[PATCH v10 4/4] HID: hid-msi: Add Rumble Intensity Attributes

["Derek J. Clark" <derekjohn.clark@gmail.com>]

Adds intensity adjustment for the left and right rumble motors.

Claude was used during the reverse-engineering data gathering for this
feature done by Zhouwang Huang. As the code had already been affected,
I used Claude to create the initial framing for the feature, then did
manual cleanup of the _show and _store functions afterwards to fix bugs
and keep the coding style consistent. Claude was also used as an initial
reviewer of this patch.

Assisted-by: Claude:claude-sonnet-4-6
Co-developed-by: Zhouwang Huang <honjow311@gmail.com>
Signed-off-by: Zhouwang Huang <honjow311@gmail.com>
Signed-off-by: Derek J. Clark <derekjohn.clark@gmail.com>
---
v7:
  - Match on write address for rumble reports to prevent late ACK
    from causing synchronization errors.
  - Use spinlock for read/write profile_pending.
  - Use smp_[store_release|load_acquire] pattern for checking
    gamepad_registered to avoid possible races during teardown.
  - Use struct for rumble reports.
v6:
  - Make all timeouts 25ms to ensure at least 2 jiffies in a 100Hz
    config.
  - Add spinlock_irqsave for read/write access on rumble_intensity
    variables.
  - Gate all attribute show/store functions with gamepad_registered.
v5:
  - Remove mkey related changes.
v2:
  - Use pending_profile and sync to rom mutexes.
---
 drivers/hid/hid-msi.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-msi.c b/drivers/hid/hid-msi.c
index 96710d80543d4..17b0707ecd46d 100644
--- a/drivers/hid/hid-msi.c
+++ b/drivers/hid/hid-msi.c
@@ -266,6 +266,11 @@ static const u16 button_mapping_addr_new[] = {
 static const u16 rgb_addr_old = 0x01fa;
 static const u16 rgb_addr_new = 0x024a;
 
+static const u16 rumble_addr[] = {
+	0x0022,  /* left  */
+	0x0023,  /* right */
+};
+
 struct claw_command_report {
 	u8 report_id;
 	u8 padding[2];
@@ -308,6 +313,12 @@ struct claw_rgb_report {
 	struct rgb_frame zone_data;
 } __packed;
 
+struct claw_rumble_report {
+	struct claw_profile_report;
+	u8 padding;
+	u8 intensity;
+} __packed;
+
 struct claw_drvdata {
 	/* MCU General Variables */
 	enum claw_profile_ack_pending profile_pending;
@@ -332,8 +343,12 @@ struct claw_drvdata {
 	enum claw_gamepad_mode_index gamepad_mode;
 	u8 m1_codes[CLAW_KEYS_MAX];
 	u8 m2_codes[CLAW_KEYS_MAX];
-	spinlock_t mode_lock; /* Lock for mode data read/write */
+	u8 rumble_intensity_right;
+	u8 rumble_intensity_left;
 	const u16 *bmap_addr;
+	spinlock_t rumble_lock; /* lock for rumble_intensity read/write */
+	spinlock_t mode_lock; /* Lock for mode data read/write */
+	bool rumble_support;
 	bool gp_registered;
 	bool bmap_support;
 
-- 
2.53.0