linux-kernel - [LINUX PATCH V3 4/9] gpio: gpio-xilinx: Reduce spinlock array to single

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Date:   Thu, 12 Nov 2020 22:42:23 +0530
From:   Srinivas Neeli <srinivas.neeli@...inx.com>
To:     <linus.walleij@...aro.org>, <bgolaszewski@...libre.com>,
        <michal.simek@...inx.com>, <shubhrajyoti.datta@...inx.com>,
        <sgoud@...inx.com>, <hancock@...systems.ca>
CC:     <linux-gpio@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, <git@...inx.com>,
        Srinivas Neeli <srinivas.neeli@...inx.com>
Subject: [LINUX PATCH V3 4/9] gpio: gpio-xilinx: Reduce spinlock array to single

Changed spinlock array to single. It is preparation for irq support which
is shared between two channels that's why spinlock should be only one.

Signed-off-by: Srinivas Neeli <srinivas.neeli@...inx.com>
---
Changes in V3:
-Created new patch for spinlock changes.
---
 drivers/gpio/gpio-xilinx.c | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index 99d603bfb6f0..69bdf1910215 100644
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -47,7 +47,7 @@ struct xgpio_instance {
 	unsigned int gpio_width[2];
 	u32 gpio_state[2];
 	u32 gpio_dir[2];
-	spinlock_t gpio_lock[2];
+	spinlock_t gpio_lock;	/* For serializing operations */
 	struct clk *clk;
 };
 
@@ -113,7 +113,7 @@ static void xgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 	int index =  xgpio_index(chip, gpio);
 	int offset =  xgpio_offset(chip, gpio);
 
-	spin_lock_irqsave(&chip->gpio_lock[index], flags);
+	spin_lock_irqsave(&chip->gpio_lock, flags);
 
 	/* Write to GPIO signal and set its direction to output */
 	if (val)
@@ -124,7 +124,7 @@ static void xgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 	xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
 		       xgpio_regoffset(chip, gpio), chip->gpio_state[index]);
 
-	spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
 }
 
 /**
@@ -148,8 +148,7 @@ static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
 	DECLARE_BITMAP(new, 64);
 	DECLARE_BITMAP(changed, 64);
 
-	spin_lock_irqsave(&chip->gpio_lock[0], flags);
-	spin_lock(&chip->gpio_lock[1]);
+	spin_lock_irqsave(&chip->gpio_lock, flags);
 
 	bitmap_set_value(old, state[0], 0, width[0]);
 	bitmap_set_value(old, state[1], width[0], width[1]);
@@ -170,8 +169,7 @@ static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
 		xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
 				XGPIO_CHANNEL_OFFSET, state[1]);
 
-	spin_unlock(&chip->gpio_lock[1]);
-	spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
 }
 
 /**
@@ -190,14 +188,14 @@ static int xgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 	int index =  xgpio_index(chip, gpio);
 	int offset =  xgpio_offset(chip, gpio);
 
-	spin_lock_irqsave(&chip->gpio_lock[index], flags);
+	spin_lock_irqsave(&chip->gpio_lock, flags);
 
 	/* Set the GPIO bit in shadow register and set direction as input */
 	chip->gpio_dir[index] |= BIT(offset);
 	xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET +
 		       xgpio_regoffset(chip, gpio), chip->gpio_dir[index]);
 
-	spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
 
 	return 0;
 }
@@ -221,7 +219,7 @@ static int xgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 	int index =  xgpio_index(chip, gpio);
 	int offset =  xgpio_offset(chip, gpio);
 
-	spin_lock_irqsave(&chip->gpio_lock[index], flags);
+	spin_lock_irqsave(&chip->gpio_lock, flags);
 
 	/* Write state of GPIO signal */
 	if (val)
@@ -236,7 +234,7 @@ static int xgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 	xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET +
 			xgpio_regoffset(chip, gpio), chip->gpio_dir[index]);
 
-	spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
 
 	return 0;
 }
@@ -294,8 +292,7 @@ static int xgpio_probe(struct platform_device *pdev)
 	if (of_property_read_u32(np, "xlnx,gpio-width", &chip->gpio_width[0]))
 		chip->gpio_width[0] = 32;
 
-	spin_lock_init(&chip->gpio_lock[0]);
-	spin_lock_init(&chip->gpio_lock[1]);
+	spin_lock_init(&chip->gpio_lock);
 
 	if (of_property_read_u32(np, "xlnx,is-dual", &is_dual))
 		is_dual = 0;
-- 
2.7.4