On Tue, Aug 1, 2017 at 8:46 AM, Pali Rohár <pali.rohar@xxxxxxxxx> wrote:
> On Tuesday 01 August 2017 08:37:28 Andy Lutomirski wrote:
>> This adds a sysfs binary attribute 'wdg' on the bus device
>> (i.e. /sys/class/wmi_bus/wmi_bus-*/wdg) that contains the raw _WDG
>> data from ACPI. This can be used along with the wmi-bmof driver to
>> decode the raw interface data from ACPI.
>>
>> There is very little new information here, as most of the contents
>> were already exposed in sysfs attributes on the wmi devices.
>>
>> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
>> ---
>> drivers/platform/x86/wmi.c | 63 ++++++++++++++++++++++++++++++++++++++++++++--
>> 1 file changed, 61 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
>> index 1a764e311e11..37ca56aa6025 100644
>> --- a/drivers/platform/x86/wmi.c
>> +++ b/drivers/platform/x86/wmi.c
>> @@ -76,6 +76,11 @@ struct wmi_block {
>> bool read_takes_no_args;
>> };
>>
>> +struct wmi_bus_priv {
>> + union acpi_object *wdg_obj;
>> + struct bin_attribute wdg_bin_attr;
>> + bool wdg_bin_attr_created;
>> +};
>>
>> /*
>> * If the GUID data block is marked as expensive, we must enable and
>> @@ -938,6 +943,7 @@ static bool guid_already_parsed(struct acpi_device *device,
>> */
>> static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
>> {
>> + struct wmi_bus_priv *priv = dev_get_drvdata(wmi_bus_dev);
>> struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
>> const struct guid_block *gblock;
>> struct wmi_block *wblock, *next;
>> @@ -1017,11 +1023,35 @@ static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
>> }
>> }
>>
>> + priv->wdg_obj = obj;
>> + return 0;
>> +
>> out_free_pointer:
>> kfree(out.pointer);
>> return retval;
>> }
>>
>> +static ssize_t
>> +read_wdg(struct file *filp, struct kobject *kobj,
>> + struct bin_attribute *attr,
>> + char *buf, loff_t off, size_t count)
>> +{
>> + struct wmi_bus_priv *priv =
>> + container_of(attr, struct wmi_bus_priv, wdg_bin_attr);
>> +
>> + if (off < 0)
>> + return -EINVAL;
>> +
>> + if (off >= priv->wdg_obj->buffer.length)
>> + return 0;
>> +
>> + if (count > priv->wdg_obj->buffer.length - off)
>> + count = priv->wdg_obj->buffer.length - off;
>> +
>> + memcpy(buf, priv->wdg_obj->buffer.pointer + off, count);
>> + return count;
>> +}
>> +
>> /*
>> * WMI can have EmbeddedControl access regions. In which case, we just want to
>> * hand these off to the EC driver.
>> @@ -1138,6 +1168,8 @@ static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
>>
>> static int acpi_wmi_remove(struct platform_device *device)
>> {
>> + struct device *wmi_bus_dev = dev_get_drvdata(&device->dev);
>> + struct wmi_bus_priv *priv = dev_get_drvdata(wmi_bus_dev);
>> struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
>>
>> acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
>> @@ -1145,7 +1177,13 @@ static int acpi_wmi_remove(struct platform_device *device)
>> acpi_remove_address_space_handler(acpi_device->handle,
>> ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
>> wmi_free_devices(acpi_device);
>> - device_unregister((struct device *)dev_get_drvdata(&device->dev));
>> +
>> + if (priv->wdg_bin_attr_created)
>> + sysfs_remove_bin_file(&wmi_bus_dev->kobj,
>> + &priv->wdg_bin_attr);
>> + kfree(priv->wdg_obj);
>> + kfree(priv);
>> + device_unregister(wmi_bus_dev);
>>
>> return 0;
>> }
>> @@ -1154,6 +1192,7 @@ static int acpi_wmi_probe(struct platform_device *device)
>> {
>> struct acpi_device *acpi_device;
>> struct device *wmi_bus_dev;
>> + struct wmi_bus_priv *priv;
>> acpi_status status;
>> int error;
>>
>> @@ -1190,14 +1229,34 @@ static int acpi_wmi_probe(struct platform_device *device)
>> }
>> dev_set_drvdata(&device->dev, wmi_bus_dev);
>>
>> + priv = kzalloc(sizeof(struct wmi_bus_priv), GFP_KERNEL);
>> + if (!priv) {
>> + error = -ENOMEM;
>> + goto err_remove_busdev;
>> + }
>> + dev_set_drvdata(wmi_bus_dev, priv);
>> +
>> error = parse_wdg(wmi_bus_dev, acpi_device);
>> if (error) {
>> pr_err("Failed to parse WDG method\n");
>> - goto err_remove_busdev;
>> + goto err_free_priv;
>> }
>>
>> + sysfs_bin_attr_init(&priv->wdg_bin_attr);
>> + priv->wdg_bin_attr.attr.name = "wdg";
>> + priv->wdg_bin_attr.attr.mode = 0400;
>> + priv->wdg_bin_attr.read = read_wdg;
>> + priv->wdg_bin_attr.size = priv->wdg_obj->buffer.length;
>> +
>> + /* A failure here isn't fatal. */
>> + if (sysfs_create_bin_file(&wmi_bus_dev->kobj, &priv->wdg_bin_attr) == 0)
>> + priv->wdg_bin_attr_created = true;
>
> There should be at least some warning...
Fixed for v2.
--Andy
