cfg80211: Add multiple scan plans for scheduled scan

Add the option to configure multiple 'scan plans' for scheduled scan.
Each 'scan plan' defines the number of scan cycles and the interval
between scans. The scan plans are executed in the order they were
configured. The last scan plan will always run infinitely and thus
defines only the interval between scans.
The maximum number of scan plans supported by the device and the
maximum number of iterations in a single scan plan are advertised
to userspace so it can configure the scan plans appropriately.

When scheduled scan results are received there is no way to know which
scan plan is being currently executed, so there is no way to know when
the next scan iteration will start. This is not a problem, however.
The scan start timestamp is only used for flushing old scan results,
and there is no difference between flushing all results received until
the end of the previous iteration or the start of the current one,
since no results will be received in between.

Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

2 files changed, 81 insertions, 3 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 7f1e9ee844e2..48155be5db7f 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5,6 +5,7 @@
  *
  * Copyright 2006-2010	Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2013-2014 Intel Mobile Communications GmbH
+ * Copyright 2015	Intel Deutschland GmbH
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -1501,13 +1502,26 @@ struct cfg80211_match_set {
 };
 
 /**
+ * struct cfg80211_sched_scan_plan - scan plan for scheduled scan
+ *
+ * @interval: interval between scheduled scan iterations. In seconds.
+ * @iterations: number of scan iterations in this scan plan. Zero means
+ *	infinite loop.
+ *	The last scan plan will always have this parameter set to zero,
+ *	all other scan plans will have a finite number of iterations.
+ */
+struct cfg80211_sched_scan_plan {
+	u32 interval;
+	u32 iterations;
+};
+
+/**
  * struct cfg80211_sched_scan_request - scheduled scan request description
  *
  * @ssids: SSIDs to scan for (passed in the probe_reqs in active scans)
  * @n_ssids: number of SSIDs
  * @n_channels: total number of channels to scan
  * @scan_width: channel width for scanning
- * @interval: interval between each scheduled scan cycle
  * @ie: optional information element(s) to add into Probe Request or %NULL
  * @ie_len: length of ie in octets
  * @flags: bit field of flags controlling operation
@@ -1526,6 +1540,9 @@ struct cfg80211_match_set {
  * @mac_addr_mask: MAC address mask used with randomisation, bits that
  *	are 0 in the mask should be randomised, bits that are 1 should
  *	be taken from the @mac_addr
+ * @scan_plans: scan plans to be executed in this scheduled scan. Lowest
+ *	index must be executed first.
+ * @n_scan_plans: number of scan plans, at least 1.
  * @rcu_head: RCU callback used to free the struct
  * @owner_nlportid: netlink portid of owner (if this should is a request
  *	owned by a particular socket)
@@ -1539,7 +1556,6 @@ struct cfg80211_sched_scan_request {
 	int n_ssids;
 	u32 n_channels;
 	enum nl80211_bss_scan_width scan_width;
-	u32 interval;
 	const u8 *ie;
 	size_t ie_len;
 	u32 flags;
@@ -1547,6 +1563,8 @@ struct cfg80211_sched_scan_request {
 	int n_match_sets;
 	s32 min_rssi_thold;
 	u32 delay;
+	struct cfg80211_sched_scan_plan *scan_plans;
+	int n_scan_plans;
 
 	u8 mac_addr[ETH_ALEN] __aligned(2);
 	u8 mac_addr_mask[ETH_ALEN] __aligned(2);
@@ -3076,6 +3094,12 @@ struct wiphy_vendor_command {
  *	include fixed IEs like supported rates
  * @max_sched_scan_ie_len: same as max_scan_ie_len, but for scheduled
  *	scans
+ * @max_sched_scan_plans: maximum number of scan plans (scan interval and number
+ *	of iterations) for scheduled scan supported by the device.
+ * @max_sched_scan_plan_interval: maximum interval (in seconds) for a
+ *	single scan plan supported by the device.
+ * @max_sched_scan_plan_iterations: maximum number of iterations for a single
+ *	scan plan supported by the device.
  * @coverage_class: current coverage class
  * @fw_version: firmware version for ethtool reporting
  * @hw_version: hardware version for ethtool reporting
@@ -3183,6 +3207,9 @@ struct wiphy {
 	u8 max_match_sets;
 	u16 max_scan_ie_len;
 	u16 max_sched_scan_ie_len;
+	u32 max_sched_scan_plans;
+	u32 max_sched_scan_plan_interval;
+	u32 max_sched_scan_plan_iterations;
 
 	int n_cipher_suites;
 	const u32 *cipher_suites;
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 5dadb844fe18..1f0b4cf5dd03 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -10,6 +10,7 @@
  * Copyright 2008, 2009 Luis R. Rodriguez <lrodriguez@atheros.com>
  * Copyright 2008 Jouni Malinen <jouni.malinen@atheros.com>
  * Copyright 2008 Colin McCabe <colin@cozybit.com>
+ * Copyright 2015	Intel Deutschland GmbH
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -328,7 +329,15 @@
  *	partial scan results may be available
  *
  * @NL80211_CMD_START_SCHED_SCAN: start a scheduled scan at certain
- *	intervals, as specified by %NL80211_ATTR_SCHED_SCAN_INTERVAL.
+ *	intervals and certain number of cycles, as specified by
+ *	%NL80211_ATTR_SCHED_SCAN_PLANS. If %NL80211_ATTR_SCHED_SCAN_PLANS is
+ *	not specified and only %NL80211_ATTR_SCHED_SCAN_INTERVAL is specified,
+ *	scheduled scan will run in an infinite loop with the specified interval.
+ *	These attributes are mutually exculsive,
+ *	i.e. NL80211_ATTR_SCHED_SCAN_INTERVAL must not be passed if
+ *	NL80211_ATTR_SCHED_SCAN_PLANS is defined.
+ *	If for some reason scheduled scan is aborted by the driver, all scan
+ *	plans are canceled (including scan plans that did not start yet).
  *	Like with normal scans, if SSIDs (%NL80211_ATTR_SCAN_SSIDS)
  *	are passed, they are used in the probe requests.  For
  *	broadcast, a broadcast SSID must be passed (ie. an empty
@@ -1761,6 +1770,19 @@ enum nl80211_commands {
  * @NL80211_ATTR_REG_INDOOR: flag attribute, if set indicates that the device
  *      is operating in an indoor environment.
  *
+ * @NL80211_ATTR_MAX_NUM_SCHED_SCAN_PLANS: maximum number of scan plans for
+ *	scheduled scan supported by the device (u32), a wiphy attribute.
+ * @NL80211_ATTR_MAX_SCAN_PLAN_INTERVAL: maximum interval (in seconds) for
+ *	a scan plan (u32), a wiphy attribute.
+ * @NL80211_ATTR_MAX_SCAN_PLAN_ITERATIONS: maximum number of iterations in
+ *	a scan plan (u32), a wiphy attribute.
+ * @NL80211_ATTR_SCHED_SCAN_PLANS: a list of scan plans for scheduled scan.
+ *	Each scan plan defines the number of scan iterations and the interval
+ *	between scans. The last scan plan will always run infinitely,
+ *	thus it must not specify the number of iterations, only the interval
+ *	between scans. The scan plans are executed sequentially.
+ *	Each scan plan is a nested attribute of &enum nl80211_sched_scan_plan.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2130,6 +2152,11 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_REG_INDOOR,
 
+	NL80211_ATTR_MAX_NUM_SCHED_SCAN_PLANS,
+	NL80211_ATTR_MAX_SCAN_PLAN_INTERVAL,
+	NL80211_ATTR_MAX_SCAN_PLAN_ITERATIONS,
+	NL80211_ATTR_SCHED_SCAN_PLANS,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -4593,4 +4620,28 @@ enum nl80211_tdls_peer_capability {
 	NL80211_TDLS_PEER_WMM = 1<<2,
 };
 
+/**
+ * enum nl80211_sched_scan_plan - scanning plan for scheduled scan
+ * @__NL80211_SCHED_SCAN_PLAN_INVALID: attribute number 0 is reserved
+ * @NL80211_SCHED_SCAN_PLAN_INTERVAL: interval between scan iterations. In
+ *	seconds (u32).
+ * @NL80211_SCHED_SCAN_PLAN_ITERATIONS: number of scan iterations in this
+ *	scan plan (u32). The last scan plan must not specify this attribute
+ *	because it will run infinitely. A value of zero is invalid as it will
+ *	make the scan plan meaningless.
+ * @NL80211_SCHED_SCAN_PLAN_MAX: highest scheduled scan plan attribute number
+ *	currently defined
+ * @__NL80211_SCHED_SCAN_PLAN_AFTER_LAST: internal use
+ */
+enum nl80211_sched_scan_plan {
+	__NL80211_SCHED_SCAN_PLAN_INVALID,
+	NL80211_SCHED_SCAN_PLAN_INTERVAL,
+	NL80211_SCHED_SCAN_PLAN_ITERATIONS,
+
+	/* keep last */
+	__NL80211_SCHED_SCAN_PLAN_AFTER_LAST,
+	NL80211_SCHED_SCAN_PLAN_MAX =
+		__NL80211_SCHED_SCAN_PLAN_AFTER_LAST - 1
+};
+
 #endif /* __LINUX_NL80211_H */