Re: [PATCH net-next v2 04/10] net: dsa: lan9303: Added adjust_link() method

From: Egil Hjelmeland
Date: Thu Jul 27 2017 - 06:46:18 EST


On 26. juli 2017 19:09, Andrew Lunn wrote:
On Tue, Jul 25, 2017 at 06:15:47PM +0200, Egil Hjelmeland wrote:
This makes the driver react to device tree "fixed-link" declaration
on CPU port.

- turn off autonegotiation
- force speed 10 or 100 mb/s
- force duplex mode

Signed-off-by: Egil Hjelmeland <privat@xxxxxxxxxxxxxxxxxx>
---
drivers/net/dsa/lan9303-core.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)

diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c
index 0806a0684d55..be6d78f45a5f 100644
--- a/drivers/net/dsa/lan9303-core.c
+++ b/drivers/net/dsa/lan9303-core.c
@@ -17,6 +17,7 @@
#include <linux/regmap.h>
#include <linux/mutex.h>
#include <linux/mii.h>
+#include <linux/phy.h>
#include "lan9303.h"
@@ -746,6 +747,37 @@ static int lan9303_phy_write(struct dsa_switch *ds, int phy, int regnum,
return chip->ops->phy_write(chip, phy, regnum, val);
}
+static void lan9303_adjust_link(struct dsa_switch *ds, int port,
+ struct phy_device *phydev)
+{
+ struct lan9303 *chip = ds->priv;
+
+ int ctl, res;
+
+ ctl = lan9303_phy_read(ds, port, MII_BMCR);
+
+ if (!phy_is_pseudo_fixed_link(phydev))
+ return;
+

Hi Egil

Maybe do this check before reading MII_BMCR?


OK

+ ctl &= ~BMCR_ANENABLE;

Should this also mask out BMCR_SPEED100 and DUPLEX_FULL? Otherwise how
do you select 10/Half if it is already configured for 100/Full?


Yes you are right. I started out with setting ctl to the fixed default
value, and later changed code to start by reading it from HW.


+ if (phydev->speed == SPEED_100)
+ ctl |= BMCR_SPEED100;
+
+ if (phydev->duplex == DUPLEX_FULL)
+ ctl |= BMCR_FULLDPLX;
+
+ res = lan9303_phy_write(ds, port, MII_BMCR, ctl);
+
+ if (port == chip->phy_addr_sel_strap) {
+ /* Virtual Phy: Remove Turbo 200Mbit mode */
+ lan9303_read(chip->regmap, LAN9303_VIRT_SPECIAL_CTRL, &ctl);
+
+ ctl &= ~(1 << 10); // TURBO BIT

BIT(10), or better still something like BIT(LAN9303_VIRT_SPECIAL_TURBO)


Agree

+ res = regmap_write(chip->regmap,
+ LAN9303_VIRT_SPECIAL_CTRL, ctl);
+ }
+}

Andrew