rockchip: spi: Honour the deactivation delay

[platform/kernel/u-boot.git] / drivers / spi / rk_spi.c

diff --git a/drivers/spi/rk_spi.c b/drivers/spi/rk_spi.c
index 8d64249..15cf0bd 100644 (file)
--- 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)