Re: [PATCH] mfd: 88pm80x: refine irq bit operation

zhouqiao
2015-06-05T07:53:24Z

On 05/15/2015 07:10 PM, Qiao Zhou wrote:
> Set_bit/clear_bit for wu_flag may be corrupted if irq > 5(or 6 for
> aarch64). The maximum irq number from 88pm80x chip series is 24.
> Here we refine the code to protect the potential memory corruption.
>
> Also change wu_flag to wakeup_flag for easier understanding.
>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> Signed-off-by: Qiao Zhou <zhouqiao@marvell.com>
> ---
> drivers/mfd/88pm80x.c | 4 ++--
> include/linux/mfd/88pm80x.h | 19 ++++++++++++++++---
> 2 files changed, 18 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/mfd/88pm80x.c b/drivers/mfd/88pm80x.c
> index 5e72f65..e1d803a 100644
> --- a/drivers/mfd/88pm80x.c
> +++ b/drivers/mfd/88pm80x.c
> @@ -136,7 +136,7 @@ static int pm80x_suspend(struct device *dev)
> struct i2c_client *client = container_of(dev, struct i2c_client, dev);
> struct pm80x_chip *chip = i2c_get_clientdata(client);
>
> - if (chip && chip->wu_flag)
> + if (chip && chip->wakeup_flag)
> if (device_may_wakeup(chip->dev))
> enable_irq_wake(chip->irq);
>
> @@ -148,7 +148,7 @@ static int pm80x_resume(struct device *dev)
> struct i2c_client *client = container_of(dev, struct i2c_client, dev);
> struct pm80x_chip *chip = i2c_get_clientdata(client);
>
> - if (chip && chip->wu_flag)
> + if (chip && chip->wakeup_flag)
> if (device_may_wakeup(chip->dev))
> disable_irq_wake(chip->irq);
>
> diff --git a/include/linux/mfd/88pm80x.h b/include/linux/mfd/88pm80x.h
> index 97cb283..1bca7eb 100644
> --- a/include/linux/mfd/88pm80x.h
> +++ b/include/linux/mfd/88pm80x.h
> @@ -276,6 +276,9 @@ enum {
> #define PM805_EARPHONE_SETTING (0x29)
> #define PM805_AUTO_SEQ_SETTING (0x2A)
>
> +/* supported 24 sub-irq */
> +#define PM80x_MAX_IRQ 24
> +
> struct pm80x_rtc_pdata {
> int vrtc;
> int rtc_wakeup;
> @@ -301,7 +304,7 @@ struct pm80x_chip {
> int type;
> int irq;
> int irq_mode;
> - unsigned long wu_flag;
> + unsigned long wakeup_flag;
> spinlock_t lock;
> };
>
> @@ -348,8 +351,13 @@ static inline int pm80x_dev_suspend(struct device *dev)
> struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
> int irq = platform_get_irq(pdev, 0);
>
> + if (irq < 0 || irq >= PM80x_MAX_IRQ) {
> + dev_err(dev, "Invalid irq %d\n", irq);
> + return 0;
> + }
> +
> if (device_may_wakeup(dev))
> - set_bit((1 << irq), &chip->wu_flag);
> + set_bit(irq, &chip->wakeup_flag);
>
> return 0;
> }
> @@ -360,8 +368,13 @@ static inline int pm80x_dev_resume(struct device *dev)
> struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
> int irq = platform_get_irq(pdev, 0);
>
> + if (irq < 0 || irq >= PM80x_MAX_IRQ) {
> + dev_err(dev, "Invalid irq %d\n", irq);
> + return 0;
> + }
> +
> if (device_may_wakeup(dev))
> - clear_bit((1 << irq), &chip->wu_flag);
> + clear_bit(irq, &chip->wakeup_flag);
>
> return 0;
> }
Hi Dan, Jones

could you help to review this patch?

--
Best Regards
Qiao