[RFC] fpga: Pull checks for supported operations into framework

[Moritz Fischer]

Most of the drivers only support a subset of {PARTIAL, FULL}
reconfiguration.
Pull duplicate checks in each driver into the framework.

Signed-off-by: Moritz Fischer <moritz.fischer@xxxxxxxxx>
Cc: Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx>
Cc: Michal Simek <michal.simek@xxxxxxxxxx>
Cc: SÃren Brinkmann <soren.brinkmann@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
---
Hi all,

with the new drivers (ice40, altera-ps-spi) being submitted I've noticed
we're duplicating this check over and over again,
so I figured we might as well pull it into the framework.

I'm not sure if there are gonna be other 'flags' we need to support
in the short term (we talked about byte-swapping ...)

Note: This patch goes on top of greg's char-misc-testing  that already
contains Alan's latest changes to support the A10 and won't apply 
to master.

Cheers,

Moritz

---
 drivers/fpga/fpga-mgr.c       | 12 ++++++++++++
 drivers/fpga/socfpga-a10.c    |  4 +++-
 drivers/fpga/socfpga.c        |  3 ++-
 drivers/fpga/zynq-fpga.c      |  3 ++-
 include/linux/fpga/fpga-mgr.h |  9 +++++++--
 5 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index c58b4c4..85f17d8 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -49,6 +49,11 @@ int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
 	struct device *dev = &mgr->dev;
 	int ret;
 
+	if (!(mgr->supported_flags & info->flags)) {
+		dev_err(dev, "Unsupported flags passed\n");
+		return -ENOTSUPP;
+	}
+
 	/*
 	 * Call the low level driver's write_init function.  This will do the
 	 * device-specific things to get the FPGA into the state where it is
@@ -252,6 +257,7 @@ EXPORT_SYMBOL_GPL(fpga_mgr_put);
  */
 int fpga_mgr_register(struct device *dev, const char *name,
 		      const struct fpga_manager_ops *mops,
+		      u32 supported_flags,
 		      void *priv)
 {
 	struct fpga_manager *mgr;
@@ -268,6 +274,11 @@ int fpga_mgr_register(struct device *dev, const char *name,
 		return -EINVAL;
 	}
 
+	if (!supported_flags) {
+		dev_err(dev, "Attempt to register with no supported flags\n");
+		return -EINVAL;
+	}
+
 	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
 	if (!mgr)
 		return -ENOMEM;
@@ -282,6 +293,7 @@ int fpga_mgr_register(struct device *dev, const char *name,
 
 	mgr->name = name;
 	mgr->mops = mops;
+	mgr->supported_flags = supported_flags;
 	mgr->priv = priv;
 
 	/*
diff --git a/drivers/fpga/socfpga-a10.c b/drivers/fpga/socfpga-a10.c
index ccd9fb2..e7c82ff 100644
--- a/drivers/fpga/socfpga-a10.c
+++ b/drivers/fpga/socfpga-a10.c
@@ -519,7 +519,9 @@ static int socfpga_a10_fpga_probe(struct platform_device *pdev)
 	}
 
 	return fpga_mgr_register(dev, "SoCFPGA Arria10 FPGA Manager",
-				 &socfpga_a10_fpga_mgr_ops, priv);
+				 &socfpga_a10_fpga_mgr_ops,
+				 FPGA_MGR_PARTIAL_RECONFIG,
+				 priv);
 }
 
 static int socfpga_a10_fpga_remove(struct platform_device *pdev)
diff --git a/drivers/fpga/socfpga.c b/drivers/fpga/socfpga.c
index b6672e6..3285b7d 100644
--- a/drivers/fpga/socfpga.c
+++ b/drivers/fpga/socfpga.c
@@ -582,7 +582,8 @@ static int socfpga_fpga_probe(struct platform_device *pdev)
 		return ret;
 
 	return fpga_mgr_register(dev, "Altera SOCFPGA FPGA Manager",
-				 &socfpga_fpga_ops, priv);
+				 &socfpga_fpga_ops, FPGA_MGR_FULL_RECONFIG,
+				 priv);
 }
 
 static int socfpga_fpga_remove(struct platform_device *pdev)
diff --git a/drivers/fpga/zynq-fpga.c b/drivers/fpga/zynq-fpga.c
index 249682e..1dabd25 100644
--- a/drivers/fpga/zynq-fpga.c
+++ b/drivers/fpga/zynq-fpga.c
@@ -413,6 +413,7 @@ static int zynq_fpga_probe(struct platform_device *pdev)
 	struct zynq_fpga_priv *priv;
 	struct resource *res;
 	int err;
+	u32 flags = FPGA_MGR_FULL_RECONFIG | FPGA_MGR_PARTIAL_RECONFIG;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -465,7 +466,7 @@ static int zynq_fpga_probe(struct platform_device *pdev)
 	clk_disable(priv->clk);
 
 	err = fpga_mgr_register(dev, "Xilinx Zynq FPGA Manager",
-				&zynq_fpga_ops, priv);
+				&zynq_fpga_ops, flags, priv);
 	if (err) {
 		dev_err(dev, "unable to register FPGA manager");
 		clk_unprepare(priv->clk);
diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index 040b86d..4f4bcf2 100644
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -64,9 +64,12 @@ enum fpga_mgr_states {
 
 /*
  * FPGA Manager flags
+ * FPGA_MGR_FULL_RECONFIG: do full reconfiguration if supported
  * FPGA_MGR_PARTIAL_RECONFIG: do partial reconfiguration if supported
  */
-#define FPGA_MGR_PARTIAL_RECONFIG	BIT(0)
+#define FPGA_MGR_FULL_RECONFIG		BIT(0)
+#define FPGA_MGR_PARTIAL_RECONFIG	BIT(1)
+#define FPGA_MGR_EXTERNAL_CONFIG	BIT(2)
 
 /**
  * struct fpga_image_info - information specific to a FPGA image
@@ -119,6 +122,7 @@ struct fpga_manager {
 	enum fpga_mgr_states state;
 	const struct fpga_manager_ops *mops;
 	void *priv;
+	u32 supported_flags;
 };
 
 #define to_fpga_manager(d) container_of(d, struct fpga_manager, dev)
@@ -135,7 +139,8 @@ struct fpga_manager *of_fpga_mgr_get(struct device_node *node);
 void fpga_mgr_put(struct fpga_manager *mgr);
 
 int fpga_mgr_register(struct device *dev, const char *name,
-		      const struct fpga_manager_ops *mops, void *priv);
+		      const struct fpga_manager_ops *mops, u32 supported_flags,
+		      void *priv);
 
 void fpga_mgr_unregister(struct device *dev);
 
-- 
2.4.11