diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c index f00a149d61..2ae13af35e 100644 --- a/hw/misc/pca9552.c +++ b/hw/misc/pca9552.c @@ -44,6 +44,8 @@ DECLARE_CLASS_CHECKERS(PCA955xClass, PCA955X, #define PCA9552_LED_OFF 0x1 #define PCA9552_LED_PWM0 0x2 #define PCA9552_LED_PWM1 0x3 +#define PCA9552_PIN_LOW 0x0 +#define PCA9552_PIN_HIZ 0x1 static const char *led_state[] = {"on", "off", "pwm0", "pwm1"}; @@ -110,22 +112,27 @@ static void pca955x_update_pin_input(PCA955xState *s) for (i = 0; i < k->pin_count; i++) { uint8_t input_reg = PCA9552_INPUT0 + (i / 8); - uint8_t input_shift = (i % 8); + uint8_t bit_mask = 1 << (i % 8); uint8_t config = pca955x_pin_get_config(s, i); + uint8_t old_value = s->regs[input_reg] & bit_mask; + uint8_t new_value; switch (config) { case PCA9552_LED_ON: /* Pin is set to 0V to turn on LED */ - qemu_set_irq(s->gpio[i], 0); - s->regs[input_reg] &= ~(1 << input_shift); + s->regs[input_reg] &= ~bit_mask; break; case PCA9552_LED_OFF: /* * Pin is set to Hi-Z to turn off LED and - * pullup sets it to a logical 1. + * pullup sets it to a logical 1 unless + * external device drives it low. */ - qemu_set_irq(s->gpio[i], 1); - s->regs[input_reg] |= 1 << input_shift; + if (s->ext_state[i] == PCA9552_PIN_LOW) { + s->regs[input_reg] &= ~bit_mask; + } else { + s->regs[input_reg] |= bit_mask; + } break; case PCA9552_LED_PWM0: case PCA9552_LED_PWM1: @@ -133,6 +140,12 @@ static void pca955x_update_pin_input(PCA955xState *s) default: break; } + + /* update irq state only if pin state changed */ + new_value = s->regs[input_reg] & bit_mask; + if (new_value != old_value) { + qemu_set_irq(s->gpio_out[i], !!new_value); + } } } @@ -340,6 +353,7 @@ static const VMStateDescription pca9552_vmstate = { VMSTATE_UINT8(len, PCA955xState), VMSTATE_UINT8(pointer, PCA955xState), VMSTATE_UINT8_ARRAY(regs, PCA955xState, PCA955X_NR_REGS), + VMSTATE_UINT8_ARRAY(ext_state, PCA955xState, PCA955X_PIN_COUNT_MAX), VMSTATE_I2C_SLAVE(i2c, PCA955xState), VMSTATE_END_OF_LIST() } @@ -358,6 +372,7 @@ static void pca9552_reset(DeviceState *dev) s->regs[PCA9552_LS2] = 0x55; s->regs[PCA9552_LS3] = 0x55; + memset(s->ext_state, PCA9552_PIN_HIZ, PCA955X_PIN_COUNT_MAX); pca955x_update_pin_input(s); s->pointer = 0xFF; @@ -380,6 +395,26 @@ static void pca955x_initfn(Object *obj) } } +static void pca955x_set_ext_state(PCA955xState *s, int pin, int level) +{ + if (s->ext_state[pin] != level) { + uint16_t pins_status = pca955x_pins_get_status(s); + s->ext_state[pin] = level; + pca955x_update_pin_input(s); + pca955x_display_pins_status(s, pins_status); + } +} + +static void pca955x_gpio_in_handler(void *opaque, int pin, int level) +{ + + PCA955xState *s = PCA955X(opaque); + PCA955xClass *k = PCA955X_GET_CLASS(s); + + assert((pin >= 0) && (pin < k->pin_count)); + pca955x_set_ext_state(s, pin, level); +} + static void pca955x_realize(DeviceState *dev, Error **errp) { PCA955xClass *k = PCA955X_GET_CLASS(dev); @@ -389,7 +424,8 @@ static void pca955x_realize(DeviceState *dev, Error **errp) s->description = g_strdup("pca-unspecified"); } - qdev_init_gpio_out(dev, s->gpio, k->pin_count); + qdev_init_gpio_out(dev, s->gpio_out, k->pin_count); + qdev_init_gpio_in(dev, pca955x_gpio_in_handler, k->pin_count); } static Property pca955x_properties[] = { diff --git a/include/hw/misc/pca9552.h b/include/hw/misc/pca9552.h index b6f4e264fe..c36525f0c3 100644 --- a/include/hw/misc/pca9552.h +++ b/include/hw/misc/pca9552.h @@ -30,7 +30,8 @@ struct PCA955xState { uint8_t pointer; uint8_t regs[PCA955X_NR_REGS]; - qemu_irq gpio[PCA955X_PIN_COUNT_MAX]; + qemu_irq gpio_out[PCA955X_PIN_COUNT_MAX]; + uint8_t ext_state[PCA955X_PIN_COUNT_MAX]; char *description; /* For debugging purpose only */ };