Hi Martin,
On Mon, Nov 13, 2023 at 02:14:50PM +0100, Martin Hundebøll wrote:
> Add a flag to the device class structure that leaves the chip in a
> running state with rx interrupt enabled, so that an m_can device driver
> can configure and use the interrupt as a wakeup source.
>
> Signed-off-by: Martin Hundebøll <martin@xxxxxxxxxx>
> ---
>
> Change in v3:
> * Replaced the added function parameter with a property in
> struct m_can_classdev.
>
> Changes in v2:
> * Fixed comment formatting
> * Updated m_can_class_{suspend,resume} calls in m_can_pci.c too
> * Skipped calling m_can_start() when resuming a wake-source device
>
> drivers/net/can/m_can/m_can.c | 22 +++++++++++++++++-----
> drivers/net/can/m_can/m_can.h | 1 +
> drivers/net/can/m_can/m_can_pci.c | 1 +
> drivers/net/can/m_can/m_can_platform.c | 1 +
> drivers/net/can/m_can/tcan4x5x-core.c | 1 +
> 5 files changed, 21 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
> index b351597f594b..55df50580480 100644
> --- a/drivers/net/can/m_can/m_can.c
> +++ b/drivers/net/can/m_can/m_can.c
> @@ -2392,7 +2392,15 @@ int m_can_class_suspend(struct device *dev)
> if (netif_running(ndev)) {
> netif_stop_queue(ndev);
> netif_device_detach(ndev);
> - m_can_stop(ndev);
> +
> + /* leave the chip running with rx interrupt enabled if it is
> + * used as a wake-up source.
> + */
> + if (cdev->pm_wake_source)
> + m_can_write(cdev, M_CAN_IE, IR_RF0N);
> + else
> + m_can_stop(ndev);
> +
> m_can_clk_stop(cdev);
> }
>
> @@ -2419,11 +2427,15 @@ int m_can_class_resume(struct device *dev)
> ret = m_can_clk_start(cdev);
> if (ret)
> return ret;
> - ret = m_can_start(ndev);
> - if (ret) {
> - m_can_clk_stop(cdev);
>
> - return ret;
> + if (cdev->pm_wake_source) {
> + m_can_write(cdev, M_CAN_IE, cdev->active_interrupts);
> + } else {
> + ret = m_can_start(ndev);
There is one space too much here.
> + if (ret) {
> + m_can_clk_stop(cdev);
> + return ret;
> + }
> }
>
> netif_device_attach(ndev);
> diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
> index 2986c4ce0b2f..3a9edc292593 100644
> --- a/drivers/net/can/m_can/m_can.h
> +++ b/drivers/net/can/m_can/m_can.h
> @@ -97,6 +97,7 @@ struct m_can_classdev {
> u32 irqstatus;
>
> int pm_clock_support;
> + int pm_wake_source;
Can you avoid this new variable by using device_can_wakeup() and/or
device_may_wakeup() to check if the device is capable to wake up and if
wakeup is actually enabled?
Best,
Markus
> int is_peripheral;
>
> // Cached M_CAN_IE register content
> diff --git a/drivers/net/can/m_can/m_can_pci.c b/drivers/net/can/m_can/m_can_pci.c
> index f2219aa2824b..45400de4163d 100644
> --- a/drivers/net/can/m_can/m_can_pci.c
> +++ b/drivers/net/can/m_can/m_can_pci.c
> @@ -125,6 +125,7 @@ static int m_can_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
> mcan_class->dev = &pci->dev;
> mcan_class->net->irq = pci_irq_vector(pci, 0);
> mcan_class->pm_clock_support = 1;
> + mcan_class->pm_wake_source = 0;
> mcan_class->can.clock.freq = id->driver_data;
> mcan_class->ops = &m_can_pci_ops;
>
> diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
> index ab1b8211a61c..df0367124b4c 100644
> --- a/drivers/net/can/m_can/m_can_platform.c
> +++ b/drivers/net/can/m_can/m_can_platform.c
> @@ -139,6 +139,7 @@ static int m_can_plat_probe(struct platform_device *pdev)
>
> mcan_class->net->irq = irq;
> mcan_class->pm_clock_support = 1;
> + mcan_class->pm_wake_source = 0;
> mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk);
> mcan_class->dev = &pdev->dev;
> mcan_class->transceiver = transceiver;
> diff --git a/drivers/net/can/m_can/tcan4x5x-core.c b/drivers/net/can/m_can/tcan4x5x-core.c
> index 8a4143809d33..870ab4aef610 100644
> --- a/drivers/net/can/m_can/tcan4x5x-core.c
> +++ b/drivers/net/can/m_can/tcan4x5x-core.c
> @@ -411,6 +411,7 @@ static int tcan4x5x_can_probe(struct spi_device *spi)
> priv->spi = spi;
>
> mcan_class->pm_clock_support = 0;
> + mcan_class->pm_wake_source = 0;
> mcan_class->can.clock.freq = freq;
> mcan_class->dev = &spi->dev;
> mcan_class->ops = &tcan4x5x_ops;
> --
> 2.42.0
>
