[PATCH v3 1/4] can: dev: replace can_priv::ctrlmode_static by can_get_static_ctrlmode()

From: Vincent Mailhol
Date: Mon Oct 25 2021 - 13:23:35 EST


The statically enabled features of a CAN controller can be retrieved
using below formula:

| u32 ctrlmode_static = priv->ctrlmode & ~priv->ctrlmode_supported;

As such, there is no need to store this information. This patch
removes the field ctrlmode_static of struct can_priv and provides, in
replacement, the inline function can_get_static_ctrlmode() which
returns the same value.

Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
---
drivers/net/can/dev/dev.c | 5 +++--
drivers/net/can/dev/netlink.c | 2 +-
include/linux/can/dev.h | 7 +++++--
3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c
index e3d840b81357..59c79f92fccc 100644
--- a/drivers/net/can/dev/dev.c
+++ b/drivers/net/can/dev/dev.c
@@ -300,6 +300,7 @@ EXPORT_SYMBOL_GPL(free_candev);
int can_change_mtu(struct net_device *dev, int new_mtu)
{
struct can_priv *priv = netdev_priv(dev);
+ u32 ctrlmode_static = can_get_static_ctrlmode(priv);

/* Do not allow changing the MTU while running */
if (dev->flags & IFF_UP)
@@ -309,7 +310,7 @@ int can_change_mtu(struct net_device *dev, int new_mtu)
switch (new_mtu) {
case CAN_MTU:
/* 'CANFD-only' controllers can not switch to CAN_MTU */
- if (priv->ctrlmode_static & CAN_CTRLMODE_FD)
+ if (ctrlmode_static & CAN_CTRLMODE_FD)
return -EINVAL;

priv->ctrlmode &= ~CAN_CTRLMODE_FD;
@@ -318,7 +319,7 @@ int can_change_mtu(struct net_device *dev, int new_mtu)
case CANFD_MTU:
/* check for potential CANFD ability */
if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD) &&
- !(priv->ctrlmode_static & CAN_CTRLMODE_FD))
+ !(ctrlmode_static & CAN_CTRLMODE_FD))
return -EINVAL;

priv->ctrlmode |= CAN_CTRLMODE_FD;
diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
index 95cca4e5251f..26c336808be5 100644
--- a/drivers/net/can/dev/netlink.c
+++ b/drivers/net/can/dev/netlink.c
@@ -211,7 +211,7 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
if (dev->flags & IFF_UP)
return -EBUSY;
cm = nla_data(data[IFLA_CAN_CTRLMODE]);
- ctrlstatic = priv->ctrlmode_static;
+ ctrlstatic = can_get_static_ctrlmode(priv);
maskedflags = cm->flags & cm->mask;

/* check whether provided bits are allowed to be passed */
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index 45f19d9db5ca..92e2d69462f0 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -69,7 +69,6 @@ struct can_priv {
/* CAN controller features - see include/uapi/linux/can/netlink.h */
u32 ctrlmode; /* current options setting */
u32 ctrlmode_supported; /* options that can be modified by netlink */
- u32 ctrlmode_static; /* static enabled options for driver/hardware */

int restart_ms;
struct delayed_work restart_work;
@@ -139,13 +138,17 @@ static inline void can_set_static_ctrlmode(struct net_device *dev,

/* alloc_candev() succeeded => netdev_priv() is valid at this point */
priv->ctrlmode = static_mode;
- priv->ctrlmode_static = static_mode;

/* override MTU which was set by default in can_setup()? */
if (static_mode & CAN_CTRLMODE_FD)
dev->mtu = CANFD_MTU;
}

+static inline u32 can_get_static_ctrlmode(struct can_priv *priv)
+{
+ return priv->ctrlmode & ~priv->ctrlmode_supported;
+}
+
void can_setup(struct net_device *dev);

struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
--
2.32.0