| Message ID | 20230415020222.216232-3-joelselvaraj.oss@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add support for Focaltech FTS Touchscreen | expand |
Le 15/04/2023 à 04:02, Joel Selvaraj a écrit : > The Focaltech FTS driver supports several variants of focaltech > touchscreens found in ~2018 era smartphones including variants found on > the PocoPhone F1 and the SHIFT6mq which are already present in mainline. > This driver is loosely based on the original driver from Focaltech > but has been simplified and largely reworked. > > Co-developed-by: Caleb Connolly <caleb-u60PMpPBjd35c1cvEZuMuQ@public.gmane.org> > Signed-off-by: Caleb Connolly <caleb-u60PMpPBjd35c1cvEZuMuQ@public.gmane.org> > Signed-off-by: Joel Selvaraj <joelselvaraj.oss-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> > --- > MAINTAINERS | 8 + > drivers/input/touchscreen/Kconfig | 12 + > drivers/input/touchscreen/Makefile | 1 + > drivers/input/touchscreen/focaltech_fts5452.c | 432 ++++++++++++++++++ > 4 files changed, 453 insertions(+) > create mode 100644 drivers/input/touchscreen/focaltech_fts5452.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 7ec4ce64f66d..1a3ea61e1f52 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -8028,6 +8028,14 @@ L: linux-input-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > S: Maintained > F: drivers/input/joystick/fsia6b.c > > +FOCALTECH FTS5452 TOUCHSCREEN DRIVER > +M: Joel Selvaraj <joelselvaraj.oss-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> > +M: Caleb Connolly <caleb-u60PMpPBjd35c1cvEZuMuQ@public.gmane.org> > +L: linux-input-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > +S: Maintained > +F: Documentation/devicetree/bindings/input/touchscreen/focaltech,fts5452.yaml > +F: drivers/input/touchscreen/focaltech_fts5452.c > + > FOCUSRITE SCARLETT GEN 2/3 MIXER DRIVER > M: Geoffrey D. Bennett <g@b4.vu> > L: alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org (moderated for non-subscribers) > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig > index 1feecd7ed3cb..11af91504969 100644 > --- a/drivers/input/touchscreen/Kconfig > +++ b/drivers/input/touchscreen/Kconfig > @@ -388,6 +388,18 @@ config TOUCHSCREEN_EXC3000 > To compile this driver as a module, choose M here: the > module will be called exc3000. > > +config TOUCHSCREEN_FOCALTECH_FTS5452 > + tristate "Focaltech FTS Touchscreen" > + depends on I2C > + help > + Say Y here to enable support for I2C connected Focaltech FTS > + based touch panels, including the 5452 and 8917 panels. > + > + If unsure, say N. > + > + To compile this driver as a module, choose M here: the > + module will be called focaltech_fts. focaltech_fts5452? Or should modifications be done elsewhere so that is does not look too 5452 specific? > + > config TOUCHSCREEN_FUJITSU > tristate "Fujitsu serial touchscreen" > select SERIO [...] > +struct fts_i2c_chip_data { > + int max_touch_points; > +}; > + > +int fts_check_status(struct fts_ts_data *data) > +{ > + int error, i = 0, count = 0; No need to init "i". > + unsigned int val, id; > + > + do { > + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_L, &id); > + if (error) > + dev_err(&data->client->dev, "I2C read failed: %d\n", error); > + > + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_H, &val); > + if (error) > + dev_err(&data->client->dev, "I2C read failed: %d\n", error); > + > + id |= val << 8; > + > + for (i = 0; i < ARRAY_SIZE(fts_chip_types); i++) > + if (id == fts_chip_types[i]) > + return 0; > + > + count++; > + msleep(FTS_INTERVAL_READ_REG_MS); > + } while ((count * FTS_INTERVAL_READ_REG_MS) < FTS_TIMEOUT_READ_REG_MS); > + > + return -EIO; > +} > + > +static int fts_report_touch(struct fts_ts_data *data) > +{ > + struct input_dev *input_dev = data->input_dev; > + int base; > + unsigned int x, y, z, maj; > + u8 slot, type; > + int error, i = 0; No need to init "i". > + > + u8 *buf = data->point_buf; > + > + memset(buf, 0, data->point_buf_size); > + > + error = regmap_bulk_read(data->regmap, 0, buf, data->point_buf_size); > + if (error) { > + dev_err(&data->client->dev, "I2C read failed: %d\n", error); > + return error; > + } > + > + for (i = 0; i < data->max_touch_points; i++) { > + base = FTS_ONE_TOUCH_LEN * i; [...] > +static int fts_ts_probe(struct i2c_client *client) > +{ > + const struct i2c_device_id *id = i2c_client_get_device_id(client); > + const struct fts_i2c_chip_data *chip_data; > + struct fts_ts_data *data; > + int error = 0; > + > + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { > + dev_err(&client->dev, "I2C not supported"); > + return -ENODEV; > + } > + > + if (!client->irq) { > + dev_err(&client->dev, "No irq specified\n"); > + return -EINVAL; > + } > + > + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + chip_data = device_get_match_data(&client->dev); > + if (!chip_data) > + chip_data = (const struct fts_i2c_chip_data *)id->driver_data; > + if (!chip_data || !chip_data->max_touch_points) { > + dev_err(&client->dev, "invalid or missing chip data\n"); > + return -EINVAL; > + } > + if (chip_data->max_touch_points > FTS_MAX_POINTS_SUPPORT) { > + dev_err(&client->dev, > + "invalid chip data, max_touch_points should be less than or equal to %d\n", > + FTS_MAX_POINTS_SUPPORT); > + return -EINVAL; > + } > + data->max_touch_points = chip_data->max_touch_points; > + > + data->client = client; > + i2c_set_clientdata(client, data); > + > + data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH); > + if (IS_ERR(data->reset_gpio)) { > + error = PTR_ERR(data->reset_gpio); > + dev_err(&client->dev, "Failed to request reset gpio, error %d\n", error); > + return error; > + } > + > + data->regmap = devm_regmap_init_i2c(client, &fts_ts_i2c_regmap_config); > + if (IS_ERR(data->regmap)) { > + error = PTR_ERR(data->regmap); > + dev_err(&client->dev, "regmap allocation failed, error %d\n", error); > + return error; > + } > + > + /* > + * AVDD is the analog voltage supply (2.6V to 3.3V) > + * VDDIO is the digital voltage supply (1.8V) > + */ > + data->regulators[0].supply = "avdd"; > + data->regulators[1].supply = "vddio"; > + error = devm_regulator_bulk_get(&client->dev, ARRAY_SIZE(data->regulators), > + data->regulators); > + if (error) { > + dev_err(&client->dev, "Failed to get regulators %d\n", error); > + return error; > + } > + > + error = devm_add_action_or_reset(&client->dev, fts_power_off, data); > + if (error) { > + dev_err(&client->dev, "failed to install power off handler\n"); > + return error; > + } Is it really needed? This could lead to disable something that is not enabled. This looks harmless, but I wonder if it can occur? I don't know the pm and input_dev frameworks enough to figure it myself, so this question is just about curiousity. CJ > + > + error = devm_request_threaded_irq(&client->dev, client->irq, NULL, > + fts_ts_interrupt, IRQF_ONESHOT, > + client->name, data); > + if (error) { > + dev_err(&client->dev, "Failed to request IRQ: %d\n", error); > + return error; > + } > + > + error = fts_input_init(data); > + if (error) > + return error; > + > + return 0; > +} [...]
Hi Joel, Great work so far! It's coming along nicely. Please find my latest feedback below. On Fri, Apr 14, 2023 at 09:02:19PM -0500, Joel Selvaraj wrote: > The Focaltech FTS driver supports several variants of focaltech > touchscreens found in ~2018 era smartphones including variants found on > the PocoPhone F1 and the SHIFT6mq which are already present in mainline. > This driver is loosely based on the original driver from Focaltech > but has been simplified and largely reworked. > > Co-developed-by: Caleb Connolly <caleb@connolly.tech> > Signed-off-by: Caleb Connolly <caleb@connolly.tech> > Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com> > --- > MAINTAINERS | 8 + > drivers/input/touchscreen/Kconfig | 12 + > drivers/input/touchscreen/Makefile | 1 + > drivers/input/touchscreen/focaltech_fts5452.c | 432 ++++++++++++++++++ > 4 files changed, 453 insertions(+) > create mode 100644 drivers/input/touchscreen/focaltech_fts5452.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 7ec4ce64f66d..1a3ea61e1f52 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -8028,6 +8028,14 @@ L: linux-input@vger.kernel.org > S: Maintained > F: drivers/input/joystick/fsia6b.c > > +FOCALTECH FTS5452 TOUCHSCREEN DRIVER > +M: Joel Selvaraj <joelselvaraj.oss@gmail.com> > +M: Caleb Connolly <caleb@connolly.tech> > +L: linux-input@vger.kernel.org > +S: Maintained > +F: Documentation/devicetree/bindings/input/touchscreen/focaltech,fts5452.yaml > +F: drivers/input/touchscreen/focaltech_fts5452.c > + > FOCUSRITE SCARLETT GEN 2/3 MIXER DRIVER > M: Geoffrey D. Bennett <g@b4.vu> > L: alsa-devel@alsa-project.org (moderated for non-subscribers) > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig > index 1feecd7ed3cb..11af91504969 100644 > --- a/drivers/input/touchscreen/Kconfig > +++ b/drivers/input/touchscreen/Kconfig > @@ -388,6 +388,18 @@ config TOUCHSCREEN_EXC3000 > To compile this driver as a module, choose M here: the > module will be called exc3000. > > +config TOUCHSCREEN_FOCALTECH_FTS5452 > + tristate "Focaltech FTS Touchscreen" > + depends on I2C > + help > + Say Y here to enable support for I2C connected Focaltech FTS > + based touch panels, including the 5452 and 8917 panels. This language is a bit misleading, as it seems to suggest three or more models are supported. It seems the title should simply be "FocalTech FTS5452 touchscreen controller" with the description as "...FocalTech FTS5452 and compatible touchscreen controllers." As more are found to be compatible (e.g. FTS8917), the compatible strings can simply be appended. > + > + If unsure, say N. > + > + To compile this driver as a module, choose M here: the > + module will be called focaltech_fts. > + > config TOUCHSCREEN_FUJITSU > tristate "Fujitsu serial touchscreen" > select SERIO > diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile > index 159cd5136fdb..47d78c9cff21 100644 > --- a/drivers/input/touchscreen/Makefile > +++ b/drivers/input/touchscreen/Makefile > @@ -45,6 +45,7 @@ obj-$(CONFIG_TOUCHSCREEN_ELO) += elo.o > obj-$(CONFIG_TOUCHSCREEN_EGALAX) += egalax_ts.o > obj-$(CONFIG_TOUCHSCREEN_EGALAX_SERIAL) += egalax_ts_serial.o > obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o > +obj-$(CONFIG_TOUCHSCREEN_FOCALTECH_FTS5452) += focaltech_fts5452.o > obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o > obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o > obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o > diff --git a/drivers/input/touchscreen/focaltech_fts5452.c b/drivers/input/touchscreen/focaltech_fts5452.c > new file mode 100644 > index 000000000000..abf8a2f271ca > --- /dev/null > +++ b/drivers/input/touchscreen/focaltech_fts5452.c > @@ -0,0 +1,432 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * FocalTech touchscreen driver. > + * > + * Copyright (c) 2010-2017, FocalTech Systems, Ltd., all rights reserved. > + * Copyright (C) 2018 XiaoMi, Inc. > + * Copyright (c) 2021 Caleb Connolly <caleb@connolly.tech> > + * Copyright (c) 2023 Joel Selvaraj <joelselvaraj.oss@gmail.com> > + */ Nit: inconsistent copyright capitalization. > + > +#include <linux/delay.h> > +#include <linux/i2c.h> > +#include <linux/input.h> > +#include <linux/input/mt.h> > +#include <linux/input/touchscreen.h> > +#include <linux/interrupt.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > +#include <linux/slab.h> > + > +#define FTS_REG_CHIP_ID_H 0xA3 > +#define FTS_REG_CHIP_ID_L 0x9F > + > +#define FTS_MAX_POINTS_SUPPORT 10 > +#define FTS_ONE_TOUCH_LEN 6 > + > +#define FTS_TOUCH_X_H_OFFSET 3 > +#define FTS_TOUCH_X_L_OFFSET 4 > +#define FTS_TOUCH_Y_H_OFFSET 5 > +#define FTS_TOUCH_Y_L_OFFSET 6 > +#define FTS_TOUCH_PRESSURE_OFFSET 7 > +#define FTS_TOUCH_AREA_OFFSET 8 > +#define FTS_TOUCH_TYPE_OFFSET 3 > +#define FTS_TOUCH_ID_OFFSET 5 > + > +#define FTS_TOUCH_DOWN 0 > +#define FTS_TOUCH_UP 1 > +#define FTS_TOUCH_CONTACT 2 > + > +#define FTS_INTERVAL_READ_REG_MS 100 > +#define FTS_TIMEOUT_READ_REG_MS 2000 > + > +#define FTS_DRIVER_NAME "fts-i2c" > + > +static const u16 fts_chip_types[] = { > + 0x5452, > + 0x8719, > +}; > + > +struct fts_ts_data { > + struct i2c_client *client; > + struct input_dev *input_dev; > + struct regmap *regmap; > + int irq; > + struct regulator_bulk_data regulators[2]; > + u8 max_touch_points; > + u8 *point_buf; > + int point_buf_size; > + struct gpio_desc *reset_gpio; > + struct touchscreen_properties prop; > +}; > + > +struct fts_i2c_chip_data { > + int max_touch_points; > +}; There is no reason to wrap a single member in a struct; just define an array and point each driver_data member to the appropriate element. An even better solution, however, would be to merge the device ID into this. Then you would have a single array of structs with very clear association between device ID and number of points. > + > +int fts_check_status(struct fts_ts_data *data) This function can be static. It also seems to be inappropriately named. Here we are checking the device's ID, not its status. > +{ > + int error, i = 0, count = 0; > + unsigned int val, id; > + > + do { > + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_L, &id); > + if (error) > + dev_err(&data->client->dev, "I2C read failed: %d\n", error); If this read fails, there is no point in continuing further in this loop. Most likely the second read would fail as well but if it doesn't, you are computing the id using an uninitialized variable. Can you also explain, and possibly add comments, as to why the device ID must be checked in a retry loop? Is it because the device may be in a deep sleep and must be hit with I2C traffic a couple of times? If so, then you likely want to briefly sleep and then start over (i.e. continue) in the event of an error. > + > + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_H, &val); > + if (error) > + dev_err(&data->client->dev, "I2C read failed: %d\n", error); Same problem here. > + > + id |= val << 8; > + > + for (i = 0; i < ARRAY_SIZE(fts_chip_types); i++) > + if (id == fts_chip_types[i]) > + return 0; This retry loop in general seems a bit non-optimal. If for example the driver is simply communicating with an incompatible device, there is no need to go through all N loops. > + > + count++; > + msleep(FTS_INTERVAL_READ_REG_MS); > + } while ((count * FTS_INTERVAL_READ_REG_MS) < FTS_TIMEOUT_READ_REG_MS); This multiplication seems unnecessarily complicated; can we not simply have FTS_MAX_RETRIES or similar? > + > + return -EIO; > +} > + > +static int fts_report_touch(struct fts_ts_data *data) > +{ > + struct input_dev *input_dev = data->input_dev; > + int base; > + unsigned int x, y, z, maj; > + u8 slot, type; > + int error, i = 0; > + > + u8 *buf = data->point_buf; > + > + memset(buf, 0, data->point_buf_size); > + > + error = regmap_bulk_read(data->regmap, 0, buf, data->point_buf_size); > + if (error) { > + dev_err(&data->client->dev, "I2C read failed: %d\n", error); > + return error; > + } > + > + for (i = 0; i < data->max_touch_points; i++) { > + base = FTS_ONE_TOUCH_LEN * i; > + > + slot = buf[base + FTS_TOUCH_ID_OFFSET] >> 4; > + if (slot >= data->max_touch_points) > + break; > + > + x = ((buf[base + FTS_TOUCH_X_H_OFFSET] & 0x0F) << 8) + > + (buf[base + FTS_TOUCH_X_L_OFFSET] & 0xFF); > + y = ((buf[base + FTS_TOUCH_Y_H_OFFSET] & 0x0F) << 8) + > + (buf[base + FTS_TOUCH_Y_L_OFFSET] & 0xFF); Sorry, I did not quite follow the image that was shared in an earlier thread. It is unclear to me why we cannot represent the interrupt status registers as an array of __be16 values and then do something like the following: x = be16_to_cpu(buf[FTS_TOUCH_X_OFFSET]) & GENMASK(11, 0); I would be surprised if the mask is even necessary; you would need to refer to a datasheet however. Perhaps the vendor would be willing to give one to you if it means they get an upstream driver? > + > + z = buf[base + FTS_TOUCH_PRESSURE_OFFSET]; > + if (z == 0) > + z = 0x3f; > + > + maj = buf[base + FTS_TOUCH_AREA_OFFSET] >> 4; > + if (maj == 0) > + maj = 0x09; I think we need some comments and possibly some #defines to explain what is happening here. > + > + type = buf[base + FTS_TOUCH_TYPE_OFFSET] >> 6; > + > + input_mt_slot(input_dev, slot); > + if (type == FTS_TOUCH_DOWN || type == FTS_TOUCH_CONTACT) { > + input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, true); > + touchscreen_report_pos(data->input_dev, &data->prop, x, y, true); > + input_report_abs(input_dev, ABS_MT_PRESSURE, z); > + input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, maj); > + input_report_key(data->input_dev, BTN_TOUCH, 1); > + } else { > + input_report_key(data->input_dev, BTN_TOUCH, 0); > + input_mt_report_slot_inactive(input_dev); > + } > + } > + input_mt_sync_frame(input_dev); > + input_sync(input_dev); > + > + return 0; > +} > + > +static irqreturn_t fts_ts_interrupt(int irq, void *dev_id) > +{ > + struct fts_ts_data *data = dev_id; > + > + return fts_report_touch(data) ? IRQ_NONE : IRQ_HANDLED; > +} > + > +static void fts_power_off(void *d) > +{ > + struct fts_ts_data *data = d; > + > + regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators); > +} > + > +static int fts_start(struct fts_ts_data *data) > +{ > + int error; > + > + error = regulator_bulk_enable(ARRAY_SIZE(data->regulators), > + data->regulators); > + if (error) { > + dev_err(&data->client->dev, "failed to enable regulators\n"); > + return error; > + } > + > + gpiod_set_value_cansleep(data->reset_gpio, 0); > + msleep(200); Same here with respect to comments; what happens during these first 200 ms after reset is released? Does the interrupt pin toggle several times? 200 ms is also quite a while to wait each time the input handler opens the device; is it really necessary? > + > + enable_irq(data->irq); > + > + return 0; > +} > + > +static int fts_stop(struct fts_ts_data *data) > +{ > + disable_irq(data->irq); > + gpiod_set_value_cansleep(data->reset_gpio, 1); > + fts_power_off(data); > + > + return 0; > +} > + > +static int fts_input_open(struct input_dev *dev) > +{ > + struct fts_ts_data *data = input_get_drvdata(dev); > + int error; > + > + error = fts_start(data); > + if (error) > + return error; > + > + error = fts_check_status(data); > + if (error) { > + dev_err(&data->client->dev, "Failed to start or unsupported chip"); > + return error; > + } It seems unnecessary and wasteful to check the device ID every time the input handler opens the device. We also don't want to go through all the trouble of registering the device, only to find out later it wasn't even the right part. Instead, you should power up the device during probe, validate its ID and then power it back down. > + > + return 0; > +} > + > +static void fts_input_close(struct input_dev *dev) > +{ > + struct fts_ts_data *data = input_get_drvdata(dev); > + > + fts_stop(data); > +} > + > +static int fts_input_init(struct fts_ts_data *data) > +{ > + struct device *dev = &data->client->dev; > + struct input_dev *input_dev; > + int error = 0; No need to initialize this, only for it to get overwritten later. > + > + input_dev = devm_input_allocate_device(dev); > + if (!input_dev) > + return -ENOMEM; > + > + data->input_dev = input_dev; > + > + input_dev->name = FTS_DRIVER_NAME; > + input_dev->id.bustype = BUS_I2C; > + input_dev->dev.parent = dev; > + input_dev->open = fts_input_open; > + input_dev->close = fts_input_close; > + input_set_drvdata(input_dev, data); > + > + input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X); > + input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y); > + input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0); > + input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0); > + > + touchscreen_parse_properties(input_dev, true, &data->prop); > + if (!data->prop.max_x || !data->prop.max_y) { > + dev_err(dev, > + "touchscreen-size-x and/or touchscreen-size-y not set in device properties\n"); "Device properties" is vague; one could interpret it to mean the controller's embedded FW. Just cut the message off at "...not set". > + return -EINVAL; > + } > + > + error = input_mt_init_slots(input_dev, data->max_touch_points, > + INPUT_MT_DIRECT); > + if (error) > + return error; > + > + data->point_buf_size = (data->max_touch_points * FTS_ONE_TOUCH_LEN) + 3; > + data->point_buf = devm_kzalloc(dev, data->point_buf_size, GFP_KERNEL); > + if (!data->point_buf) > + return -ENOMEM; > + > + error = input_register_device(input_dev); > + if (error) { > + dev_err(dev, "Failed to register input device\n"); > + return error; > + } > + > + return 0; > +} > + > +static const struct regmap_config fts_ts_i2c_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > +}; > + > +static int fts_ts_probe(struct i2c_client *client) > +{ > + const struct i2c_device_id *id = i2c_client_get_device_id(client); > + const struct fts_i2c_chip_data *chip_data; > + struct fts_ts_data *data; > + int error = 0; > + > + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { > + dev_err(&client->dev, "I2C not supported"); > + return -ENODEV; > + } > + > + if (!client->irq) { > + dev_err(&client->dev, "No irq specified\n"); > + return -EINVAL; > + } > + > + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + chip_data = device_get_match_data(&client->dev); > + if (!chip_data) > + chip_data = (const struct fts_i2c_chip_data *)id->driver_data; > + if (!chip_data || !chip_data->max_touch_points) { > + dev_err(&client->dev, "invalid or missing chip data\n"); > + return -EINVAL; > + } > + if (chip_data->max_touch_points > FTS_MAX_POINTS_SUPPORT) { > + dev_err(&client->dev, > + "invalid chip data, max_touch_points should be less than or equal to %d\n", > + FTS_MAX_POINTS_SUPPORT); > + return -EINVAL; > + } This check is not necessary; if someone adds an invalid max_touch_points, then the driver was updated incorrectly. There is no need to check it at every runtime. > + data->max_touch_points = chip_data->max_touch_points; > + > + data->client = client; > + i2c_set_clientdata(client, data); > + > + data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH); > + if (IS_ERR(data->reset_gpio)) { > + error = PTR_ERR(data->reset_gpio); > + dev_err(&client->dev, "Failed to request reset gpio, error %d\n", error); > + return error; > + } > + > + data->regmap = devm_regmap_init_i2c(client, &fts_ts_i2c_regmap_config); > + if (IS_ERR(data->regmap)) { > + error = PTR_ERR(data->regmap); > + dev_err(&client->dev, "regmap allocation failed, error %d\n", error); > + return error; > + } > + > + /* > + * AVDD is the analog voltage supply (2.6V to 3.3V) > + * VDDIO is the digital voltage supply (1.8V) > + */ > + data->regulators[0].supply = "avdd"; > + data->regulators[1].supply = "vddio"; > + error = devm_regulator_bulk_get(&client->dev, ARRAY_SIZE(data->regulators), > + data->regulators); > + if (error) { > + dev_err(&client->dev, "Failed to get regulators %d\n", error); > + return error; > + } > + > + error = devm_add_action_or_reset(&client->dev, fts_power_off, data); > + if (error) { > + dev_err(&client->dev, "failed to install power off handler\n"); > + return error; > + } Christophe makes a great point. If this or any other call throughout the rest of probe as you have written it fails, you will try to disable a disabled regulator. The same will happen when the driver is torn down, as the input handler should have already powered down the device by way of the close callback. Did you build this driver as a module and test removal? I suspect you will get a stack trace. I think the call needs to go away altogether. > + > + error = devm_request_threaded_irq(&client->dev, client->irq, NULL, > + fts_ts_interrupt, IRQF_ONESHOT, > + client->name, data); > + if (error) { > + dev_err(&client->dev, "Failed to request IRQ: %d\n", error); > + return error; > + } > + > + error = fts_input_init(data); > + if (error) > + return error; > + > + return 0; This is idiomatic, but I find "return fts_input_init(data);" to be simpler. > +} > + > +static int fts_pm_suspend(struct device *dev) > +{ > + struct fts_ts_data *data = dev_get_drvdata(dev); > + > + mutex_lock(&data->input_dev->mutex); > + > + if (input_device_enabled(data->input_dev)) > + fts_stop(data); > + > + mutex_unlock(&data->input_dev->mutex); > + > + return 0; > +} > + > +static int fts_pm_resume(struct device *dev) > +{ > + struct fts_ts_data *data = dev_get_drvdata(dev); > + int error = 0; Same here, there is no point in initializating this. > + > + mutex_lock(&data->input_dev->mutex); > + > + if (input_device_enabled(data->input_dev)) > + error = fts_start(data); > + > + mutex_unlock(&data->input_dev->mutex); > + > + return error; > +} > + > +static DEFINE_SIMPLE_DEV_PM_OPS(fts_dev_pm_ops, fts_pm_suspend, fts_pm_resume); > + > +static const struct fts_i2c_chip_data fts5452_chip_data = { > + .max_touch_points = 5, > +}; > + > +static const struct fts_i2c_chip_data fts8719_chip_data = { > + .max_touch_points = 10, > +}; > + > +static const struct i2c_device_id fts_i2c_id[] = { > + { .name = "fts5452", .driver_data = (long)&fts5452_chip_data }, > + { .name = "fts8719", .driver_data = (long)&fts8719_chip_data }, > + { /* sentinel */ } > +}; > +MODULE_DEVICE_TABLE(i2c, fts_i2c_id); > + > +static const struct of_device_id fts_of_match[] = { > + { .compatible = "focaltech,fts5452", .data = &fts5452_chip_data }, > + { .compatible = "focaltech,fts8719", .data = &fts8719_chip_data }, > + { /* sentinel */ } > +}; > + > +MODULE_DEVICE_TABLE(of, fts_of_match); > + > +static struct i2c_driver fts_ts_driver = { > + .probe_new = fts_ts_probe, > + .id_table = fts_i2c_id, > + .driver = { > + .name = FTS_DRIVER_NAME, > + .pm = pm_sleep_ptr(&fts_dev_pm_ops), > + .of_match_table = fts_of_match, > + }, > +}; > +module_i2c_driver(fts_ts_driver); > + > +MODULE_AUTHOR("Joel Selvaraj <joelselvaraj.oss@gmail.com>"); > +MODULE_AUTHOR("Caleb Connolly <caleb@connolly.tech>"); > +MODULE_DESCRIPTION("Focaltech Touchscreen Driver"); Nit: mixing 'FocalTech' and 'Focaltech' throughout. > +MODULE_LICENSE("GPL"); > -- > 2.40.0 > Kind regards, Jeff LaBundy
Hi, On 4/24/23 04:39, Jeff LaBundy wrote: > Hi Joel, > > Great work so far! It's coming along nicely. Please find my latest > feedback below. > > On Fri, Apr 14, 2023 at 09:02:19PM -0500, Joel Selvaraj wrote: >> The Focaltech FTS driver supports several variants of focaltech >> touchscreens found in ~2018 era smartphones including variants found on >> the PocoPhone F1 and the SHIFT6mq which are already present in mainline. >> This driver is loosely based on the original driver from Focaltech >> but has been simplified and largely reworked. >> >> Co-developed-by: Caleb Connolly <caleb@connolly.tech> >> Signed-off-by: Caleb Connolly <caleb@connolly.tech> >> Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com> Sorry for jumping into this thread a bit late. I've been reading the archived discussion, but AFAICT the following question is not answered there: Why do a new driver at all ? I have a couple of devices (Nextbook Ares 8, Nextbook Ares 8A) with focaltech FT5416 touchscreens and they both work fine with the existing drivers/input/touchscreen/edt-ft5x06.c driver. Is there any reason we need a whole new driver for the ft5452 instead of using (with maybe some tweaks?) the existing edt-ft5x06 driver ? Note that despite the name the edt-ft5x06 is a generic Focaltect touchscreen driver. Regards, Hans >> --- >> MAINTAINERS | 8 + >> drivers/input/touchscreen/Kconfig | 12 + >> drivers/input/touchscreen/Makefile | 1 + >> drivers/input/touchscreen/focaltech_fts5452.c | 432 ++++++++++++++++++ >> 4 files changed, 453 insertions(+) >> create mode 100644 drivers/input/touchscreen/focaltech_fts5452.c >> >> diff --git a/MAINTAINERS b/MAINTAINERS >> index 7ec4ce64f66d..1a3ea61e1f52 100644 >> --- a/MAINTAINERS >> +++ b/MAINTAINERS >> @@ -8028,6 +8028,14 @@ L: linux-input@vger.kernel.org >> S: Maintained >> F: drivers/input/joystick/fsia6b.c >> >> +FOCALTECH FTS5452 TOUCHSCREEN DRIVER >> +M: Joel Selvaraj <joelselvaraj.oss@gmail.com> >> +M: Caleb Connolly <caleb@connolly.tech> >> +L: linux-input@vger.kernel.org >> +S: Maintained >> +F: Documentation/devicetree/bindings/input/touchscreen/focaltech,fts5452.yaml >> +F: drivers/input/touchscreen/focaltech_fts5452.c >> + >> FOCUSRITE SCARLETT GEN 2/3 MIXER DRIVER >> M: Geoffrey D. Bennett <g@b4.vu> >> L: alsa-devel@alsa-project.org (moderated for non-subscribers) >> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig >> index 1feecd7ed3cb..11af91504969 100644 >> --- a/drivers/input/touchscreen/Kconfig >> +++ b/drivers/input/touchscreen/Kconfig >> @@ -388,6 +388,18 @@ config TOUCHSCREEN_EXC3000 >> To compile this driver as a module, choose M here: the >> module will be called exc3000. >> >> +config TOUCHSCREEN_FOCALTECH_FTS5452 >> + tristate "Focaltech FTS Touchscreen" >> + depends on I2C >> + help >> + Say Y here to enable support for I2C connected Focaltech FTS >> + based touch panels, including the 5452 and 8917 panels. > > This language is a bit misleading, as it seems to suggest three or more > models are supported. It seems the title should simply be "FocalTech > FTS5452 touchscreen controller" with the description as "...FocalTech > FTS5452 and compatible touchscreen controllers." > > As more are found to be compatible (e.g. FTS8917), the compatible strings > can simply be appended. > >> + >> + If unsure, say N. >> + >> + To compile this driver as a module, choose M here: the >> + module will be called focaltech_fts. >> + >> config TOUCHSCREEN_FUJITSU >> tristate "Fujitsu serial touchscreen" >> select SERIO >> diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile >> index 159cd5136fdb..47d78c9cff21 100644 >> --- a/drivers/input/touchscreen/Makefile >> +++ b/drivers/input/touchscreen/Makefile >> @@ -45,6 +45,7 @@ obj-$(CONFIG_TOUCHSCREEN_ELO) += elo.o >> obj-$(CONFIG_TOUCHSCREEN_EGALAX) += egalax_ts.o >> obj-$(CONFIG_TOUCHSCREEN_EGALAX_SERIAL) += egalax_ts_serial.o >> obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o >> +obj-$(CONFIG_TOUCHSCREEN_FOCALTECH_FTS5452) += focaltech_fts5452.o >> obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o >> obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o >> obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o >> diff --git a/drivers/input/touchscreen/focaltech_fts5452.c b/drivers/input/touchscreen/focaltech_fts5452.c >> new file mode 100644 >> index 000000000000..abf8a2f271ca >> --- /dev/null >> +++ b/drivers/input/touchscreen/focaltech_fts5452.c >> @@ -0,0 +1,432 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * FocalTech touchscreen driver. >> + * >> + * Copyright (c) 2010-2017, FocalTech Systems, Ltd., all rights reserved. >> + * Copyright (C) 2018 XiaoMi, Inc. >> + * Copyright (c) 2021 Caleb Connolly <caleb@connolly.tech> >> + * Copyright (c) 2023 Joel Selvaraj <joelselvaraj.oss@gmail.com> >> + */ > > Nit: inconsistent copyright capitalization. > >> + >> +#include <linux/delay.h> >> +#include <linux/i2c.h> >> +#include <linux/input.h> >> +#include <linux/input/mt.h> >> +#include <linux/input/touchscreen.h> >> +#include <linux/interrupt.h> >> +#include <linux/kernel.h> >> +#include <linux/module.h> >> +#include <linux/mutex.h> >> +#include <linux/regmap.h> >> +#include <linux/regulator/consumer.h> >> +#include <linux/slab.h> >> + >> +#define FTS_REG_CHIP_ID_H 0xA3 >> +#define FTS_REG_CHIP_ID_L 0x9F >> + >> +#define FTS_MAX_POINTS_SUPPORT 10 >> +#define FTS_ONE_TOUCH_LEN 6 >> + >> +#define FTS_TOUCH_X_H_OFFSET 3 >> +#define FTS_TOUCH_X_L_OFFSET 4 >> +#define FTS_TOUCH_Y_H_OFFSET 5 >> +#define FTS_TOUCH_Y_L_OFFSET 6 >> +#define FTS_TOUCH_PRESSURE_OFFSET 7 >> +#define FTS_TOUCH_AREA_OFFSET 8 >> +#define FTS_TOUCH_TYPE_OFFSET 3 >> +#define FTS_TOUCH_ID_OFFSET 5 >> + >> +#define FTS_TOUCH_DOWN 0 >> +#define FTS_TOUCH_UP 1 >> +#define FTS_TOUCH_CONTACT 2 >> + >> +#define FTS_INTERVAL_READ_REG_MS 100 >> +#define FTS_TIMEOUT_READ_REG_MS 2000 >> + >> +#define FTS_DRIVER_NAME "fts-i2c" >> + >> +static const u16 fts_chip_types[] = { >> + 0x5452, >> + 0x8719, >> +}; >> + >> +struct fts_ts_data { >> + struct i2c_client *client; >> + struct input_dev *input_dev; >> + struct regmap *regmap; >> + int irq; >> + struct regulator_bulk_data regulators[2]; >> + u8 max_touch_points; >> + u8 *point_buf; >> + int point_buf_size; >> + struct gpio_desc *reset_gpio; >> + struct touchscreen_properties prop; >> +}; >> + >> +struct fts_i2c_chip_data { >> + int max_touch_points; >> +}; > > There is no reason to wrap a single member in a struct; just define an array > and point each driver_data member to the appropriate element. > > An even better solution, however, would be to merge the device ID into this. > Then you would have a single array of structs with very clear association > between device ID and number of points. > >> + >> +int fts_check_status(struct fts_ts_data *data) > > This function can be static. It also seems to be inappropriately named. Here > we are checking the device's ID, not its status. > >> +{ >> + int error, i = 0, count = 0; >> + unsigned int val, id; >> + >> + do { >> + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_L, &id); >> + if (error) >> + dev_err(&data->client->dev, "I2C read failed: %d\n", error); > > If this read fails, there is no point in continuing further in this loop. Most > likely the second read would fail as well but if it doesn't, you are computing > the id using an uninitialized variable. > > Can you also explain, and possibly add comments, as to why the device ID must > be checked in a retry loop? Is it because the device may be in a deep sleep and > must be hit with I2C traffic a couple of times? > > If so, then you likely want to briefly sleep and then start over (i.e. continue) > in the event of an error. > >> + >> + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_H, &val); >> + if (error) >> + dev_err(&data->client->dev, "I2C read failed: %d\n", error); > > Same problem here. > >> + >> + id |= val << 8; >> + >> + for (i = 0; i < ARRAY_SIZE(fts_chip_types); i++) >> + if (id == fts_chip_types[i]) >> + return 0; > > This retry loop in general seems a bit non-optimal. If for example the driver > is simply communicating with an incompatible device, there is no need to go > through all N loops. > >> + >> + count++; >> + msleep(FTS_INTERVAL_READ_REG_MS); >> + } while ((count * FTS_INTERVAL_READ_REG_MS) < FTS_TIMEOUT_READ_REG_MS); > > This multiplication seems unnecessarily complicated; can we not simply have > FTS_MAX_RETRIES or similar? > >> + >> + return -EIO; >> +} >> + >> +static int fts_report_touch(struct fts_ts_data *data) >> +{ >> + struct input_dev *input_dev = data->input_dev; >> + int base; >> + unsigned int x, y, z, maj; >> + u8 slot, type; >> + int error, i = 0; >> + >> + u8 *buf = data->point_buf; >> + >> + memset(buf, 0, data->point_buf_size); >> + >> + error = regmap_bulk_read(data->regmap, 0, buf, data->point_buf_size); >> + if (error) { >> + dev_err(&data->client->dev, "I2C read failed: %d\n", error); >> + return error; >> + } >> + >> + for (i = 0; i < data->max_touch_points; i++) { >> + base = FTS_ONE_TOUCH_LEN * i; >> + >> + slot = buf[base + FTS_TOUCH_ID_OFFSET] >> 4; >> + if (slot >= data->max_touch_points) >> + break; >> + >> + x = ((buf[base + FTS_TOUCH_X_H_OFFSET] & 0x0F) << 8) + >> + (buf[base + FTS_TOUCH_X_L_OFFSET] & 0xFF); >> + y = ((buf[base + FTS_TOUCH_Y_H_OFFSET] & 0x0F) << 8) + >> + (buf[base + FTS_TOUCH_Y_L_OFFSET] & 0xFF); > > Sorry, I did not quite follow the image that was shared in an earlier thread. > It is unclear to me why we cannot represent the interrupt status registers > as an array of __be16 values and then do something like the following: > > x = be16_to_cpu(buf[FTS_TOUCH_X_OFFSET]) & GENMASK(11, 0); > > I would be surprised if the mask is even necessary; you would need to refer > to a datasheet however. Perhaps the vendor would be willing to give one to > you if it means they get an upstream driver? > >> + >> + z = buf[base + FTS_TOUCH_PRESSURE_OFFSET]; >> + if (z == 0) >> + z = 0x3f; >> + >> + maj = buf[base + FTS_TOUCH_AREA_OFFSET] >> 4; >> + if (maj == 0) >> + maj = 0x09; > > I think we need some comments and possibly some #defines to explain what is > happening here. > >> + >> + type = buf[base + FTS_TOUCH_TYPE_OFFSET] >> 6; >> + >> + input_mt_slot(input_dev, slot); >> + if (type == FTS_TOUCH_DOWN || type == FTS_TOUCH_CONTACT) { >> + input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, true); >> + touchscreen_report_pos(data->input_dev, &data->prop, x, y, true); >> + input_report_abs(input_dev, ABS_MT_PRESSURE, z); >> + input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, maj); >> + input_report_key(data->input_dev, BTN_TOUCH, 1); >> + } else { >> + input_report_key(data->input_dev, BTN_TOUCH, 0); >> + input_mt_report_slot_inactive(input_dev); >> + } >> + } >> + input_mt_sync_frame(input_dev); >> + input_sync(input_dev); >> + >> + return 0; >> +} >> + >> +static irqreturn_t fts_ts_interrupt(int irq, void *dev_id) >> +{ >> + struct fts_ts_data *data = dev_id; >> + >> + return fts_report_touch(data) ? IRQ_NONE : IRQ_HANDLED; >> +} >> + >> +static void fts_power_off(void *d) >> +{ >> + struct fts_ts_data *data = d; >> + >> + regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators); >> +} >> + >> +static int fts_start(struct fts_ts_data *data) >> +{ >> + int error; >> + >> + error = regulator_bulk_enable(ARRAY_SIZE(data->regulators), >> + data->regulators); >> + if (error) { >> + dev_err(&data->client->dev, "failed to enable regulators\n"); >> + return error; >> + } >> + >> + gpiod_set_value_cansleep(data->reset_gpio, 0); >> + msleep(200); > > Same here with respect to comments; what happens during these first 200 ms after > reset is released? Does the interrupt pin toggle several times? 200 ms is also > quite a while to wait each time the input handler opens the device; is it really > necessary? > >> + >> + enable_irq(data->irq); >> + >> + return 0; >> +} >> + >> +static int fts_stop(struct fts_ts_data *data) >> +{ >> + disable_irq(data->irq); >> + gpiod_set_value_cansleep(data->reset_gpio, 1); >> + fts_power_off(data); >> + >> + return 0; >> +} >> + >> +static int fts_input_open(struct input_dev *dev) >> +{ >> + struct fts_ts_data *data = input_get_drvdata(dev); >> + int error; >> + >> + error = fts_start(data); >> + if (error) >> + return error; >> + >> + error = fts_check_status(data); >> + if (error) { >> + dev_err(&data->client->dev, "Failed to start or unsupported chip"); >> + return error; >> + } > > It seems unnecessary and wasteful to check the device ID every time the input > handler opens the device. We also don't want to go through all the trouble of > registering the device, only to find out later it wasn't even the right part. > > Instead, you should power up the device during probe, validate its ID and then > power it back down. > >> + >> + return 0; >> +} >> + >> +static void fts_input_close(struct input_dev *dev) >> +{ >> + struct fts_ts_data *data = input_get_drvdata(dev); >> + >> + fts_stop(data); >> +} >> + >> +static int fts_input_init(struct fts_ts_data *data) >> +{ >> + struct device *dev = &data->client->dev; >> + struct input_dev *input_dev; >> + int error = 0; > > No need to initialize this, only for it to get overwritten later. > >> + >> + input_dev = devm_input_allocate_device(dev); >> + if (!input_dev) >> + return -ENOMEM; >> + >> + data->input_dev = input_dev; >> + >> + input_dev->name = FTS_DRIVER_NAME; >> + input_dev->id.bustype = BUS_I2C; >> + input_dev->dev.parent = dev; >> + input_dev->open = fts_input_open; >> + input_dev->close = fts_input_close; >> + input_set_drvdata(input_dev, data); >> + >> + input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X); >> + input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y); >> + input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0); >> + input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0); >> + >> + touchscreen_parse_properties(input_dev, true, &data->prop); >> + if (!data->prop.max_x || !data->prop.max_y) { >> + dev_err(dev, >> + "touchscreen-size-x and/or touchscreen-size-y not set in device properties\n"); > > "Device properties" is vague; one could interpret it to mean the controller's > embedded FW. Just cut the message off at "...not set". > >> + return -EINVAL; >> + } >> + >> + error = input_mt_init_slots(input_dev, data->max_touch_points, >> + INPUT_MT_DIRECT); >> + if (error) >> + return error; >> + >> + data->point_buf_size = (data->max_touch_points * FTS_ONE_TOUCH_LEN) + 3; >> + data->point_buf = devm_kzalloc(dev, data->point_buf_size, GFP_KERNEL); >> + if (!data->point_buf) >> + return -ENOMEM; >> + >> + error = input_register_device(input_dev); >> + if (error) { >> + dev_err(dev, "Failed to register input device\n"); >> + return error; >> + } >> + >> + return 0; >> +} >> + >> +static const struct regmap_config fts_ts_i2c_regmap_config = { >> + .reg_bits = 8, >> + .val_bits = 8, >> +}; >> + >> +static int fts_ts_probe(struct i2c_client *client) >> +{ >> + const struct i2c_device_id *id = i2c_client_get_device_id(client); >> + const struct fts_i2c_chip_data *chip_data; >> + struct fts_ts_data *data; >> + int error = 0; >> + >> + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { >> + dev_err(&client->dev, "I2C not supported"); >> + return -ENODEV; >> + } >> + >> + if (!client->irq) { >> + dev_err(&client->dev, "No irq specified\n"); >> + return -EINVAL; >> + } >> + >> + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); >> + if (!data) >> + return -ENOMEM; >> + >> + chip_data = device_get_match_data(&client->dev); >> + if (!chip_data) >> + chip_data = (const struct fts_i2c_chip_data *)id->driver_data; >> + if (!chip_data || !chip_data->max_touch_points) { >> + dev_err(&client->dev, "invalid or missing chip data\n"); >> + return -EINVAL; >> + } >> + if (chip_data->max_touch_points > FTS_MAX_POINTS_SUPPORT) { >> + dev_err(&client->dev, >> + "invalid chip data, max_touch_points should be less than or equal to %d\n", >> + FTS_MAX_POINTS_SUPPORT); >> + return -EINVAL; >> + } > > This check is not necessary; if someone adds an invalid max_touch_points, then the > driver was updated incorrectly. There is no need to check it at every runtime. > >> + data->max_touch_points = chip_data->max_touch_points; >> + >> + data->client = client; >> + i2c_set_clientdata(client, data); >> + >> + data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH); >> + if (IS_ERR(data->reset_gpio)) { >> + error = PTR_ERR(data->reset_gpio); >> + dev_err(&client->dev, "Failed to request reset gpio, error %d\n", error); >> + return error; >> + } >> + >> + data->regmap = devm_regmap_init_i2c(client, &fts_ts_i2c_regmap_config); >> + if (IS_ERR(data->regmap)) { >> + error = PTR_ERR(data->regmap); >> + dev_err(&client->dev, "regmap allocation failed, error %d\n", error); >> + return error; >> + } >> + >> + /* >> + * AVDD is the analog voltage supply (2.6V to 3.3V) >> + * VDDIO is the digital voltage supply (1.8V) >> + */ >> + data->regulators[0].supply = "avdd"; >> + data->regulators[1].supply = "vddio"; >> + error = devm_regulator_bulk_get(&client->dev, ARRAY_SIZE(data->regulators), >> + data->regulators); >> + if (error) { >> + dev_err(&client->dev, "Failed to get regulators %d\n", error); >> + return error; >> + } >> + >> + error = devm_add_action_or_reset(&client->dev, fts_power_off, data); >> + if (error) { >> + dev_err(&client->dev, "failed to install power off handler\n"); >> + return error; >> + } > > Christophe makes a great point. If this or any other call throughout the rest of > probe as you have written it fails, you will try to disable a disabled regulator. > > The same will happen when the driver is torn down, as the input handler should > have already powered down the device by way of the close callback. Did you build > this driver as a module and test removal? I suspect you will get a stack trace. > > I think the call needs to go away altogether. > >> + >> + error = devm_request_threaded_irq(&client->dev, client->irq, NULL, >> + fts_ts_interrupt, IRQF_ONESHOT, >> + client->name, data); >> + if (error) { >> + dev_err(&client->dev, "Failed to request IRQ: %d\n", error); >> + return error; >> + } >> + >> + error = fts_input_init(data); >> + if (error) >> + return error; >> + >> + return 0; > > This is idiomatic, but I find "return fts_input_init(data);" to be simpler. > >> +} >> + >> +static int fts_pm_suspend(struct device *dev) >> +{ >> + struct fts_ts_data *data = dev_get_drvdata(dev); >> + >> + mutex_lock(&data->input_dev->mutex); >> + >> + if (input_device_enabled(data->input_dev)) >> + fts_stop(data); >> + >> + mutex_unlock(&data->input_dev->mutex); >> + >> + return 0; >> +} >> + >> +static int fts_pm_resume(struct device *dev) >> +{ >> + struct fts_ts_data *data = dev_get_drvdata(dev); >> + int error = 0; > > Same here, there is no point in initializating this. > >> + >> + mutex_lock(&data->input_dev->mutex); >> + >> + if (input_device_enabled(data->input_dev)) >> + error = fts_start(data); >> + >> + mutex_unlock(&data->input_dev->mutex); >> + >> + return error; >> +} >> + >> +static DEFINE_SIMPLE_DEV_PM_OPS(fts_dev_pm_ops, fts_pm_suspend, fts_pm_resume); >> + >> +static const struct fts_i2c_chip_data fts5452_chip_data = { >> + .max_touch_points = 5, >> +}; >> + >> +static const struct fts_i2c_chip_data fts8719_chip_data = { >> + .max_touch_points = 10, >> +}; >> + >> +static const struct i2c_device_id fts_i2c_id[] = { >> + { .name = "fts5452", .driver_data = (long)&fts5452_chip_data }, >> + { .name = "fts8719", .driver_data = (long)&fts8719_chip_data }, >> + { /* sentinel */ } >> +}; >> +MODULE_DEVICE_TABLE(i2c, fts_i2c_id); >> + >> +static const struct of_device_id fts_of_match[] = { >> + { .compatible = "focaltech,fts5452", .data = &fts5452_chip_data }, >> + { .compatible = "focaltech,fts8719", .data = &fts8719_chip_data }, >> + { /* sentinel */ } >> +}; >> + >> +MODULE_DEVICE_TABLE(of, fts_of_match); >> + >> +static struct i2c_driver fts_ts_driver = { >> + .probe_new = fts_ts_probe, >> + .id_table = fts_i2c_id, >> + .driver = { >> + .name = FTS_DRIVER_NAME, >> + .pm = pm_sleep_ptr(&fts_dev_pm_ops), >> + .of_match_table = fts_of_match, >> + }, >> +}; >> +module_i2c_driver(fts_ts_driver); >> + >> +MODULE_AUTHOR("Joel Selvaraj <joelselvaraj.oss@gmail.com>"); >> +MODULE_AUTHOR("Caleb Connolly <caleb@connolly.tech>"); >> +MODULE_DESCRIPTION("Focaltech Touchscreen Driver"); > > Nit: mixing 'FocalTech' and 'Focaltech' throughout. > >> +MODULE_LICENSE("GPL"); >> -- >> 2.40.0 >> > > Kind regards, > Jeff LaBundy >
Hi Jeff LaBundy, On 4/23/23 21:39, Jeff LaBundy wrote: > Hi Joel, > > Great work so far! It's coming along nicely. Please find my latest > feedback below. Sorry for the late reply, university semester end got me hooked up. I have a sad kind of good news... As pointed out by Hans de Goede, the edt-ft5x06 driver works out of the box for the fts8719 touchscreen in my device. So I think this patch series is no longer needed. I did have a look at the driver once when working on this patch series, but it looked different/not compatible at that time. After mentioned by Hans de Goede, I had a more closer look and the main touch buffer handling seems to be the same. I am sorry as we put some considerable time in this patch series. I should have noted more carefully. Thank you though as I learnt things working on this patch series. I guess I will send a different patch to add the compatible data to the existing edt-ft5x06 driver and dts changes to include that driver to my device. > On Fri, Apr 14, 2023 at 09:02:19PM -0500, Joel Selvaraj wrote: >> The Focaltech FTS driver supports several variants of focaltech >> touchscreens found in ~2018 era smartphones including variants found on >> the PocoPhone F1 and the SHIFT6mq which are already present in mainline. >> This driver is loosely based on the original driver from Focaltech >> but has been simplified and largely reworked. >> >> Co-developed-by: Caleb Connolly <caleb@connolly.tech> >> Signed-off-by: Caleb Connolly <caleb@connolly.tech> >> Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com> >> --- >> MAINTAINERS | 8 + >> drivers/input/touchscreen/Kconfig | 12 + >> drivers/input/touchscreen/Makefile | 1 + >> drivers/input/touchscreen/focaltech_fts5452.c | 432 ++++++++++++++++++ >> 4 files changed, 453 insertions(+) >> create mode 100644 drivers/input/touchscreen/focaltech_fts5452.c >> >> diff --git a/MAINTAINERS b/MAINTAINERS >> index 7ec4ce64f66d..1a3ea61e1f52 100644 >> --- a/MAINTAINERS >> +++ b/MAINTAINERS >> @@ -8028,6 +8028,14 @@ L: linux-input@vger.kernel.org >> S: Maintained >> F: drivers/input/joystick/fsia6b.c >> >> +FOCALTECH FTS5452 TOUCHSCREEN DRIVER >> +M: Joel Selvaraj <joelselvaraj.oss@gmail.com> >> +M: Caleb Connolly <caleb@connolly.tech> >> +L: linux-input@vger.kernel.org >> +S: Maintained >> +F: Documentation/devicetree/bindings/input/touchscreen/focaltech,fts5452.yaml >> +F: drivers/input/touchscreen/focaltech_fts5452.c >> + >> FOCUSRITE SCARLETT GEN 2/3 MIXER DRIVER >> M: Geoffrey D. Bennett <g@b4.vu> >> L: alsa-devel@alsa-project.org (moderated for non-subscribers) >> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig >> index 1feecd7ed3cb..11af91504969 100644 >> --- a/drivers/input/touchscreen/Kconfig >> +++ b/drivers/input/touchscreen/Kconfig >> @@ -388,6 +388,18 @@ config TOUCHSCREEN_EXC3000 >> To compile this driver as a module, choose M here: the >> module will be called exc3000. >> >> +config TOUCHSCREEN_FOCALTECH_FTS5452 >> + tristate "Focaltech FTS Touchscreen" >> + depends on I2C >> + help >> + Say Y here to enable support for I2C connected Focaltech FTS >> + based touch panels, including the 5452 and 8917 panels. > > This language is a bit misleading, as it seems to suggest three or more > models are supported. It seems the title should simply be "FocalTech > FTS5452 touchscreen controller" with the description as "...FocalTech > FTS5452 and compatible touchscreen controllers." > > As more are found to be compatible (e.g. FTS8917), the compatible strings > can simply be appended. > >> + >> + If unsure, say N. >> + >> + To compile this driver as a module, choose M here: the >> + module will be called focaltech_fts. >> + >> config TOUCHSCREEN_FUJITSU >> tristate "Fujitsu serial touchscreen" >> select SERIO >> diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile >> index 159cd5136fdb..47d78c9cff21 100644 >> --- a/drivers/input/touchscreen/Makefile >> +++ b/drivers/input/touchscreen/Makefile >> @@ -45,6 +45,7 @@ obj-$(CONFIG_TOUCHSCREEN_ELO) += elo.o >> obj-$(CONFIG_TOUCHSCREEN_EGALAX) += egalax_ts.o >> obj-$(CONFIG_TOUCHSCREEN_EGALAX_SERIAL) += egalax_ts_serial.o >> obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o >> +obj-$(CONFIG_TOUCHSCREEN_FOCALTECH_FTS5452) += focaltech_fts5452.o >> obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o >> obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o >> obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o >> diff --git a/drivers/input/touchscreen/focaltech_fts5452.c b/drivers/input/touchscreen/focaltech_fts5452.c >> new file mode 100644 >> index 000000000000..abf8a2f271ca >> --- /dev/null >> +++ b/drivers/input/touchscreen/focaltech_fts5452.c >> @@ -0,0 +1,432 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * FocalTech touchscreen driver. >> + * >> + * Copyright (c) 2010-2017, FocalTech Systems, Ltd., all rights reserved. >> + * Copyright (C) 2018 XiaoMi, Inc. >> + * Copyright (c) 2021 Caleb Connolly <caleb@connolly.tech> >> + * Copyright (c) 2023 Joel Selvaraj <joelselvaraj.oss@gmail.com> >> + */ [skip] >> +static const struct of_device_id fts_of_match[] = { >> + { .compatible = "focaltech,fts5452", .data = &fts5452_chip_data }, >> + { .compatible = "focaltech,fts8719", .data = &fts8719_chip_data }, >> + { /* sentinel */ } >> +}; >> + >> +MODULE_DEVICE_TABLE(of, fts_of_match); >> + >> +static struct i2c_driver fts_ts_driver = { >> + .probe_new = fts_ts_probe, >> + .id_table = fts_i2c_id, >> + .driver = { >> + .name = FTS_DRIVER_NAME, >> + .pm = pm_sleep_ptr(&fts_dev_pm_ops), >> + .of_match_table = fts_of_match, >> + }, >> +}; >> +module_i2c_driver(fts_ts_driver); >> + >> +MODULE_AUTHOR("Joel Selvaraj <joelselvaraj.oss@gmail.com>"); >> +MODULE_AUTHOR("Caleb Connolly <caleb@connolly.tech>"); >> +MODULE_DESCRIPTION("Focaltech Touchscreen Driver"); > > Nit: mixing 'FocalTech' and 'Focaltech' throughout. > >> +MODULE_LICENSE("GPL"); >> -- >> 2.40.0 >> > > Kind regards, > Jeff LaBundy Thank you, Joel Selvaraj
Hi Joel, On Thu, May 11, 2023 at 07:43:28PM -0500, Joel Selvaraj wrote: > Hi Jeff LaBundy, > > On 4/23/23 21:39, Jeff LaBundy wrote: > > Hi Joel, > > > > Great work so far! It's coming along nicely. Please find my latest > > feedback below. > > Sorry for the late reply, university semester end got me hooked up. > I have a sad kind of good news... As pointed out by Hans de Goede, the > edt-ft5x06 driver works out of the box for the fts8719 touchscreen in my > device. So I think this patch series is no longer needed. I did have a look > at the driver once when working on this patch series, but it looked > different/not compatible at that time. After mentioned by Hans de Goede, I > had a more closer look and the main touch buffer handling seems to be the > same. > > I am sorry as we put some considerable time in this patch series. I should > have noted more carefully. Thank you though as I learnt things working on > this patch series. There is absolutely no need to apologize; the review process is just as informative for the reviewer as it is the reviewee. The important thing is that the most optimal solution lands. "Less code is the best code" :) > > I guess I will send a different patch to add the compatible data to the > existing edt-ft5x06 driver and dts changes to include that driver to my > device. Sounds great. > > > On Fri, Apr 14, 2023 at 09:02:19PM -0500, Joel Selvaraj wrote: > > > The Focaltech FTS driver supports several variants of focaltech > > > touchscreens found in ~2018 era smartphones including variants found on > > > the PocoPhone F1 and the SHIFT6mq which are already present in mainline. > > > This driver is loosely based on the original driver from Focaltech > > > but has been simplified and largely reworked. > > > > > > Co-developed-by: Caleb Connolly <caleb@connolly.tech> > > > Signed-off-by: Caleb Connolly <caleb@connolly.tech> > > > Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com> > > > --- > > > MAINTAINERS | 8 + > > > drivers/input/touchscreen/Kconfig | 12 + > > > drivers/input/touchscreen/Makefile | 1 + > > > drivers/input/touchscreen/focaltech_fts5452.c | 432 ++++++++++++++++++ > > > 4 files changed, 453 insertions(+) > > > create mode 100644 drivers/input/touchscreen/focaltech_fts5452.c > > > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > > index 7ec4ce64f66d..1a3ea61e1f52 100644 > > > --- a/MAINTAINERS > > > +++ b/MAINTAINERS > > > @@ -8028,6 +8028,14 @@ L: linux-input@vger.kernel.org > > > S: Maintained > > > F: drivers/input/joystick/fsia6b.c > > > +FOCALTECH FTS5452 TOUCHSCREEN DRIVER > > > +M: Joel Selvaraj <joelselvaraj.oss@gmail.com> > > > +M: Caleb Connolly <caleb@connolly.tech> > > > +L: linux-input@vger.kernel.org > > > +S: Maintained > > > +F: Documentation/devicetree/bindings/input/touchscreen/focaltech,fts5452.yaml > > > +F: drivers/input/touchscreen/focaltech_fts5452.c > > > + > > > FOCUSRITE SCARLETT GEN 2/3 MIXER DRIVER > > > M: Geoffrey D. Bennett <g@b4.vu> > > > L: alsa-devel@alsa-project.org (moderated for non-subscribers) > > > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig > > > index 1feecd7ed3cb..11af91504969 100644 > > > --- a/drivers/input/touchscreen/Kconfig > > > +++ b/drivers/input/touchscreen/Kconfig > > > @@ -388,6 +388,18 @@ config TOUCHSCREEN_EXC3000 > > > To compile this driver as a module, choose M here: the > > > module will be called exc3000. > > > +config TOUCHSCREEN_FOCALTECH_FTS5452 > > > + tristate "Focaltech FTS Touchscreen" > > > + depends on I2C > > > + help > > > + Say Y here to enable support for I2C connected Focaltech FTS > > > + based touch panels, including the 5452 and 8917 panels. > > > > This language is a bit misleading, as it seems to suggest three or more > > models are supported. It seems the title should simply be "FocalTech > > FTS5452 touchscreen controller" with the description as "...FocalTech > > FTS5452 and compatible touchscreen controllers." > > > > As more are found to be compatible (e.g. FTS8917), the compatible strings > > can simply be appended. > > > > > + > > > + If unsure, say N. > > > + > > > + To compile this driver as a module, choose M here: the > > > + module will be called focaltech_fts. > > > + > > > config TOUCHSCREEN_FUJITSU > > > tristate "Fujitsu serial touchscreen" > > > select SERIO > > > diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile > > > index 159cd5136fdb..47d78c9cff21 100644 > > > --- a/drivers/input/touchscreen/Makefile > > > +++ b/drivers/input/touchscreen/Makefile > > > @@ -45,6 +45,7 @@ obj-$(CONFIG_TOUCHSCREEN_ELO) += elo.o > > > obj-$(CONFIG_TOUCHSCREEN_EGALAX) += egalax_ts.o > > > obj-$(CONFIG_TOUCHSCREEN_EGALAX_SERIAL) += egalax_ts_serial.o > > > obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o > > > +obj-$(CONFIG_TOUCHSCREEN_FOCALTECH_FTS5452) += focaltech_fts5452.o > > > obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o > > > obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o > > > obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o > > > diff --git a/drivers/input/touchscreen/focaltech_fts5452.c b/drivers/input/touchscreen/focaltech_fts5452.c > > > new file mode 100644 > > > index 000000000000..abf8a2f271ca > > > --- /dev/null > > > +++ b/drivers/input/touchscreen/focaltech_fts5452.c > > > @@ -0,0 +1,432 @@ > > > +// SPDX-License-Identifier: GPL-2.0-only > > > +/* > > > + * FocalTech touchscreen driver. > > > + * > > > + * Copyright (c) 2010-2017, FocalTech Systems, Ltd., all rights reserved. > > > + * Copyright (C) 2018 XiaoMi, Inc. > > > + * Copyright (c) 2021 Caleb Connolly <caleb@connolly.tech> > > > + * Copyright (c) 2023 Joel Selvaraj <joelselvaraj.oss@gmail.com> > > > + */ > > [skip] > > > > +static const struct of_device_id fts_of_match[] = { > > > + { .compatible = "focaltech,fts5452", .data = &fts5452_chip_data }, > > > + { .compatible = "focaltech,fts8719", .data = &fts8719_chip_data }, > > > + { /* sentinel */ } > > > +}; > > > + > > > +MODULE_DEVICE_TABLE(of, fts_of_match); > > > + > > > +static struct i2c_driver fts_ts_driver = { > > > + .probe_new = fts_ts_probe, > > > + .id_table = fts_i2c_id, > > > + .driver = { > > > + .name = FTS_DRIVER_NAME, > > > + .pm = pm_sleep_ptr(&fts_dev_pm_ops), > > > + .of_match_table = fts_of_match, > > > + }, > > > +}; > > > +module_i2c_driver(fts_ts_driver); > > > + > > > +MODULE_AUTHOR("Joel Selvaraj <joelselvaraj.oss@gmail.com>"); > > > +MODULE_AUTHOR("Caleb Connolly <caleb@connolly.tech>"); > > > +MODULE_DESCRIPTION("Focaltech Touchscreen Driver"); > > > > Nit: mixing 'FocalTech' and 'Focaltech' throughout. > > > > > +MODULE_LICENSE("GPL"); > > > -- > > > 2.40.0 > > > > > > > Kind regards, > > Jeff LaBundy > > Thank you, > Joel Selvaraj Kind regards, Jeff LaBundy
diff --git a/MAINTAINERS b/MAINTAINERS index 7ec4ce64f66d..1a3ea61e1f52 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8028,6 +8028,14 @@ L: linux-input@vger.kernel.org S: Maintained F: drivers/input/joystick/fsia6b.c +FOCALTECH FTS5452 TOUCHSCREEN DRIVER +M: Joel Selvaraj <joelselvaraj.oss@gmail.com> +M: Caleb Connolly <caleb@connolly.tech> +L: linux-input@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/input/touchscreen/focaltech,fts5452.yaml +F: drivers/input/touchscreen/focaltech_fts5452.c + FOCUSRITE SCARLETT GEN 2/3 MIXER DRIVER M: Geoffrey D. Bennett <g@b4.vu> L: alsa-devel@alsa-project.org (moderated for non-subscribers) diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index 1feecd7ed3cb..11af91504969 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -388,6 +388,18 @@ config TOUCHSCREEN_EXC3000 To compile this driver as a module, choose M here: the module will be called exc3000. +config TOUCHSCREEN_FOCALTECH_FTS5452 + tristate "Focaltech FTS Touchscreen" + depends on I2C + help + Say Y here to enable support for I2C connected Focaltech FTS + based touch panels, including the 5452 and 8917 panels. + + If unsure, say N. + + To compile this driver as a module, choose M here: the + module will be called focaltech_fts. + config TOUCHSCREEN_FUJITSU tristate "Fujitsu serial touchscreen" select SERIO diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index 159cd5136fdb..47d78c9cff21 100644 --- a/drivers/input/touchscreen/Makefile +++ b/drivers/input/touchscreen/Makefile @@ -45,6 +45,7 @@ obj-$(CONFIG_TOUCHSCREEN_ELO) += elo.o obj-$(CONFIG_TOUCHSCREEN_EGALAX) += egalax_ts.o obj-$(CONFIG_TOUCHSCREEN_EGALAX_SERIAL) += egalax_ts_serial.o obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o +obj-$(CONFIG_TOUCHSCREEN_FOCALTECH_FTS5452) += focaltech_fts5452.o obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o diff --git a/drivers/input/touchscreen/focaltech_fts5452.c b/drivers/input/touchscreen/focaltech_fts5452.c new file mode 100644 index 000000000000..abf8a2f271ca --- /dev/null +++ b/drivers/input/touchscreen/focaltech_fts5452.c @@ -0,0 +1,432 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * FocalTech touchscreen driver. + * + * Copyright (c) 2010-2017, FocalTech Systems, Ltd., all rights reserved. + * Copyright (C) 2018 XiaoMi, Inc. + * Copyright (c) 2021 Caleb Connolly <caleb@connolly.tech> + * Copyright (c) 2023 Joel Selvaraj <joelselvaraj.oss@gmail.com> + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/input/mt.h> +#include <linux/input/touchscreen.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> + +#define FTS_REG_CHIP_ID_H 0xA3 +#define FTS_REG_CHIP_ID_L 0x9F + +#define FTS_MAX_POINTS_SUPPORT 10 +#define FTS_ONE_TOUCH_LEN 6 + +#define FTS_TOUCH_X_H_OFFSET 3 +#define FTS_TOUCH_X_L_OFFSET 4 +#define FTS_TOUCH_Y_H_OFFSET 5 +#define FTS_TOUCH_Y_L_OFFSET 6 +#define FTS_TOUCH_PRESSURE_OFFSET 7 +#define FTS_TOUCH_AREA_OFFSET 8 +#define FTS_TOUCH_TYPE_OFFSET 3 +#define FTS_TOUCH_ID_OFFSET 5 + +#define FTS_TOUCH_DOWN 0 +#define FTS_TOUCH_UP 1 +#define FTS_TOUCH_CONTACT 2 + +#define FTS_INTERVAL_READ_REG_MS 100 +#define FTS_TIMEOUT_READ_REG_MS 2000 + +#define FTS_DRIVER_NAME "fts-i2c" + +static const u16 fts_chip_types[] = { + 0x5452, + 0x8719, +}; + +struct fts_ts_data { + struct i2c_client *client; + struct input_dev *input_dev; + struct regmap *regmap; + int irq; + struct regulator_bulk_data regulators[2]; + u8 max_touch_points; + u8 *point_buf; + int point_buf_size; + struct gpio_desc *reset_gpio; + struct touchscreen_properties prop; +}; + +struct fts_i2c_chip_data { + int max_touch_points; +}; + +int fts_check_status(struct fts_ts_data *data) +{ + int error, i = 0, count = 0; + unsigned int val, id; + + do { + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_L, &id); + if (error) + dev_err(&data->client->dev, "I2C read failed: %d\n", error); + + error = regmap_read(data->regmap, FTS_REG_CHIP_ID_H, &val); + if (error) + dev_err(&data->client->dev, "I2C read failed: %d\n", error); + + id |= val << 8; + + for (i = 0; i < ARRAY_SIZE(fts_chip_types); i++) + if (id == fts_chip_types[i]) + return 0; + + count++; + msleep(FTS_INTERVAL_READ_REG_MS); + } while ((count * FTS_INTERVAL_READ_REG_MS) < FTS_TIMEOUT_READ_REG_MS); + + return -EIO; +} + +static int fts_report_touch(struct fts_ts_data *data) +{ + struct input_dev *input_dev = data->input_dev; + int base; + unsigned int x, y, z, maj; + u8 slot, type; + int error, i = 0; + + u8 *buf = data->point_buf; + + memset(buf, 0, data->point_buf_size); + + error = regmap_bulk_read(data->regmap, 0, buf, data->point_buf_size); + if (error) { + dev_err(&data->client->dev, "I2C read failed: %d\n", error); + return error; + } + + for (i = 0; i < data->max_touch_points; i++) { + base = FTS_ONE_TOUCH_LEN * i; + + slot = buf[base + FTS_TOUCH_ID_OFFSET] >> 4; + if (slot >= data->max_touch_points) + break; + + x = ((buf[base + FTS_TOUCH_X_H_OFFSET] & 0x0F) << 8) + + (buf[base + FTS_TOUCH_X_L_OFFSET] & 0xFF); + y = ((buf[base + FTS_TOUCH_Y_H_OFFSET] & 0x0F) << 8) + + (buf[base + FTS_TOUCH_Y_L_OFFSET] & 0xFF); + + z = buf[base + FTS_TOUCH_PRESSURE_OFFSET]; + if (z == 0) + z = 0x3f; + + maj = buf[base + FTS_TOUCH_AREA_OFFSET] >> 4; + if (maj == 0) + maj = 0x09; + + type = buf[base + FTS_TOUCH_TYPE_OFFSET] >> 6; + + input_mt_slot(input_dev, slot); + if (type == FTS_TOUCH_DOWN || type == FTS_TOUCH_CONTACT) { + input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, true); + touchscreen_report_pos(data->input_dev, &data->prop, x, y, true); + input_report_abs(input_dev, ABS_MT_PRESSURE, z); + input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, maj); + input_report_key(data->input_dev, BTN_TOUCH, 1); + } else { + input_report_key(data->input_dev, BTN_TOUCH, 0); + input_mt_report_slot_inactive(input_dev); + } + } + input_mt_sync_frame(input_dev); + input_sync(input_dev); + + return 0; +} + +static irqreturn_t fts_ts_interrupt(int irq, void *dev_id) +{ + struct fts_ts_data *data = dev_id; + + return fts_report_touch(data) ? IRQ_NONE : IRQ_HANDLED; +} + +static void fts_power_off(void *d) +{ + struct fts_ts_data *data = d; + + regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators); +} + +static int fts_start(struct fts_ts_data *data) +{ + int error; + + error = regulator_bulk_enable(ARRAY_SIZE(data->regulators), + data->regulators); + if (error) { + dev_err(&data->client->dev, "failed to enable regulators\n"); + return error; + } + + gpiod_set_value_cansleep(data->reset_gpio, 0); + msleep(200); + + enable_irq(data->irq); + + return 0; +} + +static int fts_stop(struct fts_ts_data *data) +{ + disable_irq(data->irq); + gpiod_set_value_cansleep(data->reset_gpio, 1); + fts_power_off(data); + + return 0; +} + +static int fts_input_open(struct input_dev *dev) +{ + struct fts_ts_data *data = input_get_drvdata(dev); + int error; + + error = fts_start(data); + if (error) + return error; + + error = fts_check_status(data); + if (error) { + dev_err(&data->client->dev, "Failed to start or unsupported chip"); + return error; + } + + return 0; +} + +static void fts_input_close(struct input_dev *dev) +{ + struct fts_ts_data *data = input_get_drvdata(dev); + + fts_stop(data); +} + +static int fts_input_init(struct fts_ts_data *data) +{ + struct device *dev = &data->client->dev; + struct input_dev *input_dev; + int error = 0; + + input_dev = devm_input_allocate_device(dev); + if (!input_dev) + return -ENOMEM; + + data->input_dev = input_dev; + + input_dev->name = FTS_DRIVER_NAME; + input_dev->id.bustype = BUS_I2C; + input_dev->dev.parent = dev; + input_dev->open = fts_input_open; + input_dev->close = fts_input_close; + input_set_drvdata(input_dev, data); + + input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X); + input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y); + input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0); + input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0); + + touchscreen_parse_properties(input_dev, true, &data->prop); + if (!data->prop.max_x || !data->prop.max_y) { + dev_err(dev, + "touchscreen-size-x and/or touchscreen-size-y not set in device properties\n"); + return -EINVAL; + } + + error = input_mt_init_slots(input_dev, data->max_touch_points, + INPUT_MT_DIRECT); + if (error) + return error; + + data->point_buf_size = (data->max_touch_points * FTS_ONE_TOUCH_LEN) + 3; + data->point_buf = devm_kzalloc(dev, data->point_buf_size, GFP_KERNEL); + if (!data->point_buf) + return -ENOMEM; + + error = input_register_device(input_dev); + if (error) { + dev_err(dev, "Failed to register input device\n"); + return error; + } + + return 0; +} + +static const struct regmap_config fts_ts_i2c_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static int fts_ts_probe(struct i2c_client *client) +{ + const struct i2c_device_id *id = i2c_client_get_device_id(client); + const struct fts_i2c_chip_data *chip_data; + struct fts_ts_data *data; + int error = 0; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "I2C not supported"); + return -ENODEV; + } + + if (!client->irq) { + dev_err(&client->dev, "No irq specified\n"); + return -EINVAL; + } + + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + chip_data = device_get_match_data(&client->dev); + if (!chip_data) + chip_data = (const struct fts_i2c_chip_data *)id->driver_data; + if (!chip_data || !chip_data->max_touch_points) { + dev_err(&client->dev, "invalid or missing chip data\n"); + return -EINVAL; + } + if (chip_data->max_touch_points > FTS_MAX_POINTS_SUPPORT) { + dev_err(&client->dev, + "invalid chip data, max_touch_points should be less than or equal to %d\n", + FTS_MAX_POINTS_SUPPORT); + return -EINVAL; + } + data->max_touch_points = chip_data->max_touch_points; + + data->client = client; + i2c_set_clientdata(client, data); + + data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(data->reset_gpio)) { + error = PTR_ERR(data->reset_gpio); + dev_err(&client->dev, "Failed to request reset gpio, error %d\n", error); + return error; + } + + data->regmap = devm_regmap_init_i2c(client, &fts_ts_i2c_regmap_config); + if (IS_ERR(data->regmap)) { + error = PTR_ERR(data->regmap); + dev_err(&client->dev, "regmap allocation failed, error %d\n", error); + return error; + } + + /* + * AVDD is the analog voltage supply (2.6V to 3.3V) + * VDDIO is the digital voltage supply (1.8V) + */ + data->regulators[0].supply = "avdd"; + data->regulators[1].supply = "vddio"; + error = devm_regulator_bulk_get(&client->dev, ARRAY_SIZE(data->regulators), + data->regulators); + if (error) { + dev_err(&client->dev, "Failed to get regulators %d\n", error); + return error; + } + + error = devm_add_action_or_reset(&client->dev, fts_power_off, data); + if (error) { + dev_err(&client->dev, "failed to install power off handler\n"); + return error; + } + + error = devm_request_threaded_irq(&client->dev, client->irq, NULL, + fts_ts_interrupt, IRQF_ONESHOT, + client->name, data); + if (error) { + dev_err(&client->dev, "Failed to request IRQ: %d\n", error); + return error; + } + + error = fts_input_init(data); + if (error) + return error; + + return 0; +} + +static int fts_pm_suspend(struct device *dev) +{ + struct fts_ts_data *data = dev_get_drvdata(dev); + + mutex_lock(&data->input_dev->mutex); + + if (input_device_enabled(data->input_dev)) + fts_stop(data); + + mutex_unlock(&data->input_dev->mutex); + + return 0; +} + +static int fts_pm_resume(struct device *dev) +{ + struct fts_ts_data *data = dev_get_drvdata(dev); + int error = 0; + + mutex_lock(&data->input_dev->mutex); + + if (input_device_enabled(data->input_dev)) + error = fts_start(data); + + mutex_unlock(&data->input_dev->mutex); + + return error; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(fts_dev_pm_ops, fts_pm_suspend, fts_pm_resume); + +static const struct fts_i2c_chip_data fts5452_chip_data = { + .max_touch_points = 5, +}; + +static const struct fts_i2c_chip_data fts8719_chip_data = { + .max_touch_points = 10, +}; + +static const struct i2c_device_id fts_i2c_id[] = { + { .name = "fts5452", .driver_data = (long)&fts5452_chip_data }, + { .name = "fts8719", .driver_data = (long)&fts8719_chip_data }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(i2c, fts_i2c_id); + +static const struct of_device_id fts_of_match[] = { + { .compatible = "focaltech,fts5452", .data = &fts5452_chip_data }, + { .compatible = "focaltech,fts8719", .data = &fts8719_chip_data }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, fts_of_match); + +static struct i2c_driver fts_ts_driver = { + .probe_new = fts_ts_probe, + .id_table = fts_i2c_id, + .driver = { + .name = FTS_DRIVER_NAME, + .pm = pm_sleep_ptr(&fts_dev_pm_ops), + .of_match_table = fts_of_match, + }, +}; +module_i2c_driver(fts_ts_driver); + +MODULE_AUTHOR("Joel Selvaraj <joelselvaraj.oss@gmail.com>"); +MODULE_AUTHOR("Caleb Connolly <caleb@connolly.tech>"); +MODULE_DESCRIPTION("Focaltech Touchscreen Driver"); +MODULE_LICENSE("GPL");