Re: [RFC] platform/x86: hp-wmi: make hp_wmi_perform_query() work with certain devices

[Bedant Patnaik <bedant.patnaik@xxxxxxxxx>]

>From 59c10c3007e52694318324fc5e9cfbce83533491 Mon Sep 17 00:00:00 2001
From: Bedant Patnaik <bedant.patnaik@xxxxxxxxx>
Date: Tue, 7 Jun 2022 23:30:57 +0530
Subject: [PATCH] Use zero insize parameter only when supported

be9d73e64957bbd31ee9a0d11adc0f720974c558 ("platform/x86: hp-wmi: Fix 0x05 error code reported by several WMI calls")
and 12b19f14a21a2ee6348825d95b642ef2cd16794f ("platform/x86: hp-wmi: Fix hp_wmi_read_int() reporting error (0x05)")
cause ACPI BIOS Error (bug): Attempt to CreateField of length zero (20211217/dsopcode-133) because of the ACPI
method HWMC, which unconditionally creates a Field of size (insize*8) bits:
	CreateField (Arg1, 0x80, (Local5 * 0x08), DAIN)
In cases where args->insize = 0, the Field size is 0, resulting in an error.
Fix: use zero insize only if 0x5 error code is returned

Tested on Omen 15 AMD (2020) board ID: 8786.

Signed-off-by: Bedant Patnaik <bedant.patnaik@xxxxxxxxx>
---
 drivers/platform/x86/hp-wmi.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/platform/x86/hp-wmi.c b/drivers/platform/x86/hp-wmi.c
index 7a54191f0..809294e36 100644
--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -38,6 +38,7 @@ MODULE_ALIAS("wmi:5FB7F034-2C63-45e9-BE91-3D44E2C707E4");
 #define HPWMI_EVENT_GUID "95F24279-4D7B-4334-9387-ACCDC67EF61C"
 #define HPWMI_BIOS_GUID "5FB7F034-2C63-45e9-BE91-3D44E2C707E4"
 #define HP_OMEN_EC_THERMAL_PROFILE_OFFSET 0x95
+#define zero_if_sup(tmp) (zero_insize_support?0:sizeof(tmp)) // use when zero insize is required
 
 /* DMI board names of devices that should use the omen specific path for
  * thermal profiles.
@@ -220,6 +221,7 @@ static struct input_dev *hp_wmi_input_dev;
 static struct platform_device *hp_wmi_platform_dev;
 static struct platform_profile_handler platform_profile_handler;
 static bool platform_profile_support;
+static bool zero_insize_support;
 
 static struct rfkill *wifi_rfkill;
 static struct rfkill *bluetooth_rfkill;
@@ -374,7 +376,7 @@ static int hp_wmi_read_int(int query)
 	int val = 0, ret;
 
 	ret = hp_wmi_perform_query(query, HPWMI_READ, &val,
-				   0, sizeof(val));
+				   zero_if_sup(val), sizeof(val));
 
 	if (ret)
 		return ret < 0 ? ret : -EINVAL;
@@ -410,7 +412,8 @@ static int hp_wmi_get_tablet_mode(void)
 		return -ENODEV;
 
 	ret = hp_wmi_perform_query(HPWMI_SYSTEM_DEVICE_MODE, HPWMI_READ,
-				   system_device_mode, 0, sizeof(system_device_mode));
+				   system_device_mode, zero_if_sup(system_device_mode),
+				   sizeof(system_device_mode));
 	if (ret < 0)
 		return ret;
 
@@ -497,7 +500,7 @@ static int hp_wmi_fan_speed_max_get(void)
 	int val = 0, ret;
 
 	ret = hp_wmi_perform_query(HPWMI_FAN_SPEED_MAX_GET_QUERY, HPWMI_GM,
-				   &val, 0, sizeof(val));
+				   &val, zero_if_sup(val), sizeof(val));
 
 	if (ret)
 		return ret < 0 ? ret : -EINVAL;
@@ -509,7 +512,7 @@ static int __init hp_wmi_bios_2008_later(void)
 {
 	int state = 0;
 	int ret = hp_wmi_perform_query(HPWMI_FEATURE_QUERY, HPWMI_READ, &state,
-				       0, sizeof(state));
+				       zero_if_sup(state), sizeof(state));
 	if (!ret)
 		return 1;
 
@@ -520,7 +523,7 @@ static int __init hp_wmi_bios_2009_later(void)
 {
 	u8 state[128];
 	int ret = hp_wmi_perform_query(HPWMI_FEATURE2_QUERY, HPWMI_READ, &state,
-				       0, sizeof(state));
+				       zero_if_sup(state), sizeof(state));
 	if (!ret)
 		return 1;
 
@@ -598,7 +601,7 @@ static int hp_wmi_rfkill2_refresh(void)
 	int err, i;
 
 	err = hp_wmi_perform_query(HPWMI_WIRELESS2_QUERY, HPWMI_READ, &state,
-				   0, sizeof(state));
+				   zero_if_sup(state), sizeof(state));
 	if (err)
 		return err;
 
@@ -1007,7 +1010,7 @@ static int __init hp_wmi_rfkill2_setup(struct platform_device *device)
 	int err, i;
 
 	err = hp_wmi_perform_query(HPWMI_WIRELESS2_QUERY, HPWMI_READ, &state,
-				   0, sizeof(state));
+				   zero_if_sup(state), sizeof(state));
 	if (err)
 		return err < 0 ? err : -EINVAL;
 
@@ -1483,11 +1486,15 @@ static int __init hp_wmi_init(void)
 {
 	int event_capable = wmi_has_guid(HPWMI_EVENT_GUID);
 	int bios_capable = wmi_has_guid(HPWMI_BIOS_GUID);
-	int err;
+	int err, tmp = 0;
 
 	if (!bios_capable && !event_capable)
 		return -ENODEV;
 
+	if (hp_wmi_perform_query(HPWMI_HARDWARE_QUERY, HPWMI_READ, &tmp,
+				 sizeof(tmp), sizeof(tmp)) == HPWMI_RET_INVALID_PARAMETERS)
+		zero_insize_support = true;
+
 	if (event_capable) {
 		err = hp_wmi_input_setup();
 		if (err)
-- 
2.36.1