[v3,3/3] gpio: xilinx: Utilize generic bitmap_get_value and _set_value

Commit Message

Syed Nayyar Waris March 6, 2021, 2:06 p.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 <[e-mail]>
Cc: Michal Simek <[e-mail]>
Signed-off-by: Syed Nayyar Waris <[e-mail]>
Acked-by: William Breathitt Gray <[e-mail]>
---
 drivers/gpio/gpio-xilinx.c | 63 +++++++++++++++++++-------------------
 1 file changed, 32 insertions(+), 31 deletions(-)

Comments

Michal Simek March 8, 2021, 7:13 a.m. UTC | #1

On 3/6/21 3:06 PM, Syed Nayyar Waris 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 <[e-mail]>
> Cc: Michal Simek <[e-mail]>
> Signed-off-by: Syed Nayyar Waris <[e-mail]>
> Acked-by: William Breathitt Gray <[e-mail]>
> ---
>  drivers/gpio/gpio-xilinx.c | 63 +++++++++++++++++++-------------------
>  1 file changed, 32 insertions(+), 31 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> index be539381fd82..8445e69cf37b 100644
> --- a/drivers/gpio/gpio-xilinx.c
> +++ b/drivers/gpio/gpio-xilinx.c
> @@ -15,6 +15,7 @@
>  #include <linux/of_device.h>
>  #include <linux/of_platform.h>
>  #include <linux/slab.h>
> +#include "gpiolib.h"
>  
>  /* Register Offset Definitions */
>  #define XGPIO_DATA_OFFSET   (0x0)	/* Data register  */
> @@ -141,37 +142,37 @@ 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[index], 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[index], flags);
> -			index =  xgpio_index(chip, i);
> -			spin_lock_irqsave(&chip->gpio_lock[index], 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[index], flags);
> +	u32 *const state = chip->gpio_state;
> +	unsigned int *const width = chip->gpio_width;
> +
> +	DECLARE_BITMAP(old, 64);
> +	DECLARE_BITMAP(new, 64);
> +	DECLARE_BITMAP(changed, 64);
> +
> +	spin_lock_irqsave(&chip->gpio_lock[0], flags);
> +	spin_lock(&chip->gpio_lock[1]);
> +
> +	bitmap_set_value(old, 64, state[0], width[0], 0);
> +	bitmap_set_value(old, 64, state[1], width[1], width[0]);
> +	bitmap_replace(new, old, bits, mask, gc->ngpio);
> +
> +	bitmap_set_value(old, 64, state[0], 32, 0);
> +	bitmap_set_value(old, 64, state[1], 32, 32);
> +	state[0] = bitmap_get_value(new, 0, width[0]);
> +	state[1] = bitmap_get_value(new, width[0], width[1]);
> +	bitmap_set_value(new, 64, state[0], 32, 0);
> +	bitmap_set_value(new, 64, state[1], 32, 32);
> +	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(&chip->gpio_lock[1]);
> +	spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
>  }
>  
>  /**
> 

Srinivas N: Can you please test this code?

Thanks,
Michal

Bartosz Golaszewski March 26, 2021, 5:27 p.m. UTC | #2

On Mon, Mar 8, 2021 at 8:13 AM Michal Simek <[e-mail]> wrote:
>
>
>
> On 3/6/21 3:06 PM, Syed Nayyar Waris 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 <[e-mail]>
> > Cc: Michal Simek <[e-mail]>
> > Signed-off-by: Syed Nayyar Waris <[e-mail]>
> > Acked-by: William Breathitt Gray <[e-mail]>
> > ---
> >  drivers/gpio/gpio-xilinx.c | 63 +++++++++++++++++++-------------------
> >  1 file changed, 32 insertions(+), 31 deletions(-)
> >
> > diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> > index be539381fd82..8445e69cf37b 100644
> > --- a/drivers/gpio/gpio-xilinx.c
> > +++ b/drivers/gpio/gpio-xilinx.c
> > @@ -15,6 +15,7 @@
> >  #include <linux/of_device.h>
> >  #include <linux/of_platform.h>
> >  #include <linux/slab.h>
> > +#include "gpiolib.h"
> >
> >  /* Register Offset Definitions */
> >  #define XGPIO_DATA_OFFSET   (0x0)    /* Data register  */
> > @@ -141,37 +142,37 @@ 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[index], 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[index], flags);
> > -                     index =  xgpio_index(chip, i);
> > -                     spin_lock_irqsave(&chip->gpio_lock[index], 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[index], flags);
> > +     u32 *const state = chip->gpio_state;
> > +     unsigned int *const width = chip->gpio_width;
> > +
> > +     DECLARE_BITMAP(old, 64);
> > +     DECLARE_BITMAP(new, 64);
> > +     DECLARE_BITMAP(changed, 64);
> > +
> > +     spin_lock_irqsave(&chip->gpio_lock[0], flags);
> > +     spin_lock(&chip->gpio_lock[1]);
> > +
> > +     bitmap_set_value(old, 64, state[0], width[0], 0);
> > +     bitmap_set_value(old, 64, state[1], width[1], width[0]);
> > +     bitmap_replace(new, old, bits, mask, gc->ngpio);
> > +
> > +     bitmap_set_value(old, 64, state[0], 32, 0);
> > +     bitmap_set_value(old, 64, state[1], 32, 32);
> > +     state[0] = bitmap_get_value(new, 0, width[0]);
> > +     state[1] = bitmap_get_value(new, width[0], width[1]);
> > +     bitmap_set_value(new, 64, state[0], 32, 0);
> > +     bitmap_set_value(new, 64, state[1], 32, 32);
> > +     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(&chip->gpio_lock[1]);
> > +     spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
> >  }
> >
> >  /**
> >
>
> Srinivas N: Can you please test this code?
>
> Thanks,
> Michal

Hey, any chance of getting that Tested-by?

Bart

Andy Shevchenko March 26, 2021, 5:57 p.m. UTC | #3

On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <[e-mail]> 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.

...

> +       u32 *const state = chip->gpio_state;
> +       unsigned int *const width = chip->gpio_width;

> +

Extra blank line.

> +       DECLARE_BITMAP(old, 64);
> +       DECLARE_BITMAP(new, 64);
> +       DECLARE_BITMAP(changed, 64);

> +       spin_lock_irqsave(&chip->gpio_lock[0], flags);
> +       spin_lock(&chip->gpio_lock[1]);

I understand why this is done at the top of the function in the original code.
I do not understand why you put some operations under spin lock.

Have you checked what each of these spin locks protects?
Please check and try to lock as minimum as possible.

> +       bitmap_set_value(old, 64, state[0], width[0], 0);
> +       bitmap_set_value(old, 64, state[1], width[1], width[0]);
> +       bitmap_replace(new, old, bits, mask, gc->ngpio);
> +
> +       bitmap_set_value(old, 64, state[0], 32, 0);
> +       bitmap_set_value(old, 64, state[1], 32, 32);
> +       state[0] = bitmap_get_value(new, 0, width[0]);
> +       state[1] = bitmap_get_value(new, width[0], width[1]);
> +       bitmap_set_value(new, 64, state[0], 32, 0);
> +       bitmap_set_value(new, 64, state[1], 32, 32);
> +       bitmap_xor(changed, old, new, 64);

Original code and this is cryptic. Can you add a few comments
explaining what is going on here?

> +       spin_unlock(&chip->gpio_lock[1]);
> +       spin_unlock_irqrestore(&chip->gpio_lock[0], flags);

Andy Shevchenko March 26, 2021, 6:02 p.m. UTC | #4

On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <[e-mail]> wrote:

> +       bitmap_set_value(old, 64, state[0], 32, 0);
> +       bitmap_set_value(old, 64, state[1], 32, 32);

Isn't it effectively bitnap_from_arr32() ?

> +       bitmap_set_value(new, 64, state[0], 32, 0);
> +       bitmap_set_value(new, 64, state[1], 32, 32);

Ditto.

Syed Nayyar Waris March 26, 2021, 10:12 p.m. UTC | #5

On Fri, Mar 26, 2021 at 11:32 PM Andy Shevchenko
<[e-mail]> wrote:
>
> On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <[e-mail]> wrote:
>
> > +       bitmap_set_value(old, 64, state[0], 32, 0);
> > +       bitmap_set_value(old, 64, state[1], 32, 32);
>
> Isn't it effectively bitnap_from_arr32() ?
>
> > +       bitmap_set_value(new, 64, state[0], 32, 0);
> > +       bitmap_set_value(new, 64, state[1], 32, 32);
>
> Ditto.
>
> --
> With Best Regards,
> Andy Shevchenko

Hi Andy,

With bitmap_set_value() we are also specifying the offset (or start)
position too. so that the remainder of the array remains unaffected. I
think it would not be feasible to use bitmap_from/to_arr32()  here.

Regards
Syed Nayyar Waris

William Breathitt Gray March 27, 2021, 12:02 p.m. UTC | #6

On Sat, Mar 27, 2021 at 09:29:26AM +0200, Andy Shevchenko wrote:
> On Saturday, March 27, 2021, Syed Nayyar Waris <[e-mail]> wrote:
> 
> > On Fri, Mar 26, 2021 at 11:32 PM Andy Shevchenko
> > <[e-mail]> wrote:
> > >
> > > On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <[e-mail]>
> > wrote:
> > >
> > > > +       bitmap_set_value(old, 64, state[0], 32, 0);
> > > > +       bitmap_set_value(old, 64, state[1], 32, 32);
> > >
> > > Isn't it effectively bitnap_from_arr32() ?
> > >
> > > > +       bitmap_set_value(new, 64, state[0], 32, 0);
> > > > +       bitmap_set_value(new, 64, state[1], 32, 32);
> > >
> > > Ditto.
> > >
> > > --
> > > With Best Regards,
> > > Andy Shevchenko
> >
> > Hi Andy,
> >
> > With bitmap_set_value() we are also specifying the offset (or start)
> > position too. so that the remainder of the array remains unaffected. I
> > think it would not be feasible to use bitmap_from/to_arr32()  here.
> 
> 
> You have hard coded start and nbits parameters to 32. How is it not the
> same?

Would these four lines become something like this:

	bitmap_from_arr32(old, state, 64);
	...
	bitmap_from_arr32(new, state, 64);

Sincerely,

William Breathitt Gray

Andy Shevchenko March 27, 2021, 4:35 p.m. UTC | #7

On Sat, Mar 27, 2021 at 2:02 PM William Breathitt Gray
<[e-mail]> wrote:
> On Sat, Mar 27, 2021 at 09:29:26AM +0200, Andy Shevchenko wrote:
> > On Saturday, March 27, 2021, Syed Nayyar Waris <[e-mail]> wrote:
> > > On Fri, Mar 26, 2021 at 11:32 PM Andy Shevchenko
> > > <[e-mail]> wrote:
> > > > On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <[e-mail]>
> > > wrote:
> > > >
> > > > > +       bitmap_set_value(old, 64, state[0], 32, 0);
> > > > > +       bitmap_set_value(old, 64, state[1], 32, 32);
> > > >
> > > > Isn't it effectively bitnap_from_arr32() ?
> > > >
> > > > > +       bitmap_set_value(new, 64, state[0], 32, 0);
> > > > > +       bitmap_set_value(new, 64, state[1], 32, 32);
> > > >
> > > > Ditto.

> > > With bitmap_set_value() we are also specifying the offset (or start)
> > > position too. so that the remainder of the array remains unaffected. I
> > > think it would not be feasible to use bitmap_from/to_arr32()  here.
> >
> >
> > You have hard coded start and nbits parameters to 32. How is it not the
> > same?
>
> Would these four lines become something like this:
>
>         bitmap_from_arr32(old, state, 64);
>         ...
>         bitmap_from_arr32(new, state, 64);

This is my understanding, but I might miss something. I mean driver
specifics that make my proposal incorrect.

Andy Shevchenko March 29, 2021, 3:24 p.m. UTC | #8

On Sat, Mar 06, 2021 at 07:36:30PM +0530, Syed Nayyar Waris 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.

...

> +	u32 *const state = chip->gpio_state;

Looking at this... What's the point of the const here?

Am I right that this tells: pointer is a const, while the data underneath
can be modified?

> +	unsigned int *const width = chip->gpio_width;

Ditto.

Putting const:s here and there for sake of the const is not good practice.
It makes code harder to read.

Srinivas Neeli March 31, 2021, 3:26 p.m. UTC | #9

Hi,

> -----Original Message-----
> From: Bartosz Golaszewski <[e-mail]>
> Sent: Friday, March 26, 2021 10:58 PM
> To: Michal Simek <[e-mail]>
> Cc: Syed Nayyar Waris <[e-mail]>; Srinivas Neeli
> <[e-mail]>; Andy Shevchenko
> <[e-mail]>; William Breathitt Gray
> <[e-mail]>; Arnd Bergmann <[e-mail]>; Robert
> Richter <[e-mail]>; Linus Walleij <[e-mail]>;
> Masahiro Yamada <[e-mail]>; Andrew Morton
> <[e-mail]>; Zhang Rui <[e-mail]>; Daniel
> Lezcano <[e-mail]>; Amit Kucheria
> <[e-mail]>; Linux-Arch <[e-mail]>;
> linux-gpio <[e-mail]>; LKML <linux-
> [e-mail]>; arm-soc <[e-mail]>;
> linux-pm <[e-mail]>; Srinivas Goud <[e-mail]>
> Subject: Re: [PATCH v3 3/3] gpio: xilinx: Utilize generic bitmap_get_value and
> _set_value
> 
> On Mon, Mar 8, 2021 at 8:13 AM Michal Simek <[e-mail]>
> wrote:
> >
> >
> >
> > On 3/6/21 3:06 PM, Syed Nayyar Waris 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 <[e-mail]>
> > > Cc: Michal Simek <[e-mail]>
> > > Signed-off-by: Syed Nayyar Waris <[e-mail]>
> > > Acked-by: William Breathitt Gray <[e-mail]>
> > > ---
> > >  drivers/gpio/gpio-xilinx.c | 63
> > > +++++++++++++++++++-------------------
> > >  1 file changed, 32 insertions(+), 31 deletions(-)
> > >
> > > diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> > > index be539381fd82..8445e69cf37b 100644
> > > --- a/drivers/gpio/gpio-xilinx.c
> > > +++ b/drivers/gpio/gpio-xilinx.c
> > > @@ -15,6 +15,7 @@
> > >  #include <linux/of_device.h>
> > >  #include <linux/of_platform.h>
> > >  #include <linux/slab.h>
> > > +#include "gpiolib.h"
> > >
> > >  /* Register Offset Definitions */
> > >  #define XGPIO_DATA_OFFSET   (0x0)    /* Data register  */
> > > @@ -141,37 +142,37 @@ 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[index], 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[index], flags);
> > > -                     index =  xgpio_index(chip, i);
> > > -                     spin_lock_irqsave(&chip->gpio_lock[index], 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[index], flags);
> > > +     u32 *const state = chip->gpio_state;
> > > +     unsigned int *const width = chip->gpio_width;
> > > +
> > > +     DECLARE_BITMAP(old, 64);
> > > +     DECLARE_BITMAP(new, 64);
> > > +     DECLARE_BITMAP(changed, 64);
> > > +
> > > +     spin_lock_irqsave(&chip->gpio_lock[0], flags);
> > > +     spin_lock(&chip->gpio_lock[1]);
> > > +
> > > +     bitmap_set_value(old, 64, state[0], width[0], 0);
> > > +     bitmap_set_value(old, 64, state[1], width[1], width[0]);
> > > +     bitmap_replace(new, old, bits, mask, gc->ngpio);
> > > +
> > > +     bitmap_set_value(old, 64, state[0], 32, 0);
> > > +     bitmap_set_value(old, 64, state[1], 32, 32);
> > > +     state[0] = bitmap_get_value(new, 0, width[0]);
> > > +     state[1] = bitmap_get_value(new, width[0], width[1]);
> > > +     bitmap_set_value(new, 64, state[0], 32, 0);
> > > +     bitmap_set_value(new, 64, state[1], 32, 32);
> > > +     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(&chip->gpio_lock[1]);
> > > +     spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
> > >  }
> > >
> > >  /**
> > >
> >
> > Srinivas N: Can you please test this code?
> >
> > Thanks,
> > Michal
> 
> Hey, any chance of getting that Tested-by?
I tested patches with few modifications in code (spin_lock handling and merge conflict).
functionality wise it's working fine.

> 
> Bart

Syed Nayyar Waris April 1, 2021, 11:15 a.m. UTC | #10

On Wed, Mar 31, 2021 at 8:56 PM Srinivas Neeli <[e-mail]> wrote:
>
> Hi,
>
> > -----Original Message-----
> > From: Bartosz Golaszewski <[e-mail]>
> > Sent: Friday, March 26, 2021 10:58 PM
> > To: Michal Simek <[e-mail]>
> > Cc: Syed Nayyar Waris <[e-mail]>; Srinivas Neeli
> > <[e-mail]>; Andy Shevchenko
> > <[e-mail]>; William Breathitt Gray
> > <[e-mail]>; Arnd Bergmann <[e-mail]>; Robert
> > Richter <[e-mail]>; Linus Walleij <[e-mail]>;
> > Masahiro Yamada <[e-mail]>; Andrew Morton
> > <[e-mail]>; Zhang Rui <[e-mail]>; Daniel
> > Lezcano <[e-mail]>; Amit Kucheria
> > <[e-mail]>; Linux-Arch <[e-mail]>;
> > linux-gpio <[e-mail]>; LKML <linux-
> > [e-mail]>; arm-soc <[e-mail]>;
> > linux-pm <[e-mail]>; Srinivas Goud <[e-mail]>
> > Subject: Re: [PATCH v3 3/3] gpio: xilinx: Utilize generic bitmap_get_value and
> > _set_value
> >
> > On Mon, Mar 8, 2021 at 8:13 AM Michal Simek <[e-mail]>
> > wrote:
> > >
> > >
> > >
> > > On 3/6/21 3:06 PM, Syed Nayyar Waris 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 <[e-mail]>
> > > > Cc: Michal Simek <[e-mail]>
> > > > Signed-off-by: Syed Nayyar Waris <[e-mail]>
> > > > Acked-by: William Breathitt Gray <[e-mail]>
> > > > ---
> > > >  drivers/gpio/gpio-xilinx.c | 63
> > > > +++++++++++++++++++-------------------
> > > >  1 file changed, 32 insertions(+), 31 deletions(-)
> > > >
> > > > diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> > > > index be539381fd82..8445e69cf37b 100644
> > > > --- a/drivers/gpio/gpio-xilinx.c
> > > > +++ b/drivers/gpio/gpio-xilinx.c
> > > > @@ -15,6 +15,7 @@
> > > >  #include <linux/of_device.h>
> > > >  #include <linux/of_platform.h>
> > > >  #include <linux/slab.h>
> > > > +#include "gpiolib.h"
> > > >
> > > >  /* Register Offset Definitions */
> > > >  #define XGPIO_DATA_OFFSET   (0x0)    /* Data register  */
> > > > @@ -141,37 +142,37 @@ 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[index], 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[index], flags);
> > > > -                     index =  xgpio_index(chip, i);
> > > > -                     spin_lock_irqsave(&chip->gpio_lock[index], 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[index], flags);
> > > > +     u32 *const state = chip->gpio_state;
> > > > +     unsigned int *const width = chip->gpio_width;
> > > > +
> > > > +     DECLARE_BITMAP(old, 64);
> > > > +     DECLARE_BITMAP(new, 64);
> > > > +     DECLARE_BITMAP(changed, 64);
> > > > +
> > > > +     spin_lock_irqsave(&chip->gpio_lock[0], flags);
> > > > +     spin_lock(&chip->gpio_lock[1]);
> > > > +
> > > > +     bitmap_set_value(old, 64, state[0], width[0], 0);
> > > > +     bitmap_set_value(old, 64, state[1], width[1], width[0]);
> > > > +     bitmap_replace(new, old, bits, mask, gc->ngpio);
> > > > +
> > > > +     bitmap_set_value(old, 64, state[0], 32, 0);
> > > > +     bitmap_set_value(old, 64, state[1], 32, 32);
> > > > +     state[0] = bitmap_get_value(new, 0, width[0]);
> > > > +     state[1] = bitmap_get_value(new, width[0], width[1]);
> > > > +     bitmap_set_value(new, 64, state[0], 32, 0);
> > > > +     bitmap_set_value(new, 64, state[1], 32, 32);
> > > > +     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(&chip->gpio_lock[1]);
> > > > +     spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
> > > >  }
> > > >
> > > >  /**
> > > >
> > >
> > > Srinivas N: Can you please test this code?
> > >
> > > Thanks,
> > > Michal
> >
> > Hey, any chance of getting that Tested-by?
> I tested patches with few modifications in code (spin_lock handling and merge conflict).
> functionality wise it's working fine.
>
> >
> > Bart

Hi Bartosz,

May I please know the URL of the tree that you are using. I had been
using the tree below for submitting this patchset on GPIO to you.
https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git

I think I am using the wrong tree. On which tree should I base my
patches on for my next  (v4) submission? Should I use the tree below?
:
https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git

Regards
Syed Nayyar Waris

Bartosz Golaszewski April 1, 2021, 12:51 p.m. UTC | #11

On Thu, Apr 1, 2021 at 1:16 PM Syed Nayyar Waris <[e-mail]> wrote:
>
> On Wed, Mar 31, 2021 at 8:56 PM Srinivas Neeli <[e-mail]> wrote:
> >
> > Hi,
> >
> > > -----Original Message-----
> > > From: Bartosz Golaszewski <[e-mail]>
> > > Sent: Friday, March 26, 2021 10:58 PM
> > > To: Michal Simek <[e-mail]>
> > > Cc: Syed Nayyar Waris <[e-mail]>; Srinivas Neeli
> > > <[e-mail]>; Andy Shevchenko
> > > <[e-mail]>; William Breathitt Gray
> > > <[e-mail]>; Arnd Bergmann <[e-mail]>; Robert
> > > Richter <[e-mail]>; Linus Walleij <[e-mail]>;
> > > Masahiro Yamada <[e-mail]>; Andrew Morton
> > > <[e-mail]>; Zhang Rui <[e-mail]>; Daniel
> > > Lezcano <[e-mail]>; Amit Kucheria
> > > <[e-mail]>; Linux-Arch <[e-mail]>;
> > > linux-gpio <[e-mail]>; LKML <linux-
> > > [e-mail]>; arm-soc <[e-mail]>;
> > > linux-pm <[e-mail]>; Srinivas Goud <[e-mail]>
> > > Subject: Re: [PATCH v3 3/3] gpio: xilinx: Utilize generic bitmap_get_value and
> > > _set_value
> > >
> > > On Mon, Mar 8, 2021 at 8:13 AM Michal Simek <[e-mail]>
> > > wrote:
> > > >
> > > >
> > > >
> > > > On 3/6/21 3:06 PM, Syed Nayyar Waris 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 <[e-mail]>
> > > > > Cc: Michal Simek <[e-mail]>
> > > > > Signed-off-by: Syed Nayyar Waris <[e-mail]>
> > > > > Acked-by: William Breathitt Gray <[e-mail]>
> > > > > ---
> > > > >  drivers/gpio/gpio-xilinx.c | 63
> > > > > +++++++++++++++++++-------------------
> > > > >  1 file changed, 32 insertions(+), 31 deletions(-)
> > > > >
> > > > > diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> > > > > index be539381fd82..8445e69cf37b 100644
> > > > > --- a/drivers/gpio/gpio-xilinx.c
> > > > > +++ b/drivers/gpio/gpio-xilinx.c
> > > > > @@ -15,6 +15,7 @@
> > > > >  #include <linux/of_device.h>
> > > > >  #include <linux/of_platform.h>
> > > > >  #include <linux/slab.h>
> > > > > +#include "gpiolib.h"
> > > > >
> > > > >  /* Register Offset Definitions */
> > > > >  #define XGPIO_DATA_OFFSET   (0x0)    /* Data register  */
> > > > > @@ -141,37 +142,37 @@ 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[index], 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[index], flags);
> > > > > -                     index =  xgpio_index(chip, i);
> > > > > -                     spin_lock_irqsave(&chip->gpio_lock[index], 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[index], flags);
> > > > > +     u32 *const state = chip->gpio_state;
> > > > > +     unsigned int *const width = chip->gpio_width;
> > > > > +
> > > > > +     DECLARE_BITMAP(old, 64);
> > > > > +     DECLARE_BITMAP(new, 64);
> > > > > +     DECLARE_BITMAP(changed, 64);
> > > > > +
> > > > > +     spin_lock_irqsave(&chip->gpio_lock[0], flags);
> > > > > +     spin_lock(&chip->gpio_lock[1]);
> > > > > +
> > > > > +     bitmap_set_value(old, 64, state[0], width[0], 0);
> > > > > +     bitmap_set_value(old, 64, state[1], width[1], width[0]);
> > > > > +     bitmap_replace(new, old, bits, mask, gc->ngpio);
> > > > > +
> > > > > +     bitmap_set_value(old, 64, state[0], 32, 0);
> > > > > +     bitmap_set_value(old, 64, state[1], 32, 32);
> > > > > +     state[0] = bitmap_get_value(new, 0, width[0]);
> > > > > +     state[1] = bitmap_get_value(new, width[0], width[1]);
> > > > > +     bitmap_set_value(new, 64, state[0], 32, 0);
> > > > > +     bitmap_set_value(new, 64, state[1], 32, 32);
> > > > > +     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(&chip->gpio_lock[1]);
> > > > > +     spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
> > > > >  }
> > > > >
> > > > >  /**
> > > > >
> > > >
> > > > Srinivas N: Can you please test this code?
> > > >
> > > > Thanks,
> > > > Michal
> > >
> > > Hey, any chance of getting that Tested-by?
> > I tested patches with few modifications in code (spin_lock handling and merge conflict).
> > functionality wise it's working fine.
> >
> > >
> > > Bart
>
> Hi Bartosz,
>
> May I please know the URL of the tree that you are using. I had been
> using the tree below for submitting this patchset on GPIO to you.
> https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git
>
> I think I am using the wrong tree. On which tree should I base my
> patches on for my next  (v4) submission? Should I use the tree below?
> :
> https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git
>
> Regards
> Syed Nayyar Waris

Yes this is the one. Please address new issues raised by reviewers.

Bart

Syed Nayyar Waris April 1, 2021, 5:47 p.m. UTC | #12

On Mon, Mar 29, 2021 at 8:54 PM Andy Shevchenko
<[e-mail]> wrote:
>
> On Sat, Mar 06, 2021 at 07:36:30PM +0530, Syed Nayyar Waris 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.
>
> ...
>
> > +     u32 *const state = chip->gpio_state;
>
> Looking at this... What's the point of the const here?
>
> Am I right that this tells: pointer is a const, while the data underneath
> can be modified?
>
> > +     unsigned int *const width = chip->gpio_width;
>
> Ditto.
>
> Putting const:s here and there for sake of the const is not good practice.
> It makes code harder to read.
>
> --
> With Best Regards,
> Andy Shevchenko
>
Okay. I will incorporate your comments in my next submission. Thank You.

Regards
Syed Nayyar Waris

Syed Nayyar Waris April 1, 2021, 5:50 p.m. UTC | #13

On Sat, Mar 27, 2021 at 10:05 PM Andy Shevchenko
<[e-mail]> wrote:
>
> On Sat, Mar 27, 2021 at 2:02 PM William Breathitt Gray
> <[e-mail]> wrote:
> > On Sat, Mar 27, 2021 at 09:29:26AM +0200, Andy Shevchenko wrote:
> > > On Saturday, March 27, 2021, Syed Nayyar Waris <[e-mail]> wrote:
> > > > On Fri, Mar 26, 2021 at 11:32 PM Andy Shevchenko
> > > > <[e-mail]> wrote:
> > > > > On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <[e-mail]>
> > > > wrote:
> > > > >
> > > > > > +       bitmap_set_value(old, 64, state[0], 32, 0);
> > > > > > +       bitmap_set_value(old, 64, state[1], 32, 32);
> > > > >
> > > > > Isn't it effectively bitnap_from_arr32() ?
> > > > >
> > > > > > +       bitmap_set_value(new, 64, state[0], 32, 0);
> > > > > > +       bitmap_set_value(new, 64, state[1], 32, 32);
> > > > >
> > > > > Ditto.
>
> > > > With bitmap_set_value() we are also specifying the offset (or start)
> > > > position too. so that the remainder of the array remains unaffected. I
> > > > think it would not be feasible to use bitmap_from/to_arr32()  here.
> > >
> > >
> > > You have hard coded start and nbits parameters to 32. How is it not the
> > > same?
> >
> > Would these four lines become something like this:
> >
> >         bitmap_from_arr32(old, state, 64);
> >         ...
> >         bitmap_from_arr32(new, state, 64);
>
> This is my understanding, but I might miss something. I mean driver
> specifics that make my proposal incorrect.
>
> --
> With Best Regards,
> Andy Shevchenko

I initially (incorrectly) thought that all of the bitmap_set_value()
statements have to be replaced. But now I realised, only those
specific bitmap_set_value() calls containing 32 bits width have to
replaced.

I will incorporate the above review comments in my next v4 submission.

Regards
Syed Nayyar Waris

Syed Nayyar Waris April 2, 2021, 9:40 a.m. UTC | #14

On Fri, Mar 26, 2021 at 11:27 PM Andy Shevchenko
<[e-mail]> wrote:
>
> On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <[e-mail]> 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.
>
> ...
>
> > +       u32 *const state = chip->gpio_state;
> > +       unsigned int *const width = chip->gpio_width;
>
> > +
>
> Extra blank line.
>
> > +       DECLARE_BITMAP(old, 64);
> > +       DECLARE_BITMAP(new, 64);
> > +       DECLARE_BITMAP(changed, 64);
>
> > +       spin_lock_irqsave(&chip->gpio_lock[0], flags);
> > +       spin_lock(&chip->gpio_lock[1]);
>
> I understand why this is done at the top of the function in the original code.
> I do not understand why you put some operations under spin lock.
>
> Have you checked what each of these spin locks protects?
> Please check and try to lock as minimum as possible.
>
> > +       bitmap_set_value(old, 64, state[0], width[0], 0);
> > +       bitmap_set_value(old, 64, state[1], width[1], width[0]);
> > +       bitmap_replace(new, old, bits, mask, gc->ngpio);
> > +
> > +       bitmap_set_value(old, 64, state[0], 32, 0);
> > +       bitmap_set_value(old, 64, state[1], 32, 32);
> > +       state[0] = bitmap_get_value(new, 0, width[0]);
> > +       state[1] = bitmap_get_value(new, width[0], width[1]);
> > +       bitmap_set_value(new, 64, state[0], 32, 0);
> > +       bitmap_set_value(new, 64, state[1], 32, 32);
> > +       bitmap_xor(changed, old, new, 64);
>
> Original code and this is cryptic. Can you add a few comments
> explaining what is going on here?
>
> > +       spin_unlock(&chip->gpio_lock[1]);
> > +       spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
>
> --
> With Best Regards,
> Andy Shevchenko

Have removed the extra line and added comments. Regarding locking - I
see that now there is just a single lock available instead of 2 locks.
Have made necessary changes. Thanks
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/gpio/gpio-xilinx.c?id=37ef334680800263b32bb96a5156a4b47f0244a2

Regards

Syed Nayyar Waris

Syed Nayyar Waris April 2, 2021, 10:07 a.m. UTC | #15

On Mon, Mar 29, 2021 at 8:54 PM Andy Shevchenko
<[e-mail]> wrote:
>
> On Sat, Mar 06, 2021 at 07:36:30PM +0530, Syed Nayyar Waris 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.
>
> ...
>
> > +     u32 *const state = chip->gpio_state;
>
> Looking at this... What's the point of the const here?
>
> Am I right that this tells: pointer is a const, while the data underneath
> can be modified?

Yes you are right and the data underneath can be modified.
I have removed the 'const' in v4

>
> > +     unsigned int *const width = chip->gpio_width;
>
> Ditto.
>
> Putting const:s here and there for sake of the const is not good practice.
> It makes code harder to read.

Okay.

>
> --
> With Best Regards,
> Andy Shevchenko
>
>

Patch

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index be539381fd82..8445e69cf37b 100644
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -15,6 +15,7 @@ 
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
 #include <linux/slab.h>
+#include "gpiolib.h"
 
 /* Register Offset Definitions */
 #define XGPIO_DATA_OFFSET   (0x0)	/* Data register  */
@@ -141,37 +142,37 @@  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[index], 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[index], flags);
-			index =  xgpio_index(chip, i);
-			spin_lock_irqsave(&chip->gpio_lock[index], 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[index], flags);
+	u32 *const state = chip->gpio_state;
+	unsigned int *const width = chip->gpio_width;
+
+	DECLARE_BITMAP(old, 64);
+	DECLARE_BITMAP(new, 64);
+	DECLARE_BITMAP(changed, 64);
+
+	spin_lock_irqsave(&chip->gpio_lock[0], flags);
+	spin_lock(&chip->gpio_lock[1]);
+
+	bitmap_set_value(old, 64, state[0], width[0], 0);
+	bitmap_set_value(old, 64, state[1], width[1], width[0]);
+	bitmap_replace(new, old, bits, mask, gc->ngpio);
+
+	bitmap_set_value(old, 64, state[0], 32, 0);
+	bitmap_set_value(old, 64, state[1], 32, 32);
+	state[0] = bitmap_get_value(new, 0, width[0]);
+	state[1] = bitmap_get_value(new, width[0], width[1]);
+	bitmap_set_value(new, 64, state[0], 32, 0);
+	bitmap_set_value(new, 64, state[1], 32, 32);
+	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(&chip->gpio_lock[1]);
+	spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
 }
 
 /**