summaryrefslogtreecommitdiff
path: root/drivers/base/dd.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/base/dd.c')
-rw-r--r--drivers/base/dd.c778
1 files changed, 546 insertions, 232 deletions
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 8ac10af17c00..349f31bedfa1 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -19,14 +19,16 @@
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/delay.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-map-ops.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kthread.h>
#include <linux/wait.h>
#include <linux/async.h>
+#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/pinctrl/devinfo.h>
+#include <linux/slab.h>
#include "base.h"
#include "power/power.h"
@@ -54,9 +56,13 @@ static DEFINE_MUTEX(deferred_probe_mutex);
static LIST_HEAD(deferred_probe_pending_list);
static LIST_HEAD(deferred_probe_active_list);
static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
-static struct dentry *deferred_devices;
static bool initcalls_done;
+/* Save the async probe drivers' name from kernel cmdline */
+#define ASYNC_DRV_NAMES_MAX_LEN 256
+static char async_probe_drv_names[ASYNC_DRV_NAMES_MAX_LEN];
+static bool async_probe_default;
+
/*
* In some cases, like suspend to RAM or hibernation, It might be reasonable
* to prohibit probing of devices as it could be unsafe.
@@ -64,6 +70,12 @@ static bool initcalls_done;
*/
static bool defer_all_probes;
+static void __device_set_deferred_probe_reason(const struct device *dev, char *reason)
+{
+ kfree(dev->p->deferred_probe_reason);
+ dev->p->deferred_probe_reason = reason;
+}
+
/*
* deferred_probe_work_func() - Retry probing devices in the active list.
*/
@@ -92,6 +104,8 @@ static void deferred_probe_work_func(struct work_struct *work)
get_device(dev);
+ __device_set_deferred_probe_reason(dev, NULL);
+
/*
* Drop the mutex while probing each device; the probe path may
* manipulate the deferred list
@@ -116,8 +130,11 @@ static void deferred_probe_work_func(struct work_struct *work)
}
static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func);
-static void driver_deferred_probe_add(struct device *dev)
+void driver_deferred_probe_add(struct device *dev)
{
+ if (!dev->can_match)
+ return;
+
mutex_lock(&deferred_probe_mutex);
if (list_empty(&dev->p->deferred_probe)) {
dev_dbg(dev, "Added to deferred list\n");
@@ -132,11 +149,12 @@ void driver_deferred_probe_del(struct device *dev)
if (!list_empty(&dev->p->deferred_probe)) {
dev_dbg(dev, "Removed from deferred list\n");
list_del_init(&dev->p->deferred_probe);
+ __device_set_deferred_probe_reason(dev, NULL);
}
mutex_unlock(&deferred_probe_mutex);
}
-static bool driver_deferred_probe_enable = false;
+static bool driver_deferred_probe_enable;
/**
* driver_deferred_probe_trigger() - Kick off re-probing deferred devices
*
@@ -155,7 +173,7 @@ static bool driver_deferred_probe_enable = false;
* changes in the midst of a probe, then deferred processing should be triggered
* again.
*/
-static void driver_deferred_probe_trigger(void)
+void driver_deferred_probe_trigger(void)
{
if (!driver_deferred_probe_enable)
return;
@@ -175,7 +193,7 @@ static void driver_deferred_probe_trigger(void)
* Kick the re-probe thread. It may already be scheduled, but it is
* safe to kick it again.
*/
- schedule_work(&deferred_probe_work);
+ queue_work(system_dfl_wq, &deferred_probe_work);
}
/**
@@ -202,6 +220,24 @@ void device_unblock_probing(void)
driver_deferred_probe_trigger();
}
+/**
+ * device_set_deferred_probe_reason() - Set defer probe reason message for device
+ * @dev: the pointer to the struct device
+ * @vaf: the pointer to va_format structure with message
+ */
+void device_set_deferred_probe_reason(const struct device *dev, struct va_format *vaf)
+{
+ const char *drv = dev_driver_string(dev);
+ char *reason;
+
+ mutex_lock(&deferred_probe_mutex);
+
+ reason = kasprintf(GFP_KERNEL, "%s: %pV", drv, vaf);
+ __device_set_deferred_probe_reason(dev, reason);
+
+ mutex_unlock(&deferred_probe_mutex);
+}
+
/*
* deferred_devs_show() - Show the devices in the deferred probe pending list.
*/
@@ -212,7 +248,8 @@ static int deferred_devs_show(struct seq_file *s, void *data)
mutex_lock(&deferred_probe_mutex);
list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe)
- seq_printf(s, "%s\n", dev_name(curr->device));
+ seq_printf(s, "%s\t%s", dev_name(curr->device),
+ curr->deferred_probe_reason ?: "\n");
mutex_unlock(&deferred_probe_mutex);
@@ -220,13 +257,18 @@ static int deferred_devs_show(struct seq_file *s, void *data)
}
DEFINE_SHOW_ATTRIBUTE(deferred_devs);
-static int deferred_probe_timeout = -1;
+#ifdef CONFIG_MODULES
+static int driver_deferred_probe_timeout = 10;
+#else
+static int driver_deferred_probe_timeout;
+#endif
+
static int __init deferred_probe_timeout_setup(char *str)
{
int timeout;
if (!kstrtoint(str, 10, &timeout))
- deferred_probe_timeout = timeout;
+ driver_deferred_probe_timeout = timeout;
return 1;
}
__setup("deferred_probe_timeout=", deferred_probe_timeout_setup);
@@ -235,39 +277,64 @@ __setup("deferred_probe_timeout=", deferred_probe_timeout_setup);
* driver_deferred_probe_check_state() - Check deferred probe state
* @dev: device to check
*
- * Returns -ENODEV if init is done and all built-in drivers have had a chance
- * to probe (i.e. initcalls are done), -ETIMEDOUT if deferred probe debug
- * timeout has expired, or -EPROBE_DEFER if none of those conditions are met.
+ * Return:
+ * * -ENODEV if initcalls have completed and modules are disabled.
+ * * -ETIMEDOUT if the deferred probe timeout was set and has expired
+ * and modules are enabled.
+ * * -EPROBE_DEFER in other cases.
*
* Drivers or subsystems can opt-in to calling this function instead of directly
* returning -EPROBE_DEFER.
*/
int driver_deferred_probe_check_state(struct device *dev)
{
- if (initcalls_done) {
- if (!deferred_probe_timeout) {
- dev_WARN(dev, "deferred probe timeout, ignoring dependency");
- return -ETIMEDOUT;
- }
- dev_warn(dev, "ignoring dependency for device, assuming no driver");
+ if (!IS_ENABLED(CONFIG_MODULES) && initcalls_done) {
+ dev_warn(dev, "ignoring dependency for device, assuming no driver\n");
return -ENODEV;
}
+
+ if (!driver_deferred_probe_timeout && initcalls_done) {
+ dev_warn(dev, "deferred probe timeout, ignoring dependency\n");
+ return -ETIMEDOUT;
+ }
+
return -EPROBE_DEFER;
}
+EXPORT_SYMBOL_GPL(driver_deferred_probe_check_state);
static void deferred_probe_timeout_work_func(struct work_struct *work)
{
- struct device_private *private, *p;
+ struct device_private *p;
- deferred_probe_timeout = 0;
+ fw_devlink_drivers_done();
+
+ driver_deferred_probe_timeout = 0;
driver_deferred_probe_trigger();
flush_work(&deferred_probe_work);
- list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe)
- dev_info(private->device, "deferred probe pending");
+ mutex_lock(&deferred_probe_mutex);
+ list_for_each_entry(p, &deferred_probe_pending_list, deferred_probe)
+ dev_warn(p->device, "deferred probe pending: %s", p->deferred_probe_reason ?: "(reason unknown)\n");
+ mutex_unlock(&deferred_probe_mutex);
+
+ fw_devlink_probing_done();
}
static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func);
+void deferred_probe_extend_timeout(void)
+{
+ /*
+ * If the work hasn't been queued yet or if the work expired, don't
+ * start a new one.
+ */
+ if (cancel_delayed_work(&deferred_probe_timeout_work)) {
+ schedule_delayed_work(&deferred_probe_timeout_work,
+ driver_deferred_probe_timeout * HZ);
+ pr_debug("Extended deferred probe timeout by %d secs\n",
+ driver_deferred_probe_timeout);
+ }
+}
+
/**
* deferred_probe_initcall() - Enable probing of deferred devices
*
@@ -277,8 +344,8 @@ static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_
*/
static int deferred_probe_initcall(void)
{
- deferred_devices = debugfs_create_file("devices_deferred", 0444, NULL,
- NULL, &deferred_devs_fops);
+ debugfs_create_file("devices_deferred", 0444, NULL, NULL,
+ &deferred_devs_fops);
driver_deferred_probe_enable = true;
driver_deferred_probe_trigger();
@@ -286,6 +353,9 @@ static int deferred_probe_initcall(void)
flush_work(&deferred_probe_work);
initcalls_done = true;
+ if (!IS_ENABLED(CONFIG_MODULES))
+ fw_devlink_drivers_done();
+
/*
* Trigger deferred probe again, this time we won't defer anything
* that is optional
@@ -293,17 +363,21 @@ static int deferred_probe_initcall(void)
driver_deferred_probe_trigger();
flush_work(&deferred_probe_work);
- if (deferred_probe_timeout > 0) {
+ if (driver_deferred_probe_timeout > 0) {
schedule_delayed_work(&deferred_probe_timeout_work,
- deferred_probe_timeout * HZ);
+ driver_deferred_probe_timeout * HZ);
}
+
+ if (!IS_ENABLED(CONFIG_MODULES))
+ fw_devlink_probing_done();
+
return 0;
}
late_initcall(deferred_probe_initcall);
static void __exit deferred_probe_exit(void)
{
- debugfs_remove_recursive(deferred_devices);
+ debugfs_lookup_and_remove("devices_deferred", NULL);
}
__exitcall(deferred_probe_exit);
@@ -320,17 +394,17 @@ bool device_is_bound(struct device *dev)
{
return dev->p && klist_node_attached(&dev->p->knode_driver);
}
+EXPORT_SYMBOL_GPL(device_is_bound);
static void driver_bound(struct device *dev)
{
if (device_is_bound(dev)) {
- printk(KERN_WARNING "%s: device %s already bound\n",
- __func__, kobject_name(&dev->kobj));
+ dev_warn(dev, "%s: device already bound\n", __func__);
return;
}
- pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name,
- __func__, dev_name(dev));
+ dev_dbg(dev, "driver: '%s': %s: bound to device\n", dev->driver->name,
+ __func__);
klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices);
device_links_driver_bound(dev);
@@ -344,10 +418,7 @@ static void driver_bound(struct device *dev)
driver_deferred_probe_del(dev);
driver_deferred_probe_trigger();
- if (dev->bus)
- blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
- BUS_NOTIFY_BOUND_DRIVER, dev);
-
+ bus_notify(dev, BUS_NOTIFY_BOUND_DRIVER);
kobject_uevent(&dev->kobj, KOBJ_BIND);
}
@@ -366,9 +437,7 @@ static int driver_sysfs_add(struct device *dev)
{
int ret;
- if (dev->bus)
- blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
- BUS_NOTIFY_BIND_DRIVER, dev);
+ bus_notify(dev, BUS_NOTIFY_BIND_DRIVER);
ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj,
kobject_name(&dev->kobj));
@@ -380,8 +449,11 @@ static int driver_sysfs_add(struct device *dev)
if (ret)
goto rm_dev;
- if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump ||
- !device_create_file(dev, &dev_attr_coredump))
+ if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump)
+ return 0;
+
+ ret = device_create_file(dev, &dev_attr_coredump);
+ if (!ret)
return 0;
sysfs_remove_link(&dev->kobj, "driver");
@@ -413,23 +485,25 @@ static void driver_sysfs_remove(struct device *dev)
* Allow manual attachment of a driver to a device.
* Caller must have already set @dev->driver.
*
- * Note that this does not modify the bus reference count
- * nor take the bus's rwsem. Please verify those are accounted
- * for before calling this. (It is ok to call with no other effort
- * from a driver's probe() method.)
+ * Note that this does not modify the bus reference count.
+ * Please verify that is accounted for before calling this.
+ * (It is ok to call with no other effort from a driver's probe() method.)
*
* This function must be called with the device lock held.
+ *
+ * Callers should prefer to use device_driver_attach() instead.
*/
int device_bind_driver(struct device *dev)
{
int ret;
ret = driver_sysfs_add(dev);
- if (!ret)
+ if (!ret) {
+ device_links_force_bind(dev);
driver_bound(dev);
- else if (dev->bus)
- blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
- BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
+ }
+ else
+ bus_notify(dev, BUS_NOTIFY_DRIVER_NOT_BOUND);
return ret;
}
EXPORT_SYMBOL_GPL(device_bind_driver);
@@ -437,21 +511,102 @@ EXPORT_SYMBOL_GPL(device_bind_driver);
static atomic_t probe_count = ATOMIC_INIT(0);
static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
-static void driver_deferred_probe_add_trigger(struct device *dev,
- int local_trigger_count)
+static ssize_t state_synced_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int ret = 0;
+
+ if (strcmp("1", buf))
+ return -EINVAL;
+
+ device_lock(dev);
+ if (!dev->state_synced) {
+ dev->state_synced = true;
+ dev_sync_state(dev);
+ } else {
+ ret = -EINVAL;
+ }
+ device_unlock(dev);
+
+ return ret ? ret : count;
+}
+
+static ssize_t state_synced_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ bool val;
+
+ device_lock(dev);
+ val = dev->state_synced;
+ device_unlock(dev);
+
+ return sysfs_emit(buf, "%u\n", val);
+}
+static DEVICE_ATTR_RW(state_synced);
+
+static void device_unbind_cleanup(struct device *dev)
+{
+ devres_release_all(dev);
+ arch_teardown_dma_ops(dev);
+ kfree(dev->dma_range_map);
+ dev->dma_range_map = NULL;
+ device_set_driver(dev, NULL);
+ dev_set_drvdata(dev, NULL);
+ dev_pm_domain_detach(dev, dev->power.detach_power_off);
+ if (dev->pm_domain && dev->pm_domain->dismiss)
+ dev->pm_domain->dismiss(dev);
+ pm_runtime_reinit(dev);
+ dev_pm_set_driver_flags(dev, 0);
+}
+
+static void device_remove(struct device *dev)
+{
+ device_remove_file(dev, &dev_attr_state_synced);
+ device_remove_groups(dev, dev->driver->dev_groups);
+
+ if (dev->bus && dev->bus->remove)
+ dev->bus->remove(dev);
+ else if (dev->driver->remove)
+ dev->driver->remove(dev);
+}
+
+static int call_driver_probe(struct device *dev, const struct device_driver *drv)
{
- driver_deferred_probe_add(dev);
- /* Did a trigger occur while probing? Need to re-trigger if yes */
- if (local_trigger_count != atomic_read(&deferred_trigger_count))
- driver_deferred_probe_trigger();
+ int ret = 0;
+
+ if (dev->bus->probe)
+ ret = dev->bus->probe(dev);
+ else if (drv->probe)
+ ret = drv->probe(dev);
+
+ switch (ret) {
+ case 0:
+ break;
+ case -EPROBE_DEFER:
+ /* Driver requested deferred probing */
+ dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name);
+ break;
+ case -ENODEV:
+ case -ENXIO:
+ dev_dbg(dev, "probe with driver %s rejects match %d\n",
+ drv->name, ret);
+ break;
+ default:
+ /* driver matched but the probe failed */
+ dev_err(dev, "probe with driver %s failed with error %d\n",
+ drv->name, ret);
+ break;
+ }
+
+ return ret;
}
-static int really_probe(struct device *dev, struct device_driver *drv)
+static int really_probe(struct device *dev, const struct device_driver *drv)
{
- int ret = -EPROBE_DEFER;
- int local_trigger_count = atomic_read(&deferred_trigger_count);
bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) &&
!drv->suppress_bind_attrs;
+ int ret, link_ret;
if (defer_all_probes) {
/*
@@ -460,23 +615,23 @@ static int really_probe(struct device *dev, struct device_driver *drv)
* wait_for_device_probe() right after that to avoid any races.
*/
dev_dbg(dev, "Driver %s force probe deferral\n", drv->name);
- driver_deferred_probe_add(dev);
- return ret;
+ return -EPROBE_DEFER;
}
- ret = device_links_check_suppliers(dev);
- if (ret == -EPROBE_DEFER)
- driver_deferred_probe_add_trigger(dev, local_trigger_count);
- if (ret)
- return ret;
+ link_ret = device_links_check_suppliers(dev);
+ if (link_ret == -EPROBE_DEFER)
+ return link_ret;
- atomic_inc(&probe_count);
- pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
- drv->bus->name, __func__, drv->name, dev_name(dev));
- WARN_ON(!list_empty(&dev->devres_head));
+ dev_dbg(dev, "bus: '%s': %s: probing driver %s with device\n",
+ drv->bus->name, __func__, drv->name);
+ if (!list_empty(&dev->devres_head)) {
+ dev_crit(dev, "Resources present before probing\n");
+ ret = -EBUSY;
+ goto done;
+ }
re_probe:
- dev->driver = drv;
+ device_set_driver(dev, drv);
/* If using pinctrl, bind pins now before probing */
ret = pinctrl_bind_pins(dev);
@@ -486,13 +641,13 @@ re_probe:
if (dev->bus->dma_configure) {
ret = dev->bus->dma_configure(dev);
if (ret)
- goto dma_failed;
+ goto pinctrl_bind_failed;
}
- if (driver_sysfs_add(dev)) {
- printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
- __func__, dev_name(dev));
- goto probe_failed;
+ ret = driver_sysfs_add(dev);
+ if (ret) {
+ dev_err(dev, "%s: driver_sysfs_add failed\n", __func__);
+ goto sysfs_failed;
}
if (dev->pm_domain && dev->pm_domain->activate) {
@@ -501,31 +656,47 @@ re_probe:
goto probe_failed;
}
- if (dev->bus->probe) {
- ret = dev->bus->probe(dev);
- if (ret)
- goto probe_failed;
- } else if (drv->probe) {
- ret = drv->probe(dev);
- if (ret)
- goto probe_failed;
+ ret = call_driver_probe(dev, drv);
+ if (ret) {
+ /*
+ * If fw_devlink_best_effort is active (denoted by -EAGAIN), the
+ * device might actually probe properly once some of its missing
+ * suppliers have probed. So, treat this as if the driver
+ * returned -EPROBE_DEFER.
+ */
+ if (link_ret == -EAGAIN)
+ ret = -EPROBE_DEFER;
+
+ /*
+ * Return probe errors as positive values so that the callers
+ * can distinguish them from other errors.
+ */
+ ret = -ret;
+ goto probe_failed;
+ }
+
+ ret = device_add_groups(dev, drv->dev_groups);
+ if (ret) {
+ dev_err(dev, "device_add_groups() failed\n");
+ goto dev_groups_failed;
+ }
+
+ if (dev_has_sync_state(dev)) {
+ ret = device_create_file(dev, &dev_attr_state_synced);
+ if (ret) {
+ dev_err(dev, "state_synced sysfs add failed\n");
+ goto dev_sysfs_state_synced_failed;
+ }
}
if (test_remove) {
test_remove = false;
- if (dev->bus->remove)
- dev->bus->remove(dev);
- else if (drv->remove)
- drv->remove(dev);
-
- devres_release_all(dev);
+ device_remove(dev);
driver_sysfs_remove(dev);
- dev->driver = NULL;
- dev_set_drvdata(dev, NULL);
- if (dev->pm_domain && dev->pm_domain->dismiss)
- dev->pm_domain->dismiss(dev);
- pm_runtime_reinit(dev);
+ if (dev->bus && dev->bus->dma_cleanup)
+ dev->bus->dma_cleanup(dev);
+ device_unbind_cleanup(dev);
goto re_probe;
}
@@ -536,70 +707,44 @@ re_probe:
dev->pm_domain->sync(dev);
driver_bound(dev);
- ret = 1;
- pr_debug("bus: '%s': %s: bound device %s to driver %s\n",
- drv->bus->name, __func__, dev_name(dev), drv->name);
+ dev_dbg(dev, "bus: '%s': %s: bound device to driver %s\n",
+ drv->bus->name, __func__, drv->name);
goto done;
+dev_sysfs_state_synced_failed:
+dev_groups_failed:
+ device_remove(dev);
probe_failed:
- arch_teardown_dma_ops(dev);
-dma_failed:
- if (dev->bus)
- blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
- BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
+ driver_sysfs_remove(dev);
+sysfs_failed:
+ bus_notify(dev, BUS_NOTIFY_DRIVER_NOT_BOUND);
+ if (dev->bus && dev->bus->dma_cleanup)
+ dev->bus->dma_cleanup(dev);
pinctrl_bind_failed:
device_links_no_driver(dev);
- devres_release_all(dev);
- driver_sysfs_remove(dev);
- dev->driver = NULL;
- dev_set_drvdata(dev, NULL);
- if (dev->pm_domain && dev->pm_domain->dismiss)
- dev->pm_domain->dismiss(dev);
- pm_runtime_reinit(dev);
- dev_pm_set_driver_flags(dev, 0);
-
- switch (ret) {
- case -EPROBE_DEFER:
- /* Driver requested deferred probing */
- dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name);
- driver_deferred_probe_add_trigger(dev, local_trigger_count);
- break;
- case -ENODEV:
- case -ENXIO:
- pr_debug("%s: probe of %s rejects match %d\n",
- drv->name, dev_name(dev), ret);
- break;
- default:
- /* driver matched but the probe failed */
- printk(KERN_WARNING
- "%s: probe of %s failed with error %d\n",
- drv->name, dev_name(dev), ret);
- }
- /*
- * Ignore errors returned by ->probe so that the next driver can try
- * its luck.
- */
- ret = 0;
+ device_unbind_cleanup(dev);
done:
- atomic_dec(&probe_count);
- wake_up(&probe_waitqueue);
return ret;
}
/*
* For initcall_debug, show the driver probe time.
*/
-static int really_probe_debug(struct device *dev, struct device_driver *drv)
+static int really_probe_debug(struct device *dev, const struct device_driver *drv)
{
- ktime_t calltime, delta, rettime;
+ ktime_t calltime, rettime;
int ret;
calltime = ktime_get();
ret = really_probe(dev, drv);
rettime = ktime_get();
- delta = ktime_sub(rettime, calltime);
+ /*
+ * Don't change this to pr_debug() because that requires
+ * CONFIG_DYNAMIC_DEBUG and we want a simple 'initcall_debug' on the
+ * kernel commandline to print this all the time at the debug level.
+ */
printk(KERN_DEBUG "probe of %s returned %d after %lld usecs\n",
- dev_name(dev), ret, (s64) ktime_to_us(delta));
+ dev_name(dev), ret, ktime_us_delta(rettime, calltime));
return ret;
}
@@ -609,13 +754,12 @@ static int really_probe_debug(struct device *dev, struct device_driver *drv)
*
* Should somehow figure out how to use a semaphore, not an atomic variable...
*/
-int driver_probe_done(void)
+bool __init driver_probe_done(void)
{
- pr_debug("%s: probe_count = %d\n", __func__,
- atomic_read(&probe_count));
- if (atomic_read(&probe_count))
- return -EBUSY;
- return 0;
+ int local_probe_count = atomic_read(&probe_count);
+
+ pr_debug("%s: probe_count = %d\n", __func__, local_probe_count);
+ return !local_probe_count;
}
/**
@@ -633,28 +777,18 @@ void wait_for_device_probe(void)
}
EXPORT_SYMBOL_GPL(wait_for_device_probe);
-/**
- * driver_probe_device - attempt to bind device & driver together
- * @drv: driver to bind a device to
- * @dev: device to try to bind to the driver
- *
- * This function returns -ENODEV if the device is not registered,
- * 1 if the device is bound successfully and 0 otherwise.
- *
- * This function must be called with @dev lock held. When called for a
- * USB interface, @dev->parent lock must be held as well.
- *
- * If the device has a parent, runtime-resume the parent before driver probing.
- */
-int driver_probe_device(struct device_driver *drv, struct device *dev)
+static int __driver_probe_device(const struct device_driver *drv, struct device *dev)
{
int ret = 0;
- if (!device_is_registered(dev))
+ if (dev->p->dead || !device_is_registered(dev))
return -ENODEV;
+ if (dev->driver)
+ return -EBUSY;
- pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
- drv->bus->name, __func__, dev_name(dev), drv->name);
+ dev->can_match = true;
+ dev_dbg(dev, "bus: '%s': %s: matched device with driver %s\n",
+ drv->bus->name, __func__, drv->name);
pm_runtime_get_suppliers(dev);
if (dev->parent)
@@ -674,7 +808,65 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
return ret;
}
-bool driver_allows_async_probing(struct device_driver *drv)
+/**
+ * driver_probe_device - attempt to bind device & driver together
+ * @drv: driver to bind a device to
+ * @dev: device to try to bind to the driver
+ *
+ * This function returns -ENODEV if the device is not registered, -EBUSY if it
+ * already has a driver, 0 if the device is bound successfully and a positive
+ * (inverted) error code for failures from the ->probe method.
+ *
+ * This function must be called with @dev lock held. When called for a
+ * USB interface, @dev->parent lock must be held as well.
+ *
+ * If the device has a parent, runtime-resume the parent before driver probing.
+ */
+static int driver_probe_device(const struct device_driver *drv, struct device *dev)
+{
+ int trigger_count = atomic_read(&deferred_trigger_count);
+ int ret;
+
+ atomic_inc(&probe_count);
+ ret = __driver_probe_device(drv, dev);
+ if (ret == -EPROBE_DEFER || ret == EPROBE_DEFER) {
+ driver_deferred_probe_add(dev);
+
+ /*
+ * Did a trigger occur while probing? Need to re-trigger if yes
+ */
+ if (trigger_count != atomic_read(&deferred_trigger_count) &&
+ !defer_all_probes)
+ driver_deferred_probe_trigger();
+ }
+ atomic_dec(&probe_count);
+ wake_up_all(&probe_waitqueue);
+ return ret;
+}
+
+static inline bool cmdline_requested_async_probing(const char *drv_name)
+{
+ bool async_drv;
+
+ async_drv = parse_option_str(async_probe_drv_names, drv_name);
+
+ return (async_probe_default != async_drv);
+}
+
+/* The option format is "driver_async_probe=drv_name1,drv_name2,..." */
+static int __init save_async_options(char *buf)
+{
+ if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN)
+ pr_warn("Too long list of driver names for 'driver_async_probe'!\n");
+
+ strscpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN);
+ async_probe_default = parse_option_str(async_probe_drv_names, "*");
+
+ return 1;
+}
+__setup("driver_async_probe=", save_async_options);
+
+static bool driver_allows_async_probing(const struct device_driver *drv)
{
switch (drv->probe_type) {
case PROBE_PREFER_ASYNCHRONOUS:
@@ -684,6 +876,9 @@ bool driver_allows_async_probing(struct device_driver *drv)
return false;
default:
+ if (cmdline_requested_async_probing(drv->name))
+ return true;
+
if (module_requested_async_probing(drv->owner))
return true;
@@ -695,7 +890,7 @@ struct device_attach_data {
struct device *dev;
/*
- * Indicates whether we are are considering asynchronous probing or
+ * Indicates whether we are considering asynchronous probing or
* not. Only initial binding after device or driver registration
* (including deferral processing) may be done asynchronously, the
* rest is always synchronous, as we expect it is being done by
@@ -731,24 +926,21 @@ static int __device_attach_driver(struct device_driver *drv, void *_data)
bool async_allowed;
int ret;
- /*
- * Check if device has already been claimed. This may
- * happen with driver loading, device discovery/registration,
- * and deferred probe processing happens all at once with
- * multiple threads.
- */
- if (dev->driver)
- return -EBUSY;
-
ret = driver_match_device(drv, dev);
if (ret == 0) {
/* no match */
return 0;
} else if (ret == -EPROBE_DEFER) {
dev_dbg(dev, "Device match requests probe deferral\n");
+ dev->can_match = true;
driver_deferred_probe_add(dev);
+ /*
+ * Device can't match with a driver right now, so don't attempt
+ * to match or bind with other drivers on the bus.
+ */
+ return ret;
} else if (ret < 0) {
- dev_dbg(dev, "Bus failed to match device: %d", ret);
+ dev_dbg(dev, "Bus failed to match device: %d\n", ret);
return ret;
} /* ret > 0 means positive match */
@@ -760,7 +952,14 @@ static int __device_attach_driver(struct device_driver *drv, void *_data)
if (data->check_async && async_allowed != data->want_async)
return 0;
- return driver_probe_device(drv, dev);
+ /*
+ * Ignore errors returned by ->probe so that the next driver can try
+ * its luck.
+ */
+ ret = driver_probe_device(drv, dev);
+ if (ret < 0)
+ return ret;
+ return ret == 0;
}
static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
@@ -774,6 +973,15 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
device_lock(dev);
+ /*
+ * Check if device has already been removed or claimed. This may
+ * happen with driver loading, device discovery/registration,
+ * and deferred probe processing happens all at once with
+ * multiple threads.
+ */
+ if (dev->p->dead || dev->driver)
+ goto out_unlock;
+
if (dev->parent)
pm_runtime_get_sync(dev->parent);
@@ -784,7 +992,7 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
if (dev->parent)
pm_runtime_put(dev->parent);
-
+out_unlock:
device_unlock(dev);
put_device(dev);
@@ -793,9 +1001,12 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
static int __device_attach(struct device *dev, bool allow_async)
{
int ret = 0;
+ bool async = false;
device_lock(dev);
- if (dev->driver) {
+ if (dev->p->dead) {
+ goto out_unlock;
+ } else if (dev->driver) {
if (device_is_bound(dev)) {
ret = 1;
goto out_unlock;
@@ -804,7 +1015,7 @@ static int __device_attach(struct device *dev, bool allow_async)
if (ret == 0)
ret = 1;
else {
- dev->driver = NULL;
+ device_set_driver(dev, NULL);
ret = 0;
}
} else {
@@ -829,7 +1040,7 @@ static int __device_attach(struct device *dev, bool allow_async)
*/
dev_dbg(dev, "scheduling asynchronous probe\n");
get_device(dev);
- async_schedule(__device_attach_async_helper, dev);
+ async = true;
} else {
pm_request_idle(dev);
}
@@ -839,6 +1050,8 @@ static int __device_attach(struct device *dev, bool allow_async)
}
out_unlock:
device_unlock(dev);
+ if (async)
+ async_schedule_dev(__device_attach_async_helper, dev);
return ret;
}
@@ -864,12 +1077,95 @@ EXPORT_SYMBOL_GPL(device_attach);
void device_initial_probe(struct device *dev)
{
- __device_attach(dev, true);
+ struct subsys_private *sp = bus_to_subsys(dev->bus);
+
+ if (!sp)
+ return;
+
+ if (sp->drivers_autoprobe)
+ __device_attach(dev, true);
+
+ subsys_put(sp);
+}
+
+/*
+ * __device_driver_lock - acquire locks needed to manipulate dev->drv
+ * @dev: Device we will update driver info for
+ * @parent: Parent device. Needed if the bus requires parent lock
+ *
+ * This function will take the required locks for manipulating dev->drv.
+ * Normally this will just be the @dev lock, but when called for a USB
+ * interface, @parent lock will be held as well.
+ */
+static void __device_driver_lock(struct device *dev, struct device *parent)
+{
+ if (parent && dev->bus->need_parent_lock)
+ device_lock(parent);
+ device_lock(dev);
+}
+
+/*
+ * __device_driver_unlock - release locks needed to manipulate dev->drv
+ * @dev: Device we will update driver info for
+ * @parent: Parent device. Needed if the bus requires parent lock
+ *
+ * This function will release the required locks for manipulating dev->drv.
+ * Normally this will just be the @dev lock, but when called for a
+ * USB interface, @parent lock will be released as well.
+ */
+static void __device_driver_unlock(struct device *dev, struct device *parent)
+{
+ device_unlock(dev);
+ if (parent && dev->bus->need_parent_lock)
+ device_unlock(parent);
+}
+
+/**
+ * device_driver_attach - attach a specific driver to a specific device
+ * @drv: Driver to attach
+ * @dev: Device to attach it to
+ *
+ * Manually attach driver to a device. Will acquire both @dev lock and
+ * @dev->parent lock if needed. Returns 0 on success, -ERR on failure.
+ */
+int device_driver_attach(const struct device_driver *drv, struct device *dev)
+{
+ int ret;
+
+ __device_driver_lock(dev, dev->parent);
+ ret = __driver_probe_device(drv, dev);
+ __device_driver_unlock(dev, dev->parent);
+
+ /* also return probe errors as normal negative errnos */
+ if (ret > 0)
+ ret = -ret;
+ if (ret == -EPROBE_DEFER)
+ return -EAGAIN;
+ return ret;
+}
+EXPORT_SYMBOL_GPL(device_driver_attach);
+
+static void __driver_attach_async_helper(void *_dev, async_cookie_t cookie)
+{
+ struct device *dev = _dev;
+ const struct device_driver *drv;
+ int ret;
+
+ __device_driver_lock(dev, dev->parent);
+ drv = dev->p->async_driver;
+ dev->p->async_driver = NULL;
+ ret = driver_probe_device(drv, dev);
+ __device_driver_unlock(dev, dev->parent);
+
+ dev_dbg(dev, "driver %s async attach completed: %d\n", drv->name, ret);
+
+ put_device(dev);
}
static int __driver_attach(struct device *dev, void *data)
{
- struct device_driver *drv = data;
+ const struct device_driver *drv = data;
+ bool async = false;
int ret;
/*
@@ -888,20 +1184,46 @@ static int __driver_attach(struct device *dev, void *data)
return 0;
} else if (ret == -EPROBE_DEFER) {
dev_dbg(dev, "Device match requests probe deferral\n");
+ dev->can_match = true;
driver_deferred_probe_add(dev);
+ /*
+ * Driver could not match with device, but may match with
+ * another device on the bus.
+ */
+ return 0;
} else if (ret < 0) {
- dev_dbg(dev, "Bus failed to match device: %d", ret);
- return ret;
+ dev_dbg(dev, "Bus failed to match device: %d\n", ret);
+ /*
+ * Driver could not match with device, but may match with
+ * another device on the bus.
+ */
+ return 0;
} /* ret > 0 means positive match */
- if (dev->parent && dev->bus->need_parent_lock)
- device_lock(dev->parent);
- device_lock(dev);
- if (!dev->driver)
- driver_probe_device(drv, dev);
- device_unlock(dev);
- if (dev->parent && dev->bus->need_parent_lock)
- device_unlock(dev->parent);
+ if (driver_allows_async_probing(drv)) {
+ /*
+ * Instead of probing the device synchronously we will
+ * probe it asynchronously to allow for more parallelism.
+ *
+ * We only take the device lock here in order to guarantee
+ * that the dev->driver and async_driver fields are protected
+ */
+ dev_dbg(dev, "probing driver %s asynchronously\n", drv->name);
+ device_lock(dev);
+ if (!dev->driver && !dev->p->async_driver) {
+ get_device(dev);
+ dev->p->async_driver = drv;
+ async = true;
+ }
+ device_unlock(dev);
+ if (async)
+ async_schedule_dev(__driver_attach_async_helper, dev);
+ return 0;
+ }
+
+ __device_driver_lock(dev, dev->parent);
+ driver_probe_device(drv, dev);
+ __device_driver_unlock(dev, dev->parent);
return 0;
}
@@ -915,9 +1237,10 @@ static int __driver_attach(struct device *dev, void *data)
* returns 0 and the @dev->driver is set, we've found a
* compatible pair.
*/
-int driver_attach(struct device_driver *drv)
+int driver_attach(const struct device_driver *drv)
{
- return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
+ /* The (void *) will be put back to const * in __driver_attach() */
+ return bus_for_each_dev(drv->bus, NULL, (void *)drv, __driver_attach);
}
EXPORT_SYMBOL_GPL(driver_attach);
@@ -931,78 +1254,57 @@ static void __device_release_driver(struct device *dev, struct device *parent)
drv = dev->driver;
if (drv) {
+ pm_runtime_get_sync(dev);
+
while (device_links_busy(dev)) {
- device_unlock(dev);
- if (parent && dev->bus->need_parent_lock)
- device_unlock(parent);
+ __device_driver_unlock(dev, parent);
device_links_unbind_consumers(dev);
- if (parent && dev->bus->need_parent_lock)
- device_lock(parent);
- device_lock(dev);
+ __device_driver_lock(dev, parent);
/*
* A concurrent invocation of the same function might
* have released the driver successfully while this one
* was waiting, so check for that.
*/
- if (dev->driver != drv)
+ if (dev->driver != drv) {
+ pm_runtime_put(dev);
return;
+ }
}
- pm_runtime_get_sync(dev);
- pm_runtime_clean_up_links(dev);
-
driver_sysfs_remove(dev);
- if (dev->bus)
- blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
- BUS_NOTIFY_UNBIND_DRIVER,
- dev);
+ bus_notify(dev, BUS_NOTIFY_UNBIND_DRIVER);
pm_runtime_put_sync(dev);
- if (dev->bus && dev->bus->remove)
- dev->bus->remove(dev);
- else if (drv->remove)
- drv->remove(dev);
+ device_remove(dev);
- device_links_driver_cleanup(dev);
- arch_teardown_dma_ops(dev);
+ if (dev->bus && dev->bus->dma_cleanup)
+ dev->bus->dma_cleanup(dev);
- devres_release_all(dev);
- dev->driver = NULL;
- dev_set_drvdata(dev, NULL);
- if (dev->pm_domain && dev->pm_domain->dismiss)
- dev->pm_domain->dismiss(dev);
- pm_runtime_reinit(dev);
- dev_pm_set_driver_flags(dev, 0);
+ device_unbind_cleanup(dev);
+ device_links_driver_cleanup(dev);
klist_remove(&dev->p->knode_driver);
device_pm_check_callbacks(dev);
- if (dev->bus)
- blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
- BUS_NOTIFY_UNBOUND_DRIVER,
- dev);
+ bus_notify(dev, BUS_NOTIFY_UNBOUND_DRIVER);
kobject_uevent(&dev->kobj, KOBJ_UNBIND);
}
}
void device_release_driver_internal(struct device *dev,
- struct device_driver *drv,
+ const struct device_driver *drv,
struct device *parent)
{
- if (parent && dev->bus->need_parent_lock)
- device_lock(parent);
+ __device_driver_lock(dev, parent);
- device_lock(dev);
if (!drv || drv == dev->driver)
__device_release_driver(dev, parent);
- device_unlock(dev);
- if (parent && dev->bus->need_parent_lock)
- device_unlock(parent);
+ __device_driver_unlock(dev, parent);
}
/**
@@ -1028,10 +1330,22 @@ void device_release_driver(struct device *dev)
EXPORT_SYMBOL_GPL(device_release_driver);
/**
+ * device_driver_detach - detach driver from a specific device
+ * @dev: device to detach driver from
+ *
+ * Detach driver from device. Will acquire both @dev lock and @dev->parent
+ * lock if needed.
+ */
+void device_driver_detach(struct device *dev)
+{
+ device_release_driver_internal(dev, NULL, dev->parent);
+}
+
+/**
* driver_detach - detach driver from all devices it controls.
* @drv: driver.
*/
-void driver_detach(struct device_driver *drv)
+void driver_detach(const struct device_driver *drv)
{
struct device_private *dev_prv;
struct device *dev;
@@ -1045,7 +1359,7 @@ void driver_detach(struct device_driver *drv)
spin_unlock(&drv->p->klist_devices.k_lock);
break;
}
- dev_prv = list_entry(drv->p->klist_devices.k_list.prev,
+ dev_prv = list_last_entry(&drv->p->klist_devices.k_list,
struct device_private,
knode_driver.n_node);
dev = dev_prv->device;