Currently PWM regulator support the multiple voltage by two different mechanism: Voltage table based and continuous steps which divides duty cycle into 100 parts.
There is a use cases where entire voltage ranges from minimum to maximum is divided into n equal steps and just providing the steps count, the voltage table with duty cycles is linearly calculated. Add support to have specified linear n equal steps for specified regulator's minimum and maximum voltage range for PWM regulators. Signed-off-by: Laxman Dewangan <[email protected]> Cc: Lee Jones <[email protected]> --- drivers/regulator/pwm-regulator.c | 76 ++++++++++++++++++++++++++++++++++----- 1 file changed, 68 insertions(+), 8 deletions(-) diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c index 9db67a1..060e5cf 100644 --- a/drivers/regulator/pwm-regulator.c +++ b/drivers/regulator/pwm-regulator.c @@ -38,6 +38,9 @@ struct pwm_regulator_data { /* Continuous voltage */ int volt_uV; + + /* Regulator n linear steps */ + unsigned int regulator_n_steps; }; struct pwm_voltages { @@ -65,7 +68,11 @@ static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev, pwm_reg_period = pwm_get_period(drvdata->pwm); - dutycycle = (pwm_reg_period * + if (drvdata->regulator_n_steps) + dutycycle = (pwm_reg_period * selector) / + (drvdata->regulator_n_steps - 1); + else + dutycycle = (pwm_reg_period * drvdata->duty_cycle_table[selector].dutycycle) / 100; ret = pwm_config(drvdata->pwm, dutycycle, pwm_reg_period); @@ -227,6 +234,41 @@ static int pwm_regulator_init_table(struct platform_device *pdev, return 0; } +static int pwm_regulator_init_linear_steps(struct platform_device *pdev, + struct pwm_regulator_data *drvdata) +{ + struct device_node *np = pdev->dev.of_node; + unsigned int period; + u32 uval; + int ret; + + ret = of_property_read_u32(np, "regulator-n-voltages", &uval); + if (ret < 0) + return ret; + if (uval < 2) { + dev_err(&pdev->dev, "Invalid number of voltage steps\n"); + return -EINVAL; + } + + period = pwm_get_period(drvdata->pwm); + if (period % (uval - 1)) { + dev_err(&pdev->dev, "PWM Period must multiple of n_voltages\n"); + return -EINVAL; + } + + memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops, + sizeof(drvdata->ops)); + drvdata->ops.list_voltage = regulator_list_voltage_linear; + drvdata->ops.map_voltage = regulator_map_voltage_linear; + + drvdata->regulator_n_steps = uval; + drvdata->desc.ops = &drvdata->ops; + drvdata->desc.linear_min_sel = 0; + drvdata->desc.n_voltages = drvdata->regulator_n_steps; + + return 0; +} + static int pwm_regulator_init_continuous(struct platform_device *pdev, struct pwm_regulator_data *drvdata) { @@ -256,10 +298,19 @@ static int pwm_regulator_probe(struct platform_device *pdev) if (!drvdata) return -ENOMEM; + drvdata->pwm = devm_pwm_get(&pdev->dev, NULL); + if (IS_ERR(drvdata->pwm)) { + ret = PTR_ERR(drvdata->pwm); + dev_err(&pdev->dev, "Failed to get PWM, %d\n", ret); + return ret; + } + memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc)); if (of_find_property(np, "voltage-table", NULL)) ret = pwm_regulator_init_table(pdev, drvdata); + else if (of_find_property(np, "regulator-n-voltages", NULL)) + ret = pwm_regulator_init_linear_steps(pdev, drvdata); else ret = pwm_regulator_init_continuous(pdev, drvdata); if (ret) @@ -270,18 +321,27 @@ static int pwm_regulator_probe(struct platform_device *pdev) if (!init_data) return -ENOMEM; + if (drvdata->regulator_n_steps) { + int min_uV = init_data->constraints.min_uV; + int max_uV = init_data->constraints.max_uV; + int step_uV; + + if ((max_uV - min_uV) % (drvdata->regulator_n_steps - 1)) { + dev_err(&pdev->dev, + "Min/Max is not proper to get step voltage\n"); + return -EINVAL; + } + + step_uV = (max_uV - min_uV) / (drvdata->regulator_n_steps - 1); + drvdata->desc.min_uV = min_uV; + drvdata->desc.uV_step = step_uV; + } + config.of_node = np; config.dev = &pdev->dev; config.driver_data = drvdata; config.init_data = init_data; - drvdata->pwm = devm_pwm_get(&pdev->dev, NULL); - if (IS_ERR(drvdata->pwm)) { - ret = PTR_ERR(drvdata->pwm); - dev_err(&pdev->dev, "Failed to get PWM, %d\n", ret); - return ret; - } - regulator = devm_regulator_register(&pdev->dev, &drvdata->desc, &config); if (IS_ERR(regulator)) { -- 2.1.4
