[PATCH AUTOSEL 6.17-6.12] HID: pidff: PERMISSIVE_CONTROL quirk autodetection

[Sasha Levin <sashal@kernel.org>]

From: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>

[ Upstream commit c2dc9f0b368c08c34674311cf78407718d5715a7 ]

Fixes force feedback for devices built with MMOS firmware and many more
not yet detected devices.

Update quirks mask debug message to always contain all 32 bits of data.

Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

YES

Why this is a good stable backport
- Fixes real user-visible breakage: enables force feedback on devices
  with MMOS firmware and other devices misreporting PID_DEVICE_CONTROL’s
  logical_minimum (previously failed to initialize FF).
- Small, contained change in HID PID FF driver; no architectural changes
  or cross‑subsystem impacts.
- Risk is low: the new behavior only relaxes a check if the strict path
  fails, and only for the specific Device Control field; otherwise
  behavior remains identical.
- Improves diagnostics (full 32‑bit quirks mask) without functional side
  effects.
- Aligns with stable rules: important bugfix, minimal risk, confined to
  HID/PIDFF.

What changes, concretely
- Autodetect and set PERMISSIVE_CONTROL only when needed:
  - Before: Device Control lookup was strict unless the quirk was pre-
    specified (e.g., via device ID). If logical_minimum != 1, driver
    failed with “device control field not found”.
  - After: Try strict lookup first; if not found, set
    `HID_PIDFF_QUIRK_PERMISSIVE_CONTROL` and retry without enforcing
    min==1. This allows devices with non‑conforming descriptors to work
    without hardcoding IDs.
- Debug formatting improvement: print all 32 bits of the quirks mask.

Relevant code references (current tree)
- Device Control lookup currently enforces min==1 unless the quirk is
  already set:
  - drivers/hid/usbhid/hid-pidff.c:1135
    - `pidff->device_control = pidff_find_special_field(...,
      PID_DEVICE_CONTROL_ARRAY, !(pidff->quirks &
      HID_PIDFF_QUIRK_PERMISSIVE_CONTROL));`
  - The change will:
    - First call with `enforce_min=1`, then if null:
      - `pr_debug("Setting PERMISSIVE_CONTROL quirk");`
      - `pidff->quirks |= HID_PIDFF_QUIRK_PERMISSIVE_CONTROL;`
      - Retry with `enforce_min=0`.
  - Safety: If the usage isn’t present at all, the second lookup still
    returns NULL and the function returns error exactly as before.
- Quirk definition already exists:
  - drivers/hid/usbhid/hid-pidff.h:16
    - `#define HID_PIDFF_QUIRK_PERMISSIVE_CONTROL BIT(2)`
- Quirks debug formatting to widen to 8 hex digits:
  - drivers/hid/usbhid/hid-pidff.c:1477
    - Currently: `hid_dbg(dev, "Active quirks mask: 0x%x\n",
      pidff->quirks);`
    - Change to: `0x%08x` (formatting only, no logic impact).

Compatibility and dependencies
- Depends on the existing quirk bit and infrastructure (already present
  since “HID: pidff: Add PERMISSIVE_CONTROL quirk”; this is in-tree with
  Signed-off-by: Sasha Levin, so it has been flowing into stable).
- Interacts safely with the more recent fix to Device Control handling:
  - “HID: pidff: Fix set_device_control()” ensures correct 1‑based
    indexing and guards against missing fields; the autodetection does
    not invalidate those fixes.

Regression risk assessment
- Previously working devices (strict path succeeds) are unchanged.
- Previously non-working devices (strict path fails) now work via a
  guarded fallback; without the usage present, behavior remains
  identical (fail).
- The quirk only changes acceptance of the Device Control field; no
  other code paths are altered.

Conclusion
- This is a targeted, low-risk fix that unlocks FF functionality for a
  notable set of devices without broad side effects. It’s well-suited
  for backporting to stable trees that already carry the
  PERMISSIVE_CONTROL quirk.

 drivers/hid/usbhid/hid-pidff.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index c6b4f61e535d5..711eefff853bb 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -1151,8 +1151,16 @@ static int pidff_find_special_fields(struct pidff_device *pidff)
 					 PID_DIRECTION, 0);
 	pidff->device_control =
 		pidff_find_special_field(pidff->reports[PID_DEVICE_CONTROL],
-			PID_DEVICE_CONTROL_ARRAY,
-			!(pidff->quirks & HID_PIDFF_QUIRK_PERMISSIVE_CONTROL));
+			PID_DEVICE_CONTROL_ARRAY, 1);
+
+	/* Detect and set permissive control quirk */
+	if (!pidff->device_control) {
+		pr_debug("Setting PERMISSIVE_CONTROL quirk\n");
+		pidff->quirks |= HID_PIDFF_QUIRK_PERMISSIVE_CONTROL;
+		pidff->device_control = pidff_find_special_field(
+			pidff->reports[PID_DEVICE_CONTROL],
+			PID_DEVICE_CONTROL_ARRAY, 0);
+	}
 
 	pidff->block_load_status =
 		pidff_find_special_field(pidff->reports[PID_BLOCK_LOAD],
@@ -1492,7 +1500,7 @@ int hid_pidff_init_with_quirks(struct hid_device *hid, u32 initial_quirks)
 	ff->playback = pidff_playback;
 
 	hid_info(dev, "Force feedback for USB HID PID devices by Anssi Hannula <anssi.hannula@gmail.com>\n");
-	hid_dbg(dev, "Active quirks mask: 0x%x\n", pidff->quirks);
+	hid_dbg(dev, "Active quirks mask: 0x%08x\n", pidff->quirks);
 
 	hid_device_io_stop(hid);
 
-- 
2.51.0