stmmac: Add an optional register interface clock
The DWMAC block on certain SoCs (such as IMG Pistachio) have a second
clock which must be enabled in order to access the peripheral's
register interface, so add support for requesting and enabling an
optional "pclk".
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: James Hartley <james.hartley@imgtec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 5336594..06103ca 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2849,6 +2849,16 @@
}
clk_prepare_enable(priv->stmmac_clk);
+ priv->pclk = devm_clk_get(priv->device, "pclk");
+ if (IS_ERR(priv->pclk)) {
+ if (PTR_ERR(priv->pclk) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ goto error_pclk_get;
+ }
+ priv->pclk = NULL;
+ }
+ clk_prepare_enable(priv->pclk);
+
priv->stmmac_rst = devm_reset_control_get(priv->device,
STMMAC_RESOURCE_NAME);
if (IS_ERR(priv->stmmac_rst)) {
@@ -2934,6 +2944,8 @@
error_netdev_register:
netif_napi_del(&priv->napi);
error_hw_init:
+ clk_disable_unprepare(priv->pclk);
+error_pclk_get:
clk_disable_unprepare(priv->stmmac_clk);
error_clk_get:
free_netdev(ndev);
@@ -2965,6 +2977,7 @@
unregister_netdev(ndev);
if (priv->stmmac_rst)
reset_control_assert(priv->stmmac_rst);
+ clk_disable_unprepare(priv->pclk);
clk_disable_unprepare(priv->stmmac_clk);
free_netdev(ndev);
@@ -3011,6 +3024,7 @@
stmmac_set_mac(priv->ioaddr, false);
pinctrl_pm_select_sleep_state(priv->device);
/* Disable clock in case of PWM is off */
+ clk_disable(priv->pclk);
clk_disable(priv->stmmac_clk);
}
spin_unlock_irqrestore(&priv->lock, flags);
@@ -3051,6 +3065,7 @@
pinctrl_pm_select_default_state(priv->device);
/* enable the clk prevously disabled */
clk_enable(priv->stmmac_clk);
+ clk_enable(priv->pclk);
/* reset the phy so that it's ready */
if (priv->mii)
stmmac_mdio_reset(priv->mii);