From: Wolfram Sang wsa+renesas@sang-engineering.com
[ Upstream commit 7b814d852af6944657c2961039f404c4490771c0 ]
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 Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i2c/busses/i2c-rcar.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 3415733a93645..132c4a405bf83 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -144,6 +144,7 @@ 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) @@ -813,9 +814,11 @@ 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)); @@ -866,7 +869,7 @@ 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;
priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL); if (!priv) @@ -927,10 +930,10 @@ 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; }