SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
Table 26-8 describes power-management features available for the multimaster HS I2C controllers.
| Feature | Registers | Description |
|---|---|---|
| Clock auto gating | I2Ci.I2C_SYSC[0] AUTOIDLE | This bit allows a local power optimization inside the module. |
| Slave idle modes | I2Ci.I2C_SYSC[4:3] IDLEMODE | Force-idle, no-idle, smart-idle, and smart-idle wakeup-capable modes are available. |
| Clock activity | I2Ci.I2C_SYSC[9:8] CLOCKACTIVITY | For configuration details, see Table 26-9. |
| Global wake-up enable | I2Ci.I2C_SYSC[2] ENAWAKEUP | This bit enables the wake-up feature at module level. |
The voltage controllers, in which the HS I2C controller is implemented, have no idle request/acknowledge mechanism. The idle modes for the voltage controllers are directly managed by the PRCM module.
| I2Ci.I2C_SYSC[9:8] CLOCKACTIVITY | Clock State When Module is in IDLE State | Features Available/Unavailable When Module is in IDLE State | |
|---|---|---|---|
| I2Ci_ICLK | I2Ci_ FCLK | ||
| 00 | OFF | OFF | Both clocks are disabled. |
| 10 | OFF | ON | Interface clock is disabled; functional clock is enabled |
| 01 | ON | OFF | Functional clock is disabled; interface clock is enabled |
| 11 | ON | ON | Both clocks are enabled. |
The PRCM module has no hardware means of reading the settings of CLOCKACTIVITY. Thus, software must ensure consistent programming between the I2C CLOCKACTIVITY and I2C clock PRCM control bits. For a description of the ClockActivity feature, see Module-Level Clock Management in Power, Reset, and Clock Management.