diff options
Diffstat (limited to 'src/drivers/uart/util.c')
| -rw-r--r-- | src/drivers/uart/util.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/src/drivers/uart/util.c b/src/drivers/uart/util.c index 4121f60852..5e8d223252 100644 --- a/src/drivers/uart/util.c +++ b/src/drivers/uart/util.c @@ -42,3 +42,20 @@ unsigned int uart_baudrate_divisor(unsigned int baudrate, { return (1 + (2 * refclk) / (baudrate * oversample)) / 2; } + +#if !IS_ENABLED(CONFIG_UART_OVERRIDE_INPUT_CLOCK_DIVIDER) +unsigned int uart_input_clock_divider(void) +{ + /* Specify the default oversample rate for the UART. + * + * UARTs oversample the receive data. The UART's input clock first + * enters the baud-rate divider to generate the oversample clock. Then + * the UART typically divides the result by 16. The asynchronous + * receive data is synchronized with the oversample clock and when a + * start bit is detected the UART delays half a bit time using the + * oversample clock. Samples are then taken to verify the start bit and + * if present, samples are taken for the rest of the frame. + */ + return 16; +} +#endif |