[PATCH v1 3/3] mmc: core: Set cqe off during suspend flow

[Wenbin Mei]

Before we got these errors on MT8192 platform:
[   59.153891] Restarting tasks ...
[   59.154540] done.
[   59.159175] PM: suspend exit
[   59.218724] mtk-msdc 11f60000.mmc: phase: [map:fffffffe] [maxlen:31]
[final:16]
[  119.776083] mmc0: cqhci: timeout for tag 9
[  119.780196] mmc0: cqhci: ============ CQHCI REGISTER DUMP ===========
[  119.786709] mmc0: cqhci: Caps:      0x100020b6 | Version:  0x00000510
[  119.793225] mmc0: cqhci: Config:    0x00000101 | Control:  0x00000000
[  119.799706] mmc0: cqhci: Int stat:  0x00000000 | Int enab: 0x00000000
[  119.806177] mmc0: cqhci: Int sig:   0x00000000 | Int Coal: 0x00000000
[  119.812670] mmc0: cqhci: TDL base:  0x00000000 | TDL up32: 0x00000000
[  119.819149] mmc0: cqhci: Doorbell:  0x003ffc00 | TCN:      0x00000200
[  119.825656] mmc0: cqhci: Dev queue: 0x00000000 | Dev Pend: 0x00000000
[  119.832155] mmc0: cqhci: Task clr:  0x00000000 | SSC1:     0x00001000
[  119.838627] mmc0: cqhci: SSC2:      0x00000000 | DCMD rsp: 0x00000000
[  119.845174] mmc0: cqhci: RED mask:  0xfdf9a080 | TERRI:    0x0000891c
[  119.851654] mmc0: cqhci: Resp idx:  0x00000000 | Resp arg: 0x00000000
[  119.865773] mmc0: cqhci: : ===========================================
[  119.872358] mmc0: running CQE recovery
From these logs, we found TDL base was back to the default value.

After suspend, the mmc host is powered off by HW, and bring CQE register
to the default value, so CQE need to be re-initialized after resuming back.

Signed-off-by: Wenbin Mei <wenbin.mei at mediatek.com>
---
 drivers/mmc/core/host.c | 2 ++
 drivers/mmc/core/mmc.c  | 5 +++++
 include/linux/mmc/pm.h  | 1 +
 3 files changed, 8 insertions(+)

diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index ce43f7573d80..c98486c8fb3b 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -284,6 +284,8 @@ int mmc_of_parse(struct mmc_host *host)
 	if (device_property_read_bool(dev, "wakeup-source") ||
 	    device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
 		host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
+	if (device_property_read_bool(dev, "cqe-off-in-suspend"))
+		host->pm_caps |= MMC_PM_CQE_OFF_IN_SUSPEND;
 	if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
 		host->caps |= MMC_CAP_3_3V_DDR;
 	if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index b3fa193de846..f5ae1f13a867 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -2047,6 +2047,11 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
 		err = mmc_deselect_cards(host);
 
 	if (!err) {
+		if (host->cqe_enabled &&
+		    (host->pm_caps & MMC_PM_CQE_OFF_IN_SUSPEND)) {
+			host->cqe_ops->cqe_disable(host);
+			host->cqe_enabled = false;
+		}
 		mmc_power_off(host);
 		mmc_card_set_suspended(host->card);
 	}
diff --git a/include/linux/mmc/pm.h b/include/linux/mmc/pm.h
index 3549f8045784..3dd1046f2c8f 100644
--- a/include/linux/mmc/pm.h
+++ b/include/linux/mmc/pm.h
@@ -23,5 +23,6 @@ typedef unsigned int mmc_pm_flag_t;
 
 #define MMC_PM_KEEP_POWER	(1 << 0)	/* preserve card power during suspend */
 #define MMC_PM_WAKE_SDIO_IRQ	(1 << 1)	/* wake up host system on SDIO IRQ assertion */
+#define MMC_PM_CQE_OFF_IN_SUSPEND  (1 << 2)	/* cqe off during suspend */
 
 #endif /* LINUX_MMC_PM_H */
-- 
2.18.0