module.h>
   6 #include <linux/pm_qos.h>
   7 #include <scsi/scsi_device.h>
   8
   9 #include "libata.h"
  10
  11 static int zpodd_poweroff_delay = 30; /* 30 seconds for power off delay */
  12 module_param(zpodd_poweroff_delay, int, 0644);
  13 MODULE_PARM_DESC(zpodd_poweroff_delay, "Poweroff delay for ZPODD in seconds");
  14
  15 enum odd_mech_type {
  16         ODD_MECH_TYPE_SLOT,
  17         ODD_MECH_TYPE_DRAWER,
  18         ODD_MECH_TYPE_UNSUPPORTED,
  19 };
  20
  21 struct zpodd {
  22         enum odd_mech_type      mech_type; /* init during probe, RO afterwards */
  23         struct ata_device       *dev;
  24
  25         /* The following fields are synchronized by PM core. */
  26         bool                    from_notify; /* resumed as a result of
  27                                               * acpi wake notification */
  28         bool                    zp_ready; /* ZP ready state */
  29         unsigned long           last_ready; /* last ZP ready timestamp */
  30         bool                    zp_sampled; /* ZP ready state sampled */
  31         bool                    powered_off; /* ODD is powered off
  32                                               * during suspend */
  33 };
  34
  35 static int eject_tray(struct ata_device *dev)
  36 {
  37         struct ata_taskfile tf;
  38         static const char cdb[ATAPI_CDB_LEN] = {  GPCMD_START_STOP_UNIT,
  39                 0, 0, 0,
  40                 0x02,     /* LoEj */
  41                 0, 0, 0, 0, 0, 0, 0,
  42         };
  43
  44         ata_tf_init(dev, &tf);
  45         tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
  46         tf.command = ATA_CMD_PACKET;
  47         tf.protocol = ATAPI_PROT_NODATA;
  48
  49         return ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
  50 }
  51
  52 /* Per the spec, only slot type and drawer type ODD can be supported */
  53 static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
  54 {
  55         char *buf;
  56         unsigned int ret;
  57         struct rm_feature_desc *desc;
  58         struct ata_taskfile tf;
  59         static const char cdb[ATAPI_CDB_LEN] = {  GPCMD_GET_CONFIGURATION,
  60                         2,      /* only 1 feature descriptor requested */
  61                         0, 3,   /* 3, removable medium feature */
  62                         0, 0, 0,/* reserved */
  63                         0, 16,
  64                         0, 0, 0,
  65         };
  66
  67         buf = kzalloc(16, GFP_KERNEL);
  68         if (!buf)
  69                 return ODD_MECH_TYPE_UNSUPPORTED;
  70         desc = (void *)(buf + 8);
  71
  72         ata_tf_init(dev, &tf);
  73         tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
  74         tf.command = ATA_CMD_PACKET;
  75         tf.protocol = ATAPI_PROT_PIO;
  76         tf.lbam = 16;
  77
  78         ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
  79                                 buf, 16, 0);
  80         if (ret) {
  81                 kfree(buf);
  82                 return ODD_MECH_TYPE_UNSUPPORTED;
  83         }
  84
  85         if (be16_to_cpu(desc->feature_code) != 3) {
  86                 kfree(buf);
  87                 return ODD_MECH_TYPE_UNSUPPORTED;
  88         }
  89
  90         if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1) {
  91                 kfree(buf);
  92                 return ODD_MECH_TYPE_SLOT;
  93         } else if (desc->mech_type == 1 && desc->load == 0 &&
  94                    desc->eject == 1) {
  95                 kfree(buf);
  96                 return ODD_MECH_TYPE_DRAWER;
  97         } else {
  98                 kfree(buf);
  99                 return ODD_MECH_TYPE_UNSUPPORTED;
 100         }
 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         acpi_pm_set_device_wakeup(&dev->tdev, true);
 193 }
 194
 195 /* Disable runtime wake capability if it is enabled */
 196 void zpodd_disable_run_wake(struct ata_device *dev)
 197 {
 198         struct zpodd *zpodd = dev->zpodd;
 199
 200         if (zpodd->powered_off)
 201                 acpi_pm_set_device_wakeup(&dev->tdev, false);
 202 }
 203
 204 /*
 205  * Post power on processing after the ODD has been recovered. If the
 206  * ODD wasn't powered off during suspend, it doesn't do anything.
 207  *
 208  * For drawer type ODD, if it is powered on due to user pressed the
 209  * eject button, the tray needs to be ejected. This can only be done
 210  * after the ODD has been recovered, i.e. link is initialized and
 211  * device is able to process NON_DATA PIO command, as eject needs to
 212  * send command for the ODD to process.
 213  *
 214  * The from_notify flag set in wake notification handler function
 215  * zpodd_wake_dev represents if power on is due to user's action.
 216  *
 217  * For both types of ODD, several fields need to be reset.
 218  */
 219 void zpodd_post_poweron(struct ata_device *dev)
 220 {
 221         struct zpodd *zpodd = dev->zpodd;
 222
 223         if (!zpodd->powered_off)
 224                 return;
 225
 226         zpodd->powered_off = false;
 227
 228         if (zpodd->from_notify) {
 229                 zpodd->from_notify = false;
 230                 if (zpodd->mech_type == ODD_MECH_TYPE_DRAWER)
 231                         eject_tray(dev);
 232         }
 233
 234         zpodd->zp_sampled = false;
 235         zpodd->zp_ready = false;
 236
 237         sdev_enable_disk_events(dev->sdev);
 238 }
 239
 240 static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context)
 241 {
 242         struct ata_device *ata_dev = context;
 243         struct zpodd *zpodd = ata_dev->zpodd;
 244         struct device *dev = &ata_dev->sdev->sdev_gendev;
 245
 246         if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) {
 247                 zpodd->from_notify = true;
 248                 pm_runtime_resume(dev);
 249         }
 250 }
 251
 252 static void ata_acpi_add_pm_notifier(struct ata_device *dev)
 253 {
 254         acpi_handle handle = ata_dev_acpi_handle(dev);
 255         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
 256                                     zpodd_wake_dev, dev);
 257 }
 258
 259 static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
 260 {
 261         acpi_handle handle = ata_dev_acpi_handle(dev);
 262         acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, zpodd_wake_dev);
 263 }
 264
 265 void zpodd_init(struct ata_device *dev)
 266 {
 267         struct acpi_device *adev = ACPI_COMPANION(&dev->tdev);
 268         enum odd_mech_type mech_type;
 269         struct zpodd *zpodd;
 270
 271         if (dev->zpodd || !adev || !acpi_device_can_poweroff(adev))
 272                 return;
 273
 274         mech_type = zpodd_get_mech_type(dev);
 275         if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
 276                 return;
 277
 278         zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
 279         if (!zpodd)
 280                 return;
 281
 282         zpodd->mech_type = mech_type;
 283
 284         ata_acpi_add_pm_notifier(dev);
 285         zpodd->dev = dev;
 286         dev->zpodd = zpodd;
 287         dev_pm_qos_expose_flags(&dev->tdev, 0);
 288 }
 289
 290 void zpodd_exit(struct ata_device *dev)
 291 {
 292         ata_acpi_remove_pm_notifier(dev);
 293         kfree(dev->zpodd);
 294         dev->zpodd = NULL;
 295 }