phylib: Add device reset GPIO support

The PHY devices sometimes do have their reset signal (maybe even power
supply?) tied to some GPIO and sometimes it also does happen that a boot
loader does not leave it deasserted. So far this issue has been attacked
from (as I believe) a wrong angle: by teaching the MAC driver to manipulate
the GPIO in question; that solution, when applied to the device trees, led
to adding the PHY reset GPIO properties to the MAC device node, with one
exception: Cadence MACB driver which could handle the "reset-gpios" prop
in a PHY device subnode. I believe that the correct approach is to teach
the 'phylib' to get the MDIO device reset GPIO from the device tree node
corresponding to this device -- which this patch is doing...

Note that I had to modify the AT803x PHY driver as it would stop working
otherwise -- it made use of the reset GPIO for its own purposes...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Rob Herring <robh@kernel.org>
[geert: Propagate actual errors from fwnode_get_named_gpiod()]
[geert: Avoid destroying initial setup]
[geert: Consolidate GPIO descriptor acquiring code]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Richard Leitner <richard.leitner@skidata.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sergei Shtylyov
2017-12-04 13:35:05 +01:00
committed by David S. Miller
parent 62b32379fd
commit bafbdd527d
7 changed files with 87 additions and 19 deletions

View File

@@ -854,6 +854,11 @@ int phy_aneg_done(struct phy_device *phydev);
int phy_stop_interrupts(struct phy_device *phydev);
int phy_restart_aneg(struct phy_device *phydev);
static inline void phy_device_reset(struct phy_device *phydev, int value)
{
mdio_device_reset(&phydev->mdio, value);
}
#define phydev_err(_phydev, format, args...) \
dev_err(&_phydev->mdio.dev, format, ##args)