On Thu, Oct 12, 2017 at 04:09:59PM -0700, Nicolin Chen wrote:
> Both tegra124-dfll and clk-dfll are using platform_set_drvdata
> to set drvdata of the exact same pdev while they use different
> pointers for the drvdata. Once the drvdata has been overwritten
> by tegra124-dfll, clk-dfll will never get its td pointer as it
> expects.
>
> Since tegra124-dfll merely needs its soc pointer in its remove
> function, this patch fixes the bug by removing the overwriting
> in the tegra124-dfll file and letting the tegra_dfll_unregister
> return an soc pointer for it.
>
> Signed-off-by: Nicolin Chen <nicoleots...@gmail.com>
Acked-By: Peter De Schrijver <pdeschrij...@nvidia.com>
> ---
>
> As I don't have a T124 platform, I can't verify it on a board.
> If someone could provide a Tested-by, it would be very helpful.
> The test could be a simple system suspend/resume that activates
> runtime_suspend/resume() where a platform_get_drvdata() would
> be called. -- Nicolin
>
> drivers/clk/tegra/clk-dfll.c | 10 +++++-----
> drivers/clk/tegra/clk-dfll.h | 2 +-
> drivers/clk/tegra/clk-tegra124-dfll-fcpu.c | 12 +++++-------
> 3 files changed, 11 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/clk/tegra/clk-dfll.c b/drivers/clk/tegra/clk-dfll.c
> index 2c44aeb..0a7deee 100644
> --- a/drivers/clk/tegra/clk-dfll.c
> +++ b/drivers/clk/tegra/clk-dfll.c
> @@ -1728,10 +1728,10 @@ EXPORT_SYMBOL(tegra_dfll_register);
> * @pdev: DFLL platform_device *
> *
> * Unbind this driver from the DFLL hardware device represented by
> - * @pdev. The DFLL must be disabled for this to succeed. Returns 0
> - * upon success or -EBUSY if the DFLL is still active.
> + * @pdev. The DFLL must be disabled for this to succeed. Returns a
> + * soc pointer upon success or -EBUSY if the DFLL is still active.
> */
> -int tegra_dfll_unregister(struct platform_device *pdev)
> +struct tegra_dfll_soc_data *tegra_dfll_unregister(struct platform_device
> *pdev)
> {
> struct tegra_dfll *td = platform_get_drvdata(pdev);
>
> @@ -1739,7 +1739,7 @@ int tegra_dfll_unregister(struct platform_device *pdev)
> if (td->mode != DFLL_DISABLED) {
> dev_err(&pdev->dev,
> "must disable DFLL before removing driver\n");
> - return -EBUSY;
> + return ERR_PTR(-EBUSY);
> }
>
> debugfs_remove_recursive(td->debugfs_dir);
> @@ -1753,6 +1753,6 @@ int tegra_dfll_unregister(struct platform_device *pdev)
>
> reset_control_assert(td->dvco_rst);
>
> - return 0;
> + return td->soc;
> }
> EXPORT_SYMBOL(tegra_dfll_unregister);
> diff --git a/drivers/clk/tegra/clk-dfll.h b/drivers/clk/tegra/clk-dfll.h
> index ed2ad88..83352c8 100644
> --- a/drivers/clk/tegra/clk-dfll.h
> +++ b/drivers/clk/tegra/clk-dfll.h
> @@ -43,7 +43,7 @@ struct tegra_dfll_soc_data {
>
> int tegra_dfll_register(struct platform_device *pdev,
> struct tegra_dfll_soc_data *soc);
> -int tegra_dfll_unregister(struct platform_device *pdev);
> +struct tegra_dfll_soc_data *tegra_dfll_unregister(struct platform_device
> *pdev);
> int tegra_dfll_runtime_suspend(struct device *dev);
> int tegra_dfll_runtime_resume(struct device *dev);
>
> diff --git a/drivers/clk/tegra/clk-tegra124-dfll-fcpu.c
> b/drivers/clk/tegra/clk-tegra124-dfll-fcpu.c
> index ad1c1cc..269d359 100644
> --- a/drivers/clk/tegra/clk-tegra124-dfll-fcpu.c
> +++ b/drivers/clk/tegra/clk-tegra124-dfll-fcpu.c
> @@ -125,19 +125,17 @@ static int tegra124_dfll_fcpu_probe(struct
> platform_device *pdev)
> return err;
> }
>
> - platform_set_drvdata(pdev, soc);
> -
> return 0;
> }
>
> static int tegra124_dfll_fcpu_remove(struct platform_device *pdev)
> {
> - struct tegra_dfll_soc_data *soc = platform_get_drvdata(pdev);
> - int err;
> + struct tegra_dfll_soc_data *soc;
>
> - err = tegra_dfll_unregister(pdev);
> - if (err < 0)
> - dev_err(&pdev->dev, "failed to unregister DFLL: %d\n", err);
> + soc = tegra_dfll_unregister(pdev);
> + if (IS_ERR(soc))
> + dev_err(&pdev->dev, "failed to unregister DFLL: %ld\n",
> + PTR_ERR(soc));
>
> tegra_cvb_remove_opp_table(soc->dev, soc->cvb, soc->max_freq);
>
> --
> 2.1.4
>
> --
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