diff options
author | Philippe Mathieu-Daudé <f4bug@amsat.org> | 2020-06-23 09:27:20 +0200 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2020-06-26 14:30:28 +0100 |
commit | b989b89f672597cc0e780b5ce95e604d4f49247a (patch) | |
tree | e332f21c0dfa097b3a5202cfe8e09941479e37dc /hw/misc/pca9552.c | |
parent | 2df252d8793097386d4972640653da93f7857da1 (diff) |
hw/misc/pca9552: Trace GPIO High/Low events
Add a trivial representation of the PCA9552 GPIOs.
Example booting obmc-phosphor-image:
$ qemu-system-arm -M witherspoon-bmc -trace pca955x_gpio_status
1592689902.327837:pca955x_gpio_status pca-unspecified GPIOs 0-15 [*...............]
1592689902.329934:pca955x_gpio_status pca-unspecified GPIOs 0-15 [**..............]
1592689902.330717:pca955x_gpio_status pca-unspecified GPIOs 0-15 [***.............]
1592689902.331431:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****............]
1592689902.332163:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*..]
1592689902.332888:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........**.]
1592689902.333629:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........***]
1592690032.793289:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*]
1592690033.303163:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........***]
1592690033.812962:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*]
1592690034.323234:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........***]
1592690034.832922:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*]
We notice the GPIO #14 (front-power LED) starts to blink.
This LED is described in the witherspoon device-tree [*]:
front-power {
retain-state-shutdown;
default-state = "keep";
gpios = <&pca0 14 GPIO_ACTIVE_LOW>;
};
[*] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts?id=b1f9be9392f0#n140
Suggested-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20200623072723.6324-7-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw/misc/pca9552.c')
-rw-r--r-- | hw/misc/pca9552.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c index 2cc52b0205..41f8ad213d 100644 --- a/hw/misc/pca9552.c +++ b/hw/misc/pca9552.c @@ -13,12 +13,14 @@ #include "qemu/osdep.h" #include "qemu/log.h" #include "qemu/module.h" +#include "qemu/bitops.h" #include "hw/qdev-properties.h" #include "hw/misc/pca9552.h" #include "hw/misc/pca9552_regs.h" #include "migration/vmstate.h" #include "qapi/error.h" #include "qapi/visitor.h" +#include "trace.h" typedef struct PCA955xClass { /*< private >*/ @@ -49,6 +51,39 @@ static uint8_t pca955x_pin_get_config(PCA955xState *s, int pin) return extract32(s->regs[reg], shift, 2); } +/* Return INPUT status (bit #N belongs to GPIO #N) */ +static uint16_t pca955x_pins_get_status(PCA955xState *s) +{ + return (s->regs[PCA9552_INPUT1] << 8) | s->regs[PCA9552_INPUT0]; +} + +static void pca955x_display_pins_status(PCA955xState *s, + uint16_t previous_pins_status) +{ + PCA955xClass *k = PCA955X_GET_CLASS(s); + uint16_t pins_status, pins_changed; + int i; + + pins_status = pca955x_pins_get_status(s); + pins_changed = previous_pins_status ^ pins_status; + if (!pins_changed) { + return; + } + if (trace_event_get_state_backends(TRACE_PCA955X_GPIO_STATUS)) { + char *buf = g_newa(char, k->pin_count + 1); + + for (i = 0; i < k->pin_count; i++) { + if (extract32(pins_status, i, 1)) { + buf[i] = '*'; + } else { + buf[i] = '.'; + } + } + buf[i] = '\0'; + trace_pca955x_gpio_status(s->description, buf); + } +} + static void pca955x_update_pin_input(PCA955xState *s) { PCA955xClass *k = PCA955X_GET_CLASS(s); @@ -98,6 +133,8 @@ static uint8_t pca955x_read(PCA955xState *s, uint8_t reg) static void pca955x_write(PCA955xState *s, uint8_t reg, uint8_t data) { + uint16_t pins_status; + switch (reg) { case PCA9552_PSC0: case PCA9552_PWM0: @@ -110,8 +147,10 @@ static void pca955x_write(PCA955xState *s, uint8_t reg, uint8_t data) case PCA9552_LS1: case PCA9552_LS2: case PCA9552_LS3: + pins_status = pca955x_pins_get_status(s); s->regs[reg] = data; pca955x_update_pin_input(s); + pca955x_display_pins_status(s, pins_status); break; case PCA9552_INPUT0: |