diff mbox series

[v4,3/3] gpio: xilinx: Utilize generic bitmap_get_value and _set_value

Message ID 00d085d4068be651c58a61564926d4f3d495ab80.1617357235.git.syednwaris@gmail.com (mailing list archive)
State New, archived
Headers show
Series Introduce the for_each_set_nbits macro | expand

Commit Message

Syed Nayyar Waris April 2, 2021, 10:12 a.m. UTC 
This patch reimplements the xgpio_set_multiple() function in
drivers/gpio/gpio-xilinx.c to use the new generic functions:
bitmap_get_value() and bitmap_set_value(). The code is now simpler
to read and understand. Moreover, instead of looping for each bit
in xgpio_set_multiple() function, now we can check each channel at
a time and save cycles.

Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Syed Nayyar Waris <syednwaris@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
 drivers/gpio/gpio-xilinx.c | 60 +++++++++++++++++++-------------------
 1 file changed, 30 insertions(+), 30 deletions(-)

Comments

Syed Nayyar Waris April 2, 2021, 4:34 p.m. UTC | #1 
On Fri, Apr 2, 2021 at 3:42 PM Syed Nayyar Waris <syednwaris@gmail.com> wrote:
>
> This patch reimplements the xgpio_set_multiple() function in
> drivers/gpio/gpio-xilinx.c to use the new generic functions:
> bitmap_get_value() and bitmap_set_value(). The code is now simpler
> to read and understand. Moreover, instead of looping for each bit
> in xgpio_set_multiple() function, now we can check each channel at
> a time and save cycles.
>
> Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> Cc: Michal Simek <michal.simek@xilinx.com>
> Signed-off-by: Syed Nayyar Waris <syednwaris@gmail.com>
> Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
> ---
>  drivers/gpio/gpio-xilinx.c | 60 +++++++++++++++++++-------------------
>  1 file changed, 30 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> index b411d3156e0b..e0ad3a81f216 100644
> --- a/drivers/gpio/gpio-xilinx.c
> +++ b/drivers/gpio/gpio-xilinx.c
> @@ -18,6 +18,7 @@
>  #include <linux/of_platform.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/slab.h>
> +#include "gpiolib.h"
>
>  /* Register Offset Definitions */
>  #define XGPIO_DATA_OFFSET   (0x0)      /* Data register  */
> @@ -161,37 +162,36 @@ static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
>  {
>         unsigned long flags;
>         struct xgpio_instance *chip = gpiochip_get_data(gc);
> -       int index = xgpio_index(chip, 0);
> -       int offset, i;
>
> -       spin_lock_irqsave(&chip->gpio_lock, flags);
> -
> -       /* Write to GPIO signals */
> -       for (i = 0; i < gc->ngpio; i++) {
> -               if (*mask == 0)
> -                       break;
> -               /* Once finished with an index write it out to the register */
> -               if (index !=  xgpio_index(chip, i)) {
> -                       xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
> -                                      index * XGPIO_CHANNEL_OFFSET,
> -                                      chip->gpio_state[index]);
> -                       spin_unlock_irqrestore(&chip->gpio_lock, flags);
> -                       index =  xgpio_index(chip, i);
> -                       spin_lock_irqsave(&chip->gpio_lock, flags);
> -               }
> -               if (__test_and_clear_bit(i, mask)) {
> -                       offset =  xgpio_offset(chip, i);
> -                       if (test_bit(i, bits))
> -                               chip->gpio_state[index] |= BIT(offset);
> -                       else
> -                               chip->gpio_state[index] &= ~BIT(offset);
> -               }
> -       }
> -
> -       xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
> -                      index * XGPIO_CHANNEL_OFFSET, chip->gpio_state[index]);
> -
> -       spin_unlock_irqrestore(&chip->gpio_lock, flags);
> +    u32 *state = chip->gpio_state;
> +    unsigned int *width = chip->gpio_width;
> +    DECLARE_BITMAP(old, 64);
> +    DECLARE_BITMAP(new, 64);
> +    DECLARE_BITMAP(changed, 64);
> +
> +    spin_lock_irqsave(&chip->gpio_lock, flags);
> +
> +    /* Copy initial value of state bits into 'old' bit-wise */
> +    bitmap_set_value(old, 64, state[0], width[0], 0);
> +    bitmap_set_value(old, 64, state[1], width[1], width[0]);
> +    /* Copy value from 'old' into 'new' with mask applied */
> +    bitmap_replace(new, old, bits, mask, gc->ngpio);
> +
> +    bitmap_from_arr32(old, state, 64);
> +    /* Update 'state' */
> +    state[0] = bitmap_get_value(new, 0, width[0]);
> +    state[1] = bitmap_get_value(new, width[0], width[1]);
> +    bitmap_from_arr32(new, state, 64);
> +    /* XOR operation sets only changed bits */
> +    bitmap_xor(changed, old, new, 64);
> +
> +    if (((u32 *)changed)[0])
> +        xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET, state[0]);
> +    if (((u32 *)changed)[1])
> +        xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
> +                XGPIO_CHANNEL_OFFSET, state[1]);
> +
> +    spin_unlock_irqrestore(&chip->gpio_lock, flags);
>  }
>
>  /**
> --
> 2.29.0
>

Hi All,

There were indentation errors reported. I am Re-sending the patchset.
I am keeping the version same as v4.

Kindly consider the "RESEND" prefixed v4 patchset for future.

Regards
Syed Nayyar Waris
diff mbox series

Patch

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index b411d3156e0b..e0ad3a81f216 100644
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -18,6 +18,7 @@ 
 #include <linux/of_platform.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
+#include "gpiolib.h"
 
 /* Register Offset Definitions */
 #define XGPIO_DATA_OFFSET   (0x0)	/* Data register  */
@@ -161,37 +162,36 @@  static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
 {
 	unsigned long flags;
 	struct xgpio_instance *chip = gpiochip_get_data(gc);
-	int index = xgpio_index(chip, 0);
-	int offset, i;
 
-	spin_lock_irqsave(&chip->gpio_lock, flags);
-
-	/* Write to GPIO signals */
-	for (i = 0; i < gc->ngpio; i++) {
-		if (*mask == 0)
-			break;
-		/* Once finished with an index write it out to the register */
-		if (index !=  xgpio_index(chip, i)) {
-			xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
-				       index * XGPIO_CHANNEL_OFFSET,
-				       chip->gpio_state[index]);
-			spin_unlock_irqrestore(&chip->gpio_lock, flags);
-			index =  xgpio_index(chip, i);
-			spin_lock_irqsave(&chip->gpio_lock, flags);
-		}
-		if (__test_and_clear_bit(i, mask)) {
-			offset =  xgpio_offset(chip, i);
-			if (test_bit(i, bits))
-				chip->gpio_state[index] |= BIT(offset);
-			else
-				chip->gpio_state[index] &= ~BIT(offset);
-		}
-	}
-
-	xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
-		       index * XGPIO_CHANNEL_OFFSET, chip->gpio_state[index]);
-
-	spin_unlock_irqrestore(&chip->gpio_lock, flags);
+    u32 *state = chip->gpio_state;
+    unsigned int *width = chip->gpio_width;
+    DECLARE_BITMAP(old, 64);
+    DECLARE_BITMAP(new, 64);
+    DECLARE_BITMAP(changed, 64);
+
+    spin_lock_irqsave(&chip->gpio_lock, flags);
+
+    /* Copy initial value of state bits into 'old' bit-wise */
+    bitmap_set_value(old, 64, state[0], width[0], 0);
+    bitmap_set_value(old, 64, state[1], width[1], width[0]);
+    /* Copy value from 'old' into 'new' with mask applied */
+    bitmap_replace(new, old, bits, mask, gc->ngpio);
+
+    bitmap_from_arr32(old, state, 64);
+    /* Update 'state' */
+    state[0] = bitmap_get_value(new, 0, width[0]);
+    state[1] = bitmap_get_value(new, width[0], width[1]);
+    bitmap_from_arr32(new, state, 64);
+    /* XOR operation sets only changed bits */
+    bitmap_xor(changed, old, new, 64);
+
+    if (((u32 *)changed)[0])
+        xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET, state[0]);
+    if (((u32 *)changed)[1])
+        xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
+                XGPIO_CHANNEL_OFFSET, state[1]);
+
+    spin_unlock_irqrestore(&chip->gpio_lock, flags);
 }
 
 /**