Re: [PATCH RFT] regulator: palmas: Fix calcuating selector in palmas_map_voltage_smps

From: Graeme Gregory
Date: Tue Jul 17 2012 - 04:45:56 EST


Good catch, thanks I totally forgot about the range bit in that function.

Acked-by: Graeme Gregory <gg@xxxxxxxxxxxxxxx>

On 17/07/12 04:29, Axel Lin wrote:
> The logic of calculating selector in palmas_map_voltage_smps() does not match
> the logic to list voltage in palmas_list_voltage_smps().
>
> We use below equation to calculate voltage when selector > 0:
> voltage = (0.49V + (selector * 0.01V)) * RANGE
> RANGE is either x1 or x2
>
> So we need to take into account with the multiplier set in VSEL register when
> calculating selector in palmas_map_voltage_smps()
>
> Signed-off-by: Axel Lin <axel.lin@xxxxxxxxx>
> ---
> drivers/regulator/palmas-regulator.c | 17 ++++++++++++++---
> 1 file changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/regulator/palmas-regulator.c b/drivers/regulator/palmas-regulator.c
> index 7540c95..17d19fb 100644
> --- a/drivers/regulator/palmas-regulator.c
> +++ b/drivers/regulator/palmas-regulator.c
> @@ -373,11 +373,22 @@ static int palmas_set_voltage_smps_sel(struct regulator_dev *dev,
> static int palmas_map_voltage_smps(struct regulator_dev *rdev,
> int min_uV, int max_uV)
> {
> + struct palmas_pmic *pmic = rdev_get_drvdata(rdev);
> + int id = rdev_get_id(rdev);
> int ret, voltage;
>
> - ret = ((min_uV - 500000) / 10000) + 1;
> - if (ret < 0)
> - return ret;
> + if (min_uV == 0)
> + return 0;
> +
> + if (pmic->range[id]) { /* RANGE is x2 */
> + if (min_uV < 1000000)
> + min_uV = 1000000;
> + ret = DIV_ROUND_UP(min_uV - 1000000, 20000) + 1;
> + } else { /* RANGE is x1 */
> + if (min_uV < 500000)
> + min_uV = 500000;
> + ret = DIV_ROUND_UP(min_uV - 500000, 10000) + 1;
> + }
>
> /* Map back into a voltage to verify we're still in bounds */
> voltage = palmas_list_voltage_smps(rdev, ret);


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