[PATCH 2/2] dmaengine: fsl-edma: Add judgment on enabling round robin arbitration

From: Xiaolei Wang
Date: Mon Nov 13 2023 - 08:11:49 EST


Add judgment on enabling round robin arbitration to avoid
exceptions if this function is not supported.

Call trace:
fsl_edma_resume_early+0x1d4/0x208
dpm_run_callback+0xd4/0x304
device_resume_early+0xb0/0x208
dpm_resume_early+0x224/0x528
suspend_devices_and_enter+0x3e4/0xd00
pm_suspend+0x3c4/0x910
state_store+0x90/0x124
kobj_attr_store+0x48/0x64
sysfs_kf_write+0x84/0xb4
kernfs_fop_write_iter+0x19c/0x264
vfs_write+0x664/0x858
ksys_write+0xc8/0x180
__arm64_sys_write+0x44/0x58
invoke_syscall+0x5c/0x178
el0_svc_common.constprop.0+0x11c/0x14c
do_el0_svc+0x30/0x40
el0_svc+0x58/0xa8
el0t_64_sync_handler+0xc0/0xc4
el0t_64_sync+0x190/0x194

Fixes: 82d149b86d31 ("dmaengine: fsl-edma: add PM suspend/resume support")
Signed-off-by: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx>
---
drivers/dma/fsl-edma-main.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/fsl-edma-main.c b/drivers/dma/fsl-edma-main.c
index 52577fffc62b..aea7a703dda7 100644
--- a/drivers/dma/fsl-edma-main.c
+++ b/drivers/dma/fsl-edma-main.c
@@ -665,7 +665,8 @@ static int fsl_edma_resume_early(struct device *dev)
fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
}

- edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
+ if (!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
+ edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);

return 0;
}
--
2.25.1