5 files changed, 105 insertions, 33 deletions
diff --git a/drivers/platform/cznic/Kconfig b/drivers/platform/cznic/Kconfig
index cb0d4d686d8a..49c383eb6785 100644
--- a/drivers/platform/cznic/Kconfig
+++ b/drivers/platform/cznic/Kconfig
@@ -16,35 +16,65 @@ config TURRIS_OMNIA_MCU
 	tristate "Turris Omnia MCU driver"
 	depends on MACH_ARMADA_38X || COMPILE_TEST
 	depends on I2C
-	depends on OF
-	depends on WATCHDOG
-	depends on GPIOLIB
-	depends on HW_RANDOM
-	depends on RTC_CLASS
-	depends on WATCHDOG_CORE
-	select GPIOLIB_IRQCHIP
 	help
 	  Say Y here to add support for the features implemented by the
 	  microcontroller on the CZ.NIC's Turris Omnia SOHO router.
-	  The features include:
-	  - board poweroff into true low power mode (with voltage regulators
-	    disabled) and the ability to configure wake up from this mode (via
-	    rtcwake)
-	  - true random number generator (if available on the MCU)
-	  - MCU watchdog
-	  - GPIO pins
-	    - to get front button press events (the front button can be
-	      configured either to generate press events to the CPU or to change
-	      front LEDs panel brightness)
-	    - to enable / disable USB port voltage regulators and to detect
-	      USB overcurrent
-	    - to detect MiniPCIe / mSATA card presence in MiniPCIe port 0
-	    - to configure resets of various peripherals on board revisions 32+
-	    - to enable / disable the VHV voltage regulator to the SOC in order
-	      to be able to program SOC's OTP on board revisions 32+
-	    - to get input from the LED output pins of the WAN ethernet PHY, LAN
-	      switch and MiniPCIe ports
+	  This option only enables the core part of the driver. Specific
+	  features can be enabled by subsequent config options.
 	  To compile this driver as a module, choose M here; the module will be
 	  called turris-omnia-mcu.
 
+if TURRIS_OMNIA_MCU
+
+config TURRIS_OMNIA_MCU_GPIO
+	bool "Turris Omnia MCU GPIOs"
+	default y
+	depends on GPIOLIB
+	depends on OF
+	select GPIOLIB_IRQCHIP
+	help
+	  Say Y here to add support for controlling MCU GPIO pins and receiving
+	  MCU interrupts on CZ.NIC's Turris Omnia.
+	  This enables you to
+	  - get front button press events (the front button can be configured
+	    either to generate press events to the CPU or to change front LEDs
+	    panel brightness),
+	  - enable / disable USB port voltage regulators and to detect USB
+	    overcurrent,
+	  - detect MiniPCIe / mSATA card presence in MiniPCIe port 0,
+	  - configure resets of various peripherals on board revisions 32+,
+	  - enable / disable the VHV voltage regulator to the SOC in order to be
+	    able to program SOC's OTP on board revisions 32+,
+	  - get input from the LED output pins of the WAN ethernet PHY, LAN
+	    switch and MiniPCIe ports.
+
+config TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
+	bool "Turris Omnia MCU system off and RTC wakeup"
+	default y
+	depends on RTC_CLASS
+	help
+	  Say Y here to add support for CZ.NIC's Turris Omnia board poweroff
+	  into true low power mode (with voltage regulators disabled) and the
+	  ability to configure wake up from this mode (via rtcwake).
+
+config TURRIS_OMNIA_MCU_WATCHDOG
+	bool "Turris Omnia MCU watchdog"
+	default y
+	depends on WATCHDOG
+	select WATCHDOG_CORE
+	help
+	  Say Y here to add support for watchdog provided by CZ.NIC's Turris
+	  Omnia MCU.
+
+config TURRIS_OMNIA_MCU_TRNG
+	bool "Turris Omnia MCU true random number generator"
+	default y
+	depends on TURRIS_OMNIA_MCU_GPIO
+	depends on HW_RANDOM=y || HW_RANDOM=TURRIS_OMNIA_MCU
+	help
+	  Say Y here to add support for the true random number generator
+	  provided by CZ.NIC's Turris Omnia MCU.
+
+endif # TURRIS_OMNIA_MCU
+
 endif # CZNIC_PLATFORMS
diff --git a/drivers/platform/cznic/Makefile b/drivers/platform/cznic/Makefile
index eae4c6b341ff..ce6d997f34d6 100644
--- a/drivers/platform/cznic/Makefile
+++ b/drivers/platform/cznic/Makefile
@@ -2,7 +2,7 @@
 
 obj-$(CONFIG_TURRIS_OMNIA_MCU)	+= turris-omnia-mcu.o
 turris-omnia-mcu-y		:= turris-omnia-mcu-base.o
-turris-omnia-mcu-y		+= turris-omnia-mcu-gpio.o
-turris-omnia-mcu-y		+= turris-omnia-mcu-sys-off-wakeup.o
-turris-omnia-mcu-y		+= turris-omnia-mcu-trng.o
-turris-omnia-mcu-y		+= turris-omnia-mcu-watchdog.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_GPIO)		+= turris-omnia-mcu-gpio.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP)	+= turris-omnia-mcu-sys-off-wakeup.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_TRNG)		+= turris-omnia-mcu-trng.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_WATCHDOG)		+= turris-omnia-mcu-watchdog.o
diff --git a/drivers/platform/cznic/turris-omnia-mcu-base.c b/drivers/platform/cznic/turris-omnia-mcu-base.c
index c68a7a84a951..58f9afae2867 100644
--- a/drivers/platform/cznic/turris-omnia-mcu-base.c
+++ b/drivers/platform/cznic/turris-omnia-mcu-base.c
@@ -197,8 +197,12 @@ static const struct attribute_group omnia_mcu_base_group = {
 
 static const struct attribute_group *omnia_mcu_groups[] = {
 	&omnia_mcu_base_group,
+#ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
 	&omnia_mcu_gpio_group,
+#endif
+#ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
 	&omnia_mcu_poweroff_group,
+#endif
 	NULL
 };
 
diff --git a/drivers/platform/cznic/turris-omnia-mcu-trng.c b/drivers/platform/cznic/turris-omnia-mcu-trng.c
index ad953fb3c37a..9a1d9292dc9a 100644
--- a/drivers/platform/cznic/turris-omnia-mcu-trng.c
+++ b/drivers/platform/cznic/turris-omnia-mcu-trng.c
@@ -70,8 +70,8 @@ int omnia_mcu_register_trng(struct omnia_mcu *mcu)
 
 	irq_idx = omnia_int_to_gpio_idx[__bf_shf(OMNIA_INT_TRNG)];
 	irq = gpiod_to_irq(gpio_device_get_desc(mcu->gc.gpiodev, irq_idx));
-	if (!irq)
-		return dev_err_probe(dev, -ENXIO, "Cannot get TRNG IRQ\n");
+	if (irq < 0)
+		return dev_err_probe(dev, irq, "Cannot get TRNG IRQ\n");
 
 	/*
 	 * If someone else cleared the TRNG interrupt but did not read the
diff --git a/drivers/platform/cznic/turris-omnia-mcu.h b/drivers/platform/cznic/turris-omnia-mcu.h
index 2ca56ae13aa9..fed0d357fea3 100644
--- a/drivers/platform/cznic/turris-omnia-mcu.h
+++ b/drivers/platform/cznic/turris-omnia-mcu.h
@@ -33,6 +33,7 @@ struct omnia_mcu {
 	u8 board_first_mac[ETH_ALEN];
 	u8 board_revision;
 
+#ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
 	/* GPIO chip */
 	struct gpio_chip gc;
 	struct mutex lock;
@@ -41,18 +42,25 @@ struct omnia_mcu {
 	struct delayed_work button_release_emul_work;
 	unsigned long last_status;
 	bool button_pressed_emul;
+#endif
 
+#ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
 	/* RTC device for configuring wake-up */
 	struct rtc_device *rtcdev;
 	u32 rtc_alarm;
 	bool front_button_poweron;
+#endif
 
+#ifdef CONFIG_TURRIS_OMNIA_MCU_WATCHDOG
 	/* MCU watchdog */
 	struct watchdog_device wdt;
+#endif
 
+#ifdef CONFIG_TURRIS_OMNIA_MCU_TRNG
 	/* true random number generator */
 	struct hwrng trng;
 	struct completion trng_entropy_ready;
+#endif
 };
 
 int omnia_cmd_write_read(const struct i2c_client *client,
@@ -182,13 +190,43 @@ static inline int omnia_cmd_read_u8(const struct i2c_client *client, u8 cmd,
 	return omnia_cmd_read(client, cmd, reply, sizeof(*reply));
 }
 
+#ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
 extern const u8 omnia_int_to_gpio_idx[32];
 extern const struct attribute_group omnia_mcu_gpio_group;
-extern const struct attribute_group omnia_mcu_poweroff_group;
-
 int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
+extern const struct attribute_group omnia_mcu_poweroff_group;
 int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_TRNG
 int omnia_mcu_register_trng(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_trng(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_WATCHDOG
 int omnia_mcu_register_watchdog(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_watchdog(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
 
 #endif /* __TURRIS_OMNIA_MCU_H */