Re: [PATCH 1/2] input: generalize the Imagis touchscreen driver
From: Markuss Broks
Date: Wed Sep 27 2023 - 11:39:10 EST
Hi Karel,
On 9/26/23 20:35, Karel Balej wrote:
This driver should work with other Imagis ICs of the IST30**C series.
Make that more apparent.
To be fair, this driver should work with all Imagis3 chips, which could
be a better name for it. However, I agree with Jeff here: the driver
doesn't necessarily need renaming.
Co-developed-by: Duje Mihanović<duje.mihanovic@xxxxxxxx>
Signed-off-by: Duje Mihanović<duje.mihanovic@xxxxxxxx>
Signed-off-by: Karel Balej<balejk@xxxxxxxxx>
---
...gis,ist3038c.yaml => imagis,ist30xxc.yaml} | 2 +-
MAINTAINERS | 2 +-
drivers/input/touchscreen/Kconfig | 4 +-
drivers/input/touchscreen/imagis.c | 86 +++++++++++--------
4 files changed, 52 insertions(+), 42 deletions(-)
rename Documentation/devicetree/bindings/input/touchscreen/{imagis,ist3038c.yaml => imagis,ist30xxc.yaml} (99%)
diff --git a/Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml b/Documentation/devicetree/bindings/input/touchscreen/imagis,ist30xxc.yaml
similarity index 99%
rename from Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
rename to Documentation/devicetree/bindings/input/touchscreen/imagis,ist30xxc.yaml
index 0d6b033fd5fb..09bf3a6acc5e 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
+++ b/Documentation/devicetree/bindings/input/touchscreen/imagis,ist30xxc.yaml
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
-$id:http://devicetree.org/schemas/input/touchscreen/imagis,ist3038c.yaml#
+$id:http://devicetree.org/schemas/input/touchscreen/imagis,ist30xxc.yaml#
$schema:http://devicetree.org/meta-schemas/core.yaml#
title: Imagis IST30XXC family touchscreen controller
diff --git a/MAINTAINERS b/MAINTAINERS
index b19995690904..b23e76418d94 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10209,7 +10209,7 @@ F: drivers/usb/atm/ueagle-atm.c
IMAGIS TOUCHSCREEN DRIVER
M: Markuss Broks<markuss.broks@xxxxxxxxx>
S: Maintained
-F: Documentation/devicetree/bindings/input/touchscreen/imagis,ist3038c.yaml
+F: Documentation/devicetree/bindings/input/touchscreen/imagis,ist30xxc.yaml
F: drivers/input/touchscreen/imagis.c
IMGTEC ASCII LCD DRIVER
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index e3e2324547b9..45503aa2653e 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -665,10 +665,10 @@ config TOUCHSCREEN_NOVATEK_NVT_TS
module will be called novatek-nvt-ts.
config TOUCHSCREEN_IMAGIS
- tristate "Imagis touchscreen support"
+ tristate "Imagis IST30XXC touchscreen support"
depends on I2C
help
- Say Y here if you have an Imagis IST30xxC touchscreen.
+ 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
diff --git a/drivers/input/touchscreen/imagis.c b/drivers/input/touchscreen/imagis.c
index 07111ca24455..4456f1b4d527 100644
--- a/drivers/input/touchscreen/imagis.c
+++ b/drivers/input/touchscreen/imagis.c
@@ -11,25 +11,26 @@
#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 IST30XXC_HIB_ACCESS (0x800B << 16)
+#define IST30XXC_DIRECT_ACCESS BIT(31)
+#define IST30XXC_REG_CHIPID 0x40001000
+#define IST30XXC_REG_HIB_BASE 0x30000100
+#define IST30XXC_REG_TOUCH_STATUS (IST30XXC_REG_HIB_BASE | IST30XXC_HIB_ACCESS)
+#define IST30XXC_REG_TOUCH_COORD (IST30XXC_REG_HIB_BASE | IST30XXC_HIB_ACCESS | 0x8)
+#define IST30XXC_REG_INTR_MESSAGE (IST30XXC_REG_HIB_BASE | IST30XXC_HIB_ACCESS | 0x4)
+#define IST30XXC_CHIP_ON_DELAY_MS 60
+#define IST30XXC_I2C_RETRY_COUNT 3
+#define IST30XXC_MAX_FINGER_NUM 10
+#define IST30XXC_X_MASK GENMASK(23, 12)
+#define IST30XXC_X_SHIFT 12
+#define IST30XXC_Y_MASK GENMASK(11, 0)
+#define IST30XXC_AREA_MASK GENMASK(27, 24)
+#define IST30XXC_AREA_SHIFT 24
+#define IST30XXC_FINGER_COUNT_MASK GENMASK(15, 12)
+#define IST30XXC_FINGER_COUNT_SHIFT 12
+#define IST30XXC_FINGER_STATUS_MASK GENMASK(9, 0)
+
#define IST3038C_WHOAMI 0x38c
-#define IST3038C_CHIP_ON_DELAY_MS 60
-#define IST3038C_I2C_RETRY_COUNT 3
-#define IST3038C_MAX_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;
@@ -57,7 +58,7 @@ static int imagis_i2c_read_reg(struct imagis_ts *ts,
},
};
int ret, error;
- int retry = IST3038C_I2C_RETRY_COUNT;
+ int retry = IST30XXC_I2C_RETRY_COUNT;
/* Retry in case the controller fails to respond */
do {
@@ -84,7 +85,7 @@ static irqreturn_t imagis_interrupt(int irq, void *dev_id)
int i;
int error;
- error = imagis_i2c_read_reg(ts, IST3038C_REG_INTR_MESSAGE,
+ error = imagis_i2c_read_reg(ts, IST30XXC_REG_INTR_MESSAGE,
&intr_message);
if (error) {
dev_err(&ts->client->dev,
@@ -92,20 +93,20 @@ static irqreturn_t imagis_interrupt(int irq, void *dev_id)
goto out;
}
- finger_count = (intr_message & IST3038C_FINGER_COUNT_MASK) >>
- IST3038C_FINGER_COUNT_SHIFT;
- if (finger_count > IST3038C_MAX_FINGER_NUM) {
+ finger_count = (intr_message & IST30XXC_FINGER_COUNT_MASK) >>
+ IST30XXC_FINGER_COUNT_SHIFT;
+ if (finger_count > IST30XXC_MAX_FINGER_NUM) {
dev_err(&ts->client->dev,
"finger count %d is more than maximum supported\n",
finger_count);
goto out;
}
- finger_pressed = intr_message & IST3038C_FINGER_STATUS_MASK;
+ finger_pressed = intr_message & IST30XXC_FINGER_STATUS_MASK;
for (i = 0; i < finger_count; i++) {
error = imagis_i2c_read_reg(ts,
- IST3038C_REG_TOUCH_COORD + (i * 4),
+ IST30XXC_REG_TOUCH_COORD + (i * 4),
&finger_status);
if (error) {
dev_err(&ts->client->dev,
@@ -118,12 +119,12 @@ static irqreturn_t imagis_interrupt(int irq, void *dev_id)
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);
+ (finger_status & IST30XXC_X_MASK) >>
+ IST30XXC_X_SHIFT,
+ finger_status & IST30XXC_Y_MASK, 1);
input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR,
- (finger_status & IST3038C_AREA_MASK) >>
- IST3038C_AREA_SHIFT);
+ (finger_status & IST30XXC_AREA_MASK) >>
+ IST30XXC_AREA_SHIFT);
}
input_mt_sync_frame(ts->input_dev);
@@ -148,7 +149,7 @@ static int imagis_power_on(struct imagis_ts *ts)
if (error)
return error;
- msleep(IST3038C_CHIP_ON_DELAY_MS);
+ msleep(IST30XXC_CHIP_ON_DELAY_MS);
return 0;
}
@@ -220,7 +221,7 @@ static int imagis_init_input_dev(struct imagis_ts *ts)
}
error = input_mt_init_slots(input_dev,
- IST3038C_MAX_FINGER_NUM,
+ IST30XXC_MAX_FINGER_NUM,
INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
if (error) {
dev_err(&ts->client->dev,
@@ -253,7 +254,7 @@ static int imagis_probe(struct i2c_client *i2c)
{
struct device *dev = &i2c->dev;
struct imagis_ts *ts;
- int chip_id, error;
+ int chip_id, dt_chip_id, error;
ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
if (!ts)
@@ -261,6 +262,8 @@ static int imagis_probe(struct i2c_client *i2c)
ts->client = i2c;
+ dt_chip_id = (int)(uintptr_t)device_get_match_data(&i2c->dev);
+
error = imagis_init_regulators(ts);
if (error) {
dev_err(dev, "regulator init error: %d\n", error);
@@ -280,15 +283,15 @@ static int imagis_probe(struct i2c_client *i2c)
}
error = imagis_i2c_read_reg(ts,
- IST3038C_REG_CHIPID | IST3038C_DIRECT_ACCESS,
+ IST30XXC_REG_CHIPID | IST30XXC_DIRECT_ACCESS,
&chip_id);
if (error) {
dev_err(dev, "chip ID read failure: %d\n", error);
return error;
}
- if (chip_id != IST3038C_WHOAMI) {
- dev_err(dev, "unknown chip ID: 0x%x\n", chip_id);
+ if (chip_id != dt_chip_id) {
+ dev_err(dev, "unknown or misconfigured chip ID: 0x%x\n", chip_id);
return -EINVAL;
}
@@ -345,12 +348,18 @@ static DEFINE_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", },
+ { .compatible = "imagis,ist3038c", .data = (void *)IST3038C_WHOAMI, },
{ },
};
MODULE_DEVICE_TABLE(of, imagis_of_match);
#endif
+static const struct i2c_device_id imagis_ts_i2c_id[] = {
+ { "ist3038c", IST3038C_WHOAMI, },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, imagis_ts_i2c_id);
+
static struct i2c_driver imagis_ts_driver = {
.driver = {
.name = "imagis-touchscreen", @@ -358,10 +367,11 @@ static struct i2c_driver imagis_ts_driver = {
.of_match_table = of_match_ptr(imagis_of_match), }, .probe =
imagis_probe, + .id_table = imagis_ts_i2c_id, };
module_i2c_driver(imagis_ts_driver); -MODULE_DESCRIPTION("Imagis IST3038C Touchscreen Driver");
+MODULE_DESCRIPTION("Imagis IST30XXC Touchscreen Driver");
MODULE_AUTHOR("Markuss Broks<markuss.broks@xxxxxxxxx>");
MODULE_LICENSE("GPL");
Additionally, there used to be my series [1] that generalized the
driver, but it never got applied. I will re-send it. It introduces
`struct imagis_properties`, which contains register addresses for the
registers that we use to read the touch input. In your specific case, I
believe it should be:
static const struct imagis_properties imagis_3032c_data =
{
.interrupt_msg_cmd = IST3038C_REG_INTR_MESSAGE,
.touch_coord_cmd = IST3038C_REG_TOUCH_COORD,
.whoami_cmd = IST3038C_REG_CHIPID,
.whoami_val = IST3032C_WHOAMI, /* change it to your whoami */
};
As for the voltage set, I believe this does not belong in a kernel
driver. You should set it in device-tree with `regulator-max-microvolt`
and `regulator-min-microvolt`.
Yours,
- Markuss
[1]:
https://lore.kernel.org/lkml/20220504152406.8730-1-markuss.broks@xxxxxxxxx/