diff options
| author | Saravana Kannan <saravanak@google.com> | 2023-03-03 16:53:54 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-10 09:06:22 +0100 |
| commit | f8fb576658a3e19796e2e1a12a5ec8f44dac02b6 (patch) | |
| tree | 754eb365da8989ddeebdd90206ee61ef7f799246 | |
| parent | ffbe08a8e86d03513dc45b5389fab7f3477433b6 (diff) | |
driver core: Make state_synced device attribute writeable
If the file is written to and sync_state() hasn't been called for the
device yet, then call sync_state() for the device independent of the
state of its consumers.
This is useful for supplier devices that have one or more consumers that
don't have a driver but the consumers are in a state that don't use the
resources supplied by the supplier device.
This gives finer grained control than using the
fw_devlink.sync_state=timeout kernel commandline parameter.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20230304005355.746421-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-state_synced | 5 | ||||
| -rw-r--r-- | drivers/base/base.h | 8 | ||||
| -rw-r--r-- | drivers/base/core.c | 5 | ||||
| -rw-r--r-- | drivers/base/dd.c | 23 |
4 files changed, 36 insertions, 5 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-state_synced b/Documentation/ABI/testing/sysfs-devices-state_synced index 0c922d7d02fc..c64636ddac41 100644 --- a/Documentation/ABI/testing/sysfs-devices-state_synced +++ b/Documentation/ABI/testing/sysfs-devices-state_synced @@ -21,4 +21,9 @@ Description: at the time the kernel starts are not affected or limited in any way by sync_state() callbacks. + Writing "1" to this file will force a call to the device's + sync_state() function if it hasn't been called already. The + sync_state() call happens independent of the state of the + consumer devices. + diff --git a/drivers/base/base.h b/drivers/base/base.h index 6fcd71803d35..b055eba1ec30 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -164,6 +164,14 @@ static inline int driver_match_device(struct device_driver *drv, return drv->bus->match ? drv->bus->match(dev, drv) : 1; } +static inline void dev_sync_state(struct device *dev) +{ + if (dev->bus->sync_state) + dev->bus->sync_state(dev); + else if (dev->driver && dev->driver->sync_state) + dev->driver->sync_state(dev); +} + extern int driver_add_groups(struct device_driver *drv, const struct attribute_group **groups); extern void driver_remove_groups(struct device_driver *drv, diff --git a/drivers/base/core.c b/drivers/base/core.c index 871e6513a6c8..fe74a786e2c3 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1160,10 +1160,7 @@ static void device_links_flush_sync_list(struct list_head *list, if (dev != dont_lock_dev) device_lock(dev); - if (dev->bus->sync_state) - dev->bus->sync_state(dev); - else if (dev->driver && dev->driver->sync_state) - dev->driver->sync_state(dev); + dev_sync_state(dev); if (dev != dont_lock_dev) device_unlock(dev); diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 84f07e0050dd..7b9ab2050b84 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -510,6 +510,27 @@ EXPORT_SYMBOL_GPL(device_bind_driver); static atomic_t probe_count = ATOMIC_INIT(0); static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); +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) { @@ -521,7 +542,7 @@ static ssize_t state_synced_show(struct device *dev, return sysfs_emit(buf, "%u\n", val); } -static DEVICE_ATTR_RO(state_synced); +static DEVICE_ATTR_RW(state_synced); static void device_unbind_cleanup(struct device *dev) { |