From 92b8c540bce7b1662212dff35f503f5b1266725b Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Wed, 1 Nov 2017 14:25:27 -0500 Subject: platform/x86: dell-wmi-descriptor: split WMI descriptor into it's own driver All communication on individual GUIDs should occur in separate drivers. Allowing a driver to communicate with the bus to another GUID is just a hack that discourages drivers to adopt the bus model. The information found from the WMI descriptor driver is now exported for use by other drivers. Signed-off-by: Mario Limonciello Reviewed-by: Edward O'Callaghan Signed-off-by: Darren Hart (VMware) --- drivers/platform/x86/dell-wmi-descriptor.h | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 drivers/platform/x86/dell-wmi-descriptor.h (limited to 'drivers/platform/x86/dell-wmi-descriptor.h') diff --git a/drivers/platform/x86/dell-wmi-descriptor.h b/drivers/platform/x86/dell-wmi-descriptor.h new file mode 100644 index 000000000000..5f7b69c2c83a --- /dev/null +++ b/drivers/platform/x86/dell-wmi-descriptor.h @@ -0,0 +1,21 @@ +/* + * Dell WMI descriptor driver + * + * Copyright (c) 2017 Dell Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef _DELL_WMI_DESCRIPTOR_H_ +#define _DELL_WMI_DESCRIPTOR_H_ + +#include + +#define DELL_WMI_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492" + +bool dell_wmi_get_interface_version(u32 *version); +bool dell_wmi_get_size(u32 *size); + +#endif -- cgit v1.2.3-59-g8ed1b From 868b8d33f91e431b1961a35baa6b5022639067f3 Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Thu, 9 Nov 2017 11:49:10 -0600 Subject: platform/x86: dell-*wmi*: Relay failed initial probe to dependent drivers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit dell-wmi and dell-smbios-wmi are dependent upon dell-wmi-descriptor finishing probe successfully to probe themselves. Currently if dell-wmi-descriptor fails probing in a non-recoverable way (such as invalid header) dell-wmi and dell-smbios-wmi will continue to try to redo probing due to deferred probing. To solve this have the dependent drivers query the dell-wmi-descriptor driver whether the descriptor has been determined valid. The possible results are: -ENODEV: Descriptor GUID missing from WMI bus -EPROBE_DEFER: Descriptor not yet probed, dependent driver should wait and use deferred probing < 0: Descriptor probed, invalid. Dependent driver should return an error. 0: Successful descriptor probe, dependent driver can continue Successful descriptor probe still doesn't mean that the descriptor driver is necessarily bound at the time of initialization of dependent driver. Userspace can unbind the driver, so all methods used from driver should still be verified to return success values otherwise deferred probing be used. Signed-off-by: Mario Limonciello Reviewed-by: Pali Rohár Signed-off-by: Darren Hart (VMware) --- drivers/platform/x86/dell-smbios-wmi.c | 5 +++-- drivers/platform/x86/dell-wmi-descriptor.c | 16 ++++++++++++++++ drivers/platform/x86/dell-wmi-descriptor.h | 8 +++++++- drivers/platform/x86/dell-wmi.c | 6 ++++-- 4 files changed, 30 insertions(+), 5 deletions(-) (limited to 'drivers/platform/x86/dell-wmi-descriptor.h') diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell-smbios-wmi.c index 5cf9b13ce6e6..0cab1f9c35af 100644 --- a/drivers/platform/x86/dell-smbios-wmi.c +++ b/drivers/platform/x86/dell-smbios-wmi.c @@ -151,8 +151,9 @@ static int dell_smbios_wmi_probe(struct wmi_device *wdev) int count; int ret; - if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID)) - return -ENODEV; + ret = dell_wmi_get_descriptor_valid(); + if (ret) + return ret; priv = devm_kzalloc(&wdev->dev, sizeof(struct wmi_smbios_priv), GFP_KERNEL); diff --git a/drivers/platform/x86/dell-wmi-descriptor.c b/drivers/platform/x86/dell-wmi-descriptor.c index 28ef5f37cfbf..4dfef1f53481 100644 --- a/drivers/platform/x86/dell-wmi-descriptor.c +++ b/drivers/platform/x86/dell-wmi-descriptor.c @@ -21,14 +21,26 @@ #include #include "dell-wmi-descriptor.h" +#define DELL_WMI_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492" + struct descriptor_priv { struct list_head list; u32 interface_version; u32 size; }; +static int descriptor_valid = -EPROBE_DEFER; static LIST_HEAD(wmi_list); static DEFINE_MUTEX(list_mutex); +int dell_wmi_get_descriptor_valid(void) +{ + if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID)) + return -ENODEV; + + return descriptor_valid; +} +EXPORT_SYMBOL_GPL(dell_wmi_get_descriptor_valid); + bool dell_wmi_get_interface_version(u32 *version) { struct descriptor_priv *priv; @@ -91,6 +103,7 @@ static int dell_wmi_descriptor_probe(struct wmi_device *wdev) if (obj->type != ACPI_TYPE_BUFFER) { dev_err(&wdev->dev, "Dell descriptor has wrong type\n"); ret = -EINVAL; + descriptor_valid = ret; goto out; } @@ -102,6 +115,7 @@ static int dell_wmi_descriptor_probe(struct wmi_device *wdev) "Dell descriptor buffer has unexpected length (%d)\n", obj->buffer.length); ret = -EINVAL; + descriptor_valid = ret; goto out; } @@ -111,8 +125,10 @@ static int dell_wmi_descriptor_probe(struct wmi_device *wdev) dev_err(&wdev->dev, "Dell descriptor buffer has invalid signature (%8ph)\n", buffer); ret = -EINVAL; + descriptor_valid = ret; goto out; } + descriptor_valid = 0; if (buffer[2] != 0 && buffer[2] != 1) dev_warn(&wdev->dev, "Dell descriptor buffer has unknown version (%lu)\n", diff --git a/drivers/platform/x86/dell-wmi-descriptor.h b/drivers/platform/x86/dell-wmi-descriptor.h index 5f7b69c2c83a..1e8cb96ffd78 100644 --- a/drivers/platform/x86/dell-wmi-descriptor.h +++ b/drivers/platform/x86/dell-wmi-descriptor.h @@ -13,7 +13,13 @@ #include -#define DELL_WMI_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492" +/* possible return values: + * -ENODEV: Descriptor GUID missing from WMI bus + * -EPROBE_DEFER: probing for dell-wmi-descriptor not yet run + * 0: valid descriptor, successfully probed + * < 0: invalid descriptor, don't probe dependent devices + */ +int dell_wmi_get_descriptor_valid(void); bool dell_wmi_get_interface_version(u32 *version); bool dell_wmi_get_size(u32 *size); diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c index 54321080a30d..39d2f4518483 100644 --- a/drivers/platform/x86/dell-wmi.c +++ b/drivers/platform/x86/dell-wmi.c @@ -655,9 +655,11 @@ static int dell_wmi_events_set_enabled(bool enable) static int dell_wmi_probe(struct wmi_device *wdev) { struct dell_wmi_priv *priv; + int ret; - if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID)) - return -ENODEV; + ret = dell_wmi_get_descriptor_valid(); + if (ret) + return ret; priv = devm_kzalloc( &wdev->dev, sizeof(struct dell_wmi_priv), GFP_KERNEL); -- cgit v1.2.3-59-g8ed1b From 4255c30fe88ee3cc99bbeac7974db27e4217a497 Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Thu, 16 Nov 2017 22:13:12 -0600 Subject: 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: Girish Prakash Signed-off-by: Mario Limonciello Signed-off-by: Darren Hart (VMware) --- drivers/platform/x86/dell-smbios-wmi.c | 13 +++++++++++++ drivers/platform/x86/dell-wmi-descriptor.c | 26 ++++++++++++++++++++++++-- drivers/platform/x86/dell-wmi-descriptor.h | 1 + 3 files changed, 38 insertions(+), 2 deletions(-) (limited to 'drivers/platform/x86/dell-wmi-descriptor.h') diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell-smbios-wmi.c index 0cab1f9c35af..609557aa5868 100644 --- a/drivers/platform/x86/dell-smbios-wmi.c +++ b/drivers/platform/x86/dell-smbios-wmi.c @@ -147,7 +147,10 @@ fail_smbios_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); diff --git a/drivers/platform/x86/dell-wmi-descriptor.c b/drivers/platform/x86/dell-wmi-descriptor.c index 4dfef1f53481..072821aa47fc 100644 --- a/drivers/platform/x86/dell-wmi-descriptor.c +++ b/drivers/platform/x86/dell-wmi-descriptor.c @@ -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 * WMI buffer length 12 4 + * WMI hotfix number 16 4 */ 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); diff --git a/drivers/platform/x86/dell-wmi-descriptor.h b/drivers/platform/x86/dell-wmi-descriptor.h index 1e8cb96ffd78..a6123a4d06a7 100644 --- a/drivers/platform/x86/dell-wmi-descriptor.h +++ b/drivers/platform/x86/dell-wmi-descriptor.h @@ -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 -- cgit v1.2.3-59-g8ed1b