| Message ID | 20220923142437.271328-1-jpanis@baylibre.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | ECAP support on TI AM62x SoC | expand |
On Fri, Sep 23, 2022 at 04:24:33PM +0200, Julien Panis wrote: > The Enhanced Capture (ECAP) module can be used to timestamp events > detected on signal input pin. It can be used for time measurements > of pulse train signals. > > ECAP module includes 4 timestamp capture registers. For all 4 sequenced > timestamp capture events (0->1->2->3->0->...), edge polarity (falling/rising > edge) can be selected. > > This driver leverages counter subsystem to : > - select edge polarity for all 4 capture events (event mode) > - log timestamps for each capture event > Event polarity, and CAP0/1/2/3 timestamps give all the information > about the input pulse train. Further information can easily be computed : > period and/or duty cycle if frequency is constant, elapsed time between > pulses, etc... > > This patchset must be applied on top of the following counter subsystem patchset : > https://lore.kernel.org/all/cover.1663693757.git.william.gray@linaro.org/ Hello Julien, Tentatively, this version looks good to me. Due to the amount of changes we've made in the past week I'm going to let it sit on the list for a while to give any lingering issues we missed a chance to be found. If nothing pops up during that time, I expect to queue this next week and hopefully include it with the other Counter changes in time for the 6.1 merge window. By the way, in the future you can use the '--base' git format-patch argument to specify the base commit (and any prereq patches) that your series is based on: https://git-scm.com/docs/git-format-patch#_base_tree_information That makes it clear to reviewers and maintainers where they should apply your patchset, and should also prevent the kernel test robot from testing against the wrong base. William Breathitt Gray
On Fri, Sep 23, 2022 at 04:24:33PM +0200, Julien Panis wrote: > The Enhanced Capture (ECAP) module can be used to timestamp events > detected on signal input pin. It can be used for time measurements > of pulse train signals. > > ECAP module includes 4 timestamp capture registers. For all 4 sequenced > timestamp capture events (0->1->2->3->0->...), edge polarity (falling/rising > edge) can be selected. > > This driver leverages counter subsystem to : > - select edge polarity for all 4 capture events (event mode) > - log timestamps for each capture event > Event polarity, and CAP0/1/2/3 timestamps give all the information > about the input pulse train. Further information can easily be computed : > period and/or duty cycle if frequency is constant, elapsed time between > pulses, etc... > > This patchset must be applied on top of the following counter subsystem patchset : > https://lore.kernel.org/all/cover.1663693757.git.william.gray@linaro.org/ > > Modifications since v8 : > - Add documentation to private driver structure > - Add mutex to prevent IO race conditions > - Stop counter before disabling interrupts in ecap_cnt_capture_disable() function > - Remove returning of status in ecap_cnt_count_get/set_val() functions > - Remove unnecessary 'return -EBUSY' in all callbacks > - Remove unnecessary '.id = 0' in ecap_cnt_counts[] > - Modify driver info in MAINTAINER file > > Userspace commands : > ### CLOCK SIGNAL ### > cd /sys/bus/counter/devices/counter0/signal0 > > # Get frequency > cat frequency > > ### INPUT SIGNAL ### > cd /sys/bus/counter/devices/counter0/signal1 > > # Get polarity for each capture event > cat polarity0 > cat polarity1 > cat polarity2 > cat polarity3 > > # Set polarity for each capture event > echo positive > polarity0 > echo negative > polarity1 > echo positive > polarity2 > echo negative > polarity3 > > ### COUNT ### > cd /sys/bus/counter/devices/counter0/count0 > > # Get ceiling (counter max value) > cat ceiling > > # Reset number of overflows & current timebase counter value > echo 0 > num_overflows > echo 0 > count > > # Run ECAP > echo 1 > enable > > # Get number of overflows & current timebase counter value > cat num_overflows > cat count > > # Get captured timestamps > cat capture0 > cat capture1 > cat capture2 > cat capture3 > > # Note that counter watches can also be used to get > # data from userspace application > # -> see tools/counter/counter_example.c > > # Pause ECAP > echo 0 > enable > > Julien Panis (4): > dt-bindings: counter: add ti,am62-ecap-capture.yaml > Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows > items > counter: ti-ecap-capture: capture driver support for ECAP > MAINTAINERS: add TI ECAP driver info > > Documentation/ABI/testing/sysfs-bus-counter | 14 + > .../counter/ti,am62-ecap-capture.yaml | 61 ++ > MAINTAINERS | 9 + > drivers/counter/Kconfig | 15 + > drivers/counter/Makefile | 1 + > drivers/counter/ti-ecap-capture.c | 614 ++++++++++++++++++ > 6 files changed, 714 insertions(+) > create mode 100644 Documentation/devicetree/bindings/counter/ti,am62-ecap-capture.yaml > create mode 100644 drivers/counter/ti-ecap-capture.c > > -- > 2.37.3 Queued for counter-next with a minor context adjustment for sysfs-bus-counter changes. Thanks, William Breathitt Gray
The Enhanced Capture (ECAP) module can be used to timestamp events detected on signal input pin. It can be used for time measurements of pulse train signals. ECAP module includes 4 timestamp capture registers. For all 4 sequenced timestamp capture events (0->1->2->3->0->...), edge polarity (falling/rising edge) can be selected. This driver leverages counter subsystem to : - select edge polarity for all 4 capture events (event mode) - log timestamps for each capture event Event polarity, and CAP0/1/2/3 timestamps give all the information about the input pulse train. Further information can easily be computed : period and/or duty cycle if frequency is constant, elapsed time between pulses, etc... This patchset must be applied on top of the following counter subsystem patchset : https://lore.kernel.org/all/cover.1663693757.git.william.gray@linaro.org/ Modifications since v8 : - Add documentation to private driver structure - Add mutex to prevent IO race conditions - Stop counter before disabling interrupts in ecap_cnt_capture_disable() function - Remove returning of status in ecap_cnt_count_get/set_val() functions - Remove unnecessary 'return -EBUSY' in all callbacks - Remove unnecessary '.id = 0' in ecap_cnt_counts[] - Modify driver info in MAINTAINER file Userspace commands : ### CLOCK SIGNAL ### cd /sys/bus/counter/devices/counter0/signal0 # Get frequency cat frequency ### INPUT SIGNAL ### cd /sys/bus/counter/devices/counter0/signal1 # Get polarity for each capture event cat polarity0 cat polarity1 cat polarity2 cat polarity3 # Set polarity for each capture event echo positive > polarity0 echo negative > polarity1 echo positive > polarity2 echo negative > polarity3 ### COUNT ### cd /sys/bus/counter/devices/counter0/count0 # Get ceiling (counter max value) cat ceiling # Reset number of overflows & current timebase counter value echo 0 > num_overflows echo 0 > count # Run ECAP echo 1 > enable # Get number of overflows & current timebase counter value cat num_overflows cat count # Get captured timestamps cat capture0 cat capture1 cat capture2 cat capture3 # Note that counter watches can also be used to get # data from userspace application # -> see tools/counter/counter_example.c # Pause ECAP echo 0 > enable Julien Panis (4): dt-bindings: counter: add ti,am62-ecap-capture.yaml Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows items counter: ti-ecap-capture: capture driver support for ECAP MAINTAINERS: add TI ECAP driver info Documentation/ABI/testing/sysfs-bus-counter | 14 + .../counter/ti,am62-ecap-capture.yaml | 61 ++ MAINTAINERS | 9 + drivers/counter/Kconfig | 15 + drivers/counter/Makefile | 1 + drivers/counter/ti-ecap-capture.c | 614 ++++++++++++++++++ 6 files changed, 714 insertions(+) create mode 100644 Documentation/devicetree/bindings/counter/ti,am62-ecap-capture.yaml create mode 100644 drivers/counter/ti-ecap-capture.c