package/kernel/mac80211/patches/319-0019-brcmfmac-sdio-shorten-retry-loop-in-brcmf_sdio_kso_c.patch

   1 From 5251b6be8bb5c5675bdf12347c7b83937a5c91e5 Mon Sep 17 00:00:00 2001
   2 From: Arend Van Spriel <arend.vanspriel@broadcom.com>
   3 Date: Mon, 5 Sep 2016 11:42:13 +0100
   4 Subject: [PATCH] brcmfmac: sdio: shorten retry loop in
   5  brcmf_sdio_kso_control()
   6
   7 In brcmf_sdio_kso_control() there is a retry loop as hardware may take
   8 time to settle. However, when the call to brcmf_sdiod_regrb() returns
   9 an error it is due to SDIO access failure and it makes no sense to wait
  10 for hardware to settle. This patch aborts the loop after a number of
  11 subsequent access errors.
  12
  13 Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
  14 Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
  15 Reviewed-by: Franky Lin <franky.lin@broadcom.com>
  16 Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
  17 Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
  18 ---
  19  drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c | 11 +++++++++--
  20  1 file changed, 9 insertions(+), 2 deletions(-)
  21
  22 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
  23 +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
  24 @@ -313,6 +313,7 @@ struct rte_console {
  25
  26  #define KSO_WAIT_US 50
  27  #define MAX_KSO_ATTEMPTS (PMU_MAX_TRANSITION_DLY/KSO_WAIT_US)
  28 +#define BRCMF_SDIO_MAX_ACCESS_ERRORS   5
  29
  30  /*
  31   * Conversion of 802.1D priority to precedence level
  32 @@ -677,6 +678,7 @@ brcmf_sdio_kso_control(struct brcmf_sdio
  33  {
  34         u8 wr_val = 0, rd_val, cmp_val, bmask;
  35         int err = 0;
  36 +       int err_cnt = 0;
  37         int try_cnt = 0;
  38
  39         brcmf_dbg(TRACE, "Enter: on=%d\n", on);
  40 @@ -712,9 +714,14 @@ brcmf_sdio_kso_control(struct brcmf_sdio
  41                  */
  42                 rd_val = brcmf_sdiod_regrb(bus->sdiodev, SBSDIO_FUNC1_SLEEPCSR,
  43                                            &err);
  44 -               if (((rd_val & bmask) == cmp_val) && !err)
  45 +               if (!err) {
  46 +                       if ((rd_val & bmask) == cmp_val)
  47 +                               break;
  48 +                       err_cnt = 0;
  49 +               }
  50 +               /* bail out upon subsequent access errors */
  51 +               if (err && (err_cnt++ > BRCMF_SDIO_MAX_ACCESS_ERRORS))
  52                         break;
  53 -
  54                 udelay(KSO_WAIT_US);
  55                 brcmf_sdiod_regwb(bus->sdiodev, SBSDIO_FUNC1_SLEEPCSR,
  56                                   wr_val, &err);