1 files changed, 17 insertions, 12 deletions

diff --git a/include/linux/platform_data/spi-imx.h b/include/linux/platform_data/spi-imx.h
index 6f012fefa1a2..328f670d10bd 100644
--- a/include/linux/platform_data/spi-imx.h
+++ b/include/linux/platform_data/spi-imx.h
@@ -5,24 +5,29 @@
 
 /*
  * struct spi_imx_master - device.platform_data for SPI controller devices.
- * @chipselect: Array of chipselects for this master. Numbers >= 0 mean gpio
- *              pins, numbers < 0 mean internal CSPI chipselects according
- *              to MXC_SPI_CS(). Normally you want to use gpio based chip
- *              selects as the CSPI module tries to be intelligent about
- *              when to assert the chipselect: The CSPI module deasserts the
- *              chipselect once it runs out of input data. The other problem
- *              is that it is not possible to mix between high active and low
- *              active chipselects on one single bus using the internal
- *              chipselects. Unfortunately Freescale decided to put some
+ * @chipselect: Array of chipselects for this master or NULL.  Numbers >= 0
+ *              mean GPIO pins, -ENOENT means internal CSPI chipselect
+ *              matching the position in the array.  E.g., if chipselect[1] =
+ *              -ENOENT then a SPI slave using chip select 1 will use the
+ *              native SS1 line of the CSPI.  Omitting the array will use
+ *              all native chip selects.
+
+ *              Normally you want to use gpio based chip selects as the CSPI
+ *              module tries to be intelligent about when to assert the
+ *              chipselect:  The CSPI module deasserts the chipselect once it
+ *              runs out of input data.  The other problem is that it is not
+ *              possible to mix between high active and low active chipselects
+ *              on one single bus using the internal chipselects.
+ *              Unfortunately, on some SoCs, Freescale decided to put some
  *              chipselects on dedicated pins which are not usable as gpios,
  *              so we have to support the internal chipselects.
- * @num_chipselect: ARRAY_SIZE(chipselect)
+ *
+ * @num_chipselect: If @chipselect is specified, ARRAY_SIZE(chipselect),
+ *                  otherwise the number of native chip selects.
  */
 struct spi_imx_master {
         int     *chipselect;
         int     num_chipselect;
 };
 
-#define MXC_SPI_CS(no)  ((no) - 32)
-
 #endif /* __MACH_SPI_H_*/