Mediatek Driver 2023 -

But in the kernel source tree, deep inside drivers/misc/mediatek/conn_mgr/ , there remains a patch file named:

It was a zombie driver. Alive, breathing, and eating battery. At 8:13 AM, Lena joined a video call with MediaTek’s driver team in Hsinchu. On the screen: a balding senior architect named Dr. Chen, who had authored the original sleep controller in 2019.

She traced the logic. The mtk_sleepctl driver was supposed to suspend the display pipeline when the screen turned off. But in the 2023 revision, a junior engineer had added a “performance boost” for the new GPU: a function called mtk_disp_qos_boost() that never released its power-management Quality of Service (PM_QoS) vote. mediatek driver 2023

/* * MediaTek Unified Sleep Controller v3.2 (2023-01-15) * Legacy support for MT6879, MT6895, and MT6983. * Author: mtk_driver_team * WARNING: Do not modify without internal approval. */ Lena almost closed it. Legacy support was usually harmless. But a comment near line 1,204 made her stop scrolling:

For the next 14 hours, Lena reverse-engineered the driver’s state machine. She found that mtk_disp_qos_boost() was called by a display IRQ that never fired the corresponding release. The fix was six lines of code: But in the kernel source tree, deep inside

“Your driver is melting batteries,” Lena replied.

/* FIXME: PM_QoS voting mismatch if DVFS table > 4 cores. -SJL, 2022-12-01 */ The fix note was from December 2022—just weeks before the driver was finalized. And it was never resolved. On the screen: a balding senior architect named Dr

She opened the driver source tree—a sprawling 4.2-gigabyte labyrinth of C code that MediaTek had provided in Q1 2023. Buried inside drivers/misc/mediatek/conn_mgr/ was a module no one on her team had touched: mtk_sleepctl_2023.c . The file header read: