Convert CAN Control Register field accesses to use the FIELD_PREP()
bitfield access macro. Add a few more comments and definitions while at
it.
This gets rid of explicit (and sometimes confusing) shifts.
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
drivers/net/can/rcar/rcar_can.c | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)
diff --git a/drivers/net/can/rcar/rcar_can.c b/drivers/net/can/rcar/rcar_can.c
index 7f0b58793cf1734b..b7b5f4cd3c3afd20 100644
--- a/drivers/net/can/rcar/rcar_can.c
+++ b/drivers/net/can/rcar/rcar_can.c
@@ -5,6 +5,7 @@
* Copyright (C) 2013 Renesas Solutions Corp.
*/
+#include <linux/bitfield.h>
#include <linux/bits.h>
#include <linux/module.h>
#include <linux/kernel.h>
@@ -115,16 +116,19 @@ static const struct can_bittiming_const rcar_can_bittiming_const = {
/* Control Register bits */
#define RCAR_CAN_CTLR_BOM GENMASK(12, 11) /* Bus-Off Recovery Mode Bits */
-#define RCAR_CAN_CTLR_BOM_ENT (1 << 11) /* Entry to halt mode */
- /* at bus-off entry */
+#define RCAR_CAN_CTLR_BOM_ENT 1 /* Entry to halt mode */
+ /* at bus-off entry */
#define RCAR_CAN_CTLR_SLPM BIT(10) /* Sleep Mode */
#define RCAR_CAN_CTLR_CANM GENMASK(9, 8) /* Operating Mode Select Bit */
-#define RCAR_CAN_CTLR_CANM_HALT (1 << 9)
-#define RCAR_CAN_CTLR_CANM_RESET (1 << 8)
-#define RCAR_CAN_CTLR_CANM_FORCE_RESET (3 << 8)
+#define RCAR_CAN_CTLR_CANM_OPER 0 /* Operation Mode */
+#define RCAR_CAN_CTLR_CANM_RESET 1 /* Reset Mode */
+#define RCAR_CAN_CTLR_CANM_HALT 2 /* Halt Mode */
+#define RCAR_CAN_CTLR_CANM_FORCE_RESET 3 /* Reset Mode (forcible) */
#define RCAR_CAN_CTLR_MLM BIT(3) /* Message Lost Mode Select */
#define RCAR_CAN_CTLR_IDFM GENMASK(2, 1) /* ID Format Mode Select Bits */
-#define RCAR_CAN_CTLR_IDFM_MIXED (1 << 2) /* Mixed ID mode */
+#define RCAR_CAN_CTLR_IDFM_STD 0 /* Standard ID mode */
+#define RCAR_CAN_CTLR_IDFM_EXT 1 /* Extended ID mode */
+#define RCAR_CAN_CTLR_IDFM_MIXED 2 /* Mixed ID mode */
#define RCAR_CAN_CTLR_MBM BIT(0) /* Mailbox Mode select */
/* Status Register bits */
@@ -453,16 +457,17 @@ static void rcar_can_start(struct net_device *ndev)
ctlr &= ~RCAR_CAN_CTLR_SLPM;
writew(ctlr, &priv->regs->ctlr);
/* Go to reset mode */
- ctlr |= RCAR_CAN_CTLR_CANM_FORCE_RESET;
+ ctlr |= FIELD_PREP(RCAR_CAN_CTLR_CANM, RCAR_CAN_CTLR_CANM_FORCE_RESET);
writew(ctlr, &priv->regs->ctlr);
for (i = 0; i < MAX_STR_READS; i++) {
if (readw(&priv->regs->str) & RCAR_CAN_STR_RSTST)
break;
}
rcar_can_set_bittiming(ndev);
- ctlr |= RCAR_CAN_CTLR_IDFM_MIXED; /* Select mixed ID mode */
- ctlr |= RCAR_CAN_CTLR_BOM_ENT; /* Entry to halt mode automatically */
- /* at bus-off */
+ /* Select mixed ID mode */
+ ctlr |= FIELD_PREP(RCAR_CAN_CTLR_IDFM, RCAR_CAN_CTLR_IDFM_MIXED);
+ /* Entry to halt mode automatically at bus-off */
+ ctlr |= FIELD_PREP(RCAR_CAN_CTLR_BOM, RCAR_CAN_CTLR_BOM_ENT);
ctlr |= RCAR_CAN_CTLR_MBM; /* Select FIFO mailbox mode */
ctlr |= RCAR_CAN_CTLR_MLM; /* Overrun mode */
writew(ctlr, &priv->regs->ctlr);
@@ -492,7 +497,9 @@ static void rcar_can_start(struct net_device *ndev)
priv->can.state = CAN_STATE_ERROR_ACTIVE;
/* Go to operation mode */
- writew(ctlr & ~RCAR_CAN_CTLR_CANM, &priv->regs->ctlr);
+ ctlr &= ~RCAR_CAN_CTLR_CANM;
+ ctlr |= FIELD_PREP(RCAR_CAN_CTLR_CANM, RCAR_CAN_CTLR_CANM_OPER);
+ writew(ctlr, &priv->regs->ctlr);
for (i = 0; i < MAX_STR_READS; i++) {
if (!(readw(&priv->regs->str) & RCAR_CAN_STR_RSTST))
break;
@@ -554,7 +561,7 @@ static void rcar_can_stop(struct net_device *ndev)
/* Go to (force) reset mode */
ctlr = readw(&priv->regs->ctlr);
- ctlr |= RCAR_CAN_CTLR_CANM_FORCE_RESET;
+ ctlr |= FIELD_PREP(RCAR_CAN_CTLR_CANM, RCAR_CAN_CTLR_CANM_FORCE_RESET);
writew(ctlr, &priv->regs->ctlr);
for (i = 0; i < MAX_STR_READS; i++) {
if (readw(&priv->regs->str) & RCAR_CAN_STR_RSTST)
@@ -848,7 +855,7 @@ static int rcar_can_suspend(struct device *dev)
netif_device_detach(ndev);
ctlr = readw(&priv->regs->ctlr);
- ctlr |= RCAR_CAN_CTLR_CANM_HALT;
+ ctlr |= FIELD_PREP(RCAR_CAN_CTLR_CANM, RCAR_CAN_CTLR_CANM_HALT);
writew(ctlr, &priv->regs->ctlr);
ctlr |= RCAR_CAN_CTLR_SLPM;
writew(ctlr, &priv->regs->ctlr);
--
2.43.0
