| Message ID | 20240526212443.8496-2-kuzhylol@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v3,1/2] dt-bindings: input: touchscreen: add Hynitron CST816X | expand |
Hi Oleh, On Sun, May 26, 2024 at 11:24:42PM +0200, Oleh Kuzhylnyi wrote: > Introduce support for the Hynitron CST816X touchscreen controller > used for 240×240 1.28-inch Round LCD Display Module manufactured > by Waveshare Electronics. The driver is designed based on an Arduino > implementation marked as under MIT License. This driver is written > for a particular round display based on the CST816S controller, which > is not compatiable with existing driver for Hynitron controllers. > > Signed-off-by: Oleh Kuzhylnyi <kuzhylol@gmail.com> > --- > > Changes in v3: > - Drop timer and delayed work > - Process touch in threaded IRQ context > - Fix chip reset sequence > - Move input_register() before devm_request_threaded_irq() > - Re-arrange and document input reporting > - Set u16 data type for event_code > - Remove double tap event to prevent continuous double side sliding > > drivers/input/touchscreen/Kconfig | 12 + > drivers/input/touchscreen/Makefile | 1 + > drivers/input/touchscreen/hynitron-cst816x.c | 257 +++++++++++++++++++ > 3 files changed, 270 insertions(+) > create mode 100644 drivers/input/touchscreen/hynitron-cst816x.c > > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig > index c821fe3ee794..02f40d0fbac0 100644 > --- a/drivers/input/touchscreen/Kconfig > +++ b/drivers/input/touchscreen/Kconfig > @@ -481,6 +481,18 @@ config TOUCHSCREEN_HYNITRON_CSTXXX > To compile this driver as a module, choose M here: the > module will be called hynitron-cstxxx. > > +config TOUCHSCREEN_HYNITRON_CST816X > + tristate "Hynitron CST816X touchscreen support" > + depends on I2C > + help > + Say Y here if you have a touchscreen using a Hynitron > + CST816X touchscreen controller. > + > + If unsure, say N. > + > + To compile this driver as a module, choose M here: the > + module will be called hynitron-cst816x. > + > config TOUCHSCREEN_ILI210X > tristate "Ilitek ILI210X based touchscreen" > depends on I2C > diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile > index a81cb5aa21a5..a92a87417a97 100644 > --- a/drivers/input/touchscreen/Makefile > +++ b/drivers/input/touchscreen/Makefile > @@ -51,6 +51,7 @@ obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_CORE) += goodix_berlin_core.o > obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_I2C) += goodix_berlin_i2c.o > obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_SPI) += goodix_berlin_spi.o > obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o > +obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CST816X) += hynitron-cst816x.o > obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CSTXXX) += hynitron_cstxxx.o > obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o > obj-$(CONFIG_TOUCHSCREEN_ILITEK) += ilitek_ts_i2c.o > diff --git a/drivers/input/touchscreen/hynitron-cst816x.c b/drivers/input/touchscreen/hynitron-cst816x.c > new file mode 100644 > index 000000000000..5bb85ec1d60e > --- /dev/null > +++ b/drivers/input/touchscreen/hynitron-cst816x.c > @@ -0,0 +1,257 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Driver for I2C connected Hynitron CST816X Touchscreen > + * > + * Copyright (C) 2024 Oleh Kuzhylnyi <kuzhylol@gmail.com> > + */ > +#include <linux/delay.h> > +#include <linux/err.h> > +#include <linux/gpio/consumer.h> > +#include <linux/i2c.h> > +#include <linux/input.h> > +#include <linux/interrupt.h> > +#include <linux/module.h> > + > +enum cst816x_registers { > + CST816X_FRAME = 0x01, > + CST816X_MOTION = 0xEC, > +}; > + > +enum cst816x_gestures { > + CST816X_SWIPE_UP = 0x01, > + CST816X_SWIPE_DOWN = 0x02, > + CST816X_SWIPE_LEFT = 0x03, > + CST816X_SWIPE_RIGHT = 0x04, > + CST816X_SINGLE_TAP = 0x05, > + CST816X_LONG_PRESS = 0x0C, > +}; > + > +struct cst816x_touch_info { > + u8 gesture; > + u8 touch; > + u8 abs_x; Is this the right size? You are doing: priv->info.abs_x = ((raw[2] & 0x0F) << 8) | raw[3]; Which suggests it should be u16? > + u8 abs_y; > +} __packed; Why does this need to be __packed? > + > +struct cst816x_priv { > + struct device *dev; > + struct i2c_client *client; > + struct gpio_desc *reset; > + struct input_dev *input; > + struct cst816x_touch_info info; Why do you need to have this here? It is tiny and does not need to be kept around, just use on stack variable. > + > + u8 rxtx[8]; > +}; > + > +struct cst816x_event_mapping { > + enum cst816x_gestures gesture; > + u16 event_code; > +}; > + > +static const struct cst816x_event_mapping cst816x_event_map[] = { > + {CST816X_SWIPE_UP, BTN_FORWARD}, > + {CST816X_SWIPE_DOWN, BTN_BACK}, > + {CST816X_SWIPE_LEFT, BTN_LEFT}, > + {CST816X_SWIPE_RIGHT, BTN_RIGHT}, > + {CST816X_SINGLE_TAP, BTN_TOUCH}, > + {CST816X_LONG_PRESS, BTN_TOOL_TRIPLETAP} > +}; > + > +static int cst816x_i2c_read_register(struct cst816x_priv *priv, u8 reg) Maybe supply buffer and size as arguments? > +{ > + struct i2c_client *client; > + struct i2c_msg xfer[2]; > + int rc; > + > + client = priv->client; > + > + xfer[0].addr = client->addr; > + xfer[0].flags = 0; > + xfer[0].len = sizeof(reg); > + xfer[0].buf = ® > + > + xfer[1].addr = client->addr; > + xfer[1].flags = I2C_M_RD; > + xfer[1].len = sizeof(priv->rxtx); > + xfer[1].buf = priv->rxtx; > + > + rc = i2c_transfer(client->adapter, xfer, ARRAY_SIZE(xfer)); > + if (rc != ARRAY_SIZE(xfer)) { error = rc >= 0 ? -EIO : rc; dev_err(...); return error; } return 0; > + if (rc >= 0) > + rc = -EIO; > + } else { > + rc = 0; > + } > + > + if (rc < 0) > + dev_err(&client->dev, "i2c rx err: %d\n", rc); > + > + return rc; > +} > + > +static int cst816x_process_touch(struct cst816x_priv *priv) > +{ > + u8 *raw; > + int rc; > + > + rc = cst816x_i2c_read_register(priv, CST816X_FRAME); > + if (!rc) { > + raw = priv->rxtx; > + > + priv->info.gesture = raw[0]; > + priv->info.touch = raw[1]; > + priv->info.abs_x = ((raw[2] & 0x0F) << 8) | raw[3]; > + priv->info.abs_y = ((raw[4] & 0x0F) << 8) | raw[5]; > + > + dev_dbg(priv->dev, "x: %d, y: %d, t: %d, g: 0x%x\n", > + priv->info.abs_x, priv->info.abs_y, priv->info.touch, > + priv->info.gesture); > + } > + > + return rc; > +} > + > +static int cst816x_register_input(struct cst816x_priv *priv) > +{ > + priv->input = devm_input_allocate_device(priv->dev); > + if (!priv->input) > + return -ENOMEM; > + > + priv->input->name = "Hynitron CST816X Touchscreen"; > + priv->input->phys = "input/ts"; > + priv->input->id.bustype = BUS_I2C; > + input_set_drvdata(priv->input, priv); > + > + for (unsigned int i = 0; i < ARRAY_SIZE(cst816x_event_map); i++) { > + input_set_capability(priv->input, EV_KEY, > + cst816x_event_map[i].event_code); > + } > + > + input_set_abs_params(priv->input, ABS_X, 0, 240, 0, 0); > + input_set_abs_params(priv->input, ABS_Y, 0, 240, 0, 0); > + > + return input_register_device(priv->input); > +} > + > +static void cst816x_reset(struct cst816x_priv *priv) > +{ > + gpiod_set_value_cansleep(priv->reset, 1); > + msleep(50); > + gpiod_set_value_cansleep(priv->reset, 0); > + msleep(100); > +} > + > +static void report_gesture_event(const struct cst816x_priv *priv, > + enum cst816x_gestures gesture, bool touch) > +{ > + for (unsigned int i = 0; i < ARRAY_SIZE(cst816x_event_map); i++) { > + if (cst816x_event_map[i].gesture == gesture) { > + input_report_key(priv->input, > + cst816x_event_map[i].event_code, > + touch); If you make cst816x_event_map an array of 16 entries with unised positions mapped to KEY_RESERVED you can do: key = cst816x_event_map[raw[0] & 0x0f]; if (key != KEY_RESERVED) input_report_key(priv->input, key, touch); and you do not need to loop. Thanks.
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index c821fe3ee794..02f40d0fbac0 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -481,6 +481,18 @@ config TOUCHSCREEN_HYNITRON_CSTXXX To compile this driver as a module, choose M here: the module will be called hynitron-cstxxx. +config TOUCHSCREEN_HYNITRON_CST816X + tristate "Hynitron CST816X touchscreen support" + depends on I2C + help + Say Y here if you have a touchscreen using a Hynitron + CST816X touchscreen controller. + + If unsure, say N. + + To compile this driver as a module, choose M here: the + module will be called hynitron-cst816x. + config TOUCHSCREEN_ILI210X tristate "Ilitek ILI210X based touchscreen" depends on I2C diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index a81cb5aa21a5..a92a87417a97 100644 --- a/drivers/input/touchscreen/Makefile +++ b/drivers/input/touchscreen/Makefile @@ -51,6 +51,7 @@ obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_CORE) += goodix_berlin_core.o obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_I2C) += goodix_berlin_i2c.o obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_SPI) += goodix_berlin_spi.o obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o +obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CST816X) += hynitron-cst816x.o obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CSTXXX) += hynitron_cstxxx.o obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o obj-$(CONFIG_TOUCHSCREEN_ILITEK) += ilitek_ts_i2c.o diff --git a/drivers/input/touchscreen/hynitron-cst816x.c b/drivers/input/touchscreen/hynitron-cst816x.c new file mode 100644 index 000000000000..5bb85ec1d60e --- /dev/null +++ b/drivers/input/touchscreen/hynitron-cst816x.c @@ -0,0 +1,257 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for I2C connected Hynitron CST816X Touchscreen + * + * Copyright (C) 2024 Oleh Kuzhylnyi <kuzhylol@gmail.com> + */ +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/interrupt.h> +#include <linux/module.h> + +enum cst816x_registers { + CST816X_FRAME = 0x01, + CST816X_MOTION = 0xEC, +}; + +enum cst816x_gestures { + CST816X_SWIPE_UP = 0x01, + CST816X_SWIPE_DOWN = 0x02, + CST816X_SWIPE_LEFT = 0x03, + CST816X_SWIPE_RIGHT = 0x04, + CST816X_SINGLE_TAP = 0x05, + CST816X_LONG_PRESS = 0x0C, +}; + +struct cst816x_touch_info { + u8 gesture; + u8 touch; + u8 abs_x; + u8 abs_y; +} __packed; + +struct cst816x_priv { + struct device *dev; + struct i2c_client *client; + struct gpio_desc *reset; + struct input_dev *input; + struct cst816x_touch_info info; + + u8 rxtx[8]; +}; + +struct cst816x_event_mapping { + enum cst816x_gestures gesture; + u16 event_code; +}; + +static const struct cst816x_event_mapping cst816x_event_map[] = { + {CST816X_SWIPE_UP, BTN_FORWARD}, + {CST816X_SWIPE_DOWN, BTN_BACK}, + {CST816X_SWIPE_LEFT, BTN_LEFT}, + {CST816X_SWIPE_RIGHT, BTN_RIGHT}, + {CST816X_SINGLE_TAP, BTN_TOUCH}, + {CST816X_LONG_PRESS, BTN_TOOL_TRIPLETAP} +}; + +static int cst816x_i2c_read_register(struct cst816x_priv *priv, u8 reg) +{ + struct i2c_client *client; + struct i2c_msg xfer[2]; + int rc; + + client = priv->client; + + xfer[0].addr = client->addr; + xfer[0].flags = 0; + xfer[0].len = sizeof(reg); + xfer[0].buf = ® + + xfer[1].addr = client->addr; + xfer[1].flags = I2C_M_RD; + xfer[1].len = sizeof(priv->rxtx); + xfer[1].buf = priv->rxtx; + + rc = i2c_transfer(client->adapter, xfer, ARRAY_SIZE(xfer)); + if (rc != ARRAY_SIZE(xfer)) { + if (rc >= 0) + rc = -EIO; + } else { + rc = 0; + } + + if (rc < 0) + dev_err(&client->dev, "i2c rx err: %d\n", rc); + + return rc; +} + +static int cst816x_process_touch(struct cst816x_priv *priv) +{ + u8 *raw; + int rc; + + rc = cst816x_i2c_read_register(priv, CST816X_FRAME); + if (!rc) { + raw = priv->rxtx; + + priv->info.gesture = raw[0]; + priv->info.touch = raw[1]; + priv->info.abs_x = ((raw[2] & 0x0F) << 8) | raw[3]; + priv->info.abs_y = ((raw[4] & 0x0F) << 8) | raw[5]; + + dev_dbg(priv->dev, "x: %d, y: %d, t: %d, g: 0x%x\n", + priv->info.abs_x, priv->info.abs_y, priv->info.touch, + priv->info.gesture); + } + + return rc; +} + +static int cst816x_register_input(struct cst816x_priv *priv) +{ + priv->input = devm_input_allocate_device(priv->dev); + if (!priv->input) + return -ENOMEM; + + priv->input->name = "Hynitron CST816X Touchscreen"; + priv->input->phys = "input/ts"; + priv->input->id.bustype = BUS_I2C; + input_set_drvdata(priv->input, priv); + + for (unsigned int i = 0; i < ARRAY_SIZE(cst816x_event_map); i++) { + input_set_capability(priv->input, EV_KEY, + cst816x_event_map[i].event_code); + } + + input_set_abs_params(priv->input, ABS_X, 0, 240, 0, 0); + input_set_abs_params(priv->input, ABS_Y, 0, 240, 0, 0); + + return input_register_device(priv->input); +} + +static void cst816x_reset(struct cst816x_priv *priv) +{ + gpiod_set_value_cansleep(priv->reset, 1); + msleep(50); + gpiod_set_value_cansleep(priv->reset, 0); + msleep(100); +} + +static void report_gesture_event(const struct cst816x_priv *priv, + enum cst816x_gestures gesture, bool touch) +{ + for (unsigned int i = 0; i < ARRAY_SIZE(cst816x_event_map); i++) { + if (cst816x_event_map[i].gesture == gesture) { + input_report_key(priv->input, + cst816x_event_map[i].event_code, + touch); + break; + } + } + + if (!touch) + input_report_key(priv->input, BTN_TOUCH, 0); +} + +/* + * Supports five gestures: TOUCH, LEFT, RIGHT, FORWARD, BACK, and LONG_PRESS. + * Reports surface interaction, sliding coordinates and finger detachment. + * + * 1. TOUCH Gesture Scenario: + * + * [x/y] [touch] [gesture] [Action] [Report ABS] [Report Key] + * x y true 0x00 Touch ABS_X_Y BTN_TOUCH + * x y true 0x00 Slide ABS_X_Y + * x y false 0x05 Gesture BTN_TOUCH + * + * 2. LEFT, RIGHT, FORWARD, BACK, and LONG_PRESS Gestures Scenario: + * + * [x/y] [touch] [gesture] [Action] [Report ABS] [Report Key] + * x y true 0x00 Touch ABS_X_Y BTN_TOUCH + * x y true 0x01 Gesture ABS_X_Y BTN_FORWARD + * x y true 0x01 Slide ABS_X_Y + * x y false 0x01 Detach BTN_FORWARD | BTN_TOUCH + */ +static irqreturn_t cst816x_irq_cb(int irq, void *cookie) +{ + struct cst816x_priv *priv = (struct cst816x_priv *)cookie; + + if (!cst816x_process_touch(priv)) { + if (priv->info.touch) { + input_report_abs(priv->input, ABS_X, priv->info.abs_x); + input_report_abs(priv->input, ABS_Y, priv->info.abs_y); + input_report_key(priv->input, BTN_TOUCH, 1); + } + + if (priv->info.gesture) + report_gesture_event(priv, priv->info.gesture, + priv->info.touch); + + input_sync(priv->input); + } + + return IRQ_HANDLED; +} + +static int cst816x_probe(struct i2c_client *client) +{ + struct cst816x_priv *priv; + struct device *dev = &client->dev; + int rc; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + priv->client = client; + + priv->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(priv->reset)) + return dev_err_probe(dev, PTR_ERR(priv->reset), + "reset gpio not found\n"); + + cst816x_reset(priv); + + rc = cst816x_register_input(priv); + if (rc) + return dev_err_probe(dev, rc, "input register failed\n"); + + rc = devm_request_threaded_irq(dev, client->irq, NULL, cst816x_irq_cb, + IRQF_ONESHOT, dev->driver->name, priv); + if (rc) + return dev_err_probe(dev, rc, "irq request failed\n"); + + return 0; +} + +static const struct i2c_device_id cst816x_id[] = { + { .name = "cst816s", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, cst816x_id); + +static const struct of_device_id cst816x_of_match[] = { + { .compatible = "hynitron,cst816s", }, + { } +}; +MODULE_DEVICE_TABLE(of, cst816x_of_match); + +static struct i2c_driver cst816x_driver = { + .driver = { + .name = "cst816x", + .of_match_table = cst816x_of_match, + }, + .id_table = cst816x_id, + .probe = cst816x_probe, +}; + +module_i2c_driver(cst816x_driver); + +MODULE_AUTHOR("Oleh Kuzhylnyi <kuzhylol@gmail.com>"); +MODULE_DESCRIPTION("Hynitron CST816X Touchscreen Driver"); +MODULE_LICENSE("GPL");
Introduce support for the Hynitron CST816X touchscreen controller used for 240×240 1.28-inch Round LCD Display Module manufactured by Waveshare Electronics. The driver is designed based on an Arduino implementation marked as under MIT License. This driver is written for a particular round display based on the CST816S controller, which is not compatiable with existing driver for Hynitron controllers. Signed-off-by: Oleh Kuzhylnyi <kuzhylol@gmail.com> --- Changes in v3: - Drop timer and delayed work - Process touch in threaded IRQ context - Fix chip reset sequence - Move input_register() before devm_request_threaded_irq() - Re-arrange and document input reporting - Set u16 data type for event_code - Remove double tap event to prevent continuous double side sliding drivers/input/touchscreen/Kconfig | 12 + drivers/input/touchscreen/Makefile | 1 + drivers/input/touchscreen/hynitron-cst816x.c | 257 +++++++++++++++++++ 3 files changed, 270 insertions(+) create mode 100644 drivers/input/touchscreen/hynitron-cst816x.c