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-f4...@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
