[PATCH v2 00/23] counter: cleanups and device lifetime fixes

Uwe Kleine-König u.kleine-koenig at pengutronix.de
Mon Dec 27 01:45:03 PST 2021


Hello,

this is v2 of this series, it's goal is to fix struct device lifetime issues as
pointed out in patch #13. The patches up to patch #12 are only prepatory and
cleanup patches. Patch #13 provides the needed functions to fix the issues in
all drivers (patches #15 to #22). The last patch removes the then unused API
calls.

The changes compared to v1 is only build fixes that I missed to include in v1,
they were only in my working copy. Additionally I changed:

diff --git a/drivers/counter/counter-core.c b/drivers/counter/counter-core.c
index cdc6004a7e77..3f7dc5718423 100644
--- a/drivers/counter/counter-core.c
+++ b/drivers/counter/counter-core.c
@@ -27,7 +27,7 @@ static DEFINE_IDA(counter_ida);
 
 struct counter_device_allochelper {
 	struct counter_device counter;
-	unsigned long privdata[0];
+	unsigned long privdata[];
 };
 
 static void counter_device_release(struct device *dev)

The stm32-timer-cnt driver was used to test
this series, the other drivers are only compile tested.


To complete the information from the v1 thread: There are a few more
issues I found while working on this patch set:

 - 104_QUAD_8 depends on X86, but compiles fine on ARCH=arm. Maybe
   adding support for COMPILE_TEST would be a good idea.

 - 104-quad-8.c uses devm_request_irq() and (now) devm_counter_add(). On
   unbind an irq might be pending which results in quad8_irq_handler()
   calling counter_push_event() for a counter that is already
   unregistered. (The issue exists also without my changes.)

 - I think intel-qep.c makes the counter unfunctional in
   intel_qep_remove before the counter is unregistered.

 - I wonder why counter is a bus and not a class device type. There is
   no driver that would ever bind a counter device, is there? So
   /sys/bus/counter/driver is always empty.

Do whatever you want with this list, I won't address these in the near
future.

Uwe Kleine-König (23):
  counter: Use container_of instead of drvdata to track counter_device
  counter: ftm-quaddec: Drop unused platform_set_drvdata()
  counter: microchip-tcb-capture: Drop unused platform_set_drvdata()
  counter: Provide a wrapper to access device private data
  counter: 104-quad-8: Convert to counter_priv() wrapper
  counter: interrupt-cnt: Convert to counter_priv() wrapper
  counter: microchip-tcb-capture: Convert to counter_priv() wrapper
  counter: intel-qep: Convert to counter_priv() wrapper
  counter: ftm-quaddec: Convert to counter_priv() wrapper
  counter: ti-eqep: Convert to counter_priv() wrapper
  counter: stm32-lptimer-cnt: Convert to counter_priv() wrapper
  counter: stm32-timer-cnt: Convert to counter_priv() wrapper
  counter: Provide alternative counter registration functions
  counter: Update documentation for new counter registration functions
  counter: 104-quad-8: Convert to new counter registration
  counter: interrupt-cnt: Convert to new counter registration
  counter: intel-qep: Convert to new counter registration
  counter: ftm-quaddec: Convert to new counter registration
  counter: microchip-tcb-capture: Convert to new counter registration
  counter: stm32-timer-cnt: Convert to new counter registration
  counter: stm32-lptimer-cnt: Convert to new counter registration
  counter: ti-eqep: Convert to new counter registration
  counter: remove old and now unused registration API

 Documentation/driver-api/generic-counter.rst |  10 +-
 drivers/counter/104-quad-8.c                 |  93 +++++-----
 drivers/counter/counter-core.c               | 168 +++++++++++++------
 drivers/counter/ftm-quaddec.c                |  37 ++--
 drivers/counter/intel-qep.c                  |  46 ++---
 drivers/counter/interrupt-cnt.c              |  38 +++--
 drivers/counter/microchip-tcb-capture.c      |  44 ++---
 drivers/counter/stm32-lptimer-cnt.c          |  51 +++---
 drivers/counter/stm32-timer-cnt.c            |  48 +++---
 drivers/counter/ti-eqep.c                    |  47 +++---
 include/linux/counter.h                      |  15 +-
 11 files changed, 348 insertions(+), 249 deletions(-)


base-commit: a7904a538933c525096ca2ccde1e60d0ee62c08e
-- 
2.33.0




More information about the linux-arm-kernel mailing list