Status
I2C Controller is enabled on I.MX8MP platform.
Supports runtime power management with clock gating.
Supports device-specific AML methods to get base clock rate through SCMI interface.
Supports pin muxing and configuration for I2C with ACPI pin resources
Changes
[Linux] Linux I2C ACPI Binding
[Linux] GCLK evaluation method in Linux:
[EDK2] Pinmux and Pinconfig support for I2C controller:
AML Code
| Code Block |
|---|
Device (I2C1)
{
Name (_HID, "NXP0104")
Name (_HRV, 0x1)
Name (_UID, 0x1)
Name (_CLK, 13)
Method (_STA)
{
Return(0xf)
}
Name (_PRS, ResourceTemplate () // _PRS: Possible Resource Settings
{
Interrupt(ResourceConsumer, Level, ActiveHigh, Exclusive) { 67 }
})
Method (_CRS, 0x0, NotSerialized)
{
Name ( RBUF, ResourceTemplate () {
MEMORY32FIXED(ReadWrite, 0x30A20000, 0x14, )
Interrupt(ResourceConsumer, Level, ActiveHigh, Exclusive) { 67 }
})
Return(RBUF)
}
Method (_PS0, 0, NotSerialized) // _PS0: Power State 0
{
SC07(_CLK, 1) // SCMI method for clock enable
}
Method (_PS3, 0, NotSerialized) // _PS3: Power State 3
{
SC07(_CLK, 0) // SCMI interface for clock gating
}
Method(GCLK, 0, NotSerialized)
{
local0 = SC06(_CLK) // SCMI interface to get clock rate
Return (local0)
}
} |
I2C Base Clock Rate
I2C controller for the IMX platform needs to know the base clock rate for the controller to configure the clock scaling factors in the controller. For the device tree, this can be specified through clock properties. There are few options available for ACPI
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