[RFC 4/6] drm/bridge/sii8620: fix extcon dependency

[Arnd Bergmann]

Using 'imply' does not work here, it still cause the same build
failure:

arm-linux-gnueabi-ld: drivers/gpu/drm/bridge/sil-sii8620.o: in function `sii8620_remove':
sil-sii8620.c:(.text+0x1b8): undefined reference to `extcon_unregister_notifier'
arm-linux-gnueabi-ld: drivers/gpu/drm/bridge/sil-sii8620.o: in function `sii8620_probe':
sil-sii8620.c:(.text+0x27e8): undefined reference to `extcon_find_edev_by_node'
arm-linux-gnueabi-ld: sil-sii8620.c:(.text+0x2870): undefined reference to `extcon_register_notifier'
arm-linux-gnueabi-ld: drivers/gpu/drm/bridge/sil-sii8620.o: in function `sii8620_extcon_work':
sil-sii8620.c:(.text+0x2908): undefined reference to `extcon_get_state'

I tried the usual 'depends on EXTCON || !EXTCON' logic, but that caused
a circular Kconfig dependency. Using IS_REACHABLE() is ugly but works.

Fixes: 7a109673899b ("drm/bridge/sii8620: add Kconfig dependency on extcon")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 drivers/gpu/drm/bridge/Kconfig       | 1 -
 drivers/gpu/drm/bridge/sil-sii8620.c | 5 +++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index aaed2347ace9..78e5ba06acff 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -90,7 +90,6 @@ config DRM_SIL_SII8620
 	tristate "Silicon Image SII8620 HDMI/MHL bridge"
 	depends on OF
 	select DRM_KMS_HELPER
-	imply EXTCON
 	depends on RC_CORE || !RC_CORE
 	help
 	  Silicon Image SII8620 HDMI/MHL bridge chip driver.
diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
index 92acd336aa89..94b6c38e6855 100644
--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -2330,7 +2330,8 @@ static int sii8620_probe(struct i2c_client *client,
 	if (ret)
 		return ret;
 
-	ret = sii8620_extcon_init(ctx);
+	if (IS_REACHABLE(CONFIG_EXTCON))
+		ret = sii8620_extcon_init(ctx);
 	if (ret < 0) {
 		dev_err(ctx->dev, "failed to initialize EXTCON\n");
 		return ret;
@@ -2352,7 +2353,7 @@ static int sii8620_remove(struct i2c_client *client)
 {
 	struct sii8620 *ctx = i2c_get_clientdata(client);
 
-	if (ctx->extcon) {
+	if (IS_REACHABLE(CONFIG_EXTCON) && ctx->extcon) {
 		extcon_unregister_notifier(ctx->extcon, EXTCON_DISP_MHL,
 					   &ctx->extcon_nb);
 		flush_work(&ctx->extcon_wq);
-- 
2.26.0