Re: [PATCH 3/3] Replace for_each_*_bit_from() with for_each_*_bit() where appropriate

On Sat, Jun 19, 2021 at 01:49:58PM +0300, Andy Shevchenko wrote:

On Fri, Jun 18, 2021 at 12:57:35PM -0700, Yury Norov wrote:

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A couple of kernel functions call for_each_*_bit_from() with start bit equal to 0. Replace them with for_each_*_bit().

No functional changes, but might improve on readability.

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--- a/drivers/hwmon/ltc2992.c +++ b/drivers/hwmon/ltc2992.c @@ -248,8 +248,7 @@ static int ltc2992_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask

gpio_status = reg;

• gpio_nr = 0;
• for_each_set_bit_from(gpio_nr, mask, LTC2992_GPIO_NR) {

• for_each_set_bit(gpio_nr, mask, LTC2992_GPIO_NR) { if (test_bit(LTC2992_GPIO_BIT(gpio_nr), &gpio_status)) set_bit(gpio_nr, bits); }

I would replace the entire loop by bitmap_replace() call.

Something like bitmap_replace(bits, bits, &gpio_status, mask, LTC2992_GPIO_NR);

Okay, it wouldn't work directly because it involves LTC2992_GPIO_BIT() macro. So, it rather some kind of bitmap_remap().