Re: [PATCH] soc/tegra: fuse: Add clock error check in tegra_fuse_readl

From: Jon Hunter
Date: Mon Sep 02 2019 - 06:45:07 EST



On 28/08/2019 12:18, Nagarjuna Kristam wrote:
> Tegra fuse clock handle is retrieved in tegra_fuse_probe().
> tegra_fuse_readl() is exported symbol, which can be called from drivers
> at any time. tegra_fuse_readl() enables fuse clock and reads corresponding
> fuse register offset.
>
> Calling tegra_fuse_readl() before tegra_fuse_probe(), will cause data
> abort. Add DEFER_PROBE error check for fuse clock in tegra_fuse_readl(),
> to avoid enabling of fuse clock, before clock is available.
>
> Signed-off-by: Nagarjuna Kristam <nkristam@xxxxxxxxxx>
> ---
> drivers/soc/tegra/fuse/fuse-tegra.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c
> index 3eb44e6..21b39b7 100644
> --- a/drivers/soc/tegra/fuse/fuse-tegra.c
> +++ b/drivers/soc/tegra/fuse/fuse-tegra.c
> @@ -186,7 +186,7 @@ u32 __init tegra_fuse_read_early(unsigned int offset)
>
> int tegra_fuse_readl(unsigned long offset, u32 *value)
> {
> - if (!fuse->read)
> + if (!fuse->read || (PTR_ERR(fuse->clk) == -EPROBE_DEFER))
> return -EPROBE_DEFER;

What about the case where fuse->clk is NULL or a different error value?

Jon

--
nvpublic