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| author | Erwan Le Ray <erwan.leray@st.com> | 2019-06-18 12:02:26 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-21 11:17:36 +0200 |
| commit | 84872dc448fe0ae11fe8412f4966e9c431a45b8f (patch) | |
| tree | 38c487121a9a239cfdee11211fd0cfe600a0dc29 /drivers | |
| parent | d0a6a7bcc3fa0e97efce1d9a5c4cca6f3474c6bb (diff) | |
| download | blackbird-op-linux-84872dc448fe0ae11fe8412f4966e9c431a45b8f.tar.gz blackbird-op-linux-84872dc448fe0ae11fe8412f4966e9c431a45b8f.zip | |
serial: stm32: add RX and TX FIFO flush
Adds a flush of RX and TX FIFOs, and fixes some errors:
- adds RX FIFO flush in startup fonction
- removes the useless transmitter enabling in startup fonction
(e.g. receiver only, see Documentation/serial/driver)
- configures FIFO threshold before enabling it, rather than after
- flushes both TX and RX in set_termios function
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/tty/serial/stm32-usart.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index fd9fb33ce4fe..24a2261f879a 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -599,11 +599,11 @@ static int stm32_startup(struct uart_port *port) if (ret) return ret; - val = stm32_port->cr1_irq | USART_CR1_TE | USART_CR1_RE; - if (stm32_port->fifoen) - val |= USART_CR1_FIFOEN; - stm32_set_bits(port, ofs->cr1, val); + /* RX FIFO Flush */ + if (ofs->rqr != UNDEF_REG) + stm32_set_bits(port, ofs->rqr, USART_RQR_RXFRQ); + /* Tx and RX FIFO configuration */ if (stm32_port->fifoen) { val = readl_relaxed(port->membase + ofs->cr3); val &= ~(USART_CR3_TXFTCFG_MASK | USART_CR3_RXFTCFG_MASK); @@ -612,6 +612,12 @@ static int stm32_startup(struct uart_port *port) writel_relaxed(val, port->membase + ofs->cr3); } + /* RX FIFO enabling */ + val = stm32_port->cr1_irq | USART_CR1_RE; + if (stm32_port->fifoen) + val |= USART_CR1_FIFOEN; + stm32_set_bits(port, ofs->cr1, val); + return 0; } @@ -694,8 +700,12 @@ static void stm32_set_termios(struct uart_port *port, struct ktermios *termios, /* Stop serial port and reset value */ writel_relaxed(0, port->membase + ofs->cr1); - cr1 = USART_CR1_TE | USART_CR1_RE; + /* flush RX & TX FIFO */ + if (ofs->rqr != UNDEF_REG) + stm32_set_bits(port, ofs->rqr, + USART_RQR_TXFRQ | USART_RQR_RXFRQ); + cr1 = USART_CR1_TE | USART_CR1_RE; if (stm32_port->fifoen) cr1 |= USART_CR1_FIFOEN; cr2 = 0; |
