From pavel@ucw.cz Fri Aug 7 13:41:27 2009 From: Pavel Machek Date: Wed, 5 Aug 2009 00:00:10 +0200 Subject: Staging: dream: synaptics touchscreen for dream: documentation To: Greg KH Cc: Message-ID: <20090804220009.GA2077@elf.ucw.cz> Content-Disposition: inline This adds pointer to hardware documentation, and adds code comment from Arve. Signed-off-by: Pavel Machek Signed-off-by: Greg Kroah-Hartman --- drivers/staging/dream/synaptics_i2c_rmi.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) --- a/drivers/staging/dream/synaptics_i2c_rmi.c +++ b/drivers/staging/dream/synaptics_i2c_rmi.c @@ -13,6 +13,7 @@ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * + * http://www.synaptics.com/sites/default/files/511_000099_01F.pdf */ #include @@ -87,6 +88,22 @@ static int synaptics_init_panel(struct s static void decode_report(struct synaptics_ts_data *ts, u8 *buf) { +/* + * This sensor sends two 6-byte absolute finger reports, an optional + * 2-byte relative report followed by a status byte. This function + * reads the two finger reports and transforms the coordinates + * according the platform data so they can be aligned with the lcd + * behind the touchscreen. Typically we flip the y-axis since the + * sensor uses the bottom left corner as the origin, but if the sensor + * is mounted upside down the platform data will request that the + * x-axis should be flipped instead. The snap to inactive edge border + * are used to allow tapping the edges of the screen on the G1. The + * active area of the touchscreen is smaller than the lcd. When the + * finger gets close the edge of the screen we snap it to the + * edge. This allows ui elements at the edge of the screen to be hit, + * and it prevents hitting ui elements that are not at the edge of the + * screen when the finger is touching the edge. + */ int pos[2][2]; int f, a; int base = 2;