From: Erwan Le Ray <erwan.leray@foss.st.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jslaby@suse.com>,
Maxime Coquelin <mcoquelin.stm32@gmail.com>,
Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: <linux-serial@vger.kernel.org>,
<linux-stm32@st-md-mailman.stormreply.com>,
<linux-arm-kernel@lists.infradead.org>,
<linux-kernel@vger.kernel.org>,
Erwan Le Ray <erwan.leray@foss.st.com>,
Fabrice Gasnier <fabrice.gasnier@foss.st.com>,
Valentin Caron <valentin.caron@foss.st.com>
Subject: [PATCH v2 13/13] serial: stm32: add support for "flush_buffer" ops
Date: Thu, 4 Mar 2021 17:23:08 +0100 [thread overview]
Message-ID: <20210304162308.8984-14-erwan.leray@foss.st.com> (raw)
In-Reply-To: <20210304162308.8984-1-erwan.leray@foss.st.com>
Add the support for "flush_buffer" ops in order to flush any write buffers,
reset any DMA state and stop any ongoing DMA transfers when the
port->state->xmit circular buffer is cleared.
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 99dfa884cbef..9db6708e3d9f 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -597,6 +597,19 @@ static void stm32_usart_start_tx(struct uart_port *port)
stm32_usart_transmit_chars(port);
}
+/* Flush the transmit buffer. */
+static void stm32_usart_flush_buffer(struct uart_port *port)
+{
+ struct stm32_port *stm32_port = to_stm32_port(port);
+ const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
+
+ if (stm32_port->tx_ch) {
+ dmaengine_terminate_async(stm32_port->tx_ch);
+ stm32_usart_clr_bits(port, ofs->cr3, USART_CR3_DMAT);
+ stm32_port->tx_dma_busy = false;
+ }
+}
+
/* Throttle the remote when input buffer is about to overflow. */
static void stm32_usart_throttle(struct uart_port *port)
{
@@ -992,6 +1005,7 @@ static const struct uart_ops stm32_uart_ops = {
.break_ctl = stm32_usart_break_ctl,
.startup = stm32_usart_startup,
.shutdown = stm32_usart_shutdown,
+ .flush_buffer = stm32_usart_flush_buffer,
.set_termios = stm32_usart_set_termios,
.pm = stm32_usart_pm,
.type = stm32_usart_type,
--
2.17.1
prev parent reply other threads:[~2021-03-04 16:25 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-04 16:22 [PATCH v2 00/13] stm32 usart various fixes Erwan Le Ray
2021-03-04 16:22 ` [PATCH v2 01/13] serial: stm32: fix probe and remove order for dma Erwan Le Ray
2021-03-04 16:22 ` [PATCH v2 02/13] serial: stm32: fix startup by enabling usart for reception Erwan Le Ray
2021-03-04 16:22 ` [PATCH v2 03/13] serial: stm32: fix incorrect characters on console Erwan Le Ray
2021-03-04 16:22 ` [PATCH v2 04/13] serial: stm32: fix TX and RX FIFO thresholds Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 05/13] serial: stm32: fix a deadlock condition with wakeup event Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 06/13] serial: stm32: fix wake-up flag handling Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 07/13] serial: stm32: fix a deadlock in set_termios Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 08/13] serial: stm32: fix tx dma completion, release channel Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 09/13] serial: stm32: call stm32_transmit_chars locked Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 10/13] serial: stm32: fix FIFO flush in startup and set_termios Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 11/13] serial: stm32: add FIFO flush when port is closed Erwan Le Ray
2021-03-04 16:23 ` [PATCH v2 12/13] serial: stm32: fix tx_empty condition Erwan Le Ray
2021-03-04 16:23 ` Erwan Le Ray [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210304162308.8984-14-erwan.leray@foss.st.com \
--to=erwan.leray@foss.st.com \
--cc=alexandre.torgue@foss.st.com \
--cc=fabrice.gasnier@foss.st.com \
--cc=gregkh@linuxfoundation.org \
--cc=jslaby@suse.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
--cc=linux-stm32@st-md-mailman.stormreply.com \
--cc=mcoquelin.stm32@gmail.com \
--cc=valentin.caron@foss.st.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).