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| author | Fabrice Gasnier <fabrice.gasnier@st.com> | 2019-11-21 09:10:49 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-27 14:46:53 +0100 |
| commit | 7c662630d94fc07da206a8423bfbf9c2330bb2c8 (patch) | |
| tree | 932d3e61d1769a66875202b2804613ad16c9fb10 | |
| parent | 30987a4fd901be1a688feaf4b672d825ceffcd1c (diff) | |
| download | linux-stable-7c662630d94fc07da206a8423bfbf9c2330bb2c8.tar.gz linux-stable-7c662630d94fc07da206a8423bfbf9c2330bb2c8.tar.bz2 linux-stable-7c662630d94fc07da206a8423bfbf9c2330bb2c8.zip | |
serial: stm32: fix clearing interrupt error flags
[ Upstream commit 1250ed7114a977cdc2a67a0c09d6cdda63970eb9 ]
The interrupt clear flag register is a "write 1 to clear" register.
So, only writing ones allows to clear flags:
- Replace buggy stm32_clr_bits() by a simple write to clear error flags
- Replace useless read/modify/write stm32_set_bits() routine by a
simple write to clear TC (transfer complete) flag.
Fixes: 4f01d833fdcd ("serial: stm32: fix rx error handling")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1574323849-1909-1-git-send-email-fabrice.gasnier@st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/tty/serial/stm32-usart.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index f8f3f8fafd9f..1e854e1851fb 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -132,8 +132,8 @@ static void stm32_receive_chars(struct uart_port *port, bool threaded) * cleared by the sequence [read SR - read DR]. */ if ((sr & USART_SR_ERR_MASK) && ofs->icr != UNDEF_REG) - stm32_clr_bits(port, ofs->icr, USART_ICR_ORECF | - USART_ICR_PECF | USART_ICR_FECF); + writel_relaxed(sr & USART_SR_ERR_MASK, + port->membase + ofs->icr); c = stm32_get_char(port, &sr, &stm32_port->last_res); port->icount.rx++; @@ -302,7 +302,7 @@ static void stm32_transmit_chars(struct uart_port *port) if (ofs->icr == UNDEF_REG) stm32_clr_bits(port, ofs->isr, USART_SR_TC); else - stm32_set_bits(port, ofs->icr, USART_ICR_TCCF); + writel_relaxed(USART_ICR_TCCF, port->membase + ofs->icr); if (stm32_port->tx_ch) stm32_transmit_chars_dma(port); |