diff options
author | Viresh Kumar <viresh.kumar@linaro.org> | 2013-08-16 16:18:33 +0530 |
---|---|---|
committer | Gary S. Robertson <gary.robertson@linaro.org> | 2013-08-19 08:46:33 -0500 |
commit | 726a88c237f0fd8510e208ea367c614e48d1fa39 (patch) | |
tree | 995d1551d928077155266b1c1b72b73c05d8b2bf | |
parent | 91f8fa012c1e9fd79f2fcd8c07fc31caeafc6848 (diff) |
tty: serial: samsung: drop uart_port->lock before calling tty_flip_buffer_push()linux-lng-3.10.6-2013.08
The -rt patch triggers a lockdep warning for serial drivers if
tty_flip_buffer_push() is called with uart_port->lock locked. This never shows
up on UP kernels.
Release the port lock before calling tty_flip_buffer_push() and reacquire it
after the call.
Similar stuff was already done for few other drivers in the past, like:
commit 2389b272168ceec056ca1d8a870a97fa9c26e11a
Author: Thomas Gleixner <tglx@linutronix.de>
Date: Tue May 29 21:53:50 2007 +0100
[ARM] 4417/1: Serial: Fix AMBA drivers locking
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
-rw-r--r-- | drivers/tty/serial/samsung.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index 0c8a9fa2be6c..aaa0df1f2fc6 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -249,6 +249,8 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id) ufcon |= S3C2410_UFCON_RESETRX; wr_regl(port, S3C2410_UFCON, ufcon); rx_enabled(port) = 1; + spin_unlock_irqrestore(&port->lock, + flags); goto out; } continue; @@ -297,10 +299,11 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id) ignore_char: continue; } + + spin_unlock_irqrestore(&port->lock, flags); tty_flip_buffer_push(&port->state->port); out: - spin_unlock_irqrestore(&port->lock, flags); return IRQ_HANDLED; } |