[PATCH v2 3/7] fpga-mgr: wrap the write() op

[trix at redhat.com]

From: Tom Rix <trix at redhat.com>

An FPGA manager should not be required to provide a
write function. Move the op check to the wrapper.
Default to -EOPNOTSUP so its users will fail
gracefully.

Signed-off-by: Tom Rix <trix at redhat.com>
---
 drivers/fpga/fpga-mgr.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index dadad24015020..c484b4309b2f4 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -167,6 +167,13 @@ static int fpga_mgr_write_complete(struct fpga_manager *mgr,
 	return 0;
 }
 
+static int fpga_mgr_write(struct fpga_manager *mgr, const char *buf, size_t count)
+{
+	if (mgr->mops && mgr->mops->write)
+		return  mgr->mops->write(mgr, buf, count);
+	return -EOPNOTSUPP;
+}
+
 /**
  * fpga_mgr_buf_load_sg - load fpga from image in buffer from a scatter list
  * @mgr:	fpga manager
@@ -203,7 +210,7 @@ static int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
 
 		sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
 		while (sg_miter_next(&miter)) {
-			ret = mgr->mops->write(mgr, miter.addr, miter.length);
+			ret = fpga_mgr_write(mgr, miter.addr, miter.length);
 			if (ret)
 				break;
 		}
@@ -233,7 +240,7 @@ static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
 	 * Write the FPGA image to the FPGA.
 	 */
 	mgr->state = FPGA_MGR_STATE_WRITE;
-	ret = mgr->mops->write(mgr, buf, count);
+	ret = fpga_mgr_write(mgr, buf, count);
 	if (ret) {
 		dev_err(&mgr->dev, "Error while writing image data to FPGA\n");
 		mgr->state = FPGA_MGR_STATE_WRITE_ERR;
@@ -577,9 +584,7 @@ struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
 	struct fpga_manager *mgr;
 	int id, ret;
 
-	if (!mops || !mops->state ||
-	    (!mops->write && !mops->write_sg) ||
-	    (mops->write && mops->write_sg)) {
+	if (!mops || !mops->state) {
 		dev_err(dev, "Attempt to register without fpga_manager_ops\n");
 		return NULL;
 	}
-- 
2.26.3