2016-10-21 08:55:48

by Peter Griffin

Subject: [PATCH] [media] c8sectpfe: Remove clk_disable_unprepare hacks

Now that CLK_PROC_STFE is defined as a critical clock in
DT, we can remove the commented clk_disable_unprepare from
the c8sectpfe driver. This means we now have balanced
clk*enable/disable calls in the driver, but on STiH407
family the clock in reality will never actually be disabled.

This is due to a HW bug where once the IP has been configured
and the SLIM core is running, disabling the clock causes a
unrecoverable bus lockup.

Signed-off-by: Peter Griffin <[email protected]>
---
drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c b/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c
index 30c148b..79d793b 100644
--- a/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c
+++ b/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c
@@ -888,8 +888,7 @@ static int c8sectpfe_probe(struct platform_device *pdev)
return 0;

err_clk_disable:
- /* TODO uncomment when upstream has taken a reference on this clk */
- /*clk_disable_unprepare(fei->c8sectpfeclk);*/
+ clk_disable_unprepare(fei->c8sectpfeclk);
return ret;
}

@@ -924,11 +923,8 @@ static int c8sectpfe_remove(struct platform_device *pdev)
if (readl(fei->io + SYS_OTHER_CLKEN))
writel(0, fei->io + SYS_OTHER_CLKEN);

- /* TODO uncomment when upstream has taken a reference on this clk */
- /*
if (fei->c8sectpfeclk)
clk_disable_unprepare(fei->c8sectpfeclk);
- */

return 0;
}
--
1.9.1

2016-10-21 12:24:24

by Patrice CHOTARD

Subject: Re: [PATCH] [media] c8sectpfe: Remove clk_disable_unprepare hacks

On 10/21/2016 10:55 AM, Peter Griffin wrote:
> Now that CLK_PROC_STFE is defined as a critical clock in
> DT, we can remove the commented clk_disable_unprepare from
> the c8sectpfe driver. This means we now have balanced
> clk*enable/disable calls in the driver, but on STiH407
> family the clock in reality will never actually be disabled.
>
> This is due to a HW bug where once the IP has been configured
> and the SLIM core is running, disabling the clock causes a
> unrecoverable bus lockup.
>
> Signed-off-by: Peter Griffin <[email protected]>
> ---
> drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c b/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c
> index 30c148b..79d793b 100644
> --- a/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c
> +++ b/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c
> @@ -888,8 +888,7 @@ static int c8sectpfe_probe(struct platform_device *pdev)
> return 0;
>
> err_clk_disable:
> - /* TODO uncomment when upstream has taken a reference on this clk */
> - /*clk_disable_unprepare(fei->c8sectpfeclk);*/
> + clk_disable_unprepare(fei->c8sectpfeclk);
> return ret;
> }
>
> @@ -924,11 +923,8 @@ static int c8sectpfe_remove(struct platform_device *pdev)
> if (readl(fei->io + SYS_OTHER_CLKEN))
> writel(0, fei->io + SYS_OTHER_CLKEN);
>
> - /* TODO uncomment when upstream has taken a reference on this clk */
> - /*
> if (fei->c8sectpfeclk)
> clk_disable_unprepare(fei->c8sectpfeclk);
> - */
>
> return 0;
> }
>

Acked-by: Patrice Chotard <[email protected]>