[PATCH RESEND net-next 4/5] net: wwan: iosm: make debugfs optional

[Sergey Ryazanov <ryazanov.s.a@gmail.com>]

Collecting modem firmware traces is optional for the regular modem use.
Some distros and users will want to disable this feature for security or
kernel size reasons. So add a configuration option that allows to
completely disable the driver debugfs interface.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
---
 drivers/net/wwan/Kconfig                 |  8 ++++++++
 drivers/net/wwan/iosm/Makefile           |  4 +++-
 drivers/net/wwan/iosm/iosm_ipc_debugfs.h |  5 +++++
 drivers/net/wwan/iosm/iosm_ipc_imem.c    |  2 +-
 drivers/net/wwan/iosm/iosm_ipc_imem.h    |  4 ++++
 drivers/net/wwan/iosm/iosm_ipc_trace.c   |  6 ++++--
 drivers/net/wwan/iosm/iosm_ipc_trace.h   | 20 +++++++++++++++++++-
 7 files changed, 44 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wwan/Kconfig b/drivers/net/wwan/Kconfig
index 17543be14665..e204e74edcec 100644
--- a/drivers/net/wwan/Kconfig
+++ b/drivers/net/wwan/Kconfig
@@ -80,6 +80,14 @@ config IOSM
 
 	  If unsure, say N.
 
+config IOSM_DEBUGFS
+	bool "IOSM Debugfs support"
+	depends on IOSM && DEBUG_FS
+	help
+	  Enables debugfs driver interface for traces collection.
+
+	  If unsure, say N.
+
 endif # WWAN
 
 endmenu
diff --git a/drivers/net/wwan/iosm/Makefile b/drivers/net/wwan/iosm/Makefile
index 5091f664af0d..bf28b29f6151 100644
--- a/drivers/net/wwan/iosm/Makefile
+++ b/drivers/net/wwan/iosm/Makefile
@@ -21,7 +21,9 @@ iosm-y = \
 	iosm_ipc_mux_codec.o		\
 	iosm_ipc_devlink.o		\
 	iosm_ipc_flash.o		\
-	iosm_ipc_coredump.o		\
+	iosm_ipc_coredump.o
+
+iosm-$(CONFIG_IOSM_DEBUGFS) += \
 	iosm_ipc_debugfs.o		\
 	iosm_ipc_trace.o
 
diff --git a/drivers/net/wwan/iosm/iosm_ipc_debugfs.h b/drivers/net/wwan/iosm/iosm_ipc_debugfs.h
index 35788039f13f..3e3bb968fa03 100644
--- a/drivers/net/wwan/iosm/iosm_ipc_debugfs.h
+++ b/drivers/net/wwan/iosm/iosm_ipc_debugfs.h
@@ -6,7 +6,12 @@
 #ifndef IOSM_IPC_DEBUGFS_H
 #define IOSM_IPC_DEBUGFS_H
 
+#ifdef CONFIG_IOSM_DEBUGFS
 void ipc_debugfs_init(struct iosm_imem *ipc_imem);
 void ipc_debugfs_deinit(struct iosm_imem *ipc_imem);
+#else
+static inline void ipc_debugfs_init(struct iosm_imem *ipc_imem) {}
+static inline void ipc_debugfs_deinit(struct iosm_imem *ipc_imem) {}
+#endif
 
 #endif
diff --git a/drivers/net/wwan/iosm/iosm_ipc_imem.c b/drivers/net/wwan/iosm/iosm_ipc_imem.c
index 25b889922912..2a6ddd7c6c88 100644
--- a/drivers/net/wwan/iosm/iosm_ipc_imem.c
+++ b/drivers/net/wwan/iosm/iosm_ipc_imem.c
@@ -274,7 +274,7 @@ static void ipc_imem_dl_skb_process(struct iosm_imem *ipc_imem,
 			ipc_imem_sys_devlink_notify_rx(ipc_imem->ipc_devlink,
 						       skb);
 		else if (ipc_is_trace_channel(ipc_imem, port_id))
-			ipc_trace_port_rx(ipc_imem->trace, skb);
+			ipc_trace_port_rx(ipc_imem, skb);
 		else
 			wwan_port_rx(ipc_imem->ipc_port[port_id]->iosm_port,
 				     skb);
diff --git a/drivers/net/wwan/iosm/iosm_ipc_imem.h b/drivers/net/wwan/iosm/iosm_ipc_imem.h
index df3b471f6fa9..cca4b32c63cd 100644
--- a/drivers/net/wwan/iosm/iosm_ipc_imem.h
+++ b/drivers/net/wwan/iosm/iosm_ipc_imem.h
@@ -350,7 +350,9 @@ struct iosm_imem {
 	struct iosm_mux *mux;
 	struct iosm_cdev *ipc_port[IPC_MEM_MAX_CHANNELS];
 	struct iosm_pcie *pcie;
+#ifdef CONFIG_IOSM_DEBUGFS
 	struct iosm_trace *trace;
+#endif
 	struct device *dev;
 	enum ipc_mem_device_ipc_state ipc_requested_state;
 	struct ipc_mem_channel channels[IPC_MEM_MAX_CHANNELS];
@@ -380,7 +382,9 @@ struct iosm_imem {
 	   ev_mux_net_transmit_pending:1,
 	   reset_det_n:1,
 	   pcie_wake_n:1;
+#ifdef CONFIG_IOSM_DEBUGFS
 	struct dentry *debugfs_dir;
+#endif
 };
 
 /**
diff --git a/drivers/net/wwan/iosm/iosm_ipc_trace.c b/drivers/net/wwan/iosm/iosm_ipc_trace.c
index 5243ead90b5f..eeecfa3d10c5 100644
--- a/drivers/net/wwan/iosm/iosm_ipc_trace.c
+++ b/drivers/net/wwan/iosm/iosm_ipc_trace.c
@@ -17,11 +17,13 @@
 
 /**
  * ipc_trace_port_rx - Receive trace packet from cp and write to relay buffer
- * @ipc_trace:  Pointer to the ipc trace data-struct
+ * @ipc_imem:   Pointer to iosm_imem structure
  * @skb:        Pointer to struct sk_buff
  */
-void ipc_trace_port_rx(struct iosm_trace *ipc_trace, struct sk_buff *skb)
+void ipc_trace_port_rx(struct iosm_imem *ipc_imem, struct sk_buff *skb)
 {
+	struct iosm_trace *ipc_trace = ipc_imem->trace;
+
 	if (ipc_trace->ipc_rchan)
 		relay_write(ipc_trace->ipc_rchan, skb->data, skb->len);
 
diff --git a/drivers/net/wwan/iosm/iosm_ipc_trace.h b/drivers/net/wwan/iosm/iosm_ipc_trace.h
index 419540c91219..0d74836df90c 100644
--- a/drivers/net/wwan/iosm/iosm_ipc_trace.h
+++ b/drivers/net/wwan/iosm/iosm_ipc_trace.h
@@ -45,6 +45,8 @@ struct iosm_trace {
 	enum trace_ctrl_mode mode;
 };
 
+#ifdef CONFIG_IOSM_DEBUGFS
+
 static inline bool ipc_is_trace_channel(struct iosm_imem *ipc_mem, u16 chl_id)
 {
 	return ipc_mem->trace && ipc_mem->trace->chl_id == chl_id;
@@ -52,5 +54,21 @@ static inline bool ipc_is_trace_channel(struct iosm_imem *ipc_mem, u16 chl_id)
 
 struct iosm_trace *ipc_trace_init(struct iosm_imem *ipc_imem);
 void ipc_trace_deinit(struct iosm_trace *ipc_trace);
-void ipc_trace_port_rx(struct iosm_trace *ipc_trace, struct sk_buff *skb);
+void ipc_trace_port_rx(struct iosm_imem *ipc_imem, struct sk_buff *skb);
+
+#else
+
+static inline bool ipc_is_trace_channel(struct iosm_imem *ipc_mem, u16 chl_id)
+{
+	return false;
+}
+
+static inline void ipc_trace_port_rx(struct iosm_imem *ipc_imem,
+				     struct sk_buff *skb)
+{
+	dev_kfree_skb(skb);
+}
+
+#endif
+
 #endif
-- 
2.32.0