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2020-11-10Merge tag 'v5.4.76' into 5.4-2.1.x-imxAndrey Zhizhikin
This is the 5.4.76 stable release Conflicts: - drivers/tty/serial/fsl_lpuart.c: Fix merge conflict of upstream patches [86875e1d6426] and [8febdfb5973d], which contradicted with patch [cde0cb39c0e8e] from NXP. Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com>
2020-11-10PM: runtime: Resume the device earlier in __device_release_driver()Rafael J. Wysocki
commit 9226c504e364158a17a68ff1fe9d67d266922f50 upstream. Since the device is resumed from runtime-suspend in __device_release_driver() anyway, it is better to do that before looking for busy managed device links from it to consumers, because if there are any, device_links_unbind_consumers() will be called and it will cause the consumer devices' drivers to unbind, so the consumer devices will be runtime-resumed. In turn, resuming each consumer device will cause the supplier to be resumed and when the runtime PM references from the given consumer to it are dropped, it may be suspended. Then, the runtime-resume of the next consumer will cause the supplier to resume again and so on. Update the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Fixes: 9ed9895370ae ("driver core: Functional dependencies tracking support") Cc: All applicable <stable@vger.kernel.org> # All applicable Tested-by: Xiang Chen <chenxiang66@hisilicon.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10PM: runtime: Drop pm_runtime_clean_up_links()Rafael J. Wysocki
commit d6e36668598154820177bfd78c1621d8e6c580a2 upstream. After commit d12544fb2aa9 ("PM: runtime: Remove link state checks in rpm_get/put_supplier()") nothing prevents the consumer device's runtime PM from acquiring additional references to the supplier device after pm_runtime_clean_up_links() has run (or even while it is running), so calling this function from __device_release_driver() may be pointless (or even harmful). Moreover, it ignores stateless device links, so the runtime PM handling of managed and stateless device links is inconsistent because of it, so better get rid of it entirely. Fixes: d12544fb2aa9 ("PM: runtime: Remove link state checks in rpm_get/put_supplier()") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+ Tested-by: Xiang Chen <chenxiang66@hisilicon.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-15Merge tag 'v5.4.71' into 5.4-2.1.x-imxAndrey Zhizhikin
This is the 5.4.71 stable release Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com>
2020-10-14driver core: Fix probe_count imbalance in really_probe()Tetsuo Handa
commit b292b50b0efcc7095d8bf15505fba6909bb35dce upstream. syzbot is reporting hung task in wait_for_device_probe() [1]. At least, we always need to decrement probe_count if we incremented probe_count in really_probe(). However, since I can't find "Resources present before probing" message in the console log, both "this message simply flowed off" and "syzbot is not hitting this path" will be possible. Therefore, while we are at it, let's also prepare for concurrent wait_for_device_probe() calls by replacing wake_up() with wake_up_all(). [1] https://syzkaller.appspot.com/bug?id=25c833f1983c9c1d512f4ff860dd0d7f5a2e2c0f Reported-by: syzbot <syzbot+805f5f6ae37411f15b64@syzkaller.appspotmail.com> Fixes: 7c35e699c88bd607 ("driver core: Print device when resources present in really_probe()") Cc: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20200713021254.3444-1-penguin-kernel@I-love.SAKURA.ne.jp [iwamatsu: Drop patch for deferred_probe_timeout_work_func()] Signed-off-by: Nobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu@toshiba.co.jp> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-24Merge tag 'v5.4.60' into 5.4-2.1.x-imxAndrey Zhizhikin
This is the 5.4.60 stable release Conflicts (manual resolve): - drivers/crypto/caam/caamalg.c Keep NXP version, as it already covers the functionality for the upstream patch [d6bbd4eea2439] - drivers/gpu/drm/imx/imx-ldb.c Merge patch [1752ab50e8256] from upstream to disable both LVDS channels when Enoder is disabled Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com>
2020-08-21driver core: Avoid binding drivers to dead devicesLukas Wunner
commit 654888327e9f655a9d55ad477a9583e90e8c9b5c upstream. Commit 3451a495ef24 ("driver core: Establish order of operations for device_add and device_del via bitflag") sought to prevent asynchronous driver binding to a device which is being removed. It added a per-device "dead" flag which is checked in the following code paths: * asynchronous binding in __driver_attach_async_helper() * synchronous binding in device_driver_attach() * asynchronous binding in __device_attach_async_helper() It did *not* check the flag upon: * synchronous binding in __device_attach() However __device_attach() may also be called asynchronously from: deferred_probe_work_func() bus_probe_device() device_initial_probe() __device_attach() So if the commit's intention was to check the "dead" flag in all asynchronous code paths, then a check is also necessary in __device_attach(). Add the missing check. Fixes: 3451a495ef24 ("driver core: Establish order of operations for device_add and device_del via bitflag") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v5.1+ Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Link: https://lore.kernel.org/r/de88a23a6fe0ef70f7cfd13c8aea9ab51b4edab6.1594214103.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-08Merge tag 'v5.4.24' into imx_5.4.yJason Liu
Merge Linux stable release v5.4.24 into imx_5.4.y * tag 'v5.4.24': (3306 commits) Linux 5.4.24 blktrace: Protect q->blk_trace with RCU kvm: nVMX: VMWRITE checks unsupported field before read-only field ... Signed-off-by: Jason Liu <jason.hui.liu@nxp.com> Conflicts: arch/arm/boot/dts/imx6sll-evk.dts arch/arm/boot/dts/imx7ulp.dtsi arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi drivers/clk/imx/clk-composite-8m.c drivers/gpio/gpio-mxc.c drivers/irqchip/Kconfig drivers/mmc/host/sdhci-of-esdhc.c drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c drivers/net/can/flexcan.c drivers/net/ethernet/freescale/dpaa/dpaa_eth.c drivers/net/ethernet/mscc/ocelot.c drivers/net/ethernet/stmicro/stmmac/stmmac_main.c drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c drivers/net/phy/realtek.c drivers/pci/controller/mobiveil/pcie-mobiveil-host.c drivers/perf/fsl_imx8_ddr_perf.c drivers/tee/optee/shm_pool.c drivers/usb/cdns3/gadget.c kernel/sched/cpufreq.c net/core/xdp.c sound/soc/fsl/fsl_esai.c sound/soc/fsl/fsl_sai.c sound/soc/sof/core.c sound/soc/sof/imx/Kconfig sound/soc/sof/loader.c
2020-02-24driver core: Print device when resources present in really_probe()Geert Uytterhoeven
[ Upstream commit 7c35e699c88bd60734277b26962783c60e04b494 ] If a device already has devres items attached before probing, a warning backtrace is printed. However, this backtrace does not reveal the offending device, leaving the user uninformed. Furthermore, using WARN_ON() causes systems with panic-on-warn to reboot. Fix this by replacing the WARN_ON() by a dev_crit() message. Abort probing the device, to prevent doing more damage to the device's resources. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20191206132219.28908-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-25drivers: base: move devices pm to tail when driver boundDong Aisheng
Only moving device pm to tail for defer probe is not enough because the device driver may be probed out of order without defer probe due to different driver init levels. Let's move the device pm to tail in the driver bound to ensure the device pm sequence is exactly the same as its probe sequence. Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
2019-08-27Revert "driver core: Add edit_links() callback for drivers"Greg Kroah-Hartman
This reverts commit 134b23eec9e3a3c795a6ceb0efe2fa63e87983b2. Based on a lot of email and in-person discussions, this patch series is being reworked to address a number of issues that were pointed out that needed to be taken care of before it should be merged. It will be resubmitted with those changes hopefully soon. Cc: Frank Rowand <frowand.list@gmail.com> Cc: Saravana Kannan <saravanak@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-02Merge tag 'dev_groups_all_drivers' into driver-core-nextGreg Kroah-Hartman
dev_groups added to struct driver Persistent tag for others to pull this branch from This is the first patch in a longer series that adds the ability for the driver core to create and remove a list of attribute groups automatically when the device is bound/unbound from a specific driver. See: https://lore.kernel.org/r/20190731124349.4474-2-gregkh@linuxfoundation.org for details on this patch, and examples of how to use it in other drivers. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-02driver core: add dev_groups to all driversDmitry Torokhov
Add the ability for the driver core to create and remove a list of attribute groups automatically when the device is bound/unbound from a specific driver. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Tested-by: Richard Gong <richard.gong@linux.intel.com> Link: https://lore.kernel.org/r/20190731124349.4474-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-01driver core: Add edit_links() callback for driversSaravana Kannan
The driver core/bus adding supplier-consumer dependencies by default enables functional dependencies to be tracked correctly even when the consumer devices haven't had their drivers registered or loaded (if they are modules). However, when the bus incorrectly adds dependencies that it shouldn't have added, the devices might never probe. For example, if device-C is a consumer of device-S and they have phandles to each other in DT, the following could happen: 1. Device-S get added first. 2. The bus add_links() callback will (incorrectly) try to link it as a consumer of device-C. 3. Since device-C isn't present, device-S will be put in "waiting-for-supplier" list. 4. Device-C gets added next. 5. All devices in "waiting-for-supplier" list are retried for linking. 6. Device-S gets linked as consumer to Device-C. 7. The bus add_links() callback will (correctly) try to link it as a consumer of device-S. 8. This isn't allowed because it would create a cyclic device links. Neither devices will get probed since the supplier is marked as dependent on the consumer. And the consumer will never probe because the consumer can't get resources from the supplier. Without this patch, things stay in this broken state. However, with this patch, the execution will continue like this: 9. Device-C's driver is loaded. 10. Device-C's driver removes Device-S as a consumer of Device-C. 11. Device-C's driver adds Device-C as a consumer of Device-S. 12. Device-S probes. 14. Device-C probes. kbuild test robot reported missing documentation for device.has_edit_links Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20190731221721.187713-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03driver: core: Allow subsystems to continue deferring probeThierry Reding
Some subsystems, such as pinctrl, allow continuing to defer probe indefinitely. This is useful for devices that depend on resources provided by devices that are only probed after the init stage. One example of this can be seen on Tegra, where the DPAUX hardware contains pinmuxing controls for pins that it shares with an I2C controller. The I2C controller is typically used for communication with a monitor over HDMI (DDC). However, other instances of the I2C controller are used to access system critical components, such as a PMIC. The I2C controller driver will therefore usually be a builtin driver, whereas the DPAUX driver is part of the display driver that is loaded from a module to avoid bloating the kernel image with all of the DRM/KMS subsystem. In this particular case the pins used by this I2C/DDC controller become accessible very late in the boot process. However, since the controller is only used in conjunction with display, that's not an issue. Unfortunately the driver core currently outputs a warning message when a device fails to get the pinctrl before the end of the init stage. That can be confusing for the user because it may sound like an unwanted error occurred, whereas it's really an expected and harmless situation. In order to eliminate this warning, this patch allows callers of the driver_deferred_probe_check_state() helper to specify that they want to continue deferring probe, regardless of whether we're past the init stage or not. All of the callers of that function are updated for the new signature, but only the pinctrl subsystem passes a true value in the new persist parameter if appropriate. Signed-off-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190621151725.20414-1-thierry.reding@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25driver core: Postpone DMA tear-down until after devres release for probe failureJohn Garry
In commit 376991db4b64 ("driver core: Postpone DMA tear-down until after devres release"), we changed the ordering of tearing down the device DMA ops and releasing all the device's resources; this was because the DMA ops should be maintained until we release the device's managed DMA memories. However, we have seen another crash on an arm64 system when a device driver probe fails: hisi_sas_v3_hw 0000:74:02.0: Adding to iommu group 2 scsi host1: hisi_sas_v3_hw BUG: Bad page state in process swapper/0 pfn:313f5 page:ffff7e0000c4fd40 count:1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfffe00000001000(reserved) raw: 0fffe00000001000 ffff7e0000c4fd48 ffff7e0000c4fd48 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set bad because of flags: 0x1000(reserved) Modules linked in: CPU: 49 PID: 1 Comm: swapper/0 Not tainted 5.1.0-rc1-43081-g22d97fd-dirty #1433 Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI RC0 - V1.12.01 01/29/2019 Call trace: dump_backtrace+0x0/0x118 show_stack+0x14/0x1c dump_stack+0xa4/0xc8 bad_page+0xe4/0x13c free_pages_check_bad+0x4c/0xc0 __free_pages_ok+0x30c/0x340 __free_pages+0x30/0x44 __dma_direct_free_pages+0x30/0x38 dma_direct_free+0x24/0x38 dma_free_attrs+0x9c/0xd8 dmam_release+0x20/0x28 release_nodes+0x17c/0x220 devres_release_all+0x34/0x54 really_probe+0xc4/0x2c8 driver_probe_device+0x58/0xfc device_driver_attach+0x68/0x70 __driver_attach+0x94/0xdc bus_for_each_dev+0x5c/0xb4 driver_attach+0x20/0x28 bus_add_driver+0x14c/0x200 driver_register+0x6c/0x124 __pci_register_driver+0x48/0x50 sas_v3_pci_driver_init+0x20/0x28 do_one_initcall+0x40/0x25c kernel_init_freeable+0x2b8/0x3c0 kernel_init+0x10/0x100 ret_from_fork+0x10/0x18 Disabling lock debugging due to kernel taint BUG: Bad page state in process swapper/0 pfn:313f6 page:ffff7e0000c4fd80 count:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 89.322983] flags: 0xfffe00000001000(reserved) raw: 0fffe00000001000 ffff7e0000c4fd88 ffff7e0000c4fd88 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 The crash occurs for the same reason. In this case, on the really_probe() failure path, we are still clearing the DMA ops prior to releasing the device's managed memories. This patch fixes this issue by reordering the DMA ops teardown and the call to devres_release_all() on the failure path. Reported-by: Xiang Chen <chenxiang66@hisilicon.com> Tested-by: Xiang Chen <chenxiang66@hisilicon.com> Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-14async: Add cmdline option to specify drivers to be async probedFeng Tang
Asynchronous driver probing can help much on kernel fastboot, and this option can provide a flexible way to optimize and quickly verify async driver probe. Also it will help in below cases: * Some driver actually covers several families of HWs, some of which could use async probing while others don't. So we can't simply turn on the PROBE_PREFER_ASYNCHRONOUS flag in driver, but use this cmdline option, like igb driver async patch discussed at https://www.spinics.net/lists/netdev/msg545986.html * For SOC (System on Chip) with multiple spi or i2c controllers, most of the slave spi/i2c devices will be assigned with fixed controller number, while async probing may make those controllers get different index for each boot, which prevents those controller drivers to be async probed. For platforms not using these spi/i2c slave devices, they can use this cmdline option to benefit from the async probing. Suggested-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-08driver core: Postpone DMA tear-down until after devres releaseGeert Uytterhoeven
When unbinding the (IOMMU-enabled) R-Car SATA device on Salvator-XS (R-Car H3 ES2.0), in preparation of rebinding against vfio-platform for device pass-through for virtualization:     echo ee300000.sata > /sys/bus/platform/drivers/sata_rcar/unbind the kernel crashes with:     Unable to handle kernel paging request at virtual address ffffffbf029ffffc     Mem abort info:       ESR = 0x96000006       Exception class = DABT (current EL), IL = 32 bits       SET = 0, FnV = 0       EA = 0, S1PTW = 0     Data abort info:       ISV = 0, ISS = 0x00000006       CM = 0, WnR = 0     swapper pgtable: 4k pages, 39-bit VAs, pgdp = 000000007e8c586c     [ffffffbf029ffffc] pgd=000000073bfc6003, pud=000000073bfc6003, pmd=0000000000000000     Internal error: Oops: 96000006 [#1] SMP     Modules linked in:     CPU: 0 PID: 1098 Comm: bash Not tainted 5.0.0-rc5-salvator-x-00452-g37596f884f4318ef #287     Hardware name: Renesas Salvator-X 2nd version board based on r8a7795 ES2.0+ (DT)     pstate: 60400005 (nZCv daif +PAN -UAO)     pc : __free_pages+0x8/0x58     lr : __dma_direct_free_pages+0x50/0x5c     sp : ffffff801268baa0     x29: ffffff801268baa0 x28: 0000000000000000     x27: ffffffc6f9c60bf0 x26: ffffffc6f9c60bf0     x25: ffffffc6f9c60810 x24: 0000000000000000     x23: 00000000fffff000 x22: ffffff8012145000     x21: 0000000000000800 x20: ffffffbf029fffc8     x19: 0000000000000000 x18: ffffffc6f86c42c8     x17: 0000000000000000 x16: 0000000000000070     x15: 0000000000000003 x14: 0000000000000000     x13: ffffff801103d7f8 x12: 0000000000000028     x11: ffffff8011117604 x10: 0000000000009ad8     x9 : ffffff80110126d0 x8 : ffffffc6f7563000     x7 : 6b6b6b6b6b6b6b6b x6 : 0000000000000018     x5 : ffffff8011cf3cc8 x4 : 0000000000004000     x3 : 0000000000080000 x2 : 0000000000000001     x1 : 0000000000000000 x0 : ffffffbf029fffc8     Process bash (pid: 1098, stack limit = 0x00000000c38e3e32)     Call trace:      __free_pages+0x8/0x58      __dma_direct_free_pages+0x50/0x5c      arch_dma_free+0x1c/0x98      dma_direct_free+0x14/0x24      dma_free_attrs+0x9c/0xdc      dmam_release+0x18/0x20      release_nodes+0x25c/0x28c      devres_release_all+0x48/0x4c      device_release_driver_internal+0x184/0x1f0      device_release_driver+0x14/0x1c      unbind_store+0x70/0xb8      drv_attr_store+0x24/0x34      sysfs_kf_write+0x4c/0x64      kernfs_fop_write+0x154/0x1c4      __vfs_write+0x34/0x164      vfs_write+0xb4/0x16c      ksys_write+0x5c/0xbc      __arm64_sys_write+0x14/0x1c      el0_svc_common+0x98/0x114      el0_svc_handler+0x1c/0x24      el0_svc+0x8/0xc     Code: d51b4234 17fffffa a9bf7bfd 910003fd (b9403404)     ---[ end trace 8c564cdd3a1a840f ]--- While I've bisected this to commit e8e683ae9a736407 ("iommu/of: Fix probe-deferral"), and reverting that commit on post-v5.0-rc4 kernels does fix the problem, this turned out to be a red herring. On arm64, arch_teardown_dma_ops() resets dev->dma_ops to NULL. Hence if a driver has used a managed DMA allocation API, the allocated DMA memory will be freed using the direct DMA ops, while it may have been allocated using a custom DMA ops (iommu_dma_ops in this case). Fix this by reversing the order of the calls to devres_release_all() and arch_teardown_dma_ops(). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable <stable@vger.kernel.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Add device link flag DL_FLAG_AUTOPROBE_CONSUMERRafael J. Wysocki
Add a new device link flag, DL_FLAG_AUTOPROBE_CONSUMER, to request the driver core to probe for a consumer driver automatically after binding a driver to the supplier device on a persistent managed device link. As unbinding the supplier driver on a managed device link causes the consumer driver to be detached from its device automatically, this flag provides a complementary mechanism which is needed to address some "composite device" use cases. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31driver core: Attach devices on CPU local to device nodeAlexander Duyck
Call the asynchronous probe routines on a CPU local to the device node. By doing this we should be able to improve our initialization time significantly as we can avoid having to access the device from a remote node which may introduce higher latency. For example, in the case of initializing memory for NVDIMM this can have a significant impact as initialing 3TB on remote node can take up to 39 seconds while initialing it on a local node only takes 23 seconds. It is situations like this where we will see the biggest improvement. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31driver core: Probe devices asynchronously instead of the driverAlexander Duyck
Probe devices asynchronously instead of the driver. This results in us seeing the same behavior if the device is registered before the driver or after. This way we can avoid serializing the initialization should the driver not be loaded until after the devices have already been added. The motivation behind this is that if we have a set of devices that take a significant amount of time to load we can greatly reduce the time to load by processing them in parallel instead of one at a time. In addition, each device can exist on a different node so placing a single thread on one CPU to initialize all of the devices for a given driver can result in poor performance on a system with multiple nodes. This approach can reduce the time needed to scan SCSI LUNs significantly. The only way to realize that speedup is by enabling more concurrency which is what is achieved with this patch. To achieve this it was necessary to add a new member "async_driver" to the device_private structure to store the driver pointer while we wait on the deferred probe call. Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31device core: Consolidate locking and unlocking of parent and deviceAlexander Duyck
Try to consolidate all of the locking and unlocking of both the parent and device when attaching or removing a driver from a given device. To do that I first consolidated the lock pattern into two functions __device_driver_lock and __device_driver_unlock. After doing that I then created functions specific to attaching and detaching the driver while acquiring these locks. By doing this I was able to reduce the number of spots where we touch need_parent_lock from 12 down to 4. This patch should produce no functional changes, it is meant to be a code clean-up/consolidation only. Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31driver core: Establish order of operations for device_add and device_del via ↵Alexander Duyck
bitflag Add an additional bit flag to the device_private struct named "dead". This additional flag provides a guarantee that when a device_del is executed on a given interface an async worker will not attempt to attach the driver following the earlier device_del call. Previously this guarantee was not present and could result in the device_del call attempting to remove a driver from an interface only to have the async worker attempt to probe the driver later when it finally completes the asynchronous probe call. One additional change added was that I pulled the check for dev->driver out of the __device_attach_driver call and instead placed it in the __device_attach_async_helper call. This was motivated by the fact that the only other caller of this, __device_attach, had already taken the device_lock() and checked for dev->driver. Instead of testing for this twice in this path it makes more sense to just consolidate the dev->dead and dev->driver checks together into one set of checks. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19driver core: Add missing dev->bus->need_parent_lock checksRafael J. Wysocki
__device_release_driver() has to check dev->bus->need_parent_lock before dropping the parent lock and acquiring it again as it may attempt to drop a lock that hasn't been acquired or lock a device that shouldn't be locked and create a lock imbalance. Fixes: 8c97a46af04b (driver core: hold dev's parent lock when needed) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable <stable@vger.kernel.org> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06driver core: Move async_synchronize_full callAlexander Duyck
Move the async_synchronize_full call out of __device_release_driver and into driver_detach. The idea behind this is that the async_synchronize_full call will only guarantee that any existing async operations are flushed. This doesn't do anything to guarantee that a hotplug event that may occur while we are doing the release of the driver will not be asynchronously scheduled. By moving this into the driver_detach path we can avoid potential deadlocks as we aren't holding the device lock at this point and we should not have the driver we want to flush loaded so the flush will take care of any asynchronous events the driver we are detaching might have scheduled. Fixes: 765230b5f084 ("driver-core: add asynchronous probing support for drivers") Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-11driver core: fix comments for device_block_probing()Randy Dunlap
Correct function name and spelling/typo for device_block_probing() in drivers/base/dd.c. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-11driver core: Replace simple_strtol by kstrtointMuchun Song
The simple_strtol() function is deprecated, use kstrtoint() instead. Signed-off-by: Muchun Song <smuchun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-08dma-mapping: remove dma_deconfigureChristoph Hellwig
This goes through a lot of hooks just to call arch_teardown_dma_ops. Replace it with a direct call instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-09-08dma-mapping: remove dma_configureChristoph Hellwig
There is no good reason for this indirection given that the method always exists. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-07-30Merge 4.18-rc7 into driver-core-nextGreg Kroah-Hartman
We need the driver core changes in here as well for testing. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-10driver core: Partially revert "driver core: correct device's shutdown order"Rafael J. Wysocki
Commit 52cdbdd49853 (driver core: correct device's shutdown order) introduced a regression by breaking device shutdown on some systems. Namely, the devices_kset_move_last() call in really_probe() added by that commit is a mistake as it may cause parents to follow children in the devices_kset list which then causes shutdown to fail. For example, if a device has children before really_probe() is called for it (which is not uncommon), that call will cause it to be reordered after the children in the devices_kset list and the ordering of that list will not reflect the correct device shutdown order any more. Also it causes the devices_kset list to be constantly reordered until all drivers have been probed which is totally pointless overhead in the majority of cases and it only covered an issue with system shutdown, while system-wide suspend/resume potentially had the same issue on the affected platforms (which was not covered). Moreover, the shutdown issue originally addressed by the change in really_probe() made by commit 52cdbdd49853 is not present in 4.18-rc any more, since dra7 started to use the sdhci-omap driver which doesn't disable any regulators during shutdown, so the really_probe() part of commit 52cdbdd49853 can be safely reverted. [The original issue was related to the omap_hsmmc driver used by dra7 previously.] For the above reasons, revert the really_probe() modifications made by commit 52cdbdd49853. The other code changes made by commit 52cdbdd49853 are useful and they need not be reverted. Fixes: 52cdbdd49853 (driver core: correct device's shutdown order) Link: https://lore.kernel.org/lkml/CAFgQCTt7VfqM=UyCnvNFxrSw8Z6cUtAi3HUwR4_xPAc03SgHjQ@mail.gmail.com/ Reported-by: Pingfan Liu <kernelfans@gmail.com> Tested-by: Pingfan Liu <kernelfans@gmail.com> Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-10driver core: allow stopping deferred probe after initRob Herring
Deferred probe will currently wait forever on dependent devices to probe, but sometimes a driver will never exist. It's also not always critical for a driver to exist. Platforms can rely on default configuration from the bootloader or reset defaults for things such as pinctrl and power domains. This is often the case with initial platform support until various drivers get enabled. There's at least 2 scenarios where deferred probe can render a platform broken. Both involve using a DT which has more devices and dependencies than the kernel supports. The 1st case is a driver may be disabled in the kernel config. The 2nd case is the kernel version may simply not have the dependent driver. This can happen if using a newer DT (provided by firmware perhaps) with a stable kernel version. Deferred probe issues can be difficult to debug especially if the console has dependencies or userspace fails to boot to a shell. There are also cases like IOMMUs where only built-in drivers are supported, so deferring probe after initcalls is not needed. The IOMMU subsystem implemented its own mechanism to handle this using OF_DECLARE linker sections. This commit adds makes ending deferred probe conditional on initcalls being completed or a debug timeout. Subsystems or drivers may opt-in by calling driver_deferred_probe_check_init_done() instead of unconditionally returning -EPROBE_DEFER. They may use additional information from DT or kernel's config to decide whether to continue to defer probe or not. The timeout mechanism is intended for debug purposes and WARNs loudly. The remaining deferred probe pending list will also be dumped after the timeout. Not that this timeout won't work for the console which needs to be enabled before userspace starts. However, if the console's dependencies are resolved, then the kernel log will be printed (as opposed to no output). Cc: Alexander Graf <agraf@suse.de> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-08driver core: add a debugfs entry to show deferred devicesJavier Martinez Canillas
With Device Trees (DT), the dependencies of the devices are defined in the DT, then the drivers parse that information to lookup the needed resources that have as dependencies. Since drivers and devices are registered in a non-deterministic way, it is possible that a device that is a dependency has not been registered yet by the time that is looked up. In this case the driver that requires this dependency cannot probe and has to defer it. So the driver core adds it to a list of deferred devices that is iterated again every time that a new driver is probed successfully. For debugging purposes it may be useful to know what are the devices whose probe function was deferred. Add a debugfs entry showing that information. $ cat /sys/kernel/debug/devices_deferred 48070000.i2c:twl@48:bci musb-hdrc.0.auto omapdrm.0 This information could be obtained partially by enabling debugging, but it means that the kernel log has to be parsed and the probe deferral balanced with the successes. This can be error probe and has to be done in a ad-hoc manner by everyone who needs to debug these kind of issues. Since the information is already known by the kernel, just show it to make it easier to debug. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-06drivers: base: initcall_debug logs for driver probe timesTodd Poynor
Add initcall_debug logs for each driver device probe call, for example: probe of a3800000.ramoops returned 1 after 3007 usecs This replaces the previous code added to report times for deferred probes. It also reports OF platform bus device creates that were formerly lumped together in a single entry for function of_platform_default_populate_init, as well as helping to annotate other initcalls that involve device probing. Remove restriction on printing probe times only during initcalls, since initcall_debug now continues to show driver timing info past the boot phase. Signed-off-by: Todd Poynor <toddpoynor@google.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-13Merge tag 'pm-4.18-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "These revert a recent PM core change that introduced a regression, fix the build when the recently added Kryo cpufreq driver is selected, add support for devices attached to multiple power domains to the generic power domains (genpd) framework, add support for iowait boosting on systens with hardware-managed P-states (HWP) enabled to the intel_pstate driver, modify the behavior of the wakeup_count device attribute in sysfs, fix a few issues and clean up some ugliness, mostly in cpufreq (core and drivers) and in the cpupower utility. Specifics: - Revert a recent PM core change that attempted to fix an issue related to device links, but introduced a regression (Rafael Wysocki) - Fix build when the recently added cpufreq driver for Kryo processors is selected by making it possible to build that driver as a module (Arnd Bergmann) - Fix the long idle detection mechanism in the out-of-band (ondemand and conservative) cpufreq governors (Chen Yu) - Add support for devices in multiple power domains to the generic power domains (genpd) framework (Ulf Hansson) - Add support for iowait boosting on systems with hardware-managed P-states (HWP) enabled to the intel_pstate driver and make it use that feature on systems with Skylake Xeon processors as it is reported to improve performance significantly on those systems (Srinivas Pandruvada) - Fix and update the acpi_cpufreq, ti-cpufreq and imx6q cpufreq drivers (Colin Ian King, Suman Anna, Sébastien Szymanski) - Change the behavior of the wakeup_count device attribute in sysfs to expose the number of events when the device might have aborted system suspend in progress (Ravi Chandra Sadineni) - Fix two minor issues in the cpupower utility (Abhishek Goel, Colin Ian King)" * tag 'pm-4.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: Revert "PM / runtime: Fixup reference counting of device link suppliers at probe" cpufreq: imx6q: check speed grades for i.MX6ULL cpufreq: governors: Fix long idle detection logic in load calculation cpufreq: intel_pstate: enable boost for Skylake Xeon PM / wakeup: Export wakeup_count instead of event_count via sysfs PM / Domains: Add dev_pm_domain_attach_by_id() to manage multi PM domains PM / Domains: Add support for multi PM domains per device to genpd PM / Domains: Split genpd_dev_pm_attach() PM / Domains: Don't attach devices in genpd with multi PM domains PM / Domains: dt: Allow power-domain property to be a list of specifiers cpufreq: intel_pstate: New sysfs entry to control HWP boost cpufreq: intel_pstate: HWP boost performance on IO wakeup cpufreq: intel_pstate: Add HWP boost utility and sched util hooks cpufreq: ti-cpufreq: Use devres managed API in probe() cpufreq: ti-cpufreq: Fix an incorrect error return value cpufreq: ACPI: make function acpi_cpufreq_fast_switch() static cpufreq: kryo: allow building as a loadable module cpupower : Fix header name to read idle state name cpupower: fix spelling mistake: "logilename" -> "logfilename"
2018-06-12Revert "PM / runtime: Fixup reference counting of device link suppliers at ↵Rafael J. Wysocki
probe" Revert commit 1e8378619841 (PM / runtime: Fixup reference counting of device link suppliers at probe), as it has introduced a regression and the condition it was designed to address should be covered by the existing code. Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-05Merge tag 'driver-core-4.18-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the driver core patchset for 4.18-rc1. The large chunk of these are firmware core documentation and api updates. Nothing major there, just better descriptions for others to be able to understand the firmware code better. There's also a user for a new firmware api call. Other than that, there are some minor updates for debugfs, kernfs, and the driver core itself. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits) driver core: hold dev's parent lock when needed driver-core: return EINVAL error instead of BUG_ON() driver core: add __printf verification to device_create_groups_vargs mm: memory_hotplug: use put_device() if device_register fail base: core: fix typo 'can by' to 'can be' debugfs: inode: debugfs_create_dir uses mode permission from parent debugfs: Re-use kstrtobool_from_user() Documentation: clarify firmware_class provenance and why we can't rename the module Documentation: remove stale firmware API reference Documentation: fix few typos and clarifications for the firmware loader ath10k: re-enable the firmware fallback mechanism for testmode ath10k: use firmware_request_nowarn() to load firmware firmware: add firmware_request_nowarn() - load firmware without warnings firmware_loader: make firmware_fallback_sysfs() print more useful firmware_loader: move kconfig FW_LOADER entries to its own file firmware_loader: replace ---help--- with help firmware_loader: enhance Kconfig documentation over FW_LOADER firmware_loader: document firmware_sysfs_fallback() firmware: rename fw_sysfs_fallback to firmware_fallback_sysfs() firmware: use () to terminate kernel-doc function names ...
2018-05-31driver core: hold dev's parent lock when neededMartin Liu
SoC have internal I/O buses that can't be proved for devices. The devices on the buses can be accessed directly without additinal configuration required. This type of bus is represented as "simple-bus". In some platforms, we name "soc" with "simple-bus" attribute and many devices are hooked under it described in DT (device tree). In commit bf74ad5bc417 ("Hold the device's parent's lock during probe and remove") to solve USB subsystem lock sequence since USB device's characteristic. Thus "soc" needs to be locked whenever a device and driver's probing happen under "soc" bus. During this period, an async driver tries to probe a device which is under the "soc" bus would be blocked until previous driver finish the probing and release "soc" lock. And the next probing under the "soc" bus need to wait for async finish. Because of that, driver's async probe for init time improvement will be shadowed. Since many devices don't have USB devices' characteristic, they actually don't need parent's lock. Thus, we introduce a lock flag in bus_type struct and driver core would lock the parent lock base on the flag. For USB, we set this flag in usb_bus_type to keep original lock behavior in driver core. Async probe could have more benefit after this patch. Signed-off-by: Martin Liu <liumartin@google.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-27PM / runtime: Fixup reference counting of device link suppliers at probeUlf Hansson
In the driver core, before it invokes really_probe() it runtime resumes the suppliers for the device via calling pm_runtime_get_suppliers(), which also increases the runtime PM usage count for each of the available supplier. This makes sense, as to be able to allow the consumer device to be probed by its driver. However, if the driver decides to add a new supplier link during ->probe(), hence updating the list of suppliers, the following call to pm_runtime_put_suppliers(), invoked after really_probe() in the driver core, we get into trouble. More precisely, pm_runtime_put() gets called also for the new supplier(s), which is wrong as the driver core, didn't trigger pm_runtime_get_sync() to be called for it in the first place. In other words, the new supplier may be runtime suspended even in cases when it shouldn't. Fix this behaviour, by runtime resume suppliers according to the same conditions as managed by the runtime PM core, when runtime resume callbacks are being invoked. Additionally, don't try to runtime suspend any of the suppliers after really_probe(), but instead rely on that to happen via the consumer device, when it becomes runtime suspended. Fixes: 21d5c57b3726 (PM / runtime: Use device links) Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-04-24PM / core: fix deferred probe breaking suspend resume orderFeng Kan
When bridge and its endpoint is enumerated the devices are added to the dpm list. Afterward, the bridge defers probe when IOMMU is not ready. This causes the bridge to be moved to the end of the dpm list when deferred probe kicks in. The order of the dpm list for bridge and endpoint is reversed. Add reordering code to move the bridge and its children and consumers to the end of the pm list so the order for suspend and resume is not altered. The code also move device and its children and consumers to the tail of device_kset list if it is registered. Signed-off-by: Toan Le <toanle@apm.com> Signed-off-by: Feng Kan <fkan@apm.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-03-23drivers: base: remove check for callback in coredump_store()Arend van Spriel
The check for the .coredump() callback in coredump_store() is redundant. It is already assured the device driver implements the callback upon creating the coredump sysfs entry. Signed-off-by: Arend van Spriel <aspriel@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-23drivers: base: add coredump driver opsArend van Spriel
This adds the coredump driver operation. When the driver defines it a coredump file is added in the sysfs folder of the device upon driver binding. The file is removed when the driver is unbound. User-space can trigger a coredump for this device by echo'ing to the coredump file. Signed-off-by: Arend van Spriel <aspriel@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-07driver core: Remove redundant license textGreg Kroah-Hartman
Now that the SPDX tag is in all driver core files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Johannes Berg <johannes@sipsolutions.net> Cc: "Luis R. Rodriguez" <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-07driver core: add SPDX identifiers to all driver core filesGreg Kroah-Hartman
It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the driver core files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Johannes Berg <johannes@sipsolutions.net> Cc: "Luis R. Rodriguez" <mcgrof@kernel.org> Cc: William Breathitt Gray <vilhelm.gray@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-16Merge tag 'driver-core-4.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of driver core / debugfs patches for 4.15-rc1. Not many here, mostly all are debugfs fixes to resolve some long-reported problems with files going away with references to them in userspace. There's also some SPDX cleanups for the debugfs code, as well as a few other minor driver core changes for issues reported by people. All of these have been in linux-next for a week or more with no reported issues" * tag 'driver-core-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: driver core: Fix device link deferred probe debugfs: Remove redundant license text debugfs: add SPDX identifiers to all debugfs files debugfs: defer debugfs_fsdata allocation to first usage debugfs: call debugfs_real_fops() only after debugfs_file_get() debugfs: purge obsolete SRCU based removal protection IB/hfi1: convert to debugfs_file_get() and -put() debugfs: convert to debugfs_file_get() and -put() debugfs: debugfs_real_fops(): drop __must_hold sparse annotation debugfs: implement per-file removal protection debugfs: add support for more elaborate ->d_fsdata driver core: Move device_links_purge() after bus_remove_device() arch_topology: Fix section miss match warning due to free_raw_capacity() driver-core: pr_err() strings should end with newlines
2017-11-08driver core: Fix device link deferred probeAdrian Hunter
A device probe deferred because of a device link is never probed again because it is not added to the deferred_probe_pending_list. Add it, taking care of the race with driver_deferred_probe_trigger(). Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-06PM / core: Add NEVER_SKIP and SMART_PREPARE driver flagsRafael J. Wysocki
The motivation for this change is to provide a way to work around a problem with the direct-complete mechanism used for avoiding system suspend/resume handling for devices in runtime suspend. The problem is that some middle layer code (the PCI bus type and the ACPI PM domain in particular) returns positive values from its system suspend ->prepare callbacks regardless of whether the driver's ->prepare returns a positive value or 0, which effectively prevents drivers from being able to control the direct-complete feature. Some drivers need that control, however, and the PCI bus type has grown its own flag to deal with this issue, but since it is not limited to PCI, it is better to address it by adding driver flags at the core level. To that end, add a driver_flags field to struct dev_pm_info for flags that can be set by device drivers at the probe time to inform the PM core and/or bus types, PM domains and so on on the capabilities and/or preferences of device drivers. Also add two static inline helpers for setting that field and testing it against a given set of flags and make the driver core clear it automatically on driver remove and probe failures. Define and document two PM driver flags related to the direct- complete feature: NEVER_SKIP and SMART_PREPARE that can be used, respectively, to indicate to the PM core that the direct-complete mechanism should never be used for the device and to inform the middle layer code (bus types, PM domains etc) that it can only request the PM core to use the direct-complete mechanism for the device (by returning a positive value from its ->prepare callback) if it also has been requested by the driver. While at it, make the core check pm_runtime_suspended() when setting power.direct_complete so that it doesn't need to be checked by ->prepare callbacks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-08-03initcall_debug: add deferred probe timesTodd Poynor
initcall_debug attributes all deferred device probe retries for the late_initcall level to function deferred_probe_initcall. Add logs of the individual device probe routines called, to identify which drivers are executing for how long during the initcall path. Deferred probes that occur after initcall processing are not shown. Example log messages added: [ 0.505119] deferred probe my-sound-device @ 6 [ 0.517656] deferred probe my-sound-device returned after 1227 usecs Signed-off-by: Todd Poynor <toddpoynor@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-22driver core: emit uevents when device is bound to a driverDmitry Torokhov
There are certain touch controllers that may come up in either normal (application) or boot mode, depending on whether firmware/configuration is corrupted when they are powered on. In boot mode the kernel does not create input device instance (because it does not necessarily know the characteristics of the input device in question). Another number of controllers does not store firmware in a non-volatile memory, and they similarly need to have firmware loaded before input device instance is created. There are also other types of devices with similar behavior. There is a desire to be able to trigger firmware loading via udev, but it has to happen only when driver is bound to a physical device (i2c or spi). These udev actions can not use ADD events, as those happen too early, so we are introducing BIND and UNBIND events that are emitted at the right moment. Also, many drivers create additional driver-specific device attributes when binding to the device, to provide userspace with additional controls. The new events allow userspace to adjust these driver-specific attributes without worrying that they are not there yet. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-20of/acpi: Configure dma operations at probe time for platform/amba/pci bus ↵Sricharan R
devices Configuring DMA ops at probe time will allow deferring device probe when the IOMMU isn't available yet. The dma_configure for the device is now called from the generic device_attach callback just before the bus/driver probe is called. This way, configuring the DMA ops for the device would be called at the same place for all bus_types, hence the deferred probing mechanism should work for all buses as well. pci_bus_add_devices (platform/amba)(_device_create/driver_register) | | pci_bus_add_device (device_add/driver_register) | | device_attach device_initial_probe | | __device_attach_driver __device_attach_driver | driver_probe_device | really_probe | dma_configure Similarly on the device/driver_unregister path __device_release_driver is called which inturn calls dma_deconfigure. This patch changes the dma ops configuration to probe time for both OF and ACPI based platform/amba/pci bus devices. Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci part) Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sricharan R <sricharan@codeaurora.org> Signed-off-by: Joerg Roedel <jroedel@suse.de>