diff options
| author | Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> | 2012-06-18 13:13:30 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-07-16 09:04:04 -0700 |
| commit | 084f5074c2d08a343590f386de79fd9ae2406c03 (patch) | |
| tree | 14dadcf9bcdc37a34db8a3ea596213f62946d88c /drivers/net/wireless | |
| parent | d8a7bedebed60ec6366550edccff31f3e8c509a4 (diff) | |
ath9k_hw: avoid possible infinite loop in ar9003_get_pll_sqsum_dvc
commit f18e3c6b67f448ec47b3a5b242789bd3d5644879 upstream.
"ath9k: Fix softlockup in AR9485" with commit id
64bc1239c790e051ff677e023435d770d2ffa174 fixed the reported
issue, yet its better to avoid the possible infinite loop
in ar9003_get_pll_sqsum_dvc by having a timeout as suggested
by ath9k maintainers.
http://www.spinics.net/lists/linux-wireless/msg92126.html.
Based on my testing PLL's locking measurement is done in
~200us (2 iterations).
Cc: Rolf Offermanns <rolf.offermanns@gmx.net>
Cc: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Cc: Senthil Balasubramanian <senthilb@qca.qualcomm.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/wireless')
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/hw.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index fa84e37bf09..0c59778d47b 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -720,13 +720,25 @@ static void ath9k_hw_init_qos(struct ath_hw *ah) u32 ar9003_get_pll_sqsum_dvc(struct ath_hw *ah) { + struct ath_common *common = ath9k_hw_common(ah); + int i = 0; + REG_CLR_BIT(ah, PLL3, PLL3_DO_MEAS_MASK); udelay(100); REG_SET_BIT(ah, PLL3, PLL3_DO_MEAS_MASK); - while ((REG_READ(ah, PLL4) & PLL4_MEAS_DONE) == 0) + while ((REG_READ(ah, PLL4) & PLL4_MEAS_DONE) == 0) { + udelay(100); + if (WARN_ON_ONCE(i >= 100)) { + ath_err(common, "PLL4 meaurement not done\n"); + break; + } + + i++; + } + return (REG_READ(ah, PLL3) & SQSUM_DVC_MASK) >> 3; } EXPORT_SYMBOL(ar9003_get_pll_sqsum_dvc); |