[PATCH v3 16/19] bus: mhi: core: Allow shared IRQ for event rings

From: Manivannan Sadhasivam
Date: Tue Sep 29 2020 - 13:53:54 EST


From: Loic Poulain <loic.poulain@xxxxxxxxxx>

There is no requirement for using a dedicated IRQ per event ring.
Some systems does not support multiple MSI vectors (e.g. intel
without CONFIG_IRQ_REMAP), In that case the MHI controller can
configure all the event rings to use the same interrupt (as fallback).

Allow this by removing the nr_irqs = ev_ring test and add extra check
in the irq_setup function.

Signed-off-by: Loic Poulain <loic.poulain@xxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/bus/mhi/core/init.c | 7 +++++++
drivers/bus/mhi/core/pm.c | 2 +-
2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index a33665b7ee54..103d51f35e28 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -162,6 +162,13 @@ int mhi_init_irq_setup(struct mhi_controller *mhi_cntrl)
if (mhi_event->offload_ev)
continue;

+ if (mhi_event->irq >= mhi_cntrl->nr_irqs) {
+ dev_err(dev, "irq %d not available for event ring\n",
+ mhi_event->irq);
+ ret = -EINVAL;
+ goto error_request;
+ }
+
ret = request_irq(mhi_cntrl->irq[mhi_event->irq],
mhi_irq_handler,
IRQF_SHARED | IRQF_NO_SUSPEND,
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index ce4d969818b4..3de7b1639ec6 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -918,7 +918,7 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)

dev_info(dev, "Requested to power ON\n");

- if (mhi_cntrl->nr_irqs < mhi_cntrl->total_ev_rings)
+ if (mhi_cntrl->nr_irqs < 1)
return -EINVAL;

/* Supply default wake routines if not provided by controller driver */
--
2.17.1