From: "Jan Petrous (OSS)" <jan.petrous@xxxxxxxxxxx>
The helper rgmii_clock() implemented Russel's hint during stmmac
glue driver review:
> We seem to have multiple cases of very similar logic in lots of stmmac
> platform drivers, and I think it's about time we said no more to this.
> So, what I think we should do is as follows:
>
> add the following helper - either in stmmac, or more generically
> (phylib? - in which case its name will need changing.)
>
> static long stmmac_get_rgmii_clock(int speed)
> {
> switch (speed) {
> case SPEED_10:
> return 2500000;
>
> case SPEED_100:
> return 25000000;
>
> case SPEED_1000:
> return 125000000;
>
> default:
> return -ENVAL;
> }
> }
>
> Then, this can become:
>
> long tx_clk_rate;
>
> ...
>
> tx_clk_rate = stmmac_get_rgmii_clock(speed);
> if (tx_clk_rate < 0) {
> dev_err(gmac->dev, "Unsupported/Invalid speed: %d\n", speed);
> return;
> }
>
> ret = clk_set_rate(gmac->tx_clk, tx_clk_rate);
Suggested-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Jan Petrous (OSS) <jan.petrous@xxxxxxxxxxx>
---
include/linux/phy.h | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/include/linux/phy.h b/include/linux/phy.h
index a98bc91a0cde..7f6d9e7533ce 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -298,6 +298,27 @@ static inline const char *phy_modes(phy_interface_t interface)
}
}
+/**
+ * rgmii_clock - map link speed to the clock rate
+ * @speed: link speed value
+ *
+ * Description: maps RGMII supported link speeds
+ * into the clock rates.
+ */
+static inline long rgmii_clock(int speed)
+{
+ switch (speed) {
+ case SPEED_10:
+ return 2500000;
+ case SPEED_100:
+ return 25000000;
+ case SPEED_1000:
+ return 125000000;
+ default:
+ return -EINVAL;
+ }
+}
+
#define PHY_INIT_TIMEOUT 100000
#define PHY_FORCE_TIMEOUT 10
--
2.46.0
