From: Hans de Goede Date: Mon, 16 Oct 2017 12:34:48 +0000 (+0200) Subject: media: staging: media: atomisp: Fix oops by unbalanced clk enable/disable call X-Git-Tag: v4.19~2007^2~172 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=1f709713cbd70efe85e76d9e9453606c6cc4bf82;p=platform%2Fkernel%2Flinux-rpi.git media: staging: media: atomisp: Fix oops by unbalanced clk enable/disable call The common-clk core expects clk consumers to always call enable/disable in a balanced manner. The atomisp driver does not call gmin_flisclk_ctrl() in a balanced manner, so add a clock_on bool and skip redundant calls. This fixes kernel oops like this one: [ 19.811613] gc0310_s_config S [ 19.811655] ------------[ cut here ]------------ [ 19.811664] WARNING: CPU: 1 PID: 720 at drivers/clk/clk.c:594 clk_core_disabl [ 19.811666] Modules linked in: tpm_crb(+) snd_soc_sst_atom_hifi2_platform tpm [ 19.811744] CPU: 1 PID: 720 Comm: systemd-udevd Tainted: G C OE 4.1 [ 19.811746] Hardware name: Insyde T701/T701, BIOS BYT70A.YNCHENG.WIN.007 08/2 [ 19.811749] task: ffff988df7ab2500 task.stack: ffffac1400474000 [ 19.811752] RIP: 0010:clk_core_disable+0xc0/0x130 ... [ 19.811775] Call Trace: [ 19.811783] clk_core_disable_lock+0x1f/0x30 [ 19.811788] clk_disable+0x1f/0x30 [ 19.811794] gmin_flisclk_ctrl+0x87/0xf0 [ 19.811801] 0xffffffffc0528512 [ 19.811805] 0xffffffffc05295e2 [ 19.811811] ? acpi_device_wakeup_disable+0x50/0x60 [ 19.811815] ? acpi_dev_pm_attach+0x8e/0xd0 [ 19.811818] ? 0xffffffffc05294d0 [ 19.811823] i2c_device_probe+0x1cd/0x280 [ 19.811828] driver_probe_device+0x2ff/0x450 Fixes: "staging: atomisp: use clock framework for camera clocks" Signed-off-by: Hans de Goede Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c b/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c index 17b4cfa..8a20a28 100644 --- a/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c +++ b/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c @@ -29,6 +29,7 @@ struct gmin_subdev { struct v4l2_subdev *subdev; int clock_num; int clock_src; + bool clock_on; struct clk *pmc_clk; struct gpio_desc *gpio0; struct gpio_desc *gpio1; @@ -572,6 +573,9 @@ static int gmin_flisclk_ctrl(struct v4l2_subdev *subdev, int on) struct gmin_subdev *gs = find_gmin_subdev(subdev); struct i2c_client *client = v4l2_get_subdevdata(subdev); + if (gs->clock_on == !!on) + return 0; + if (on) { ret = clk_set_rate(gs->pmc_clk, gs->clock_src); @@ -580,8 +584,11 @@ static int gmin_flisclk_ctrl(struct v4l2_subdev *subdev, int on) gs->clock_src); ret = clk_prepare_enable(gs->pmc_clk); + if (ret == 0) + gs->clock_on = true; } else { clk_disable_unprepare(gs->pmc_clk); + gs->clock_on = false; } return ret;