Issuing a "reboot" command after the LCD times out causes the following
warnings:
Requesting system reboot
------------[ cut here ]------------
WARNING: at drivers/clk/clk.c:471 clk_disable+0x24/0x50()
Modules linked in:
[<c001ad90>] (unwind_backtrace+0x0/0xf4) from [<c0025aac>] (warn_slowpath_common+0x48/0x60)
[<c0025aac>] (warn_slowpath_common+0x48/0x60) from [<c0025ae0>] (warn_slowpath_null+0x1c/0x24)
[<c0025ae0>] (warn_slowpath_null+0x1c/0x24) from [<c03960a0>] (clk_disable+0x24/0x50)
[<c03960a0>] (clk_disable+0x24/0x50) from [<c02695a0>] (imxfb_disable_controller+0x48/0x7c)
[<c02695a0>] (imxfb_disable_controller+0x48/0x7c) from [<c029d838>] (platform_drv_shutdown+0x18/0x1c)
[<c029d838>] (platform_drv_shutdown+0x18/0x1c) from [<c02990fc>] (device_shutdown+0x48/0x14c)
[<c02990fc>] (device_shutdown+0x48/0x14c) from [<c003d09c>] (kernel_restart_prepare+0x2c/0x3c)
[<c003d09c>] (kernel_restart_prepare+0x2c/0x3c) from [<c003d0e4>] (kernel_restart+0xc/0x48)
[<c003d0e4>] (kernel_restart+0xc/0x48) from [<c003d1e8>] (sys_reboot+0xc0/0x1bc)
[<c003d1e8>] (sys_reboot+0xc0/0x1bc) from [<c0014ca0>] (ret_fast_syscall+0x0/0x2c)
---[ end trace da6b502ca79c854f ]---
------------[ cut here ]------------
WARNING: at drivers/clk/clk.c:380 clk_unprepare+0x1c/0x2c()
Modules linked in:
[<c001ad90>] (unwind_backtrace+0x0/0xf4) from [<c0025aac>] (warn_slowpath_common+0x48/0x60)
[<c0025aac>] (warn_slowpath_common+0x48/0x60) from [<c0025ae0>] (warn_slowpath_null+0x1c/0x24)
[<c0025ae0>] (warn_slowpath_null+0x1c/0x24) from [<c0396338>] (clk_unprepare+0x1c/0x2c)
[<c0396338>] (clk_unprepare+0x1c/0x2c) from [<c02695a8>] (imxfb_disable_controller+0x50/0x7c)
[<c02695a8>] (imxfb_disable_controller+0x50/0x7c) from [<c029d838>] (platform_drv_shutdown+0x18/0x1c)
[<c029d838>] (platform_drv_shutdown+0x18/0x1c) from [<c02990fc>] (device_shutdown+0x48/0x14c)
[<c02990fc>] (device_shutdown+0x48/0x14c) from [<c003d09c>] (kernel_restart_prepare+0x2c/0x3c)
[<c003d09c>] (kernel_restart_prepare+0x2c/0x3c) from [<c003d0e4>] (kernel_restart+0xc/0x48)
[<c003d0e4>] (kernel_restart+0xc/0x48) from [<c003d1e8>] (sys_reboot+0xc0/0x1bc)
[<c003d1e8>] (sys_reboot+0xc0/0x1bc) from [<c0014ca0>] (ret_fast_syscall+0x0/0x2c)
---[ end trace da6b502ca79c8550 ]---
------------[ cut here ]------------
This happens because "reboot" triggers imxfb_shutdown(), which calls
imxfb_disable_controller with the clocks already disabled.
To prevent this, add a clock enabled status so that we can check if the clocks
are enabled before disabling them.
Signed-off-by: Fabio Estevam <[email protected]>
---
drivers/video/imxfb.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
index f3363b2..6acf98a 100644
--- a/drivers/video/imxfb.c
+++ b/drivers/video/imxfb.c
@@ -134,6 +134,7 @@ struct imxfb_info {
struct clk *clk_ipg;
struct clk *clk_ahb;
struct clk *clk_per;
+ int enabled;
/*
* These are the addresses we mapped
@@ -530,9 +531,12 @@ static void imxfb_enable_controller(struct imxfb_info *fbi)
*/
writel(RMCR_LCDC_EN_MX1, fbi->regs + LCDC_RMCR);
- clk_prepare_enable(fbi->clk_ipg);
- clk_prepare_enable(fbi->clk_ahb);
- clk_prepare_enable(fbi->clk_per);
+ if (!fbi->enabled) {
+ clk_prepare_enable(fbi->clk_ipg);
+ clk_prepare_enable(fbi->clk_ahb);
+ clk_prepare_enable(fbi->clk_per);
+ fbi->enabled = 1;
+ }
if (fbi->backlight_power)
fbi->backlight_power(1);
@@ -551,9 +555,12 @@ static void imxfb_disable_controller(struct imxfb_info *fbi)
writel(0, fbi->regs + LCDC_RMCR);
- clk_disable_unprepare(fbi->clk_per);
- clk_disable_unprepare(fbi->clk_ipg);
- clk_disable_unprepare(fbi->clk_ahb);
+ if (fbi->enabled) {
+ clk_disable_unprepare(fbi->clk_per);
+ clk_disable_unprepare(fbi->clk_ipg);
+ clk_disable_unprepare(fbi->clk_ahb);
+ fbi->enabled = 0;
+ }
}
static int imxfb_blank(int blank, struct fb_info *info)
--
1.7.9.5
On Mon, Oct 08, 2012 at 10:35:36AM -0300, Fabio Estevam wrote:
> Issuing a "reboot" command after the LCD times out causes the following
> warnings:
>
> Requesting system reboot
[...]
>
> This happens because "reboot" triggers imxfb_shutdown(), which calls
> imxfb_disable_controller with the clocks already disabled.
>
> To prevent this, add a clock enabled status so that we can check if the clocks
> are enabled before disabling them.
>
> Signed-off-by: Fabio Estevam <[email protected]>
> ---
> drivers/video/imxfb.c | 19 +++++++++++++------
> 1 file changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
> index f3363b2..6acf98a 100644
> --- a/drivers/video/imxfb.c
> +++ b/drivers/video/imxfb.c
> @@ -134,6 +134,7 @@ struct imxfb_info {
> struct clk *clk_ipg;
> struct clk *clk_ahb;
> struct clk *clk_per;
> + int enabled;
>
> /*
> * These are the addresses we mapped
> @@ -530,9 +531,12 @@ static void imxfb_enable_controller(struct imxfb_info *fbi)
> */
> writel(RMCR_LCDC_EN_MX1, fbi->regs + LCDC_RMCR);
>
> - clk_prepare_enable(fbi->clk_ipg);
> - clk_prepare_enable(fbi->clk_ahb);
> - clk_prepare_enable(fbi->clk_per);
> + if (!fbi->enabled) {
> + clk_prepare_enable(fbi->clk_ipg);
> + clk_prepare_enable(fbi->clk_ahb);
> + clk_prepare_enable(fbi->clk_per);
> + fbi->enabled = 1;
> + }
>
> if (fbi->backlight_power)
> fbi->backlight_power(1);
> @@ -551,9 +555,12 @@ static void imxfb_disable_controller(struct imxfb_info *fbi)
>
> writel(0, fbi->regs + LCDC_RMCR);
>
> - clk_disable_unprepare(fbi->clk_per);
> - clk_disable_unprepare(fbi->clk_ipg);
> - clk_disable_unprepare(fbi->clk_ahb);
> + if (fbi->enabled) {
> + clk_disable_unprepare(fbi->clk_per);
> + clk_disable_unprepare(fbi->clk_ipg);
> + clk_disable_unprepare(fbi->clk_ahb);
> + fbi->enabled = 0;
> + }
I think the complete functions should be protected, not only the clocks.
Sascha
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
On Mon, Oct 08, 2012 at 10:35:36AM -0300, Fabio Estevam wrote:
> Issuing a "reboot" command after the LCD times out causes the following
> warnings:
>
> Requesting system reboot
> ------------[ cut here ]------------
> WARNING: at drivers/clk/clk.c:471 clk_disable+0x24/0x50()
> Modules linked in:
> [<c001ad90>] (unwind_backtrace+0x0/0xf4) from [<c0025aac>] (warn_slowpath_common+0x48/0x60)
> [<c0025aac>] (warn_slowpath_common+0x48/0x60) from [<c0025ae0>] (warn_slowpath_null+0x1c/0x24)
> [<c0025ae0>] (warn_slowpath_null+0x1c/0x24) from [<c03960a0>] (clk_disable+0x24/0x50)
> [<c03960a0>] (clk_disable+0x24/0x50) from [<c02695a0>] (imxfb_disable_controller+0x48/0x7c)
> [<c02695a0>] (imxfb_disable_controller+0x48/0x7c) from [<c029d838>] (platform_drv_shutdown+0x18/0x1c)
> [<c029d838>] (platform_drv_shutdown+0x18/0x1c) from [<c02990fc>] (device_shutdown+0x48/0x14c)
> [<c02990fc>] (device_shutdown+0x48/0x14c) from [<c003d09c>] (kernel_restart_prepare+0x2c/0x3c)
> [<c003d09c>] (kernel_restart_prepare+0x2c/0x3c) from [<c003d0e4>] (kernel_restart+0xc/0x48)
> [<c003d0e4>] (kernel_restart+0xc/0x48) from [<c003d1e8>] (sys_reboot+0xc0/0x1bc)
> [<c003d1e8>] (sys_reboot+0xc0/0x1bc) from [<c0014ca0>] (ret_fast_syscall+0x0/0x2c)
> ---[ end trace da6b502ca79c854f ]---
> ------------[ cut here ]------------
> WARNING: at drivers/clk/clk.c:380 clk_unprepare+0x1c/0x2c()
> Modules linked in:
> [<c001ad90>] (unwind_backtrace+0x0/0xf4) from [<c0025aac>] (warn_slowpath_common+0x48/0x60)
> [<c0025aac>] (warn_slowpath_common+0x48/0x60) from [<c0025ae0>] (warn_slowpath_null+0x1c/0x24)
> [<c0025ae0>] (warn_slowpath_null+0x1c/0x24) from [<c0396338>] (clk_unprepare+0x1c/0x2c)
> [<c0396338>] (clk_unprepare+0x1c/0x2c) from [<c02695a8>] (imxfb_disable_controller+0x50/0x7c)
> [<c02695a8>] (imxfb_disable_controller+0x50/0x7c) from [<c029d838>] (platform_drv_shutdown+0x18/0x1c)
> [<c029d838>] (platform_drv_shutdown+0x18/0x1c) from [<c02990fc>] (device_shutdown+0x48/0x14c)
> [<c02990fc>] (device_shutdown+0x48/0x14c) from [<c003d09c>] (kernel_restart_prepare+0x2c/0x3c)
> [<c003d09c>] (kernel_restart_prepare+0x2c/0x3c) from [<c003d0e4>] (kernel_restart+0xc/0x48)
> [<c003d0e4>] (kernel_restart+0xc/0x48) from [<c003d1e8>] (sys_reboot+0xc0/0x1bc)
> [<c003d1e8>] (sys_reboot+0xc0/0x1bc) from [<c0014ca0>] (ret_fast_syscall+0x0/0x2c)
> ---[ end trace da6b502ca79c8550 ]---
> ------------[ cut here ]------------
>
> This happens because "reboot" triggers imxfb_shutdown(), which calls
> imxfb_disable_controller with the clocks already disabled.
>
> To prevent this, add a clock enabled status so that we can check if the clocks
> are enabled before disabling them.
>
> Signed-off-by: Fabio Estevam <[email protected]>
> ---
> drivers/video/imxfb.c | 19 +++++++++++++------
> 1 file changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
> index f3363b2..6acf98a 100644
> --- a/drivers/video/imxfb.c
> +++ b/drivers/video/imxfb.c
> @@ -134,6 +134,7 @@ struct imxfb_info {
> struct clk *clk_ipg;
> struct clk *clk_ahb;
> struct clk *clk_per;
> + int enabled;
I didn't really know the driver, but I wonder if the name "enabled" is a
tad too generic. Maybe better "clks_enabled"?
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |