* Re: [PATCH] spi: set right CS polarity depend on gpiolib
2021-05-07 15:30 ` Mark Brown
@ 2021-05-08 1:01 ` 乱石
0 siblings, 0 replies; 3+ messages in thread
From: 乱石 @ 2021-05-08 1:01 UTC (permalink / raw)
To: Mark Brown; +Cc: linux-spi, linux-kernel
Hi,
在 2021/5/7 23:30, Mark Brown 写道:
> On Fri, May 07, 2021 at 10:51:17PM +0800, Liguang Zhang wrote:
>> After a kernel upgrade from 4.19 to 5.10, we found that tpm flow control
>> always causes TIMEOUT which caused by wrong CS polarity setting depend
>> on gpiolib.
>> if (spi->cs_gpiod)
>> /* polarity handled by gpiolib */
>> - gpiod_set_value_cansleep(spi->cs_gpiod, activate);
>> + gpiod_set_value_cansleep(spi->cs_gpiod, !enable);
> Whatever is going on here it doesn't seem likely that this is a problem
> in the SPI core given the widespread use of gpiod based chip selects -
> can you provide more explanation of what you're seeing here, how is the
> chip select configured, what is the hardware expectation and what
> actually ends up happening?
The arm platform is kunpeng-920, detail dsdt information here:
Device (SPI0)
{
Name (_HID, "HISI0173") // _HID: Hardware ID
Name (_ADR, Zero) // _ADR: Address
Name (_UID, Zero) // _UID: Unique ID
Name (RBUF, ResourceTemplate ()
{
GpioIo (Exclusive, PullUp, 0x0000, 0x0000,
IoRestrictionNone,
"\\_SB.GPO1", 0x00, ResourceConsumer, ,
)
{ // Pin list
0x0006
}
QWordMemory (ResourceConsumer, PosDecode, MinFixed,
MaxFixed, NonCacheable, ReadWrite,
0x0000000000000000, // Granularity
0x00000002011A0000, // Range Minimum
0x00000002011AFFFF, // Range Maximum
0x0000000000000000, // Translation Offset
0x0000000000010000, // Length
,, , AddressRangeMemory, TypeStatic)
Interrupt (ResourceConsumer, Level, ActiveHigh,
Exclusive, ,, )
{
0x000001EB,
}
})
Method (_CRS, 0, NotSerialized) // _CRS: Current Resource
Settings
{
Return (RBUF) /* \_SB_.SPI0.RBUF */
}
Name (_DSD, Package (0x02) // _DSD: Device-Specific Data
{
ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301") /*
Device Properties for _DSD */,
Package (0x03)
{
Package (0x02)
{
"reg-io-width",
0x04
},
Package (0x02)
{
"num-cs",
One
},
Package (0x02)
{
"cs-gpios",
Package (0x04)
{
SPI0,
Zero,
Zero,
Zero
}
}
}
})
}
Scope (SPI0)
{
Device (TPM)
{
Name (_ADR, Zero) // _ADR: Address
Name (_CID, Package (0x01) // _CID: Compatible ID
{
"SMO0768"
})
Name (_UID, Zero) // _UID: Unique ID
Name (_DSD, Package (0x02) // _DSD: Device-Specific Data
{
ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301") /*
Device Properties for _DSD */,
Package (0x00){}
})
Method (_CRS, 0, NotSerialized) // _CRS: Current
Resource Settings
{
Name (RBUF, ResourceTemplate ()
{
SpiSerialBusV2 (0x0000, PolarityLow,
FourWireMode, 0x08,
ControllerInitiated, 0x000F4240,
ClockPolarityLow,
ClockPhaseFirst, "\\_SB.SPI0",
0x00, ResourceConsumer, , Exclusive,
)
})
Return (RBUF) /* \_SB_.SPI0.TPM_._CRS.RBUF */
}
Method (_STA, 0, NotSerialized) // _STA: Status
{
If ((TPEN == One))
{
Return (0x0F)
}
Else
{
Return (Zero)
}
}
}
}
}
The problem I meet is:
tpm_tis_spi_init
tpm_tis_core_init
wait_startup // Timeout is occured, appear every time.
If the modification below done, probe succeed.
gpiod_set_value_cansleep(spi->cs_gpiod, !enable)
^ permalink raw reply [flat|nested] 3+ messages in thread