[PATCH net-next] net: phy: constify phydev->drv

[Russell King (Oracle)]

Device driver structures are shared between all devices that they
match, and thus nothing should never write to the device driver
structure through the phydev->drv pointer. Let's make this pointer
const to catch code that attempts to do so.

Suggested-by: Christian Marangi <ansuelsmth at gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>
---
 drivers/net/phy/phy.c               | 3 +--
 drivers/net/phy/phy_device.c        | 6 +++---
 drivers/net/phy/xilinx_gmii2rgmii.c | 2 +-
 include/linux/phy.h                 | 2 +-
 4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 3b9531143be1..14224e06d69f 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -1290,7 +1290,6 @@ int phy_disable_interrupts(struct phy_device *phydev)
 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 {
 	struct phy_device *phydev = phy_dat;
-	struct phy_driver *drv = phydev->drv;
 	irqreturn_t ret;
 
 	/* Wakeup interrupts may occur during a system sleep transition.
@@ -1316,7 +1315,7 @@ static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 	}
 
 	mutex_lock(&phydev->lock);
-	ret = drv->handle_interrupt(phydev);
+	ret = phydev->drv->handle_interrupt(phydev);
 	mutex_unlock(&phydev->lock);
 
 	return ret;
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 52828d1c64f7..2eed8f03621d 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1413,7 +1413,7 @@ int phy_sfp_probe(struct phy_device *phydev,
 }
 EXPORT_SYMBOL(phy_sfp_probe);
 
-static bool phy_drv_supports_irq(struct phy_driver *phydrv)
+static bool phy_drv_supports_irq(const struct phy_driver *phydrv)
 {
 	return phydrv->config_intr && phydrv->handle_interrupt;
 }
@@ -1867,7 +1867,7 @@ int phy_suspend(struct phy_device *phydev)
 {
 	struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
 	struct net_device *netdev = phydev->attached_dev;
-	struct phy_driver *phydrv = phydev->drv;
+	const struct phy_driver *phydrv = phydev->drv;
 	int ret;
 
 	if (phydev->suspended)
@@ -1892,7 +1892,7 @@ EXPORT_SYMBOL(phy_suspend);
 
 int __phy_resume(struct phy_device *phydev)
 {
-	struct phy_driver *phydrv = phydev->drv;
+	const struct phy_driver *phydrv = phydev->drv;
 	int ret;
 
 	lockdep_assert_held(&phydev->lock);
diff --git a/drivers/net/phy/xilinx_gmii2rgmii.c b/drivers/net/phy/xilinx_gmii2rgmii.c
index 7fd9fe6a602b..7b1bc5fcef9b 100644
--- a/drivers/net/phy/xilinx_gmii2rgmii.c
+++ b/drivers/net/phy/xilinx_gmii2rgmii.c
@@ -22,7 +22,7 @@
 
 struct gmii2rgmii {
 	struct phy_device *phy_dev;
-	struct phy_driver *phy_drv;
+	const struct phy_driver *phy_drv;
 	struct phy_driver conv_phy_drv;
 	struct mdio_device *mdio;
 };
diff --git a/include/linux/phy.h b/include/linux/phy.h
index a66f07d3f5f4..ad93f8b1b128 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -638,7 +638,7 @@ struct phy_device {
 
 	/* Information about the PHY type */
 	/* And management functions */
-	struct phy_driver *drv;
+	const struct phy_driver *drv;
 
 	struct device_link *devlink;
 
-- 
2.30.2