[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, &regs->ser);
 	if (plat->activate_delay_us)
-- 
2.8.0.rc3.226.g39d4020



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