On Wed, May 18, 2016 at 2:59 PM, Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote: > On Tue, May 17, 2016 at 12:29:32PM -0700, Grant Grundler wrote: >> From: Daniel Hung-yu Wu <hywu@xxxxxxxxxx> >> >> Add I2C driver for Atmel Capacitive Touch Button device. >> >> Signed-off-by: Hung-yu Wu <hywu@xxxxxxxxxx> >> Signed-off-by: Grant Grundler <grundler@xxxxxxxxxxxx> > > Applied, thank you. Awesome! Thanks for your help Dmitry! :) grant > >> --- >> drivers/input/misc/Kconfig | 13 ++ >> drivers/input/misc/Makefile | 1 + >> drivers/input/misc/atmel_captouch.c | 287 ++++++++++++++++++++++++++++++++++++ >> 3 files changed, 299 insertions(+) >> create mode 100644 drivers/input/misc/atmel_captouch.c >> >> V4: wordsmithing comments at top of file. >> Added missing semicolon to CONFIG_OF data struct. >> >> V3: use dash, not underscore in nodename. Wordsmith Kconfig help text. >> >> V2: split Documentation/devicetree/bindings from driver patch. >> rename "atmel,atmegaxx_captouch" to "atmel,captouch" since it's irrelevant >> which controller implements the register set/controller. >> >> V1: posted https://lkml.org/lkml/2016/5/3/613 >> >> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig >> index 838824b..d8b6620 100644 >> --- a/drivers/input/misc/Kconfig >> +++ b/drivers/input/misc/Kconfig >> @@ -82,6 +82,19 @@ config INPUT_ARIZONA_HAPTICS >> To compile this driver as a module, choose M here: the >> module will be called arizona-haptics. >> >> +config INPUT_ATMEL_CAPTOUCH >> + tristate "Atmel Capacitive Touch Button Driver" >> + depends on OF || COMPILE_TEST >> + help >> + Say Y here if an Atmel Capacitive Touch Button device which >> + implements "captouch" protocol is connected to I2C bus. Typically >> + this device consists of Atmel Touch sensor controlled by AtMegaXX >> + MCU running firmware based on Qtouch library. >> + One should find "atmel,captouch" node in the board specific DTS. >> + >> + To compile this driver as a module, choose M here: the >> + module will be called atmel_captouch. >> + >> config INPUT_BMA150 >> tristate "BMA150/SMB380 acceleration sensor support" >> depends on I2C >> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile >> index f77268e..b5ec626 100644 >> --- a/drivers/input/misc/Makefile >> +++ b/drivers/input/misc/Makefile >> @@ -17,6 +17,7 @@ obj-$(CONFIG_INPUT_APANEL) += apanel.o >> obj-$(CONFIG_INPUT_ARIZONA_HAPTICS) += arizona-haptics.o >> obj-$(CONFIG_INPUT_ATI_REMOTE2) += ati_remote2.o >> obj-$(CONFIG_INPUT_ATLAS_BTNS) += atlas_btns.o >> +obj-$(CONFIG_INPUT_ATMEL_CAPTOUCH) += atmel_captouch.o >> obj-$(CONFIG_INPUT_BFIN_ROTARY) += bfin_rotary.o >> obj-$(CONFIG_INPUT_BMA150) += bma150.o >> obj-$(CONFIG_INPUT_CM109) += cm109.o >> diff --git a/drivers/input/misc/atmel_captouch.c b/drivers/input/misc/atmel_captouch.c >> new file mode 100644 >> index 0000000..91bfc73 >> --- /dev/null >> +++ b/drivers/input/misc/atmel_captouch.c >> @@ -0,0 +1,287 @@ >> +/* >> + * Atmel Capacitive Touch Button Driver >> + * >> + * Copyright (C) 2016 Google, inc. >> + * >> + * This software is licensed under the terms of the GNU General Public >> + * License version 2, as published by the Free Software Foundation, and >> + * may be copied, distributed, and modified under those terms. >> + * >> + * This program is distributed in the hope that it will be useful, >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >> + * GNU General Public License for more details. >> + */ >> + >> +/* >> + * It's irrelevant the HW used to develop captouch driver is based >> + * on Atmega88PA part and uses QtouchADC parts for sensing touch. >> + * Calling this driver "captouch" is an arbitrary way to distinguish >> + * the protocol this driver supports from other atmel/qtouch drivers. >> + * >> + * captouch driver supports a newer/different version of the I2C >> + * registers/commands than the qt1070.c driver. >> + * Don't let the similarity of the general driver structure fool you. :) >> + * >> + * For raw i2c access from userspace, use i2cset/i2cget >> + * to poke at /dev/i2c-N devices. >> + */ >> + >> +#include <linux/device.h> >> +#include <linux/kernel.h> >> +#include <linux/module.h> >> +#include <linux/init.h> >> +#include <linux/i2c.h> >> +#include <linux/input.h> >> +#include <linux/interrupt.h> >> +#include <linux/slab.h> >> + >> +/* Maximum number of buttons supported */ >> +#define MAX_NUM_OF_BUTTONS 8 >> + >> +/* Registers */ >> +#define REG_KEY1_THRESHOLD 0x02 >> +#define REG_KEY2_THRESHOLD 0x03 >> +#define REG_KEY3_THRESHOLD 0x04 >> +#define REG_KEY4_THRESHOLD 0x05 >> + >> +#define REG_KEY1_REF_H 0x20 >> +#define REG_KEY1_REF_L 0x21 >> +#define REG_KEY2_REF_H 0x22 >> +#define REG_KEY2_REF_L 0x23 >> +#define REG_KEY3_REF_H 0x24 >> +#define REG_KEY3_REF_L 0x25 >> +#define REG_KEY4_REF_H 0x26 >> +#define REG_KEY4_REF_L 0x27 >> + >> +#define REG_KEY1_DLT_H 0x30 >> +#define REG_KEY1_DLT_L 0x31 >> +#define REG_KEY2_DLT_H 0x32 >> +#define REG_KEY2_DLT_L 0x33 >> +#define REG_KEY3_DLT_H 0x34 >> +#define REG_KEY3_DLT_L 0x35 >> +#define REG_KEY4_DLT_H 0x36 >> +#define REG_KEY4_DLT_L 0x37 >> + >> +#define REG_KEY_STATE 0x3C >> + >> +/* >> + * @i2c_client: I2C slave device client pointer >> + * @input: Input device pointer >> + * @num_btn: Number of buttons >> + * @keycodes: map of button# to KeyCode >> + * @prev_btn: Previous key state to detect button "press" or "release" >> + * @xfer_buf: I2C transfer buffer >> + */ >> +struct atmel_captouch_device { >> + struct i2c_client *client; >> + struct input_dev *input; >> + u32 num_btn; >> + u32 keycodes[MAX_NUM_OF_BUTTONS]; >> + u8 prev_btn; >> + u8 xfer_buf[8] ____cacheline_aligned; >> +}; >> + >> +/* >> + * Read from I2C slave device >> + * The protocol is that the client has to provide both the register address >> + * and the length, and while reading back the device would prepend the data >> + * with address and length for verification. >> + */ >> +static int atmel_read(struct atmel_captouch_device *capdev, >> + u8 reg, u8 *data, size_t len) >> +{ >> + struct i2c_client *client = capdev->client; >> + struct device *dev = &client->dev; >> + struct i2c_msg msg[2]; >> + int err; >> + >> + if (len > sizeof(capdev->xfer_buf) - 2) >> + return -EINVAL; >> + >> + capdev->xfer_buf[0] = reg; >> + capdev->xfer_buf[1] = len; >> + >> + msg[0].addr = client->addr; >> + msg[0].flags = 0; >> + msg[0].buf = capdev->xfer_buf; >> + msg[0].len = 2; >> + >> + msg[1].addr = client->addr; >> + msg[1].flags = I2C_M_RD; >> + msg[1].buf = capdev->xfer_buf; >> + msg[1].len = len + 2; >> + >> + err = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); >> + if (err != ARRAY_SIZE(msg)) >> + return err < 0 ? err : -EIO; >> + >> + if (capdev->xfer_buf[0] != reg) { >> + dev_err(dev, "I2C read error: register address does not match\n"); >> + return -ECOMM; >> + } >> + >> + memcpy(data, &capdev->xfer_buf[2], len); >> + >> + return 0; >> +} >> + >> +/* >> + * Handle interrupt and report the key changes to the input system. >> + * Multi-touch can be supported; however, it really depends on whether >> + * the device can multi-touch. >> + */ >> +static irqreturn_t atmel_captouch_isr(int irq, void *data) >> +{ >> + struct atmel_captouch_device *capdev = data; >> + struct device *dev = &capdev->client->dev; >> + int error; >> + int i; >> + u8 new_btn; >> + u8 changed_btn; >> + >> + error = atmel_read(capdev, REG_KEY_STATE, &new_btn, 1); >> + if (error) { >> + dev_err(dev, "failed to read button state: %d\n", error); >> + goto out; >> + } >> + >> + dev_dbg(dev, "%s: button state %#02x\n", __func__, new_btn); >> + >> + changed_btn = new_btn ^ capdev->prev_btn; >> + capdev->prev_btn = new_btn; >> + >> + for (i = 0; i < capdev->num_btn; i++) { >> + if (changed_btn & BIT(i)) >> + input_report_key(capdev->input, >> + capdev->keycodes[i], >> + new_btn & BIT(i)); >> + } >> + >> + input_sync(capdev->input); >> + >> +out: >> + return IRQ_HANDLED; >> +} >> + >> +/* >> + * Probe function to setup the device, input system and interrupt >> + */ >> +static int atmel_captouch_probe(struct i2c_client *client, >> + const struct i2c_device_id *id) >> +{ >> + struct atmel_captouch_device *capdev; >> + struct device *dev = &client->dev; >> + struct device_node *node; >> + int i; >> + int err; >> + >> + if (!i2c_check_functionality(client->adapter, >> + I2C_FUNC_SMBUS_BYTE_DATA | >> + I2C_FUNC_SMBUS_WORD_DATA | >> + I2C_FUNC_SMBUS_I2C_BLOCK)) { >> + dev_err(dev, "needed i2c functionality is not supported\n"); >> + return -EINVAL; >> + } >> + >> + capdev = devm_kzalloc(dev, sizeof(*capdev), GFP_KERNEL); >> + if (!capdev) >> + return -ENOMEM; >> + >> + capdev->client = client; >> + i2c_set_clientdata(client, capdev); >> + >> + err = atmel_read(capdev, REG_KEY_STATE, >> + &capdev->prev_btn, sizeof(capdev->prev_btn)); >> + if (err) { >> + dev_err(dev, "failed to read initial button state: %d\n", err); >> + return err; >> + } >> + >> + capdev->input = devm_input_allocate_device(dev); >> + if (!capdev->input) { >> + dev_err(dev, "failed to allocate input device\n"); >> + return -ENOMEM; >> + } >> + >> + capdev->input->id.bustype = BUS_I2C; >> + capdev->input->id.product = 0x880A; >> + capdev->input->id.version = 0; >> + capdev->input->name = "ATMegaXX Capacitive Button Controller"; >> + __set_bit(EV_KEY, capdev->input->evbit); >> + >> + node = dev->of_node; >> + if (!node) { >> + dev_err(dev, "failed to find matching node in device tree\n"); >> + return -EINVAL; >> + } >> + >> + if (of_property_read_bool(node, "autorepeat")) >> + __set_bit(EV_REP, capdev->input->evbit); >> + >> + capdev->num_btn = of_property_count_u32_elems(node, "linux,keymap"); >> + if (capdev->num_btn > MAX_NUM_OF_BUTTONS) >> + capdev->num_btn = MAX_NUM_OF_BUTTONS; >> + >> + err = of_property_read_u32_array(node, "linux,keycodes", >> + capdev->keycodes, >> + capdev->num_btn); >> + if (err) { >> + dev_err(dev, >> + "failed to read linux,keycode property: %d\n", err); >> + return err; >> + } >> + >> + for (i = 0; i < capdev->num_btn; i++) >> + __set_bit(capdev->keycodes[i], capdev->input->keybit); >> + >> + capdev->input->keycode = capdev->keycodes; >> + capdev->input->keycodesize = sizeof(capdev->keycodes[0]); >> + capdev->input->keycodemax = capdev->num_btn; >> + >> + err = input_register_device(capdev->input); >> + if (err) >> + return err; >> + >> + err = devm_request_threaded_irq(dev, client->irq, NULL, >> + atmel_captouch_isr, IRQF_ONESHOT, >> + "atmel_captouch", capdev); >> + if (err) { >> + dev_err(dev, "failed to request irq %d: %d\n", >> + client->irq, err); >> + return err; >> + } >> + >> + return 0; >> +} >> + >> +#ifdef CONFIG_OF >> +static const struct of_device_id atmel_captouch_of_id[] = { >> + { >> + .compatible = "atmel,captouch", >> + }, >> + { /* sentinel */ } >> +}; >> +MODULE_DEVICE_TABLE(of, atmel_captouch_of_id); >> +#endif >> + >> +static const struct i2c_device_id atmel_captouch_id[] = { >> + { "atmel_captouch", 0 }, >> + { } >> +}; >> +MODULE_DEVICE_TABLE(i2c, atmel_captouch_id); >> + >> +static struct i2c_driver atmel_captouch_driver = { >> + .probe = atmel_captouch_probe, >> + .id_table = atmel_captouch_id, >> + .driver = { >> + .name = "atmel_captouch", >> + .of_match_table = of_match_ptr(atmel_captouch_of_id), >> + }, >> +}; >> +module_i2c_driver(atmel_captouch_driver); >> + >> +/* Module information */ >> +MODULE_AUTHOR("Hung-yu Wu <hywu@xxxxxxxxxx>"); >> +MODULE_DESCRIPTION("Atmel ATmegaXX Capacitance Touch Sensor I2C Driver"); >> +MODULE_LICENSE("GPL v2"); >> -- >> 2.1.2 >> > > -- > Dmitry -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
