diff options
| author | Fabio Estevam <fabio.estevam@freescale.com> | 2013-01-16 16:58:41 +0400 |
|---|---|---|
| committer | Shawn Guo <shawn.guo@linaro.org> | 2013-01-17 12:14:29 +0400 |
| commit | e6b267ce14f61d9da0151b97ee26ab4d38055567 (patch) | |
| tree | 3be89be02a17a929c96187d66098e8163a8121a8 /drivers/video/imxfb.c | |
| parent | 83ae20981ae924c37d02a42c829155fc3851260c (diff) | |
| download | linux-e6b267ce14f61d9da0151b97ee26ab4d38055567.tar.xz | |
video: imxfb: Do not crash on reboot
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.
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Diffstat (limited to 'drivers/video/imxfb.c')
| -rw-r--r-- | drivers/video/imxfb.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c index 8435c5d601a1..609f4e97bde7 100644 --- a/drivers/video/imxfb.c +++ b/drivers/video/imxfb.c @@ -139,6 +139,7 @@ struct imxfb_info { struct clk *clk_ahb; struct clk *clk_per; enum imxfb_type devtype; + bool enabled; /* * These are the addresses we mapped @@ -536,6 +537,10 @@ static void imxfb_exit_backlight(struct imxfb_info *fbi) static void imxfb_enable_controller(struct imxfb_info *fbi) { + + if (fbi->enabled) + return; + pr_debug("Enabling LCD controller\n"); writel(fbi->screen_dma, fbi->regs + LCDC_SSA); @@ -556,6 +561,7 @@ static void imxfb_enable_controller(struct imxfb_info *fbi) clk_prepare_enable(fbi->clk_ipg); clk_prepare_enable(fbi->clk_ahb); clk_prepare_enable(fbi->clk_per); + fbi->enabled = true; if (fbi->backlight_power) fbi->backlight_power(1); @@ -565,6 +571,9 @@ static void imxfb_enable_controller(struct imxfb_info *fbi) static void imxfb_disable_controller(struct imxfb_info *fbi) { + if (!fbi->enabled) + return; + pr_debug("Disabling LCD controller\n"); if (fbi->backlight_power) @@ -575,6 +584,7 @@ static void imxfb_disable_controller(struct imxfb_info *fbi) clk_disable_unprepare(fbi->clk_per); clk_disable_unprepare(fbi->clk_ipg); clk_disable_unprepare(fbi->clk_ahb); + fbi->enabled = false; writel(0, fbi->regs + LCDC_RMCR); } |