add mt7601u driver

Add support for the simplest of MediaTek Wi-Fi devices - MT7601U.
It is a single stream bgn chip with no bells or whistles.
This driver is partially based on Felix's mt76 but IMHO it doesn't
make sense to merge the two right now because MT7601U is a design
somewhere between old Ralink devices and new Mediatek chips.  There
wouldn't be all that much code sharing with the devices mt76 supports.
Situation may obviously change when someone decides to extend m76 with
support for the more recent USB dongles.

The driver supports only station mode.  I'm hoping to add AP support
when time allows.

This driver sat on GitHub for quite a while and got some testing there:
http://github.com/kuba-moo/mt7601u

Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

1 files changed, 390 insertions, 0 deletions

diff --git a/drivers/net/wireless/mediatek/mt7601u/mt7601u.h b/drivers/net/wireless/mediatek/mt7601u/mt7601u.h
new file mode 100644
index 000000000000..9102be6b95cb
--- /dev/null
+++ b/drivers/net/wireless/mediatek/mt7601u/mt7601u.h
@@ -0,0 +1,390 @@
+/*
+ * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2015 Jakub Kicinski <kubakici@wp.pl>
+ *
+ * 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 published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef MT7601U_H
+#define MT7601U_H
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/usb.h>
+#include <linux/completion.h>
+#include <net/mac80211.h>
+#include <linux/debugfs.h>
+
+#include "regs.h"
+#include "util.h"
+
+#define MT_CALIBRATE_INTERVAL		(4 * HZ)
+
+#define MT_FREQ_CAL_INIT_DELAY		(30 * HZ)
+#define MT_FREQ_CAL_CHECK_INTERVAL	(10 * HZ)
+#define MT_FREQ_CAL_ADJ_INTERVAL	(HZ / 2)
+
+#define MT_BBP_REG_VERSION		0x00
+
+#define MT_USB_AGGR_SIZE_LIMIT		28 /* * 1024B */
+#define MT_USB_AGGR_TIMEOUT		0x80 /* * 33ns */
+#define MT_RX_ORDER			3
+#define MT_RX_URB_SIZE			(PAGE_SIZE << MT_RX_ORDER)
+
+struct mt7601u_dma_buf {
+	struct urb *urb;
+	void *buf;
+	dma_addr_t dma;
+	size_t len;
+};
+
+struct mt7601u_mcu {
+	struct mutex mutex;
+
+	u8 msg_seq;
+
+	struct mt7601u_dma_buf resp;
+	struct completion resp_cmpl;
+};
+
+struct mt7601u_freq_cal {
+	struct delayed_work work;
+	u8 freq;
+	bool enabled;
+	bool adjusting;
+};
+
+struct mac_stats {
+	u64 rx_stat[6];
+	u64 tx_stat[6];
+	u64 aggr_stat[2];
+	u64 aggr_n[32];
+	u64 zero_len_del[2];
+};
+
+#define N_RX_ENTRIES	16
+struct mt7601u_rx_queue {
+	struct mt7601u_dev *dev;
+
+	struct mt7601u_dma_buf_rx {
+		struct urb *urb;
+		struct page *p;
+	} e[N_RX_ENTRIES];
+
+	unsigned int start;
+	unsigned int end;
+	unsigned int entries;
+	unsigned int pending;
+};
+
+#define N_TX_ENTRIES	64
+
+struct mt7601u_tx_queue {
+	struct mt7601u_dev *dev;
+
+	struct mt7601u_dma_buf_tx {
+		struct urb *urb;
+		struct sk_buff *skb;
+	} e[N_TX_ENTRIES];
+
+	unsigned int start;
+	unsigned int end;
+	unsigned int entries;
+	unsigned int used;
+	unsigned int fifo_seq;
+};
+
+/* WCID allocation:
+ *     0: mcast wcid
+ *     1: bssid wcid
+ *  1...: STAs
+ * ...7e: group wcids
+ *    7f: reserved
+ */
+#define N_WCIDS		128
+#define GROUP_WCID(idx)	(N_WCIDS - 2 - idx)
+
+struct mt7601u_eeprom_params;
+
+#define MT_EE_TEMPERATURE_SLOPE		39
+#define MT_FREQ_OFFSET_INVALID		-128
+
+enum mt_temp_mode {
+	MT_TEMP_MODE_NORMAL,
+	MT_TEMP_MODE_HIGH,
+	MT_TEMP_MODE_LOW,
+};
+
+enum mt_bw {
+	MT_BW_20,
+	MT_BW_40,
+};
+
+enum {
+	MT7601U_STATE_INITIALIZED,
+	MT7601U_STATE_REMOVED,
+	MT7601U_STATE_WLAN_RUNNING,
+	MT7601U_STATE_MCU_RUNNING,
+	MT7601U_STATE_SCANNING,
+	MT7601U_STATE_READING_STATS,
+	MT7601U_STATE_MORE_STATS,
+};
+
+/**
+ * struct mt7601u_dev - adapter structure
+ * @lock:		protects @wcid->tx_rate.
+ * @tx_lock:		protects @tx_q and changes of MT7601U_STATE_*_STATS
+			flags in @state.
+ * @rx_lock:		protects @rx_q.
+ * @con_mon_lock:	protects @ap_bssid, @bcn_*, @avg_rssi.
+ * @mutex:		ensures exclusive access from mac80211 callbacks.
+ * @vendor_req_mutex:	ensures atomicity of vendor requests.
+ * @reg_atomic_mutex:	ensures atomicity of indirect register accesses
+ *			(accesses to RF and BBP).
+ * @hw_atomic_mutex:	ensures exclusive access to HW during critical
+ *			operations (power management, channel switch).
+ */
+struct mt7601u_dev {
+	struct ieee80211_hw *hw;
+	struct device *dev;
+
+	unsigned long state;
+
+	struct mutex mutex;
+
+	unsigned long wcid_mask[N_WCIDS / BITS_PER_LONG];
+
+	struct cfg80211_chan_def chandef;
+	struct ieee80211_supported_band *sband_2g;
+
+	struct mt7601u_mcu mcu;
+
+	struct delayed_work cal_work;
+	struct delayed_work mac_work;
+
+	struct workqueue_struct *stat_wq;
+	struct delayed_work stat_work;
+
+	struct mt76_wcid *mon_wcid;
+	struct mt76_wcid __rcu *wcid[N_WCIDS];
+
+	spinlock_t lock;
+
+	const u16 *beacon_offsets;
+
+	u8 macaddr[ETH_ALEN];
+	struct mt7601u_eeprom_params *ee;
+
+	struct mutex vendor_req_mutex;
+	struct mutex reg_atomic_mutex;
+	struct mutex hw_atomic_mutex;
+
+	u32 rxfilter;
+	u32 debugfs_reg;
+
+	u8 out_eps[8];
+	u8 in_eps[8];
+	u16 out_max_packet;
+	u16 in_max_packet;
+
+	/* TX */
+	spinlock_t tx_lock;
+	struct mt7601u_tx_queue *tx_q;
+
+	atomic_t avg_ampdu_len;
+
+	/* RX */
+	spinlock_t rx_lock;
+	struct tasklet_struct rx_tasklet;
+	struct mt7601u_rx_queue rx_q;
+
+	/* Connection monitoring things */
+	spinlock_t con_mon_lock;
+	u8 ap_bssid[ETH_ALEN];
+
+	s8 bcn_freq_off;
+	u8 bcn_phy_mode;
+
+	int avg_rssi; /* starts at 0 and converges */
+
+	u8 agc_save;
+
+	struct mt7601u_freq_cal freq_cal;
+
+	bool tssi_read_trig;
+
+	s8 tssi_init;
+	s8 tssi_init_hvga;
+	s16 tssi_init_hvga_offset_db;
+
+	int prev_pwr_diff;
+
+	enum mt_temp_mode temp_mode;
+	int curr_temp;
+	int dpd_temp;
+	s8 raw_temp;
+	bool pll_lock_protect;
+
+	u8 bw;
+	bool chan_ext_below;
+
+	/* PA mode */
+	u32 rf_pa_mode[2];
+
+	struct mac_stats stats;
+};
+
+struct mt7601u_tssi_params {
+	char tssi0;
+	int trgt_power;
+};
+
+struct mt76_wcid {
+	u8 idx;
+	u8 hw_key_idx;
+
+	u16 tx_rate;
+	bool tx_rate_set;
+	u8 tx_rate_nss;
+};
+
+struct mt76_vif {
+	u8 idx;
+
+	struct mt76_wcid group_wcid;
+};
+
+struct mt76_sta {
+	struct mt76_wcid wcid;
+	u16 agg_ssn[IEEE80211_NUM_TIDS];
+};
+
+struct mt76_reg_pair {
+	u32 reg;
+	u32 value;
+};
+
+struct mt7601u_rxwi;
+
+extern const struct ieee80211_ops mt7601u_ops;
+
+void mt7601u_init_debugfs(struct mt7601u_dev *dev);
+
+u32 mt7601u_rr(struct mt7601u_dev *dev, u32 offset);
+void mt7601u_wr(struct mt7601u_dev *dev, u32 offset, u32 val);
+u32 mt7601u_rmw(struct mt7601u_dev *dev, u32 offset, u32 mask, u32 val);
+u32 mt7601u_rmc(struct mt7601u_dev *dev, u32 offset, u32 mask, u32 val);
+void mt7601u_wr_copy(struct mt7601u_dev *dev, u32 offset,
+		     const void *data, int len);
+
+int mt7601u_wait_asic_ready(struct mt7601u_dev *dev);
+bool mt76_poll(struct mt7601u_dev *dev, u32 offset, u32 mask, u32 val,
+	       int timeout);
+bool mt76_poll_msec(struct mt7601u_dev *dev, u32 offset, u32 mask, u32 val,
+		    int timeout);
+
+/* Compatibility with mt76 */
+#define mt76_rmw_field(_dev, _reg, _field, _val)	\
+	mt76_rmw(_dev, _reg, _field, MT76_SET(_field, _val))
+
+static inline u32 mt76_rr(struct mt7601u_dev *dev, u32 offset)
+{
+	return mt7601u_rr(dev, offset);
+}
+
+static inline void mt76_wr(struct mt7601u_dev *dev, u32 offset, u32 val)
+{
+	return mt7601u_wr(dev, offset, val);
+}
+
+static inline u32
+mt76_rmw(struct mt7601u_dev *dev, u32 offset, u32 mask, u32 val)
+{
+	return mt7601u_rmw(dev, offset, mask, val);
+}
+
+static inline u32 mt76_set(struct mt7601u_dev *dev, u32 offset, u32 val)
+{
+	return mt76_rmw(dev, offset, 0, val);
+}
+
+static inline u32 mt76_clear(struct mt7601u_dev *dev, u32 offset, u32 val)
+{
+	return mt76_rmw(dev, offset, val, 0);
+}
+
+int mt7601u_write_reg_pairs(struct mt7601u_dev *dev, u32 base,
+			    const struct mt76_reg_pair *data, int len);
+int mt7601u_burst_write_regs(struct mt7601u_dev *dev, u32 offset,
+			     const u32 *data, int n);
+void mt7601u_addr_wr(struct mt7601u_dev *dev, const u32 offset, const u8 *addr);
+
+/* Init */
+struct mt7601u_dev *mt7601u_alloc_device(struct device *dev);
+int mt7601u_init_hardware(struct mt7601u_dev *dev);
+int mt7601u_register_device(struct mt7601u_dev *dev);
+void mt7601u_cleanup(struct mt7601u_dev *dev);
+
+int mt7601u_mac_start(struct mt7601u_dev *dev);
+void mt7601u_mac_stop(struct mt7601u_dev *dev);
+
+/* PHY */
+int mt7601u_phy_init(struct mt7601u_dev *dev);
+int mt7601u_wait_bbp_ready(struct mt7601u_dev *dev);
+void mt7601u_set_rx_path(struct mt7601u_dev *dev, u8 path);
+void mt7601u_set_tx_dac(struct mt7601u_dev *dev, u8 path);
+int mt7601u_bbp_set_bw(struct mt7601u_dev *dev, int bw);
+void mt7601u_agc_save(struct mt7601u_dev *dev);
+void mt7601u_agc_restore(struct mt7601u_dev *dev);
+int mt7601u_phy_set_channel(struct mt7601u_dev *dev,
+			    struct cfg80211_chan_def *chandef);
+void mt7601u_phy_recalibrate_after_assoc(struct mt7601u_dev *dev);
+int mt7601u_phy_get_rssi(struct mt7601u_dev *dev,
+			 struct mt7601u_rxwi *rxwi, u16 rate);
+void mt7601u_phy_con_cal_onoff(struct mt7601u_dev *dev,
+			       struct ieee80211_bss_conf *info);
+
+/* MAC */
+void mt7601u_mac_work(struct work_struct *work);
+void mt7601u_mac_set_protection(struct mt7601u_dev *dev, bool legacy_prot,
+				int ht_mode);
+void mt7601u_mac_set_short_preamble(struct mt7601u_dev *dev, bool short_preamb);
+void mt7601u_mac_config_tsf(struct mt7601u_dev *dev, bool enable, int interval);
+void
+mt7601u_mac_wcid_setup(struct mt7601u_dev *dev, u8 idx, u8 vif_idx, u8 *mac);
+void mt7601u_mac_set_ampdu_factor(struct mt7601u_dev *dev);
+
+/* TX */
+void mt7601u_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control,
+		struct sk_buff *skb);
+int mt7601u_conf_tx(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+		    u16 queue, const struct ieee80211_tx_queue_params *params);
+void mt7601u_tx_status(struct mt7601u_dev *dev, struct sk_buff *skb);
+void mt7601u_tx_stat(struct work_struct *work);
+
+/* util */
+void mt76_remove_hdr_pad(struct sk_buff *skb);
+int mt76_insert_hdr_pad(struct sk_buff *skb);
+
+u32 mt7601u_bbp_set_ctrlch(struct mt7601u_dev *dev, bool below);
+
+static inline u32 mt7601u_mac_set_ctrlch(struct mt7601u_dev *dev, bool below)
+{
+	return mt7601u_rmc(dev, MT_TX_BAND_CFG, 1, below);
+}
+
+int mt7601u_dma_init(struct mt7601u_dev *dev);
+void mt7601u_dma_cleanup(struct mt7601u_dev *dev);
+
+int mt7601u_dma_enqueue_tx(struct mt7601u_dev *dev, struct sk_buff *skb,
+			   struct mt76_wcid *wcid, int hw_q);
+
+#endif