Re: [PATCH] regulator: pfuze100: Simplify pfuze100_set_ramp_delayimplementation

From: Robin Gong
Date: Wed Jul 31 2013 - 11:42:58 EST


>From software view this patch looks better, although original code match better
with the data sheet. Thanks Axel.

Reviewed-by: Robin Gong <b38343@xxxxxxxxxxxxx>
Thanks.
On Tue, Jul 30, 2013 at 10:47:44PM +0800, Axel Lin wrote:
> Simplify the equation to calculate ramp_delay.
> Below equations are equivalent:
> ramp_delay = 25000 / (2 * ramp_delay);
> ramp_delay = 50000 / (4 * ramp_delay);
> ramp_delay = 25000 / (2 * ramp_delay);
> ramp_delay = 12500 / ramp_delay;
> So we don't need to read BIT6 of rdev->desc->vsel_reg for applying different
> equations.
>
> Also use rdev->desc->vsel_reg instead of run-time calculate register address.
>
> Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
> ---
> drivers/regulator/pfuze100-regulator.c | 21 +++++----------------
> 1 file changed, 5 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/regulator/pfuze100-regulator.c b/drivers/regulator/pfuze100-regulator.c
> index e02d9b9..bda5561 100644
> --- a/drivers/regulator/pfuze100-regulator.c
> +++ b/drivers/regulator/pfuze100-regulator.c
> @@ -93,26 +93,15 @@ static int pfuze100_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
> {
> struct pfuze_chip *pfuze100 = rdev_get_drvdata(rdev);
> int id = rdev->desc->id;
> - unsigned int val, ramp_bits, reg;
> + unsigned int ramp_bits;
> int ret;
>
> if (id < PFUZE100_SWBST) {
> - if (id == PFUZE100_SW1AB)
> - reg = PFUZE100_SW1ABVOL;
> - else
> - reg = PFUZE100_SW1CVOL + (id - PFUZE100_SW1C) * 7;
> - regmap_read(pfuze100->regmap, reg, &val);
> -
> - if (id <= PFUZE100_SW1C)
> - ramp_delay = 25000 / (2 * ramp_delay);
> - else if (val & 0x40)
> - ramp_delay = 50000 / (4 * ramp_delay);
> - else
> - ramp_delay = 25000 / (2 * ramp_delay);
> -
> + ramp_delay = 12500 / ramp_delay;
> ramp_bits = (ramp_delay >> 1) - (ramp_delay >> 3);
> - ret = regmap_update_bits(pfuze100->regmap, reg + 4 , 0xc0,
> - ramp_bits << 6);
> + ret = regmap_update_bits(pfuze100->regmap,
> + rdev->desc->vsel_reg + 4,
> + 0xc0, ramp_bits << 6);
> if (ret < 0)
> dev_err(pfuze100->dev, "ramp failed, err %d\n", ret);
> } else
> --
> 1.8.1.2
>
>
>
>

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