From 4a7cc831670550e6b48ef5760e7213f89935ff0d Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Thu, 9 Jul 2015 16:00:44 +0800 Subject: genirq/MSI: Move msi_list from struct pci_dev to struct device Move msi_list from struct pci_dev into struct device, so we can support non-PCI-device based generic MSI interrupts. msi_list is now conditional under CONFIG_GENERIC_MSI_IRQ, which is selected from CONFIG_PCI_MSI, so no functional change for PCI MSI users. Signed-off-by: Jiang Liu Reviewed-by: Yijing Wang Acked-by: Bjorn Helgaas Cc: Tony Luck Cc: linux-arm-kernel@lists.infradead.org Cc: Grant Likely Cc: Marc Zyngier Cc: Stuart Yoder Cc: Borislav Petkov Cc: Greg Kroah-Hartman Cc: Joe Perches Cc: Dmitry Torokhov Cc: Paul Gortmaker Cc: Luis R. Rodriguez Cc: Rafael J. Wysocki Cc: Joerg Roedel Cc: Alexander Gordeev Link: http://lkml.kernel.org/r/1436428847-8886-10-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner --- drivers/base/core.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index dafae6d2f7ac..18e2a89aa138 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -662,6 +662,9 @@ void device_initialize(struct device *dev) INIT_LIST_HEAD(&dev->devres_head); device_pm_init(dev); set_dev_node(dev, -1); +#ifdef CONFIG_GENERIC_MSI_IRQ + INIT_LIST_HEAD(&dev->msi_list); +#endif } EXPORT_SYMBOL_GPL(device_initialize); -- cgit v1.2.3 From 3d060aeb72113cda0acf906bfe26914fc689506a Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Mon, 27 Jul 2015 18:04:00 +0300 Subject: driver core: implement device_for_each_child_reverse() The new function device_for_each_child_reverse() is helpful to traverse the registered devices in a reversed order, e.g. in the case when an operation on each device should be done first on the last added device, then on one before last and so on. Signed-off-by: Andy Shevchenko Acked-by: Greg Kroah-Hartman Signed-off-by: Lee Jones --- drivers/base/core.c | 43 +++++++++++++++++++++++++++++++++++++++++++ include/linux/device.h | 2 ++ 2 files changed, 45 insertions(+) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index dafae6d2f7ac..7d6279554afc 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1252,6 +1252,19 @@ void device_unregister(struct device *dev) } EXPORT_SYMBOL_GPL(device_unregister); +static struct device *prev_device(struct klist_iter *i) +{ + struct klist_node *n = klist_prev(i); + struct device *dev = NULL; + struct device_private *p; + + if (n) { + p = to_device_private_parent(n); + dev = p->device; + } + return dev; +} + static struct device *next_device(struct klist_iter *i) { struct klist_node *n = klist_next(i); @@ -1340,6 +1353,36 @@ int device_for_each_child(struct device *parent, void *data, } EXPORT_SYMBOL_GPL(device_for_each_child); +/** + * device_for_each_child_reverse - device child iterator in reversed order. + * @parent: parent struct device. + * @fn: function to be called for each device. + * @data: data for the callback. + * + * Iterate over @parent's child devices, and call @fn for each, + * passing it @data. + * + * We check the return of @fn each time. If it returns anything + * other than 0, we break out and return that value. + */ +int device_for_each_child_reverse(struct device *parent, void *data, + int (*fn)(struct device *dev, void *data)) +{ + struct klist_iter i; + struct device *child; + int error = 0; + + if (!parent->p) + return 0; + + klist_iter_init(&parent->p->klist_children, &i); + while ((child = prev_device(&i)) && !error) + error = fn(child, data); + klist_iter_exit(&i); + return error; +} +EXPORT_SYMBOL_GPL(device_for_each_child_reverse); + /** * device_find_child - device iterator for locating a particular device. * @parent: parent struct device diff --git a/include/linux/device.h b/include/linux/device.h index 5a31bf3a4024..af6fbc35d8a6 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -958,6 +958,8 @@ extern int __must_check device_add(struct device *dev); extern void device_del(struct device *dev); extern int device_for_each_child(struct device *dev, void *data, int (*fn)(struct device *dev, void *data)); +extern int device_for_each_child_reverse(struct device *dev, void *data, + int (*fn)(struct device *dev, void *data)); extern struct device *device_find_child(struct device *dev, void *data, int (*match)(struct device *dev, void *data)); extern int device_rename(struct device *dev, const char *new_name); -- cgit v1.2.3 From 52cdbdd49853dfa856082edb0f4c4c0249d9df07 Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Mon, 27 Jul 2015 20:43:01 +0300 Subject: driver core: correct device's shutdown order Now device's shutdown sequence is performed in reverse order of their registration in devices_kset list and this sequence corresponds to the reverse device's creation order. So, devices_kset data tracks "parent<-child" device's dependencies only. Unfortunately, that's not enough and causes problems in case of implementing board's specific shutdown procedures. For example [1]: "DRA7XX_evm uses PCF8575 and one of the PCF output lines feeds to MMC/SD and this line should be driven high in order for the MMC/SD to be detected. This line is modelled as regulator and the hsmmc driver takes care of enabling and disabling it. In the case of 'reboot', during shutdown path as part of it's cleanup process the hsmmc driver disables this regulator. This makes MMC boot not functional." To handle this issue the .shutdown() callback could be implemented for PCF8575 device where corresponding GPIO pins will be configured to states, required for correct warm/cold reset. This can be achieved only when all .shutdown() callbacks have been called already for all PCF8575's consumers. But devices_kset is not filled correctly now: devices_kset: Device61 4e000000.dmm devices_kset: Device62 48070000.i2c devices_kset: Device63 48072000.i2c devices_kset: Device64 48060000.i2c devices_kset: Device65 4809c000.mmc ... devices_kset: Device102 fixedregulator-sd ... devices_kset: Device181 0-0020 // PCF8575 devices_kset: Device182 gpiochip496 devices_kset: Device183 0-0021 // PCF8575 devices_kset: Device184 gpiochip480 As can be seen from above .shutdown() callback for PCF8575 will be called before its consumers, which, in turn means, that any changes of PCF8575 GPIO's pins will be or unsafe or overwritten later by GPIO's consumers. The problem can be solved if devices_kset list will be filled not only according device creation order, but also according device's probing order to track "supplier<-consumer" dependencies also. Hence, as a fix, lets add devices_kset_move_last(), devices_kset_move_before(), devices_kset_move_after() and call them from device_move() and also add call of devices_kset_move_last() in really_probe(). After this change all entries in devices_kset will be sorted according to device's creation ("parent<-child") and probing ("supplier<-consumer") order. devices_kset after: devices_kset: Device121 48070000.i2c devices_kset: Device122 i2c-0 ... devices_kset: Device147 regulator.24 devices_kset: Device148 0-0020 devices_kset: Device149 gpiochip496 devices_kset: Device150 0-0021 devices_kset: Device151 gpiochip480 devices_kset: Device152 0-0019 ... devices_kset: Device372 fixedregulator-sd devices_kset: Device373 regulator.29 devices_kset: Device374 4809c000.mmc devices_kset: Device375 mmc0 [1] http://www.spinics.net/lists/linux-mmc/msg29825.html Cc: Sekhar Nori Signed-off-by: Grygorii Strashko Signed-off-by: Greg Kroah-Hartman --- drivers/base/base.h | 1 + drivers/base/core.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ drivers/base/dd.c | 8 ++++++++ 3 files changed, 58 insertions(+) (limited to 'drivers/base/core.c') diff --git a/drivers/base/base.h b/drivers/base/base.h index 29c985eb9f4c..1782f3aa386e 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -134,6 +134,7 @@ extern int devres_release_all(struct device *dev); /* /sys/devices directory */ extern struct kset *devices_kset; +extern void devices_kset_move_last(struct device *dev); #if defined(CONFIG_MODULES) && defined(CONFIG_SYSFS) extern void module_add_driver(struct module *mod, struct device_driver *drv); diff --git a/drivers/base/core.c b/drivers/base/core.c index dafae6d2f7ac..fc5a558f62f9 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -533,6 +533,52 @@ static DEVICE_ATTR_RO(dev); /* /sys/devices/ */ struct kset *devices_kset; +/** + * devices_kset_move_before - Move device in the devices_kset's list. + * @deva: Device to move. + * @devb: Device @deva should come before. + */ +static void devices_kset_move_before(struct device *deva, struct device *devb) +{ + if (!devices_kset) + return; + pr_debug("devices_kset: Moving %s before %s\n", + dev_name(deva), dev_name(devb)); + spin_lock(&devices_kset->list_lock); + list_move_tail(&deva->kobj.entry, &devb->kobj.entry); + spin_unlock(&devices_kset->list_lock); +} + +/** + * devices_kset_move_after - Move device in the devices_kset's list. + * @deva: Device to move + * @devb: Device @deva should come after. + */ +static void devices_kset_move_after(struct device *deva, struct device *devb) +{ + if (!devices_kset) + return; + pr_debug("devices_kset: Moving %s after %s\n", + dev_name(deva), dev_name(devb)); + spin_lock(&devices_kset->list_lock); + list_move(&deva->kobj.entry, &devb->kobj.entry); + spin_unlock(&devices_kset->list_lock); +} + +/** + * devices_kset_move_last - move the device to the end of devices_kset's list. + * @dev: device to move + */ +void devices_kset_move_last(struct device *dev) +{ + if (!devices_kset) + return; + pr_debug("devices_kset: Moving %s to end of list\n", dev_name(dev)); + spin_lock(&devices_kset->list_lock); + list_move_tail(&dev->kobj.entry, &devices_kset->list); + spin_unlock(&devices_kset->list_lock); +} + /** * device_create_file - create sysfs attribute file for device. * @dev: device. @@ -1923,12 +1969,15 @@ int device_move(struct device *dev, struct device *new_parent, break; case DPM_ORDER_DEV_AFTER_PARENT: device_pm_move_after(dev, new_parent); + devices_kset_move_after(dev, new_parent); break; case DPM_ORDER_PARENT_BEFORE_DEV: device_pm_move_before(new_parent, dev); + devices_kset_move_before(new_parent, dev); break; case DPM_ORDER_DEV_LAST: device_pm_move_last(dev); + devices_kset_move_last(dev); break; } diff --git a/drivers/base/dd.c b/drivers/base/dd.c index a638bbb1a27a..cc2b1d4801fd 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -304,6 +304,14 @@ static int really_probe(struct device *dev, struct device_driver *drv) goto probe_failed; } + /* + * Ensure devices are listed in devices_kset in correct order + * It's important to move Dev to the end of devices_kset before + * calling .probe, because it could be recursive and parent Dev + * should always go first + */ + devices_kset_move_last(dev); + if (dev->bus->probe) { ret = dev->bus->probe(dev); if (ret) -- cgit v1.2.3