[PATCH v3 0/4] hw/misc/pca9552: Trace LED On/Off events

[Philippe Mathieu-Daudé]

This series add trace events to better display LEDs changes.
This helps me to work on a generic LED device, see:
https://www.mail-archive.com/qemu-devel@nongnu.org/msg711917.html

Example when booting an obmc-phosphor-image, we can see the LED #14
(front-power LED) starting to blink.

- ASCII LED bar view:

  $ qemu-system-arm -M witherspoon-bmc -trace pca9552_leds_status
  19286@1592574170.202791:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[*...............]
  19286@1592574170.203609:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[**..............]
  19286@1592574170.204102:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[***.............]
  19286@1592574170.204415:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****............]
  19286@1592574170.204758:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........*..]
  19286@1592574170.205070:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........**.]
  19286@1592574170.205380:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........***]
  19286@1592574235.384845:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........*.*]
  19286@1592574235.894049:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........***]
  19286@1592574236.404277:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........*.*]
  19286@1592574236.914644:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........***]
  19286@1592574237.424558:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........*.*]
  19286@1592574237.934580:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........***]
  19286@1592574238.444688:pca9552_leds_status 0x55dde47807c0 LEDs 0-15 
[****.........*.*]

- Only display LEDs which status changes:

  $ qemu-system-arm -M witherspoon-bmc -trace pca9552_led_change
  23367@1592575218.896117:pca9552_led_change 0x557cb6896d80 LED id:0 status: 0 
-> 1
  23367@1592575218.897072:pca9552_led_change 0x557cb6896d80 LED id:1 status: 0 
-> 1
  23367@1592575218.897487:pca9552_led_change 0x557cb6896d80 LED id:2 status: 0 
-> 1
  23367@1592575218.897855:pca9552_led_change 0x557cb6896d80 LED id:3 status: 0 
-> 1
  23367@1592575218.898256:pca9552_led_change 0x557cb6896d80 LED id:13 status: 0 
-> 1
  23367@1592575218.898663:pca9552_led_change 0x557cb6896d80 LED id:14 status: 0 
-> 1
  23367@1592575218.899138:pca9552_led_change 0x557cb6896d80 LED id:15 status: 0 
-> 1
  23367@1592575281.593379:pca9552_led_change 0x557cb6896d80 LED id:14 status: 1 
-> 0
  23367@1592575282.102994:pca9552_led_change 0x557cb6896d80 LED id:14 status: 0 
-> 1
  23367@1592575282.613558:pca9552_led_change 0x557cb6896d80 LED id:14 status: 1 
-> 0
  23367@1592575283.122774:pca9552_led_change 0x557cb6896d80 LED id:14 status: 0 
-> 1

For information about how to test the obmc-phosphor-image, see:
https://www.mail-archive.com/qemu-devel@nongnu.org/msg712911.html

Supersedes: <20200617064734.26956-1-f4bug@amsat.org>

Philippe Mathieu-Daudé (4):
  hw/misc/pca9552: Replace magic value by PCA9552_LED_COUNT definition
  hw/misc/pca9552: Add a PCA955X_LED_MAX definition
  hw/misc/pca9552: Trace LED On/Off events
  hw/misc/pca9552: Trace LED change events

 include/hw/misc/pca9552.h |  2 ++
 hw/misc/pca9552.c         | 60 ++++++++++++++++++++++++++++++++++++++-
 hw/misc/trace-events      |  4 +++
 3 files changed, 65 insertions(+), 1 deletion(-)

-- 
2.21.3