Skip to content

drivers: serial: stm32: return error for bad baud #92119

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
+48 −16
Open

drivers: serial: stm32: return error for bad baud #92119

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
64 changes: 48 additions & 16 deletions drivers/serial/uart_stm32.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -140,28 +140,34 @@ static void uart_stm32_pm_policy_state_lock_put(const struct device *dev)
}
#endif /* CONFIG_PM */

static inline void uart_stm32_set_baudrate(const struct device *dev, uint32_t baud_rate)
static inline int uart_stm32_set_baudrate(const struct device *dev, uint32_t baud_rate)
{
const struct uart_stm32_config *config = dev->config;
USART_TypeDef *usart = config->usart;
struct uart_stm32_data *data = dev->data;

if (baud_rate == 0) {
return -EINVAL;
}

uint32_t clock_rate;

/* Get clock rate */
if (IS_ENABLED(STM32_UART_DOMAIN_CLOCK_SUPPORT) && (config->pclk_len > 1)) {
if (clock_control_get_rate(data->clock,
(clock_control_subsys_t)&config->pclken[1],
&clock_rate) < 0) {
int ret = clock_control_get_rate(data->clock,
(clock_control_subsys_t)&config->pclken[1],
&clock_rate);
if (ret < 0) {
LOG_ERR("Failed call clock_control_get_rate(pclken[1])");
return;
return ret;
}
} else {
if (clock_control_get_rate(data->clock,
(clock_control_subsys_t)&config->pclken[0],
&clock_rate) < 0) {
int ret = clock_control_get_rate(data->clock,
(clock_control_subsys_t)&config->pclken[0],
&clock_rate);
if (ret < 0) {
LOG_ERR("Failed call clock_control_get_rate(pclken[0])");
return;
return ret;
}
}

Expand All @@ -181,7 +187,7 @@ static inline void uart_stm32_set_baudrate(const struct device *dev, uint32_t ba

if (presc_idx == ARRAY_SIZE(LPUART_PRESCALER_TAB)) {
LOG_ERR("Unable to set %s to %d", dev->name, baud_rate);
return;
return -EINVAL;
}

presc_val = presc_idx << USART_PRESC_PRESCALER_Pos;
Expand All @@ -191,7 +197,7 @@ static inline void uart_stm32_set_baudrate(const struct device *dev, uint32_t ba
lpuartdiv = lpuartdiv_calc(clock_rate, baud_rate);
if (lpuartdiv < LPUART_BRR_MIN_VALUE || lpuartdiv > LPUART_BRR_MASK) {
LOG_ERR("Unable to set %s to %d", dev->name, baud_rate);
return;
return -EINVAL;
}
#endif /* USART_PRESC_PRESCALER */
LL_LPUART_SetBaudRate(usart,
Expand All @@ -213,6 +219,17 @@ static inline void uart_stm32_set_baudrate(const struct device *dev, uint32_t ba
LL_USART_SetOverSampling(usart,
LL_USART_OVERSAMPLING_16);
#endif

uint32_t usartdiv = __LL_USART_DIV_SAMPLING16(clock_rate,
#ifdef USART_PRESC_PRESCALER
LL_USART_PRESCALER_DIV1,
#endif
baud_rate);
if (usartdiv < 16) {
LOG_ERR("Unable to set %s to %d", dev->name, baud_rate);
return -EINVAL;
}

LL_USART_SetBaudRate(usart,
clock_rate,
#ifdef USART_PRESC_PRESCALER
Expand All @@ -229,6 +246,8 @@ static inline void uart_stm32_set_baudrate(const struct device *dev, uint32_t ba
#if HAS_LPUART
}
#endif /* HAS_LPUART */

return 0;
}

static inline void uart_stm32_set_parity(const struct device *dev,
Expand Down Expand Up @@ -487,7 +506,7 @@ static inline enum uart_config_flow_control uart_stm32_ll2cfg_hwctrl(uint32_t fc
return UART_CFG_FLOW_CTRL_NONE;
}

static void uart_stm32_parameters_set(const struct device *dev,
static int uart_stm32_parameters_set(const struct device *dev,
const struct uart_config *cfg)
{
const struct uart_stm32_config *config = dev->config;
Expand All @@ -501,6 +520,7 @@ static void uart_stm32_parameters_set(const struct device *dev,
#if HAS_DRIVER_ENABLE
bool driver_enable = cfg->flow_ctrl == UART_CFG_FLOW_CTRL_RS485;
#endif
int ret = 0;

if (cfg == uart_cfg) {
/* Called via (re-)init function, so the SoC either just booted,
Expand All @@ -512,7 +532,10 @@ static void uart_stm32_parameters_set(const struct device *dev,
parity,
stopbits);
uart_stm32_set_hwctrl(dev, flowctrl);
uart_stm32_set_baudrate(dev, cfg->baudrate);
ret = uart_stm32_set_baudrate(dev, cfg->baudrate);
if (ret < 0) {
return ret;
}
} else {
/* Called from application/subsys via uart_configure syscall */
if (parity != uart_stm32_get_parity(dev)) {
Expand All @@ -538,10 +561,15 @@ static void uart_stm32_parameters_set(const struct device *dev,
#endif

if (cfg->baudrate != uart_cfg->baudrate) {
uart_stm32_set_baudrate(dev, cfg->baudrate);
ret = uart_stm32_set_baudrate(dev, cfg->baudrate);
if (ret < 0) {
return ret;
}
uart_cfg->baudrate = cfg->baudrate;
}
}

return 0;
}

#ifdef CONFIG_UART_USE_RUNTIME_CONFIGURE
Expand Down Expand Up @@ -598,7 +626,9 @@ static int uart_stm32_configure(const struct device *dev,
LL_USART_Disable(usart);

/* Set basic parameters, such as data-/stop-bit, parity, and baudrate */
uart_stm32_parameters_set(dev, cfg);
if (uart_stm32_parameters_set(dev, cfg) < 0) {
return -ENOTSUP;
}

LL_USART_Enable(usart);

Expand Down Expand Up @@ -2090,7 +2120,9 @@ static int uart_stm32_registers_configure(const struct device *dev)
LL_USART_SetTransferDirection(usart, LL_USART_DIRECTION_TX_RX);

/* Set basic parameters, such as data-/stop-bit, parity, and baudrate */
uart_stm32_parameters_set(dev, uart_cfg);
if (uart_stm32_parameters_set(dev, uart_cfg) < 0) {
return -EINVAL;
}

/* Enable the single wire / half-duplex mode */
if (config->single_wire) {
Expand Down