mfd: rz-mtu3: Link time dependencies

The new set of drivers for RZ/G2L MTU3a tries to enable compile-testing the
individual client drivers even when the MFD portion is disabled but gets it
wrong, causing a link failure when the core is in a loadable module but the
other drivers are built-in:

x86_64-linux-ld: drivers/pwm/pwm-rz-mtu3.o: in function `rz_mtu3_pwm_apply':
pwm-rz-mtu3.c:(.text+0x4bf): undefined reference to `rz_mtu3_8bit_ch_write'
x86_64-linux-ld: pwm-rz-mtu3.c:(.text+0x509): undefined reference to `rz_mtu3_disable'

arm-linux-gnueabi-ld: drivers/counter/rz-mtu3-cnt.o: in function `rz_mtu3_cascade_counts_enable_get':
rz-mtu3-cnt.c:(.text+0xbec): undefined reference to `rz_mtu3_shared_reg_read'

It seems better not to add the extra complexity here but instead just use
a normal hard dependency, so remove the #else portion in the header along
with the "|| COMPILE_TEST". This could also be fixed by having slightly more
elaborate Kconfig dependencies or using the cursed 'IS_REACHABLE()' helper,
but in practice it's already possible to compile-test all these drivers
by enabling the mtd portion.

Fixes: 254d3a72 ("pwm: Add Renesas RZ/G2L MTU3a PWM driver")
Fixes: 0be89073 ("counter: Add Renesas RZ/G2L MTU3a counter driver")
Fixes: 654c293e ("mfd: Add Renesas RZ/G2L MTU3a core driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230719090430.1925182-1-arnd@kernel.orgSigned-off-by: Lee Jones <lee@kernel.org>

drivers/counter/Kconfig

@@ -92,7 +92,7 @@ config MICROCHIP_TCB_CAPTURE
 
 config RZ_MTU3_CNT
 	tristate "Renesas RZ/G2L MTU3a counter driver"
-	depends on RZ_MTU3 || COMPILE_TEST
+	depends on RZ_MTU3
 	help
 	  Enable support for MTU3a counter driver found on Renesas RZ/G2L alike
 	  SoCs. This IP supports both 16-bit and 32-bit phase counting mode

drivers/pwm/Kconfig

@@ -505,7 +505,7 @@ config PWM_ROCKCHIP
 
 config PWM_RZ_MTU3
 	tristate "Renesas RZ/G2L MTU3a PWM Timer support"
-	depends on RZ_MTU3 || COMPILE_TEST
+	depends on RZ_MTU3
 	depends on HAS_IOMEM
 	help
 	  This driver exposes the MTU3a PWM Timer controller found in Renesas

include/linux/mfd/rz-mtu3.h

@@ -151,7 +151,6 @@ struct rz_mtu3 {
 	void *priv_data;
 };
 
-#if IS_ENABLED(CONFIG_RZ_MTU3)
 static inline bool rz_mtu3_request_channel(struct rz_mtu3_channel *ch)
 {
 	mutex_lock(&ch->lock);
@@ -188,70 +187,5 @@ void rz_mtu3_32bit_ch_write(struct rz_mtu3_channel *ch, u16 off, u32 val);
 void rz_mtu3_shared_reg_write(struct rz_mtu3_channel *ch, u16 off, u16 val);
 void rz_mtu3_shared_reg_update_bit(struct rz_mtu3_channel *ch, u16 off,
 				   u16 pos, u8 val);
-#else
-static inline bool rz_mtu3_request_channel(struct rz_mtu3_channel *ch)
-{
-	return false;
-}
-
-static inline void rz_mtu3_release_channel(struct rz_mtu3_channel *ch)
-{
-}
-
-static inline bool rz_mtu3_is_enabled(struct rz_mtu3_channel *ch)
-{
-	return false;
-}
-
-static inline void rz_mtu3_disable(struct rz_mtu3_channel *ch)
-{
-}
-
-static inline int rz_mtu3_enable(struct rz_mtu3_channel *ch)
-{
-	return 0;
-}
-
-static inline u8 rz_mtu3_8bit_ch_read(struct rz_mtu3_channel *ch, u16 off)
-{
-	return 0;
-}
-
-static inline u16 rz_mtu3_16bit_ch_read(struct rz_mtu3_channel *ch, u16 off)
-{
-	return 0;
-}
-
-static inline u32 rz_mtu3_32bit_ch_read(struct rz_mtu3_channel *ch, u16 off)
-{
-	return 0;
-}
-
-static inline u16 rz_mtu3_shared_reg_read(struct rz_mtu3_channel *ch, u16 off)
-{
-	return 0;
-}
-
-static inline void rz_mtu3_8bit_ch_write(struct rz_mtu3_channel *ch, u16 off, u8 val)
-{
-}
-
-static inline void rz_mtu3_16bit_ch_write(struct rz_mtu3_channel *ch, u16 off, u16 val)
-{
-}
-
-static inline void rz_mtu3_32bit_ch_write(struct rz_mtu3_channel *ch, u16 off, u32 val)
-{
-}
-
-static inline void rz_mtu3_shared_reg_write(struct rz_mtu3_channel *ch, u16 off, u16 val)
-{
-}
-
-static inline void rz_mtu3_shared_reg_update_bit(struct rz_mtu3_channel *ch,
-						 u16 off, u16 pos, u8 val)
-{
-}
-#endif
 
 #endif /* __MFD_RZ_MTU3_H__ */