fpga: manager: change api, don't use drvdata

Change fpga_mgr_register to not set or use drvdata.  This supports
the case where a PCIe device has more than one manager.

Add fpga_mgr_create/free functions.  Change fpga_mgr_register and
fpga_mgr_unregister functions to take the mgr struct as their only
parameter.

  struct fpga_manager *fpga_mgr_create(struct device *dev,
                const char *name,
                const struct fpga_manager_ops *mops,
                void *priv);
  void fpga_mgr_free(struct fpga_manager *mgr);
  int fpga_mgr_register(struct fpga_manager *mgr);
  void fpga_mgr_unregister(struct fpga_manager *mgr);

Update the drivers that call fpga_mgr_register with the new API.

Signed-off-by: Alan Tull <atull@kernel.org>
[Moritz: Fixup whitespace issue]
Reported-by: Jiuyue Ma <majiuyue@huawei.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/fpga/xilinx-spi.c b/drivers/fpga/xilinx-spi.c
index 9b62a4c..8d19459 100644
--- a/drivers/fpga/xilinx-spi.c
+++ b/drivers/fpga/xilinx-spi.c
@@ -143,6 +143,8 @@ static const struct fpga_manager_ops xilinx_spi_ops = {
 static int xilinx_spi_probe(struct spi_device *spi)
 {
 	struct xilinx_spi_conf *conf;
+	struct fpga_manager *mgr;
+	int ret;
 
 	conf = devm_kzalloc(&spi->dev, sizeof(*conf), GFP_KERNEL);
 	if (!conf)
@@ -165,13 +167,25 @@ static int xilinx_spi_probe(struct spi_device *spi)
 		return PTR_ERR(conf->done);
 	}
 
-	return fpga_mgr_register(&spi->dev, "Xilinx Slave Serial FPGA Manager",
-				 &xilinx_spi_ops, conf);
+	mgr = fpga_mgr_create(&spi->dev, "Xilinx Slave Serial FPGA Manager",
+			      &xilinx_spi_ops, conf);
+	if (!mgr)
+		return -ENOMEM;
+
+	spi_set_drvdata(spi, mgr);
+
+	ret = fpga_mgr_register(mgr);
+	if (ret)
+		fpga_mgr_free(mgr);
+
+	return ret;
 }
 
 static int xilinx_spi_remove(struct spi_device *spi)
 {
-	fpga_mgr_unregister(&spi->dev);
+	struct fpga_manager *mgr = spi_get_drvdata(spi);
+
+	fpga_mgr_unregister(mgr);
 
 	return 0;
 }