can: tcan4x5x: support resuming from rx interrupt signal

Implement the "wakeup-source" device tree property, so the chip is left
running when suspending, and its rx interrupt is used as a wakeup source
to resume operation.

Signed-off-by: Martin Hundebøll <martin@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/m_can/tcan4x5x-core.c b/drivers/net/can/m_can/tcan4x5x-core.c
index 71a9e1bec008cfaf9b6f5b5bfc0aad93350ae580..a42600dac70d4766f52c31ddd8135be3f66ae4a7 100644 (file)
--- a/drivers/net/can/m_can/tcan4x5x-core.c
+++ b/drivers/net/can/m_can/tcan4x5x-core.c
@@ -411,7 +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->pm_wake_source = device_property_read_bool(&spi->dev, "wakeup-source");
        mcan_class->can.clock.freq = freq;
        mcan_class->dev = &spi->dev;
        mcan_class->ops = &tcan4x5x_ops;
@@ -460,6 +460,9 @@ static int tcan4x5x_can_probe(struct spi_device *spi)
                goto out_power;
        }
 
+       if (mcan_class->pm_wake_source)
+               device_init_wakeup(&spi->dev, true);
+
        ret = m_can_class_register(mcan_class);
        if (ret) {
                dev_err(&spi->dev, "Failed registering m_can device %pe\n",
@@ -488,6 +491,29 @@ static void tcan4x5x_can_remove(struct spi_device *spi)
        m_can_class_free_dev(priv->cdev.net);
 }
 
+static int __maybe_unused tcan4x5x_suspend(struct device *dev)
+{
+       struct m_can_classdev *cdev = dev_get_drvdata(dev);
+       struct spi_device *spi = to_spi_device(dev);
+
+       if (cdev->pm_wake_source)
+               enable_irq_wake(spi->irq);
+
+       return m_can_class_suspend(dev);
+}
+
+static int __maybe_unused tcan4x5x_resume(struct device *dev)
+{
+       struct m_can_classdev *cdev = dev_get_drvdata(dev);
+       struct spi_device *spi = to_spi_device(dev);
+       int ret = m_can_class_resume(dev);
+
+       if (cdev->pm_wake_source)
+               disable_irq_wake(spi->irq);
+
+       return ret;
+}
+
 static const struct of_device_id tcan4x5x_of_match[] = {
        {
                .compatible = "ti,tcan4x5x",
@@ -506,11 +532,15 @@ static const struct spi_device_id tcan4x5x_id_table[] = {
 };
 MODULE_DEVICE_TABLE(spi, tcan4x5x_id_table);
 
+static const struct dev_pm_ops tcan4x5x_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(tcan4x5x_suspend, tcan4x5x_resume)
+};
+
 static struct spi_driver tcan4x5x_can_driver = {
        .driver = {
                .name = KBUILD_MODNAME,
                .of_match_table = tcan4x5x_of_match,
-               .pm = NULL,
+               .pm = &tcan4x5x_pm_ops,
        },
        .id_table = tcan4x5x_id_table,
        .probe = tcan4x5x_can_probe,