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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/hid/i2c-hid/i2c-hid-of-elan.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hid/i2c-hid/i2c-hid-of-elan.c')
-rw-r--r--drivers/hid/i2c-hid/i2c-hid-of-elan.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/drivers/hid/i2c-hid/i2c-hid-of-elan.c b/drivers/hid/i2c-hid/i2c-hid-of-elan.c
new file mode 100644
index 000000000..2d991325e
--- /dev/null
+++ b/drivers/hid/i2c-hid/i2c-hid-of-elan.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Elan touchscreens that use the i2c-hid protocol.
+ *
+ * Copyright 2020 Google LLC
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/regulator/consumer.h>
+
+#include "i2c-hid.h"
+
+struct elan_i2c_hid_chip_data {
+ unsigned int post_gpio_reset_delay_ms;
+ unsigned int post_power_delay_ms;
+ u16 hid_descriptor_address;
+};
+
+struct i2c_hid_of_elan {
+ struct i2chid_ops ops;
+
+ struct regulator *vcc33;
+ struct regulator *vccio;
+ struct gpio_desc *reset_gpio;
+ const struct elan_i2c_hid_chip_data *chip_data;
+};
+
+static int elan_i2c_hid_power_up(struct i2chid_ops *ops)
+{
+ struct i2c_hid_of_elan *ihid_elan =
+ container_of(ops, struct i2c_hid_of_elan, ops);
+ int ret;
+
+ ret = regulator_enable(ihid_elan->vcc33);
+ if (ret)
+ return ret;
+
+ ret = regulator_enable(ihid_elan->vccio);
+ if (ret) {
+ regulator_disable(ihid_elan->vcc33);
+ return ret;
+ }
+
+ if (ihid_elan->chip_data->post_power_delay_ms)
+ msleep(ihid_elan->chip_data->post_power_delay_ms);
+
+ gpiod_set_value_cansleep(ihid_elan->reset_gpio, 0);
+ if (ihid_elan->chip_data->post_gpio_reset_delay_ms)
+ msleep(ihid_elan->chip_data->post_gpio_reset_delay_ms);
+
+ return 0;
+}
+
+static void elan_i2c_hid_power_down(struct i2chid_ops *ops)
+{
+ struct i2c_hid_of_elan *ihid_elan =
+ container_of(ops, struct i2c_hid_of_elan, ops);
+
+ gpiod_set_value_cansleep(ihid_elan->reset_gpio, 1);
+ regulator_disable(ihid_elan->vccio);
+ regulator_disable(ihid_elan->vcc33);
+}
+
+static int i2c_hid_of_elan_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct i2c_hid_of_elan *ihid_elan;
+
+ ihid_elan = devm_kzalloc(&client->dev, sizeof(*ihid_elan), GFP_KERNEL);
+ if (!ihid_elan)
+ return -ENOMEM;
+
+ ihid_elan->ops.power_up = elan_i2c_hid_power_up;
+ ihid_elan->ops.power_down = elan_i2c_hid_power_down;
+
+ /* Start out with reset asserted */
+ ihid_elan->reset_gpio =
+ devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(ihid_elan->reset_gpio))
+ return PTR_ERR(ihid_elan->reset_gpio);
+
+ ihid_elan->vccio = devm_regulator_get(&client->dev, "vccio");
+ if (IS_ERR(ihid_elan->vccio))
+ return PTR_ERR(ihid_elan->vccio);
+
+ ihid_elan->vcc33 = devm_regulator_get(&client->dev, "vcc33");
+ if (IS_ERR(ihid_elan->vcc33))
+ return PTR_ERR(ihid_elan->vcc33);
+
+ ihid_elan->chip_data = device_get_match_data(&client->dev);
+
+ return i2c_hid_core_probe(client, &ihid_elan->ops,
+ ihid_elan->chip_data->hid_descriptor_address, 0);
+}
+
+static const struct elan_i2c_hid_chip_data elan_ekth6915_chip_data = {
+ .post_power_delay_ms = 1,
+ .post_gpio_reset_delay_ms = 300,
+ .hid_descriptor_address = 0x0001,
+};
+
+static const struct of_device_id elan_i2c_hid_of_match[] = {
+ { .compatible = "elan,ekth6915", .data = &elan_ekth6915_chip_data },
+ { }
+};
+MODULE_DEVICE_TABLE(of, elan_i2c_hid_of_match);
+
+static struct i2c_driver elan_i2c_hid_ts_driver = {
+ .driver = {
+ .name = "i2c_hid_of_elan",
+ .pm = &i2c_hid_core_pm,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ .of_match_table = of_match_ptr(elan_i2c_hid_of_match),
+ },
+ .probe = i2c_hid_of_elan_probe,
+ .remove = i2c_hid_core_remove,
+ .shutdown = i2c_hid_core_shutdown,
+};
+module_i2c_driver(elan_i2c_hid_ts_driver);
+
+MODULE_AUTHOR("Douglas Anderson <dianders@chromium.org>");
+MODULE_DESCRIPTION("Elan i2c-hid touchscreen driver");
+MODULE_LICENSE("GPL");