34 lines
1.4 KiB
C
34 lines
1.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __MACH_SPI_H_
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#define __MACH_SPI_H_
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/*
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* struct spi_imx_master - device.platform_data for SPI controller devices.
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* @chipselect: Array of chipselects for this master or NULL. Numbers >= 0
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* mean GPIO pins, -ENOENT means internal CSPI chipselect
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* matching the position in the array. E.g., if chipselect[1] =
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* -ENOENT then a SPI slave using chip select 1 will use the
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* native SS1 line of the CSPI. Omitting the array will use
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* all native chip selects.
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* Normally you want to use gpio based chip selects as the CSPI
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* module tries to be intelligent about when to assert the
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* chipselect: The CSPI module deasserts the chipselect once it
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* runs out of input data. The other problem is that it is not
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* possible to mix between high active and low active chipselects
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* on one single bus using the internal chipselects.
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* Unfortunately, on some SoCs, Freescale decided to put some
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* chipselects on dedicated pins which are not usable as gpios,
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* so we have to support the internal chipselects.
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*
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* @num_chipselect: If @chipselect is specified, ARRAY_SIZE(chipselect),
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* otherwise the number of native chip selects.
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*/
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struct spi_imx_master {
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int *chipselect;
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int num_chipselect;
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};
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#endif /* __MACH_SPI_H_*/
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