Hi Manish,
On Thu, Jul 7, 2022 at 3:15 PM Manish Mandlik <mmandlik@xxxxxxxxxx> wrote:
>
> Since device/firmware dump is a debugging feature, we may not need it
> all the time. Add a sysfs attribute to enable/disable bluetooth
> devcoredump capturing. The default state of this feature would be
> disabled and it can be enabled by echoing 1 to enable_coredump sysfs
> entry as follow:
>
> $ echo 1 > /sys/class/bluetooth/<device>/enable_coredump
>
> Signed-off-by: Manish Mandlik <mmandlik@xxxxxxxxxx>
> ---
>
> Changes in v3:
> - New patch in the series to enable/disable feature via sysfs entry
>
> net/bluetooth/hci_sysfs.c | 36 ++++++++++++++++++++++++++++++++++++
> 1 file changed, 36 insertions(+)
>
> diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
> index 4e3e0451b08c..df0d54a5ae3f 100644
> --- a/net/bluetooth/hci_sysfs.c
> +++ b/net/bluetooth/hci_sysfs.c
> @@ -91,9 +91,45 @@ static void bt_host_release(struct device *dev)
> module_put(THIS_MODULE);
> }
>
> +#ifdef CONFIG_DEV_COREDUMP
> +static ssize_t enable_coredump_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hci_dev *hdev = to_hci_dev(dev);
> +
> + return scnprintf(buf, 3, "%d\n", hdev->dump.enabled);
> +}
> +
> +static ssize_t enable_coredump_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct hci_dev *hdev = to_hci_dev(dev);
> +
> + /* Consider any non-zero value as true */
> + if (simple_strtol(buf, NULL, 10))
> + hdev->dump.enabled = true;
> + else
> + hdev->dump.enabled = false;
> +
> + return count;
> +}
> +DEVICE_ATTR_RW(enable_coredump);
> +#endif
> +
> +static struct attribute *bt_host_attrs[] = {
> +#ifdef CONFIG_DEV_COREDUMP
> + &dev_attr_enable_coredump.attr,
> +#endif
> + NULL,
> +};
> +ATTRIBUTE_GROUPS(bt_host);
> +
> static const struct device_type bt_host = {
> .name = "host",
> .release = bt_host_release,
> + .groups = bt_host_groups,
> };
>
> void hci_init_sysfs(struct hci_dev *hdev)
> --
> 2.37.0.rc0.161.g10f37bed90-goog
It seems devcoredump.c creates its own sysfs entries so perhaps this
should be included there and documented in sysfs-devices-coredump.
--
Luiz Augusto von Dentz
