drivers: serial: stm32: prevent stop/data-bits HW support code duplication
Preventing code duplication of macros checking for HW support on
stop bits and data-bits during runtime configuration.
Validated runtime configuration on an STM32H743.
Signed-off-by: Jeroen van Dooren <jeroen.van.dooren@nobleo.nl>
diff --git a/drivers/serial/uart_stm32.c b/drivers/serial/uart_stm32.c
index 4b19fb2..c02ac85 100644
--- a/drivers/serial/uart_stm32.c
+++ b/drivers/serial/uart_stm32.c
@@ -310,12 +310,19 @@
}
}
-static inline uint32_t uart_stm32_cfg2ll_stopbits(enum uart_config_stop_bits sb)
+static inline uint32_t uart_stm32_cfg2ll_stopbits(const struct uart_stm32_config *config,
+ enum uart_config_stop_bits sb)
{
switch (sb) {
/* Some MCU's don't support 0.5 stop bits */
#ifdef LL_USART_STOPBITS_0_5
case UART_CFG_STOP_BITS_0_5:
+#if HAS_LPUART_1
+ if (IS_LPUART_INSTANCE(config->usart)) {
+ /* return the default */
+ return LL_USART_STOPBITS_1;
+ }
+#endif /* HAS_LPUART_1 */
return LL_USART_STOPBITS_0_5;
#endif /* LL_USART_STOPBITS_0_5 */
case UART_CFG_STOP_BITS_1:
@@ -323,6 +330,12 @@
/* Some MCU's don't support 1.5 stop bits */
#ifdef LL_USART_STOPBITS_1_5
case UART_CFG_STOP_BITS_1_5:
+#if HAS_LPUART_1
+ if (IS_LPUART_INSTANCE(config->usart)) {
+ /* return the default */
+ return LL_USART_STOPBITS_2;
+ }
+#endif
return LL_USART_STOPBITS_1_5;
#endif /* LL_USART_STOPBITS_1_5 */
case UART_CFG_STOP_BITS_2:
@@ -455,7 +468,7 @@
const struct uart_stm32_config *config = dev->config;
struct uart_stm32_data *data = dev->data;
const uint32_t parity = uart_stm32_cfg2ll_parity(cfg->parity);
- const uint32_t stopbits = uart_stm32_cfg2ll_stopbits(cfg->stop_bits);
+ const uint32_t stopbits = uart_stm32_cfg2ll_stopbits(config, cfg->stop_bits);
const uint32_t databits = uart_stm32_cfg2ll_databits(cfg->data_bits,
cfg->parity);
const uint32_t flowctrl = uart_stm32_cfg2ll_hwctrl(cfg->flow_ctrl);
@@ -475,35 +488,17 @@
return -ENOTSUP;
}
-#if defined(LL_USART_STOPBITS_0_5) && HAS_LPUART_1
- if (IS_LPUART_INSTANCE(config->usart) &&
- (cfg->stop_bits == UART_CFG_STOP_BITS_0_5)) {
+ /* When the transformed ll stop bits don't match with what was requested, then it's not
+ * supported
+ */
+ if (uart_stm32_ll2cfg_stopbits(stopbits) != cfg->stop_bits) {
return -ENOTSUP;
}
-#else
- if (cfg->stop_bits == UART_CFG_STOP_BITS_0_5) {
- return -ENOTSUP;
- }
-#endif
-#if defined(LL_USART_STOPBITS_1_5) && HAS_LPUART_1
- if (IS_LPUART_INSTANCE(config->usart) &&
- (cfg->stop_bits == UART_CFG_STOP_BITS_1_5)) {
- return -ENOTSUP;
- }
-#else
- if (cfg->stop_bits == UART_CFG_STOP_BITS_1_5) {
- return -ENOTSUP;
- }
-#endif
-
- /* Driver doesn't support 5 or 6 databits and potentially 7 or 9 */
- if ((cfg->data_bits == UART_CFG_DATA_BITS_5) ||
- (cfg->data_bits == UART_CFG_DATA_BITS_6)
-#ifndef LL_USART_DATAWIDTH_7B
- || (cfg->data_bits == UART_CFG_DATA_BITS_7)
-#endif /* LL_USART_DATAWIDTH_7B */
- || (cfg->data_bits == UART_CFG_DATA_BITS_9)) {
+ /* When the transformed ll databits don't match with what was requested, then it's not
+ * supported
+ */
+ if (uart_stm32_ll2cfg_databits(databits, parity) != cfg->data_bits) {
return -ENOTSUP;
}
