[U-Boot] [PATCH v2 09/22] rockchip: spi: Honour the deactivation delay
Simon Glass
sjg at chromium.org
Sun Nov 13 22:22:03 CET 2016
This is not currently implemented. Add support for this so that the Chrome
OS EC can be used on jerry.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v2: None
drivers/spi/rk_spi.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/spi/rk_spi.c b/drivers/spi/rk_spi.c
index 8d64249..15cf0bd 100644
--- a/drivers/spi/rk_spi.c
+++ b/drivers/spi/rk_spi.c
@@ -110,6 +110,14 @@ static void spi_cs_activate(struct udevice *dev, uint cs)
struct rockchip_spi_priv *priv = dev_get_priv(bus);
struct rockchip_spi *regs = priv->regs;
+ /* If it's too soon to do another transaction, wait */
+ if (plat->deactivate_delay_us && priv->last_transaction_us) {
+ ulong delay_us; /* The delay completed so far */
+ delay_us = timer_get_us() - priv->last_transaction_us;
+ if (delay_us < plat->deactivate_delay_us)
+ udelay(plat->deactivate_delay_us - delay_us);
+ }
+
debug("activate cs%u\n", cs);
writel(1 << cs, ®s->ser);
if (plat->activate_delay_us)
--
2.8.0.rc3.226.g39d4020
More information about the U-Boot
mailing list