Add support for the msg2638 touchscreen IC from MStar.
This driver reuses zinitix.c structure, while the checksum and irq handler
functions are based on out-of-tree driver for Alcatel Idol 3 (4.7").
Signed-off-by: Vincent Knecht
---
Changed in v4:
- rename from msg26xx to msg2638, following compatible string change
- rename mstar_* functions to msg2638_* for consistency
- add RESET_DELAY define and use it in msg2638_power_on()
- change a few dev_err() calls to be on one line only
- add missing \n in a few dev_err() strings
Changed in v3:
- no change
Changed in v2:
- don't use bitfields in packet struct, to prevent endian-ness related problems
(Dmitry)
- fix reset gpiod calls order in mstar_power_on() (Dmitry)
---
drivers/input/touchscreen/Kconfig | 12 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/msg2638.c | 362
3 files changed, 375 insertions(+)
create mode 100644 drivers/input/touchscreen/msg2638.c
diff --git a/drivers/input/touchscreen/Kconfig
b/drivers/input/touchscreen/Kconfig
index f012fe746df0..fefbe1c1bb10 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -1334,4 +1334,16 @@ config TOUCHSCREEN_ZINITIX
To compile this driver as a module, choose M here: the
module will be called zinitix.
+config TOUCHSCREEN_MSG2638
+ tristate "MStar msg2638 touchscreen support"
+ depends on I2C
+ depends on GPIOLIB || COMPILE_TEST
+ help
+ Say Y here if you have an I2C touchscreen using MStar msg2638.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called msg2638.
+
endif
diff --git a/drivers/input/touchscreen/Makefile
b/drivers/input/touchscreen/Makefile
index 6233541e9173..83e516cb3d33 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -112,3 +112,4 @@ obj-$(CONFIG_TOUCHSCREEN_ROHM_BU21023) +=
rohm_bu21023.o
obj-$(CONFIG_TOUCHSCREEN_RASPBERRYPI_FW) += raspberrypi-ts.o
obj-$(CONFIG_TOUCHSCREEN_IQS5XX) += iqs5xx.o
obj-$(CONFIG_TOUCHSCREEN_ZINITIX) += zinitix.o
+obj-$(CONFIG_TOUCHSCREEN_MSG2638) += msg2638.o
diff --git a/drivers/input/touchscreen/msg2638.c
b/drivers/input/touchscreen/msg2638.c
new file mode 100644
index ..e00cff923fe2
--- /dev/null
+++ b/drivers/input/touchscreen/msg2638.c
@@ -0,0 +1,362 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for MStar msg2638 touchscreens
+ *
+ * Copyright (c) 2021 Vincent Knecht
+ *
+ * Checksum and IRQ handler based on mstar_drv_common.c and
mstar_drv_mutual_fw_control.c
+ * Copyright (c) 2006-2012 MStar Semiconductor, Inc.
+ *
+ * Driver structure based on zinitix.c by Michael Srba
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#define MODE_DATA_RAW 0x5A
+
+#define TPD_WIDTH 2048
+#define TPD_HEIGHT 2048
+
+#define MAX_SUPPORTED_FINGER_NUM 5
+
+#define CHIP_ON_DELAY 15 // ms
+#define FIRMWARE_ON_DELAY 50 // ms
+#define RESET_DELAY10 // ms
+
+struct point_coord {
+ u16 x;
+ u16 y;
+};
+
+struct packet {
+ u8 xy_hi; /* higher bits of x and y coordinates */
+ u8 x_low;
+ u8 y_low;
+ u8 pressure;
+};
+
+struct touch_event {
+ u8 mode;
+ struct packet pkt[MAX_SUPPORTED_FINGER_NUM];
+ u8 proximity;
+ u8 checksum;
+};
+
+struct msg2638_ts_data {
+ struct i2c_client *client;
+ struct input_dev *input_dev;
+ struct touchscreen_properties prop;
+ struct regulator_bulk_data supplies[2];
+ struct gpio_desc *reset_gpiod;
+};
+
+static int msg2638_init_regulators(struct msg2638_ts_data *msg2638)
+{
+ struct i2c_client *client = msg2638->client;
+ int error;
+
+ msg2638->supplies[0].supply = "vdd";
+ msg2638->supplies[1].supply = "vddio";
+ error = devm_regulator_bulk_get(>dev,
+ ARRAY_SIZE(msg2638->supplies),
+ msg2638->supplies);
+ if (error < 0) {
+ dev_err(>dev, "Failed to get regulators: %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static void msg2638_power_on(struct msg2638_ts_data *msg2638)
+{
+ gpiod_set_value(msg2638->reset_gpiod, 1);
+ mdelay(RESET_DELAY);
+ gpiod_set_value(msg2638->reset_gpiod, 0);
+ mdelay(FIRMWARE_ON_DELAY);
+
+ enable_irq(msg2638->client->irq);
+}
+
+static void msg2638_report_finger(struct msg2638_ts_data *msg2638, int slot,
+ const struct point_coord *pc)
+{
+ input_mt_slot(msg2638->input_dev, slot);
+
