[PATCH 3.16.y-ckt 130/165] Revert "i2c: core: Dispose OF IRQ mapping at client removal time"

[Luis Henriques <luis.henriques@canonical.com>]

3.16.7-ckt9 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jakub Kicinski <kubakici@wp.pl>

commit a49445727014216703a3c28ccee4cef36d41571e upstream.

This reverts commit e4df3a0b6228
("i2c: core: Dispose OF IRQ mapping at client removal time")

Calling irq_dispose_mapping() will destroy the mapping and disassociate
the IRQ from the IRQ chip to which it belongs. Keeping it is OK, because
existent mappings are reused properly.

Also, this commit breaks drivers using devm* for IRQ management on
OF-based systems because devm* cleanup happens in device code, after
bus's remove() method returns.

Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Reported-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
[wsa: updated the commit message with findings fromt the other bug report]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: e4df3a0b6228
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 drivers/i2c/i2c-core.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 4716eb0bddcd..7c7f4b856bad 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -297,9 +297,6 @@ static int i2c_device_remove(struct device *dev)
 		status = driver->remove(client);
 	}
 
-	if (dev->of_node)
-		irq_dispose_mapping(client->irq);
-
 	acpi_dev_pm_detach(&client->dev, true);
 	return status;
 }