From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A0E961868 for ; Wed, 28 Dec 2022 15:27:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2524CC433F0; Wed, 28 Dec 2022 15:27:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672241253; bh=d5AT1t18jRg+EHlRlDa4fgW/bB1AD/80ldiTVQYxRzc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wWmAcxt3sqyCeE/SshUE5JZ9X/sw36I2Bvd9zMY5KsirZAu1tPeYfjmE/4/AHjRjs 3uB3aUGERstwlDbraW15CE9BdmCTtnsABSdF2zmZJabXakdqGpKcWBcRVVbXWs7qAz zn1hzYUc6tBjs5z6itOvhcx34cU7Ppcx1Z1Q6XsE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, delisun , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Sasha Levin Subject: [PATCH 5.15 458/731] serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle. Date: Wed, 28 Dec 2022 15:39:25 +0100 Message-Id: <20221228144309.829191330@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144256.536395940@linuxfoundation.org> References: <20221228144256.536395940@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: delisun [ Upstream commit 032d5a71ed378ffc6a2d41a187d8488a4f9fe415 ] Clearing the RX FIFO will cause data loss. Copy the pl011_enabl_interrupts implementation, and remove the clear interrupt and FIFO part of the code. Fixes: 211565b10099 ("serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle") Signed-off-by: delisun Reviewed-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20221110020108.7700-1-delisun@pateo.com.cn Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/amba-pl011.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index ca105e9baa42..7c8515f83f0a 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1836,8 +1836,17 @@ static void pl011_enable_interrupts(struct uart_amba_port *uap) static void pl011_unthrottle_rx(struct uart_port *port) { struct uart_amba_port *uap = container_of(port, struct uart_amba_port, port); + unsigned long flags; - pl011_enable_interrupts(uap); + spin_lock_irqsave(&uap->port.lock, flags); + + uap->im = UART011_RTIM; + if (!pl011_dma_rx_running(uap)) + uap->im |= UART011_RXIM; + + pl011_write(uap->im, uap, REG_IMSC); + + spin_unlock_irqrestore(&uap->port.lock, flags); } static int pl011_startup(struct uart_port *port) -- 2.35.1