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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/input/keyboard/mpr121_touchkey.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/input/keyboard/mpr121_touchkey.c')
-rw-r--r--drivers/input/keyboard/mpr121_touchkey.c400
1 files changed, 400 insertions, 0 deletions
diff --git a/drivers/input/keyboard/mpr121_touchkey.c b/drivers/input/keyboard/mpr121_touchkey.c
new file mode 100644
index 000000000..230ab3d50
--- /dev/null
+++ b/drivers/input/keyboard/mpr121_touchkey.c
@@ -0,0 +1,400 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Touchkey driver for Freescale MPR121 Controllor
+ *
+ * Copyright (C) 2011 Freescale Semiconductor, Inc.
+ * Author: Zhang Jiejing <jiejing.zhang@freescale.com>
+ *
+ * Based on mcs_touchkey.c
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/property.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+/* Register definitions */
+#define ELE_TOUCH_STATUS_0_ADDR 0x0
+#define ELE_TOUCH_STATUS_1_ADDR 0X1
+#define MHD_RISING_ADDR 0x2b
+#define NHD_RISING_ADDR 0x2c
+#define NCL_RISING_ADDR 0x2d
+#define FDL_RISING_ADDR 0x2e
+#define MHD_FALLING_ADDR 0x2f
+#define NHD_FALLING_ADDR 0x30
+#define NCL_FALLING_ADDR 0x31
+#define FDL_FALLING_ADDR 0x32
+#define ELE0_TOUCH_THRESHOLD_ADDR 0x41
+#define ELE0_RELEASE_THRESHOLD_ADDR 0x42
+#define AFE_CONF_ADDR 0x5c
+#define FILTER_CONF_ADDR 0x5d
+
+/*
+ * ELECTRODE_CONF_ADDR: This register configures the number of
+ * enabled capacitance sensing inputs and its run/suspend mode.
+ */
+#define ELECTRODE_CONF_ADDR 0x5e
+#define ELECTRODE_CONF_QUICK_CHARGE 0x80
+#define AUTO_CONFIG_CTRL_ADDR 0x7b
+#define AUTO_CONFIG_USL_ADDR 0x7d
+#define AUTO_CONFIG_LSL_ADDR 0x7e
+#define AUTO_CONFIG_TL_ADDR 0x7f
+
+/* Threshold of touch/release trigger */
+#define TOUCH_THRESHOLD 0x08
+#define RELEASE_THRESHOLD 0x05
+/* Masks for touch and release triggers */
+#define TOUCH_STATUS_MASK 0xfff
+/* MPR121 has 12 keys */
+#define MPR121_MAX_KEY_COUNT 12
+
+#define MPR121_MIN_POLL_INTERVAL 10
+#define MPR121_MAX_POLL_INTERVAL 200
+
+struct mpr121_touchkey {
+ struct i2c_client *client;
+ struct input_dev *input_dev;
+ unsigned int statusbits;
+ unsigned int keycount;
+ u32 keycodes[MPR121_MAX_KEY_COUNT];
+};
+
+struct mpr121_init_register {
+ int addr;
+ u8 val;
+};
+
+static const struct mpr121_init_register init_reg_table[] = {
+ { MHD_RISING_ADDR, 0x1 },
+ { NHD_RISING_ADDR, 0x1 },
+ { MHD_FALLING_ADDR, 0x1 },
+ { NHD_FALLING_ADDR, 0x1 },
+ { NCL_FALLING_ADDR, 0xff },
+ { FDL_FALLING_ADDR, 0x02 },
+ { FILTER_CONF_ADDR, 0x04 },
+ { AFE_CONF_ADDR, 0x0b },
+ { AUTO_CONFIG_CTRL_ADDR, 0x0b },
+};
+
+static void mpr121_vdd_supply_disable(void *data)
+{
+ struct regulator *vdd_supply = data;
+
+ regulator_disable(vdd_supply);
+}
+
+static struct regulator *mpr121_vdd_supply_init(struct device *dev)
+{
+ struct regulator *vdd_supply;
+ int err;
+
+ vdd_supply = devm_regulator_get(dev, "vdd");
+ if (IS_ERR(vdd_supply)) {
+ dev_err(dev, "failed to get vdd regulator: %ld\n",
+ PTR_ERR(vdd_supply));
+ return vdd_supply;
+ }
+
+ err = regulator_enable(vdd_supply);
+ if (err) {
+ dev_err(dev, "failed to enable vdd regulator: %d\n", err);
+ return ERR_PTR(err);
+ }
+
+ err = devm_add_action_or_reset(dev, mpr121_vdd_supply_disable,
+ vdd_supply);
+ if (err) {
+ dev_err(dev, "failed to add disable regulator action: %d\n",
+ err);
+ return ERR_PTR(err);
+ }
+
+ return vdd_supply;
+}
+
+static void mpr_touchkey_report(struct input_dev *dev)
+{
+ struct mpr121_touchkey *mpr121 = input_get_drvdata(dev);
+ struct input_dev *input = mpr121->input_dev;
+ struct i2c_client *client = mpr121->client;
+ unsigned long bit_changed;
+ unsigned int key_num;
+ int reg;
+
+ reg = i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_1_ADDR);
+ if (reg < 0) {
+ dev_err(&client->dev, "i2c read error [%d]\n", reg);
+ return;
+ }
+
+ reg <<= 8;
+ reg |= i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_0_ADDR);
+ if (reg < 0) {
+ dev_err(&client->dev, "i2c read error [%d]\n", reg);
+ return;
+ }
+
+ reg &= TOUCH_STATUS_MASK;
+ /* use old press bit to figure out which bit changed */
+ bit_changed = reg ^ mpr121->statusbits;
+ mpr121->statusbits = reg;
+ for_each_set_bit(key_num, &bit_changed, mpr121->keycount) {
+ unsigned int key_val, pressed;
+
+ pressed = reg & BIT(key_num);
+ key_val = mpr121->keycodes[key_num];
+
+ input_event(input, EV_MSC, MSC_SCAN, key_num);
+ input_report_key(input, key_val, pressed);
+
+ dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val,
+ pressed ? "pressed" : "released");
+
+ }
+ input_sync(input);
+}
+
+static irqreturn_t mpr_touchkey_interrupt(int irq, void *dev_id)
+{
+ struct mpr121_touchkey *mpr121 = dev_id;
+
+ mpr_touchkey_report(mpr121->input_dev);
+
+ return IRQ_HANDLED;
+}
+
+static int mpr121_phys_init(struct mpr121_touchkey *mpr121,
+ struct i2c_client *client, int vdd_uv)
+{
+ const struct mpr121_init_register *reg;
+ unsigned char usl, lsl, tl, eleconf;
+ int i, t, vdd, ret;
+
+ /* Set up touch/release threshold for ele0-ele11 */
+ for (i = 0; i <= MPR121_MAX_KEY_COUNT; i++) {
+ t = ELE0_TOUCH_THRESHOLD_ADDR + (i * 2);
+ ret = i2c_smbus_write_byte_data(client, t, TOUCH_THRESHOLD);
+ if (ret < 0)
+ goto err_i2c_write;
+ ret = i2c_smbus_write_byte_data(client, t + 1,
+ RELEASE_THRESHOLD);
+ if (ret < 0)
+ goto err_i2c_write;
+ }
+
+ /* Set up init register */
+ for (i = 0; i < ARRAY_SIZE(init_reg_table); i++) {
+ reg = &init_reg_table[i];
+ ret = i2c_smbus_write_byte_data(client, reg->addr, reg->val);
+ if (ret < 0)
+ goto err_i2c_write;
+ }
+
+
+ /*
+ * Capacitance on sensing input varies and needs to be compensated.
+ * The internal MPR121-auto-configuration can do this if it's
+ * registers are set properly (based on vdd_uv).
+ */
+ vdd = vdd_uv / 1000;
+ usl = ((vdd - 700) * 256) / vdd;
+ lsl = (usl * 65) / 100;
+ tl = (usl * 90) / 100;
+ ret = i2c_smbus_write_byte_data(client, AUTO_CONFIG_USL_ADDR, usl);
+ ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_LSL_ADDR, lsl);
+ ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_TL_ADDR, tl);
+
+ /*
+ * Quick charge bit will let the capacitive charge to ready
+ * state quickly, or the buttons may not function after system
+ * boot.
+ */
+ eleconf = mpr121->keycount | ELECTRODE_CONF_QUICK_CHARGE;
+ ret |= i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
+ eleconf);
+ if (ret != 0)
+ goto err_i2c_write;
+
+ dev_dbg(&client->dev, "set up with %x keys.\n", mpr121->keycount);
+
+ return 0;
+
+err_i2c_write:
+ dev_err(&client->dev, "i2c write error: %d\n", ret);
+ return ret;
+}
+
+static int mpr_touchkey_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct regulator *vdd_supply;
+ int vdd_uv;
+ struct mpr121_touchkey *mpr121;
+ struct input_dev *input_dev;
+ u32 poll_interval = 0;
+ int error;
+ int i;
+
+ vdd_supply = mpr121_vdd_supply_init(dev);
+ if (IS_ERR(vdd_supply))
+ return PTR_ERR(vdd_supply);
+
+ vdd_uv = regulator_get_voltage(vdd_supply);
+
+ mpr121 = devm_kzalloc(dev, sizeof(*mpr121), GFP_KERNEL);
+ if (!mpr121)
+ return -ENOMEM;
+
+ input_dev = devm_input_allocate_device(dev);
+ if (!input_dev)
+ return -ENOMEM;
+
+ mpr121->client = client;
+ mpr121->input_dev = input_dev;
+ mpr121->keycount = device_property_count_u32(dev, "linux,keycodes");
+ if (mpr121->keycount > MPR121_MAX_KEY_COUNT) {
+ dev_err(dev, "too many keys defined (%d)\n", mpr121->keycount);
+ return -EINVAL;
+ }
+
+ error = device_property_read_u32_array(dev, "linux,keycodes",
+ mpr121->keycodes,
+ mpr121->keycount);
+ if (error) {
+ dev_err(dev,
+ "failed to read linux,keycode property: %d\n", error);
+ return error;
+ }
+
+ input_dev->name = "Freescale MPR121 Touchkey";
+ input_dev->id.bustype = BUS_I2C;
+ input_dev->dev.parent = dev;
+ if (device_property_read_bool(dev, "autorepeat"))
+ __set_bit(EV_REP, input_dev->evbit);
+ input_set_capability(input_dev, EV_MSC, MSC_SCAN);
+ input_set_drvdata(input_dev, mpr121);
+
+ input_dev->keycode = mpr121->keycodes;
+ input_dev->keycodesize = sizeof(mpr121->keycodes[0]);
+ input_dev->keycodemax = mpr121->keycount;
+
+ for (i = 0; i < mpr121->keycount; i++)
+ input_set_capability(input_dev, EV_KEY, mpr121->keycodes[i]);
+
+ error = mpr121_phys_init(mpr121, client, vdd_uv);
+ if (error) {
+ dev_err(dev, "Failed to init register\n");
+ return error;
+ }
+
+ device_property_read_u32(dev, "poll-interval", &poll_interval);
+
+ if (client->irq) {
+ error = devm_request_threaded_irq(dev, client->irq, NULL,
+ mpr_touchkey_interrupt,
+ IRQF_TRIGGER_FALLING |
+ IRQF_ONESHOT,
+ dev->driver->name, mpr121);
+ if (error) {
+ dev_err(dev, "Failed to register interrupt\n");
+ return error;
+ }
+ } else if (poll_interval) {
+ if (poll_interval < MPR121_MIN_POLL_INTERVAL)
+ return -EINVAL;
+
+ if (poll_interval > MPR121_MAX_POLL_INTERVAL)
+ return -EINVAL;
+
+ error = input_setup_polling(input_dev, mpr_touchkey_report);
+ if (error) {
+ dev_err(dev, "Failed to setup polling\n");
+ return error;
+ }
+
+ input_set_poll_interval(input_dev, poll_interval);
+ input_set_min_poll_interval(input_dev,
+ MPR121_MIN_POLL_INTERVAL);
+ input_set_max_poll_interval(input_dev,
+ MPR121_MAX_POLL_INTERVAL);
+ } else {
+ dev_err(dev,
+ "invalid IRQ number and polling not configured\n");
+ return -EINVAL;
+ }
+
+ error = input_register_device(input_dev);
+ if (error)
+ return error;
+
+ i2c_set_clientdata(client, mpr121);
+ device_init_wakeup(dev,
+ device_property_read_bool(dev, "wakeup-source"));
+
+ return 0;
+}
+
+static int __maybe_unused mpr_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(client->irq);
+
+ i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR, 0x00);
+
+ return 0;
+}
+
+static int __maybe_unused mpr_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);
+
+ if (device_may_wakeup(&client->dev))
+ disable_irq_wake(client->irq);
+
+ i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
+ mpr121->keycount);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(mpr121_touchkey_pm_ops, mpr_suspend, mpr_resume);
+
+static const struct i2c_device_id mpr121_id[] = {
+ { "mpr121_touchkey", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, mpr121_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id mpr121_touchkey_dt_match_table[] = {
+ { .compatible = "fsl,mpr121-touchkey" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, mpr121_touchkey_dt_match_table);
+#endif
+
+static struct i2c_driver mpr_touchkey_driver = {
+ .driver = {
+ .name = "mpr121",
+ .pm = &mpr121_touchkey_pm_ops,
+ .of_match_table = of_match_ptr(mpr121_touchkey_dt_match_table),
+ },
+ .id_table = mpr121_id,
+ .probe = mpr_touchkey_probe,
+};
+
+module_i2c_driver(mpr_touchkey_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
+MODULE_DESCRIPTION("Touch Key driver for Freescale MPR121 Chip");