Re: [RFC 2/3] ACPI / scan: Fix enumeration for special UART devices

On Sat, Sep 09, 2017 at 03:46:07PM +0200, Frédéric Danis wrote:

Le 07/09/2017 à 19:25, Marcel Holtmann a écrit :

quoted

quoted

--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h

@@ -211,7 +211,7 @@ struct acpi_device_flags {

u32 of_compatible_ok:1;
u32 coherent_dma:1;
u32 cca_seen:1;
-	u32 spi_i2c_slave:1;
+	u32 serial_slave:1;
u32 reserved:19;
};

I am not an ACPI expert, but wouldn't we better have a serial_bus_slave
here. And the serial_bus_slave can be either UART or I2C? Or have a
pretty good commit message explaining why this is serial_slave only.

I will rename it.
serial_bus_slave can be either SPI, I2C or UART
(cf. http://elixir.free-electrons.com/linux/latest/source/include/acpi/acrestyp.h#L446).

Another idea would be to describe the *effect*, rather than the devices
affected, i.e. something like:

-	u32 spi_i2c_slave:1;
+	u32 parent_enumerated:1;

such that it could be extended to slaves on a non-serial bus in the
future.

Thanks,

Lukas

Hi Lukas,

quoted

quoted

quoted

--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h

@@ -211,7 +211,7 @@ struct acpi_device_flags {

	u32 of_compatible_ok:1;
	u32 coherent_dma:1;
	u32 cca_seen:1;
-	u32 spi_i2c_slave:1;
+	u32 serial_slave:1;
	u32 reserved:19;
};

I am not an ACPI expert, but wouldn't we better have a serial_bus_slave
here. And the serial_bus_slave can be either UART or I2C? Or have a
pretty good commit message explaining why this is serial_slave only.

I will rename it.
serial_bus_slave can be either SPI, I2C or UART
(cf. http://elixir.free-electrons.com/linux/latest/source/include/acpi/acrestyp.h#L446).

Another idea would be to describe the *effect*, rather than the devices
affected, i.e. something like:

-	u32 spi_i2c_slave:1;
+	u32 parent_enumerated:1;

such that it could be extended to slaves on a non-serial bus in the
future.

that might work as well. However right now I would be fine with serial_bus_slave here. Since that makes it clear that this is more than just UART devices. It is generic serial bus based devices.

Regards

Marcel