summaryrefslogtreecommitdiff
path: root/drivers/s390/cio/device.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/s390/cio/device.c')
-rw-r--r--drivers/s390/cio/device.c1135
1 files changed, 1135 insertions, 0 deletions
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
new file mode 100644
index 000000000000..df0325505e4e
--- /dev/null
+++ b/drivers/s390/cio/device.c
@@ -0,0 +1,1135 @@
+/*
+ * drivers/s390/cio/device.c
+ * bus driver for ccw devices
+ * $Revision: 1.131 $
+ *
+ * Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
+ * IBM Corporation
+ * Author(s): Arnd Bergmann (arndb@de.ibm.com)
+ * Cornelia Huck (cohuck@de.ibm.com)
+ * Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/device.h>
+#include <linux/workqueue.h>
+
+#include <asm/ccwdev.h>
+#include <asm/cio.h>
+
+#include "cio.h"
+#include "css.h"
+#include "device.h"
+#include "ioasm.h"
+
+/******************* bus type handling ***********************/
+
+/* The Linux driver model distinguishes between a bus type and
+ * the bus itself. Of course we only have one channel
+ * subsystem driver and one channel system per machine, but
+ * we still use the abstraction. T.R. says it's a good idea. */
+static int
+ccw_bus_match (struct device * dev, struct device_driver * drv)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct ccw_driver *cdrv = to_ccwdrv(drv);
+ const struct ccw_device_id *ids = cdrv->ids, *found;
+
+ if (!ids)
+ return 0;
+
+ found = ccw_device_id_match(ids, &cdev->id);
+ if (!found)
+ return 0;
+
+ cdev->id.driver_info = found->driver_info;
+
+ return 1;
+}
+
+/*
+ * Hotplugging interface for ccw devices.
+ * Heavily modeled on pci and usb hotplug.
+ */
+static int
+ccw_hotplug (struct device *dev, char **envp, int num_envp,
+ char *buffer, int buffer_size)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ int i = 0;
+ int length = 0;
+
+ if (!cdev)
+ return -ENODEV;
+
+ /* what we want to pass to /sbin/hotplug */
+
+ envp[i++] = buffer;
+ length += scnprintf(buffer, buffer_size - length, "CU_TYPE=%04X",
+ cdev->id.cu_type);
+ if ((buffer_size - length <= 0) || (i >= num_envp))
+ return -ENOMEM;
+ ++length;
+ buffer += length;
+
+ envp[i++] = buffer;
+ length += scnprintf(buffer, buffer_size - length, "CU_MODEL=%02X",
+ cdev->id.cu_model);
+ if ((buffer_size - length <= 0) || (i >= num_envp))
+ return -ENOMEM;
+ ++length;
+ buffer += length;
+
+ /* The next two can be zero, that's ok for us */
+ envp[i++] = buffer;
+ length += scnprintf(buffer, buffer_size - length, "DEV_TYPE=%04X",
+ cdev->id.dev_type);
+ if ((buffer_size - length <= 0) || (i >= num_envp))
+ return -ENOMEM;
+ ++length;
+ buffer += length;
+
+ envp[i++] = buffer;
+ length += scnprintf(buffer, buffer_size - length, "DEV_MODEL=%02X",
+ cdev->id.dev_model);
+ if ((buffer_size - length <= 0) || (i >= num_envp))
+ return -ENOMEM;
+
+ envp[i] = 0;
+
+ return 0;
+}
+
+struct bus_type ccw_bus_type = {
+ .name = "ccw",
+ .match = &ccw_bus_match,
+ .hotplug = &ccw_hotplug,
+};
+
+static int io_subchannel_probe (struct device *);
+static int io_subchannel_remove (struct device *);
+void io_subchannel_irq (struct device *);
+static int io_subchannel_notify(struct device *, int);
+static void io_subchannel_verify(struct device *);
+static void io_subchannel_ioterm(struct device *);
+static void io_subchannel_shutdown(struct device *);
+
+struct css_driver io_subchannel_driver = {
+ .subchannel_type = SUBCHANNEL_TYPE_IO,
+ .drv = {
+ .name = "io_subchannel",
+ .bus = &css_bus_type,
+ .probe = &io_subchannel_probe,
+ .remove = &io_subchannel_remove,
+ .shutdown = &io_subchannel_shutdown,
+ },
+ .irq = io_subchannel_irq,
+ .notify = io_subchannel_notify,
+ .verify = io_subchannel_verify,
+ .termination = io_subchannel_ioterm,
+};
+
+struct workqueue_struct *ccw_device_work;
+struct workqueue_struct *ccw_device_notify_work;
+static wait_queue_head_t ccw_device_init_wq;
+static atomic_t ccw_device_init_count;
+
+static int __init
+init_ccw_bus_type (void)
+{
+ int ret;
+
+ init_waitqueue_head(&ccw_device_init_wq);
+ atomic_set(&ccw_device_init_count, 0);
+
+ ccw_device_work = create_singlethread_workqueue("cio");
+ if (!ccw_device_work)
+ return -ENOMEM; /* FIXME: better errno ? */
+ ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
+ if (!ccw_device_notify_work) {
+ ret = -ENOMEM; /* FIXME: better errno ? */
+ goto out_err;
+ }
+ slow_path_wq = create_singlethread_workqueue("kslowcrw");
+ if (!slow_path_wq) {
+ ret = -ENOMEM; /* FIXME: better errno ? */
+ goto out_err;
+ }
+ if ((ret = bus_register (&ccw_bus_type)))
+ goto out_err;
+
+ if ((ret = driver_register(&io_subchannel_driver.drv)))
+ goto out_err;
+
+ wait_event(ccw_device_init_wq,
+ atomic_read(&ccw_device_init_count) == 0);
+ flush_workqueue(ccw_device_work);
+ return 0;
+out_err:
+ if (ccw_device_work)
+ destroy_workqueue(ccw_device_work);
+ if (ccw_device_notify_work)
+ destroy_workqueue(ccw_device_notify_work);
+ if (slow_path_wq)
+ destroy_workqueue(slow_path_wq);
+ return ret;
+}
+
+static void __exit
+cleanup_ccw_bus_type (void)
+{
+ driver_unregister(&io_subchannel_driver.drv);
+ bus_unregister(&ccw_bus_type);
+ destroy_workqueue(ccw_device_notify_work);
+ destroy_workqueue(ccw_device_work);
+}
+
+subsys_initcall(init_ccw_bus_type);
+module_exit(cleanup_ccw_bus_type);
+
+/************************ device handling **************************/
+
+/*
+ * A ccw_device has some interfaces in sysfs in addition to the
+ * standard ones.
+ * The following entries are designed to export the information which
+ * resided in 2.4 in /proc/subchannels. Subchannel and device number
+ * are obvious, so they don't have an entry :)
+ * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
+ */
+static ssize_t
+chpids_show (struct device * dev, char * buf)
+{
+ struct subchannel *sch = to_subchannel(dev);
+ struct ssd_info *ssd = &sch->ssd_info;
+ ssize_t ret = 0;
+ int chp;
+
+ for (chp = 0; chp < 8; chp++)
+ ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
+
+ ret += sprintf (buf+ret, "\n");
+ return min((ssize_t)PAGE_SIZE, ret);
+}
+
+static ssize_t
+pimpampom_show (struct device * dev, char * buf)
+{
+ struct subchannel *sch = to_subchannel(dev);
+ struct pmcw *pmcw = &sch->schib.pmcw;
+
+ return sprintf (buf, "%02x %02x %02x\n",
+ pmcw->pim, pmcw->pam, pmcw->pom);
+}
+
+static ssize_t
+devtype_show (struct device *dev, char *buf)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct ccw_device_id *id = &(cdev->id);
+
+ if (id->dev_type != 0)
+ return sprintf(buf, "%04x/%02x\n",
+ id->dev_type, id->dev_model);
+ else
+ return sprintf(buf, "n/a\n");
+}
+
+static ssize_t
+cutype_show (struct device *dev, char *buf)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct ccw_device_id *id = &(cdev->id);
+
+ return sprintf(buf, "%04x/%02x\n",
+ id->cu_type, id->cu_model);
+}
+
+static ssize_t
+online_show (struct device *dev, char *buf)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+
+ return sprintf(buf, cdev->online ? "1\n" : "0\n");
+}
+
+static void
+ccw_device_remove_disconnected(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+ /*
+ * Forced offline in disconnected state means
+ * 'throw away device'.
+ */
+ sch = to_subchannel(cdev->dev.parent);
+ device_unregister(&sch->dev);
+ /* Reset intparm to zeroes. */
+ sch->schib.pmcw.intparm = 0;
+ cio_modify(sch);
+ put_device(&sch->dev);
+}
+
+int
+ccw_device_set_offline(struct ccw_device *cdev)
+{
+ int ret;
+
+ if (!cdev)
+ return -ENODEV;
+ if (!cdev->online || !cdev->drv)
+ return -EINVAL;
+
+ if (cdev->drv->set_offline) {
+ ret = cdev->drv->set_offline(cdev);
+ if (ret != 0)
+ return ret;
+ }
+ cdev->online = 0;
+ spin_lock_irq(cdev->ccwlock);
+ ret = ccw_device_offline(cdev);
+ if (ret == -ENODEV) {
+ if (cdev->private->state != DEV_STATE_NOT_OPER) {
+ cdev->private->state = DEV_STATE_OFFLINE;
+ dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
+ }
+ spin_unlock_irq(cdev->ccwlock);
+ return ret;
+ }
+ spin_unlock_irq(cdev->ccwlock);
+ if (ret == 0)
+ wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
+ else {
+ pr_debug("ccw_device_offline returned %d, device %s\n",
+ ret, cdev->dev.bus_id);
+ cdev->online = 1;
+ }
+ return ret;
+}
+
+int
+ccw_device_set_online(struct ccw_device *cdev)
+{
+ int ret;
+
+ if (!cdev)
+ return -ENODEV;
+ if (cdev->online || !cdev->drv)
+ return -EINVAL;
+
+ spin_lock_irq(cdev->ccwlock);
+ ret = ccw_device_online(cdev);
+ spin_unlock_irq(cdev->ccwlock);
+ if (ret == 0)
+ wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
+ else {
+ pr_debug("ccw_device_online returned %d, device %s\n",
+ ret, cdev->dev.bus_id);
+ return ret;
+ }
+ if (cdev->private->state != DEV_STATE_ONLINE)
+ return -ENODEV;
+ if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
+ cdev->online = 1;
+ return 0;
+ }
+ spin_lock_irq(cdev->ccwlock);
+ ret = ccw_device_offline(cdev);
+ spin_unlock_irq(cdev->ccwlock);
+ if (ret == 0)
+ wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
+ else
+ pr_debug("ccw_device_offline returned %d, device %s\n",
+ ret, cdev->dev.bus_id);
+ return (ret = 0) ? -ENODEV : ret;
+}
+
+static ssize_t
+online_store (struct device *dev, const char *buf, size_t count)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ int i, force, ret;
+ char *tmp;
+
+ if (atomic_compare_and_swap(0, 1, &cdev->private->onoff))
+ return -EAGAIN;
+
+ if (cdev->drv && !try_module_get(cdev->drv->owner)) {
+ atomic_set(&cdev->private->onoff, 0);
+ return -EINVAL;
+ }
+ if (!strncmp(buf, "force\n", count)) {
+ force = 1;
+ i = 1;
+ } else {
+ force = 0;
+ i = simple_strtoul(buf, &tmp, 16);
+ }
+ if (i == 1) {
+ /* Do device recognition, if needed. */
+ if (cdev->id.cu_type == 0) {
+ ret = ccw_device_recognition(cdev);
+ if (ret) {
+ printk(KERN_WARNING"Couldn't start recognition "
+ "for device %s (ret=%d)\n",
+ cdev->dev.bus_id, ret);
+ goto out;
+ }
+ wait_event(cdev->private->wait_q,
+ cdev->private->flags.recog_done);
+ }
+ if (cdev->drv && cdev->drv->set_online)
+ ccw_device_set_online(cdev);
+ } else if (i == 0) {
+ if (cdev->private->state == DEV_STATE_DISCONNECTED)
+ ccw_device_remove_disconnected(cdev);
+ else if (cdev->drv && cdev->drv->set_offline)
+ ccw_device_set_offline(cdev);
+ }
+ if (force && cdev->private->state == DEV_STATE_BOXED) {
+ ret = ccw_device_stlck(cdev);
+ if (ret) {
+ printk(KERN_WARNING"ccw_device_stlck for device %s "
+ "returned %d!\n", cdev->dev.bus_id, ret);
+ goto out;
+ }
+ /* Do device recognition, if needed. */
+ if (cdev->id.cu_type == 0) {
+ cdev->private->state = DEV_STATE_NOT_OPER;
+ ret = ccw_device_recognition(cdev);
+ if (ret) {
+ printk(KERN_WARNING"Couldn't start recognition "
+ "for device %s (ret=%d)\n",
+ cdev->dev.bus_id, ret);
+ goto out;
+ }
+ wait_event(cdev->private->wait_q,
+ cdev->private->flags.recog_done);
+ }
+ if (cdev->drv && cdev->drv->set_online)
+ ccw_device_set_online(cdev);
+ }
+ out:
+ if (cdev->drv)
+ module_put(cdev->drv->owner);
+ atomic_set(&cdev->private->onoff, 0);
+ return count;
+}
+
+static ssize_t
+available_show (struct device *dev, char *buf)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct subchannel *sch;
+
+ switch (cdev->private->state) {
+ case DEV_STATE_BOXED:
+ return sprintf(buf, "boxed\n");
+ case DEV_STATE_DISCONNECTED:
+ case DEV_STATE_DISCONNECTED_SENSE_ID:
+ case DEV_STATE_NOT_OPER:
+ sch = to_subchannel(dev->parent);
+ if (!sch->lpm)
+ return sprintf(buf, "no path\n");
+ else
+ return sprintf(buf, "no device\n");
+ default:
+ /* All other states considered fine. */
+ return sprintf(buf, "good\n");
+ }
+}
+
+static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
+static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
+static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
+static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
+static DEVICE_ATTR(online, 0644, online_show, online_store);
+extern struct device_attribute dev_attr_cmb_enable;
+static DEVICE_ATTR(availability, 0444, available_show, NULL);
+
+static struct attribute * subch_attrs[] = {
+ &dev_attr_chpids.attr,
+ &dev_attr_pimpampom.attr,
+ NULL,
+};
+
+static struct attribute_group subch_attr_group = {
+ .attrs = subch_attrs,
+};
+
+static inline int
+subchannel_add_files (struct device *dev)
+{
+ return sysfs_create_group(&dev->kobj, &subch_attr_group);
+}
+
+static struct attribute * ccwdev_attrs[] = {
+ &dev_attr_devtype.attr,
+ &dev_attr_cutype.attr,
+ &dev_attr_online.attr,
+ &dev_attr_cmb_enable.attr,
+ &dev_attr_availability.attr,
+ NULL,
+};
+
+static struct attribute_group ccwdev_attr_group = {
+ .attrs = ccwdev_attrs,
+};
+
+static inline int
+device_add_files (struct device *dev)
+{
+ return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
+}
+
+static inline void
+device_remove_files(struct device *dev)
+{
+ sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
+}
+
+/* this is a simple abstraction for device_register that sets the
+ * correct bus type and adds the bus specific files */
+int
+ccw_device_register(struct ccw_device *cdev)
+{
+ struct device *dev = &cdev->dev;
+ int ret;
+
+ dev->bus = &ccw_bus_type;
+
+ if ((ret = device_add(dev)))
+ return ret;
+
+ set_bit(1, &cdev->private->registered);
+ if ((ret = device_add_files(dev))) {
+ if (test_and_clear_bit(1, &cdev->private->registered))
+ device_del(dev);
+ }
+ return ret;
+}
+
+static struct ccw_device *
+get_disc_ccwdev_by_devno(unsigned int devno, struct ccw_device *sibling)
+{
+ struct ccw_device *cdev;
+ struct list_head *entry;
+ struct device *dev;
+
+ if (!get_bus(&ccw_bus_type))
+ return NULL;
+ down_read(&ccw_bus_type.subsys.rwsem);
+ cdev = NULL;
+ list_for_each(entry, &ccw_bus_type.devices.list) {
+ dev = get_device(container_of(entry,
+ struct device, bus_list));
+ if (!dev)
+ continue;
+ cdev = to_ccwdev(dev);
+ if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
+ (cdev->private->devno == devno) &&
+ (cdev != sibling)) {
+ cdev->private->state = DEV_STATE_NOT_OPER;
+ break;
+ }
+ put_device(dev);
+ cdev = NULL;
+ }
+ up_read(&ccw_bus_type.subsys.rwsem);
+ put_bus(&ccw_bus_type);
+
+ return cdev;
+}
+
+static void
+ccw_device_add_changed(void *data)
+{
+
+ struct ccw_device *cdev;
+
+ cdev = (struct ccw_device *)data;
+ if (device_add(&cdev->dev)) {
+ put_device(&cdev->dev);
+ return;
+ }
+ set_bit(1, &cdev->private->registered);
+ if (device_add_files(&cdev->dev)) {
+ if (test_and_clear_bit(1, &cdev->private->registered))
+ device_unregister(&cdev->dev);
+ }
+}
+
+extern int css_get_ssd_info(struct subchannel *sch);
+
+void
+ccw_device_do_unreg_rereg(void *data)
+{
+ struct ccw_device *cdev;
+ struct subchannel *sch;
+ int need_rename;
+
+ cdev = (struct ccw_device *)data;
+ sch = to_subchannel(cdev->dev.parent);
+ if (cdev->private->devno != sch->schib.pmcw.dev) {
+ /*
+ * The device number has changed. This is usually only when
+ * a device has been detached under VM and then re-appeared
+ * on another subchannel because of a different attachment
+ * order than before. Ideally, we should should just switch
+ * subchannels, but unfortunately, this is not possible with
+ * the current implementation.
+ * Instead, we search for the old subchannel for this device
+ * number and deregister so there are no collisions with the
+ * newly registered ccw_device.
+ * FIXME: Find another solution so the block layer doesn't
+ * get possibly sick...
+ */
+ struct ccw_device *other_cdev;
+
+ need_rename = 1;
+ other_cdev = get_disc_ccwdev_by_devno(sch->schib.pmcw.dev,
+ cdev);
+ if (other_cdev) {
+ struct subchannel *other_sch;
+
+ other_sch = to_subchannel(other_cdev->dev.parent);
+ if (get_device(&other_sch->dev)) {
+ stsch(other_sch->irq, &other_sch->schib);
+ if (other_sch->schib.pmcw.dnv) {
+ other_sch->schib.pmcw.intparm = 0;
+ cio_modify(other_sch);
+ }
+ device_unregister(&other_sch->dev);
+ }
+ }
+ /* Update ssd info here. */
+ css_get_ssd_info(sch);
+ cdev->private->devno = sch->schib.pmcw.dev;
+ } else
+ need_rename = 0;
+ device_remove_files(&cdev->dev);
+ if (test_and_clear_bit(1, &cdev->private->registered))
+ device_del(&cdev->dev);
+ if (need_rename)
+ snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
+ sch->schib.pmcw.dev);
+ PREPARE_WORK(&cdev->private->kick_work,
+ ccw_device_add_changed, (void *)cdev);
+ queue_work(ccw_device_work, &cdev->private->kick_work);
+}
+
+static void
+ccw_device_release(struct device *dev)
+{
+ struct ccw_device *cdev;
+
+ cdev = to_ccwdev(dev);
+ kfree(cdev->private);
+ kfree(cdev);
+}
+
+/*
+ * Register recognized device.
+ */
+static void
+io_subchannel_register(void *data)
+{
+ struct ccw_device *cdev;
+ struct subchannel *sch;
+ int ret;
+ unsigned long flags;
+
+ cdev = (struct ccw_device *) data;
+ sch = to_subchannel(cdev->dev.parent);
+
+ if (!list_empty(&sch->dev.children)) {
+ bus_rescan_devices(&ccw_bus_type);
+ goto out;
+ }
+ /* make it known to the system */
+ ret = ccw_device_register(cdev);
+ if (ret) {
+ printk (KERN_WARNING "%s: could not register %s\n",
+ __func__, cdev->dev.bus_id);
+ put_device(&cdev->dev);
+ spin_lock_irqsave(&sch->lock, flags);
+ sch->dev.driver_data = NULL;
+ spin_unlock_irqrestore(&sch->lock, flags);
+ kfree (cdev->private);
+ kfree (cdev);
+ put_device(&sch->dev);
+ if (atomic_dec_and_test(&ccw_device_init_count))
+ wake_up(&ccw_device_init_wq);
+ return;
+ }
+
+ ret = subchannel_add_files(cdev->dev.parent);
+ if (ret)
+ printk(KERN_WARNING "%s: could not add attributes to %s\n",
+ __func__, sch->dev.bus_id);
+ put_device(&cdev->dev);
+out:
+ cdev->private->flags.recog_done = 1;
+ put_device(&sch->dev);
+ wake_up(&cdev->private->wait_q);
+ if (atomic_dec_and_test(&ccw_device_init_count))
+ wake_up(&ccw_device_init_wq);
+}
+
+void
+ccw_device_call_sch_unregister(void *data)
+{
+ struct ccw_device *cdev = data;
+ struct subchannel *sch;
+
+ sch = to_subchannel(cdev->dev.parent);
+ device_unregister(&sch->dev);
+ /* Reset intparm to zeroes. */
+ sch->schib.pmcw.intparm = 0;
+ cio_modify(sch);
+ put_device(&cdev->dev);
+ put_device(&sch->dev);
+}
+
+/*
+ * subchannel recognition done. Called from the state machine.
+ */
+void
+io_subchannel_recog_done(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+
+ if (css_init_done == 0) {
+ cdev->private->flags.recog_done = 1;
+ return;
+ }
+ switch (cdev->private->state) {
+ case DEV_STATE_NOT_OPER:
+ cdev->private->flags.recog_done = 1;
+ /* Remove device found not operational. */
+ if (!get_device(&cdev->dev))
+ break;
+ sch = to_subchannel(cdev->dev.parent);
+ PREPARE_WORK(&cdev->private->kick_work,
+ ccw_device_call_sch_unregister, (void *) cdev);
+ queue_work(slow_path_wq, &cdev->private->kick_work);
+ if (atomic_dec_and_test(&ccw_device_init_count))
+ wake_up(&ccw_device_init_wq);
+ break;
+ case DEV_STATE_BOXED:
+ /* Device did not respond in time. */
+ case DEV_STATE_OFFLINE:
+ /*
+ * We can't register the device in interrupt context so
+ * we schedule a work item.
+ */
+ if (!get_device(&cdev->dev))
+ break;
+ PREPARE_WORK(&cdev->private->kick_work,
+ io_subchannel_register, (void *) cdev);
+ queue_work(slow_path_wq, &cdev->private->kick_work);
+ break;
+ }
+}
+
+static int
+io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
+{
+ int rc;
+ struct ccw_device_private *priv;
+
+ sch->dev.driver_data = cdev;
+ sch->driver = &io_subchannel_driver;
+ cdev->ccwlock = &sch->lock;
+ /* Init private data. */
+ priv = cdev->private;
+ priv->devno = sch->schib.pmcw.dev;
+ priv->irq = sch->irq;
+ priv->state = DEV_STATE_NOT_OPER;
+ INIT_LIST_HEAD(&priv->cmb_list);
+ init_waitqueue_head(&priv->wait_q);
+ init_timer(&priv->timer);
+
+ /* Set an initial name for the device. */
+ snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
+ sch->schib.pmcw.dev);
+
+ /* Increase counter of devices currently in recognition. */
+ atomic_inc(&ccw_device_init_count);
+
+ /* Start async. device sensing. */
+ spin_lock_irq(&sch->lock);
+ rc = ccw_device_recognition(cdev);
+ spin_unlock_irq(&sch->lock);
+ if (rc) {
+ if (atomic_dec_and_test(&ccw_device_init_count))
+ wake_up(&ccw_device_init_wq);
+ }
+ return rc;
+}
+
+static int
+io_subchannel_probe (struct device *pdev)
+{
+ struct subchannel *sch;
+ struct ccw_device *cdev;
+ int rc;
+ unsigned long flags;
+
+ sch = to_subchannel(pdev);
+ if (sch->dev.driver_data) {
+ /*
+ * This subchannel already has an associated ccw_device.
+ * Register it and exit. This happens for all early
+ * device, e.g. the console.
+ */
+ cdev = sch->dev.driver_data;
+ device_initialize(&cdev->dev);
+ ccw_device_register(cdev);
+ subchannel_add_files(&sch->dev);
+ /*
+ * Check if the device is already online. If it is
+ * the reference count needs to be corrected
+ * (see ccw_device_online and css_init_done for the
+ * ugly details).
+ */
+ if (cdev->private->state != DEV_STATE_NOT_OPER &&
+ cdev->private->state != DEV_STATE_OFFLINE &&
+ cdev->private->state != DEV_STATE_BOXED)
+ get_device(&cdev->dev);
+ return 0;
+ }
+ cdev = kmalloc (sizeof(*cdev), GFP_KERNEL);
+ if (!cdev)
+ return -ENOMEM;
+ memset(cdev, 0, sizeof(struct ccw_device));
+ cdev->private = kmalloc(sizeof(struct ccw_device_private),
+ GFP_KERNEL | GFP_DMA);
+ if (!cdev->private) {
+ kfree(cdev);
+ return -ENOMEM;
+ }
+ memset(cdev->private, 0, sizeof(struct ccw_device_private));
+ atomic_set(&cdev->private->onoff, 0);
+ cdev->dev = (struct device) {
+ .parent = pdev,
+ .release = ccw_device_release,
+ };
+ INIT_LIST_HEAD(&cdev->private->kick_work.entry);
+ /* Do first half of device_register. */
+ device_initialize(&cdev->dev);
+
+ if (!get_device(&sch->dev)) {
+ if (cdev->dev.release)
+ cdev->dev.release(&cdev->dev);
+ return -ENODEV;
+ }
+
+ rc = io_subchannel_recog(cdev, to_subchannel(pdev));
+ if (rc) {
+ spin_lock_irqsave(&sch->lock, flags);
+ sch->dev.driver_data = NULL;
+ spin_unlock_irqrestore(&sch->lock, flags);
+ if (cdev->dev.release)
+ cdev->dev.release(&cdev->dev);
+ }
+
+ return rc;
+}
+
+static void
+ccw_device_unregister(void *data)
+{
+ struct ccw_device *cdev;
+
+ cdev = (struct ccw_device *)data;
+ if (test_and_clear_bit(1, &cdev->private->registered))
+ device_unregister(&cdev->dev);
+ put_device(&cdev->dev);
+}
+
+static int
+io_subchannel_remove (struct device *dev)
+{
+ struct ccw_device *cdev;
+ unsigned long flags;
+
+ if (!dev->driver_data)
+ return 0;
+ cdev = dev->driver_data;
+ /* Set ccw device to not operational and drop reference. */
+ spin_lock_irqsave(cdev->ccwlock, flags);
+ dev->driver_data = NULL;
+ cdev->private->state = DEV_STATE_NOT_OPER;
+ spin_unlock_irqrestore(cdev->ccwlock, flags);
+ /*
+ * Put unregistration on workqueue to avoid livelocks on the css bus
+ * semaphore.
+ */
+ if (get_device(&cdev->dev)) {
+ PREPARE_WORK(&cdev->private->kick_work,
+ ccw_device_unregister, (void *) cdev);
+ queue_work(ccw_device_work, &cdev->private->kick_work);
+ }
+ return 0;
+}
+
+static int
+io_subchannel_notify(struct device *dev, int event)
+{
+ struct ccw_device *cdev;
+
+ cdev = dev->driver_data;
+ if (!cdev)
+ return 0;
+ if (!cdev->drv)
+ return 0;
+ if (!cdev->online)
+ return 0;
+ return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
+}
+
+static void
+io_subchannel_verify(struct device *dev)
+{
+ struct ccw_device *cdev;
+
+ cdev = dev->driver_data;
+ if (cdev)
+ dev_fsm_event(cdev, DEV_EVENT_VERIFY);
+}
+
+static void
+io_subchannel_ioterm(struct device *dev)
+{
+ struct ccw_device *cdev;
+
+ cdev = dev->driver_data;
+ if (!cdev)
+ return;
+ cdev->private->state = DEV_STATE_CLEAR_VERIFY;
+ if (cdev->handler)
+ cdev->handler(cdev, cdev->private->intparm,
+ ERR_PTR(-EIO));
+}
+
+static void
+io_subchannel_shutdown(struct device *dev)
+{
+ struct subchannel *sch;
+ struct ccw_device *cdev;
+ int ret;
+
+ sch = to_subchannel(dev);
+ cdev = dev->driver_data;
+
+ if (cio_is_console(sch->irq))
+ return;
+ if (!sch->schib.pmcw.ena)
+ /* Nothing to do. */
+ return;
+ ret = cio_disable_subchannel(sch);
+ if (ret != -EBUSY)
+ /* Subchannel is disabled, we're done. */
+ return;
+ cdev->private->state = DEV_STATE_QUIESCE;
+ if (cdev->handler)
+ cdev->handler(cdev, cdev->private->intparm,
+ ERR_PTR(-EIO));
+ ret = ccw_device_cancel_halt_clear(cdev);
+ if (ret == -EBUSY) {
+ ccw_device_set_timeout(cdev, HZ/10);
+ wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
+ }
+ cio_disable_subchannel(sch);
+}
+
+#ifdef CONFIG_CCW_CONSOLE
+static struct ccw_device console_cdev;
+static struct ccw_device_private console_private;
+static int console_cdev_in_use;
+
+static int
+ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
+{
+ int rc;
+
+ /* Initialize the ccw_device structure. */
+ cdev->dev = (struct device) {
+ .parent = &sch->dev,
+ };
+ /* Initialize the subchannel structure */
+ sch->dev.parent = &css_bus_device;
+ sch->dev.bus = &css_bus_type;
+
+ rc = io_subchannel_recog(cdev, sch);
+ if (rc)
+ return rc;
+
+ /* Now wait for the async. recognition to come to an end. */
+ spin_lock_irq(cdev->ccwlock);
+ while (!dev_fsm_final_state(cdev))
+ wait_cons_dev();
+ rc = -EIO;
+ if (cdev->private->state != DEV_STATE_OFFLINE)
+ goto out_unlock;
+ ccw_device_online(cdev);
+ while (!dev_fsm_final_state(cdev))
+ wait_cons_dev();
+ if (cdev->private->state != DEV_STATE_ONLINE)
+ goto out_unlock;
+ rc = 0;
+out_unlock:
+ spin_unlock_irq(cdev->ccwlock);
+ return 0;
+}
+
+struct ccw_device *
+ccw_device_probe_console(void)
+{
+ struct subchannel *sch;
+ int ret;
+
+ if (xchg(&console_cdev_in_use, 1) != 0)
+ return NULL;
+ sch = cio_probe_console();
+ if (IS_ERR(sch)) {
+ console_cdev_in_use = 0;
+ return (void *) sch;
+ }
+ memset(&console_cdev, 0, sizeof(struct ccw_device));
+ memset(&console_private, 0, sizeof(struct ccw_device_private));
+ console_cdev.private = &console_private;
+ ret = ccw_device_console_enable(&console_cdev, sch);
+ if (ret) {
+ cio_release_console();
+ console_cdev_in_use = 0;
+ return ERR_PTR(ret);
+ }
+ console_cdev.online = 1;
+ return &console_cdev;
+}
+#endif
+
+/*
+ * get ccw_device matching the busid, but only if owned by cdrv
+ */
+struct ccw_device *
+get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
+{
+ struct device *d, *dev;
+ struct device_driver *drv;
+
+ drv = get_driver(&cdrv->driver);
+ if (!drv)
+ return 0;
+
+ down_read(&drv->bus->subsys.rwsem);
+
+ dev = NULL;
+ list_for_each_entry(d, &drv->devices, driver_list) {
+ dev = get_device(d);
+
+ if (dev && !strncmp(bus_id, dev->bus_id, BUS_ID_SIZE))
+ break;
+ else if (dev) {
+ put_device(dev);
+ dev = NULL;
+ }
+ }
+ up_read(&drv->bus->subsys.rwsem);
+ put_driver(drv);
+
+ return dev ? to_ccwdev(dev) : 0;
+}
+
+/************************** device driver handling ************************/
+
+/* This is the implementation of the ccw_driver class. The probe, remove
+ * and release methods are initially very similar to the device_driver
+ * implementations, with the difference that they have ccw_device
+ * arguments.
+ *
+ * A ccw driver also contains the information that is needed for
+ * device matching.
+ */
+static int
+ccw_device_probe (struct device *dev)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
+ int ret;
+
+ cdev->drv = cdrv; /* to let the driver call _set_online */
+
+ ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
+
+ if (ret) {
+ cdev->drv = 0;
+ return ret;
+ }
+
+ return 0;
+}
+
+static int
+ccw_device_remove (struct device *dev)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct ccw_driver *cdrv = cdev->drv;
+ int ret;
+
+ pr_debug("removing device %s\n", cdev->dev.bus_id);
+ if (cdrv->remove)
+ cdrv->remove(cdev);
+ if (cdev->online) {
+ cdev->online = 0;
+ spin_lock_irq(cdev->ccwlock);
+ ret = ccw_device_offline(cdev);
+ spin_unlock_irq(cdev->ccwlock);
+ if (ret == 0)
+ wait_event(cdev->private->wait_q,
+ dev_fsm_final_state(cdev));
+ else
+ //FIXME: we can't fail!
+ pr_debug("ccw_device_offline returned %d, device %s\n",
+ ret, cdev->dev.bus_id);
+ }
+ ccw_device_set_timeout(cdev, 0);
+ cdev->drv = 0;
+ return 0;
+}
+
+int
+ccw_driver_register (struct ccw_driver *cdriver)
+{
+ struct device_driver *drv = &cdriver->driver;
+
+ drv->bus = &ccw_bus_type;
+ drv->name = cdriver->name;
+ drv->probe = ccw_device_probe;
+ drv->remove = ccw_device_remove;
+
+ return driver_register(drv);
+}
+
+void
+ccw_driver_unregister (struct ccw_driver *cdriver)
+{
+ driver_unregister(&cdriver->driver);
+}
+
+MODULE_LICENSE("GPL");
+EXPORT_SYMBOL(ccw_device_set_online);
+EXPORT_SYMBOL(ccw_device_set_offline);
+EXPORT_SYMBOL(ccw_driver_register);
+EXPORT_SYMBOL(ccw_driver_unregister);
+EXPORT_SYMBOL(get_ccwdev_by_busid);
+EXPORT_SYMBOL(ccw_bus_type);
+EXPORT_SYMBOL(ccw_device_work);
+EXPORT_SYMBOL(ccw_device_notify_work);
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-25 09:47:41 +0300