[PATCH net-next v4 2/3] bus: mhi: host: pci_generic: enumerate IP_CTRL channel for Sierra EM919x/EM929x

IP_CTRL is a standard Qualcomm MHI control channel (channels 18/19) that
carries the host serial control lines (DTR/RTS) to the modem; it is not
Sierra-specific. It was not enumerated for any device in pci_generic, so
the host had no way to drive those signals.

Enumerate it in the Sierra em919x channel config (shared by the EM919x
and EM929x) using the control event ring. This is the device the change
was tested against; other Qualcomm modem configs that expose IP_CTRL can
enable it the same way, since the mhi_wwan_ctrl DTR support that consumes
it, added by the following patch in this series, is device-agnostic and
binds purely by channel name.

Reviewed-by: Loic Poulain <[email protected]>
Signed-off-by: Peter Hunt <[email protected]>
---
v4: Reword present-tense forward reference to the consumer in patch 3
---
 drivers/bus/mhi/host/pci_generic.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
index 0d0d9c7ffa4b..ba47dd153837 100644
--- a/drivers/bus/mhi/host/pci_generic.c
+++ b/drivers/bus/mhi/host/pci_generic.c
@@ -728,6 +728,8 @@ static const struct mhi_channel_config mhi_sierra_em919x_channels[] = {
 	MHI_CHANNEL_CONFIG_DL(13, "MBIM", 128, 0),
 	MHI_CHANNEL_CONFIG_UL(14, "QMI", 32, 0),
 	MHI_CHANNEL_CONFIG_DL(15, "QMI", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(18, "IP_CTRL", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(19, "IP_CTRL", 32, 0),
 	MHI_CHANNEL_CONFIG_UL(32, "DUN", 32, 0),
 	MHI_CHANNEL_CONFIG_DL(33, "DUN", 32, 0),
 	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0", 512, 1),
-- 
2.43.0