spi: geni-qcom: Fix boot warning related to pm_runtime and devres

From: Georgi Djakov <[email protected]>

During boot, users sometimes observe the following warning:

[7.841431] WARNING: CPU: 4 PID: 492 at
drivers/interconnect/core.c:685 __icc_enable
(drivers/interconnect/core.c:685 (discriminator 7))
[..]
[7.841494] CPU: 4 PID: 492 Comm: (udev-worker) Not tainted 6.1.111-rc1 #1
[7.841497] Hardware name: Thundercomm Dragonboard 845c (DT)
[7.841499] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[7.841502] pc : __icc_enable (drivers/interconnect/core.c:685
(discriminator 7))
[7.841505] lr : icc_disable (drivers/interconnect/core.c:708)
[..]
[7.841541] Call trace:
[7.841542] __icc_enable (drivers/interconnect/core.c:685 (discriminator 7))
[7.841545] icc_disable (drivers/interconnect/core.c:708)
[7.841547] geni_icc_disable (drivers/soc/qcom/qcom-geni-se.c:862)
[7.841553] spi_geni_runtime_suspend+0x3c/0x4c spi_geni_qcom
[7.841561] pm_generic_runtime_suspend (drivers/base/power/generic_ops.c:28)
[7.841565] __rpm_callback (drivers/base/power/runtime.c:395)
[7.841568] rpm_callback (drivers/base/power/runtime.c:532)
[7.841570] rpm_suspend (drivers/base/power/runtime.c:672)
[7.841572] rpm_idle (drivers/base/power/runtime.c:504 (discriminator 1))
[7.841574] update_autosuspend (drivers/base/power/runtime.c:1662)
[7.841576] pm_runtime_disable_action (include/linux/spinlock.h:401
drivers/base/power/runtime.c:1703 include/linux/pm_runtime.h:599
drivers/base/power/runtime.c:1517)
[7.841579] devm_action_release (drivers/base/devres.c:720)
[7.841581] release_nodes (drivers/base/devres.c:503)
[7.841583] devres_release_all (drivers/base/devres.c:532)
[7.841585] device_unbind_cleanup (drivers/base/dd.c:531)
[7.841589] really_probe (drivers/base/dd.c:710)
[7.841592] __driver_probe_device (drivers/base/dd.c:785)
[7.841594] driver_probe_device (drivers/base/dd.c:815)
[7.841596] __driver_attach (drivers/base/dd.c:1202)
[7.841598] bus_for_each_dev (drivers/base/bus.c:301)
[7.841600] driver_attach (drivers/base/dd.c:1219)
[7.841602] bus_add_driver (drivers/base/bus.c:618)
[7.841604] driver_register (drivers/base/driver.c:246)
[7.841607] __platform_driver_register (drivers/base/platform.c:868)
[7.841609] spi_geni_driver_init+0x28/0x1000 spi_geni_qcom
[7.841615] do_one_initcall (init/main.c:1298)
[7.841619] do_init_module (kernel/module/main.c:2469)
[7.841623] load_module (kernel/module/main.c:2878)

[..]

This occurs when the spi-geni driver receives an -EPROBE_DEFER error from spi_geni_grab_gpi_chan(), causing devres to start releasing all resources as shown below:

[7.138679] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_icc_release (8 bytes)
[7.138751] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_icc_release (8 bytes)
[7.138827] geni_spi 880000.spi: DEVRES REL ffff800081443800 pm_runtime_disable_action (16 bytes)
[7.139494] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_pm_opp_config_release (16 bytes)
[7.139512] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_spi_release_controller (8 bytes)
[7.139516] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_clk_release (16 bytes)
[7.139519] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_ioremap_release (8 bytes)
[7.139524] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_region_release (24 bytes)
[7.139527] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_kzalloc_release (22 bytes)
[7.139530] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_pinctrl_release (8 bytes)
[7.139539] geni_spi 880000.spi: DEVRES REL ffff800081443800 devm_kzalloc_release (40 bytes)

The issue here is that pm_runtime_disable_action() results in a call to spi_geni_runtime_suspend(), which attempts to suspend the device and disable an interconnect path that devm_icc_release() has just released.

Resolve this by calling geni_icc_get() before enabling runtime PM. This approach ensures that when devres releases resources in reverse order, it will start with pm_runtime_disable_action(), suspending the device, and then proceed to free the remaining resources.

---
 drivers/spi/spi-geni-qcom.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

index f6e40f90418f..768d7482102a 100644
@@ -1116,6 +1116,11 @@ static int spi_geni_probe(struct platform_device *pdev)
 	init_completion(&mas->tx_reset_done);
 	init_completion(&mas->rx_reset_done);
 	spin_lock_init(&mas->lock);
+
+	ret = geni_icc_get(&mas->se, NULL);
+	if (ret)
+		return ret;
+
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_autosuspend_delay(&pdev->dev, 250);
 	ret = devm_pm_runtime_enable(dev);

@@ -1125,9 +1130,6 @@ static int spi_geni_probe(struct platform_device *pdev)
 	if (device_property_read_bool(&pdev->dev, "spi-slave"))
 		spi->target = true;
 
-	ret = geni_icc_get(&mas->se, NULL);
-	if (ret)
-		return ret;
 	/* Set the bus quota to a reasonable value for register access */
 	mas->se.icc_paths[GENI_TO_CORE].avg_bw = Bps_to_icc(CORE_2X_50_MHZ);
 	mas->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;

Please think hard before including complete backtraces in upstream reports, they are very large and contain almost no useful information relative to their size so often obscure the relevant content in your message. If part of the backtrace is usefully illustrative (it often is for search engines if nothing else) then it's usually better to pull out the relevant sections.

Applied to

https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: geni-qcom: Fix boot warning related to pm_runtime and devres

      commit: d0ccf760a405d243a49485be0a43bd5b66ed17e2

All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying to this mail.

Thanks,
Mark