linux-imx

/*

 * Driver for Broadcom BCM2835 auxiliary SPI Controllers

 *

 * the driver does not rely on the native chipselects at all

 * but only uses the gpio type chipselects

 *

 * Based on: spi-bcm2835.c

 *

 * Copyright (C) 2015 Martin Sperl

 *

 * 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.

 */

​

#include <linux/clk.h>

#include <linux/completion.h>

#include <linux/delay.h>

#include <linux/err.h>

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/of_address.h>

#include <linux/of_device.h>

#include <linux/of_gpio.h>

#include <linux/of_irq.h>

#include <linux/regmap.h>

#include <linux/spi/spi.h>

#include <linux/spinlock.h>

​

/*

 * spi register defines

 *

 * note there is garbage in the "official" documentation,

 * so some data is taken from the file:

 *   brcm_usrlib/dag/vmcsx/vcinclude/bcm2708_chip/aux_io.h

 * inside of:

 *   http://www.broadcom.com/docs/support/videocore/Brcm_Android_ICS_Graphics_Stack.tar.gz

 */

​

/* SPI register offsets */

#define BCM2835_AUX_SPI_CNTL0   0x00

#define BCM2835_AUX_SPI_CNTL1   0x04

#define BCM2835_AUX_SPI_STAT    0x08

#define BCM2835_AUX_SPI_PEEK    0x0C

#define BCM2835_AUX_SPI_IO  0x20

#define BCM2835_AUX_SPI_TXHOLD  0x30

​

/* Bitfields in CNTL0 */

#define BCM2835_AUX_SPI_CNTL0_SPEED 0xFFF00000

#define BCM2835_AUX_SPI_CNTL0_SPEED_MAX 0xFFF

#define BCM2835_AUX_SPI_CNTL0_SPEED_SHIFT   20

#define BCM2835_AUX_SPI_CNTL0_CS    0x000E0000

#define BCM2835_AUX_SPI_CNTL0_POSTINPUT 0x00010000

#define BCM2835_AUX_SPI_CNTL0_VAR_CS    0x00008000