[PATCH] ath11k: Allow debugfs to work with 2+ radios installed.

greearb
2020-09-03T17:24:06Z

From: Ben Greear <greearb@candelatech.com>

The code is trying to create an ath11k directory on debugfs
root, but that fails when there is a second radio (and thus
second instance of the driver).

Work around this by finding a free name. This may fall into
the HACK category, I'm not really sure what the original design
is supposed to accomplish.

Signed-off-by: Ben Greear <greearb@candelatech.com>
---

NOTE: A second radio still does not get far enough to fully boot
the NIC and create a phy* device, but at least system doesn't crash
hard now.

drivers/net/wireless/ath/ath11k/core.h | 5 +++--
drivers/net/wireless/ath/ath11k/debug.c | 23 ++++++++++++++++-------
2 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/core.h b/drivers/net/wireless/ath/ath11k/core.h
index bb22b41fefaa..858dfc700d54 100644
--- a/drivers/net/wireless/ath/ath11k/core.h
+++ b/drivers/net/wireless/ath/ath11k/core.h
@@ -707,8 +707,9 @@ struct ath11k_base {
/* Current DFS Regulatory */
enum ath11k_dfs_region dfs_region;
#ifdef CONFIG_ATH11K_DEBUGFS
- struct dentry *debugfs_soc;
- struct dentry *debugfs_ath11k;
+ struct dentry *debugfs_soc; /* child of debugfs_ath11k */
+ char debugfs_ath11k_fname[36];
+ struct dentry *debugfs_ath11k; /* per driver instance */
#endif
struct ath11k_soc_dp_stats soc_stats;

diff --git a/drivers/net/wireless/ath/ath11k/debug.c b/drivers/net/wireless/ath/ath11k/debug.c
index 31978ef9144e..70b4c4837879 100644
--- a/drivers/net/wireless/ath/ath11k/debug.c
+++ b/drivers/net/wireless/ath/ath11k/debug.c
@@ -1011,15 +1011,24 @@ void ath11k_debug_pdev_destroy(struct ath11k_base *ab)

int ath11k_debug_soc_create(struct ath11k_base *ab)
{
- ab->debugfs_ath11k = debugfs_create_dir("ath11k", NULL);
+ /* We need one of these per driver instance, try until we find an un-used name */
+ int i;

- if (IS_ERR_OR_NULL(ab->debugfs_ath11k)) {
- if (IS_ERR(ab->debugfs_ath11k))
- return PTR_ERR(ab->debugfs_ath11k);
- return -ENOMEM;
+ for (i = 0; i<99; i++) {
+ snprintf(ab->debugfs_ath11k_fname, sizeof(ab->debugfs_ath11k_fname), "ath11k-%d", i);
+ ab->debugfs_ath11k = debugfs_create_dir(ab->debugfs_ath11k_fname, NULL);
+
+ if (!IS_ERR_OR_NULL(ab->debugfs_ath11k)) {
+ return 0;
+ }
}

- return 0;
+ /* Couldn't create one */
+ ab->debugfs_ath11k_fname[0] = 0;
+
+ if (IS_ERR(ab->debugfs_ath11k))
+ return PTR_ERR(ab->debugfs_ath11k);
+ return -ENOMEM;
}

void ath11k_debug_soc_destroy(struct ath11k_base *ab)
@@ -1228,7 +1237,7 @@ int ath11k_debug_register(struct ath11k *ar)
}

/* Create a symlink under ieee80211/phy* */
- snprintf(buf, 100, "../../ath11k/%pd2", ar->debug.debugfs_pdev);
+ snprintf(buf, 100, "../../%s/%pd2", ab->debugfs_ath11k_fname, ar->debug.debugfs_pdev);
debugfs_create_symlink("ath11k", ar->hw->wiphy->debugfsdir, buf);

ath11k_debug_htt_stats_init(ar);
--
2.26.2