Subject: Re: [PATCH] brcmfmac: prevent watchdog from interfering with scanning and connecting

From: "Fu, Zhonghui" <[email-masked]>
Date: Fri, 20 Jun 2014 00:28:06 +0800

On 2014/6/16 16:15, Arend van Spriel wrote:
> On 16-06-14 07:49, Fu, Zhonghui wrote:
>>  From 14485894add32aedacb3e486ebb2cc2b73861abf Mon Sep 17 00:00:00 2001
>> From: Fu zhonghui <[email-masked]>
>> Date: Wed, 11 Jun 2014 11:06:55 +0800
>> Subject: [PATCH] brcmfmac: prevent watchdog from interfering with scanning and connecting
>>
>> Watchdog in brcmfmac driver may make WiFi chip enter sleep mode
>> before completion of scanning or connecting.
>>
>> This will lead to scanning or connecting failure.
>>
>> Increasing temporarily idle-time threshold during scanning or
>> connecting can ensure scanning or connecting success without
>> watchdog interference.
>
> Are you sure you are not having runtime PM enabled. That could be your problem as the host controller code disables sdio irqs. Please see this thread [1]. For our device runtime pm should not be enabled, but I am not sure if that is taken into account in mmc_attach_sdio() (see code below).
I have tried brcmfmac driver with "CONFIG_PM_RUNTIME is not set", and scanning and connecting  always succeeded. This means that CONFIG_PM_RUNTIME should not be set if we use SDIO WiFi device driven by brcmfmac driver, right?

Thanks,
Zhonghui
>
> Gr. AvS
>
> [1] http://www.spinics.net/lists/linux-mmc/msg25978.html
>
> --8<----------------------------------------------------------------
>
>     /*
>      * Enable runtime PM only if supported by host+card+board
>      */
>     if (host->caps & MMC_CAP_POWER_OFF_CARD) {
>         /*
>          * Let runtime PM core know our card is active
>          */
>         err = pm_runtime_set_active(&card->dev);
>         if (err)
>             goto remove;
>
>         /*
>          * Enable runtime PM for this card
>          */
>         pm_runtime_enable(&card->dev);
>     }
>
>> Signed-off-by: Fu zhonghui <[email-masked]>
>> ---
>>   drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c |   18 ++++++++++++++++--
>>   .../net/wireless/brcm80211/brcmfmac/wl_cfg80211.c  |    3 ++-
>>   2 files changed, 18 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
>> index 13c89a0..729deab 100644
>> --- a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
>> +++ b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
>> @@ -34,6 +34,7 @@
>>   #include <linux/vmalloc.h>
>>   #include <linux/platform_data/brcmfmac-sdio.h>
>>   #include <linux/moduleparam.h>
>> +#include <net/cfg80211.h>
>>   #include <asm/unaligned.h>
>>   #include <defs.h>
>>   #include <brcmu_wifi.h>
>> @@ -43,6 +44,10 @@
>>   #include "sdio_host.h"
>>   #include "chip.h"
>>   #include "nvram.h"
>> +#include "dhd.h"
>> +#include "fwil_types.h"
>> +#include "p2p.h"
>> +#include "wl_cfg80211.h"
>>
>>   #define DCMD_RESP_TIMEOUT  2000    /* In milli second */
>>
>> @@ -307,6 +312,7 @@ struct rte_console {
>>                        * when idle
>>                        */
>>   #define BRCMF_IDLE_INTERVAL    1
>> +#define BRCMF_IDLE_INTERVAL_SCANNING_CONNECTING    100
>>
>>   #define KSO_WAIT_US 50
>>   #define MAX_KSO_ATTEMPTS (PMU_MAX_TRANSITION_DLY/KSO_WAIT_US)
>> @@ -3613,9 +3619,9 @@ void brcmf_sdio_isr(struct brcmf_sdio *bus)
>>
>>   static bool brcmf_sdio_bus_watchdog(struct brcmf_sdio *bus)
>>   {
>> -#ifdef DEBUG
>>       struct brcmf_bus *bus_if = dev_get_drvdata(bus->sdiodev->dev);
>> -#endif    /* DEBUG */
>> +    struct brcmf_cfg80211_info *cfg = bus_if->drvr->config;
>> +    struct brcmf_if *ifp = cfg->pub->iflist[0];
>>
>>       brcmf_dbg(TIMER, "Enter\n");
>>
>> @@ -3678,6 +3684,14 @@ static bool brcmf_sdio_bus_watchdog(struct brcmf_sdio *bus)
>>
>>       /* On idle timeout clear activity flag and/or turn off clock */
>>       if ((bus->idletime > 0) && (bus->clkstate == CLK_AVAIL)) {
>> +
>> +        if (test_bit(BRCMF_SCAN_STATUS_BUSY, &cfg->scan_status) ||
>> +            test_bit(BRCMF_VIF_STATUS_CONNECTING, &ifp->vif->sme_state)) {
>> +            bus->idletime = BRCMF_IDLE_INTERVAL_SCANNING_CONNECTING;
>> +        } else {
>> +            bus->idletime = BRCMF_IDLE_INTERVAL;
>> +        }
>> +
>>           if (++bus->idlecount >= bus->idletime) {
>>               bus->idlecount = 0;
>>               if (bus->activity) {
>> diff --git a/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c b/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
>> index be19852..e76517e 100644
>> --- a/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
>> +++ b/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
>> @@ -913,6 +913,8 @@ brcmf_cfg80211_escan(struct wiphy *wiphy, struct brcmf_cfg80211_vif *vif,
>>           return -EAGAIN;
>>       }
>>
>> +    set_bit(BRCMF_SCAN_STATUS_BUSY, &cfg->scan_status);
>> +
>>       /* If scan req comes for p2p0, send it over primary I/F */
>>       if (vif == cfg->p2p.bss_idx[P2PAPI_BSSCFG_DEVICE].vif)
>>           vif = cfg->p2p.bss_idx[P2PAPI_BSSCFG_PRIMARY].vif;
>> @@ -933,7 +935,6 @@ brcmf_cfg80211_escan(struct wiphy *wiphy, struct brcmf_cfg80211_vif *vif,
>>       }
>>
>>       cfg->scan_request = request;
>> -    set_bit(BRCMF_SCAN_STATUS_BUSY, &cfg->scan_status);
>>       if (escan_req) {
>>           cfg->escan_info.run = brcmf_run_escan;
>>           err = brcmf_p2p_scan_prep(wiphy, request, vif);
>> -- 1.7.1
>>
>
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