10 files changed, 488 insertions, 25 deletions

diff --git a/Documentation/ABI/testing/sysfs-class-net-mesh b/Documentation/ABI/testing/sysfs-class-net-mesh
index b218e0f8bdb3..c81fe89c4c46 100644
--- a/Documentation/ABI/testing/sysfs-class-net-mesh
+++ b/Documentation/ABI/testing/sysfs-class-net-mesh
@@ -14,6 +14,15 @@ Description:
                 mesh will be sent using multiple interfaces at the
                 same time (if available).
 
+What:           /sys/class/net/<mesh_iface>/mesh/bridge_loop_avoidance
+Date:           November 2011
+Contact:        Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
+Description:
+                Indicates whether the bridge loop avoidance feature
+                is enabled. This feature detects and avoids loops
+                between the mesh and devices bridged with the soft
+                interface <mesh_iface>.
+
 What:           /sys/class/net/<mesh_iface>/mesh/fragmentation
 Date:           October 2010
 Contact:        Andreas Langer <an.langer@gmx.de>
diff --git a/Documentation/DocBook/80211.tmpl b/Documentation/DocBook/80211.tmpl
index c5ac6929c41c..f3e214f9e256 100644
--- a/Documentation/DocBook/80211.tmpl
+++ b/Documentation/DocBook/80211.tmpl
@@ -516,7 +516,7 @@
 !Finclude/net/mac80211.h ieee80211_start_tx_ba_cb_irqsafe
 !Finclude/net/mac80211.h ieee80211_stop_tx_ba_session
 !Finclude/net/mac80211.h ieee80211_stop_tx_ba_cb_irqsafe
-!Finclude/net/mac80211.h rate_control_changed
+!Finclude/net/mac80211.h ieee80211_rate_control_changed
 !Finclude/net/mac80211.h ieee80211_tx_rate_control
 !Finclude/net/mac80211.h rate_control_send_low
       </chapter>
diff --git a/Documentation/devicetree/bindings/net/mdio-mux-gpio.txt b/Documentation/devicetree/bindings/net/mdio-mux-gpio.txt
new file mode 100644
index 000000000000..79384113c2b0
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/mdio-mux-gpio.txt
@@ -0,0 +1,127 @@
+Properties for an MDIO bus multiplexer/switch controlled by GPIO pins.
+
+This is a special case of a MDIO bus multiplexer.  One or more GPIO
+lines are used to control which child bus is connected.
+
+Required properties in addition to the generic multiplexer properties:
+
+- compatible : mdio-mux-gpio.
+- gpios : GPIO specifiers for each GPIO line.  One or more must be specified.
+
+
+Example :
+
+        /* The parent MDIO bus. */
+        smi1: mdio@1180000001900 {
+                compatible = "cavium,octeon-3860-mdio";
+                #address-cells = <1>;
+                #size-cells = <0>;
+                reg = <0x11800 0x00001900 0x0 0x40>;
+        };
+
+        /*
+           An NXP sn74cbtlv3253 dual 1-of-4 switch controlled by a
+           pair of GPIO lines.  Child busses 2 and 3 populated with 4
+           PHYs each.
+         */
+        mdio-mux {
+                compatible = "mdio-mux-gpio";
+                gpios = <&gpio1 3 0>, <&gpio1 4 0>;
+                mdio-parent-bus = <&smi1>;
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                mdio@2 {
+                        reg = <2>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+
+                        phy11: ethernet-phy@1 {
+                                reg = <1>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                        phy12: ethernet-phy@2 {
+                                reg = <2>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                        phy13: ethernet-phy@3 {
+                                reg = <3>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                        phy14: ethernet-phy@4 {
+                                reg = <4>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                };
+
+                mdio@3 {
+                        reg = <3>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+
+                        phy21: ethernet-phy@1 {
+                                reg = <1>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                        phy22: ethernet-phy@2 {
+                                reg = <2>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                        phy23: ethernet-phy@3 {
+                                reg = <3>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                        phy24: ethernet-phy@4 {
+                                reg = <4>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                };
+        };
diff --git a/Documentation/devicetree/bindings/net/mdio-mux.txt b/Documentation/devicetree/bindings/net/mdio-mux.txt
new file mode 100644
index 000000000000..f65606f8d632
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/mdio-mux.txt
@@ -0,0 +1,136 @@
+Common MDIO bus multiplexer/switch properties.
+
+An MDIO bus multiplexer/switch will have several child busses that are
+numbered uniquely in a device dependent manner.  The nodes for an MDIO
+bus multiplexer/switch will have one child node for each child bus.
+
+Required properties:
+- mdio-parent-bus : phandle to the parent MDIO bus.
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Optional properties:
+- Other properties specific to the multiplexer/switch hardware.
+
+Required properties for child nodes:
+- #address-cells = <1>;
+- #size-cells = <0>;
+- reg : The sub-bus number.
+
+
+Example :
+
+        /* The parent MDIO bus. */
+        smi1: mdio@1180000001900 {
+                compatible = "cavium,octeon-3860-mdio";
+                #address-cells = <1>;
+                #size-cells = <0>;
+                reg = <0x11800 0x00001900 0x0 0x40>;
+        };
+
+        /*
+           An NXP sn74cbtlv3253 dual 1-of-4 switch controlled by a
+           pair of GPIO lines.  Child busses 2 and 3 populated with 4
+           PHYs each.
+         */
+        mdio-mux {
+                compatible = "mdio-mux-gpio";
+                gpios = <&gpio1 3 0>, <&gpio1 4 0>;
+                mdio-parent-bus = <&smi1>;
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                mdio@2 {
+                        reg = <2>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+
+                        phy11: ethernet-phy@1 {
+                                reg = <1>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                        phy12: ethernet-phy@2 {
+                                reg = <2>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                        phy13: ethernet-phy@3 {
+                                reg = <3>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                        phy14: ethernet-phy@4 {
+                                reg = <4>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <10 8>; /* Pin 10, active low */
+                        };
+                };
+
+                mdio@3 {
+                        reg = <3>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+
+                        phy21: ethernet-phy@1 {
+                                reg = <1>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                        phy22: ethernet-phy@2 {
+                                reg = <2>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                        phy23: ethernet-phy@3 {
+                                reg = <3>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                        phy24: ethernet-phy@4 {
+                                reg = <4>;
+                                compatible = "marvell,88e1149r";
+                                marvell,reg-init = <3 0x10 0 0x5777>,
+                                        <3 0x11 0 0x00aa>,
+                                        <3 0x12 0 0x4105>,
+                                        <3 0x13 0 0x0a60>;
+                                interrupt-parent = <&gpio>;
+                                interrupts = <12 8>; /* Pin 12, active low */
+                        };
+                };
+        };
diff --git a/Documentation/networking/batman-adv.txt b/Documentation/networking/batman-adv.txt
index 221ad0cdf11f..220a58c2fb11 100644
--- a/Documentation/networking/batman-adv.txt
+++ b/Documentation/networking/batman-adv.txt
@@ -67,18 +67,18 @@ To deactivate an interface you have  to  write  "none"  into  its
 All  mesh  wide  settings  can be found in batman's own interface
 folder:
 
-#  ls  /sys/class/net/bat0/mesh/
-# aggregated_ogms   fragmentation gw_sel_class   vis_mode
-# ap_isolation      gw_bandwidth  hop_penalty
-# bonding           gw_mode       orig_interval
+# ls /sys/class/net/bat0/mesh/
+# aggregated_ogms        fragmentation          hop_penalty
+# ap_isolation           gw_bandwidth           log_level
+# bonding                gw_mode                orig_interval
+# bridge_loop_avoidance  gw_sel_class           vis_mode
 
 
 There is a special folder for debugging information:
 
 #  ls /sys/kernel/debug/batman_adv/bat0/
-#  gateways     socket        transtable_global  vis_data
-#  originators  softif_neigh  transtable_local
-
+# bla_claim_table    log                socket             transtable_local
+# gateways           originators        transtable_global  vis_data
 
 Some of the files contain all sort of status information  regard-
 ing  the  mesh  network.  For  example, you can view the table of
@@ -202,12 +202,13 @@ abled  during run time. Following log_levels are defined:
 1 - Enable messages related to routing / flooding / broadcasting
 2 - Enable messages related to route added / changed / deleted
 4 - Enable messages related to translation table operations
-7 - Enable all messages
+8 - Enable messages related to bridge loop avoidance
+15 - enable all messages
 
 The debug output can be changed at runtime  using  the  file
 /sys/class/net/bat0/mesh/log_level. e.g.
 
-# echo 2 > /sys/class/net/bat0/mesh/log_level
+# echo 6 > /sys/class/net/bat0/mesh/log_level
 
 will enable debug messages for when routes change.
 
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 1619a8c80873..90b0c4fd275b 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -190,6 +190,20 @@ tcp_cookie_size - INTEGER
 tcp_dsack - BOOLEAN
         Allows TCP to send "duplicate" SACKs.
 
+tcp_early_retrans - INTEGER
+        Enable Early Retransmit (ER), per RFC 5827. ER lowers the threshold
+        for triggering fast retransmit when the amount of outstanding data is
+        small and when no previously unsent data can be transmitted (such
+        that limited transmit could be used).
+        Possible values:
+                0 disables ER
+                1 enables ER
+                2 enables ER but delays fast recovery and fast retransmit
+                  by a fourth of RTT. This mitigates connection falsely
+                  recovers when network has a small degree of reordering
+                  (less than 3 packets).
+        Default: 2
+
 tcp_ecn - INTEGER
         Enable Explicit Congestion Notification (ECN) in TCP. ECN is only
         used when both ends of the TCP flow support it. It is useful to
@@ -1484,11 +1498,8 @@ addr_scope_policy - INTEGER
 
 
 /proc/sys/net/core/*
-dev_weight - INTEGER
-        The maximum number of packets that kernel can handle on a NAPI
-        interrupt, it's a Per-CPU variable.
+        Please see: Documentation/sysctl/net.txt for descriptions of these entries.
 
-        Default: 64
 
 /proc/sys/net/unix/*
 max_dgram_qlen - INTEGER
diff --git a/Documentation/networking/mac80211-auth-assoc-deauth.txt b/Documentation/networking/mac80211-auth-assoc-deauth.txt
index e0a2aa585ca3..d7a15fe91bf7 100644
--- a/Documentation/networking/mac80211-auth-assoc-deauth.txt
+++ b/Documentation/networking/mac80211-auth-assoc-deauth.txt
@@ -23,7 +23,7 @@ BA session stop & deauth/disassoc frames
 end note
 end
 
-mac80211->driver: config(channel, non-HT)
+mac80211->driver: config(channel, channel type)
 mac80211->driver: bss_info_changed(set BSSID, basic rate bitmap)
 mac80211->driver: sta_state(AP, exists)
 
@@ -51,7 +51,7 @@ note over mac80211,driver: cleanup like for authenticate
 end
 
 alt not previously authenticated (FT)
-mac80211->driver: config(channel, non-HT)
+mac80211->driver: config(channel, channel type)
 mac80211->driver: bss_info_changed(set BSSID, basic rate bitmap)
 mac80211->driver: sta_state(AP, exists)
 mac80211->driver: sta_state(AP, authenticated)
@@ -67,10 +67,6 @@ end
 
 mac80211->driver: set up QoS parameters
 
-alt is HT channel
-mac80211->driver: config(channel, HT params)
-end
-
 mac80211->driver: bss_info_changed(QoS, HT, associated with AID)
 mac80211->userspace: associated
 
@@ -95,5 +91,5 @@ mac80211->driver: sta_state(AP,exists)
 mac80211->driver: sta_state(AP,not-exists)
 mac80211->driver: turn off powersave
 mac80211->driver: bss_info_changed(clear BSSID, not associated, no QoS, ...)
-mac80211->driver: config(non-HT channel type)
+mac80211->driver: config(channel type to non-HT)
 mac80211->userspace: disconnected
diff --git a/Documentation/networking/stmmac.txt b/Documentation/networking/stmmac.txt
index d0aeeadd264b..ab1e8d7004c5 100644
--- a/Documentation/networking/stmmac.txt
+++ b/Documentation/networking/stmmac.txt
@@ -111,11 +111,12 @@ and detailed below as well:
         int phy_addr;
         int interface;
         struct stmmac_mdio_bus_data *mdio_bus_data;
-        int pbl;
+        struct stmmac_dma_cfg *dma_cfg;
         int clk_csr;
         int has_gmac;
         int enh_desc;
         int tx_coe;
+        int rx_coe;
         int bugged_jumbo;
         int pmt;
         int force_sf_dma_mode;
@@ -136,10 +137,12 @@ Where:
  o pbl: the Programmable Burst Length is maximum number of beats to
        be transferred in one DMA transaction.
        GMAC also enables the 4xPBL by default.
- o clk_csr: CSR Clock range selection.
+ o clk_csr: fixed CSR Clock range selection.
  o has_gmac: uses the GMAC core.
  o enh_desc: if sets the MAC will use the enhanced descriptor structure.
  o tx_coe: core is able to perform the tx csum in HW.
+ o rx_coe: the supports three check sum offloading engine types:
+           type_1, type_2 (full csum) and no RX coe.
  o bugged_jumbo: some HWs are not able to perform the csum in HW for
                 over-sized frames due to limited buffer sizes.
                 Setting this flag the csum will be done in SW on
@@ -160,7 +163,7 @@ Where:
  o custom_cfg: this is a custom configuration that can be passed while
               initialising the resources.
 
-The we have:
+For MDIO bus The we have:
 
  struct stmmac_mdio_bus_data {
         int bus_id;
@@ -177,10 +180,28 @@ Where:
  o irqs: list of IRQs, one per PHY.
  o probed_phy_irq: if irqs is NULL, use this for probed PHY.
 
+
+For DMA engine we have the following internal fields that should be
+tuned according to the HW capabilities.
+
+struct stmmac_dma_cfg {
+        int pbl;
+        int fixed_burst;
+        int burst_len_supported;
+};
+
+Where:
+ o pbl: Programmable Burst Length
+ o fixed_burst: program the DMA to use the fixed burst mode
+ o burst_len: this is the value we put in the register
+              supported values are provided as macros in
+              linux/stmmac.h header file.
+
+---
+
 Below an example how the structures above are using on ST platforms.
 
  static struct plat_stmmacenet_data stxYYY_ethernet_platform_data = {
-        .pbl = 32,
         .has_gmac = 0,
         .enh_desc = 0,
         .fix_mac_speed = stxYYY_ethernet_fix_mac_speed,
diff --git a/Documentation/nfc/nfc-hci.txt b/Documentation/nfc/nfc-hci.txt
new file mode 100644
index 000000000000..216b7254fcc3
--- /dev/null
+++ b/Documentation/nfc/nfc-hci.txt
@@ -0,0 +1,155 @@
+HCI backend for NFC Core
+
+Author: Eric Lapuyade, Samuel Ortiz
+Contact: eric.lapuyade@intel.com, samuel.ortiz@intel.com
+
+General
+-------
+
+The HCI layer implements much of the ETSI TS 102 622 V10.2.0 specification. It
+enables easy writing of HCI-based NFC drivers. The HCI layer runs as an NFC Core
+backend, implementing an abstract nfc device and translating NFC Core API
+to HCI commands and events.
+
+HCI
+---
+
+HCI registers as an nfc device with NFC Core. Requests coming from userspace are
+routed through netlink sockets to NFC Core and then to HCI. From this point,
+they are translated in a sequence of HCI commands sent to the HCI layer in the
+host controller (the chip). The sending context blocks while waiting for the
+response to arrive.
+HCI events can also be received from the host controller. They will be handled
+and a translation will be forwarded to NFC Core as needed.
+HCI uses 2 execution contexts:
+- one if for executing commands : nfc_hci_msg_tx_work(). Only one command
+can be executing at any given moment.
+- one if for dispatching received events and responses : nfc_hci_msg_rx_work()
+
+HCI Session initialization:
+---------------------------
+
+The Session initialization is an HCI standard which must unfortunately
+support proprietary gates. This is the reason why the driver will pass a list
+of proprietary gates that must be part of the session. HCI will ensure all
+those gates have pipes connected when the hci device is set up.
+
+HCI Gates and Pipes
+-------------------
+
+A gate defines the 'port' where some service can be found. In order to access
+a service, one must create a pipe to that gate and open it. In this
+implementation, pipes are totally hidden. The public API only knows gates.
+This is consistent with the driver need to send commands to proprietary gates
+without knowing the pipe connected to it.
+
+Driver interface
+----------------
+
+A driver would normally register itself with HCI and provide the following
+entry points:
+
+struct nfc_hci_ops {
+        int (*open)(struct nfc_hci_dev *hdev);
+        void (*close)(struct nfc_hci_dev *hdev);
+        int (*xmit)(struct nfc_hci_dev *hdev, struct sk_buff *skb);
+        int (*start_poll)(struct nfc_hci_dev *hdev, u32 protocols);
+        int (*target_from_gate)(struct nfc_hci_dev *hdev, u8 gate,
+                                struct nfc_target *target);
+};
+
+open() and close() shall turn the hardware on and off. xmit() shall simply
+write a frame to the chip. start_poll() is an optional entrypoint that shall
+set the hardware in polling mode. This must be implemented only if the hardware
+uses proprietary gates or a mechanism slightly different from the HCI standard.
+target_from_gate() is another optional entrypoint to return the protocols
+corresponding to a proprietary gate.
+
+On the rx path, the driver is responsible to push incoming HCP frames to HCI
+using nfc_hci_recv_frame(). HCI will take care of re-aggregation and handling
+This must be done from a context that can sleep.
+
+SHDLC
+-----
+
+Most chips use shdlc to ensure integrity and delivery ordering of the HCP
+frames between the host controller (the chip) and hosts (entities connected
+to the chip, like the cpu). In order to simplify writing the driver, an shdlc
+layer is available for use by the driver.
+When used, the driver actually registers with shdlc, and shdlc will register
+with HCI. HCI sees shdlc as the driver and thus send its HCP frames
+through shdlc->xmit.
+SHDLC adds a new execution context (nfc_shdlc_sm_work()) to run its state
+machine and handle both its rx and tx path.
+
+Included Drivers
+----------------
+
+An HCI based driver for an NXP PN544, connected through I2C bus, and using
+shdlc is included.
+
+Execution Contexts
+------------------
+
+The execution contexts are the following:
+- IRQ handler (IRQH):
+fast, cannot sleep. stores incoming frames into an shdlc rx queue
+
+- SHDLC State Machine worker (SMW)
+handles shdlc rx & tx queues. Dispatches HCI cmd responses.
+
+- HCI Tx Cmd worker (MSGTXWQ)
+Serialize execution of HCI commands. Complete execution in case of resp timeout.
+
+- HCI Rx worker (MSGRXWQ)
+Dispatches incoming HCI commands or events.
+
+- Syscall context from a userspace call (SYSCALL)
+Any entrypoint in HCI called from NFC Core
+
+Workflow executing an HCI command (using shdlc)
+-----------------------------------------------
+
+Executing an HCI command can easily be performed synchronously using the
+following API:
+
+int nfc_hci_send_cmd (struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
+                        const u8 *param, size_t param_len, struct sk_buff **skb)
+
+The API must be invoked from a context that can sleep. Most of the time, this
+will be the syscall context. skb will return the result that was received in
+the response.
+
+Internally, execution is asynchronous. So all this API does is to enqueue the
+HCI command, setup a local wait queue on stack, and wait_event() for completion.
+The wait is not interruptible because it is guaranteed that the command will
+complete after some short timeout anyway.
+
+MSGTXWQ context will then be scheduled and invoke nfc_hci_msg_tx_work().
+This function will dequeue the next pending command and send its HCP fragments
+to the lower layer which happens to be shdlc. It will then start a timer to be
+able to complete the command with a timeout error if no response arrive.
+
+SMW context gets scheduled and invokes nfc_shdlc_sm_work(). This function
+handles shdlc framing in and out. It uses the driver xmit to send frames and
+receives incoming frames in an skb queue filled from the driver IRQ handler.
+SHDLC I(nformation) frames payload are HCP fragments. They are agregated to
+form complete HCI frames, which can be a response, command, or event.
+
+HCI Responses are dispatched immediately from this context to unblock
+waiting command execution. Reponse processing involves invoking the completion
+callback that was provided by nfc_hci_msg_tx_work() when it sent the command.
+The completion callback will then wake the syscall context.
+
+Workflow receiving an HCI event or command
+------------------------------------------
+
+HCI commands or events are not dispatched from SMW context. Instead, they are
+queued to HCI rx_queue and will be dispatched from HCI rx worker
+context (MSGRXWQ). This is done this way to allow a cmd or event handler
+to also execute other commands (for example, handling the
+NFC_HCI_EVT_TARGET_DISCOVERED event from PN544 requires to issue an
+ANY_GET_PARAMETER to the reader A gate to get information on the target
+that was discovered).
+
+Typically, such an event will be propagated to NFC Core from MSGRXWQ context.
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
index 3201a7097e4d..98335b7a5337 100644
--- a/Documentation/sysctl/net.txt
+++ b/Documentation/sysctl/net.txt
@@ -43,6 +43,13 @@ Values :
         1 - enable the JIT
         2 - enable the JIT and ask the compiler to emit traces on kernel log.
 
+dev_weight
+--------------
+
+The maximum number of packets that kernel can handle on a NAPI interrupt,
+it's a Per-CPU variable.
+Default: 64
+
 rmem_default
 ------------