summaryrefslogtreecommitdiffstats
path: root/drivers/input
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-18 11:00:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-18 11:00:00 -0700
commit2475c515d4031c494ff452508a8bf8c281ec6e56 (patch)
tree0303935bbd919ec522bf0fe02066f09b391d2b57 /drivers/input
parent336722eb9d9732c5a497fb6299bf38cde413592b (diff)
parente4f6a44c4aeca9eda153302abb0c14d053914f72 (diff)
downloadlinux-2475c515d4031c494ff452508a8bf8c281ec6e56.tar.bz2
Merge tag 'staging-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO updates from Greg KH: "Here are the big staging/iio patches for 4.19-rc1. Lots of churn here, with tons of cleanups happening in staging drivers, a removal of an old crypto driver that no one was using (skein), and the addition of some new IIO drivers. Also added was a "gasket" driver from Google that needs loads of work and the erofs filesystem. Even with adding all of the new drivers and a new filesystem, we are only adding about 1000 lines overall to the kernel linecount, which shows just how much cleanup happened, and how big the unused crypto driver was. All of these have been in the linux-next tree for a while now with no reported issues" * tag 'staging-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (903 commits) staging:rtl8192u: Remove unused macro definitions - Style staging:rtl8192u: Add spaces around '+' operator - Style staging:rtl8192u: Remove stale comment - Style staging: rtl8188eu: remove unused mp_custom_oid.h staging: fbtft: Add spaces around / - Style staging: fbtft: Erases some repetitive usage of function name - Style staging: fbtft: Adjust some empty-line problems - Style staging: fbtft: Removes one nesting level to help readability - Style staging: fbtft: Changes gamma table to define. staging: fbtft: A bit more information on dev_err. staging: fbtft: Fixes some alignment issues - Style staging: fbtft: Puts macro arguments in parenthesis to avoid precedence issues - Style staging: rtl8188eu: remove unused array dB_Invert_Table staging: rtl8188eu: remove whitespace, add missing blank line staging: rtl8188eu: use is_multicast_ether_addr in rtw_sta_mgt.c staging: rtl8188eu: remove whitespace - style staging: rtl8188eu: cleanup block comment - style staging: rtl8188eu: use is_multicast_ether_addr in rtl8188eu_xmit.c staging: rtl8188eu: use is_multicast_ether_addr in recv_linux.c staging: rtlwifi: refactor rtl_get_tcb_desc ...
Diffstat (limited to 'drivers/input')
-rw-r--r--drivers/input/touchscreen/Kconfig13
-rw-r--r--drivers/input/touchscreen/Makefile1
-rw-r--r--drivers/input/touchscreen/resistive-adc-touch.c204
3 files changed, 218 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 32267c1afebc..66d1a220726a 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -92,6 +92,19 @@ config TOUCHSCREEN_AD7879_SPI
To compile this driver as a module, choose M here: the
module will be called ad7879-spi.
+config TOUCHSCREEN_ADC
+ tristate "Generic ADC based resistive touchscreen"
+ depends on IIO
+ select IIO_BUFFER_CB
+ help
+ Say Y here if you want to use the generic ADC
+ resistive touchscreen driver.
+
+ If unsure, say N (but it's safe to say "Y").
+
+ To compile this driver as a module, choose M here: the
+ module will be called resistive-adc-touch.ko.
+
config TOUCHSCREEN_AR1021_I2C
tristate "Microchip AR1020/1021 i2c touchscreen"
depends on I2C && OF
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index fd4fd32fb73f..35bd0619edf1 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_TOUCHSCREEN_AD7877) += ad7877.o
obj-$(CONFIG_TOUCHSCREEN_AD7879) += ad7879.o
obj-$(CONFIG_TOUCHSCREEN_AD7879_I2C) += ad7879-i2c.o
obj-$(CONFIG_TOUCHSCREEN_AD7879_SPI) += ad7879-spi.o
+obj-$(CONFIG_TOUCHSCREEN_ADC) += resistive-adc-touch.o
obj-$(CONFIG_TOUCHSCREEN_ADS7846) += ads7846.o
obj-$(CONFIG_TOUCHSCREEN_AR1021_I2C) += ar1021_i2c.o
obj-$(CONFIG_TOUCHSCREEN_ATMEL_MXT) += atmel_mxt_ts.o
diff --git a/drivers/input/touchscreen/resistive-adc-touch.c b/drivers/input/touchscreen/resistive-adc-touch.c
new file mode 100644
index 000000000000..cfc8bb4553f7
--- /dev/null
+++ b/drivers/input/touchscreen/resistive-adc-touch.c
@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ADC generic resistive touchscreen (GRTS)
+ * This is a generic input driver that connects to an ADC
+ * given the channels in device tree, and reports events to the input
+ * subsystem.
+ *
+ * Copyright (C) 2017,2018 Microchip Technology,
+ * Author: Eugen Hristev <eugen.hristev@microchip.com>
+ *
+ */
+#include <linux/input.h>
+#include <linux/input/touchscreen.h>
+#include <linux/iio/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+#define DRIVER_NAME "resistive-adc-touch"
+#define GRTS_DEFAULT_PRESSURE_MIN 50000
+#define GRTS_MAX_POS_MASK GENMASK(11, 0)
+
+/**
+ * grts_state - generic resistive touch screen information struct
+ * @pressure_min: number representing the minimum for the pressure
+ * @pressure: are we getting pressure info or not
+ * @iio_chans: list of channels acquired
+ * @iio_cb: iio_callback buffer for the data
+ * @input: the input device structure that we register
+ * @prop: touchscreen properties struct
+ */
+struct grts_state {
+ u32 pressure_min;
+ bool pressure;
+ struct iio_channel *iio_chans;
+ struct iio_cb_buffer *iio_cb;
+ struct input_dev *input;
+ struct touchscreen_properties prop;
+};
+
+static int grts_cb(const void *data, void *private)
+{
+ const u16 *touch_info = data;
+ struct grts_state *st = private;
+ unsigned int x, y, press = 0x0;
+
+ /* channel data coming in buffer in the order below */
+ x = touch_info[0];
+ y = touch_info[1];
+ if (st->pressure)
+ press = touch_info[2];
+
+ if ((!x && !y) || (st->pressure && (press < st->pressure_min))) {
+ /* report end of touch */
+ input_report_key(st->input, BTN_TOUCH, 0);
+ input_sync(st->input);
+ return 0;
+ }
+
+ /* report proper touch to subsystem*/
+ touchscreen_report_pos(st->input, &st->prop, x, y, false);
+ if (st->pressure)
+ input_report_abs(st->input, ABS_PRESSURE, press);
+ input_report_key(st->input, BTN_TOUCH, 1);
+ input_sync(st->input);
+
+ return 0;
+}
+
+static int grts_open(struct input_dev *dev)
+{
+ int error;
+ struct grts_state *st = input_get_drvdata(dev);
+
+ error = iio_channel_start_all_cb(st->iio_cb);
+ if (error) {
+ dev_err(dev->dev.parent, "failed to start callback buffer.\n");
+ return error;
+ }
+ return 0;
+}
+
+static void grts_close(struct input_dev *dev)
+{
+ struct grts_state *st = input_get_drvdata(dev);
+
+ iio_channel_stop_all_cb(st->iio_cb);
+}
+
+static void grts_disable(void *data)
+{
+ iio_channel_release_all_cb(data);
+}
+
+static int grts_probe(struct platform_device *pdev)
+{
+ struct grts_state *st;
+ struct input_dev *input;
+ struct device *dev = &pdev->dev;
+ struct iio_channel *chan;
+ int error;
+
+ st = devm_kzalloc(dev, sizeof(struct grts_state), GFP_KERNEL);
+ if (!st)
+ return -ENOMEM;
+
+ /* get the channels from IIO device */
+ st->iio_chans = devm_iio_channel_get_all(dev);
+ if (IS_ERR(st->iio_chans)) {
+ error = PTR_ERR(st->iio_chans);
+ if (error != -EPROBE_DEFER)
+ dev_err(dev, "can't get iio channels.\n");
+ return error;
+ }
+
+ chan = &st->iio_chans[0];
+ st->pressure = false;
+ while (chan && chan->indio_dev) {
+ if (!strcmp(chan->channel->datasheet_name, "pressure"))
+ st->pressure = true;
+ chan++;
+ }
+
+ if (st->pressure) {
+ error = device_property_read_u32(dev,
+ "touchscreen-min-pressure",
+ &st->pressure_min);
+ if (error) {
+ dev_dbg(dev, "can't get touchscreen-min-pressure property.\n");
+ st->pressure_min = GRTS_DEFAULT_PRESSURE_MIN;
+ }
+ }
+
+ input = devm_input_allocate_device(dev);
+ if (!input) {
+ dev_err(dev, "failed to allocate input device.\n");
+ return -ENOMEM;
+ }
+
+ input->name = DRIVER_NAME;
+ input->id.bustype = BUS_HOST;
+ input->open = grts_open;
+ input->close = grts_close;
+
+ input_set_abs_params(input, ABS_X, 0, GRTS_MAX_POS_MASK - 1, 0, 0);
+ input_set_abs_params(input, ABS_Y, 0, GRTS_MAX_POS_MASK - 1, 0, 0);
+ if (st->pressure)
+ input_set_abs_params(input, ABS_PRESSURE, st->pressure_min,
+ 0xffff, 0, 0);
+
+ input_set_capability(input, EV_KEY, BTN_TOUCH);
+
+ /* parse optional device tree properties */
+ touchscreen_parse_properties(input, false, &st->prop);
+
+ st->input = input;
+ input_set_drvdata(input, st);
+
+ error = input_register_device(input);
+ if (error) {
+ dev_err(dev, "failed to register input device.");
+ return error;
+ }
+
+ st->iio_cb = iio_channel_get_all_cb(dev, grts_cb, st);
+ if (IS_ERR(st->iio_cb)) {
+ dev_err(dev, "failed to allocate callback buffer.\n");
+ return PTR_ERR(st->iio_cb);
+ }
+
+ error = devm_add_action_or_reset(dev, grts_disable, st->iio_cb);
+ if (error) {
+ dev_err(dev, "failed to add disable action.\n");
+ return error;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id grts_of_match[] = {
+ {
+ .compatible = "resistive-adc-touch",
+ }, {
+ /* sentinel */
+ },
+};
+
+MODULE_DEVICE_TABLE(of, grts_of_match);
+
+static struct platform_driver grts_driver = {
+ .probe = grts_probe,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = of_match_ptr(grts_of_match),
+ },
+};
+
+module_platform_driver(grts_driver);
+
+MODULE_AUTHOR("Eugen Hristev <eugen.hristev@microchip.com>");
+MODULE_DESCRIPTION("Generic ADC Resistive Touch Driver");
+MODULE_LICENSE("GPL v2");