linux/drivers/base, branch v3.9

regmap: Back out work buffer fix

2013-04-09T17:03:25Z

This reverts commit bc8ce4 (regmap: don't corrupt work buffer in _regmap_raw_write()) since it turns out that it can cause issues when taken in isolation from the other changes in -next that lead to its discovery. On the basis that nobody noticed the problems for quite some time without that subsequent work let's drop it from v3.9. Signed-off-by: Mark Brown

Merge tag 'pm+acpi-3.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2013-04-04T22:56:28Z

Pull ACPI and power management fixes from Rafael Wysocki: - Revert of a recent cpuidle change that caused Nehalem machines to hang on boot from Alex Shi. - USB power management fix addressing a crash in the port device object's release routine from Rafael J Wysocki. - Device PM QoS fix for a potential deadlock related to sysfs interface from Rafael J Wysocki. - Fix for a cpufreq crash when the /cpus Device Tree node is missing from Paolo Pisati. - Fix for a build issue on ia64 related to the Boot Graphics Resource Table (BGRT) from Tony Luck. - Two fixes for ACPI handles being set incorrectly for device objects that don't correspond to any ACPI namespace nodes in the I2C and SPI subsystems from Rafael J Wysocki. - Fix for compiler warnings related to CONFIG_PM_DEVFREQ being unset from Rajagopal Venkat. - Fix for a symbol definition typo in cpufreq_governor.h from Borislav Petkov. * tag 'pm+acpi-3.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI / BGRT: Don't let users configure BGRT on non X86 systems cpuidle / ACPI: recover percpu ACPI processor cstate ACPI / I2C: Use parent's ACPI_HANDLE() in acpi_i2c_register_devices() cpufreq: Correct header guards typo ACPI / SPI: Use parent's ACPI_HANDLE() in acpi_register_spi_devices() cpufreq: check OF node /cpus presence before dereferencing it PM / devfreq: Fix compiler warnings for CONFIG_PM_DEVFREQ unset PM / QoS: Avoid possible deadlock related to sysfs access USB / PM: Don't try to hide PM QoS flags from usb_port_device_release()

PM / QoS: Avoid possible deadlock related to sysfs access

2013-04-01T23:25:24Z

Commit b81ea1b (PM / QoS: Fix concurrency issues and memory leaks in device PM QoS) put calls to pm_qos_sysfs_add_latency(), pm_qos_sysfs_add_flags(), pm_qos_sysfs_remove_latency(), and pm_qos_sysfs_remove_flags() under dev_pm_qos_mtx, which was a mistake, because it may lead to deadlocks in some situations. For example, if pm_qos_remote_wakeup_store() is run in parallel with dev_pm_qos_constraints_destroy(), they may deadlock in the following way: ====================================================== [ INFO: possible circular locking dependency detected ] 3.9.0-rc4-next-20130328-sasha-00014-g91a3267 #319 Tainted: G W ------------------------------------------------------- trinity-child6/12371 is trying to acquire lock: (s_active#54){++++.+}, at: [] sysfs_addrm_finish+0x31/0x60 but task is already holding lock: (dev_pm_qos_mtx){+.+.+.}, at: [] dev_pm_qos_constraints_destroy+0x23/0x250 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (dev_pm_qos_mtx){+.+.+.}: [] lock_acquire+0x1aa/0x240 [] __mutex_lock_common+0x59/0x5e0 [] mutex_lock_nested+0x3f/0x50 [] dev_pm_qos_update_flags+0x3f/0xc0 [] pm_qos_remote_wakeup_store+0x3f/0x70 [] dev_attr_store+0x13/0x20 [] sysfs_write_file+0xfa/0x150 [] __kernel_write+0x81/0x150 [] write_pipe_buf+0x4d/0x80 [] splice_from_pipe_feed+0x7c/0x120 [] __splice_from_pipe+0x45/0x80 [] splice_from_pipe+0x4c/0x70 [] default_file_splice_write+0x18/0x30 [] do_splice_from+0x83/0xb0 [] direct_splice_actor+0x1e/0x20 [] splice_direct_to_actor+0xe7/0x200 [] do_splice_direct+0x4c/0x70 [] do_sendfile+0x169/0x300 [] SyS_sendfile64+0x64/0xb0 [] tracesys+0xe1/0xe6 -> #0 (s_active#54){++++.+}: [] __lock_acquire+0x15bf/0x1e50 [] lock_acquire+0x1aa/0x240 [] sysfs_deactivate+0x122/0x1a0 [] sysfs_addrm_finish+0x31/0x60 [] sysfs_hash_and_remove+0x7f/0xb0 [] sysfs_unmerge_group+0x51/0x70 [] pm_qos_sysfs_remove_flags+0x14/0x20 [] __dev_pm_qos_hide_flags+0x30/0x70 [] dev_pm_qos_constraints_destroy+0x35/0x250 [] dpm_sysfs_remove+0x11/0x50 [] device_del+0x3f/0x1b0 [] device_unregister+0x48/0x60 [] usb_hub_remove_port_device+0x1c/0x20 [] hub_disconnect+0xdd/0x160 [] usb_unbind_interface+0x67/0x170 [] __device_release_driver+0x87/0xe0 [] device_release_driver+0x29/0x40 [] bus_remove_device+0x148/0x160 [] device_del+0x14f/0x1b0 [] usb_disable_device+0xf9/0x280 [] usb_set_configuration+0x268/0x840 [] usb_remove_store+0x4c/0x80 [] dev_attr_store+0x13/0x20 [] sysfs_write_file+0xfa/0x150 [] do_loop_readv_writev+0x4d/0x90 [] do_readv_writev+0xf9/0x1e0 [] vfs_writev+0x3a/0x60 [] SyS_writev+0x50/0xd0 [] tracesys+0xe1/0xe6 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(dev_pm_qos_mtx); lock(s_active#54); lock(dev_pm_qos_mtx); lock(s_active#54); *** DEADLOCK *** To avoid that, remove the calls to functions mentioned above from under dev_pm_qos_mtx and introduce a separate lock to prevent races between functions that add or remove device PM QoS sysfs attributes from happening. Reported-by: Sasha Levin Signed-off-by: Rafael J. Wysocki

Merge remote-tracking branch 'regmap/fix/async' into tmp

2013-03-31T22:27:38Z

Merge remote-tracking branch 'regmap/fix/core' into tmp

2013-03-31T22:09:22Z

regmap: async: Add missing return

2013-03-27T13:08:44Z

Let's only write once... Signed-off-by: Mark Brown

regmap: don't corrupt work buffer in _regmap_raw_write()

2013-03-21T19:08:15Z

_regmap_raw_write() contains code to call regcache_write() to write values to the cache. That code calls memcpy() to copy the value data to the start of the work_buf. However, at least when _regmap_raw_write() is called from _regmap_bus_raw_write(), the value data is in the work_buf, and this memcpy() operation may over-write part of that value data, depending on the value of reg_bytes + pad_bytes. At least when using reg_bytes==1 and pad_bytes==0, corruption of the value data does occur. To solve this, remove the memcpy() operation, and modify the subsequent .parse_val() call to parse the original value buffer directly. At least in the case of 8-bit register address and 16-bit values, and writes of single registers at a time, this memcpy-then-parse combination used to cancel each-other out; for a work-buffer containing xx 89 03, the memcpy changed it to 89 03 03, and the parse_val changed it back to 89 89 03, thus leaving the value uncorrupted. This appears completely accidental though. Since commit 8a819ff "regmap: core: Split out in place value parsing", .parse_val only returns the parsed value, and does not modify the buffer, and hence does not (accidentally) undo the corruption caused by memcpy(). This caused bogus values to get written to HW, thus preventing e.g. audio playback on systems with a WM8903 CODEC. This patch fixes that. Signed-off-by: Stephen Warren Signed-off-by: Mark Brown

regmap: cache Fix regcache-rbtree sync

2013-03-13T19:07:19Z

The last register block, which falls into the specified range, is not handled correctly. The formula which calculates the number of register which should be synced is inverse (and off by one). E.g. if all registers in that block should be synced only one is synced, and if only one should be synced all (but one) are synced. To calculate the number of registers that need to be synced we need to subtract the number of the first register in the block from the max register number and add one. This patch updates the code accordingly. The issue was introduced in commit ac8d91c ("regmap: Supply ranges to the sync operations"). Signed-off-by: Lars-Peter Clausen Signed-off-by: Mark Brown Cc: stable@vger.kernel.org

regmap: Initialize `map->debugfs' before regcache

2013-03-12T18:25:10Z

In the rbtree code we are exposing statistics relating to the number of nodes/registers of the rbtree cache for each of the devices. Ensure that `map->debugfs' has been initialized before we attempt to initialize the debugfs entry for the rbtree cache. Signed-off-by: Dimitris Papastamos Signed-off-by: Mark Brown Cc: stable@vger.kernel.org

Merge tag 'pm+acpi-3.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2013-03-07T22:54:28Z

Pull ACPI and power management fixes from Rafael J Wysocki: - Two fixes for the new intel_pstate driver from Dirk Brandewie. - Fix for incorrect usage of the .find_bridge() callback from struct acpi_bus_type in the USB core and subsequent removal of that callback from Rafael J Wysocki. - ACPI processor driver cleanups from Chen Gang and Syam Sidhardhan. - ACPI initialization and error messages fix from Joe Perches. - Operating Performance Points documentation improvement from Nishanth Menon. - Fixes for memory leaks and potential concurrency issues and sysfs attributes leaks during device removal in the core device PM QoS code from Rafael J Wysocki. - Calxeda Highbank cpufreq driver simplification from Emilio López. - cpufreq comment cleanup from Namhyung Kim. - Fix for a section mismatch in Calxeda Highbank interprocessor communication code from Mark Langsdorf (this is not a PM fix strictly speaking, but the code in question went in through the PM tree). * tag 'pm+acpi-3.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq / intel_pstate: Do not load on VM that does not report max P state. cpufreq / intel_pstate: Fix intel_pstate_init() error path ACPI / glue: Drop .find_bridge() callback from struct acpi_bus_type ACPI / glue: Add .match() callback to struct acpi_bus_type ACPI / porocessor: Beautify code, pr->id is u32 which is never < 0 ACPI / processor: Remove redundant NULL check before kfree ACPI / Sleep: Avoid interleaved message on errors PM / QoS: Remove device PM QoS sysfs attributes at the right place PM / QoS: Fix concurrency issues and memory leaks in device PM QoS cpufreq: highbank: do not initialize array with a loop PM / OPP: improve introductory documentation cpufreq: Fix a typo in comment mailbox, pl320-ipc: remove __init from probe function