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 <hdegoede@xxxxxxxxxx>
---
.../media/atomisp/platform/intel-mid/atomisp_gmin_platform.c | 7 +++++++
1 file changed, 7 insertions(+)
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 828fe5abd832..6671ebe4ecc9 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;
@@ -583,6 +584,9 @@ 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);
@@ -591,8 +595,11 @@ 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;
--
2.14.2
