can: sja1000: of: add reg-io-width property for 8, 16 and 32-bit register access

Add the 'reg-io-width' property for 8, 16 and 32-bit access, like
what is currently done with IORESOURCE_MEM_{8,16,32}BIT for non-OF
boot.

Signed-off-by: Florian Vaussard <florian.vaussard@epfl.ch>
Tested-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

1 files changed, 18 insertions, 2 deletions

diff --git a/drivers/net/can/sja1000/sja1000_platform.c b/drivers/net/can/sja1000/sja1000_platform.c
index b7fbe4f57720..95a844a7ee7b 100644
--- a/drivers/net/can/sja1000/sja1000_platform.c
+++ b/drivers/net/can/sja1000/sja1000_platform.c
@@ -101,8 +101,24 @@ static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of)
         int err;
         u32 prop;
 
-        priv->read_reg = sp_read_reg8;
-        priv->write_reg = sp_write_reg8;
+        err = of_property_read_u32(of, "reg-io-width", &prop);
+        if (err)
+                prop = 1; /* 8 bit is default */
+
+        switch (prop) {
+        case 4:
+                priv->read_reg = sp_read_reg32;
+                priv->write_reg = sp_write_reg32;
+                break;
+        case 2:
+                priv->read_reg = sp_read_reg16;
+                priv->write_reg = sp_write_reg16;
+                break;
+        case 1: /* fallthrough */
+        default:
+                priv->read_reg = sp_read_reg8;
+                priv->write_reg = sp_write_reg8;
+        }
 
         err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
         if (!err)