From c2c2cc859290886e36ebed70c7ce4d5056f980fe Mon Sep 17 00:00:00 2001
From: Marian Buschsieweke <marian.buschsieweke@ml-pa.com>
Date: Tue, 22 Oct 2024 21:40:30 +0200
Subject: [PATCH] drivers/periph_gpio: let gpio_read() return bool

Since https://github.com/RIOT-OS/RIOT/pull/20935 gpio_write()
uses a `bool` instead of an `int`. This does the same treatment for
`gpio_read()`.

This does indeed add an instruction to `gpio_read()` implementations.
However, users caring about an instruction more are better served with
`gpio_ll_read()` anyway. And `gpio_read() == 1` is often seen in
newcomer's code, which would now work as expected.
---
 cpu/atmega_common/periph/gpio.c | 2 +-
 cpu/atxmega/periph/gpio.c       | 2 +-
 cpu/cc2538/periph/gpio.c        | 2 +-
 cpu/cc26xx_cc13xx/periph/gpio.c | 2 +-
 cpu/efm32/periph/gpio.c         | 2 +-
 cpu/esp32/periph/gpio.c         | 4 ++--
 cpu/esp8266/periph/gpio.c       | 2 +-
 cpu/fe310/periph/gpio.c         | 2 +-
 cpu/gd32v/periph/gpio.c         | 2 +-
 cpu/kinetis/periph/gpio.c       | 2 +-
 cpu/lm4f120/periph/gpio.c       | 2 +-
 cpu/lpc1768/periph/gpio.c       | 2 +-
 cpu/lpc23xx/periph/gpio.c       | 2 +-
 cpu/msp430/periph/gpio.c        | 2 +-
 cpu/native/periph/gpio_linux.c  | 2 +-
 cpu/native/periph/gpio_mock.c   | 2 +-
 cpu/nrf5x_common/periph/gpio.c  | 2 +-
 cpu/qn908x/periph/gpio.c        | 2 +-
 cpu/rpx0xx/periph/gpio.c        | 2 +-
 cpu/sam0_common/periph/gpio.c   | 2 +-
 cpu/sam3/periph/gpio.c          | 2 +-
 cpu/stm32/periph/gpio_all.c     | 2 +-
 cpu/stm32/periph/gpio_f1.c      | 2 +-
 drivers/include/periph/gpio.h   | 6 +++---
 24 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/cpu/atmega_common/periph/gpio.c b/cpu/atmega_common/periph/gpio.c
index b59a1f703e..28e050d69f 100644
--- a/cpu/atmega_common/periph/gpio.c
+++ b/cpu/atmega_common/periph/gpio.c
@@ -154,7 +154,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     return (_SFR_MEM8(atmega_pin_addr(pin)) & (1 << atmega_pin_num(pin)));
 }
diff --git a/cpu/atxmega/periph/gpio.c b/cpu/atxmega/periph/gpio.c
index 8f67990e05..dd6914ec07 100644
--- a/cpu/atxmega/periph/gpio.c
+++ b/cpu/atxmega/periph/gpio.c
@@ -252,7 +252,7 @@ void gpio_irq_disable(gpio_t pin)
     }
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     PORT_t *port = _port_addr(pin);
     uint8_t pin_mask = _pin_mask(pin);
diff --git a/cpu/cc2538/periph/gpio.c b/cpu/cc2538/periph/gpio.c
index 861810d4f9..82bf84e416 100644
--- a/cpu/cc2538/periph/gpio.c
+++ b/cpu/cc2538/periph/gpio.c
@@ -122,7 +122,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     return (int)(gpio(pin)->DATA & _pin_mask(pin));
 }
diff --git a/cpu/cc26xx_cc13xx/periph/gpio.c b/cpu/cc26xx_cc13xx/periph/gpio.c
index 82847bb194..17ad877d20 100644
--- a/cpu/cc26xx_cc13xx/periph/gpio.c
+++ b/cpu/cc26xx_cc13xx/periph/gpio.c
@@ -56,7 +56,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     if (GPIO->DOE & (1 << pin)) {
         return (GPIO->DOUT >> pin) & 1;
diff --git a/cpu/efm32/periph/gpio.c b/cpu/efm32/periph/gpio.c
index 589c7adf3e..0d37f1c8ae 100644
--- a/cpu/efm32/periph/gpio.c
+++ b/cpu/efm32/periph/gpio.c
@@ -73,7 +73,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     return GPIO_PinInGet(_port_num(pin), _pin_num(pin));
 }
diff --git a/cpu/esp32/periph/gpio.c b/cpu/esp32/periph/gpio.c
index 9050f011f1..137a7402a1 100644
--- a/cpu/esp32/periph/gpio.c
+++ b/cpu/esp32/periph/gpio.c
@@ -338,7 +338,7 @@ static gpio_hal_context_t _gpio_hal_ctx = {
  */
 static BITFIELD(_output, GPIO_PIN_NUMOF);
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     assert(pin < GPIO_PIN_NUMOF);
 
@@ -394,7 +394,7 @@ void gpio_toggle(gpio_t pin)
 
 #else /* IS_USED(MODULE_ESP_IDF_GPIO_HAL) */
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     assert(pin < GPIO_PIN_NUMOF);
 
diff --git a/cpu/esp8266/periph/gpio.c b/cpu/esp8266/periph/gpio.c
index d94f3ab8d7..414516e693 100644
--- a/cpu/esp8266/periph/gpio.c
+++ b/cpu/esp8266/periph/gpio.c
@@ -237,7 +237,7 @@ void gpio_irq_disable (gpio_t pin)
 }
 #endif /* MODULE_PERIPH_GPIO_IRQ */
 
-int gpio_read (gpio_t pin)
+bool gpio_read (gpio_t pin)
 {
     CHECK_PARAM_RET(pin < GPIO_PIN_NUMOF, -1);
 
diff --git a/cpu/fe310/periph/gpio.c b/cpu/fe310/periph/gpio.c
index c923b8e3e1..c7db92d517 100644
--- a/cpu/fe310/periph/gpio.c
+++ b/cpu/fe310/periph/gpio.c
@@ -90,7 +90,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     return (GPIO_REG(GPIO_INPUT_VAL) & (1 << pin)) ? 1 : 0;
 }
diff --git a/cpu/gd32v/periph/gpio.c b/cpu/gd32v/periph/gpio.c
index f15ed83669..7fbfcbde4d 100644
--- a/cpu/gd32v/periph/gpio.c
+++ b/cpu/gd32v/periph/gpio.c
@@ -160,7 +160,7 @@ void gpio_init_analog(gpio_t pin)
     *pin_reg &= ~(0xfl << (4 * (pin_num - ((pin_num >= 8) * 8))));
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     GPIO_Type *port = _port(pin);
     unsigned pin_num = _pin_num(pin);
diff --git a/cpu/kinetis/periph/gpio.c b/cpu/kinetis/periph/gpio.c
index df62aa6f89..ff918b6250 100644
--- a/cpu/kinetis/periph/gpio.c
+++ b/cpu/kinetis/periph/gpio.c
@@ -247,7 +247,7 @@ void gpio_init_port(gpio_t pin, uint32_t pcr)
 #endif /* KINETIS_HAVE_PCR */
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     if (gpio(pin)->PDDR & (1 << pin_num(pin))) {
         return (gpio(pin)->PDOR & (1 << pin_num(pin))) ? 1 : 0;
diff --git a/cpu/lm4f120/periph/gpio.c b/cpu/lm4f120/periph/gpio.c
index 7d158616a7..a03a97eb0a 100644
--- a/cpu/lm4f120/periph/gpio.c
+++ b/cpu/lm4f120/periph/gpio.c
@@ -119,7 +119,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     const uint8_t port_num = _port_num(pin);
     const uint32_t port_addr = _port_base[port_num];
diff --git a/cpu/lpc1768/periph/gpio.c b/cpu/lpc1768/periph/gpio.c
index 75b3217c50..668673f222 100644
--- a/cpu/lpc1768/periph/gpio.c
+++ b/cpu/lpc1768/periph/gpio.c
@@ -92,7 +92,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     LPC_GPIO_TypeDef *base = _base(pin);
 
diff --git a/cpu/lpc23xx/periph/gpio.c b/cpu/lpc23xx/periph/gpio.c
index 88033646c9..131ecd46ca 100644
--- a/cpu/lpc23xx/periph/gpio.c
+++ b/cpu/lpc23xx/periph/gpio.c
@@ -99,7 +99,7 @@ int gpio_init_mux(unsigned pin, unsigned mux)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     unsigned _pin = pin & 31;
     unsigned port = pin >> 5;
diff --git a/cpu/msp430/periph/gpio.c b/cpu/msp430/periph/gpio.c
index af1ea5ec8c..402493d7c9 100644
--- a/cpu/msp430/periph/gpio.c
+++ b/cpu/msp430/periph/gpio.c
@@ -112,7 +112,7 @@ void gpio_periph_mode(gpio_t pin, bool enable)
     }
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     msp430_port_t *port = _port(pin);
     if (port->DIR & _pin_mask(pin)) {
diff --git a/cpu/native/periph/gpio_linux.c b/cpu/native/periph/gpio_linux.c
index a554628d97..2b32790e99 100644
--- a/cpu/native/periph/gpio_linux.c
+++ b/cpu/native/periph/gpio_linux.c
@@ -167,7 +167,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     struct gpiohandle_data data;
 
diff --git a/cpu/native/periph/gpio_mock.c b/cpu/native/periph/gpio_mock.c
index a335f2ddec..3094be3144 100644
--- a/cpu/native/periph/gpio_mock.c
+++ b/cpu/native/periph/gpio_mock.c
@@ -66,7 +66,7 @@ __attribute__((weak)) void gpio_irq_disable(gpio_t pin)
     (void) pin;
 }
 
-__attribute__((weak)) int gpio_read(gpio_t pin) {
+__attribute__((weak)) bool gpio_read(gpio_t pin) {
   if (pin) {
     return pin->value;
   }
diff --git a/cpu/nrf5x_common/periph/gpio.c b/cpu/nrf5x_common/periph/gpio.c
index 2ede21d588..7f58963f3c 100644
--- a/cpu/nrf5x_common/periph/gpio.c
+++ b/cpu/nrf5x_common/periph/gpio.c
@@ -126,7 +126,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     if (port(pin)->DIR & (1 << pin_num(pin))) {
         return (port(pin)->OUT & (1 << pin_num(pin))) ? 1 : 0;
diff --git a/cpu/qn908x/periph/gpio.c b/cpu/qn908x/periph/gpio.c
index 761eefbf37..6258f325ce 100644
--- a/cpu/qn908x/periph/gpio.c
+++ b/cpu/qn908x/periph/gpio.c
@@ -182,7 +182,7 @@ void gpio_irq_disable(gpio_t pin)
 
 #endif /* defined(MODULE_PERIPH_GPIO_IRQ) */
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     return ((GPIO_T_ADDR(pin)->DATA) >> GPIO_T_PIN(pin)) & 1u;
 }
diff --git a/cpu/rpx0xx/periph/gpio.c b/cpu/rpx0xx/periph/gpio.c
index f8ec327404..859947e120 100644
--- a/cpu/rpx0xx/periph/gpio.c
+++ b/cpu/rpx0xx/periph/gpio.c
@@ -106,7 +106,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     if (SIO->GPIO_OE & (1LU << pin)) {
         /* pin is output: */
diff --git a/cpu/sam0_common/periph/gpio.c b/cpu/sam0_common/periph/gpio.c
index 5fd7ed2057..50129c130d 100644
--- a/cpu/sam0_common/periph/gpio.c
+++ b/cpu/sam0_common/periph/gpio.c
@@ -195,7 +195,7 @@ int gpio_init(gpio_t pin, gpio_mode_t mode)
     return 0;
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     PortGroup *port;
     int mask = _pin_mask(pin);
diff --git a/cpu/sam3/periph/gpio.c b/cpu/sam3/periph/gpio.c
index 4edee67e3d..6253814094 100644
--- a/cpu/sam3/periph/gpio.c
+++ b/cpu/sam3/periph/gpio.c
@@ -244,7 +244,7 @@ void gpio_irq_disable(gpio_t pin)
     NVIC_DisableIRQ((1 << (_port_num(pin) + PIOA_IRQn)));
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     Pio *port = _port(pin);
     int pin_num = _pin_num(pin);
diff --git a/cpu/stm32/periph/gpio_all.c b/cpu/stm32/periph/gpio_all.c
index f7403b463f..526deccbb6 100644
--- a/cpu/stm32/periph/gpio_all.c
+++ b/cpu/stm32/periph/gpio_all.c
@@ -203,7 +203,7 @@ void gpio_irq_disable(gpio_t pin)
     EXTI_REG_IMR &= ~(1 << _pin_num(pin));
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     return (_port(pin)->IDR & (1 << _pin_num(pin)));
 }
diff --git a/cpu/stm32/periph/gpio_f1.c b/cpu/stm32/periph/gpio_f1.c
index 18359fa137..0896765057 100644
--- a/cpu/stm32/periph/gpio_f1.c
+++ b/cpu/stm32/periph/gpio_f1.c
@@ -145,7 +145,7 @@ void gpio_init_analog(gpio_t pin)
     *(uint32_t *)(&_port(pin)->CRL + (pin_num >= 8)) &= ~(0xfl << (4 * (pin_num - ((pin_num >= 8) * 8))));
 }
 
-int gpio_read(gpio_t pin)
+bool gpio_read(gpio_t pin)
 {
     GPIO_TypeDef *port = _port(pin);
     int pin_num = _pin_num(pin);
diff --git a/drivers/include/periph/gpio.h b/drivers/include/periph/gpio.h
index 8a07104984..57861880d4 100644
--- a/drivers/include/periph/gpio.h
+++ b/drivers/include/periph/gpio.h
@@ -227,10 +227,10 @@ void gpio_irq_disable(gpio_t pin);
  *
  * @param[in] pin       the pin to read
  *
- * @return              0 when pin is LOW
- * @return              >0 for HIGH
+ * @retval              false   pin is LOW
+ * @retval              true    pin is HIGH
  */
-int gpio_read(gpio_t pin);
+bool gpio_read(gpio_t pin);
 
 /**
  * @brief   Set the given pin to HIGH