diff options
Diffstat (limited to 'drivers/tty/serial/amba-pl011.c')
| -rw-r--r-- | drivers/tty/serial/amba-pl011.c | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 89ade213a1a9..55adaabb71ad 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -813,10 +813,8 @@ __acquires(&uap->port.lock) if (!uap->using_tx_dma) return; - /* Avoid deadlock with the DMA engine callback */ - spin_unlock(&uap->port.lock); - dmaengine_terminate_all(uap->dmatx.chan); - spin_lock(&uap->port.lock); + dmaengine_terminate_async(uap->dmatx.chan); + if (uap->dmatx.queued) { dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1, DMA_TO_DEVICE); @@ -2211,18 +2209,24 @@ pl011_console_write(struct console *co, const char *s, unsigned int count) { struct uart_amba_port *uap = amba_ports[co->index]; unsigned int old_cr = 0, new_cr; - unsigned long flags; + unsigned long flags = 0; int locked = 1; clk_enable(uap->clk); - local_irq_save(flags); + /* + * local_irq_save(flags); + * + * This local_irq_save() is nonsense. If we come in via sysrq + * handling then interrupts are already disabled. Aside of + * that the port.sysrq check is racy on SMP regardless. + */ if (uap->port.sysrq) locked = 0; else if (oops_in_progress) - locked = spin_trylock(&uap->port.lock); + locked = spin_trylock_irqsave(&uap->port.lock, flags); else - spin_lock(&uap->port.lock); + spin_lock_irqsave(&uap->port.lock, flags); /* * First save the CR then disable the interrupts @@ -2248,8 +2252,7 @@ pl011_console_write(struct console *co, const char *s, unsigned int count) pl011_write(old_cr, uap, REG_CR); if (locked) - spin_unlock(&uap->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&uap->port.lock, flags); clk_disable(uap->clk); } @@ -2587,6 +2590,7 @@ static int pl011_setup_port(struct device *dev, struct uart_amba_port *uap, uap->port.fifosize = uap->fifosize; uap->port.flags = UPF_BOOT_AUTOCONF; uap->port.line = index; + spin_lock_init(&uap->port.lock); amba_ports[index] = uap; |