Re: [PATCH v3 13/23] input: add max77705 haptic driver

Krzysztof Kozlowski
2024-06-20T16:05:11Z

On 18/06/2024 15:59, Dzmitry Sankouski wrote:
> Add support for haptic controller on MAX77705 Multifunction
> device.
>
> This driver supports external pwm and LRA (Linear Resonant Actuator) motor.
> User can control the haptic device via force feedback framework.
>
> Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
> ---

> +static int max77705_haptic_bias(struct max77705_haptic *haptic, bool on)
> +{
> + int error;
> +
> + error = regmap_update_bits(haptic->regmap_haptic,
> + MAX77705_PMIC_REG_MAINCTRL1,
> + MAX77705_MAINCTRL1_BIASEN_MASK,
> + on << MAX77705_MAINCTRL1_BIASEN_SHIFT);
> +
> + if (error) {
> + dev_err(haptic->dev, "failed to %s bias: %d\n",
> + on ? "enable" : "disable", error);
> + return error;
> + }
> +
> + return 0;
> +}
> +
> +static int max77705_haptic_configure(struct max77705_haptic *haptic,
> + bool enable)
> +{
> + unsigned int value, config_reg;
> + int error;
> +
> + value = ((haptic->type << MAX77705_CONFIG2_MODE_SHIFT) |
> + (enable << MAX77705_CONFIG2_MEN_SHIFT) |
> + (haptic->mode << MAX77705_CONFIG2_HTYP_SHIFT) |
> + MAX77705_HAPTIC_PWM_DIVISOR_128);
> + config_reg = MAX77705_PMIC_REG_MCONFIG;
> +
> + error = regmap_write(haptic->regmap_haptic,
> + config_reg, value);
> + if (error) {
> + dev_err(haptic->dev,
> + "failed to update haptic config: %d\n", error);
> + return error;
> + }
> +
> + return 0;
> +}
> +
> +static void max77705_haptic_enable(struct max77705_haptic *haptic)
> +{
> + int error;
> +
> + if (haptic->enabled)
> + return;
> +
> + error = pwm_enable(haptic->pwm_dev);
> + if (error) {
> + dev_err(haptic->dev,
> + "failed to enable haptic pwm device: %d\n", error);
> + return;
> + }
> +
> + error = max77705_haptic_configure(haptic, true);
> + if (error)
> + goto err_enable_config;
> +
> + haptic->enabled = true;
> +
> + return;
> +
> +err_enable_config:
> + pwm_disable(haptic->pwm_dev);
> +}
> +
> +static void max77705_haptic_disable(struct max77705_haptic *haptic)
> +{
> + int error;
> +
> + if (!haptic->enabled)
> + return;
> +
> + error = max77705_haptic_configure(haptic, false);
> + if (error)
> + return;
> +
> + pwm_disable(haptic->pwm_dev);
> + haptic->enabled = false;
> +}
> +
> +static void max77705_haptic_play_work(struct work_struct *work)
> +{
> + struct max77705_haptic *haptic =
> + container_of(work, struct max77705_haptic, work);
> + int error;
> +
> + error = max77705_haptic_set_duty_cycle(haptic);
> + if (error) {
> + dev_err(haptic->dev, "failed to set duty cycle: %d\n", error);
> + return;
> + }
> +
> + if (haptic->magnitude)
> + max77705_haptic_enable(haptic);
> + else
> + max77705_haptic_disable(haptic);
> +}
> +
> +static int max77705_haptic_play_effect(struct input_dev *dev, void *data,
> + struct ff_effect *effect)
> +{
> + struct max77705_haptic *haptic = input_get_drvdata(dev);
> + struct pwm_args pargs;
> + u64 period_mag_multi;
> +
> + haptic->magnitude = effect->u.rumble.strong_magnitude;
> + if (!haptic->magnitude)
> + haptic->magnitude = effect->u.rumble.weak_magnitude;
> +
> + /*
> + * The magnitude comes from force-feedback interface.
> + * The formula to convert magnitude to pwm_duty as follows:
> + * - pwm_duty = (magnitude * pwm_period) / MAX_MAGNITUDE(0xFFFF)
> + */
> + pr_info("magnitude: %d(%x)", haptic->magnitude, haptic->magnitude);

Do not use pr_xxx in your drivers. That's a generic comment so please
apply it everywhere. Anyway driver should be silent.

> + pwm_get_args(haptic->pwm_dev, &pargs);
> + period_mag_multi = (u64)pargs.period * haptic->magnitude;
> + haptic->pwm_duty = (unsigned int)(period_mag_multi >>
> + MAX_MAGNITUDE_SHIFT);
> +
> + schedule_work(&haptic->work);
> +
> + return 0;
> +}

> +
> +static DEFINE_SIMPLE_DEV_PM_OPS(max77705_haptic_pm_ops,
> + max77705_haptic_suspend,
> + max77705_haptic_resume);
> +
> +static const struct of_device_id of_max77705_haptic_dt_match[] = {
> + { .compatible = "maxim,max77705-haptic", },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, of_max77705_haptic_dt_match);
> +
> +static struct platform_driver max77705_haptic_driver = {
> + .driver = {
> + .name = "max77705-haptic",
> + .pm = pm_sleep_ptr(&max77705_haptic_pm_ops),
> + .of_match_table = of_max77705_haptic_dt_match,
> + },
> + .probe = max77705_haptic_probe,
> + .remove_new = max77705_haptic_remove,
> +};
> +module_platform_driver(max77705_haptic_driver);
> +
> +MODULE_AUTHOR("Dzmitry Sankouski <dsankouski@gmail.com>");
> +MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
> +MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");

I doubt that this driver is needed. Everything is copy of max777693.

Best regards,
Krzysztof