[PATCH] media: imx-jpeg: Ensure power suppliers be suspended before detach them

[Ming Qian]

The power suppliers are always requested to suspend asynchronously,
dev_pm_domain_detach() requires the caller to ensure proper
synchronization of this function with power management callbacks.
otherwise the detach may led to kernel panic, like below:

[ 1457.107934] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000040
[ 1457.116777] Mem abort info:
[ 1457.119589]   ESR = 0x0000000096000004
[ 1457.123358]   EC = 0x25: DABT (current EL), IL = 32 bits
[ 1457.128692]   SET = 0, FnV = 0
[ 1457.131764]   EA = 0, S1PTW = 0
[ 1457.134920]   FSC = 0x04: level 0 translation fault
[ 1457.139812] Data abort info:
[ 1457.142707]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[ 1457.148196]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[ 1457.153256]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[ 1457.158563] user pgtable: 4k pages, 48-bit VAs, pgdp=00000001138b6000
[ 1457.165000] [0000000000000040] pgd=0000000000000000, p4d=0000000000000000
[ 1457.171792] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[ 1457.178045] Modules linked in: v4l2_jpeg wave6_vpu_ctrl(-) [last unloaded: mxc_jpeg_encdec]
[ 1457.186383] CPU: 0 PID: 51938 Comm: kworker/0:3 Not tainted 6.6.36-gd23d64eea511 #66
[ 1457.194112] Hardware name: NXP i.MX95 19X19 board (DT)
[ 1457.199236] Workqueue: pm pm_runtime_work
[ 1457.203247] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 1457.210188] pc : genpd_runtime_suspend+0x20/0x290
[ 1457.214886] lr : __rpm_callback+0x48/0x1d8
[ 1457.218968] sp : ffff80008250bc50
[ 1457.222270] x29: ffff80008250bc50 x28: 0000000000000000 x27: 0000000000000000
[ 1457.229394] x26: 0000000000000000 x25: 0000000000000008 x24: 00000000000f4240
[ 1457.236518] x23: 0000000000000000 x22: ffff00008590f0e4 x21: 0000000000000008
[ 1457.243642] x20: ffff80008099c434 x19: ffff00008590f000 x18: ffffffffffffffff
[ 1457.250766] x17: 5300326563697665 x16: 645f676e696c6f6f x15: 63343a6d726f6674
[ 1457.257890] x14: 0000000000000004 x13: 00000000000003a4 x12: 0000000000000002
[ 1457.265014] x11: 0000000000000000 x10: 0000000000000a60 x9 : ffff80008250bbb0
[ 1457.272138] x8 : ffff000092937200 x7 : ffff0003fdf6af80 x6 : 0000000000000000
[ 1457.279262] x5 : 00000000410fd050 x4 : 0000000000200000 x3 : 0000000000000000
[ 1457.286386] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff00008590f000
[ 1457.293510] Call trace:
[ 1457.295946]  genpd_runtime_suspend+0x20/0x290
[ 1457.300296]  __rpm_callback+0x48/0x1d8
[ 1457.304038]  rpm_callback+0x6c/0x78
[ 1457.307515]  rpm_suspend+0x10c/0x570
[ 1457.311077]  pm_runtime_work+0xc4/0xc8
[ 1457.314813]  process_one_work+0x138/0x248
[ 1457.318816]  worker_thread+0x320/0x438
[ 1457.322552]  kthread+0x110/0x114
[ 1457.325767]  ret_from_fork+0x10/0x20

Fixes: 2db16c6ed72c ("media: imx-jpeg: Add V4L2 driver for i.MX8 JPEG Encoder/Decoder")
Signed-off-by: Ming Qian <ming.qian@xxxxxxx>
Reviewed-by: TaoJiang <tao.jiang_2@xxxxxxx>
---
 drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
index 979b03b112f8..1bf85c1cf964 100644
--- a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
+++ b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
@@ -2679,6 +2679,8 @@ static void mxc_jpeg_detach_pm_domains(struct mxc_jpeg_dev *jpeg)
 	int i;
 
 	for (i = 0; i < jpeg->num_domains; i++) {
+		if (jpeg->pd_dev[i] && !pm_runtime_suspended(jpeg->pd_dev[i]))
+			pm_runtime_force_suspend(jpeg->pd_dev[i]);
 		if (jpeg->pd_link[i] && !IS_ERR(jpeg->pd_link[i]))
 			device_link_del(jpeg->pd_link[i]);
 		if (jpeg->pd_dev[i] && !IS_ERR(jpeg->pd_dev[i]))
-- 
2.43.0-rc1