"Scrolling acceleration" is a bit of a misnomer: it doesn't deal with acceleration at all. However, that's the name used in Logitech's spec, so I used it here. Signed-off-by: Harry Cutts <hcutts@xxxxxxxxxxxx> --- Changes in v2: None drivers/hid/hid-logitech-hidpp.c | 47 +++++++++++++++++++++++--------- 1 file changed, 34 insertions(+), 13 deletions(-) diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index 19cc980eebce..7f8218f6ff56 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -400,32 +400,53 @@ static void hidpp_prefix_name(char **name, int name_length) #define HIDPP_SET_LONG_REGISTER 0x82 #define HIDPP_GET_LONG_REGISTER 0x83 -#define HIDPP_REG_GENERAL 0x00 - -static int hidpp10_enable_battery_reporting(struct hidpp_device *hidpp_dev) +/** + * hidpp10_set_register_bit() - Sets a single bit in a HID++ 1.0 register. + * @hidpp_dev: the device to set the register on. + * @register_address: the address of the register to modify. + * @byte: the byte of the register to modify. Should be less than 3. + * Return: 0 if successful, otherwise a negative error code. + */ +static int hidpp10_set_register_bit(struct hidpp_device *hidpp_dev, + u8 register_address, u8 byte, u8 bit) { struct hidpp_report response; int ret; u8 params[3] = { 0 }; ret = hidpp_send_rap_command_sync(hidpp_dev, - REPORT_ID_HIDPP_SHORT, - HIDPP_GET_REGISTER, - HIDPP_REG_GENERAL, - NULL, 0, &response); + REPORT_ID_HIDPP_SHORT, + HIDPP_GET_REGISTER, + register_address, + NULL, 0, &response); if (ret) return ret; memcpy(params, response.rap.params, 3); - /* Set the battery bit */ - params[0] |= BIT(4); + params[byte] |= BIT(bit); return hidpp_send_rap_command_sync(hidpp_dev, - REPORT_ID_HIDPP_SHORT, - HIDPP_SET_REGISTER, - HIDPP_REG_GENERAL, - params, 3, &response); + REPORT_ID_HIDPP_SHORT, + HIDPP_SET_REGISTER, + register_address, + params, 3, &response); +} + + +#define HIDPP_REG_GENERAL 0x00 + +static int hidpp10_enable_battery_reporting(struct hidpp_device *hidpp_dev) +{ + return hidpp10_set_register_bit(hidpp_dev, HIDPP_REG_GENERAL, 0, 4); +} + +#define HIDPP_REG_FEATURES 0x01 + +/* On HID++ 1.0 devices, high-res scroll was called "scrolling acceleration". */ +static int hidpp10_enable_scrolling_acceleration(struct hidpp_device *hidpp_dev) +{ + return hidpp10_set_register_bit(hidpp_dev, HIDPP_REG_FEATURES, 0, 6); } #define HIDPP_REG_BATTERY_STATUS 0x07 -- 2.19.0.rc0.228.g281dcd1b4d0-goog