linux_dsm_epyc7002/arch/arm/mach-davinci/include/mach/spi.h
Brian Niebuhr 035540f6ea spi: davinci: add additional comments
Add comments describing the platform data members
and per-chip-select SPI configuration structure.

Also, add some comments describing the what happens
during the driver probe.

Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Tested-By: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
2010-11-18 18:38:37 +05:30

85 lines
2.9 KiB
C

/*
* Copyright 2009 Texas Instruments.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef __ARCH_ARM_DAVINCI_SPI_H
#define __ARCH_ARM_DAVINCI_SPI_H
#define SPI_INTERN_CS 0xFF
enum {
SPI_VERSION_1, /* For DM355/DM365/DM6467 */
SPI_VERSION_2, /* For DA8xx */
};
/**
* davinci_spi_platform_data - Platform data for SPI master device on DaVinci
*
* @version: version of the SPI IP. Different DaVinci devices have slightly
* varying versions of the same IP.
* @num_chipselect: number of chipselects supported by this SPI master
* @intr_line: interrupt line used to connect the SPI IP to the ARM interrupt
* controller withn the SoC. Possible values are 0 and 1.
* @chip_sel: list of GPIOs which can act as chip-selects for the SPI.
* SPI_INTERN_CS denotes internal SPI chip-select. Not necessary
* to populate if all chip-selects are internal.
* @cshold_bug: set this to true if the SPI controller on your chip requires
* a write to CSHOLD bit in between transfers (like in DM355).
*/
struct davinci_spi_platform_data {
u8 version;
u8 num_chipselect;
u8 intr_line;
u8 *chip_sel;
bool cshold_bug;
};
/**
* davinci_spi_config - Per-chip-select configuration for SPI slave devices
*
* @wdelay: amount of delay between transmissions. Measured in number of
* SPI module clocks.
* @odd_parity: polarity of parity flag at the end of transmit data stream.
* 0 - odd parity, 1 - even parity.
* @parity_enable: enable transmission of parity at end of each transmit
* data stream.
* @io_type: type of IO transfer. Choose between polled, interrupt and DMA.
* @timer_disable: disable chip-select timers (setup and hold)
* @c2tdelay: chip-select setup time. Measured in number of SPI module clocks.
* @t2cdelay: chip-select hold time. Measured in number of SPI module clocks.
* @t2edelay: transmit data finished to SPI ENAn pin inactive time. Measured
* in number of SPI clocks.
* @c2edelay: chip-select active to SPI ENAn signal active time. Measured in
* number of SPI clocks.
*/
struct davinci_spi_config {
u8 wdelay;
u8 odd_parity;
u8 parity_enable;
#define SPI_IO_TYPE_INTR 0
#define SPI_IO_TYPE_POLL 1
#define SPI_IO_TYPE_DMA 2
u8 io_type;
u8 timer_disable;
u8 c2tdelay;
u8 t2cdelay;
u8 t2edelay;
u8 c2edelay;
};
#endif /* __ARCH_ARM_DAVINCI_SPI_H */