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spin_lock instead of spin_lock_irqsave in imx uart interuput

PATCH QIANJUN 2 participants 2 messages Aug 26, 2018

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Arm i.MX and Layerscape TTY layer and serial drivers
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QIANJUN

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#0 lore raw

spin_lock instead of spin_lock_irqsave in imx uart interuput

Quoted 1 line

From 6580790d7be51a78d1376b90df49b04019a1f944 Mon Sep 17 00:00:00 2001

From: jun qian <[email protected]>
Date: Sun, 26 Aug 2018 06:58:35 -0700
Subject: [PATCH] before the programe into the uart interuput's handler, the
system has already disabled the local cpu interuput. so the spin_lock interface is More suitable for here.

Signed-off-by jun qian <[email protected]>
---
 drivers/tty/serial/imx.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)
drivers/tty/serial/imx.c +8 -13
index 239c0fa2e981..3069ee93583e 100644
@@ -706,27 +706,25 @@ static irqreturn_t imx_uart_rtsint(int irq, void *dev_id)
 {
 	struct imx_port *sport = dev_id;
 	u32 usr1;
-	unsigned long flags;
 
-	spin_lock_irqsave(&sport->port.lock, flags);
+	spin_lock(&sport->port.lock);
 
 	imx_uart_writel(sport, USR1_RTSD, USR1);
 	usr1 = imx_uart_readl(sport, USR1) & USR1_RTSS;
 	uart_handle_cts_change(&sport->port, !!usr1);
 	wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
 
-	spin_unlock_irqrestore(&sport->port.lock, flags);
+	spin_unlock(&sport->port.lock);
 	return IRQ_HANDLED;
 }
 
 static irqreturn_t imx_uart_txint(int irq, void *dev_id)
 {
 	struct imx_port *sport = dev_id;
-	unsigned long flags;
 
-	spin_lock_irqsave(&sport->port.lock, flags);
+	spin_lock(&sport->port.lock);
 	imx_uart_transmit_buffer(sport);
-	spin_unlock_irqrestore(&sport->port.lock, flags);
+	spin_unlock(&sport->port.lock);
 	return IRQ_HANDLED;
 }
 

@@ -735,9 +733,8 @@ static irqreturn_t imx_uart_rxint(int irq, void *dev_id)
 	struct imx_port *sport = dev_id;
 	unsigned int rx, flg, ignored = 0;
 	struct tty_port *port = &sport->port.state->port;
-	unsigned long flags;
 
-	spin_lock_irqsave(&sport->port.lock, flags);
+	spin_lock(&sport->port.lock);
 
 	while (imx_uart_readl(sport, USR2) & USR2_RDR) {
 		u32 usr2;

@@ -797,7 +794,7 @@ static irqreturn_t imx_uart_rxint(int irq, void *dev_id)
 	}
 
 out:
-	spin_unlock_irqrestore(&sport->port.lock, flags);
+	spin_unlock(&sport->port.lock);
 	tty_flip_buffer_push(port);
 	return IRQ_HANDLED;
 }

@@ -903,13 +900,11 @@ static irqreturn_t imx_uart_int(int irq, void *dev_id)
 	}
 
 	if (usr1 & USR1_DTRD) {
-		unsigned long flags;
-
 		imx_uart_writel(sport, USR1_DTRD, USR1);
 
-		spin_lock_irqsave(&sport->port.lock, flags);
+		spin_lock(&sport->port.lock);
 		imx_uart_mctrl_check(sport);
-		spin_unlock_irqrestore(&sport->port.lock, flags);
+		spin_unlock(&sport->port.lock);
 
 		ret = IRQ_HANDLED;
 	}
Signature · 1 line
2.17.1
maintainer
#1 lore raw
Quoted 1 line · QIANJUN

spin_lock instead of spin_lock_irqsave in imx uart interuput

What does that mean?

Quoted 6 lines
Quoted 1 line

From 6580790d7be51a78d1376b90df49b04019a1f944 Mon Sep 17 00:00:00 2001

From: jun qian <[email protected]>
Date: Sun, 26 Aug 2018 06:58:35 -0700
Subject: [PATCH] before the programe into the uart interuput's handler, the
system has already disabled the local cpu interuput. so the spin_lock interface is More suitable for here.

Why is this here? The changelog text belongs in the changelog, not in the subject line :(

can you fix this all up and resend?

thanks,

greg k-h