platform/x86: wmi: add WMI support to MODULE_DEVICE_TABLE()

The kernel provides the macro MODULE_DEVICE_TABLE() where driver authors
can specify their device type and their array of device_ids and thereby
trigger the generation of the appropriate MODULE_ALIAS() output. This is
opposed to having to specify one MODULE_ALIAS() for each device. The WMI
device type is currently not supported.

While using MODULE_DEVICE_TABLE() does increase the complexity as well
as spreading out the implementation across the kernel, it does come with
some benefits too;
* It makes different drivers look more similar; if you can specify the
  array of device_ids any device type specific input to MODULE_ALIAS()
  will automatically be generated for you.
* It helps each driver avoid keeping multiple versions of the same
  information in sync. That is, both the array of device_ids and the
  potential multitude of MODULE_ALIAS()'s.

Add WMI support to MODULE_DEVICE_TABLE() by adding info about struct
wmi_device_id in devicetable-offsets.c and add a WMI entry point in
file2alias.c.

The type argument for MODULE_DEVICE_TABLE(type, name) is wmi.

Suggested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index 293004499b4dbac66784e485d2e32a2ae9286d5f..99276a422e7709c9a2455fd6bd9da5a4602ff515 100644 (file)
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -225,5 +225,8 @@ int main(void)
        DEVID_FIELD(typec_device_id, svid);
        DEVID_FIELD(typec_device_id, mode);
 
+       DEVID(wmi_device_id);
+       DEVID_FIELD(wmi_device_id, guid_string);
+
        return 0;
 }

diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 4e4f03a12cc0870792c8543a0d399ed1fe90d313..6dedc31a492583ea2c2671bb7c5ed3622be2c200 100644 (file)
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1291,6 +1291,27 @@ static int do_typec_entry(const char *filename, void *symval, char *alias)
        return 1;
 }
 
+/* Looks like: wmi:guid */
+static int do_wmi_entry(const char *filename, void *symval, char *alias)
+{
+       int len;
+       DEF_FIELD_ADDR(symval, wmi_device_id, guid_string);
+
+       if (strlen(*guid_string) != UUID_STRING_LEN) {
+               warn("Invalid WMI device id 'wmi:%s' in '%s'\n",
+                               *guid_string, filename);
+               return 0;
+       }
+
+       len = snprintf(alias, ALIAS_SIZE, WMI_MODULE_PREFIX "%s", *guid_string);
+       if (len < 0 || len >= ALIAS_SIZE) {
+               warn("Could not generate all MODULE_ALIAS's in '%s'\n",
+                               filename);
+               return 0;
+       }
+       return 1;
+}
+
 /* Does namelen bytes of name exactly match the symbol? */
 static bool sym_is(const char *name, unsigned namelen, const char *symbol)
 {
@@ -1361,6 +1382,7 @@ static const struct devtable devtable[] = {
        {"fslmc", SIZE_fsl_mc_device_id, do_fsl_mc_entry},
        {"tbsvc", SIZE_tb_service_id, do_tbsvc_entry},
        {"typec", SIZE_typec_device_id, do_typec_entry},
+       {"wmi", SIZE_wmi_device_id, do_wmi_entry},
 };
 
 /* Create MODULE_ALIAS() statements.