[PATCH] i2c: mxs: fix DMA channel leak on probe error
Ruoyu Wang <[email protected]>
| Newsgroups | dev.linux.lists.imx,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-i2c,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
dma_request_chan() grants the driver exclusive use of the channel until
dma_release_channel() is called. If controller reset or I2C adapter
registration fails after the request, mxs_i2c_probe() returns without
releasing it. The failed probe does not invoke mxs_i2c_remove(), so the
channel remains allocated and can prevent a later probe from acquiring
it.
Release the DMA channel on both post-request error paths. Keep the
adapter-registration unwind ordered after the existing controller reset.
This issue was found by a static analysis checker and confirmed by
manual source review.
Fixes: 62885f59a261 ("MXS: Implement DMA support into mxs-i2c")
Signed-off-by: Ruoyu Wang <[email protected]>
---
drivers/i2c/busses/i2c-mxs.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
index 4e07babea9c3f..a5c8b44ec8142 100644
--- a/drivers/i2c/busses/i2c-mxs.c
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -849,8 +849,10 @@ static int mxs_i2c_probe(struct platform_device *pdev)
/* Do reset to enforce correct startup after pinmuxing */
err = mxs_i2c_reset(i2c);
- if (err)
+ if (err) {
+ dma_release_channel(i2c->dmach);
return err;
+ }
adap = &i2c->adapter;
strscpy(adap->name, "MXS I2C adapter", sizeof(adap->name));
@@ -865,6 +867,7 @@ static int mxs_i2c_probe(struct platform_device *pdev)
if (err) {
writel(MXS_I2C_CTRL0_SFTRST,
i2c->regs + MXS_I2C_CTRL0_SET);
+ dma_release_channel(i2c->dmach);
return err;
}
--
2.51.0