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[16];
  56         unsigned int ret;
  57         struct rm_feature_desc *desc = (void *)(buf + 8);
  58         struct ata_taskfile tf;
  59         static const char cdb[] = {  GPCMD_GET_CONFIGURATION,
  60                         2,      /* only 1 feature descriptor requested */
  61                         0, 3,   /* 3, removable medium feature */
  62                         0, 0, 0,/* reserved */
  63                         0, sizeof(buf),
  64                         0, 0, 0,
  65         };
  66
  67         ata_tf_init(dev, &tf);
  68         tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
  69         tf.command = ATA_CMD_PACKET;
  70         tf.protocol = ATAPI_PROT_PIO;
  71         tf.lbam = sizeof(buf);
  72
  73         ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
  74                                 buf, sizeof(buf), 0);
  75         if (ret)
  76                 return ODD_MECH_TYPE_UNSUPPORTED;
  77
  78         if (be16_to_cpu(desc->feature_code) != 3)
  79                 return ODD_MECH_TYPE_UNSUPPORTED;
  80
  81         if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1)
  82                 return ODD_MECH_TYPE_SLOT;
  83         else if (desc->mech_type == 1 && desc->load == 0 && desc->eject == 1)
  84                 return ODD_MECH_TYPE_DRAWER;
  85         else
  86                 return ODD_MECH_TYPE_UNSUPPORTED;
  87 }
  88
  89 /* Test if ODD is zero power ready by sense code */
  90 static bool zpready(struct ata_device *dev)
  91 {
  92         u8 sense_key, *sense_buf;
  93         unsigned int ret, asc, ascq, add_len;
  94         struct zpodd *zpodd = dev->zpodd;
  95
  96         ret = atapi_eh_tur(dev, &sense_key);
  97
  98         if (!ret || sense_key != NOT_READY)
  99                 return false;
 100
 101         sense_buf = dev->link->ap->sector_buf;
 102         ret = atapi_eh_request_sense(dev, sense_buf, sense_key);
 103         if (ret)
 104                 return false;
 105
 106         /* sense valid */
 107         if ((sense_buf[0] & 0x7f) != 0x70)
 108                 return false;
 109
 110         add_len = sense_buf[7];
 111         /* has asc and ascq */
 112         if (add_len < 6)
 113                 return false;
 114
 115         asc = sense_buf[12];
 116         ascq = sense_buf[13];
 117
 118         if (zpodd->mech_type == ODD_MECH_TYPE_SLOT)
 119                 /* no media inside */
 120                 return asc == 0x3a;
 121         else
 122                 /* no media inside and door closed */
 123                 return asc == 0x3a && ascq == 0x01;
 124 }
 125
 126 /*
 127  * Update the zpodd->zp_ready field. This field will only be set
 128  * if the ODD has stayed in ZP ready state for zpodd_poweroff_delay
 129  * time, and will be used to decide if power off is allowed. If it
 130  * is set, it will be cleared during resume from powered off state.
 131  */
 132 void zpodd_on_suspend(struct ata_device *dev)
 133 {
 134         struct zpodd *zpodd = dev->zpodd;
 135         unsigned long expires;
 136
 137         if (!zpready(dev)) {
 138                 zpodd->zp_sampled = false;
 139                 zpodd->zp_ready = false;
 140                 return;
 141         }
 142
 143         if (!zpodd->zp_sampled) {
 144                 zpodd->zp_sampled = true;
 145                 zpodd->last_ready = jiffies;
 146                 return;
 147         }
 148
 149         expires = zpodd->last_ready +
 150                   msecs_to_jiffies(zpodd_poweroff_delay * 1000);
 151         if (time_before(jiffies, expires))
 152                 return;
 153
 154         zpodd->zp_ready = true;
 155 }
 156
 157 bool zpodd_zpready(struct ata_device *dev)
 158 {
 159         struct zpodd *zpodd = dev->zpodd;
 160         return zpodd->zp_ready;
 161 }
 162
 163 /*
 164  * Enable runtime wake capability through ACPI and set the powered_off flag,
 165  * this flag will be used during resume to decide what operations are needed
 166  * to take.
 167  *
 168  * Also, media poll needs to be silenced, so that it doesn't bring the ODD
 169  * back to full power state every few seconds.
 170  */
 171 void zpodd_enable_run_wake(struct ata_device *dev)
 172 {
 173         struct zpodd *zpodd = dev->zpodd;
 174
 175         sdev_disable_disk_events(dev->sdev);
 176
 177         zpodd->powered_off = true;
 178         acpi_pm_set_device_wakeup(&dev->tdev, true);
 179 }
 180
 181 /* Disable runtime wake capability if it is enabled */
 182 void zpodd_disable_run_wake(struct ata_device *dev)
 183 {
 184         struct zpodd *zpodd = dev->zpodd;
 185
 186         if (zpodd->powered_off)
 187                 acpi_pm_set_device_wakeup(&dev->tdev, false);
 188 }
 189
 190 /*
 191  * Post power on processing after the ODD has been recovered. If the
 192  * ODD wasn't powered off during suspend, it doesn't do anything.
 193  *
 194  * For drawer type ODD, if it is powered on due to user pressed the
 195  * eject button, the tray needs to be ejected. This can only be done
 196  * after the ODD has been recovered, i.e. link is initialized and
 197  * device is able to process NON_DATA PIO command, as eject needs to
 198  * send command for the ODD to process.
 199  *
 200  * The from_notify flag set in wake notification handler function
 201  * zpodd_wake_dev represents if power on is due to user's action.
 202  *
 203  * For both types of ODD, several fields need to be reset.
 204  */
 205 void zpodd_post_poweron(struct ata_device *dev)
 206 {
 207         struct zpodd *zpodd = dev->zpodd;
 208
 209         if (!zpodd->powered_off)
 210                 return;
 211
 212         zpodd->powered_off = false;
 213
 214         if (zpodd->from_notify) {
 215                 zpodd->from_notify = false;
 216                 if (zpodd->mech_type == ODD_MECH_TYPE_DRAWER)
 217                         eject_tray(dev);
 218         }
 219
 220         zpodd->zp_sampled = false;
 221         zpodd->zp_ready = false;
 222
 223         sdev_enable_disk_events(dev->sdev);
 224 }
 225
 226 static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context)
 227 {
 228         struct ata_device *ata_dev = context;
 229         struct zpodd *zpodd = ata_dev->zpodd;
 230         struct device *dev = &ata_dev->sdev->sdev_gendev;
 231
 232         if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) {
 233                 zpodd->from_notify = true;
 234                 pm_runtime_resume(dev);
 235         }
 236 }
 237
 238 static void ata_acpi_add_pm_notifier(struct ata_device *dev)
 239 {
 240         acpi_handle handle = ata_dev_acpi_handle(dev);
 241         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
 242                                     zpodd_wake_dev, dev);
 243 }
 244
 245 static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
 246 {
 247         acpi_handle handle = ata_dev_acpi_handle(dev);
 248         acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, zpodd_wake_dev);
 249 }
 250
 251 void zpodd_init(struct ata_device *dev)
 252 {
 253         struct acpi_device *adev = ACPI_COMPANION(&dev->tdev);
 254         enum odd_mech_type mech_type;
 255         struct zpodd *zpodd;
 256
 257         if (dev->zpodd || !adev || !acpi_device_can_poweroff(adev))
 258                 return;
 259
 260         mech_type = zpodd_get_mech_type(dev);
 261         if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
 262                 return;
 263
 264         zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
 265         if (!zpodd)
 266                 return;
 267
 268         zpodd->mech_type = mech_type;
 269
 270         ata_acpi_add_pm_notifier(dev);
 271         zpodd->dev = dev;
 272         dev->zpodd = zpodd;
 273         dev_pm_qos_expose_flags(&dev->tdev, 0);
 274 }
 275
 276 void zpodd_exit(struct ata_device *dev)
 277 {
 278         ata_acpi_remove_pm_notifier(dev);
 279         kfree(dev->zpodd);
 280         dev->zpodd = NULL;
 281 }