Re: [PATCH v2] ipmi:bt-bmc: Fix error handling and status check

From: Corey Minyard
Date: Sat Apr 18 2020 - 09:51:23 EST


On Sat, Apr 18, 2020 at 04:02:29PM +0800, Tang Bin wrote:
> If the function platform_get_irq() failed, the negative
> value returned will not be detected here. So fix error
> handling in bt_bmc_config_irq(). And if devm_request_irq()
> failed, 'bt_bmc->irq' is assigned to zero maybe redundant,
> it may be more suitable for using the correct negative values
> to make the status check in the function bt_bmc_remove().

You need to mention changing platform_get_irq to
platform_get_irq_optional in the header.

Another comment inline below.

Otherwise, this looks good.

>
> Signed-off-by: Shengju Zhang <zhangshengju@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Tang Bin <tangbin@xxxxxxxxxxxxxxxxxxxx>
> ---
> Changes from v1
> - fix the code of status check
> ---
> drivers/char/ipmi/bt-bmc.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/char/ipmi/bt-bmc.c b/drivers/char/ipmi/bt-bmc.c
> index cd0349bff..33d3a5d50 100644
> --- a/drivers/char/ipmi/bt-bmc.c
> +++ b/drivers/char/ipmi/bt-bmc.c
> @@ -399,15 +399,14 @@ static int bt_bmc_config_irq(struct bt_bmc *bt_bmc,
> struct device *dev = &pdev->dev;
> int rc;
>
> - bt_bmc->irq = platform_get_irq(pdev, 0);
> - if (!bt_bmc->irq)
> - return -ENODEV;
> + bt_bmc->irq = platform_get_irq_optional(pdev, 0);
> + if (bt_bmc->irq < 0)
> + return bt_bmc->irq;
>
> rc = devm_request_irq(dev, bt_bmc->irq, bt_bmc_irq, IRQF_SHARED,
> DEVICE_NAME, bt_bmc);
> if (rc < 0) {
> dev_warn(dev, "Unable to request IRQ %d\n", bt_bmc->irq);
> - bt_bmc->irq = 0;

You need to set this to rc. Otherwise it will remain the interrupt
number assigned by platform_get_irq_optional().

-corey

> return rc;
> }
>
> @@ -474,7 +473,7 @@ static int bt_bmc_probe(struct platform_device *pdev)
>
> bt_bmc_config_irq(bt_bmc, pdev);
>
> - if (bt_bmc->irq) {
> + if (bt_bmc->irq >= 0) {
> dev_info(dev, "Using IRQ %d\n", bt_bmc->irq);
> } else {
> dev_info(dev, "No IRQ; using timer\n");
> @@ -500,7 +499,7 @@ static int bt_bmc_remove(struct platform_device *pdev)
> struct bt_bmc *bt_bmc = dev_get_drvdata(&pdev->dev);
>
> misc_deregister(&bt_bmc->miscdev);
> - if (!bt_bmc->irq)
> + if (bt_bmc->irq < 0)
> del_timer_sync(&bt_bmc->poll_timer);
> return 0;
> }
> --
> 2.20.1.windows.1
>
>
>