Add support for Imagis touchscreens, used on various mobile
devices such as Samsung Galaxy J5 (2015), J3 (2015), J5 (2016).
v2: rebase on top of the correct tree
v3:
- prefix all defines as IST3038C
- use two tabs for all defines
- add missing <linux/regulator/consumer.h> header
- drop ADDR_LEN and DATA_LEN defines; use sizeof(reg_be) instead
- use __be32 type for reg_be
- add a comment about i2c read not being successful on first try
- use "ret" instead of "res" in read_reg function
- don't use the internal __cpu_to_be32 function, use cpu_to_be32 instead
- use "error" instead of "ret" in interrupt handler
- pass the slot state directly, without ternary operator
- drop the dev_err in init_input_dev function
- reorder the functions in _probe so that the chipid command is read as fast
as possible
- don't use imagis_start in probe
- initialize the irq after the chip is powered
- save the return value in imagis_resume
- drop WIDTH_MAJOR since only TOUCH_MAJOR is reported
- the "chip detected" message is now dev_dbg
- reorder headers so they are in alphabetic order
- use GENMASK to generate masks for getting the X and Y coordinates and touch area
- drop *_pressure from device tree bindings since the driver doesn't
support reporting pressure
- fix the typo with i2c address in device treee bindings (48 instead of 50)
- add IRQF_NO_AUTOEN flag to avoid unbalanced irq enable
v4:
- alphabetically order MAINTAINERS entry
- alphabetically order Kconfig and Makefile
- drop the error message in init_regulators
- disable regulators on probe error
- drop IRQF_TRIGGER_FALLING
- @ is not optional (device tree bindings)
- don't use items for compatible
- add maxItems property to reg, drop the comment
v5:
- compatible enum is not an item of the list, drop "-"
v6:
- add _MS suffix to the delay define, drop the comment
- change the reason for retry comment
- add imagis_power_off and imagis_power_on functions to turn regulators
on and off
- use imagis_power_on/off in imagis_start and imagis_stop as well as in probe function
- use error instead of ret in calls to functions which only return 0 or -errno
- include linux/bits.h
- proper indentation in Kconfig
- drop the dev_dbg chip id message
- MODULE_DEVICE_TABLE(of, ...);
- no extra tabs in i2c_driver struct
- save the return value in imagis_suspend
v7:
- initialize ret with 0 in _suspend and _resume (kernel test robot)
- use a separate ret_be variable to avoid casting to __be32 (kernel test robot)
Markuss Broks (2):
dt-bindings: input/touchscreen: bindings for Imagis
Input: add Imagis touchscreen driver
.../input/touchscreen/imagis,ist3038c.yaml | 78 +++++
.../devicetree/bindings/vendor-prefixes.yaml | 2 +
MAINTAINERS | 6 +
drivers/input/touchscreen/Kconfig | 10 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/imagis.c | 329 ++++++++++++++++++
6 files changed, 426 insertions(+)
create mode 100644 Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
create mode 100644 drivers/input/touchscreen/imagis.c
--
2.35.0
This patch adds device-tree bindings for the Imagis
IST3038C touch screen IC.
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Acked-by: Rob Herring <[email protected]>
Signed-off-by: Markuss Broks <[email protected]>
---
.../input/touchscreen/imagis,ist3038c.yaml | 74 +++++++++++++++++++
.../devicetree/bindings/vendor-prefixes.yaml | 2 +
2 files changed, 76 insertions(+)
create mode 100644 Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
diff --git a/Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml b/Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
new file mode 100644
index 000000000000..e3a2b871e50c
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/touchscreen/imagis,ist3038c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Imagis IST30XXC family touchscreen controller bindings
+
+maintainers:
+ - Markuss Broks <[email protected]>
+
+allOf:
+ - $ref: touchscreen.yaml#
+
+properties:
+ $nodename:
+ pattern: "^touchscreen@[0-9a-f]+$"
+
+ compatible:
+ enum:
+ - imagis,ist3038c
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ vdd-supply:
+ description: Power supply regulator for the chip
+
+ vddio-supply:
+ description: Power supply regulator for the I2C bus
+
+ touchscreen-size-x: true
+ touchscreen-size-y: true
+ touchscreen-fuzz-x: true
+ touchscreen-fuzz-y: true
+ touchscreen-inverted-x: true
+ touchscreen-inverted-y: true
+ touchscreen-swapped-x-y: true
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - touchscreen-size-x
+ - touchscreen-size-y
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ touchscreen@50 {
+ compatible = "imagis,ist3038c";
+ reg = <0x50>;
+ interrupt-parent = <&gpio>;
+ interrupts = <13 IRQ_TYPE_EDGE_FALLING>;
+ vdd-supply = <&ldo1_reg>;
+ vddio-supply = <&ldo2_reg>;
+ touchscreen-size-x = <720>;
+ touchscreen-size-y = <1280>;
+ touchscreen-fuzz-x = <10>;
+ touchscreen-fuzz-y = <10>;
+ touchscreen-inverted-x;
+ touchscreen-inverted-y;
+ };
+ };
+
+...
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index cdc851e275f1..9357cdc5aef5 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -551,6 +551,8 @@ patternProperties:
description: Ingenieurburo Fur Ic-Technologie (I/F/I)
"^ilitek,.*":
description: ILI Technology Corporation (ILITEK)
+ "^imagis,.*":
+ description: Imagis Technologies Co., Ltd.
"^img,.*":
description: Imagination Technologies Ltd.
"^imi,.*":
--
2.35.0
Add support for the IST3038C touchscreen IC from Imagis, based on
downstream driver. The driver supports multi-touch (10 touch points)
The IST3038C IC supports touch keys, but the support isn't added
because the touch screen used for testing doesn't utilize touch keys.
Looking at the downstream driver, it is possible to add support
for other Imagis ICs of IST30**C series.
Signed-off-by: Markuss Broks <[email protected]>
---
MAINTAINERS | 6 +
drivers/input/touchscreen/Kconfig | 10 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/imagis.c | 348 +++++++++++++++++++++++++++++
4 files changed, 365 insertions(+)
create mode 100644 drivers/input/touchscreen/imagis.c
diff --git a/MAINTAINERS b/MAINTAINERS
index a899828a8d4e..3b99c60e9f4b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9411,6 +9411,12 @@ M: Stanislaw Gruszka <[email protected]>
S: Maintained
F: drivers/usb/atm/ueagle-atm.c
+IMAGIS TOUCHSCREEN DRIVER
+M: Markuss Broks <[email protected]>
+S: Maintained
+F: Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
+F: drivers/input/touchscreen/imagis.c
+
IMGTEC ASCII LCD DRIVER
M: Paul Burton <[email protected]>
S: Maintained
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 2f6adfb7b938..f1414f0ad7af 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -638,6 +638,16 @@ config TOUCHSCREEN_MTOUCH
To compile this driver as a module, choose M here: the
module will be called mtouch.
+config TOUCHSCREEN_IMAGIS
+ tristate "Imagis touchscreen support"
+ depends on I2C
+ help
+ Say Y here if you have an Imagis IST30xxC touchscreen.
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called imagis.
+
config TOUCHSCREEN_IMX6UL_TSC
tristate "Freescale i.MX6UL touchscreen controller"
depends on ((OF && GPIOLIB) || COMPILE_TEST) && HAS_IOMEM
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 39a8127cf6a5..557f84fd2075 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o
obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o
obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o
obj-$(CONFIG_TOUCHSCREEN_ILITEK) += ilitek_ts_i2c.o
+obj-$(CONFIG_TOUCHSCREEN_IMAGIS) += imagis.o
obj-$(CONFIG_TOUCHSCREEN_IMX6UL_TSC) += imx6ul_tsc.o
obj-$(CONFIG_TOUCHSCREEN_INEXIO) += inexio.o
obj-$(CONFIG_TOUCHSCREEN_IPROC) += bcm_iproc_tsc.o
diff --git a/drivers/input/touchscreen/imagis.c b/drivers/input/touchscreen/imagis.c
new file mode 100644
index 000000000000..5117d8674d82
--- /dev/null
+++ b/drivers/input/touchscreen/imagis.c
@@ -0,0 +1,348 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regulator/consumer.h>
+
+#define IST3038C_HIB_ACCESS (0x800B << 16)
+#define IST3038C_DIRECT_ACCESS BIT(31)
+#define IST3038C_REG_CHIPID 0x40001000
+#define IST3038C_REG_HIB_BASE 0x30000100
+#define IST3038C_REG_TOUCH_STATUS (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS)
+#define IST3038C_REG_TOUCH_COORD (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS | 0x8)
+#define IST3038C_REG_INTR_MESSAGE (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS | 0x4)
+#define IST3038C_WHOAMI 0x38c
+#define IST3038C_CHIP_ON_DELAY_MS 60
+#define IST3038C_I2C_RETRY_COUNT 3
+#define IST3038C_MAX_SUPPORTED_FINGER_NUM 10
+#define IST3038C_X_MASK GENMASK(23, 12)
+#define IST3038C_X_SHIFT 12
+#define IST3038C_Y_MASK GENMASK(11, 0)
+#define IST3038C_AREA_MASK GENMASK(27, 24)
+#define IST3038C_AREA_SHIFT 24
+#define IST3038C_FINGER_COUNT_MASK GENMASK(15, 12)
+#define IST3038C_FINGER_COUNT_SHIFT 12
+#define IST3038C_FINGER_STATUS_MASK GENMASK(9, 0)
+
+struct imagis_ts {
+ struct i2c_client *client;
+ struct input_dev *input_dev;
+ struct touchscreen_properties prop;
+ struct regulator_bulk_data supplies[2];
+};
+
+static int imagis_i2c_read_reg(struct imagis_ts *ts,
+ unsigned int reg, unsigned int *buffer)
+{
+ __be32 ret_be;
+ __be32 reg_be = cpu_to_be32(reg);
+ struct i2c_msg msg[] = {
+ {
+ .addr = ts->client->addr,
+ .flags = 0,
+ .buf = (unsigned char *)®_be,
+ .len = sizeof(reg_be),
+ }, {
+ .addr = ts->client->addr,
+ .flags = I2C_M_RD,
+ .buf = (unsigned char *)&ret_be,
+ .len = sizeof(ret_be),
+ },
+ };
+ int ret, error;
+ int retry = IST3038C_I2C_RETRY_COUNT;
+
+ /* Retry in case the controller fails to respond */
+ do {
+ ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
+ if (ret == ARRAY_SIZE(msg)) {
+ *buffer = be32_to_cpu(ret_be);
+ return 0;
+ }
+
+ error = ret < 0 ? ret : -EIO;
+ dev_err(&ts->client->dev,
+ "%s - i2c_transfer failed: %d (%d)\n",
+ __func__, error, ret);
+ } while (--retry);
+
+ return error;
+}
+
+static irqreturn_t imagis_interrupt(int irq, void *dev_id)
+{
+ struct imagis_ts *ts = dev_id;
+ unsigned int finger_status, intr_message;
+ int error, i, finger_count, finger_pressed;
+
+ error = imagis_i2c_read_reg(ts, IST3038C_REG_INTR_MESSAGE, &intr_message);
+ if (error) {
+ dev_err(&ts->client->dev, "failed to read the interrupt message\n");
+ return IRQ_HANDLED;
+ }
+
+ finger_count = (intr_message & IST3038C_FINGER_COUNT_MASK) >> IST3038C_FINGER_COUNT_SHIFT;
+ finger_pressed = intr_message & IST3038C_FINGER_STATUS_MASK;
+ if (finger_count > IST3038C_MAX_SUPPORTED_FINGER_NUM) {
+ dev_err(&ts->client->dev, "finger count is more than maximum supported\n");
+ return IRQ_HANDLED;
+ }
+
+ for (i = 0; i < finger_count; i++) {
+ error = imagis_i2c_read_reg(ts, IST3038C_REG_TOUCH_COORD + (i * 4), &finger_status);
+ if (error) {
+ dev_err(&ts->client->dev, "failed to read coordinates for finger %d\n", i);
+ return IRQ_HANDLED;
+ }
+ input_mt_slot(ts->input_dev, i);
+ input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER,
+ finger_pressed & BIT(i));
+ touchscreen_report_pos(ts->input_dev, &ts->prop,
+ (finger_status & IST3038C_X_MASK) >> IST3038C_X_SHIFT,
+ finger_status & IST3038C_Y_MASK, 1);
+ input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR,
+ (finger_status & IST3038C_AREA_MASK) >> IST3038C_AREA_SHIFT);
+ }
+ input_mt_sync_frame(ts->input_dev);
+ input_sync(ts->input_dev);
+
+ return IRQ_HANDLED;
+}
+
+static int imagis_power_off(struct imagis_ts *ts)
+{
+ int error;
+
+ error = regulator_bulk_disable(ARRAY_SIZE(ts->supplies),
+ ts->supplies);
+ if (error)
+ dev_err(&ts->client->dev,
+ "Failed to disable regulators: %d\n", error);
+ return error;
+}
+
+static int imagis_power_on(struct imagis_ts *ts)
+{
+ int error;
+
+ error = regulator_bulk_enable(ARRAY_SIZE(ts->supplies),
+ ts->supplies);
+ if (error)
+ dev_err(&ts->client->dev,
+ "Failed to enable regulators: %d\n", error);
+ return error;
+}
+
+static int imagis_start(struct imagis_ts *ts)
+{
+ int error;
+
+ error = imagis_power_on(ts);
+ if (error)
+ return error;
+
+ msleep(IST3038C_CHIP_ON_DELAY_MS);
+
+ enable_irq(ts->client->irq);
+ return error;
+}
+
+static int imagis_stop(struct imagis_ts *ts)
+{
+ disable_irq(ts->client->irq);
+
+ return imagis_power_off(ts);
+}
+
+static int imagis_input_open(struct input_dev *dev)
+{
+ struct imagis_ts *ts = input_get_drvdata(dev);
+
+ return imagis_start(ts);
+}
+
+static void imagis_input_close(struct input_dev *dev)
+{
+ struct imagis_ts *ts = input_get_drvdata(dev);
+
+ imagis_stop(ts);
+}
+
+static int imagis_init_input_dev(struct imagis_ts *ts)
+{
+ struct input_dev *input_dev;
+ int error;
+
+ input_dev = devm_input_allocate_device(&ts->client->dev);
+ if (!input_dev)
+ return -ENOMEM;
+
+ ts->input_dev = input_dev;
+
+ input_dev->name = "Imagis capacitive touchscreen";
+ input_dev->phys = "input/ts";
+ input_dev->id.bustype = BUS_I2C;
+ input_dev->open = imagis_input_open;
+ input_dev->close = imagis_input_close;
+
+ input_set_drvdata(input_dev, ts);
+
+ 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);
+
+ touchscreen_parse_properties(input_dev, true, &ts->prop);
+ if (!ts->prop.max_x || !ts->prop.max_y) {
+ dev_err(&ts->client->dev,
+ "Touchscreen-size-x and/or touchscreen-size-y not set in dts\n");
+ return -EINVAL;
+ }
+
+ error = input_mt_init_slots(input_dev, IST3038C_MAX_SUPPORTED_FINGER_NUM,
+ INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+ if (error) {
+ dev_err(&ts->client->dev,
+ "Failed to initialize MT slots: %d", error);
+ return error;
+ }
+
+ error = input_register_device(input_dev);
+ if (error) {
+ dev_err(&ts->client->dev,
+ "Failed to register input device: %d", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static int imagis_init_regulators(struct imagis_ts *ts)
+{
+ struct i2c_client *client = ts->client;
+ int error = 0;
+
+ ts->supplies[0].supply = "vdd";
+ ts->supplies[1].supply = "vddio";
+ error = devm_regulator_bulk_get(&client->dev,
+ ARRAY_SIZE(ts->supplies),
+ ts->supplies);
+
+ return error;
+}
+
+static int imagis_probe(struct i2c_client *i2c)
+{
+ struct device *dev;
+ struct imagis_ts *ts;
+ int chip_id, ret, error;
+
+ dev = &i2c->dev;
+
+ ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ ts->client = i2c;
+
+ error = imagis_init_regulators(ts);
+ if (error)
+ return dev_err_probe(dev, error, "regulator init error: %d\n", error);
+
+ error = imagis_power_on(ts);
+ if (error)
+ return dev_err_probe(dev, error, "failed to enable regulators: %d\n", error);
+
+ msleep(IST3038C_CHIP_ON_DELAY_MS);
+
+ ret = imagis_i2c_read_reg(ts, IST3038C_REG_CHIPID | IST3038C_DIRECT_ACCESS, &chip_id);
+ if (ret) {
+ imagis_power_off(ts);
+ return dev_err_probe(dev, error, "chip ID read failure: %d\n", ret);
+ }
+
+ if (chip_id != IST3038C_WHOAMI) {
+ imagis_power_off(ts);
+ return dev_err_probe(dev, -EINVAL, "unknown chip ID: 0x%x\n", chip_id);
+ }
+
+ error = devm_request_threaded_irq(dev, i2c->irq,
+ NULL, imagis_interrupt,
+ IRQF_ONESHOT | IRQF_NO_AUTOEN,
+ "imagis-touchscreen", ts);
+ if (error) {
+ imagis_power_off(ts);
+ return dev_err_probe(dev, error, "IRQ allocation failure: %d\n", error);
+ }
+
+ error = imagis_init_input_dev(ts);
+ if (error) {
+ imagis_power_off(ts);
+ return dev_err_probe(dev, error, "input subsystem init error: %d\n", error);
+ }
+
+ return 0;
+}
+
+static int __maybe_unused imagis_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct imagis_ts *ts = i2c_get_clientdata(client);
+ int ret = 0;
+
+ mutex_lock(&ts->input_dev->mutex);
+
+ if (input_device_enabled(ts->input_dev))
+ ret = imagis_stop(ts);
+
+ mutex_unlock(&ts->input_dev->mutex);
+
+ return ret;
+}
+
+static int __maybe_unused imagis_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct imagis_ts *ts = i2c_get_clientdata(client);
+ int ret = 0;
+
+ mutex_lock(&ts->input_dev->mutex);
+
+ if (input_device_enabled(ts->input_dev))
+ ret = imagis_start(ts);
+
+ mutex_unlock(&ts->input_dev->mutex);
+
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(imagis_pm_ops, imagis_suspend, imagis_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id imagis_of_match[] = {
+ { .compatible = "imagis,ist3038c", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, imagis_of_match);
+#endif
+
+static struct i2c_driver imagis_ts_driver = {
+ .driver = {
+ .name = "imagis-touchscreen",
+ .pm = &imagis_pm_ops,
+ .of_match_table = of_match_ptr(imagis_of_match),
+ },
+ .probe_new = imagis_probe,
+};
+
+module_i2c_driver(imagis_ts_driver);
+
+MODULE_DESCRIPTION("Imagis IST3038C Touchscreen Driver");
+MODULE_AUTHOR("Markuss Broks <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.35.0
Hi Markuss,
On Wed, Feb 23, 2022 at 06:07:41PM +0200, Markuss Broks wrote:
> Add support for the IST3038C touchscreen IC from Imagis, based on
> downstream driver. The driver supports multi-touch (10 touch points)
> The IST3038C IC supports touch keys, but the support isn't added
> because the touch screen used for testing doesn't utilize touch keys.
> Looking at the downstream driver, it is possible to add support
> for other Imagis ICs of IST30**C series.
>
> Signed-off-by: Markuss Broks <[email protected]>
> ---
> MAINTAINERS | 6 +
> drivers/input/touchscreen/Kconfig | 10 +
> drivers/input/touchscreen/Makefile | 1 +
> drivers/input/touchscreen/imagis.c | 348 +++++++++++++++++++++++++++++
> 4 files changed, 365 insertions(+)
> create mode 100644 drivers/input/touchscreen/imagis.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a899828a8d4e..3b99c60e9f4b 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9411,6 +9411,12 @@ M: Stanislaw Gruszka <[email protected]>
> S: Maintained
> F: drivers/usb/atm/ueagle-atm.c
>
> +IMAGIS TOUCHSCREEN DRIVER
> +M: Markuss Broks <[email protected]>
> +S: Maintained
> +F: Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
> +F: drivers/input/touchscreen/imagis.c
> +
> IMGTEC ASCII LCD DRIVER
> M: Paul Burton <[email protected]>
> S: Maintained
> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
> index 2f6adfb7b938..f1414f0ad7af 100644
> --- a/drivers/input/touchscreen/Kconfig
> +++ b/drivers/input/touchscreen/Kconfig
> @@ -638,6 +638,16 @@ config TOUCHSCREEN_MTOUCH
> To compile this driver as a module, choose M here: the
> module will be called mtouch.
>
> +config TOUCHSCREEN_IMAGIS
> + tristate "Imagis touchscreen support"
> + depends on I2C
> + help
> + Say Y here if you have an Imagis IST30xxC touchscreen.
> + If unsure, say N.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called imagis.
> +
> config TOUCHSCREEN_IMX6UL_TSC
> tristate "Freescale i.MX6UL touchscreen controller"
> depends on ((OF && GPIOLIB) || COMPILE_TEST) && HAS_IOMEM
> diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
> index 39a8127cf6a5..557f84fd2075 100644
> --- a/drivers/input/touchscreen/Makefile
> +++ b/drivers/input/touchscreen/Makefile
> @@ -49,6 +49,7 @@ obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o
> obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o
> obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o
> obj-$(CONFIG_TOUCHSCREEN_ILITEK) += ilitek_ts_i2c.o
> +obj-$(CONFIG_TOUCHSCREEN_IMAGIS) += imagis.o
> obj-$(CONFIG_TOUCHSCREEN_IMX6UL_TSC) += imx6ul_tsc.o
> obj-$(CONFIG_TOUCHSCREEN_INEXIO) += inexio.o
> obj-$(CONFIG_TOUCHSCREEN_IPROC) += bcm_iproc_tsc.o
> diff --git a/drivers/input/touchscreen/imagis.c b/drivers/input/touchscreen/imagis.c
> new file mode 100644
> index 000000000000..5117d8674d82
> --- /dev/null
> +++ b/drivers/input/touchscreen/imagis.c
> @@ -0,0 +1,348 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <linux/bits.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/input.h>
> +#include <linux/input/mt.h>
> +#include <linux/input/touchscreen.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/property.h>
> +#include <linux/regulator/consumer.h>
> +
> +#define IST3038C_HIB_ACCESS (0x800B << 16)
> +#define IST3038C_DIRECT_ACCESS BIT(31)
> +#define IST3038C_REG_CHIPID 0x40001000
> +#define IST3038C_REG_HIB_BASE 0x30000100
> +#define IST3038C_REG_TOUCH_STATUS (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS)
> +#define IST3038C_REG_TOUCH_COORD (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS | 0x8)
> +#define IST3038C_REG_INTR_MESSAGE (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS | 0x4)
> +#define IST3038C_WHOAMI 0x38c
> +#define IST3038C_CHIP_ON_DELAY_MS 60
> +#define IST3038C_I2C_RETRY_COUNT 3
> +#define IST3038C_MAX_SUPPORTED_FINGER_NUM 10
> +#define IST3038C_X_MASK GENMASK(23, 12)
> +#define IST3038C_X_SHIFT 12
> +#define IST3038C_Y_MASK GENMASK(11, 0)
> +#define IST3038C_AREA_MASK GENMASK(27, 24)
> +#define IST3038C_AREA_SHIFT 24
> +#define IST3038C_FINGER_COUNT_MASK GENMASK(15, 12)
> +#define IST3038C_FINGER_COUNT_SHIFT 12
> +#define IST3038C_FINGER_STATUS_MASK GENMASK(9, 0)
> +
> +struct imagis_ts {
> + struct i2c_client *client;
> + struct input_dev *input_dev;
> + struct touchscreen_properties prop;
> + struct regulator_bulk_data supplies[2];
> +};
> +
> +static int imagis_i2c_read_reg(struct imagis_ts *ts,
> + unsigned int reg, unsigned int *buffer)
> +{
> + __be32 ret_be;
> + __be32 reg_be = cpu_to_be32(reg);
> + struct i2c_msg msg[] = {
> + {
> + .addr = ts->client->addr,
> + .flags = 0,
> + .buf = (unsigned char *)®_be,
> + .len = sizeof(reg_be),
> + }, {
> + .addr = ts->client->addr,
> + .flags = I2C_M_RD,
> + .buf = (unsigned char *)&ret_be,
> + .len = sizeof(ret_be),
> + },
> + };
> + int ret, error;
> + int retry = IST3038C_I2C_RETRY_COUNT;
> +
> + /* Retry in case the controller fails to respond */
> + do {
> + ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
> + if (ret == ARRAY_SIZE(msg)) {
> + *buffer = be32_to_cpu(ret_be);
> + return 0;
> + }
> +
> + error = ret < 0 ? ret : -EIO;
> + dev_err(&ts->client->dev,
> + "%s - i2c_transfer failed: %d (%d)\n",
> + __func__, error, ret);
> + } while (--retry);
> +
> + return error;
> +}
> +
> +static irqreturn_t imagis_interrupt(int irq, void *dev_id)
> +{
> + struct imagis_ts *ts = dev_id;
> + unsigned int finger_status, intr_message;
> + int error, i, finger_count, finger_pressed;
> +
> + error = imagis_i2c_read_reg(ts, IST3038C_REG_INTR_MESSAGE, &intr_message);
> + if (error) {
> + dev_err(&ts->client->dev, "failed to read the interrupt message\n");
> + return IRQ_HANDLED;
> + }
> +
> + finger_count = (intr_message & IST3038C_FINGER_COUNT_MASK) >> IST3038C_FINGER_COUNT_SHIFT;
> + finger_pressed = intr_message & IST3038C_FINGER_STATUS_MASK;
> + if (finger_count > IST3038C_MAX_SUPPORTED_FINGER_NUM) {
> + dev_err(&ts->client->dev, "finger count is more than maximum supported\n");
> + return IRQ_HANDLED;
> + }
> +
> + for (i = 0; i < finger_count; i++) {
> + error = imagis_i2c_read_reg(ts, IST3038C_REG_TOUCH_COORD + (i * 4), &finger_status);
> + if (error) {
> + dev_err(&ts->client->dev, "failed to read coordinates for finger %d\n", i);
> + return IRQ_HANDLED;
> + }
> + input_mt_slot(ts->input_dev, i);
> + input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER,
> + finger_pressed & BIT(i));
> + touchscreen_report_pos(ts->input_dev, &ts->prop,
> + (finger_status & IST3038C_X_MASK) >> IST3038C_X_SHIFT,
> + finger_status & IST3038C_Y_MASK, 1);
> + input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR,
> + (finger_status & IST3038C_AREA_MASK) >> IST3038C_AREA_SHIFT);
> + }
> + input_mt_sync_frame(ts->input_dev);
> + input_sync(ts->input_dev);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int imagis_power_off(struct imagis_ts *ts)
> +{
> + int error;
> +
> + error = regulator_bulk_disable(ARRAY_SIZE(ts->supplies),
> + ts->supplies);
> + if (error)
> + dev_err(&ts->client->dev,
> + "Failed to disable regulators: %d\n", error);
> + return error;
> +}
> +
> +static int imagis_power_on(struct imagis_ts *ts)
> +{
> + int error;
> +
> + error = regulator_bulk_enable(ARRAY_SIZE(ts->supplies),
> + ts->supplies);
> + if (error)
> + dev_err(&ts->client->dev,
> + "Failed to enable regulators: %d\n", error);
> + return error;
> +}
> +
> +static int imagis_start(struct imagis_ts *ts)
> +{
> + int error;
> +
> + error = imagis_power_on(ts);
> + if (error)
> + return error;
> +
> + msleep(IST3038C_CHIP_ON_DELAY_MS);
> +
> + enable_irq(ts->client->irq);
> + return error;
> +}
> +
> +static int imagis_stop(struct imagis_ts *ts)
> +{
> + disable_irq(ts->client->irq);
> +
> + return imagis_power_off(ts);
> +}
> +
> +static int imagis_input_open(struct input_dev *dev)
> +{
> + struct imagis_ts *ts = input_get_drvdata(dev);
> +
> + return imagis_start(ts);
> +}
> +
> +static void imagis_input_close(struct input_dev *dev)
> +{
> + struct imagis_ts *ts = input_get_drvdata(dev);
> +
> + imagis_stop(ts);
> +}
> +
> +static int imagis_init_input_dev(struct imagis_ts *ts)
> +{
> + struct input_dev *input_dev;
> + int error;
> +
> + input_dev = devm_input_allocate_device(&ts->client->dev);
> + if (!input_dev)
> + return -ENOMEM;
> +
> + ts->input_dev = input_dev;
> +
> + input_dev->name = "Imagis capacitive touchscreen";
> + input_dev->phys = "input/ts";
> + input_dev->id.bustype = BUS_I2C;
> + input_dev->open = imagis_input_open;
> + input_dev->close = imagis_input_close;
> +
> + input_set_drvdata(input_dev, ts);
> +
> + 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);
> +
> + touchscreen_parse_properties(input_dev, true, &ts->prop);
> + if (!ts->prop.max_x || !ts->prop.max_y) {
> + dev_err(&ts->client->dev,
> + "Touchscreen-size-x and/or touchscreen-size-y not set in dts\n");
> + return -EINVAL;
> + }
> +
> + error = input_mt_init_slots(input_dev, IST3038C_MAX_SUPPORTED_FINGER_NUM,
> + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
> + if (error) {
> + dev_err(&ts->client->dev,
> + "Failed to initialize MT slots: %d", error);
> + return error;
> + }
> +
> + error = input_register_device(input_dev);
> + if (error) {
> + dev_err(&ts->client->dev,
> + "Failed to register input device: %d", error);
> + return error;
> + }
> +
> + return 0;
It is largely personal preference, but this is shorter:
error = input_register_device(...)
if (error)
dev_err(...)
return error;
I mention this because you use the same style elsewhere.
> +}
> +
> +static int imagis_init_regulators(struct imagis_ts *ts)
> +{
> + struct i2c_client *client = ts->client;
> + int error = 0;
This variable is not much use; you can simply return devm_regulator_bulk_get()
directly.
> +
> + ts->supplies[0].supply = "vdd";
> + ts->supplies[1].supply = "vddio";
> + error = devm_regulator_bulk_get(&client->dev,
> + ARRAY_SIZE(ts->supplies),
> + ts->supplies);
> +
> + return error;
> +}
> +
> +static int imagis_probe(struct i2c_client *i2c)
> +{
> + struct device *dev;
> + struct imagis_ts *ts;
> + int chip_id, ret, error;
> +
> + dev = &i2c->dev;
You can save this line by combining it with the definition of *dev above.
> +
> + ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
> + if (!ts)
> + return -ENOMEM;
> +
> + ts->client = i2c;
> +
> + error = imagis_init_regulators(ts);
> + if (error)
> + return dev_err_probe(dev, error, "regulator init error: %d\n", error);
> +
> + error = imagis_power_on(ts);
> + if (error)
> + return dev_err_probe(dev, error, "failed to enable regulators: %d\n", error);
As per my previous comments, you still seem to have unbalanced regulator
count because regulators are not turned back off after the driver is taken
down. You should add a device-managed action as with zet6223.c and other
drivers that do not implement a remove() callback.
If you do this, you do not need to call imagis_power_off() in each possible
error path as you have done below.
> +
> + msleep(IST3038C_CHIP_ON_DELAY_MS);
> +
> + ret = imagis_i2c_read_reg(ts, IST3038C_REG_CHIPID | IST3038C_DIRECT_ACCESS, &chip_id);
> + if (ret) {
> + imagis_power_off(ts);
> + return dev_err_probe(dev, error, "chip ID read failure: %d\n", ret);
> + }
Why to use 'ret' here and 'error' everywhere else? Please drop the former.
> +
> + if (chip_id != IST3038C_WHOAMI) {
> + imagis_power_off(ts);
> + return dev_err_probe(dev, -EINVAL, "unknown chip ID: 0x%x\n", chip_id);
> + }
> +
> + error = devm_request_threaded_irq(dev, i2c->irq,
> + NULL, imagis_interrupt,
> + IRQF_ONESHOT | IRQF_NO_AUTOEN,
> + "imagis-touchscreen", ts);
> + if (error) {
> + imagis_power_off(ts);
> + return dev_err_probe(dev, error, "IRQ allocation failure: %d\n", error);
> + }
> +
> + error = imagis_init_input_dev(ts);
> + if (error) {
> + imagis_power_off(ts);
> + return dev_err_probe(dev, error, "input subsystem init error: %d\n", error);
> + }
> +
> + return 0;
> +}
> +
> +static int __maybe_unused imagis_suspend(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct imagis_ts *ts = i2c_get_clientdata(client);
> + int ret = 0;
Again, please use 'error' here.
> +
> + mutex_lock(&ts->input_dev->mutex);
> +
> + if (input_device_enabled(ts->input_dev))
> + ret = imagis_stop(ts);
> +
> + mutex_unlock(&ts->input_dev->mutex);
> +
> + return ret;
> +}
> +
> +static int __maybe_unused imagis_resume(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct imagis_ts *ts = i2c_get_clientdata(client);
> + int ret = 0;
And here.
> +
> + mutex_lock(&ts->input_dev->mutex);
> +
> + if (input_device_enabled(ts->input_dev))
> + ret = imagis_start(ts);
> +
> + mutex_unlock(&ts->input_dev->mutex);
> +
> + return ret;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(imagis_pm_ops, imagis_suspend, imagis_resume);
> +
> +#ifdef CONFIG_OF
> +static const struct of_device_id imagis_of_match[] = {
> + { .compatible = "imagis,ist3038c", },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, imagis_of_match);
> +#endif
> +
> +static struct i2c_driver imagis_ts_driver = {
> + .driver = {
> + .name = "imagis-touchscreen",
> + .pm = &imagis_pm_ops,
> + .of_match_table = of_match_ptr(imagis_of_match),
> + },
> + .probe_new = imagis_probe,
> +};
> +
> +module_i2c_driver(imagis_ts_driver);
> +
> +MODULE_DESCRIPTION("Imagis IST3038C Touchscreen Driver");
> +MODULE_AUTHOR("Markuss Broks <[email protected]>");
> +MODULE_LICENSE("GPL");
> --
> 2.35.0
>
Kind regards,
Jeff LaBundy