On 25/03/2019 15:30, [email protected] wrote: > From: Laurentiu Tudor <[email protected]> > > If the dma controller is not yet probed, defer i2c probe. > The error path in probe was slightly modified (no functional change)
There is a functional change for cases like: > ret = pm_runtime_get_sync(&pdev->dev); > if (ret < 0) > goto rpm_disable; ...as rpm_disable will no longer fall through to the call of clk_disable_unprepare(). > to avoid triggering this WARN_ON(): > "cg-pll0-div1 already disabled > WARNING: CPU: 1 PID: 1 at drivers/clk/clk.c:828 clk_core_disable+0xa8/0xb0" I'm also not sure how this WARN_ON was hit. i2c_imx_probe() calls clk_prepare_enable() which should increment the reference count. So it should always be possible to decrememt the enable_count. What am I missing? > Signed-off-by: Laurentiu Tudor <[email protected]> > --- > drivers/i2c/busses/i2c-imx.c | 21 +++++++++++++-------- > 1 file changed, 13 insertions(+), 8 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c > index 42fed40198a0..4e34b1572756 100644 > --- a/drivers/i2c/busses/i2c-imx.c > +++ b/drivers/i2c/busses/i2c-imx.c > @@ -1111,7 +1111,8 @@ static int i2c_imx_probe(struct platform_device *pdev) > pdev->name, i2c_imx); > if (ret) { > dev_err(&pdev->dev, "can't claim irq %d\n", irq); > - goto clk_disable; > + clk_disable_unprepare(i2c_imx->clk); > + return ret; > } > > /* Init queue */ > @@ -1161,19 +1162,25 @@ static int i2c_imx_probe(struct platform_device *pdev) > pm_runtime_mark_last_busy(&pdev->dev); > pm_runtime_put_autosuspend(&pdev->dev); > > + /* Init DMA config if supported */ > + ret = i2c_imx_dma_request(i2c_imx, phy_addr); > + if (ret) { > + if (ret != -EPROBE_DEFER) > + dev_info(&pdev->dev, "can't use DMA, using PIO > instead.\n"); > + else > + goto del_adapter; > + } > + This can be simplified by reversing the condition: if (ret) { if (ret == -EPROBE_DEFER) goto del_adapter; dev_info(); } or even: if (ret == -EPROBE_DEFER) goto del_adapter; else if (ret) dev_info(); > dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq); > dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res); > dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n", > i2c_imx->adapter.name); > > - /* Init DMA config if supported */ > - ret = i2c_imx_dma_request(i2c_imx, phy_addr); > - if (ret < 0) > - goto clk_notifier_unregister; > - > dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n"); > return 0; /* Return OK */ > > +del_adapter: > + i2c_del_adapter(&i2c_imx->adapter); This looks like a separate fix (previously the call to i2c_add_numbered_adapter() was not undone in case of later errors). It worth spelling this out in the commit message. Thanks, Steve > clk_notifier_unregister: > clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb); > rpm_disable: > @@ -1182,8 +1189,6 @@ static int i2c_imx_probe(struct platform_device *pdev) > pm_runtime_set_suspended(&pdev->dev); > pm_runtime_dont_use_autosuspend(&pdev->dev); > > -clk_disable: > - clk_disable_unprepare(i2c_imx->clk); > return ret; > } > >
