From: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> In order to support a flavor of the sja1000 which sometimes freezes, it will be needed upon certain interrupts to perform a soft reset. The soft reset operation takes a bit of time, so better not do it within the hard interrupt handler but rather in a threaded handler. Let's prepare the possibility for sja1000_err() to request "interrupting" the current flow and request the threaded handler to be run while keeping the interrupt line low. There is no functional change. Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> Link: https://lore.kernel.org/all/20230616134553.2786391-1-miquel.raynal@xxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- drivers/net/can/sja1000/sja1000.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index aac5956e4a53..4719806e3a9f 100644 --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -501,7 +501,8 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) struct sja1000_priv *priv = netdev_priv(dev); struct net_device_stats *stats = &dev->stats; uint8_t isrc, status; - int n = 0; + irqreturn_t ret = 0; + int n = 0, err; if (priv->pre_irq) priv->pre_irq(priv); @@ -546,19 +547,23 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) } if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { /* error interrupt */ - if (sja1000_err(dev, isrc, status)) + err = sja1000_err(dev, isrc, status); + if (err) break; } n++; } out: + if (!ret) + ret = (n) ? IRQ_HANDLED : IRQ_NONE; + if (priv->post_irq) priv->post_irq(priv); if (n >= SJA1000_MAX_IRQ) netdev_dbg(dev, "%d messages handled in ISR", n); - return (n) ? IRQ_HANDLED : IRQ_NONE; + return ret; } EXPORT_SYMBOL_GPL(sja1000_interrupt); -- 2.40.1
