Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices: OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
Find a file
Jon Hunter 8ebf15e9c8 i2c: tegra: Move suspend handling to NOIRQ phase
Commit acc8abcb2a ("i2c: tegra: Add suspend-resume support") added
suspend support for the Tegra I2C driver and following this change on
Tegra30 the following WARNING is seen on entering suspend ...

 WARNING: CPU: 2 PID: 689 at /dvs/git/dirty/git-master_l4t-upstream/kernel/drivers/i2c/i2c-core.h:54 __i2c_transfer+0x35c/0x70c
 i2c i2c-4: Transfer while suspended
 Modules linked in: brcmfmac brcmutil
 CPU: 2 PID: 689 Comm: rtcwake Not tainted 5.3.0-rc7-g089cf7f6ecb2 #1
 Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
 [<c0112264>] (unwind_backtrace) from [<c010ca94>] (show_stack+0x10/0x14)
 [<c010ca94>] (show_stack) from [<c0a77024>] (dump_stack+0xb4/0xc8)
 [<c0a77024>] (dump_stack) from [<c0124198>] (__warn+0xe0/0xf8)
 [<c0124198>] (__warn) from [<c01241f8>] (warn_slowpath_fmt+0x48/0x6c)
 [<c01241f8>] (warn_slowpath_fmt) from [<c06f6c40>] (__i2c_transfer+0x35c/0x70c)
 [<c06f6c40>] (__i2c_transfer) from [<c06f7048>] (i2c_transfer+0x58/0xf4)
 [<c06f7048>] (i2c_transfer) from [<c06f7130>] (i2c_transfer_buffer_flags+0x4c/0x70)
 [<c06f7130>] (i2c_transfer_buffer_flags) from [<c05bee78>] (regmap_i2c_write+0x14/0x30)
 [<c05bee78>] (regmap_i2c_write) from [<c05b9cac>] (_regmap_raw_write_impl+0x35c/0x868)
 [<c05b9cac>] (_regmap_raw_write_impl) from [<c05b984c>] (_regmap_update_bits+0xe4/0xec)
 [<c05b984c>] (_regmap_update_bits) from [<c05bad04>] (regmap_update_bits_base+0x50/0x74)
 [<c05bad04>] (regmap_update_bits_base) from [<c04d453c>] (regulator_disable_regmap+0x44/0x54)
 [<c04d453c>] (regulator_disable_regmap) from [<c04cf9d4>] (_regulator_do_disable+0xf8/0x268)
 [<c04cf9d4>] (_regulator_do_disable) from [<c04d1694>] (_regulator_disable+0xf4/0x19c)
 [<c04d1694>] (_regulator_disable) from [<c04d1770>] (regulator_disable+0x34/0x64)
 [<c04d1770>] (regulator_disable) from [<c04d2310>] (regulator_bulk_disable+0x28/0xb4)
 [<c04d2310>] (regulator_bulk_disable) from [<c0495cd4>] (tegra_pcie_power_off+0x64/0xa8)
 [<c0495cd4>] (tegra_pcie_power_off) from [<c0495f74>] (tegra_pcie_pm_suspend+0x25c/0x3f4)
 [<c0495f74>] (tegra_pcie_pm_suspend) from [<c05af48c>] (dpm_run_callback+0x38/0x1d4)
 [<c05af48c>] (dpm_run_callback) from [<c05afe30>] (__device_suspend_noirq+0xc0/0x2b8)
 [<c05afe30>] (__device_suspend_noirq) from [<c05b1c24>] (dpm_noirq_suspend_devices+0x100/0x37c)
 [<c05b1c24>] (dpm_noirq_suspend_devices) from [<c05b1ebc>] (dpm_suspend_noirq+0x1c/0x48)
 [<c05b1ebc>] (dpm_suspend_noirq) from [<c017d2c0>] (suspend_devices_and_enter+0x1d0/0xa00)
 [<c017d2c0>] (suspend_devices_and_enter) from [<c017dd10>] (pm_suspend+0x220/0x74c)
 [<c017dd10>] (pm_suspend) from [<c017c2c8>] (state_store+0x6c/0xc8)
 [<c017c2c8>] (state_store) from [<c02ef398>] (kernfs_fop_write+0xe8/0x1c4)
 [<c02ef398>] (kernfs_fop_write) from [<c0271e38>] (__vfs_write+0x2c/0x1c4)
 [<c0271e38>] (__vfs_write) from [<c02748dc>] (vfs_write+0xa4/0x184)
 [<c02748dc>] (vfs_write) from [<c0274b7c>] (ksys_write+0x9c/0xdc)
 [<c0274b7c>] (ksys_write) from [<c0101000>] (ret_fast_syscall+0x0/0x54)
 Exception stack(0xe9f21fa8 to 0xe9f21ff0)
 1fa0:                   0000006c 004b2438 00000004 004b2438 00000004 00000000
 1fc0: 0000006c 004b2438 004b1228 00000004 00000004 00000004 0049e78c 004b1228
 1fe0: 00000004 be9809b8 b6f0bc0b b6e96206

The problem is that the Tegra PCIe driver indirectly uses I2C for
controlling some regulators and the I2C driver is now being suspended
before the PCIe driver causing the PCIe suspend to fail. The Tegra PCIe
driver is suspended during the NOIRQ phase and this cannot be changed
due to other dependencies. Therefore, we also need to move the suspend
handling for the Tegra I2C driver to the NOIRQ phase as well.

In order to move the I2C suspend handling to the NOIRQ phase we also
need to avoid calling pm_runtime_get/put() because per commit
1e2ef05bb8 ("PM: Limit race conditions between runtime PM and system
sleep (v2)") these cannot be called early in resume. The function
tegra_i2c_init(), called during resume, calls pm_runtime_get/put() and
so move these calls outside of tegra_i2c_init(), so this function can
be used during the NOIRQ resume phase.

Fixes: acc8abcb2a ("i2c: tegra: Add suspend-resume support")

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-09-13 15:17:23 +01:00
arch SPDX fixes for 5.3-rc2 2019-07-28 10:00:06 -07:00
block for-linus-20190726-2 2019-07-26 19:20:34 -07:00
certs Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs" 2019-07-10 18:43:43 -07:00
crypto USB / PHY patches for 5.3-rc1 2019-07-11 15:40:06 -07:00
Documentation dt-bindings: i2c: bcm2835: Add brcm,bcm2711 compatible 2019-08-29 20:51:46 +02:00
drivers i2c: tegra: Move suspend handling to NOIRQ phase 2019-09-13 15:17:23 +01:00
fs SPDX fixes for 5.3-rc2 2019-07-28 10:00:06 -07:00
include i2c: replace i2c_new_secondary_device with an ERR_PTR variant 2019-08-14 14:54:55 +02:00
init Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
ipc Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
kernel Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-27 21:22:33 -07:00
lib test_firmware: fix a memory leak bug 2019-07-25 14:39:52 +02:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy() 2019-07-22 10:18:30 +02:00
net tcp: be more careful in tcp_fragment() 2019-07-21 20:41:24 -07:00
samples treewide: remove SPDX "WITH Linux-syscall-note" from kernel-space headers again 2019-07-25 11:05:10 +02:00
scripts Kbuild fixes for v5.3 2019-07-28 10:35:04 -07:00
security meminit fix 2019-07-28 12:33:15 -07:00
sound sound fixes for 5.3-rc2 2019-07-26 10:23:45 -07:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-27 21:17:56 -07:00
usr kbuild: enable arch/s390/include/uapi/asm/zcrypt.h for uapi header test 2019-07-23 10:45:46 +02:00
virt Documentation: move Documentation/virtual to Documentation/virt 2019-07-24 10:52:11 +02:00
.clang-format Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-04-17 11:26:25 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore .gitignore: Add compilation database file 2019-07-27 12:18:19 +09:00
.mailmap MAINTAINERS: Update my email address 2019-07-22 14:57:50 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Remove references to dead website. 2019-07-19 12:22:04 -07:00
Kbuild Kbuild updates for v5.1 2019-03-10 17:48:21 -07:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS i2c: Add i2c-icy for I2C on m68k/Amiga 2019-08-29 21:04:11 +02:00
Makefile Linux 5.3-rc2 2019-07-28 12:47:02 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.