[S390] pm: ccw bus power management callbacks

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

6 files changed, 308 insertions, 60 deletions

diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c
index dc98b2c63862..30f516111307 100644
--- a/drivers/s390/cio/cmf.c
+++ b/drivers/s390/cio/cmf.c
@@ -1204,6 +1204,11 @@ static ssize_t cmb_enable_store(struct device *dev,
 
 DEVICE_ATTR(cmb_enable, 0644, cmb_enable_show, cmb_enable_store);
 
+int ccw_set_cmf(struct ccw_device *cdev, int enable)
+{
+        return cmbops->set(cdev, enable ? 2 : 0);
+}
+
 /**
  * enable_cmf() - switch on the channel measurement for a specific device
  *  @cdev:      The ccw device to be enabled
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 35441fa16be1..228a6c314d84 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -1895,6 +1895,242 @@ static void ccw_device_shutdown(struct device *dev)
         disable_cmf(cdev);
 }
 
+static int ccw_device_pm_prepare(struct device *dev)
+{
+        struct ccw_device *cdev = to_ccwdev(dev);
+
+        if (work_pending(&cdev->private->kick_work))
+                return -EAGAIN;
+        /* Fail while device is being set online/offline. */
+        if (atomic_read(&cdev->private->onoff))
+                return -EAGAIN;
+
+        if (cdev->online && cdev->drv && cdev->drv->prepare)
+                return cdev->drv->prepare(cdev);
+
+        return 0;
+}
+
+static void ccw_device_pm_complete(struct device *dev)
+{
+        struct ccw_device *cdev = to_ccwdev(dev);
+
+        if (cdev->online && cdev->drv && cdev->drv->complete)
+                cdev->drv->complete(cdev);
+}
+
+static int ccw_device_pm_freeze(struct device *dev)
+{
+        struct ccw_device *cdev = to_ccwdev(dev);
+        struct subchannel *sch = to_subchannel(cdev->dev.parent);
+        int ret, cm_enabled;
+
+        /* Fail suspend while device is in transistional state. */
+        if (!dev_fsm_final_state(cdev))
+                return -EAGAIN;
+        if (!cdev->online)
+                return 0;
+        if (cdev->drv && cdev->drv->freeze) {
+                ret = cdev->drv->freeze(cdev);
+                if (ret)
+                        return ret;
+        }
+
+        spin_lock_irq(sch->lock);
+        cm_enabled = cdev->private->cmb != NULL;
+        spin_unlock_irq(sch->lock);
+        if (cm_enabled) {
+                /* Don't have the css write on memory. */
+                ret = ccw_set_cmf(cdev, 0);
+                if (ret)
+                        return ret;
+        }
+        /* From here on, disallow device driver I/O. */
+        spin_lock_irq(sch->lock);
+        ret = cio_disable_subchannel(sch);
+        spin_unlock_irq(sch->lock);
+
+        return ret;
+}
+
+static int ccw_device_pm_thaw(struct device *dev)
+{
+        struct ccw_device *cdev = to_ccwdev(dev);
+        struct subchannel *sch = to_subchannel(cdev->dev.parent);
+        int ret, cm_enabled;
+
+        if (!cdev->online)
+                return 0;
+
+        spin_lock_irq(sch->lock);
+        /* Allow device driver I/O again. */
+        ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
+        cm_enabled = cdev->private->cmb != NULL;
+        spin_unlock_irq(sch->lock);
+        if (ret)
+                return ret;
+
+        if (cm_enabled) {
+                ret = ccw_set_cmf(cdev, 1);
+                if (ret)
+                        return ret;
+        }
+
+        if (cdev->drv && cdev->drv->thaw)
+                ret = cdev->drv->thaw(cdev);
+
+        return ret;
+}
+
+static void __ccw_device_pm_restore(struct ccw_device *cdev)
+{
+        struct subchannel *sch = to_subchannel(cdev->dev.parent);
+        int ret;
+
+        if (cio_is_console(sch->schid))
+                goto out;
+        /*
+         * While we were sleeping, devices may have gone or become
+         * available again. Kick re-detection.
+         */
+        spin_lock_irq(sch->lock);
+        cdev->private->flags.resuming = 1;
+        ret = ccw_device_recognition(cdev);
+        spin_unlock_irq(sch->lock);
+        if (ret) {
+                CIO_MSG_EVENT(0, "Couldn't start recognition for device "
+                              "%s (ret=%d)\n", dev_name(&cdev->dev), ret);
+                spin_lock_irq(sch->lock);
+                cdev->private->state = DEV_STATE_DISCONNECTED;
+                spin_unlock_irq(sch->lock);
+                /* notify driver after the resume cb */
+                goto out;
+        }
+        wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
+                   cdev->private->state == DEV_STATE_DISCONNECTED);
+
+out:
+        cdev->private->flags.resuming = 0;
+}
+
+static int resume_handle_boxed(struct ccw_device *cdev)
+{
+        cdev->private->state = DEV_STATE_BOXED;
+        if (ccw_device_notify(cdev, CIO_BOXED))
+                return 0;
+        ccw_device_schedule_sch_unregister(cdev);
+        return -ENODEV;
+}
+
+static int resume_handle_disc(struct ccw_device *cdev)
+{
+        cdev->private->state = DEV_STATE_DISCONNECTED;
+        if (ccw_device_notify(cdev, CIO_GONE))
+                return 0;
+        ccw_device_schedule_sch_unregister(cdev);
+        return -ENODEV;
+}
+
+static int ccw_device_pm_restore(struct device *dev)
+{
+        struct ccw_device *cdev = to_ccwdev(dev);
+        struct subchannel *sch = to_subchannel(cdev->dev.parent);
+        int ret = 0, cm_enabled;
+
+        __ccw_device_pm_restore(cdev);
+        spin_lock_irq(sch->lock);
+        if (cio_is_console(sch->schid)) {
+                cio_enable_subchannel(sch, (u32)(addr_t)sch);
+                spin_unlock_irq(sch->lock);
+                goto out_restore;
+        }
+        cdev->private->flags.donotify = 0;
+        /* check recognition results */
+        switch (cdev->private->state) {
+        case DEV_STATE_OFFLINE:
+                break;
+        case DEV_STATE_BOXED:
+                ret = resume_handle_boxed(cdev);
+                spin_unlock_irq(sch->lock);
+                if (ret)
+                        goto out;
+                goto out_restore;
+        case DEV_STATE_DISCONNECTED:
+                goto out_disc_unlock;
+        default:
+                goto out_unreg_unlock;
+        }
+        /* check if the device id has changed */
+        if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
+                CIO_MSG_EVENT(0, "resume: sch %s: failed (devno changed from "
+                              "%04x to %04x)\n", dev_name(&sch->dev),
+                              cdev->private->dev_id.devno,
+                              sch->schib.pmcw.dev);
+                goto out_unreg_unlock;
+        }
+        /* check if the device type has changed */
+        if (!ccw_device_test_sense_data(cdev)) {
+                ccw_device_update_sense_data(cdev);
+                PREPARE_WORK(&cdev->private->kick_work,
+                             ccw_device_do_unbind_bind);
+                queue_work(ccw_device_work, &cdev->private->kick_work);
+                ret = -ENODEV;
+                goto out_unlock;
+        }
+        if (!cdev->online) {
+                ret = 0;
+                goto out_unlock;
+        }
+        ret = ccw_device_online(cdev);
+        if (ret)
+                goto out_disc_unlock;
+
+        cm_enabled = cdev->private->cmb != NULL;
+        spin_unlock_irq(sch->lock);
+
+        wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
+        if (cdev->private->state != DEV_STATE_ONLINE) {
+                spin_lock_irq(sch->lock);
+                goto out_disc_unlock;
+        }
+        if (cm_enabled) {
+                ret = ccw_set_cmf(cdev, 1);
+                if (ret) {
+                        CIO_MSG_EVENT(2, "resume: cdev %s: cmf failed "
+                                      "(rc=%d)\n", dev_name(&cdev->dev), ret);
+                        ret = 0;
+                }
+        }
+
+out_restore:
+        if (cdev->online && cdev->drv && cdev->drv->restore)
+                ret = cdev->drv->restore(cdev);
+out:
+        return ret;
+
+out_disc_unlock:
+        ret = resume_handle_disc(cdev);
+        spin_unlock_irq(sch->lock);
+        if (ret)
+                return ret;
+        goto out_restore;
+
+out_unreg_unlock:
+        ccw_device_schedule_sch_unregister(cdev);
+        ret = -ENODEV;
+out_unlock:
+        spin_unlock_irq(sch->lock);
+        return ret;
+}
+
+static struct dev_pm_ops ccw_pm_ops = {
+        .prepare = ccw_device_pm_prepare,
+        .complete = ccw_device_pm_complete,
+        .freeze = ccw_device_pm_freeze,
+        .thaw = ccw_device_pm_thaw,
+        .restore = ccw_device_pm_restore,
+};
+
 struct bus_type ccw_bus_type = {
         .name   = "ccw",
         .match  = ccw_bus_match,
@@ -1902,6 +2138,7 @@ struct bus_type ccw_bus_type = {
         .probe  = ccw_device_probe,
         .remove = ccw_device_remove,
         .shutdown = ccw_device_shutdown,
+        .pm = &ccw_pm_ops,
 };
 
 /**
diff --git a/drivers/s390/cio/device.h b/drivers/s390/cio/device.h
index f1cbbd94ad4e..e3975107a578 100644
--- a/drivers/s390/cio/device.h
+++ b/drivers/s390/cio/device.h
@@ -87,6 +87,8 @@ int ccw_device_is_orphan(struct ccw_device *);
 int ccw_device_recognition(struct ccw_device *);
 int ccw_device_online(struct ccw_device *);
 int ccw_device_offline(struct ccw_device *);
+void ccw_device_update_sense_data(struct ccw_device *);
+int ccw_device_test_sense_data(struct ccw_device *);
 void ccw_device_schedule_sch_unregister(struct ccw_device *);
 int ccw_purge_blacklisted(void);
 
@@ -133,5 +135,6 @@ extern struct bus_type ccw_bus_type;
 void retry_set_schib(struct ccw_device *cdev);
 void cmf_retry_copy_block(struct ccw_device *);
 int cmf_reenable(struct ccw_device *);
+int ccw_set_cmf(struct ccw_device *cdev, int enable);
 extern struct device_attribute dev_attr_cmb_enable;
 #endif
diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index e46049261561..3db88c52d287 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -177,29 +177,21 @@ ccw_device_cancel_halt_clear(struct ccw_device *cdev)
         panic("Can't stop i/o on subchannel.\n");
 }
 
-static int
-ccw_device_handle_oper(struct ccw_device *cdev)
+void ccw_device_update_sense_data(struct ccw_device *cdev)
 {
-        struct subchannel *sch;
+        memset(&cdev->id, 0, sizeof(cdev->id));
+        cdev->id.cu_type   = cdev->private->senseid.cu_type;
+        cdev->id.cu_model  = cdev->private->senseid.cu_model;
+        cdev->id.dev_type  = cdev->private->senseid.dev_type;
+        cdev->id.dev_model = cdev->private->senseid.dev_model;
+}
 
-        sch = to_subchannel(cdev->dev.parent);
-        cdev->private->flags.recog_done = 1;
-        /*
-         * Check if cu type and device type still match. If
-         * not, it is certainly another device and we have to
-         * de- and re-register.
-         */
-        if (cdev->id.cu_type != cdev->private->senseid.cu_type ||
-            cdev->id.cu_model != cdev->private->senseid.cu_model ||
-            cdev->id.dev_type != cdev->private->senseid.dev_type ||
-            cdev->id.dev_model != cdev->private->senseid.dev_model) {
-                PREPARE_WORK(&cdev->private->kick_work,
-                             ccw_device_do_unbind_bind);
-                queue_work(ccw_device_work, &cdev->private->kick_work);
-                return 0;
-        }
-        cdev->private->flags.donotify = 1;
-        return 1;
+int ccw_device_test_sense_data(struct ccw_device *cdev)
+{
+        return cdev->id.cu_type == cdev->private->senseid.cu_type &&
+                cdev->id.cu_model == cdev->private->senseid.cu_model &&
+                cdev->id.dev_type == cdev->private->senseid.dev_type &&
+                cdev->id.dev_model == cdev->private->senseid.dev_model;
 }
 
 /*
@@ -233,7 +225,7 @@ static void
 ccw_device_recog_done(struct ccw_device *cdev, int state)
 {
         struct subchannel *sch;
-        int notify, old_lpm, same_dev;
+        int old_lpm;
 
         sch = to_subchannel(cdev->dev.parent);
 
@@ -263,8 +255,12 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
                 wake_up(&cdev->private->wait_q);
                 return;
         }
-        notify = 0;
-        same_dev = 0; /* Keep the compiler quiet... */
+        if (cdev->private->flags.resuming) {
+                cdev->private->state = state;
+                cdev->private->flags.recog_done = 1;
+                wake_up(&cdev->private->wait_q);
+                return;
+        }
         switch (state) {
         case DEV_STATE_NOT_OPER:
                 CIO_MSG_EVENT(2, "SenseID : unknown device %04x on "
@@ -273,34 +269,31 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
                               sch->schid.ssid, sch->schid.sch_no);
                 break;
         case DEV_STATE_OFFLINE:
-                if (cdev->online) {
-                        same_dev = ccw_device_handle_oper(cdev);
-                        notify = 1;
+                if (!cdev->online) {
+                        ccw_device_update_sense_data(cdev);
+                        /* Issue device info message. */
+                        CIO_MSG_EVENT(4, "SenseID : device 0.%x.%04x reports: "
+                                      "CU  Type/Mod = %04X/%02X, Dev Type/Mod "
+                                      "= %04X/%02X\n",
+                                      cdev->private->dev_id.ssid,
+                                      cdev->private->dev_id.devno,
+                                      cdev->id.cu_type, cdev->id.cu_model,
+                                      cdev->id.dev_type, cdev->id.dev_model);
+                        break;
                 }
-                /* fill out sense information */
-                memset(&cdev->id, 0, sizeof(cdev->id));
-                cdev->id.cu_type   = cdev->private->senseid.cu_type;
-                cdev->id.cu_model  = cdev->private->senseid.cu_model;
-                cdev->id.dev_type  = cdev->private->senseid.dev_type;
-                cdev->id.dev_model = cdev->private->senseid.dev_model;
-                if (notify) {
-                        cdev->private->state = DEV_STATE_OFFLINE;
-                        if (same_dev) {
-                                /* Get device online again. */
-                                ccw_device_online(cdev);
-                                wake_up(&cdev->private->wait_q);
-                        }
-                        return;
+                cdev->private->state = DEV_STATE_OFFLINE;
+                cdev->private->flags.recog_done = 1;
+                if (ccw_device_test_sense_data(cdev)) {
+                        cdev->private->flags.donotify = 1;
+                        ccw_device_online(cdev);
+                        wake_up(&cdev->private->wait_q);
+                } else {
+                        ccw_device_update_sense_data(cdev);
+                        PREPARE_WORK(&cdev->private->kick_work,
+                                     ccw_device_do_unbind_bind);
+                        queue_work(ccw_device_work, &cdev->private->kick_work);
                 }
-                /* Issue device info message. */
-                CIO_MSG_EVENT(4, "SenseID : device 0.%x.%04x reports: "
-                              "CU  Type/Mod = %04X/%02X, Dev Type/Mod = "
-                              "%04X/%02X\n",
-                              cdev->private->dev_id.ssid,
-                              cdev->private->dev_id.devno,
-                              cdev->id.cu_type, cdev->id.cu_model,
-                              cdev->id.dev_type, cdev->id.dev_model);
-                break;
+                return;
         case DEV_STATE_BOXED:
                 CIO_MSG_EVENT(0, "SenseID : boxed device %04x on "
                               " subchannel 0.%x.%04x\n",
@@ -502,9 +495,6 @@ ccw_device_recognition(struct ccw_device *cdev)
         struct subchannel *sch;
         int ret;
 
-        if ((cdev->private->state != DEV_STATE_NOT_OPER) &&
-            (cdev->private->state != DEV_STATE_BOXED))
-                return -EINVAL;
         sch = to_subchannel(cdev->dev.parent);
         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
         if (ret != 0)
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index bf0a24af39a0..2d0efee8a290 100644
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -1,10 +1,8 @@
 /*
- *  drivers/s390/cio/device_ops.c
+ * Copyright IBM Corp. 2002, 2009
  *
- *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
- *                       IBM Corporation
- *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
- *               Cornelia Huck (cornelia.huck@de.ibm.com)
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *            Cornelia Huck (cornelia.huck@de.ibm.com)
  */
 #include <linux/module.h>
 #include <linux/init.h>
@@ -116,12 +114,15 @@ int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
 
         if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
+        sch = to_subchannel(cdev->dev.parent);
+        if (!sch->schib.pmcw.ena)
+                return -EINVAL;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
         if (cdev->private->state != DEV_STATE_ONLINE &&
             cdev->private->state != DEV_STATE_W4SENSE)
                 return -EINVAL;
-        sch = to_subchannel(cdev->dev.parent);
+
         ret = cio_clear(sch);
         if (ret == 0)
                 cdev->private->intparm = intparm;
@@ -162,6 +163,8 @@ int ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
         if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
         sch = to_subchannel(cdev->dev.parent);
+        if (!sch->schib.pmcw.ena)
+                return -EINVAL;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
         if (cdev->private->state == DEV_STATE_VERIFY ||
@@ -337,12 +340,15 @@ int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
 
         if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
+        sch = to_subchannel(cdev->dev.parent);
+        if (!sch->schib.pmcw.ena)
+                return -EINVAL;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
         if (cdev->private->state != DEV_STATE_ONLINE &&
             cdev->private->state != DEV_STATE_W4SENSE)
                 return -EINVAL;
-        sch = to_subchannel(cdev->dev.parent);
+
         ret = cio_halt(sch);
         if (ret == 0)
                 cdev->private->intparm = intparm;
@@ -369,6 +375,8 @@ int ccw_device_resume(struct ccw_device *cdev)
         if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
         sch = to_subchannel(cdev->dev.parent);
+        if (!sch->schib.pmcw.ena)
+                return -EINVAL;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
         if (cdev->private->state != DEV_STATE_ONLINE ||
@@ -580,6 +588,8 @@ int ccw_device_tm_start_key(struct ccw_device *cdev, struct tcw *tcw,
         int rc;
 
         sch = to_subchannel(cdev->dev.parent);
+        if (!sch->schib.pmcw.ena)
+                return -EINVAL;
         if (cdev->private->state != DEV_STATE_ONLINE)
                 return -EIO;
         /* Adjust requested path mask to excluded varied off paths. */
@@ -669,6 +679,8 @@ int ccw_device_tm_intrg(struct ccw_device *cdev)
 {
         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 
+        if (!sch->schib.pmcw.ena)
+                return -EINVAL;
         if (cdev->private->state != DEV_STATE_ONLINE)
                 return -EIO;
         if (!scsw_is_tm(&sch->schib.scsw) ||
diff --git a/drivers/s390/cio/io_sch.h b/drivers/s390/cio/io_sch.h
index c4f3e7c9a854..0b8f381bd20e 100644
--- a/drivers/s390/cio/io_sch.h
+++ b/drivers/s390/cio/io_sch.h
@@ -107,6 +107,7 @@ struct ccw_device_private {
                 unsigned int recog_done:1;  /* dev. recog. complete */
                 unsigned int fake_irb:1;    /* deliver faked irb */
                 unsigned int intretry:1;    /* retry internal operation */
+                unsigned int resuming:1;    /* recognition while resume */
         } __attribute__((packed)) flags;
         unsigned long intparm;  /* user interruption parameter */
         struct qdio_irq *qdio_data;