According to spec, the maximum power up time is 35ms.
Please refer to below spec for sd and emmc:
"SD Physical Layer Specification 4.10, chapter 6.4.1.2
Power Up Time of Host."
"JEDEC 4.5.1, chapter 10.3.3 Power supply voltages."
Signed-off-by: Kevin Liu <kl...@marvell.com>
---
drivers/mmc/core/core.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 538c8d9..e8e7a85 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1490,10 +1490,9 @@ static void mmc_power_up(struct mmc_host *host)
__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330);
/*
- * This delay should be sufficient to allow the power supply
- * to reach the minimum voltage.
+ * The maximum power ramp up time is 35ms according to spec.
*/
- mmc_delay(10);
+ mmc_delay(35);
host->ios.clock = host->f_init;
--
1.7.9.5
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