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From: Bich HEMON <bich.hemon@st.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre TORGUE <alexandre.torgue@st.com>,
	"Jiri Slaby" <jslaby@suse.com>,
	"linux-serial@vger.kernel.org" <linux-serial@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Cc: Bich HEMON <bich.hemon@st.com>
Subject: [PATCH 20/20] serial: stm32: fix rx interrupt handling in startup
Date: Mon, 26 Jun 2017 12:49:17 +0000	[thread overview]
Message-ID: <1498481318-1894-21-git-send-email-bich.hemon@st.com> (raw)
In-Reply-To: <1498481318-1894-1-git-send-email-bich.hemon@st.com>

From: Bich Hemon <bich.hemon@st.com>

When stm32 dma is used, Data register has to be read in order
to clear the RXNE interrupt in case we received data before
usart probe.

Signed-off-by: Bich Hemon <bich.hemon@st.com>
---
 drivers/tty/serial/stm32-usart.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 06a92c8..b1f3aab 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -568,9 +568,18 @@ static int stm32_startup(struct uart_port *port)
 	struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
 	struct stm32_usart_config *cfg = &stm32_port->info->cfg;
 	const char *name = to_platform_device(port->dev)->name;
-	u32 val;
+	u32 val, sr, dr;
 	int ret;
 
+	sr = readl_relaxed(port->membase + ofs->isr);
+
+	if ((sr & USART_SR_RXNE) && (stm32_port->rx_ch))
+		ret = readl_relaxed_poll_timeout_atomic(port->membase +
+							ofs->rdr,
+							dr,
+							!(sr & USART_SR_RXNE),
+							10, 100000);
+
 	ret = request_threaded_irq(port->irq, stm32_interrupt,
 				   stm32_threaded_interrupt,
 				   IRQF_NO_SUSPEND, name, port);
-- 
1.9.1

  parent reply	other threads:[~2017-06-26 12:53 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-26 12:49 [PATCH 00/20] Update STM32 usart driver Bich HEMON
2017-06-26 12:49 ` [PATCH 02/20] dt-bindings: serial: each stm32 usart needs an alias Bich HEMON
2017-06-28 18:06   ` Rob Herring
2017-06-26 12:49 ` [PATCH 01/20] serial: stm32: adding fifo support Bich HEMON
2017-06-26 12:49 ` [PATCH 03/20] serial: stm32: fix multi ports management Bich HEMON
2017-06-26 12:49 ` [PATCH 04/20] serial: stm32: make fifoen as property for each port Bich HEMON
2017-06-26 12:49 ` [PATCH 05/20] serial: stm32: add debugfs Bich HEMON
2017-06-26 12:49 ` [PATCH 06/20] serial: stm32: fix pio transmit timeout Bich HEMON
2017-06-26 12:49 ` [PATCH 07/20] serial: stm32: less messages on dma alloc error Bich HEMON
2017-06-26 12:49 ` [PATCH 08/20] serial: stm32: timeout interrupt using with dma Bich HEMON
2017-06-26 12:49 ` [PATCH 10/20] serial: stm32: fix dma receive Bich HEMON
2017-06-26 12:49 ` [PATCH 09/20] serial: stm32: fix end of transfer Bich HEMON
2017-06-26 12:49 ` [PATCH 11/20] serial: stm32: add RTS support Bich HEMON
2017-06-26 12:49 ` [PATCH 12/20] serial: stm32: fix last_res value Bich HEMON
2017-06-26 12:49 ` [PATCH 13/20] serial: stm32: fix error handling in probe Bich HEMON
2017-06-29 14:50   ` Greg Kroah-Hartman
2017-06-26 12:49 ` [PATCH 14/20] dt-bindings: serial: document option wake-up interrupt for STM32 USART Bich HEMON
2017-06-28 18:10   ` Rob Herring
2017-06-29 14:50   ` Greg Kroah-Hartman
2017-06-26 12:49 ` [PATCH 15/20] serial: stm32: Add wakeup mechanism Bich HEMON
2017-06-26 12:49 ` [PATCH 18/20] serial: stm32: update dma buffers length Bich HEMON
2017-06-26 12:49 ` [PATCH 16/20] serial: stm32: fix fifo usage Bich HEMON
2017-06-26 12:49 ` [PATCH 17/20] dt-bindings: serial: stm32: add dma using note Bich HEMON
2017-06-28 22:26   ` Rob Herring
2017-06-29 14:50   ` Greg Kroah-Hartman
2017-06-26 12:49 ` Bich HEMON [this message]
2017-06-26 12:49 ` [PATCH 19/20] serial: stm32: add dma rx callback Bich HEMON
2017-06-29 15:09 ` [PATCH 00/20] Update STM32 usart driver Alexandre Torgue

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