[v2,1/1] pinctrl: mcp23s08: fix irq and irqchip setup order
diff mbox series

Message ID 20181002080646.10822-2-m.felsch@pengutronix.de
State New
Headers show
Series
  • Fixes for mcp23s08
Related show

Commit Message

Marco Felsch Oct. 2, 2018, 8:06 a.m. UTC
Since 'commit 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")' the
irq request isn't the last devm_* allocation. Without a deeper look at
the irq and testing this isn't a good solution. Since this driver relies
on the devm mechanism, requesting a interrupt should be the last thing
to avoid memory corruptions during unbinding.

'Commit 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")' fixed the
order for the interrupt-controller use case only. The
mcp23s08_irq_setup() must be split into two to fix it for the
interrupt-controller use case and to register the irq at last. So the
irq will be freed first during unbind.

Cc: stable@vger.kernel.org
Cc: Phil Reid <preid@electromag.com.au>
Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Dmitry Mastykin <mastichi@gmail.com>
Cc: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Fixes: 82039d244f87 ("pinctrl: mcp23s08: add pinconf support")
Fixes: 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 drivers/pinctrl/pinctrl-mcp23s08.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

Comments

Phil Reid Oct. 3, 2018, 1:24 a.m. UTC | #1
On 2/10/2018 4:06 PM, Marco Felsch wrote:
> Since 'commit 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")' the
> irq request isn't the last devm_* allocation. Without a deeper look at
> the irq and testing this isn't a good solution. Since this driver relies
> on the devm mechanism, requesting a interrupt should be the last thing
> to avoid memory corruptions during unbinding.
> 
> 'Commit 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")' fixed the
> order for the interrupt-controller use case only. The
> mcp23s08_irq_setup() must be split into two to fix it for the
> interrupt-controller use case and to register the irq at last. So the
> irq will be freed first during unbind.
> 
Tested with mcp23s18 with an irq.

Tested-by: Phil Reid <preid@electromag.com.au>

> Cc: stable@vger.kernel.org
> Cc: Phil Reid <preid@electromag.com.au>
> Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
> Cc: Dmitry Mastykin <mastichi@gmail.com>
> Cc: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
> Fixes: 82039d244f87 ("pinctrl: mcp23s08: add pinconf support")
> Fixes: 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")
> Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
> ---
>   drivers/pinctrl/pinctrl-mcp23s08.c | 13 ++++++++++++-
>   1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-mcp23s08.c b/drivers/pinctrl/pinctrl-mcp23s08.c
> index 4a8a8efadefa..cf73a403d22d 100644
> --- a/drivers/pinctrl/pinctrl-mcp23s08.c
> +++ b/drivers/pinctrl/pinctrl-mcp23s08.c
> @@ -636,6 +636,14 @@ static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
>   		return err;
>   	}
>   
> +	return 0;
> +}
> +
> +static int mcp23s08_irqchip_setup(struct mcp23s08 *mcp)
> +{
> +	struct gpio_chip *chip = &mcp->chip;
> +	int err;
> +
>   	err =  gpiochip_irqchip_add_nested(chip,
>   					   &mcp23s08_irq_chip,
>   					   0,
> @@ -912,7 +920,7 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
>   	}
>   
>   	if (mcp->irq && mcp->irq_controller) {
> -		ret = mcp23s08_irq_setup(mcp);
> +		ret = mcp23s08_irqchip_setup(mcp);
>   		if (ret)
>   			goto fail;
>   	}
> @@ -944,6 +952,9 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
>   		goto fail;
>   	}
>   
> +	if (mcp->irq)
> +		ret = mcp23s08_irq_setup(mcp);
> +
>   fail:
>   	if (ret < 0)
>   		dev_dbg(dev, "can't setup chip %d, --> %d\n", addr, ret);
>

Patch
diff mbox series

diff --git a/drivers/pinctrl/pinctrl-mcp23s08.c b/drivers/pinctrl/pinctrl-mcp23s08.c
index 4a8a8efadefa..cf73a403d22d 100644
--- a/drivers/pinctrl/pinctrl-mcp23s08.c
+++ b/drivers/pinctrl/pinctrl-mcp23s08.c
@@ -636,6 +636,14 @@  static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
 		return err;
 	}
 
+	return 0;
+}
+
+static int mcp23s08_irqchip_setup(struct mcp23s08 *mcp)
+{
+	struct gpio_chip *chip = &mcp->chip;
+	int err;
+
 	err =  gpiochip_irqchip_add_nested(chip,
 					   &mcp23s08_irq_chip,
 					   0,
@@ -912,7 +920,7 @@  static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 	}
 
 	if (mcp->irq && mcp->irq_controller) {
-		ret = mcp23s08_irq_setup(mcp);
+		ret = mcp23s08_irqchip_setup(mcp);
 		if (ret)
 			goto fail;
 	}
@@ -944,6 +952,9 @@  static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 		goto fail;
 	}
 
+	if (mcp->irq)
+		ret = mcp23s08_irq_setup(mcp);
+
 fail:
 	if (ret < 0)
 		dev_dbg(dev, "can't setup chip %d, --> %d\n", addr, ret);