1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef __MACH_SPI_H_
4 #define __MACH_SPI_H_
5 
6 /*
7  * struct spi_imx_master - device.platform_data for SPI controller devices.
8  * @chipselect: Array of chipselects for this master or NULL.  Numbers >= 0
9  *              mean GPIO pins, -ENOENT means internal CSPI chipselect
10  *              matching the position in the array.  E.g., if chipselect[1] =
11  *              -ENOENT then a SPI slave using chip select 1 will use the
12  *              native SS1 line of the CSPI.  Omitting the array will use
13  *              all native chip selects.
14 
15  *              Normally you want to use gpio based chip selects as the CSPI
16  *              module tries to be intelligent about when to assert the
17  *              chipselect:  The CSPI module deasserts the chipselect once it
18  *              runs out of input data.  The other problem is that it is not
19  *              possible to mix between high active and low active chipselects
20  *              on one single bus using the internal chipselects.
21  *              Unfortunately, on some SoCs, Freescale decided to put some
22  *              chipselects on dedicated pins which are not usable as gpios,
23  *              so we have to support the internal chipselects.
24  *
25  * @num_chipselect: If @chipselect is specified, ARRAY_SIZE(chipselect),
26  *                  otherwise the number of native chip selects.
27  */
28 struct spi_imx_master {
29 	int	*chipselect;
30 	int	num_chipselect;
31 };
32 
33 #endif /* __MACH_SPI_H_*/
34