Re: [PATCH v2 09/24] input: Port hid-dr to ff-memless-next

From: Oliver Neukum
Date: Wed Apr 23 2014 - 09:41:14 EST


On Tue, 2014-04-22 at 15:59 +0200, Michal Malà wrote:
> static int drff_play(struct input_dev *dev, void *data,
> - struct ff_effect *effect)
> + const struct mlnx_effect_command *command)
> {
> struct hid_device *hid = input_get_drvdata(dev);
> struct drff_device *drff = data;
> + const struct mlnx_rumble_force *rumble_force =
> &command->u.rumble_force;
> int strong, weak;
>
> - strong = effect->u.rumble.strong_magnitude;
> - weak = effect->u.rumble.weak_magnitude;
> + strong = rumble_force->strong;
> + weak = rumble_force->weak;
>
> dbg_hid("called with 0x%04x 0x%04x", strong, weak);
>
> - if (strong || weak) {
> - strong = strong * 0xff / 0xffff;
> - weak = weak * 0xff / 0xffff;
> -
> - /* While reverse engineering this device, I found that
> when
> - this value is set, it causes the strong rumble to
> function
> - at a near maximum speed, so we'll bypass it. */
> - if (weak == 0x0a)
> - weak = 0x0b;
> -
> - drff->report->field[0]->value[0] = 0x51;
> - drff->report->field[0]->value[1] = 0x00;
> - drff->report->field[0]->value[2] = weak;
> - drff->report->field[0]->value[4] = strong;
> - hid_hw_request(hid, drff->report, HID_REQ_SET_REPORT);
> -
> - drff->report->field[0]->value[0] = 0xfa;
> - drff->report->field[0]->value[1] = 0xfe;
> - } else {
> + switch (command->cmd) {
> + case MLNX_START_RUMBLE:
> + if (strong || weak) {
> + strong = strong * 0xff / 0xffff;
> + weak = weak * 0xff / 0xffff;
> +
> + /* While reverse engineering this device, I
> found that when
> + this value is set, it causes the strong rumble
> to function
> + at a near maximum speed, so we'll bypass it.
> */
> + if (weak == 0x0a)
> + weak = 0x0b;
> +
> + drff->report->field[0]->value[0] = 0x51;
> + drff->report->field[0]->value[1] = 0x00;
> + drff->report->field[0]->value[2] = weak;
> + drff->report->field[0]->value[4] = strong;

This looks like an endianness bug.

> + hid_hw_request(hid, drff->report,
> HID_REQ_SET_REPORT);

Regards
Oliver


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