net/stmmac: Use clk_prepare_enable and clk_disable_unprepare

This patch fixes an issue introduced by commit ID 6a81c26f
[net/stmmac: remove conditional compilation of clk code], which
switched from the internal stmmac_clk_{en}{dis}able calls to
clk_{en}{dis}able. By this, calling clk_prepare and clk_unprepare
was removed.

clk_{un}prepare is mandatory for platforms using common clock framework.
Since these drivers are used by SPEAr platform, which supports common
clock framework, add clk_{un}prepare() support for them. Otherwise
the clocks are not correctly en-/disabled and ethernet support doesn't
work.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -1066,7 +1066,7 @@ static int stmmac_open(struct net_device *dev)
 	} else
 		priv->tm->enable = 1;
 #endif
-	clk_enable(priv->stmmac_clk);
+	clk_prepare_enable(priv->stmmac_clk);
 
 	stmmac_check_ether_addr(priv);
 
@@ -1188,7 +1188,7 @@ static int stmmac_open(struct net_device *dev)
 	if (priv->phydev)
 		phy_disconnect(priv->phydev);
 
-	clk_disable(priv->stmmac_clk);
+	clk_disable_unprepare(priv->stmmac_clk);
 
 	return ret;
 }
@@ -1246,7 +1246,7 @@ static int stmmac_release(struct net_device *dev)
 #ifdef CONFIG_STMMAC_DEBUG_FS
 	stmmac_exit_fs();
 #endif
-	clk_disable(priv->stmmac_clk);
+	clk_disable_unprepare(priv->stmmac_clk);
 
 	return 0;
 }
@@ -2178,7 +2178,7 @@ int stmmac_suspend(struct net_device *ndev)
 	else {
 		stmmac_set_mac(priv->ioaddr, false);
 		/* Disable clock in case of PWM is off */
-		clk_disable(priv->stmmac_clk);
+		clk_disable_unprepare(priv->stmmac_clk);
 	}
 	spin_unlock_irqrestore(&priv->lock, flags);
 	return 0;
@@ -2203,7 +2203,7 @@ int stmmac_resume(struct net_device *ndev)
 		priv->hw->mac->pmt(priv->ioaddr, 0);
 	else
 		/* enable the clk prevously disabled */
-		clk_enable(priv->stmmac_clk);
+		clk_prepare_enable(priv->stmmac_clk);
 
 	netif_device_attach(ndev);
 

drivers/net/ethernet/stmicro/stmmac/stmmac_timer.c

@@ -97,12 +97,12 @@ static struct clk *timer_clock;
 static void stmmac_tmu_start(unsigned int new_freq)
 {
 	clk_set_rate(timer_clock, new_freq);
-	clk_enable(timer_clock);
+	clk_prepare_enable(timer_clock);
 }
 
 static void stmmac_tmu_stop(void)
 {
-	clk_disable(timer_clock);
+	clk_disable_unprepare(timer_clock);
 }
 
 int stmmac_open_ext_timer(struct net_device *dev, struct stmmac_timer *tm)
@@ -126,7 +126,7 @@ int stmmac_open_ext_timer(struct net_device *dev, struct stmmac_timer *tm)
 
 int stmmac_close_ext_timer(void)
 {
-	clk_disable(timer_clock);
+	clk_disable_unprepare(timer_clock);
 	tmu2_unregister_user();
 	clk_put(timer_clock);
 	return 0;