serial: extend compile-test coverage

Allow more drivers to be compile tested more easily, for example, when
doing subsystem-wide changes.

Verified on X86_64 as well as arm, powerpc and m68k with minimal configs
in order to catch missing implicit build dependencies (e.g. MAILBOX for
SERIAL_TEGRA_TCU).

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210422080211.29326-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/Kconfig

@@ -403,7 +403,8 @@ config SERIAL_8250_RT288X
 
 config SERIAL_8250_OMAP
 	tristate "Support for OMAP internal UART (8250 based driver)"
-	depends on SERIAL_8250 && (ARCH_OMAP2PLUS || ARCH_K3)
+	depends on SERIAL_8250
+	depends on ARCH_OMAP2PLUS || ARCH_K3 || COMPILE_TEST
 	help
 	  If you have a machine based on an Texas Instruments OMAP CPU you
 	  can enable its onboard serial ports by enabling this option.
@@ -439,7 +440,8 @@ config SERIAL_8250_LPC18XX
 
 config SERIAL_8250_MT6577
 	tristate "Mediatek serial port support"
-	depends on SERIAL_8250 && ARCH_MEDIATEK
+	depends on SERIAL_8250
+	depends on ARCH_MEDIATEK || COMPILE_TEST
 	help
 	  If you have a Mediatek based board and want to use the
 	  serial port, say Y to this option. If unsure, say N.

drivers/tty/serial/Kconfig

@@ -20,7 +20,7 @@ comment "Non-8250 serial port support"
 
 config SERIAL_AMBA_PL010
 	tristate "ARM AMBA PL010 serial port support"
-	depends on ARM_AMBA
+	depends on ARM_AMBA || COMPILE_TEST
 	select SERIAL_CORE
 	help
 	  This selects the ARM(R) AMBA(R) PrimeCell PL010 UART.  If you have
@@ -198,7 +198,7 @@ config SERIAL_KGDB_NMI
 
 config SERIAL_MESON
 	tristate "Meson serial port support"
-	depends on ARCH_MESON
+	depends on ARCH_MESON || COMPILE_TEST
 	select SERIAL_CORE
 	help
 	  This enables the driver for the on-chip UARTs of the Amlogic
@@ -278,7 +278,7 @@ config SERIAL_SAMSUNG_CONSOLE
 
 config SERIAL_TEGRA
 	tristate "NVIDIA Tegra20/30 SoC serial controller"
-	depends on ARCH_TEGRA && TEGRA20_APB_DMA
+	depends on (ARCH_TEGRA && TEGRA20_APB_DMA) || COMPILE_TEST
 	select SERIAL_CORE
 	help
 	  Support for the on-chip UARTs on the NVIDIA Tegra series SOCs
@@ -289,7 +289,8 @@ config SERIAL_TEGRA
 
 config SERIAL_TEGRA_TCU
 	tristate "NVIDIA Tegra Combined UART"
-	depends on ARCH_TEGRA && TEGRA_HSP_MBOX
+	depends on MAILBOX
+	depends on (ARCH_TEGRA && TEGRA_HSP_MBOX) || COMPILE_TEST
 	select SERIAL_CORE
 	help
 	  Support for the mailbox-based TCU (Tegra Combined UART) serial port.
@@ -852,7 +853,8 @@ config SERIAL_MPC52xx_CONSOLE_BAUD
 
 config SERIAL_ICOM
 	tristate "IBM Multiport Serial Adapter"
-	depends on PCI && PPC_PSERIES
+	depends on PCI
+	depends on PPC_PSERIES || COMPILE_TEST
 	select SERIAL_CORE
 	select FW_LOADER
 	help
@@ -921,7 +923,7 @@ config SERIAL_JSM
 
 config SERIAL_MSM
 	tristate "MSM on-chip serial port support"
-	depends on ARCH_QCOM
+	depends on ARCH_QCOM || COMPILE_TEST
 	select SERIAL_CORE
 
 config SERIAL_MSM_CONSOLE
@@ -947,7 +949,7 @@ config SERIAL_QCOM_GENI_CONSOLE
 
 config SERIAL_VT8500
 	bool "VIA VT8500 on-chip serial port support"
-	depends on ARCH_VT8500
+	depends on ARCH_VT8500 || COMPILE_TEST
 	select SERIAL_CORE
 
 config SERIAL_VT8500_CONSOLE
@@ -957,7 +959,7 @@ config SERIAL_VT8500_CONSOLE
 
 config SERIAL_OMAP
 	tristate "OMAP serial port support"
-	depends on ARCH_OMAP2PLUS
+	depends on ARCH_OMAP2PLUS || COMPILE_TEST
 	select SERIAL_CORE
 	help
 	  If you have a machine based on an Texas Instruments OMAP CPU you