stm32/i2cslave: Add support for H7 MCUs.

ports/stm32/i2cslave.c

@@ -60,7 +60,7 @@ void i2c_slave_ev_irq_handler(i2c_slave_t *i2c) {
     }
 }
 
-#elif defined(STM32F7)
+#elif defined(STM32F7) || defined(STM32H7)
 
 void i2c_slave_init_helper(i2c_slave_t *i2c, int addr) {
     i2c->CR1 = I2C_CR1_STOPIE | I2C_CR1_ADDRIE | I2C_CR1_RXIE | I2C_CR1_TXIE;

ports/stm32/i2cslave.h

@@ -33,10 +33,16 @@ typedef I2C_TypeDef i2c_slave_t;
 void i2c_slave_init_helper(i2c_slave_t *i2c, int addr);
 
 static inline void i2c_slave_init(i2c_slave_t *i2c, int irqn, int irq_pri, int addr) {
-    int en_bit = RCC_APB1ENR_I2C1EN_Pos + ((uintptr_t)i2c - I2C1_BASE) / (I2C2_BASE - I2C1_BASE);
-    RCC->APB1ENR |= 1 << en_bit;
+    int i2c_idx = ((uintptr_t)i2c - I2C1_BASE) / (I2C2_BASE - I2C1_BASE);
+    #if defined(STM32F4) || defined(STM32F7)
+    RCC->APB1ENR |= 1 << (RCC_APB1ENR_I2C1EN_Pos + i2c_idx);
     volatile uint32_t tmp = RCC->APB1ENR; // Delay after enabling clock
     (void)tmp;
+    #elif defined(STM32H7)
+    RCC->APB1LENR |= 1 << (RCC_APB1LENR_I2C1EN_Pos + i2c_idx);
+    volatile uint32_t tmp = RCC->APB1LENR; // Delay after enabling clock
+    (void)tmp;
+    #endif
 
     i2c_slave_init_helper(i2c, addr);