From f7eeb1af8537b05953fb1c88ab8b59d94059a381 Mon Sep 17 00:00:00 2001 From: Shengzhuo Wei Date: Thu, 27 Aug 2026 23:43:01 +0800 Subject: [PATCH] i2c: at91: release DMA channels on remove and probe error at91_twi_configure_dma() requests exclusive tx/rx DMA channels, but nothing ever releases them on driver detach, and the probe error path after the channels are acquired (i2c_add_numbered_adapter() failure) returns without releasing them either, because the remove callback is not invoked after a failed probe. Move the release into a helper, call it from the existing configure-failure path, the adapter-registration failure path, and at91_twi_remove(). Fixes: 60937b2cdbf9 ("i2c: at91: add dma support") Assisted-by: GLM:5.3 Signed-off-by: Shengzhuo Wei Cc: # v3.8+ Acked-by: Mukesh Kumar Savaliya Signed-off-by: Andi Shyti Link: https://patch.msgid.link/20260827-i2c-dma-channel-leak-v1-1-271d4adc03a0@cherr.cc --- drivers/i2c/busses/i2c-at91-core.c | 3 +++ drivers/i2c/busses/i2c-at91-master.c | 12 +++++++++++- drivers/i2c/busses/i2c-at91.h | 1 + 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c index b64adef778d4..8ca4556d9664 100644 --- a/drivers/i2c/busses/i2c-at91-core.c +++ b/drivers/i2c/busses/i2c-at91-core.c @@ -255,6 +255,7 @@ static int at91_twi_probe(struct platform_device *pdev) if (rc) { pm_runtime_disable(dev->dev); pm_runtime_set_suspended(dev->dev); + at91_twi_dma_release(dev); return rc; } @@ -270,6 +271,8 @@ static void at91_twi_remove(struct platform_device *pdev) i2c_del_adapter(&dev->adapter); + at91_twi_dma_release(dev); + pm_runtime_disable(dev->dev); pm_runtime_set_suspended(dev->dev); } diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c index 894cedbca99f..68238cc8aee0 100644 --- a/drivers/i2c/busses/i2c-at91-master.c +++ b/drivers/i2c/busses/i2c-at91-master.c @@ -817,11 +817,21 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) error: if (ret != -EPROBE_DEFER) dev_info(dev->dev, "can't get DMA channel, continue without DMA support\n"); + at91_twi_dma_release(dev); + return ret; +} + +void at91_twi_dma_release(struct at91_twi_dev *dev) +{ + struct at91_twi_dma *dma = &dev->dma; + if (dma->chan_rx) dma_release_channel(dma->chan_rx); if (dma->chan_tx) dma_release_channel(dma->chan_tx); - return ret; + dma->chan_rx = NULL; + dma->chan_tx = NULL; + dev->use_dma = false; } static int at91_init_twi_recovery_gpio(struct platform_device *pdev, diff --git a/drivers/i2c/busses/i2c-at91.h b/drivers/i2c/busses/i2c-at91.h index 942e9c3973bb..d68fcbbc3e0f 100644 --- a/drivers/i2c/busses/i2c-at91.h +++ b/drivers/i2c/busses/i2c-at91.h @@ -172,6 +172,7 @@ void at91_twi_irq_restore(struct at91_twi_dev *dev); void at91_init_twi_bus(struct at91_twi_dev *dev); void at91_init_twi_bus_master(struct at91_twi_dev *dev); +void at91_twi_dma_release(struct at91_twi_dev *dev); int at91_twi_probe_master(struct platform_device *pdev, u32 phy_addr, struct at91_twi_dev *dev);