From: Suman Anna s-anna@ti.com
commit c20c8f750d9f8f8617f07ee2352d3ff560e66bc2 upstream.
The omap_hwmod _enable() function can return success without setting the hwmod state to _HWMOD_STATE_ENABLED for IPs with reset lines when all of the reset lines are asserted. The omap_hwmod _idle() function also performs a similar check, but after checking for the hwmod state first. This triggers the WARN when pm_runtime_get and pm_runtime_put are invoked on IPs with all reset lines asserted. Reverse the checks for hwmod state and reset lines status to fix this.
Issue found during a unbind operation on a device with reset lines still asserted, example backtrace below
------------[ cut here ]------------ WARNING: CPU: 1 PID: 879 at arch/arm/mach-omap2/omap_hwmod.c:2207 _idle+0x1e4/0x240() omap_hwmod: mmu_dsp: idle state can only be entered from enabled state Modules linked in: CPU: 1 PID: 879 Comm: sh Not tainted 4.4.0-00008-ga989d951331a #3 Hardware name: Generic OMAP5 (Flattened Device Tree) [<c0018e60>] (unwind_backtrace) from [<c0014dc4>] (show_stack+0x10/0x14) [<c0014dc4>] (show_stack) from [<c037ac28>] (dump_stack+0x90/0xc0) [<c037ac28>] (dump_stack) from [<c003f420>] (warn_slowpath_common+0x78/0xb4) [<c003f420>] (warn_slowpath_common) from [<c003f48c>] (warn_slowpath_fmt+0x30/0x40) [<c003f48c>] (warn_slowpath_fmt) from [<c0028c20>] (_idle+0x1e4/0x240) [<c0028c20>] (_idle) from [<c0029080>] (omap_hwmod_idle+0x28/0x48) [<c0029080>] (omap_hwmod_idle) from [<c002a5a4>] (omap_device_idle+0x3c/0x90) [<c002a5a4>] (omap_device_idle) from [<c0427a90>] (__rpm_callback+0x2c/0x60) [<c0427a90>] (__rpm_callback) from [<c0427ae4>] (rpm_callback+0x20/0x80) [<c0427ae4>] (rpm_callback) from [<c0427f84>] (rpm_suspend+0x138/0x74c) [<c0427f84>] (rpm_suspend) from [<c0428b78>] (__pm_runtime_idle+0x78/0xa8) [<c0428b78>] (__pm_runtime_idle) from [<c041f514>] (__device_release_driver+0x64/0x100) [<c041f514>] (__device_release_driver) from [<c041f5d0>] (device_release_driver+0x20/0x2c) [<c041f5d0>] (device_release_driver) from [<c041d85c>] (unbind_store+0x78/0xf8) [<c041d85c>] (unbind_store) from [<c0206df8>] (kernfs_fop_write+0xc0/0x1c4) [<c0206df8>] (kernfs_fop_write) from [<c018a120>] (__vfs_write+0x20/0xdc) [<c018a120>] (__vfs_write) from [<c018a9cc>] (vfs_write+0x90/0x164) [<c018a9cc>] (vfs_write) from [<c018b1f0>] (SyS_write+0x44/0x9c) [<c018b1f0>] (SyS_write) from [<c0010420>] (ret_fast_syscall+0x0/0x1c) ---[ end trace a4182013c75a9f50 ]---
While at this, fix the sequence in _shutdown() as well, though there is no easy reproducible scenario.
Fixes: 747834ab8347 ("ARM: OMAP2+: hwmod: revise hardreset behavior") Signed-off-by: Suman Anna s-anna@ti.com Signed-off-by: Paul Walmsley paul@pwsan.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm/mach-omap2/omap_hwmod.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
--- a/arch/arm/mach-omap2/omap_hwmod.c +++ b/arch/arm/mach-omap2/omap_hwmod.c @@ -2207,15 +2207,15 @@ static int _idle(struct omap_hwmod *oh)
pr_debug("omap_hwmod: %s: idling\n", oh->name);
+ if (_are_all_hardreset_lines_asserted(oh)) + return 0; + if (oh->_state != _HWMOD_STATE_ENABLED) { WARN(1, "omap_hwmod: %s: idle state can only be entered from enabled state\n", oh->name); return -EINVAL; }
- if (_are_all_hardreset_lines_asserted(oh)) - return 0; - if (oh->class->sysc) _idle_sysc(oh); _del_initiator_dep(oh, mpu_oh); @@ -2262,6 +2262,9 @@ static int _shutdown(struct omap_hwmod * int ret, i; u8 prev_state;
+ if (_are_all_hardreset_lines_asserted(oh)) + return 0; + if (oh->_state != _HWMOD_STATE_IDLE && oh->_state != _HWMOD_STATE_ENABLED) { WARN(1, "omap_hwmod: %s: disabled state can only be entered from idle, or enabled state\n", @@ -2269,9 +2272,6 @@ static int _shutdown(struct omap_hwmod * return -EINVAL; }
- if (_are_all_hardreset_lines_asserted(oh)) - return 0; - pr_debug("omap_hwmod: %s: disabling\n", oh->name);
if (oh->class->pre_shutdown) {