net: dsa: bcm_sf2: Add support for optional reset controller line

Grab an optional and exclusive reset controller line for the switch and
manage it during probe/remove functions accordingly. For 7278 devices we
change bcm_sf2_sw_rst() to use the reset controller line since the
WATCHDOG_CTRL register does not reset the switch contrary to stated
documentation.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/bcm_sf2.c b/drivers/net/dsa/bcm_sf2.c
index 67125a5..9ce5a0d 100644 (file)
--- a/drivers/net/dsa/bcm_sf2.c
+++ b/drivers/net/dsa/bcm_sf2.c
@@ -350,6 +350,18 @@ static int bcm_sf2_sw_rst(struct bcm_sf2_priv *priv)
 {
        unsigned int timeout = 1000;
        u32 reg;
+       int ret;
+
+       /* The watchdog reset does not work on 7278, we need to hit the
+        * "external" reset line through the reset controller.
+        */
+       if (priv->type == BCM7278_DEVICE_ID && !IS_ERR(priv->rcdev)) {
+               ret = reset_control_assert(priv->rcdev);
+               if (ret)
+                       return ret;
+
+               return reset_control_deassert(priv->rcdev);
+       }
 
        reg = core_readl(priv, CORE_WATCHDOG_CTRL);
        reg |= SOFTWARE_RESET | EN_CHIP_RST | EN_SW_RESET;
@@ -1092,6 +1104,11 @@ static int bcm_sf2_sw_probe(struct platform_device *pdev)
        priv->core_reg_align = data->core_reg_align;
        priv->num_cfp_rules = data->num_cfp_rules;
 
+       priv->rcdev = devm_reset_control_get_optional_exclusive(&pdev->dev,
+                                                               "switch");
+       if (PTR_ERR(priv->rcdev) == -EPROBE_DEFER)
+               return PTR_ERR(priv->rcdev);
+
        /* Auto-detection using standard registers will not work, so
         * provide an indication of what kind of device we are for
         * b53_common to work with
@@ -1224,6 +1241,8 @@ static int bcm_sf2_sw_remove(struct platform_device *pdev)
        /* Disable all ports and interrupts */
        bcm_sf2_sw_suspend(priv->dev->ds);
        bcm_sf2_mdio_unregister(priv);
+       if (priv->type == BCM7278_DEVICE_ID && !IS_ERR(priv->rcdev))
+               reset_control_assert(priv->rcdev);
 
        return 0;
 }

diff --git a/drivers/net/dsa/bcm_sf2.h b/drivers/net/dsa/bcm_sf2.h
index 1df30cc..de386dd 100644 (file)
--- a/drivers/net/dsa/bcm_sf2.h
+++ b/drivers/net/dsa/bcm_sf2.h
@@ -18,6 +18,7 @@
 #include <linux/types.h>
 #include <linux/bitops.h>
 #include <linux/if_vlan.h>
+#include <linux/reset.h>
 
 #include <net/dsa.h>
 
@@ -64,6 +65,8 @@ struct bcm_sf2_priv {
        void __iomem                    *fcb;
        void __iomem                    *acb;
 
+       struct reset_control            *rcdev;
+
        /* Register offsets indirection tables */
        u32                             type;
        const u16                       *reg_offsets;