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| author | Erwan Le Ray <erwan.leray@st.com> | 2019-05-21 18:45:43 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-24 10:58:29 +0300 |
| commit | 6c5962f30bce147b1c83869085f3ddde3b34c9e3 (patch) | |
| tree | 271cb4b5f46d1756134c5fd5a6894b9b35aa5691 /drivers/tty/serial/stm32-usart.c | |
| parent | 4f01d833fdcdd6f9b85d9e5d5d7568eb683626a7 (diff) | |
| download | linux-6c5962f30bce147b1c83869085f3ddde3b34c9e3.tar.xz | |
serial: stm32: fix rx data length when parity enabled
- Fixes a rx data error when data length < 8 bits and parity is enabled.
RDR register MSB is used for parity bit reception.
- Adds a mask to ignore MSB when data is get from RDR.
Fixes: 3489187204eb ("serial: stm32: adding dma support")
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/stm32-usart.c')
| -rw-r--r-- | drivers/tty/serial/stm32-usart.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index f6b739351dde..0a7953e5ce47 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -194,8 +194,8 @@ static int stm32_pending_rx(struct uart_port *port, u32 *sr, int *last_res, return 0; } -static unsigned long -stm32_get_char(struct uart_port *port, u32 *sr, int *last_res) +static unsigned long stm32_get_char(struct uart_port *port, u32 *sr, + int *last_res) { struct stm32_port *stm32_port = to_stm32_port(port); struct stm32_usart_offsets *ofs = &stm32_port->info->ofs; @@ -205,10 +205,13 @@ stm32_get_char(struct uart_port *port, u32 *sr, int *last_res) c = stm32_port->rx_buf[RX_BUF_L - (*last_res)--]; if ((*last_res) == 0) *last_res = RX_BUF_L; - return c; } else { - return readl_relaxed(port->membase + ofs->rdr); + c = readl_relaxed(port->membase + ofs->rdr); + /* apply RDR data mask */ + c &= stm32_port->rdr_mask; } + + return c; } static void stm32_receive_chars(struct uart_port *port, bool threaded) @@ -679,6 +682,7 @@ static void stm32_set_termios(struct uart_port *port, struct ktermios *termios, cr2 |= USART_CR2_STOP_2B; bits = stm32_get_databits(termios); + stm32_port->rdr_mask = (BIT(bits) - 1); if (cflag & PARENB) { bits++; |