Introduce __mt7601u_rr and __mt7601u_vendor_single_wr routines in order
to make mt7601u_rmw and mt7601u_rmc atomic. This patch does not fix a
reported issue but makes the usb access more robust to concurrent
operations on the same register since it is theoretically possible that
read and write accesses of mt7601u_rmw/mt7601u_rmc can be interleaved with
a different write operation on the same register.
Moreover using __mt7601u_rr and __mt7601u_vendor_single_wr in
mt7601u_rmw/mt7601u_rmc allows to grab vendor_req_mutex mutex once
instead of twice
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Acked-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Use the newly added linux/bitfield.h.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dinan Gunawardena <dinan.gunawardena@netronome.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
mac80211 requires that rx path does not run concurrently with
tx status reporting. Add a spinlock which will ensure that.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
mac80211 requires that rx path does not run concurrently with
tx status reporting. Since rx path is run in driver tasklet,
tx status cannot be reported directly from interrupt context
(there would be no way to lock it out).
Add tasklet for tx and move all possible code from irq handler
there.
Note: tx tasklet is needed because workqueue is queued very
rarely and that kills TCP performance.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
DMA to variables located on the stack is a bad idea.
For simplicity and to avoid frequent allocations create
a buffer inside the device structure. Protect this
buffer with vendor_req_mutex. Don't protect vendor
requests which don't use this buffer.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
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>