[PATCH v11 37/56] Input: atmel_mxt_ts - implement improved debug message interface

Jiada Wang
2020-05-08T05:59:25Z

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

Implement improved debug message interface

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
(cherry picked from ndyer/linux/for-upstream commit 078569c13c88dcb6f8d882bfe17168587712df7d)
[gdavis: Resolve forward port conflicts due to v4.14.51 commit
960fe000b1d3 ("Input: atmel_mxt_ts - fix the firmware
update").]
Signed-off-by: George G. Davis <george_davis@mentor.com>
[gdavis: Squash fixes from Dirk Behme:
- Input: atmel_mxt_ts - add missing unlock in error path
- Input: atmel_mxt_ts - add missing unlock in error path
- Input: atmel_mxt_ts - call mxt_debug_msg_remove() in error path
- Input: atmel_mxt_ts - protect debug_v2_enabled by mutex
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
[gdavis: Squash fix from Vladimir Zapolskiy:
- Input: atmel_mxt_ts - simplify debug_msg binary attribute
handling]
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
[jiada: Rename mxt_debug_notify_show to debug_notify_show
Rename mxt_debug_v2_enable_store to debug_v2_enable_store
Add debug_v2_enable_show
Replace DEVICE_ATTR with DEVICE_ATTR_[RW|RO] ]
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 201 ++++++++++++++++++++++-
1 file changed, 200 insertions(+), 1 deletion(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 7d48c4d1f57d..92c883087a4f 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -243,6 +243,8 @@ enum t100_type {

#define MXT_PIXELS_PER_MM 20

+#define DEBUG_MSG_MAX 200
+
struct mxt_info {
u8 family_id;
u8 variant_id;
@@ -337,6 +339,11 @@ struct mxt_data {
u8 t100_aux_area;
u8 t100_aux_vect;
bool debug_enabled;
+ bool debug_v2_enabled;
+ u8 *debug_msg_data;
+ u16 debug_msg_count;
+ struct bin_attribute *debug_msg_attr;
+ struct mutex debug_msg_lock;
u8 max_reportid;
u32 config_crc;
u32 info_crc;
@@ -469,6 +476,144 @@ static void mxt_dump_message(struct mxt_data *data, u8 *message)
data->T5_msg_size, message);
}

+static void mxt_debug_msg_enable(struct mxt_data *data)
+{
+ struct device *dev = &data->client->dev;
+
+ if (data->debug_v2_enabled)
+ return;
+
+ mutex_lock(&data->debug_msg_lock);
+
+ data->debug_msg_data = kcalloc(DEBUG_MSG_MAX,
+ data->T5_msg_size, GFP_KERNEL);
+ if (!data->debug_msg_data) {
+ mutex_unlock(&data->debug_msg_lock);
+ return;
+ }
+
+ data->debug_v2_enabled = true;
+ mutex_unlock(&data->debug_msg_lock);
+
+ dev_dbg(dev, "Enabled message output\n");
+}
+
+static void mxt_debug_msg_disable(struct mxt_data *data)
+{
+ struct device *dev = &data->client->dev;
+
+ if (!data->debug_v2_enabled)
+ return;
+
+ mutex_lock(&data->debug_msg_lock);
+
+ data->debug_v2_enabled = false;
+
+ kfree(data->debug_msg_data);
+ data->debug_msg_data = NULL;
+ data->debug_msg_count = 0;
+ mutex_unlock(&data->debug_msg_lock);
+ dev_dbg(dev, "Disabled message output\n");
+}
+
+static void mxt_debug_msg_add(struct mxt_data *data, u8 *msg)
+{
+ struct device *dev = &data->client->dev;
+
+ mutex_lock(&data->debug_msg_lock);
+
+ if (!data->debug_msg_data) {
+ mutex_unlock(&data->debug_msg_lock);
+ dev_err(dev, "No buffer!\n");
+ return;
+ }
+
+ if (data->debug_msg_count < DEBUG_MSG_MAX) {
+ memcpy(data->debug_msg_data +
+ data->debug_msg_count * data->T5_msg_size,
+ msg,
+ data->T5_msg_size);
+ data->debug_msg_count++;
+ } else {
+ dev_dbg(dev, "Discarding %u messages\n", data->debug_msg_count);
+ data->debug_msg_count = 0;
+ }
+
+ mutex_unlock(&data->debug_msg_lock);
+
+ sysfs_notify(&data->client->dev.kobj, NULL, "debug_notify");
+}
+
+static ssize_t mxt_debug_msg_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf, loff_t off, size_t bytes)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct mxt_data *data = dev_get_drvdata(dev);
+ int count;
+ size_t bytes_read;
+
+ if (!data->debug_msg_data) {
+ dev_err(dev, "No buffer!\n");
+ return 0;
+ }
+
+ count = bytes / data->T5_msg_size;
+
+ if (count > DEBUG_MSG_MAX)
+ count = DEBUG_MSG_MAX;
+
+ mutex_lock(&data->debug_msg_lock);
+
+ if (count > data->debug_msg_count)
+ count = data->debug_msg_count;
+
+ bytes_read = count * data->T5_msg_size;
+
+ memcpy(buf, data->debug_msg_data, bytes_read);
+ data->debug_msg_count = 0;
+
+ mutex_unlock(&data->debug_msg_lock);
+
+ return bytes_read;
+}
+
+static struct bin_attribute debug_msg_attr = {
+ .attr = {
+ .name = "debug_msg",
+ .mode = 0444,
+ },
+ .read = mxt_debug_msg_read,
+};
+
+static int mxt_debug_msg_init(struct mxt_data *data)
+{
+ /*
+ * Binary attribute is not used in callback, removal is done by name,
+ * so it is safe to update a single struct bin_attribute entity
+ */
+ debug_msg_attr.size = data->T5_msg_size * DEBUG_MSG_MAX;
+
+ if (sysfs_create_bin_file(&data->client->dev.kobj,
+ &debug_msg_attr) < 0) {
+ dev_err(&data->client->dev, "Failed to create %s\n",
+ debug_msg_attr.attr.name);
+ return -EINVAL;
+ }
+
+ data->debug_msg_attr = &debug_msg_attr;
+
+ return 0;
+}
+
+static void mxt_debug_msg_remove(struct mxt_data *data)
+{
+ if (data->debug_msg_attr) {
+ sysfs_remove_bin_file(&data->client->dev.kobj,
+ data->debug_msg_attr);
+ data->debug_msg_attr = NULL;
+ }
+}
+
static int mxt_wait_for_completion(struct mxt_data *data,
struct completion *comp,
unsigned int timeout_ms)
@@ -1257,6 +1402,9 @@ static int mxt_proc_message(struct mxt_data *data, u8 *message)
if (dump)
mxt_dump_message(data, message);

+ if (data->debug_v2_enabled)
+ mxt_debug_msg_add(data, message);
+
return 1;
}

@@ -2660,6 +2808,10 @@ static int mxt_initialize(struct mxt_data *data)
if (error)
return error;

+ error = mxt_debug_msg_init(data);
+ if (error)
+ goto err_free_sysfs;
+
error = request_firmware_nowait(THIS_MODULE, true,
data->cfg_name ?
data->cfg_name : MXT_CFG_NAME,
@@ -2669,11 +2821,13 @@ static int mxt_initialize(struct mxt_data *data)
if (error) {
dev_err(&client->dev, "Failed to invoke firmware loader: %d\n",
error);
- goto err_free_sysfs;
+ goto err_free_dbg_msg;
}

return 0;

+err_free_dbg_msg:
+ mxt_debug_msg_remove(data);
err_free_sysfs:
mxt_sysfs_remove(data);
return error;
@@ -3335,6 +3489,7 @@ static int mxt_enter_bootloader(struct mxt_data *data)
return ret;

data->in_bootloader = true;
+ mxt_debug_msg_remove(data);
mxt_sysfs_remove(data);
mxt_free_input_device(data);
mxt_free_object_table(data);
@@ -3506,6 +3661,44 @@ static ssize_t update_cfg_store(struct device *dev,
return ret;
}

+static ssize_t debug_notify_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0\n");
+}
+
+static ssize_t debug_v2_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) {
+ if (i == 1)
+ mxt_debug_msg_enable(data);
+ else
+ mxt_debug_msg_disable(data);
+
+ ret = count;
+ } else {
+ dev_dbg(dev, "debug_enabled write error\n");
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static ssize_t debug_v2_enable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mxt_data *data = dev_get_drvdata(dev);
+ char c;
+
+ c = data->debug_v2_enabled ? '1' : '0';
+ return scnprintf(buf, PAGE_SIZE, "%c\n", c);
+}
+
static ssize_t debug_enable_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -3553,6 +3746,8 @@ static DEVICE_ATTR_RO(object);
static DEVICE_ATTR_WO(update_cfg);
static DEVICE_ATTR_RO(config_crc);
static DEVICE_ATTR_RW(debug_enable);
+static DEVICE_ATTR_RW(debug_v2_enable);
+static DEVICE_ATTR_RO(debug_notify);

static struct attribute *mxt_attrs[] = {
&dev_attr_fw_version.attr,
@@ -3561,6 +3756,8 @@ static struct attribute *mxt_attrs[] = {
&dev_attr_update_cfg.attr,
&dev_attr_config_crc.attr,
&dev_attr_debug_enable.attr,
+ &dev_attr_debug_v2_enable.attr,
+ &dev_attr_debug_notify.attr,
NULL
};

@@ -3851,6 +4048,7 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
init_completion(&data->chg_completion);
init_completion(&data->reset_completion);
init_completion(&data->crc_completion);
+ mutex_init(&data->debug_msg_lock);

data->suspend_mode = dmi_check_system(chromebook_T9_suspend_dmi) ?
MXT_SUSPEND_T9_CTRL : MXT_SUSPEND_DEEP_SLEEP;
@@ -3916,6 +4114,7 @@ static int mxt_remove(struct i2c_client *client)

disable_irq(data->irq);
sysfs_remove_group(&client->dev.kobj, &mxt_fw_attr_group);
+ mxt_debug_msg_remove(data);
mxt_sysfs_remove(data);
mxt_free_input_device(data);
mxt_free_object_table(data);
--
2.17.1