From 62e7aa59a616c370a3a614d735805e969caf771a Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Tue, 14 Nov 2017 11:03:22 +0000 Subject: [PATCH] mcp2515: Use DT-supplied interrupt flags The MCP2515 datasheet clearly describes a level-triggered interrupt pin. Therefore the receiving interrupt controller must also be configured for level-triggered operation otherwise there is a danger of a missed interrupt condition blocking all subsequent interrupts. The ONESHOT flag ensures that the interrupt is masked until the threaded interrupt handler exits. Rather than change the flags globally (they must have worked for at least one user), allow the flags to be overridden from Device Tree in the event that the device has a DT node. See: https://github.com/raspberrypi/linux/issues/2175 https://github.com/raspberrypi/linux/issues/2263 Signed-off-by: Phil Elwell --- drivers/net/can/spi/mcp251x.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c index e908176086450..663203fbb1b83 100644 --- a/drivers/net/can/spi/mcp251x.c +++ b/drivers/net/can/spi/mcp251x.c @@ -951,6 +951,9 @@ static int mcp251x_open(struct net_device *net) priv->tx_skb = NULL; priv->tx_len = 0; + if (spi->dev.of_node) + flags = 0; + ret = request_threaded_irq(spi->irq, NULL, mcp251x_can_ist, flags | IRQF_ONESHOT, DEVICE_NAME, priv); if (ret) {