1 // SPDX-License-Identifier: GPL-2.0
3  * ADC generic resistive touchscreen (GRTS)
13 #include <linux/input/touchscreen.h>
21 #define DRIVER_NAME					"resistive-adc-touch"
26  * grts_state - generic resistive touch screen information struct
32  * @prop:		touchscreen properties struct
47 	unsigned int x, y, press = 0x0;  in grts_cb()  local
50 	x = touch_info[0];  in grts_cb()
52 	if (st->pressure)  in grts_cb()
55 	if ((!x && !y) || (st->pressure && (press < st->pressure_min))) {  in grts_cb()
57 		input_report_key(st->input, BTN_TOUCH, 0);  in grts_cb()
58 		input_sync(st->input);  in grts_cb()
63 	touchscreen_report_pos(st->input, &st->prop, x, y, false);  in grts_cb()
64 	if (st->pressure)  in grts_cb()
65 		input_report_abs(st->input, ABS_PRESSURE, press);  in grts_cb()
66 	input_report_key(st->input, BTN_TOUCH, 1);  in grts_cb()
67 	input_sync(st->input);  in grts_cb()
77 	error = iio_channel_start_all_cb(st->iio_cb);  in grts_open()
79 		dev_err(dev->dev.parent, "failed to start callback buffer.\n");  in grts_open()
89 	iio_channel_stop_all_cb(st->iio_cb);  in grts_close()
101 	struct device *dev = &pdev->dev;  in grts_probe()
107 		return -ENOMEM;  in grts_probe()
110 	st->iio_chans = devm_iio_channel_get_all(dev);  in grts_probe()
111 	if (IS_ERR(st->iio_chans)) {  in grts_probe()
112 		error = PTR_ERR(st->iio_chans);  in grts_probe()
113 		if (error != -EPROBE_DEFER)  in grts_probe()
118 	chan = &st->iio_chans[0];  in grts_probe()
119 	st->pressure = false;  in grts_probe()
120 	while (chan && chan->indio_dev) {  in grts_probe()
121 		if (!strcmp(chan->channel->datasheet_name, "pressure"))  in grts_probe()
122 			st->pressure = true;  in grts_probe()
126 	if (st->pressure) {  in grts_probe()
128 						 "touchscreen-min-pressure",  in grts_probe()
129 						 &st->pressure_min);  in grts_probe()
131 			dev_dbg(dev, "can't get touchscreen-min-pressure property.\n");  in grts_probe()
132 			st->pressure_min = GRTS_DEFAULT_PRESSURE_MIN;  in grts_probe()
139 		return -ENOMEM;  in grts_probe()
142 	input->name = DRIVER_NAME;  in grts_probe()
143 	input->id.bustype = BUS_HOST;  in grts_probe()
144 	input->open = grts_open;  in grts_probe()
145 	input->close = grts_close;  in grts_probe()
147 	input_set_abs_params(input, ABS_X, 0, GRTS_MAX_POS_MASK - 1, 0, 0);  in grts_probe()
148 	input_set_abs_params(input, ABS_Y, 0, GRTS_MAX_POS_MASK - 1, 0, 0);  in grts_probe()
149 	if (st->pressure)  in grts_probe()
150 		input_set_abs_params(input, ABS_PRESSURE, st->pressure_min,  in grts_probe()
156 	touchscreen_parse_properties(input, false, &st->prop);  in grts_probe()
158 	st->input = input;  in grts_probe()
167 	st->iio_cb = iio_channel_get_all_cb(dev, grts_cb, st);  in grts_probe()
168 	if (IS_ERR(st->iio_cb)) {  in grts_probe()
170 		return PTR_ERR(st->iio_cb);  in grts_probe()
173 	error = devm_add_action_or_reset(dev, grts_disable, st->iio_cb);  in grts_probe()
184 		.compatible = "resistive-adc-touch",