2011-08-31 09:32:26

by Vivek Natarajan

[permalink] [raw]
Subject: [PATCH] ath6kl: Add debugfs entry to modify roaming parameters.

Firmware initiates roaming only after it reaches a rssi of 20.
This lower rssi threshold can be modified through a wmi command
to modify the roaming behavior.

Signed-off-by: Vivek Natarajan <[email protected]>
---
drivers/net/wireless/ath/ath6kl/core.h | 1 +
drivers/net/wireless/ath/ath6kl/debug.c | 47 ++++++++++++++++++++++++++++++
drivers/net/wireless/ath/ath6kl/init.c | 1 +
drivers/net/wireless/ath/ath6kl/wmi.c | 23 +++++++++++++++
drivers/net/wireless/ath/ath6kl/wmi.h | 48 +++++++++++++++++++++++++++++++
5 files changed, 120 insertions(+), 0 deletions(-)

diff --git a/drivers/net/wireless/ath/ath6kl/core.h b/drivers/net/wireless/ath/ath6kl/core.h
index c5537b3..28540fc 100644
--- a/drivers/net/wireless/ath/ath6kl/core.h
+++ b/drivers/net/wireless/ath/ath6kl/core.h
@@ -402,6 +402,7 @@ struct ath6kl {
u16 bss_ch;
u16 listen_intvl_b;
u16 listen_intvl_t;
+ u8 lrssi_roam_threshold;
struct ath6kl_version version;
u32 target_type;
u8 tx_pwr;
diff --git a/drivers/net/wireless/ath/ath6kl/debug.c b/drivers/net/wireless/ath/ath6kl/debug.c
index 2b46287..aac5bf4 100644
--- a/drivers/net/wireless/ath/ath6kl/debug.c
+++ b/drivers/net/wireless/ath/ath6kl/debug.c
@@ -356,6 +356,51 @@ static const struct file_operations fops_credit_dist_stats = {
.llseek = default_llseek,
};

+static ssize_t write_file_lrssi_roam_threshold(struct file *file,
+ const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct ath6kl *ar = file->private_data;
+ unsigned long lrssi_roam_threshold;
+ char buf[32];
+ ssize_t len;
+
+ len = min(count, sizeof(buf) - 1);
+ if (copy_from_user(buf, user_buf, len))
+ return -EFAULT;
+
+ buf[len] = '\0';
+ if (strict_strtoul(buf, 0, &lrssi_roam_threshold))
+ return -EINVAL;
+
+ ar->lrssi_roam_threshold = lrssi_roam_threshold;
+
+ ath6kl_wmi_set_roam_lrssi_cmd(ar->wmi, ar->lrssi_roam_threshold);
+
+ return count;
+}
+
+static ssize_t read_file_lrssi_roam_threshold(struct file *file,
+ char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct ath6kl *ar = file->private_data;
+ char buf[32];
+ unsigned int len;
+
+ len = snprintf(buf, sizeof(buf), "%u\n", ar->lrssi_roam_threshold);
+
+ return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static const struct file_operations fops_lrssi_roam_threshold = {
+ .read = read_file_lrssi_roam_threshold,
+ .write = write_file_lrssi_roam_threshold,
+ .open = ath6kl_debugfs_open,
+ .owner = THIS_MODULE,
+ .llseek = default_llseek,
+};
+
int ath6kl_debug_init(struct ath6kl *ar)
{
ar->debugfs_phy = debugfs_create_dir("ath6kl",
@@ -369,6 +414,8 @@ int ath6kl_debug_init(struct ath6kl *ar)
debugfs_create_file("credit_dist_stats", S_IRUSR, ar->debugfs_phy, ar,
&fops_credit_dist_stats);

+ debugfs_create_file("lrssi_roam_threshold", S_IRUSR | S_IWUSR,
+ ar->debugfs_phy, ar, &fops_lrssi_roam_threshold);
return 0;
}
#endif
diff --git a/drivers/net/wireless/ath/ath6kl/init.c b/drivers/net/wireless/ath/ath6kl/init.c
index ad9716c..99b63b4 100644
--- a/drivers/net/wireless/ath/ath6kl/init.c
+++ b/drivers/net/wireless/ath/ath6kl/init.c
@@ -292,6 +292,7 @@ static void ath6kl_init_control_info(struct ath6kl *ar)
memset(&ar->sc_params, 0, sizeof(ar->sc_params));
ar->sc_params.short_scan_ratio = WMI_SHORTSCANRATIO_DEFAULT;
ar->sc_params.scan_ctrl_flags = DEFAULT_SCAN_CTRL_FLAGS;
+ ar->lrssi_roam_threshold = DEF_LRSSI_ROAM_THRESHOLD;

memset((u8 *)ar->sta_list, 0,
AP_MAX_NUM_STA * sizeof(struct ath6kl_sta));
diff --git a/drivers/net/wireless/ath/ath6kl/wmi.c b/drivers/net/wireless/ath/ath6kl/wmi.c
index d116d0e..d24f21b 100644
--- a/drivers/net/wireless/ath/ath6kl/wmi.c
+++ b/drivers/net/wireless/ath/ath6kl/wmi.c
@@ -470,6 +470,29 @@ static int ath6kl_wmi_ready_event_rx(struct wmi *wmi, u8 *datap, int len)
return 0;
}

+int ath6kl_wmi_set_roam_lrssi_cmd(struct wmi *wmi, u8 lrssi)
+{
+ struct sk_buff *skb;
+ struct roam_ctrl_cmd *cmd;
+
+ skb = ath6kl_wmi_get_new_buf(sizeof(*cmd));
+ if (!skb)
+ return -ENOMEM;
+
+ cmd = (struct roam_ctrl_cmd *) skb->data;
+
+ cmd->info.params.lrssi_scan_period = cpu_to_le16(DEF_LRSSI_SCAN_PERIOD);
+ cmd->info.params.lrssi_scan_threshold = a_cpu_to_sle16(lrssi +
+ DEF_SCAN_FOR_ROAM_INTVL);
+ cmd->info.params.lrssi_roam_threshold = a_cpu_to_sle16(lrssi);
+ cmd->info.params.roam_rssi_floor = DEF_LRSSI_ROAM_FLOOR;
+ cmd->roam_ctrl = WMI_SET_LRSSI_SCAN_PARAMS;
+
+ ath6kl_wmi_cmd_send(wmi, skb, WMI_SET_ROAM_CTRL_CMDID, NO_SYNC_WMIFLAG);
+
+ return 0;
+}
+
static int ath6kl_wmi_connect_event_rx(struct wmi *wmi, u8 *datap, int len)
{
struct wmi_connect_event *ev;
diff --git a/drivers/net/wireless/ath/ath6kl/wmi.h b/drivers/net/wireless/ath/ath6kl/wmi.h
index 8fa5d6e..4df11e9 100644
--- a/drivers/net/wireless/ath/ath6kl/wmi.h
+++ b/drivers/net/wireless/ath/ath6kl/wmi.h
@@ -1265,6 +1265,53 @@ enum wmi_bi_ftype {
PROBEREQ_FTYPE,
};

+/*
+ * Roam control
+ * Mechanism to modify the roaming behavior in the firmware.
+ * The lower rssi at which the station has to roam can be passed with
+ * WMI_SET_LRSSI_SCAN_PARAMS. Subtract 96 from RSSI to get the signal
+ * level in dBm.
+ */
+#define DEF_LRSSI_SCAN_PERIOD 5
+#define DEF_LRSSI_ROAM_THRESHOLD 20
+#define DEF_LRSSI_ROAM_FLOOR 60
+#define DEF_SCAN_FOR_ROAM_INTVL 2
+
+enum wmi_roam_ctrl {
+ WMI_FORCE_ROAM = 1,
+ WMI_SET_ROAM_MODE,
+ WMI_SET_HOST_BIAS,
+ WMI_SET_LRSSI_SCAN_PARAMS,
+};
+
+struct bss_bias {
+ u8 bssid[ETH_ALEN];
+ u8 bias;
+} __packed;
+
+struct bss_bias_info {
+ u8 num_bss;
+ struct bss_bias bss_bias[1];
+} __packed;
+
+struct low_rssi_scan_params {
+ __le16 lrssi_scan_period;
+ a_sle16 lrssi_scan_threshold;
+ a_sle16 lrssi_roam_threshold;
+ u8 roam_rssi_floor;
+ u8 reserved[1];
+} __packed;
+
+struct roam_ctrl_cmd {
+ union {
+ u8 bssid[ETH_ALEN];
+ u8 roam_mode;
+ struct bss_bias_info bss;
+ struct low_rssi_scan_params params;
+ } __packed info;
+ u8 roam_ctrl;
+} __packed;
+
struct wmi_bss_info_hdr {
__le16 ch;

@@ -1998,6 +2045,7 @@ int ath6kl_wmi_set_keepalive_cmd(struct wmi *wmi, u8 keep_alive_intvl);
s32 ath6kl_wmi_get_rate(s8 rate_index);

int ath6kl_wmi_set_ip_cmd(struct wmi *wmi, struct wmi_set_ip_cmd *ip_cmd);
+int ath6kl_wmi_set_roam_lrssi_cmd(struct wmi *wmi, u8 lrssi);

struct bss *ath6kl_wmi_find_ssid_node(struct wmi *wmi, u8 *ssid,
u32 ssid_len, bool is_wpa2,
--
1.7.1



2011-09-02 09:31:52

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH] ath6kl: Add debugfs entry to modify roaming parameters.

On 08/31/2011 12:32 PM, Vivek Natarajan wrote:
> Firmware initiates roaming only after it reaches a rssi of 20.
> This lower rssi threshold can be modified through a wmi command
> to modify the roaming behavior.

Thanks, applied with minor changes:

commit e5090444be811ce45653969363be8fcb4c52d597
Author: Vivek Natarajan <[email protected]>
Date: Wed Aug 31 15:02:19 2011 +0530

ath6kl: Add debugfs entry to modify roaming parameters.

Firmware initiates roaming only after it reaches a rssi of 20.
This lower rssi threshold can be modified through a wmi command
to modify the roaming behavior.

kvalo: rename debugfs functions and move comment about rssi units
next to
ath6kl_wmi_set_roam_lrssi_cmd()

Signed-off-by: Vivek Natarajan <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>

Kalle