[PATCH net 1/3] net: stmmac: Fallback to Platform Data clock in Watchdog conversion

[Jose Abreu]

If we don't have DT then stmmac_clk will not be available. Let's add a
new Platform Data field so that we can specify the refclk by this mean.

This way we can still use the coalesce command in PCI based setups.

Signed-off-by: Jose Abreu <joab...@synopsys.com>
Cc: Joao Pinto <jpi...@synopsys.com>
Cc: David S. Miller <da...@davemloft.net>
Cc: Giuseppe Cavallaro <peppe.cavall...@st.com>
Cc: Alexandre Torgue <alexandre.tor...@st.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c | 14 ++++++++++----
 include/linux/stmmac.h                               |  1 +
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c 
b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
index d1f61c25d82b..5d85742a2be0 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
@@ -721,8 +721,11 @@ static u32 stmmac_usec2riwt(u32 usec, struct stmmac_priv 
*priv)
 {
        unsigned long clk = clk_get_rate(priv->plat->stmmac_clk);
 
-       if (!clk)
-               return 0;
+       if (!clk) {
+               clk = priv->plat->clk_ref_rate;
+               if (!clk)
+                       return 0;
+       }
 
        return (usec * (clk / 1000000)) / 256;
 }
@@ -731,8 +734,11 @@ static u32 stmmac_riwt2usec(u32 riwt, struct stmmac_priv 
*priv)
 {
        unsigned long clk = clk_get_rate(priv->plat->stmmac_clk);
 
-       if (!clk)
-               return 0;
+       if (!clk) {
+               clk = priv->plat->clk_ref_rate;
+               if (!clk)
+                       return 0;
+       }
 
        return (riwt * 256) / (clk / 1000000);
 }
diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index 7ddfc65586b0..4335bd771ce5 100644
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -184,6 +184,7 @@ struct plat_stmmacenet_data {
        struct clk *pclk;
        struct clk *clk_ptp_ref;
        unsigned int clk_ptp_rate;
+       unsigned int clk_ref_rate;
        struct reset_control *stmmac_rst;
        struct stmmac_axi *axi;
        int has_gmac4;
-- 
2.7.4