This series add trace events to better display GPIO changes. We'll continue in the following series by connecting LEDs to these GPIOs.
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_gpio_status 1592689902.327837:pca9552_gpio_status pca-unspecified GPIOs 0-15 [*...............] 1592689902.329934:pca9552_gpio_status pca-unspecified GPIOs 0-15 [**..............] 1592689902.330717:pca9552_gpio_status pca-unspecified GPIOs 0-15 [***.............] 1592689902.331431:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****............] 1592689902.332163:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........*..] 1592689902.332888:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........**.] 1592689902.333629:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........***] 1592690032.793289:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*] 1592690033.303163:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........***] 1592690033.812962:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*] 1592690034.323234:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........***] 1592690034.832922:pca9552_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*] - Only display GPIOs which status changes: $ qemu-system-arm -M witherspoon-bmc -trace pca9552_gpio_change 1592690552.687372:pca9552_gpio_change pca1 GPIO id:0 status: 0 -> 1 1592690552.690169:pca9552_gpio_change pca1 GPIO id:1 status: 0 -> 1 1592690552.691673:pca9552_gpio_change pca1 GPIO id:2 status: 0 -> 1 1592690552.696886:pca9552_gpio_change pca1 GPIO id:3 status: 0 -> 1 1592690552.698614:pca9552_gpio_change pca1 GPIO id:13 status: 0 -> 1 1592690552.699833:pca9552_gpio_change pca1 GPIO id:14 status: 0 -> 1 1592690552.700842:pca9552_gpio_change pca1 GPIO id:15 status: 0 -> 1 1592690683.841921:pca9552_gpio_change pca1 GPIO id:14 status: 1 -> 0 1592690683.861660:pca9552_gpio_change pca1 GPIO id:14 status: 0 -> 1 1592690684.371460:pca9552_gpio_change pca1 GPIO id:14 status: 1 -> 0 1592690684.882115:pca9552_gpio_change pca1 GPIO id:14 status: 0 -> 1 1592690685.391411:pca9552_gpio_change pca1 GPIO id:14 status: 1 -> 0 1592690685.901391:pca9552_gpio_change pca1 GPIO 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: <20200619145101.1637-1-f4...@amsat.org> Based-on: <20200620162818.22340-1-f4...@amsat.org> Philippe Mathieu-Daudé (8): hw/i2c/core: Add i2c_try_create_slave() and i2c_realize_and_unref() hw/misc/pca9552: Replace magic value by PCA9552_PIN_COUNT definition hw/misc/pca9552: Use the PCA9552_PIN_COUNT definition hw/misc/pca9552: Add a 'description' property for debugging purpose hw/misc/pca9552: Trace GPIO High/Low events hw/arm/aspeed: Describe each PCA9552 device hw/misc/pca9552: Trace GPIO change events hw/misc/pca9552: Model qdev output GPIOs include/hw/i2c/i2c.h | 2 ++ include/hw/misc/pca9552.h | 4 +++ hw/arm/aspeed.c | 13 ++++--- hw/i2c/core.c | 18 ++++++++-- hw/misc/pca9552.c | 72 ++++++++++++++++++++++++++++++++++++++- hw/misc/trace-events | 4 +++ 6 files changed, 106 insertions(+), 7 deletions(-) -- 2.21.3