diff options
| author | Faiz Abbas <faiz_abbas@ti.com> | 2019-10-10 16:22:30 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-03-20 11:55:57 +0100 |
| commit | 6bdf6513f33087fb2280c8c40439f362e7ee6fdc (patch) | |
| tree | b11e613090ec54787ab8a7b01aa961e2d35dc9d1 | |
| parent | 3f909e15839c1c9edaa02d061f1198fb24de32ff (diff) | |
mmc: sdhci-omap: Fix Tuning procedure for temperatures < -20C
[ Upstream commit feb40824d78eac5e48f56498dca941754dff33d7 ]
According to the App note[1] detailing the tuning algorithm, for
temperatures < -20C, the initial tuning value should be min(largest value
in LPW - 24, ceil(13/16 ratio of LPW)). The largest value in LPW is
(max_window + 4 * (max_len - 1)) and not (max_window + 4 * max_len) itself.
Fix this implementation.
[1] http://www.ti.com/lit/an/spraca9b/spraca9b.pdf
Fixes: 961de0a856e3 ("mmc: sdhci-omap: Workaround errata regarding SDR104/HS200 tuning failures (i929)")
Cc: stable@vger.kernel.org
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/mmc/host/sdhci-omap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/mmc/host/sdhci-omap.c b/drivers/mmc/host/sdhci-omap.c index 890fcd2fb12d..e9793d8e83a0 100644 --- a/drivers/mmc/host/sdhci-omap.c +++ b/drivers/mmc/host/sdhci-omap.c @@ -387,7 +387,7 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode) * on temperature */ if (temperature < -20000) - phase_delay = min(max_window + 4 * max_len - 24, + phase_delay = min(max_window + 4 * (max_len - 1) - 24, max_window + DIV_ROUND_UP(13 * max_len, 16) * 4); else if (temperature < 20000) |