| Message ID | 1349703336-8105-1-git-send-email-fabio.estevam@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
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 <fabio.estevam@freescale.com> > --- > 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
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 <fabio.estevam@freescale.com> > --- > 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
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)
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 <fabio.estevam@freescale.com> --- drivers/video/imxfb.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-)