Patchwork I2C-mv64xxx.c: work around signals causing I2C transactions to be aborted

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Submitter Russell King
Date May 15, 2013, 2:33 p.m.
Message ID <E1UcclS-0001z3-PT@rmk-PC.arm.linux.org.uk>
Download mbox | patch
Permalink /patch/244092/
State Superseded
Headers show

Comments

Russell King - May 15, 2013, 2:33 p.m.
Do not use interruptible waits in an I2C driver; if a process uses
signals (eg, Xorg uses SIGALRM and SIGPIPE) then these signals can
cause the I2C driver to abort a transaction in progress by another
driver, which can cause that driver to fail.  I2C drivers are not
expected to abort transactions on signals.

Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
Mark Greer seems to be unreachable now; the address in this driver no
longer works, and there is no maintainer entry.  This patch has been
run on my Cubox (Marvell Dove) for quite a number of months without
ill effect.

 drivers/i2c/busses/i2c-mv64xxx.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

Patch

diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index 2e9d567..44d8045 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -252,7 +252,7 @@  mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
 		writel(drv_data->cntl_bits,
 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
 		drv_data->block = 0;
-		wake_up_interruptible(&drv_data->waitq);
+		wake_up(&drv_data->waitq);
 		break;
 
 	case MV64XXX_I2C_ACTION_CONTINUE:
@@ -300,7 +300,7 @@  mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
 		writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
 		drv_data->block = 0;
-		wake_up_interruptible(&drv_data->waitq);
+		wake_up(&drv_data->waitq);
 		break;
 
 	case MV64XXX_I2C_ACTION_INVALID:
@@ -315,7 +315,7 @@  mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
 		writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
 		drv_data->block = 0;
-		wake_up_interruptible(&drv_data->waitq);
+		wake_up(&drv_data->waitq);
 		break;
 	}
 }
@@ -381,7 +381,7 @@  mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data)
 	unsigned long	flags;
 	char		abort = 0;
 
-	time_left = wait_event_interruptible_timeout(drv_data->waitq,
+	time_left = wait_event_timeout(drv_data->waitq,
 		!drv_data->block, drv_data->adapter.timeout);
 
 	spin_lock_irqsave(&drv_data->lock, flags);