target/linux/ath79/patches-6.6/721-phy-mdio-bitbang-prevent-rescheduling-during-command.patch

   1 From 66e584435ac0de6e0abeb6d7166fe4fe25d6bb73 Mon Sep 17 00:00:00 2001
   2 From: Jonas Gorski <jogo@openwrt.org>
   3 Date: Tue, 16 Jun 2015 13:15:08 +0200
   4 Subject: [PATCH] phy/mdio-bitbang: prevent rescheduling during command
   5
   6 It seems some phys have some maximum timings for accessing the MDIO line,
   7 resulting in bit errors under cpu stress. Prevent this from happening by
   8 disabling interrupts when sending commands.
   9
  10 Signed-off-by: Jonas Gorski <jogo@openwrt.org>
  11 ---
  12  drivers/net/mdio/mdio-bitbang.c | 9 +++++++++
  13  1 file changed, 9 insertions(+)
  14
  15 --- a/drivers/net/mdio/mdio-bitbang.c
  16 +++ b/drivers/net/mdio/mdio-bitbang.c
  17 @@ -14,6 +14,7 @@
  18   * Vitaly Bordug <vbordug@ru.mvista.com>
  19   */
  20
  21 +#include <linux/irqflags.h>
  22  #include <linux/delay.h>
  23  #include <linux/mdio-bitbang.h>
  24  #include <linux/module.h>
  25 @@ -161,22 +162,32 @@ static int mdiobb_read_common(struct mii
  26
  27  int mdiobb_read_c22(struct mii_bus *bus, int phy, int reg)
  28  {
  29 +       int ret;
  30 +       unsigned long flags;
  31         struct mdiobb_ctrl *ctrl = bus->priv;
  32
  33 +       local_irq_save(flags);
  34         mdiobb_cmd(ctrl, ctrl->op_c22_read, phy, reg);
  35
  36 -       return mdiobb_read_common(bus, phy);
  37 +       ret = mdiobb_read_common(bus, phy);
  38 +       local_irq_restore(flags);
  39 +       return ret;
  40  }
  41  EXPORT_SYMBOL(mdiobb_read_c22);
  42
  43  int mdiobb_read_c45(struct mii_bus *bus, int phy, int devad, int reg)
  44  {
  45 +       int ret;
  46 +       unsigned long flags;
  47         struct mdiobb_ctrl *ctrl = bus->priv;
  48
  49 +       local_irq_save(flags);
  50         mdiobb_cmd_addr(ctrl, phy, devad, reg);
  51         mdiobb_cmd(ctrl, MDIO_C45_READ, phy, devad);
  52
  53 -       return mdiobb_read_common(bus, phy);
  54 +       ret = mdiobb_read_common(bus, phy);
  55 +       local_irq_restore(flags);
  56 +       return ret;
  57  }
  58  EXPORT_SYMBOL(mdiobb_read_c45);
  59
  60 @@ -197,22 +208,32 @@ static int mdiobb_write_common(struct mi
  61
  62  int mdiobb_write_c22(struct mii_bus *bus, int phy, int reg, u16 val)
  63  {
  64 +       int ret;
  65 +       unsigned long flags;
  66         struct mdiobb_ctrl *ctrl = bus->priv;
  67
  68 +       local_irq_save(flags);
  69         mdiobb_cmd(ctrl, ctrl->op_c22_write, phy, reg);
  70
  71 -       return mdiobb_write_common(bus, val);
  72 +       ret = mdiobb_write_common(bus, val);
  73 +       local_irq_restore(flags);
  74 +       return ret;
  75  }
  76  EXPORT_SYMBOL(mdiobb_write_c22);
  77
  78  int mdiobb_write_c45(struct mii_bus *bus, int phy, int devad, int reg, u16 val)
  79  {
  80 +       int ret;
  81 +       unsigned long flags;
  82         struct mdiobb_ctrl *ctrl = bus->priv;
  83
  84 +       local_irq_save(flags);
  85         mdiobb_cmd_addr(ctrl, phy, devad, reg);
  86         mdiobb_cmd(ctrl, MDIO_C45_WRITE, phy, devad);
  87
  88 -       return mdiobb_write_common(bus, val);
  89 +       ret = mdiobb_write_common(bus, val);
  90 +       local_irq_restore(flags);
  91 +       return ret;
  92  }
  93  EXPORT_SYMBOL(mdiobb_write_c45);
  94