linux-kernel - [PATCH v2 04/11] i2c: nomadik: simplify IRQ masking logic

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Message-Id: <20240229-mbly-i2c-v2-4-b32ed18c098c@bootlin.com>
Date: Thu, 29 Feb 2024 19:10:52 +0100
From: Théo Lebrun <theo.lebrun@...tlin.com>
To: Linus Walleij <linus.walleij@...aro.org>, 
 Andi Shyti <andi.shyti@...nel.org>, Rob Herring <robh+dt@...nel.org>, 
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>, 
 Conor Dooley <conor+dt@...nel.org>, 
 Thomas Bogendoerfer <tsbogend@...ha.franken.de>
Cc: linux-arm-kernel@...ts.infradead.org, linux-i2c@...r.kernel.org, 
 devicetree@...r.kernel.org, linux-kernel@...r.kernel.org, 
 linux-mips@...r.kernel.org, Gregory Clement <gregory.clement@...tlin.com>, 
 Vladimir Kondratiev <vladimir.kondratiev@...ileye.com>, 
 Thomas Petazzoni <thomas.petazzoni@...tlin.com>, 
 Tawfik Bayouk <tawfik.bayouk@...ileye.com>, 
 Théo Lebrun <theo.lebrun@...tlin.com>
Subject: [PATCH v2 04/11] i2c: nomadik: simplify IRQ masking logic

IRQ_MASK and I2C_CLEAR_ALL_INTS are redundant. One masks the top three
bits off as reserved, the other one masks the reserved IRQs inside the
u32. Get rid of IRQ_MASK and only use the most restrictive mask.

Reviewed-by: Linus Walleij <linus.walleij@...aro.org>
Signed-off-by: Théo Lebrun <theo.lebrun@...tlin.com>
---
 drivers/i2c/busses/i2c-nomadik.c | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index cd511c884f99..80bdf7e42613 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -94,9 +94,6 @@
 /* some bits in ICR are reserved */
 #define I2C_CLEAR_ALL_INTS	0x131f007f
 
-/* first three msb bits are reserved */
-#define IRQ_MASK(mask)		(mask & 0x1fffffff)
-
 /* maximum threshold value */
 #define MAX_I2C_FIFO_THRESHOLD	15
 
@@ -249,8 +246,7 @@ static int flush_i2c_fifo(struct nmk_i2c_dev *priv)
  */
 static void disable_all_interrupts(struct nmk_i2c_dev *priv)
 {
-	u32 mask = IRQ_MASK(0);
-	writel(mask, priv->virtbase + I2C_IMSCR);
+	writel(0, priv->virtbase + I2C_IMSCR);
 }
 
 /**
@@ -259,9 +255,7 @@ static void disable_all_interrupts(struct nmk_i2c_dev *priv)
  */
 static void clear_all_interrupts(struct nmk_i2c_dev *priv)
 {
-	u32 mask;
-	mask = IRQ_MASK(I2C_CLEAR_ALL_INTS);
-	writel(mask, priv->virtbase + I2C_ICR);
+	writel(I2C_CLEAR_ALL_INTS, priv->virtbase + I2C_ICR);
 }
 
 /**
@@ -468,7 +462,7 @@ static int read_i2c(struct nmk_i2c_dev *priv, u16 flags)
 	else
 		irq_mask |= I2C_IT_MTDWS;
 
-	irq_mask = I2C_CLEAR_ALL_INTS & IRQ_MASK(irq_mask);
+	irq_mask &= I2C_CLEAR_ALL_INTS;
 
 	writel(readl(priv->virtbase + I2C_IMSCR) | irq_mask,
 	       priv->virtbase + I2C_IMSCR);
@@ -547,7 +541,7 @@ static int write_i2c(struct nmk_i2c_dev *priv, u16 flags)
 	else
 		irq_mask |= I2C_IT_MTDWS;
 
-	irq_mask = I2C_CLEAR_ALL_INTS & IRQ_MASK(irq_mask);
+	irq_mask &= I2C_CLEAR_ALL_INTS;
 
 	writel(readl(priv->virtbase + I2C_IMSCR) | irq_mask,
 	       priv->virtbase + I2C_IMSCR);
@@ -703,8 +697,8 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
  */
 static int disable_interrupts(struct nmk_i2c_dev *priv, u32 irq)
 {
-	irq = IRQ_MASK(irq);
-	writel(readl(priv->virtbase + I2C_IMSCR) & ~(I2C_CLEAR_ALL_INTS & irq),
+	irq &= I2C_CLEAR_ALL_INTS;
+	writel(readl(priv->virtbase + I2C_IMSCR) & ~irq,
 	       priv->virtbase + I2C_IMSCR);
 	return 0;
 }

-- 
2.44.0