net: mvneta: remove data pointer usage from device_node structure

On year ago Rob Herring wanted to remove the data pointer from the
device_node structure[1]. The mvneta driver seemed to be the only one
which used (abused ?) it. However, the proposal of Rob to remove this
pointer from the driver introduced a regression, and I tested and fixed an
alternative way, but it was never submitted as a proper patch.

Now here it is: Instead of using the device_node structure ->data
pointer, we store the BM private data as the driver data of the BM
platform_device. The core mvneta code can retrieve it by doing a lookup
on which platform_device corresponds to the BM device tree node using
of_find_device_by_node(), and get its driver data

[1]https://www.spinics.net/lists/netdev/msg445197.html

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/net/ethernet/marvell/mvneta_bm.c b/drivers/net/ethernet/marvell/mvneta_bm.c
index 466939f8f0cf..de468e1bdba9 100644
--- a/drivers/net/ethernet/marvell/mvneta_bm.c
+++ b/drivers/net/ethernet/marvell/mvneta_bm.c
@@ -18,6 +18,7 @@
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/skbuff.h>
 #include <net/hwbm.h>
@@ -392,6 +393,20 @@ static void mvneta_bm_put_sram(struct mvneta_bm *priv)
 		      MVNETA_BM_BPPI_SIZE);
 }
 
+struct mvneta_bm *mvneta_bm_get(struct device_node *node)
+{
+	struct platform_device *pdev = of_find_device_by_node(node);
+
+	return pdev ? platform_get_drvdata(pdev) : NULL;
+}
+EXPORT_SYMBOL_GPL(mvneta_bm_get);
+
+void mvneta_bm_put(struct mvneta_bm *priv)
+{
+	platform_device_put(priv->pdev);
+}
+EXPORT_SYMBOL_GPL(mvneta_bm_put);
+
 static int mvneta_bm_probe(struct platform_device *pdev)
 {
 	struct device_node *dn = pdev->dev.of_node;