On 10/27/2016 05:33 AM, Bastien Nocera wrote: > On Thu, 2016-10-20 at 14:59 -0500, Franklin S Cooper Jr wrote: >> Some goodix touchscreen controllers don't have the correct >> configuration >> firmware for the display panel it is attached to. Therefore, settings >> such >> as touchscreen x and y size may need to be passed in via DT and have >> the >> panel reprogrammed for the updated touchscreen resolution. >> >> This patchset adds support for reading the current configuration >> firmware >> on the panel and allowing it to be modified and rewritten back to the >> device. >> >> Currently this function is unused but later patches will make use of >> it. >> >> Signed-off-by: Franklin S Cooper Jr <[email protected]> >> --- >> drivers/input/touchscreen/goodix.c | 28 ++++++++++++++++++++++++++++ >> 1 file changed, 28 insertions(+) >> >> diff --git a/drivers/input/touchscreen/goodix.c >> b/drivers/input/touchscreen/goodix.c >> index a43c8ca..01e12f8 100644 >> --- a/drivers/input/touchscreen/goodix.c >> +++ b/drivers/input/touchscreen/goodix.c >> @@ -478,6 +478,34 @@ static int goodix_get_gpio_config(struct >> goodix_ts_data *ts) >> return 0; >> } >> >> +static void goodix_tweak_config(struct goodix_ts_data *ts) >> +{ >> + u8 config[GOODIX_CONFIG_MAX_LENGTH]; >> + int error; >> + int raw_cfg_len; >> + u8 check_sum = 0; >> + >> + raw_cfg_len = ts->cfg_len - 2; >> + >> + error = goodix_i2c_read(ts->client, GOODIX_REG_CONFIG_DATA, >> + config, ts->cfg_len); >> + if (error) { >> + dev_warn(&ts->client->dev, >> + "Error reading config (%d), avoid tweaking >> config\n", >> + error); >> + return; >> + } > > Please add a placeholder comment here, to go along with the commit > message explanation.
You just want a comment here stating that changes to the firmware should be made here? > >> + check_sum = goodix_calculate_checksum(ts->cfg_len, config); >> + >> + config[raw_cfg_len] = check_sum; >> + config[raw_cfg_len + 1] = 1; >> + >> + error = goodix_send_cfg(ts, ts->cfg_len, config); >> + if (error) >> + dev_warn(&ts->client->dev, >> + "Error writing config (%d)\n", error); >> +} >> /** >> * goodix_read_config - Read the embedded configuration of the panel >> *
