From 25b401c1816ae64bcc5dcb1d39ab41812522a0ce Mon Sep 17 00:00:00 2001 From: Stefan Agner Date: Mon, 18 May 2015 18:33:27 +0200 Subject: [PATCH] can: mcp251x: fix resume when device is down If a valid power regulator or a dummy regulator is used (which happens to be the case when no regulator is specified), restart_work is queued no matter whether the device was running or not at suspend time. Since work queues get initialized in the ndo_open callback, resuming leads to a NULL pointer exception. Reverse exactly the steps executed at suspend time: - Enable the power regulator in any case - Enable the transceiver regulator if the device was running, even in case we have a power regulator - Queue restart_work only in case the device was running Fixes: bf66f3736a94 ("can: mcp251x: Move to threaded interrupts instead of workqueues.") Signed-off-by: Stefan Agner Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- drivers/net/can/spi/mcp251x.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c index c1a95a34d62e..3b2f34e6ba9b 100644 --- a/drivers/net/can/spi/mcp251x.c +++ b/drivers/net/can/spi/mcp251x.c @@ -1222,17 +1222,16 @@ static int __maybe_unused mcp251x_can_resume(struct device *dev) struct spi_device *spi = to_spi_device(dev); struct mcp251x_priv *priv = spi_get_drvdata(spi); - if (priv->after_suspend & AFTER_SUSPEND_POWER) { + if (priv->after_suspend & AFTER_SUSPEND_POWER) mcp251x_power_enable(priv->power, 1); + + if (priv->after_suspend & AFTER_SUSPEND_UP) { + mcp251x_power_enable(priv->transceiver, 1); queue_work(priv->wq, &priv->restart_work); } else { - if (priv->after_suspend & AFTER_SUSPEND_UP) { - mcp251x_power_enable(priv->transceiver, 1); - queue_work(priv->wq, &priv->restart_work); - } else { - priv->after_suspend = 0; - } + priv->after_suspend = 0; } + priv->force_quit = 0; enable_irq(spi->irq); return 0; -- 2.20.1