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

From: Arend van Spriel <[email-masked]>
Date: Mon, 16 Jun 2014 10:15:24 +0200

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).

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
>