[PATCH 09/12] ipack/devices/ipoctal: protect the channel data processing with a spinlock

From: Samuel Iglesias Gonsalvez
Date: Mon Dec 10 2012 - 06:01:35 EST


We protect important data such as TX buffer pointer, nb_bytes counter and status
registers of the device, from accessing several times at the same time.

Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@xxxxxxxxxx>
---
drivers/ipack/devices/ipoctal.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/ipack/devices/ipoctal.c b/drivers/ipack/devices/ipoctal.c
index d57ac61..8dff66e 100644
--- a/drivers/ipack/devices/ipoctal.c
+++ b/drivers/ipack/devices/ipoctal.c
@@ -191,6 +191,8 @@ static void ipoctal_irq_channel(struct ipoctal_channel *channel)
tty = tty_port_tty_get(&channel->tty_port);
if (!tty)
return;
+
+ spin_lock(&channel->lock);
/* The HW is organized in pair of channels. See which register we need
* to read from */
isr = ioread8(&channel->block_regs->r.isr);
@@ -216,6 +218,7 @@ static void ipoctal_irq_channel(struct ipoctal_channel *channel)

tty_flip_buffer_push(tty);
tty_kref_put(tty);
+ spin_unlock(&channel->lock);
}

static irqreturn_t ipoctal_irq_handler(void *arg)
--
1.7.10.4

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