diff options
| author | Wolfram Sang <wsa+renesas@sang-engineering.com> | 2019-08-08 22:39:10 +0300 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2019-08-14 15:49:36 +0300 |
| commit | 7b814d852af6944657c2961039f404c4490771c0 (patch) | |
| tree | d9c018472072e09d33fc9a0e7de6a46211b4e2da | |
| parent | 8fc3ae3b109d17157102f0abf9c8fb1e16bf810a (diff) | |
| download | linux-7b814d852af6944657c2961039f404c4490771c0.tar.xz | |
i2c: rcar: avoid race when unregistering slave client
After we disabled interrupts, there might still be an active one
running. Sync before clearing the pointer to the slave device.
Fixes: de20d1857dd6 ("i2c: rcar: add slave support")
Reported-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| -rw-r--r-- | drivers/i2c/busses/i2c-rcar.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index d39a4606f72d..531c01100b56 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -139,6 +139,7 @@ struct rcar_i2c_priv { enum dma_data_direction dma_direction; struct reset_control *rstc; + int irq; }; #define rcar_i2c_priv_to_dev(p) ((p)->adap.dev.parent) @@ -861,9 +862,11 @@ static int rcar_unreg_slave(struct i2c_client *slave) WARN_ON(!priv->slave); + /* disable irqs and ensure none is running before clearing ptr */ rcar_i2c_write(priv, ICSIER, 0); rcar_i2c_write(priv, ICSCR, 0); + synchronize_irq(priv->irq); priv->slave = NULL; pm_runtime_put(rcar_i2c_priv_to_dev(priv)); @@ -918,7 +921,7 @@ static int rcar_i2c_probe(struct platform_device *pdev) struct i2c_adapter *adap; struct device *dev = &pdev->dev; struct i2c_timings i2c_t; - int irq, ret; + int ret; /* Otherwise logic will break because some bytes must always use PIO */ BUILD_BUG_ON_MSG(RCAR_MIN_DMA_LEN < 3, "Invalid min DMA length"); @@ -984,10 +987,10 @@ static int rcar_i2c_probe(struct platform_device *pdev) pm_runtime_put(dev); - irq = platform_get_irq(pdev, 0); - ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0, dev_name(dev), priv); + priv->irq = platform_get_irq(pdev, 0); + ret = devm_request_irq(dev, priv->irq, rcar_i2c_irq, 0, dev_name(dev), priv); if (ret < 0) { - dev_err(dev, "cannot get irq %d\n", irq); + dev_err(dev, "cannot get irq %d\n", priv->irq); goto out_pm_disable; } |