void gpio_port_config_lock(u32 gpioport, u16 gpios)
{
u32 reg32;
/* Special "Lock Key Writing Sequence", see datasheet. */
GPIO_LCKR(gpioport) = GPIO_LCKK | gpios; /* Set LCKK. */
GPIO_LCKR(gpioport) = ~GPIO_LCKK & gpios; /* Clear LCKK. */
GPIO_LCKR(gpioport) = GPIO_LCKK | gpios; /* Set LCKK. */
reg32 = GPIO_LCKR(gpioport); /* Read LCKK. */
reg32 = GPIO_LCKR(gpioport); /* Read LCKK again. */
/* If (reg32 & GPIO_LCKK) is true, the lock is now active. */
}
/** @brief Lock the Configuration of a Group of Pins
The configuration of one or more pins of the given GPIO port is locked. There is
no mechanism to unlock these via software. Unlocking occurs at the next reset.
@param[in] gpioport Unsigned int32. Port identifier @ref gpio_port_id
@param[in] gpios Unsigned int16. Pin identifiers @ref gpio_pin_id
If multiple pins are to be locked, use logical OR '|' to separate them.
*/
void gpio_port_config_lock(u32 gpioport, u16 gpios)
{
u32 reg32;
/* Special "Lock Key Writing Sequence", see datasheet. */
GPIO_LCKR(gpioport) = GPIO_LCKK | gpios; /* Set LCKK. */
GPIO_LCKR(gpioport) = ~GPIO_LCKK & gpios; /* Clear LCKK. */
GPIO_LCKR(gpioport) = GPIO_LCKK | gpios; /* Set LCKK. */
reg32 = GPIO_LCKR(gpioport); /* Read LCKK. */
reg32 = GPIO_LCKR(gpioport); /* Read LCKK again. */
/* Tell the compiler the variable is actually used. It will get optimized out anyways. */
reg32 = reg32;
/* If (reg32 & GPIO_LCKK) is true, the lock is now active. */
}
