[PATCH v2] spi: fix possible deadlock between internal bus locks and bus_lock_flag

[Kevin Hilman]

Heiko Stübner <heiko at sntech.de> writes:

> External users may use spi_bus_lock to get exclusive access. This will
> also grab the bus_lock_mutex and may therefore result in a deadlock if
> __spi_pump_messages also tries to get the mutex.
>
> Therefore adapt spi_pump_messages as well as spi_sync to preset the
> bus_locked parameter according to the master->bus_lock_flag.
>
> Fixes: 49023d2e4ead ("spi: core: Fix deadlock when sending messages")
> Signed-off-by: Heiko Stuebner <heiko at sntech.de>

Tested on rk3288-veyron-jerry and verified that it fixes the boot
failure I reported.

Tested-by: Kevin Hilman <khilman at baylibre.com>

Kevin