From: Christian Lamparter <chunkeey@googlemail.com>
To: Joerg Albert <jal2@gmx.de>
Cc: "John W. Linville" <linville@tuxdriver.com>,
"linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
Subject: Re: [PATCH] ar9170: handle overflow in tsf_low register during get_tsf
Date: Tue, 15 Sep 2009 23:00:05 +0200 [thread overview]
Message-ID: <200909152300.06026.chunkeey@googlemail.com> (raw)
In-Reply-To: <4AAFF89D.1000804@gmx.de>
On Tuesday 15 September 2009 22:27:09 Joerg Albert wrote:
> ar9170_op_get_tsf: handle a carry from register TSF_L into TSF_H
> by reading TSF_H twice. We also get rid of the mutex here
> and use read_mreg.
>
> Signed-off-by: Joerg Albert <jal2@gmx.de>
NACK.
don't remove the mutex!
it ensures an exclusive access the driver's data structures
(cmdbuf, [readlen and readbuf]) and synchronous control message transfer.
Regards,
Chr
> ---
> drivers/net/wireless/ath/ar9170/cmd.c | 3 +--
> drivers/net/wireless/ath/ar9170/cmd.h | 1 +
> drivers/net/wireless/ath/ar9170/main.c | 30 +++++++++++++++++-------------
> 3 files changed, 19 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ar9170/cmd.c b/drivers/net/wireless/ath/ar9170/cmd.c
> index f57a620..cf6f5c4 100644
> --- a/drivers/net/wireless/ath/ar9170/cmd.c
> +++ b/drivers/net/wireless/ath/ar9170/cmd.c
> @@ -72,8 +72,7 @@ int ar9170_write_reg(struct ar9170 *ar, const u32 reg, const u32 val)
> return err;
> }
>
> -static int ar9170_read_mreg(struct ar9170 *ar, int nregs,
> - const u32 *regs, u32 *out)
> +int ar9170_read_mreg(struct ar9170 *ar, int nregs, const u32 *regs, u32 *out)
> {
> int i, err;
> __le32 *offs, *res;
> diff --git a/drivers/net/wireless/ath/ar9170/cmd.h b/drivers/net/wireless/ath/ar9170/cmd.h
> index a4f0e50..826c45e 100644
> --- a/drivers/net/wireless/ath/ar9170/cmd.h
> +++ b/drivers/net/wireless/ath/ar9170/cmd.h
> @@ -44,6 +44,7 @@
> int ar9170_write_mem(struct ar9170 *ar, const __le32 *data, size_t len);
> int ar9170_write_reg(struct ar9170 *ar, const u32 reg, const u32 val);
> int ar9170_read_reg(struct ar9170 *ar, u32 reg, u32 *val);
> +int ar9170_read_mreg(struct ar9170 *ar, int nregs, const u32 *regs, u32 *out);
> int ar9170_echo_test(struct ar9170 *ar, u32 v);
>
> /*
> diff --git a/drivers/net/wireless/ath/ar9170/main.c b/drivers/net/wireless/ath/ar9170/main.c
> index c1f8c69..3457cd2 100644
> --- a/drivers/net/wireless/ath/ar9170/main.c
> +++ b/drivers/net/wireless/ath/ar9170/main.c
> @@ -2190,22 +2190,26 @@ static u64 ar9170_op_get_tsf(struct ieee80211_hw *hw)
> {
> struct ar9170 *ar = hw->priv;
> int err;
> - u32 tsf_low;
> - u32 tsf_high;
> u64 tsf;
> +#define NR 3
> + static const u32 addr[NR] = { AR9170_MAC_REG_TSF_H,
> + AR9170_MAC_REG_TSF_L,
> + AR9170_MAC_REG_TSF_H };
> + u32 val[NR];
> + int loops = 0;
> +
> + while (loops++ < 100) {
> + err = ar9170_read_mreg(ar, NR, addr, val);
> + if (WARN_ON(err))
> + return 0;
> + if (val[0] == val[2])
> + break;
> + }
>
> - mutex_lock(&ar->mutex);
> - err = ar9170_read_reg(ar, AR9170_MAC_REG_TSF_L, &tsf_low);
> - if (!err)
> - err = ar9170_read_reg(ar, AR9170_MAC_REG_TSF_H, &tsf_high);
> - mutex_unlock(&ar->mutex);
> -
> - if (WARN_ON(err))
> - return 0;
> -
> - tsf = tsf_high;
> - tsf = (tsf << 32) | tsf_low;
> + tsf = val[0];
> + tsf = (tsf << 32) | val[1];
> return tsf;
> +#undef NR
> }
>
> static int ar9170_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
>
next prev parent reply other threads:[~2009-09-15 21:00 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-15 20:27 [PATCH] ar9170: handle overflow in tsf_low register during get_tsf Joerg Albert
2009-09-15 21:00 ` Christian Lamparter [this message]
2009-09-15 21:27 ` [PATCH v2] " Joerg Albert
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