[PATCHv4 2/4] Input: EXC3000: add EXC80H60 and EXC80H84 support

From: Sebastian Reichel
Date: Wed Aug 05 2020 - 16:11:44 EST


This adds support for EXC80H60 and EXCH84 controllers, which
use a different event type id and have two extra bits for the
resolution (so the maximum is 16K instead of 4K).

Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
---
.../input/touchscreen/eeti,exc3000.yaml | 5 +-
drivers/input/touchscreen/exc3000.c | 80 +++++++++++++++----
2 files changed, 70 insertions(+), 15 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/touchscreen/eeti,exc3000.yaml b/Documentation/devicetree/bindings/input/touchscreen/eeti,exc3000.yaml
index 022aa69a5dfe..7e6e23f8fa00 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/eeti,exc3000.yaml
+++ b/Documentation/devicetree/bindings/input/touchscreen/eeti,exc3000.yaml
@@ -14,7 +14,10 @@ allOf:

properties:
compatible:
- const: eeti,exc3000
+ enum:
+ - eeti,exc3000
+ - eeti,exc80h60
+ - eeti,exc80h84
reg:
const: 0x2a
interrupts:
diff --git a/drivers/input/touchscreen/exc3000.c b/drivers/input/touchscreen/exc3000.c
index 555a14305cd4..b497bd2ae41d 100644
--- a/drivers/input/touchscreen/exc3000.c
+++ b/drivers/input/touchscreen/exc3000.c
@@ -16,6 +16,7 @@
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/sizes.h>
#include <linux/timer.h>
#include <asm/unaligned.h>

@@ -23,11 +24,43 @@
#define EXC3000_SLOTS_PER_FRAME 5
#define EXC3000_LEN_FRAME 66
#define EXC3000_LEN_POINT 10
-#define EXC3000_MT_EVENT 6
+
+#define EXC3000_MT1_EVENT 0x06
+#define EXC3000_MT2_EVENT 0x18
+
#define EXC3000_TIMEOUT_MS 100

+static const struct i2c_device_id exc3000_id[];
+
+struct eeti_dev_info {
+ const char *name;
+ int max_xy;
+};
+
+enum eeti_dev_id {
+ EETI_EXC3000,
+ EETI_EXC80H60,
+ EETI_EXC80H84,
+};
+
+static struct eeti_dev_info exc3000_info[] = {
+ [EETI_EXC3000] = {
+ .name = "EETI EXC3000 Touch Screen",
+ .max_xy = SZ_4K - 1,
+ },
+ [EETI_EXC80H60] = {
+ .name = "EETI EXC80H60 Touch Screen",
+ .max_xy = SZ_16K - 1,
+ },
+ [EETI_EXC80H84] = {
+ .name = "EETI EXC80H84 Touch Screen",
+ .max_xy = SZ_16K - 1,
+ },
+};
+
struct exc3000_data {
struct i2c_client *client;
+ const struct eeti_dev_info *info;
struct input_dev *input;
struct touchscreen_properties prop;
struct timer_list timer;
@@ -58,10 +91,15 @@ static void exc3000_timer(struct timer_list *t)
input_sync(data->input);
}

-static int exc3000_read_frame(struct i2c_client *client, u8 *buf)
+static int exc3000_read_frame(struct exc3000_data *data, u8 *buf)
{
+ struct i2c_client *client = data->client;
+ u8 expected_event = EXC3000_MT1_EVENT;
int ret;

+ if (data->info->max_xy == SZ_16K - 1)
+ expected_event = EXC3000_MT2_EVENT;
+
ret = i2c_master_send(client, "'", 2);
if (ret < 0)
return ret;
@@ -76,19 +114,21 @@ static int exc3000_read_frame(struct i2c_client *client, u8 *buf)
if (ret != EXC3000_LEN_FRAME)
return -EIO;

- if (get_unaligned_le16(buf) != EXC3000_LEN_FRAME ||
- buf[2] != EXC3000_MT_EVENT)
+ if (get_unaligned_le16(buf) != EXC3000_LEN_FRAME)
+ return -EINVAL;
+
+ if (buf[2] != expected_event)
return -EINVAL;

return 0;
}

-static int exc3000_read_data(struct i2c_client *client,
+static int exc3000_read_data(struct exc3000_data *data,
u8 *buf, int *n_slots)
{
int error;

- error = exc3000_read_frame(client, buf);
+ error = exc3000_read_frame(data, buf);
if (error)
return error;

@@ -98,7 +138,7 @@ static int exc3000_read_data(struct i2c_client *client,

if (*n_slots > EXC3000_SLOTS_PER_FRAME) {
/* Read 2nd frame to get the rest of the contacts. */
- error = exc3000_read_frame(client, buf + EXC3000_LEN_FRAME);
+ error = exc3000_read_frame(data, buf + EXC3000_LEN_FRAME);
if (error)
return error;

@@ -118,7 +158,7 @@ static irqreturn_t exc3000_interrupt(int irq, void *dev_id)
int slots, total_slots;
int error;

- error = exc3000_read_data(data->client, buf, &total_slots);
+ error = exc3000_read_data(data, buf, &total_slots);
if (error) {
/* Schedule a timer to release "stuck" contacts */
mod_timer(&data->timer,
@@ -149,13 +189,19 @@ static int exc3000_probe(struct i2c_client *client)
{
struct exc3000_data *data;
struct input_dev *input;
- int error;
+ int error, max_xy;

data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;

data->client = client;
+ data->info = device_get_match_data(&client->dev);
+ if (!data->info) {
+ enum eeti_dev_id eeti_dev_id =
+ i2c_match_id(exc3000_id, client)->driver_data;
+ data->info = &exc3000_info[eeti_dev_id];
+ }
timer_setup(&data->timer, exc3000_timer, 0);

input = devm_input_allocate_device(&client->dev);
@@ -164,11 +210,13 @@ static int exc3000_probe(struct i2c_client *client)

data->input = input;

- input->name = "EETI EXC3000 Touch Screen";
+ input->name = data->info->name;
input->id.bustype = BUS_I2C;

- input_set_abs_params(input, ABS_MT_POSITION_X, 0, 4095, 0, 0);
- input_set_abs_params(input, ABS_MT_POSITION_Y, 0, 4095, 0, 0);
+ max_xy = data->info->max_xy;
+ input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_xy, 0, 0);
+ input_set_abs_params(input, ABS_MT_POSITION_Y, 0, max_xy, 0, 0);
+
touchscreen_parse_properties(input, true, &data->prop);

error = input_mt_init_slots(input, EXC3000_NUM_SLOTS,
@@ -190,14 +238,18 @@ static int exc3000_probe(struct i2c_client *client)
}

static const struct i2c_device_id exc3000_id[] = {
- { "exc3000", 0 },
+ { "exc3000", EETI_EXC3000 },
+ { "exc80h60", EETI_EXC80H60 },
+ { "exc80h84", EETI_EXC80H84 },
{ }
};
MODULE_DEVICE_TABLE(i2c, exc3000_id);

#ifdef CONFIG_OF
static const struct of_device_id exc3000_of_match[] = {
- { .compatible = "eeti,exc3000" },
+ { .compatible = "eeti,exc3000", .data = &exc3000_info[EETI_EXC3000] },
+ { .compatible = "eeti,exc80h60", .data = &exc3000_info[EETI_EXC80H60] },
+ { .compatible = "eeti,exc80h84", .data = &exc3000_info[EETI_EXC80H84] },
{ }
};
MODULE_DEVICE_TABLE(of, exc3000_of_match);
--
2.27.0