spi: make `cs_change_delay` the first user of the `spi_delay` logic

[linux-2.6-microblaze.git] / drivers / spi / spi.c

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7ba981c..b69c140 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1106,19 +1106,14 @@ static void _spi_transfer_delay_ns(u32 ns)
        }
 }
 
-static void _spi_transfer_cs_change_delay(struct spi_message *msg,
-                                         struct spi_transfer *xfer)
+static int _spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer)
 {
-       u32 delay = xfer->cs_change_delay;
-       u32 unit = xfer->cs_change_delay_unit;
+       u32 delay = _delay->value;
+       u32 unit = _delay->unit;
        u32 hz;
 
-       /* return early on "fast" mode - for everything but USECS */
-       if (!delay) {
-               if (unit == SPI_DELAY_UNIT_USECS)
-                       _spi_transfer_delay_ns(10000);
-               return;
-       }
+       if (!delay)
+               return 0;
 
        switch (unit) {
        case SPI_DELAY_UNIT_USECS:
@@ -1127,20 +1122,62 @@ static void _spi_transfer_cs_change_delay(struct spi_message *msg,
        case SPI_DELAY_UNIT_NSECS: /* nothing to do here */
                break;
        case SPI_DELAY_UNIT_SCK:
+               /* clock cycles need to be obtained from spi_transfer */
+               if (!xfer)
+                       return -EINVAL;
                /* if there is no effective speed know, then approximate
                 * by underestimating with half the requested hz
                 */
                hz = xfer->effective_speed_hz ?: xfer->speed_hz / 2;
+               if (!hz)
+                       return -EINVAL;
                delay *= DIV_ROUND_UP(1000000000, hz);
                break;
        default:
+               return -EINVAL;
+       }
+
+       return delay;
+}
+
+int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer)
+{
+       int delay;
+
+       if (!_delay)
+               return -EINVAL;
+
+       delay = _spi_delay_to_ns(_delay, xfer);
+       if (delay < 0)
+               return delay;
+
+       _spi_transfer_delay_ns(delay);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(spi_delay_exec);
+
+static void _spi_transfer_cs_change_delay(struct spi_message *msg,
+                                         struct spi_transfer *xfer)
+{
+       u32 delay = xfer->cs_change_delay.value;
+       u32 unit = xfer->cs_change_delay.unit;
+       int ret;
+
+       /* return early on "fast" mode - for everything but USECS */
+       if (!delay) {
+               if (unit == SPI_DELAY_UNIT_USECS)
+                       _spi_transfer_delay_ns(10000);
+               return;
+       }
+
+       ret = spi_delay_exec(&xfer->cs_change_delay, xfer);
+       if (ret) {
                dev_err_once(&msg->spi->dev,
                             "Use of unsupported delay unit %i, using default of 10us\n",
-                            xfer->cs_change_delay_unit);
-               delay = 10000;
+                            unit);
+               _spi_transfer_delay_ns(10000);
        }
-       /* now sleep for the requested amount of time */
-       _spi_transfer_delay_ns(delay);
 }
 
 /*