[PATCH] firmware: arm_scmi: Fix sparse warnings in OPTEE transport driver

From: Sudeep Holla
Date: Mon Apr 04 2022 - 06:24:42 EST


The sparse checker complains about converting pointers between address
spaces. We correctly stored an __iomem pointer in struct scmi_optee_channel,
but discarded the __iomem when returning it from get_channel_shm, causing one
warning. Then we passed the non-__iomem pointer return from get_channel_shm
at tow other places, where an __iomem pointer is expected, causing couple of
other warnings

Add the appropriate __iomem annotations at all places where it is missing.

optee.c:414:20: warning: incorrect type in return expression (different address spaces)
optee.c:414:20: expected struct scmi_shared_mem *
optee.c:414:20: got struct scmi_shared_mem [noderef] __iomem *shmem
optee.c:426:26: warning: incorrect type in argument 1 (different address spaces)
optee.c:426:26: expected struct scmi_shared_mem [noderef] __iomem *shmem
optee.c:426:26: got struct scmi_shared_mem *shmem
optee.c:441:30: warning: incorrect type in argument 1 (different address spaces)
optee.c:441:30: expected struct scmi_shared_mem [noderef] __iomem *shmem
optee.c:441:30: got struct scmi_shared_mem *shmem

Cc: Etienne Carriere <etienne.carriere@xxxxxxxxxx>
Cc: Cristian Marussi <cristian.marussi@xxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
---
drivers/firmware/arm_scmi/optee.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c
index 734f1eeee161..8302a2b4aeeb 100644
--- a/drivers/firmware/arm_scmi/optee.c
+++ b/drivers/firmware/arm_scmi/optee.c
@@ -405,8 +405,8 @@ static int scmi_optee_chan_free(int id, void *p, void *data)
return 0;
}

-static struct scmi_shared_mem *get_channel_shm(struct scmi_optee_channel *chan,
- struct scmi_xfer *xfer)
+static struct scmi_shared_mem __iomem *
+get_channel_shm(struct scmi_optee_channel *chan, struct scmi_xfer *xfer)
{
if (!chan)
return NULL;
@@ -419,7 +419,7 @@ static int scmi_optee_send_message(struct scmi_chan_info *cinfo,
struct scmi_xfer *xfer)
{
struct scmi_optee_channel *channel = cinfo->transport_info;
- struct scmi_shared_mem *shmem = get_channel_shm(channel, xfer);
+ struct scmi_shared_mem __iomem *shmem = get_channel_shm(channel, xfer);
int ret;

mutex_lock(&channel->mu);
@@ -436,7 +436,7 @@ static void scmi_optee_fetch_response(struct scmi_chan_info *cinfo,
struct scmi_xfer *xfer)
{
struct scmi_optee_channel *channel = cinfo->transport_info;
- struct scmi_shared_mem *shmem = get_channel_shm(channel, xfer);
+ struct scmi_shared_mem __iomem *shmem = get_channel_shm(channel, xfer);

shmem_fetch_response(shmem, xfer);
}
--
2.35.1