From 1f6b53901f5bffbbb0464c732e83bb2a3a784ff7 Mon Sep 17 00:00:00 2001 From: Alexander Dahl Date: Tue, 25 Jul 2017 14:00:23 +0200 Subject: [PATCH] memory: atmel-ebi: Allow t_DF timings of zero ns As reported in [1] and in [2] it's not possible to set the device tree property 'atmel,smc-tdf-ns' to zero, although the SoC allows a setting of 0ns for the t_DF time. Allow this setting by doing the same thing as in the atmel nand controller driver by setting ncycles to ATMEL_SMC_MODE_TDF_MIN if zero is set in the dts. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2017-March/490966.html [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2017-July/520652.html Suggested-by: Boris Brezillon Signed-off-by: Alexander Dahl Acked-by: Boris Brezillon Signed-off-by: Alexandre Belloni --- drivers/memory/atmel-ebi.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/memory/atmel-ebi.c b/drivers/memory/atmel-ebi.c index 1cf34d24d4e0..f8a01aea422e 100644 --- a/drivers/memory/atmel-ebi.c +++ b/drivers/memory/atmel-ebi.c @@ -120,12 +120,14 @@ static int atmel_ebi_xslate_smc_timings(struct atmel_ebi_dev *ebid, if (!ret) { required = true; ncycles = DIV_ROUND_UP(val, clk_period_ns); - if (ncycles > ATMEL_SMC_MODE_TDF_MAX || - ncycles < ATMEL_SMC_MODE_TDF_MIN) { + if (ncycles > ATMEL_SMC_MODE_TDF_MAX) { ret = -EINVAL; goto out; } + if (ncycles < ATMEL_SMC_MODE_TDF_MIN) + ncycles = ATMEL_SMC_MODE_TDF_MIN; + smcconf->mode |= ATMEL_SMC_MODE_TDF(ncycles); }