[PATCH v11 36/56] Input: atmel_mxt_ts - implement debug output for messages

Jiada Wang
2020-05-08T06:00:14Z

From: Nick Dyer <nick.dyer@itdev.co.uk>

Add a debug switch which causes all messages from the touch controller to
be dumped to the dmesg log with a set prefix "MXT MSG:". This is used by
Atmel user-space utilities to debug touch operation. Enabling this output
does impact touch performance.

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
(cherry picked from ndyer/linux/for-upstream commit 3c3fcfdd4889dfeb1c80ae8cd94a622c6342b06a)
[gdavis: Forward port and fix conflicts.]
Signed-off-by: George G. Davis <george_davis@mentor.com>
[jiada: Rename mxt_debug_enable_store to debug_enable_store
Rename mxt_debug_enable_show to debug_enable_show
Replace DEVICE_ATTR with DEVICE_ATTR_RW]
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 46 ++++++++++++++++++++++--
1 file changed, 43 insertions(+), 3 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 1027ebbc3978..7d48c4d1f57d 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -336,6 +336,7 @@ struct mxt_data {
u8 t100_aux_ampl;
u8 t100_aux_area;
u8 t100_aux_vect;
+ bool debug_enabled;
u8 max_reportid;
u32 config_crc;
u32 info_crc;
@@ -461,8 +462,11 @@ static bool mxt_object_readable(unsigned int type)

static void mxt_dump_message(struct mxt_data *data, u8 *message)
{
- dev_dbg(&data->client->dev, "message: %*ph\n",
- data->T5_msg_size, message);
+ /* debug message with prefix 'MXT MSG:' used by
+ * Atmel user-space utilities to debug touch operation
+ */
+ dev_dbg(&data->client->dev, "MXT MSG: %*ph\n",
+ data->T5_msg_size, message);
}

static int mxt_wait_for_completion(struct mxt_data *data,
@@ -1212,6 +1216,7 @@ static void mxt_proc_t93_messages(struct mxt_data *data, u8 *msg)
static int mxt_proc_message(struct mxt_data *data, u8 *message)
{
u8 report_id = message[0];
+ bool dump = data->debug_enabled;

if (report_id == MXT_RPTID_NOMSG)
return 0;
@@ -1246,9 +1251,12 @@ static int mxt_proc_message(struct mxt_data *data, u8 *message)
} else if (report_id == data->T93_reportid) {
mxt_proc_t93_messages(data, message);
} else {
- mxt_dump_message(data, message);
+ dump = true;
}

+ if (dump)
+ mxt_dump_message(data, message);
+
return 1;
}

@@ -3498,6 +3506,36 @@ static ssize_t update_cfg_store(struct device *dev,
return ret;
}

+static ssize_t debug_enable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mxt_data *data = dev_get_drvdata(dev);
+ char c;
+
+ c = data->debug_enabled ? '1' : '0';
+ return scnprintf(buf, PAGE_SIZE, "%c\n", c);
+}
+
+static ssize_t debug_enable_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct mxt_data *data = dev_get_drvdata(dev);
+ u8 i;
+ ssize_t ret;
+
+ if (kstrtou8(buf, 0, &i) == 0 && i < 2) {
+ data->debug_enabled = (i == 1);
+
+ dev_dbg(dev, "%s\n", i ? "debug enabled" : "debug disabled");
+ ret = count;
+ } else {
+ dev_dbg(dev, "debug_enabled write error\n");
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
static DEVICE_ATTR_WO(update_fw);

static struct attribute *mxt_fw_attrs[] = {
@@ -3514,6 +3552,7 @@ static DEVICE_ATTR_RO(hw_version);
static DEVICE_ATTR_RO(object);
static DEVICE_ATTR_WO(update_cfg);
static DEVICE_ATTR_RO(config_crc);
+static DEVICE_ATTR_RW(debug_enable);

static struct attribute *mxt_attrs[] = {
&dev_attr_fw_version.attr,
@@ -3521,6 +3560,7 @@ static struct attribute *mxt_attrs[] = {
&dev_attr_object.attr,
&dev_attr_update_cfg.attr,
&dev_attr_config_crc.attr,
+ &dev_attr_debug_enable.attr,
NULL
};

--
2.17.1