[PATCH] mmc: sdhci-of-dwcmshc: don't enable CQE without a suitable irq handler

From: Heiko Stuebner
Date: Thu May 30 2024 - 17:55:59 EST


From: Heiko Stuebner <heiko.stuebner@xxxxxxxxx>

supports-cqe is an established dt property so can appear in devicetrees
at any time. CQE support in the sdhci-of-dwcmshc driver does require a
special irq handler in the platform-specific ops, to handle the CQE
interrupt.

Without this special handler we end up with a spew of unhandled interrupt
messages on devices with supports-cqe property but without irq handler:

[ 11.624143] mmc0: Unexpected interrupt 0x00004000.
[ 11.629504] mmc0: sdhci: ============ SDHCI REGISTER DUMP ===========
[ 11.636711] mmc0: sdhci: Sys addr: 0x00000008 | Version: 0x00000005
[ 11.643919] mmc0: sdhci: Blk size: 0x00007200 | Blk cnt: 0x00000000
[ 11.651128] mmc0: sdhci: Argument: 0x00018000 | Trn mode: 0x00000033
[ 11.658336] mmc0: sdhci: Present: 0x13f700f0 | Host ctl: 0x00000034
[ 11.665545] mmc0: sdhci: Power: 0x00000001 | Blk gap: 0x00000000
[ 11.672753] mmc0: sdhci: Wake-up: 0x00000000 | Clock: 0x00000407
[ 11.679961] mmc0: sdhci: Timeout: 0x0000000e | Int stat: 0x00004000
[ 11.687169] mmc0: sdhci: Int enab: 0x02ff4000 | Sig enab: 0x02ff4000
[ 11.694378] mmc0: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000000
[ 11.701586] mmc0: sdhci: Caps: 0x226dc881 | Caps_1: 0x08000007
[ 11.708794] mmc0: sdhci: Cmd: 0x00000d1e | Max curr: 0x00000000
[ 11.716003] mmc0: sdhci: Resp[0]: 0x00000900 | Resp[1]: 0x00000000
[ 11.723211] mmc0: sdhci: Resp[2]: 0x328f5903 | Resp[3]: 0x000007cd
[ 11.730419] mmc0: sdhci: Host ctl2: 0x0000000f
[ 11.735392] mmc0: sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0xee28f008
[ 11.742600] mmc0: sdhci: ============================================

So don't enable CQE if a usable interrupt handler is not defined and warn
instead about this fact.

Fixes: 53ab7f7fe412 ("mmc: sdhci-of-dwcmshc: Implement SDHCI CQE support")
Signed-off-by: Heiko Stuebner <heiko.stuebner@xxxxxxxxx>
---
My rk3588-tiger and rk3588-jaguar devicetrees had an accidential
supports-cqe in their devicetree, which made me run into this problem
with 6.10-rc1 .

drivers/mmc/host/sdhci-of-dwcmshc.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
index 39edf04fedcf7..4410d4523728d 100644
--- a/drivers/mmc/host/sdhci-of-dwcmshc.c
+++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
@@ -1254,10 +1254,14 @@ static int dwcmshc_probe(struct platform_device *pdev)

/* Setup Command Queue Engine if enabled */
if (device_property_read_bool(&pdev->dev, "supports-cqe")) {
- priv->vendor_specific_area2 =
- sdhci_readw(host, DWCMSHC_P_VENDOR_AREA2);
+ if (pltfm_data && pltfm_data->ops && pltfm_data->ops->irq) {
+ priv->vendor_specific_area2 =
+ sdhci_readw(host, DWCMSHC_P_VENDOR_AREA2);

- dwcmshc_cqhci_init(host, pdev);
+ dwcmshc_cqhci_init(host, pdev);
+ } else {
+ dev_warn(&pdev->dev, "can't enable cqe support without irq handler\n");
+ }
}

if (rk_priv)
--
2.39.2