Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4255c30f authored by Mario Limonciello's avatar Mario Limonciello Committed by Darren Hart (VMware)
Browse files

platform/x86: dell-smbios-wmi: Disable userspace interface if missing hotfix 



The Dell SMBIOS WMI interface will fail for some more complex calls unless
a WMI hotfix has been included.  Most platforms have this fix available in
a maintenance BIOS release.  In the case the driver is loaded on a
platform without this fix, disable the userspace interface.

A hotfix indicator is present in the dell-wmi-descriptor that represents
whether or not more complex calls will work properly.

"Simple" calls such as those used by dell-laptop and dell-wmi will continue
to work properly so dell-smbios-wmi should not be blocked from binding and
being used as the dell-smbios dispatcher.

Suggested-by: default avatarGirish Prakash <girish.prakash@dell.com>
Signed-off-by: default avatarMario Limonciello <mario.limonciello@dell.com>
Signed-off-by: default avatarDarren Hart (VMware) <dvhart@infradead.org>
parent aaa40965

drivers/platform/x86/dell-smbios-wmi.c

+13 −0
Original line number Diff line number Diff line
@@ -147,7 +147,10 @@ static long dell_smbios_wmi_filter(struct wmi_device *wdev, unsigned int cmd, 


static int dell_smbios_wmi_probe(struct wmi_device *wdev)

{

	struct wmi_driver *wdriver =

		container_of(wdev->dev.driver, struct wmi_driver, driver);

	struct wmi_smbios_priv *priv;

	u32 hotfix;

	int count;

	int ret;
@@ -164,6 +167,16 @@ static int dell_smbios_wmi_probe(struct wmi_device *wdev) 
	if (!dell_wmi_get_size(&priv->req_buf_size))

		return -EPROBE_DEFER;



	/* some SMBIOS calls fail unless BIOS contains hotfix */

	if (!dell_wmi_get_hotfix(&hotfix))

		return -EPROBE_DEFER;

	if (!hotfix) {

		dev_warn(&wdev->dev,

			"WMI SMBIOS userspace interface not supported(%u), try upgrading to a newer BIOS\n",

			hotfix);

		wdriver->filter_callback = NULL;

	}



	/* add in the length object we will use internally with ioctl */

	priv->req_buf_size += sizeof(u64);

	ret = set_required_buffer_size(wdev, priv->req_buf_size);

drivers/platform/x86/dell-wmi-descriptor.c

+24 −2
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ struct descriptor_priv { 
	struct list_head list;

	u32 interface_version;

	u32 size;

	u32 hotfix;

};

static int descriptor_valid = -EPROBE_DEFER;

static LIST_HEAD(wmi_list);
@@ -77,6 +78,24 @@ bool dell_wmi_get_size(u32 *size) 
}

EXPORT_SYMBOL_GPL(dell_wmi_get_size);



bool dell_wmi_get_hotfix(u32 *hotfix)

{

	struct descriptor_priv *priv;

	bool ret = false;



	mutex_lock(&list_mutex);

	priv = list_first_entry_or_null(&wmi_list,

					struct descriptor_priv,

					list);

	if (priv) {

		*hotfix = priv->hotfix;

		ret = true;

	}

	mutex_unlock(&list_mutex);

	return ret;

}

EXPORT_SYMBOL_GPL(dell_wmi_get_hotfix);



/*

 * Descriptor buffer is 128 byte long and contains:

 *
@@ -85,6 +104,7 @@ EXPORT_SYMBOL_GPL(dell_wmi_get_size); 
 * Object Signature          4       4    " WMI"

 * WMI Interface Version     8       4    <version>

 * WMI buffer length        12       4    <length>

 * WMI hotfix number        16       4    <hotfix>

 */

static int dell_wmi_descriptor_probe(struct wmi_device *wdev)

{
@@ -144,15 +164,17 @@ static int dell_wmi_descriptor_probe(struct wmi_device *wdev) 


	priv->interface_version = buffer[2];

	priv->size = buffer[3];

	priv->hotfix = buffer[4];

	ret = 0;

	dev_set_drvdata(&wdev->dev, priv);

	mutex_lock(&list_mutex);

	list_add_tail(&priv->list, &wmi_list);

	mutex_unlock(&list_mutex);



	dev_dbg(&wdev->dev, "Detected Dell WMI interface version %lu and buffer size %lu\n",

	dev_dbg(&wdev->dev, "Detected Dell WMI interface version %lu, buffer size %lu, hotfix %lu\n",

		(unsigned long) priv->interface_version,

		(unsigned long) priv->size);

		(unsigned long) priv->size,

		(unsigned long) priv->hotfix);



out:

	kfree(obj);

drivers/platform/x86/dell-wmi-descriptor.h

+1 −0
Original line number Diff line number Diff line
@@ -23,5 +23,6 @@ int dell_wmi_get_descriptor_valid(void); 


bool dell_wmi_get_interface_version(u32 *version);

bool dell_wmi_get_size(u32 *size);

bool dell_wmi_get_hotfix(u32 *hotfix);



#endif