[PATCH v3 5/14] input: cyapa: add read firmware image and raw data interfaces in debugfs system

From: Dudley Du
Date: Fri Jul 04 2014 - 06:48:54 EST


Add read_fw and raw_data debugfs interfaces for easier issues location
and collection when report by user.
TEST=test on Chromebooks.

Signed-off-by: Dudley Du <dudl@xxxxxxxxxxx>
---
drivers/input/mouse/cyapa.c | 220 +++++++++++++++++++++++++++++++++++++++++++
drivers/input/mouse/cyapa.h | 11 +++
2 files changed, 231 insertions(+)

diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
index fb62de9..8c441cc 100644
--- a/drivers/input/mouse/cyapa.c
+++ b/drivers/input/mouse/cyapa.c
@@ -39,6 +39,9 @@

const char unique_str[] = "CYTRA";

+/* global root node of the cyapa debugfs directory. */
+static struct dentry *cyapa_debugfs_root;
+

void cyapa_enable_irq(struct cyapa *cyapa)
{
@@ -545,6 +548,205 @@ done:
}

/*
+ **************************************************************
+ * debugfs interface
+ **************************************************************
+*/
+static int cyapa_debugfs_open(struct inode *inode, struct file *file)
+{
+ struct cyapa *cyapa = inode->i_private;
+ int ret;
+
+ if (!cyapa)
+ return -ENODEV;
+
+ ret = mutex_lock_interruptible(&cyapa->debugfs_mutex);
+ if (ret)
+ return ret;
+
+ if (!kobject_get(&cyapa->client->dev.kobj)) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ file->private_data = cyapa;
+
+ if (cyapa->fw_image) {
+ ret = 0;
+ goto out;
+ }
+
+ if (!cyapa_state_sync_enter(cyapa))
+ return -EBUSY;
+ /*
+ * If firmware hasn't been read yet, read it all in one pass.
+ * Subsequent opens will reuse the data in this same buffer.
+ */
+ if (cyapa->ops->read_fw)
+ ret = cyapa->ops->read_fw(cyapa);
+ else
+ ret = -EPERM;
+ cyapa_state_sync_exit(cyapa);
+
+ /* redetect trackpad device states. */
+ cyapa_detect_async(cyapa, 0);
+
+out:
+ mutex_unlock(&cyapa->debugfs_mutex);
+ return ret;
+}
+
+static int cyapa_debugfs_release(struct inode *inode, struct file *file)
+{
+ struct cyapa *cyapa = file->private_data;
+ int ret;
+
+ if (!cyapa)
+ return 0;
+
+ ret = mutex_lock_interruptible(&cyapa->debugfs_mutex);
+ if (ret)
+ return ret;
+ file->private_data = NULL;
+ kobject_put(&cyapa->client->dev.kobj);
+ mutex_unlock(&cyapa->debugfs_mutex);
+
+ return 0;
+}
+
+/* Return some bytes from the buffered firmware image, starting from *ppos */
+static ssize_t cyapa_debugfs_read_fw(struct file *file, char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct cyapa *cyapa = file->private_data;
+
+ if (!cyapa->fw_image)
+ return -EINVAL;
+
+ if (*ppos >= cyapa->fw_image_size)
+ return 0;
+
+ if (count + *ppos > cyapa->fw_image_size)
+ count = cyapa->fw_image_size - *ppos;
+
+ if (copy_to_user(buffer, &cyapa->fw_image[*ppos], count))
+ return -EFAULT;
+
+ *ppos += count;
+ return count;
+}
+
+static const struct file_operations cyapa_read_fw_fops = {
+ .open = cyapa_debugfs_open,
+ .release = cyapa_debugfs_release,
+ .read = cyapa_debugfs_read_fw
+};
+
+static int cyapa_debugfs_raw_data_open(struct inode *inode, struct file *file)
+{
+ struct cyapa *cyapa = inode->i_private;
+ int ret;
+
+ if (!cyapa)
+ return -ENODEV;
+
+ ret = mutex_lock_interruptible(&cyapa->debugfs_mutex);
+ if (ret)
+ return ret;
+
+ if (!kobject_get(&cyapa->client->dev.kobj)) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ file->private_data = cyapa;
+
+ if (!cyapa_state_sync_enter(cyapa)) {
+ ret = -EBUSY;
+ goto out;
+ }
+ if (cyapa->ops->read_raw_data)
+ ret = cyapa->ops->read_raw_data(cyapa);
+ else
+ ret = -EPERM;
+ cyapa_state_sync_exit(cyapa);
+out:
+ mutex_unlock(&cyapa->debugfs_mutex);
+ return ret;
+}
+
+static int cyapa_debugfs_raw_data_release(struct inode *inode,
+ struct file *file)
+{
+ struct cyapa *cyapa = file->private_data;
+ int ret;
+
+ if (!cyapa)
+ return 0;
+
+ ret = mutex_lock_interruptible(&cyapa->debugfs_mutex);
+ if (ret)
+ return ret;
+ file->private_data = NULL;
+ kobject_put(&cyapa->client->dev.kobj);
+ mutex_unlock(&cyapa->debugfs_mutex);
+
+ return 0;
+}
+
+/* Always return the sensors' latest raw data from trackpad device. */
+static ssize_t cyapa_debugfs_read_raw_data(struct file *file,
+ char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct cyapa *cyapa = file->private_data;
+
+ if (!cyapa->tp_raw_data)
+ return -EINVAL;
+
+ if (*ppos >= cyapa->tp_raw_data_size)
+ return 0;
+
+ if (count + *ppos > cyapa->tp_raw_data_size)
+ count = cyapa->tp_raw_data_size - *ppos;
+
+ if (copy_to_user(buffer, &cyapa->tp_raw_data[*ppos], count))
+ return -EFAULT;
+
+ *ppos += count;
+ return count;
+}
+
+static const struct file_operations cyapa_read_raw_data_fops = {
+ .open = cyapa_debugfs_raw_data_open,
+ .release = cyapa_debugfs_raw_data_release,
+ .read = cyapa_debugfs_read_raw_data
+};
+
+static int cyapa_debugfs_init(struct cyapa *cyapa)
+{
+ struct device *dev = &cyapa->client->dev;
+
+ if (!cyapa_debugfs_root)
+ return -ENODEV;
+
+ cyapa->dentry_dev = debugfs_create_dir(kobject_name(&dev->kobj),
+ cyapa_debugfs_root);
+
+ if (!cyapa->dentry_dev)
+ return -ENODEV;
+
+ mutex_init(&cyapa->debugfs_mutex);
+
+ debugfs_create_file(CYAPA_DEBUGFS_READ_FW, S_IRUSR, cyapa->dentry_dev,
+ cyapa, &cyapa_read_fw_fops);
+
+ debugfs_create_file(CYAPA_DEBUGFS_RAW_DATA, S_IRUSR, cyapa->dentry_dev,
+ cyapa, &cyapa_read_raw_data_fops);
+ return 0;
+}
+
+/*
* Sysfs Interface.
*/

@@ -978,6 +1180,13 @@ static int cyapa_probe(struct i2c_client *client,
if (sysfs_create_group(&client->dev.kobj, &cyapa_sysfs_group))
dev_warn(dev, "error creating sysfs entries.\n");

+ /* Create a global debugfs root for all cyapa devices */
+ cyapa_debugfs_root = debugfs_create_dir("cyapa", NULL);
+ if (cyapa_debugfs_root == ERR_PTR(-ENODEV))
+ cyapa_debugfs_root = NULL;
+ if (cyapa_debugfs_init(cyapa))
+ dev_warn(dev, "error creating debugfs entries.\n");
+
#ifdef CONFIG_PM_SLEEP
if (device_can_wakeup(dev) &&
sysfs_merge_group(&client->dev.kobj, &cyapa_power_wakeup_group))
@@ -1009,8 +1218,19 @@ static int cyapa_remove(struct i2c_client *client)
#ifdef CONFIG_PM_RUNTIME
sysfs_unmerge_group(&client->dev.kobj, &cyapa_power_runtime_group);
#endif
+
+ kfree(cyapa->fw_image);
+ cyapa->fw_image = NULL;
+ cyapa->fw_image_size = 0;
+ kfree(cyapa->tp_raw_data);
+ cyapa->tp_raw_data = NULL;
+ cyapa->tp_raw_data_size = 0;
free_irq(cyapa->irq, cyapa);

+ debugfs_remove_recursive(cyapa->dentry_dev);
+ debugfs_remove_recursive(cyapa_debugfs_root);
+ mutex_destroy(&cyapa->debugfs_mutex);
+
input_unregister_device(cyapa->input);
if (cyapa->ops->set_power_mode)
cyapa->ops->set_power_mode(cyapa, PWR_MODE_OFF, 0);
diff --git a/drivers/input/mouse/cyapa.h b/drivers/input/mouse/cyapa.h
index 5931a83..0ec76d9 100644
--- a/drivers/input/mouse/cyapa.h
+++ b/drivers/input/mouse/cyapa.h
@@ -258,6 +258,17 @@ struct cyapa {
bool irq_enabled;
bool prev_irq_enabled;

+ /* per-instance debugfs root */
+ struct dentry *dentry_dev;
+
+ /* Buffer to store firmware read using debugfs */
+ struct mutex debugfs_mutex;
+ u8 *fw_image;
+ size_t fw_image_size;
+ /* Buffer to store sensors' raw data */
+ u8 *tp_raw_data;
+ size_t tp_raw_data_size;
+
const struct cyapa_dev_ops *ops;
};

--
1.7.9.5


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