RE: [PATCH RESEND 1/1] mei: vsc: Unregister interrupt handler for system suspend

[Wu, Wentong]

> From: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
>
> Unregister the MEI VSC interrupt handler before system suspend and re-
> register it at system resume time. This mirrors implementation of other MEI
> devices.
> 
> This patch fixes the bug that causes continuous stream of MEI VSC errors
> after system resume.

Hi Tomas,

Could you please help review this patch? Thanks

BR
Wentong
> 
> Fixes: 386a766c4169 ("mei: Add MEI hardware support for IVSC device")
> Cc: stable@xxxxxxxxxxxxxxx # for 6.8
> Reported-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Wentong Wu <wentong.wu@xxxxxxxxx>
> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> ---
>  drivers/misc/mei/platform-vsc.c | 17 ++++++-
>  drivers/misc/mei/vsc-tp.c       | 84 +++++++++++++++++++++++----------
>  drivers/misc/mei/vsc-tp.h       |  3 ++
>  3 files changed, 78 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/misc/mei/platform-vsc.c b/drivers/misc/mei/platform-vsc.c
> index 8d303c6c0000..8db0fcf24e70 100644
> --- a/drivers/misc/mei/platform-vsc.c
> +++ b/drivers/misc/mei/platform-vsc.c
> @@ -402,25 +402,40 @@ static int mei_vsc_remove(struct platform_device
> *pdev)  static int mei_vsc_suspend(struct device *dev)  {
>  	struct mei_device *mei_dev = dev_get_drvdata(dev);
> +	struct mei_vsc_hw *hw = mei_dev_to_vsc_hw(mei_dev);
> 
>  	mei_stop(mei_dev);
> 
> +	mei_disable_interrupts(mei_dev);
> +
> +	vsc_tp_free_irq(hw->tp);
> +
>  	return 0;
>  }
> 
>  static int mei_vsc_resume(struct device *dev)  {
>  	struct mei_device *mei_dev = dev_get_drvdata(dev);
> +	struct mei_vsc_hw *hw = mei_dev_to_vsc_hw(mei_dev);
>  	int ret;
> 
> -	ret = mei_restart(mei_dev);
> +	ret = vsc_tp_request_irq(hw->tp);
>  	if (ret)
>  		return ret;
> 
> +	ret = mei_restart(mei_dev);
> +	if (ret)
> +		goto err_free;
> +
>  	/* start timer if stopped in suspend */
>  	schedule_delayed_work(&mei_dev->timer_work, HZ);
> 
>  	return 0;
> +
> +err_free:
> +	vsc_tp_free_irq(hw->tp);
> +
> +	return ret;
>  }
> 
>  static DEFINE_SIMPLE_DEV_PM_OPS(mei_vsc_pm_ops, mei_vsc_suspend,
> mei_vsc_resume); diff --git a/drivers/misc/mei/vsc-tp.c
> b/drivers/misc/mei/vsc-tp.c index 03486bebae09..870c70ef3bb8 100644
> --- a/drivers/misc/mei/vsc-tp.c
> +++ b/drivers/misc/mei/vsc-tp.c
> @@ -94,6 +94,27 @@ static const struct acpi_gpio_mapping
> vsc_tp_acpi_gpios[] = {
>  	{}
>  };
> 
> +static irqreturn_t vsc_tp_isr(int irq, void *data) {
> +	struct vsc_tp *tp = data;
> +
> +	atomic_inc(&tp->assert_cnt);
> +
> +	wake_up(&tp->xfer_wait);
> +
> +	return IRQ_WAKE_THREAD;
> +}
> +
> +static irqreturn_t vsc_tp_thread_isr(int irq, void *data) {
> +	struct vsc_tp *tp = data;
> +
> +	if (tp->event_notify)
> +		tp->event_notify(tp->event_notify_context);
> +
> +	return IRQ_HANDLED;
> +}
> +
>  /* wakeup firmware and wait for response */  static int
> vsc_tp_wakeup_request(struct vsc_tp *tp)  { @@ -383,6 +404,37 @@ int
> vsc_tp_register_event_cb(struct vsc_tp *tp, vsc_tp_event_cb_t event_cb,  }
> EXPORT_SYMBOL_NS_GPL(vsc_tp_register_event_cb, VSC_TP);
> 
> +/**
> + * vsc_tp_request_irq - request irq for vsc_tp device
> + * @tp: vsc_tp device handle
> + */
> +int vsc_tp_request_irq(struct vsc_tp *tp) {
> +	struct spi_device *spi = tp->spi;
> +	struct device *dev = &spi->dev;
> +	int ret;
> +
> +	irq_set_status_flags(spi->irq, IRQ_DISABLE_UNLAZY);
> +	ret = request_threaded_irq(spi->irq, vsc_tp_isr, vsc_tp_thread_isr,
> +				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> +				   dev_name(dev), tp);
> +	if (ret)
> +		return ret;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_NS_GPL(vsc_tp_request_irq, VSC_TP);
> +
> +/**
> + * vsc_tp_free_irq - free irq for vsc_tp device
> + * @tp: vsc_tp device handle
> + */
> +void vsc_tp_free_irq(struct vsc_tp *tp) {
> +	free_irq(tp->spi->irq, tp);
> +}
> +EXPORT_SYMBOL_NS_GPL(vsc_tp_free_irq, VSC_TP);
> +
>  /**
>   * vsc_tp_intr_synchronize - synchronize vsc_tp interrupt
>   * @tp: vsc_tp device handle
> @@ -413,27 +465,6 @@ void vsc_tp_intr_disable(struct vsc_tp *tp)  }
> EXPORT_SYMBOL_NS_GPL(vsc_tp_intr_disable, VSC_TP);
> 
> -static irqreturn_t vsc_tp_isr(int irq, void *data) -{
> -	struct vsc_tp *tp = data;
> -
> -	atomic_inc(&tp->assert_cnt);
> -
> -	wake_up(&tp->xfer_wait);
> -
> -	return IRQ_WAKE_THREAD;
> -}
> -
> -static irqreturn_t vsc_tp_thread_isr(int irq, void *data) -{
> -	struct vsc_tp *tp = data;
> -
> -	if (tp->event_notify)
> -		tp->event_notify(tp->event_notify_context);
> -
> -	return IRQ_HANDLED;
> -}
> -
>  static int vsc_tp_match_any(struct acpi_device *adev, void *data)  {
>  	struct acpi_device **__adev = data;
> @@ -485,10 +516,9 @@ static int vsc_tp_probe(struct spi_device *spi)
>  	tp->spi = spi;
> 
>  	irq_set_status_flags(spi->irq, IRQ_DISABLE_UNLAZY);
> -	ret = devm_request_threaded_irq(dev, spi->irq, vsc_tp_isr,
> -					vsc_tp_thread_isr,
> -					IRQF_TRIGGER_FALLING |
> IRQF_ONESHOT,
> -					dev_name(dev), tp);
> +	ret = request_threaded_irq(spi->irq, vsc_tp_isr, vsc_tp_thread_isr,
> +				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> +				   dev_name(dev), tp);
>  	if (ret)
>  		return ret;
> 
> @@ -522,6 +552,8 @@ static int vsc_tp_probe(struct spi_device *spi)
>  err_destroy_lock:
>  	mutex_destroy(&tp->mutex);
> 
> +	free_irq(spi->irq, tp);
> +
>  	return ret;
>  }
> 
> @@ -532,6 +564,8 @@ static void vsc_tp_remove(struct spi_device *spi)
>  	platform_device_unregister(tp->pdev);
> 
>  	mutex_destroy(&tp->mutex);
> +
> +	free_irq(spi->irq, tp);
>  }
> 
>  static const struct acpi_device_id vsc_tp_acpi_ids[] = { diff --git
> a/drivers/misc/mei/vsc-tp.h b/drivers/misc/mei/vsc-tp.h index
> f9513ddc3e40..14ca195cbddc 100644
> --- a/drivers/misc/mei/vsc-tp.h
> +++ b/drivers/misc/mei/vsc-tp.h
> @@ -37,6 +37,9 @@ int vsc_tp_xfer(struct vsc_tp *tp, u8 cmd, const void
> *obuf, size_t olen,  int vsc_tp_register_event_cb(struct vsc_tp *tp,
> vsc_tp_event_cb_t event_cb,
>  			     void *context);
> 
> +int vsc_tp_request_irq(struct vsc_tp *tp); void vsc_tp_free_irq(struct
> +vsc_tp *tp);
> +
>  void vsc_tp_intr_enable(struct vsc_tp *tp);  void vsc_tp_intr_disable(struct
> vsc_tp *tp);  void vsc_tp_intr_synchronize(struct vsc_tp *tp);
> --
> 2.39.2