target/linux/generic/backport-5.4/703-v5.5-0003-net-dsa-bcm_sf2-Add-support-for-optional-reset-contr.patch

   1 From eee87e4377a4b86dc2eea0ade162b0dc33f40576 Mon Sep 17 00:00:00 2001
   2 From: Florian Fainelli <f.fainelli@gmail.com>
   3 Date: Mon, 4 Nov 2019 13:51:39 -0800
   4 Subject: [PATCH] net: dsa: bcm_sf2: Add support for optional reset controller
   5  line
   6
   7 Grab an optional and exclusive reset controller line for the switch and
   8 manage it during probe/remove functions accordingly. For 7278 devices we
   9 change bcm_sf2_sw_rst() to use the reset controller line since the
  10 WATCHDOG_CTRL register does not reset the switch contrary to stated
  11 documentation.
  12
  13 Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
  14 Reviewed-by: Andrew Lunn <andrew@lunn.ch>
  15 Signed-off-by: David S. Miller <davem@davemloft.net>
  16 ---
  17  drivers/net/dsa/bcm_sf2.c | 19 +++++++++++++++++++
  18  drivers/net/dsa/bcm_sf2.h |  3 +++
  19  2 files changed, 22 insertions(+)
  20
  21 --- a/drivers/net/dsa/bcm_sf2.c
  22 +++ b/drivers/net/dsa/bcm_sf2.c
  23 @@ -346,6 +346,18 @@ static int bcm_sf2_sw_rst(struct bcm_sf2
  24  {
  25         unsigned int timeout = 1000;
  26         u32 reg;
  27 +       int ret;
  28 +
  29 +       /* The watchdog reset does not work on 7278, we need to hit the
  30 +        * "external" reset line through the reset controller.
  31 +        */
  32 +       if (priv->type == BCM7278_DEVICE_ID && !IS_ERR(priv->rcdev)) {
  33 +               ret = reset_control_assert(priv->rcdev);
  34 +               if (ret)
  35 +                       return ret;
  36 +
  37 +               return reset_control_deassert(priv->rcdev);
  38 +       }
  39
  40         reg = core_readl(priv, CORE_WATCHDOG_CTRL);
  41         reg |= SOFTWARE_RESET | EN_CHIP_RST | EN_SW_RESET;
  42 @@ -1099,6 +1111,11 @@ static int bcm_sf2_sw_probe(struct platf
  43         priv->core_reg_align = data->core_reg_align;
  44         priv->num_cfp_rules = data->num_cfp_rules;
  45
  46 +       priv->rcdev = devm_reset_control_get_optional_exclusive(&pdev->dev,
  47 +                                                               "switch");
  48 +       if (PTR_ERR(priv->rcdev) == -EPROBE_DEFER)
  49 +               return PTR_ERR(priv->rcdev);
  50 +
  51         /* Auto-detection using standard registers will not work, so
  52          * provide an indication of what kind of device we are for
  53          * b53_common to work with
  54 @@ -1237,6 +1254,8 @@ static int bcm_sf2_sw_remove(struct plat
  55         dsa_unregister_switch(priv->dev->ds);
  56         bcm_sf2_cfp_exit(priv->dev->ds);
  57         bcm_sf2_mdio_unregister(priv);
  58 +       if (priv->type == BCM7278_DEVICE_ID && !IS_ERR(priv->rcdev))
  59 +               reset_control_assert(priv->rcdev);
  60
  61         return 0;
  62  }
  63 --- a/drivers/net/dsa/bcm_sf2.h
  64 +++ b/drivers/net/dsa/bcm_sf2.h
  65 @@ -18,6 +18,7 @@
  66  #include <linux/types.h>
  67  #include <linux/bitops.h>
  68  #include <linux/if_vlan.h>
  69 +#include <linux/reset.h>
  70
  71  #include <net/dsa.h>
  72
  73 @@ -64,6 +65,8 @@ struct bcm_sf2_priv {
  74         void __iomem                    *fcb;
  75         void __iomem                    *acb;
  76
  77 +       struct reset_control            *rcdev;
  78 +
  79         /* Register offsets indirection tables */
  80         u32                             type;
  81         const u16                       *reg_offsets;