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FMC ADC 100M 14b 4cha - Software
Commit 9eba1441 authored by Federico Vaga's avatar Federico Vaga
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spi: add SPI support 

Signed-off-by: 's avatarFederico Vaga <federico.vaga@gmail.com>
parent 6275c231
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Makefile
View file @ 9eba1441
......@@ -19,6 +19,7 @@ spec-fmc-adc-objs += fa-core.o
spec-fmc-adc-objs += fa-zio-trg.o
spec-fmc-adc-objs += fa-dma.o
spec-fmc-adc-objs += onewire.o
spec-fmc-adc-objs += spi.o
all: modules
......
fa-core.c
View file @ 9eba1441
......@@ -25,6 +25,7 @@ struct fa_modlist {
};
#define SUBSYS(x) { #x, fa_ ## x ## _init, fa_ ## x ## _exit }
static struct fa_modlist mods[] = {
SUBSYS(spi),
SUBSYS(onewire),
SUBSYS(zio),
};
......
fmc-adc.h
View file @ 9eba1441
......@@ -18,6 +18,7 @@
#define FA_CAR_MEM_OFF 0x30000
#define FA_UTC_MEM_OFF 0x40000
#define FA_IRQ_MEM_OFF 0x50000
#define FA_SPI_MEM_OFF 0x70000
#define FA_ADC_MEM_OFF 0x90000
#define FA_OWI_MEM_OFF 0XA0000 /* one-wire */
......@@ -310,6 +311,11 @@ extern void fa_spec_exit(void);
extern int fa_onewire_init(struct fa_dev *fa);
extern void fa_onewire_exit(struct fa_dev *fa);
extern int fa_read_temp(struct fa_dev *fa, int verbose);
/* functions exported by spi.c */
extern int fa_spi_xfer(struct fa_dev *fa, int cs, int num_bits,
uint32_t tx, uint32_t *rx);
extern int fa_spi_init(struct fa_dev *fd);
extern void fa_spi_exit(struct fa_dev *fd);
#endif /* __KERNEL__ */
#endif /* _fa_dev_H_ */
spi.c 0 → 100644
View file @ 9eba1441
/*
* SPI access to fine-delay internals
*
* Copyright (C) 2012 CERN (www.cern.ch)
* Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
* Author: Alessandro Rubini <rubini@gnudd.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* version 2 as published by the Free Software Foundation or, at your
* option, any later version.
*/
#include <linux/jiffies.h>
#include <linux/io.h>
#include <linux/delay.h>
#include "fmc-adc.h"
/* SPI register */
#define FA_SPI_RX(x) (x * 4)
#define FA_SPI_TX(x) (x * 4)
#define FA_SPI_CTRL 0x10
#define FA_SPI_DIV 0x14
#define FA_SPI_CS 0x18
/* SPI control register fields mask */
#define FA_SPI_CTRL_BUF 0x007F
#define FA_SPI_CTRL_BUSY 0x0100
#define FA_SPI_CTRL_Rx_NEG 0x0200
#define FA_SPI_CTRL_Tx_NEG 0x0400
#define FA_SPI_CTRL_LSB 0x0800
#define FA_SPI_CTRL_IE 0x1000
#define FA_SPI_CTRL_ASS 0x2000
int fa_spi_xfer(struct fa_dev *fa, int cs, int num_bits,
uint32_t tx, uint32_t *rx)
{
uint32_t ctrl = 0;
unsigned long j = jiffies + HZ;
int err = 0;
pr_info("%s:%d out %d\n", __func__, __LINE__, tx);
/* Put out value in the T0 register*/
writel((tx & (num_bits-1)), fa->base + FA_SPI_MEM_OFF + FA_SPI_TX(0));
/* Configure SPI controller */
ctrl |= FA_SPI_CTRL_ASS | /* Automatic handle ChipSelect*/
num_bits; /* Transfer num_bits bits */
writel(ctrl, fa->base + FA_SPI_MEM_OFF + FA_SPI_CTRL);
/* Set Chip Select */
writel((1 << cs), fa->base + FA_SPI_MEM_OFF + FA_SPI_CTRL_ASS);
/* Start transfer */
ctrl |= FA_SPI_CTRL_BUSY;
writel(ctrl, fa->base + FA_SPI_MEM_OFF + FA_SPI_CTRL);
/* Wait transfer complete */
pr_info("%s:%d\n", __func__, __LINE__);
while(readl(fa->base + FA_SPI_MEM_OFF + FA_SPI_CTRL) & FA_SPI_CTRL_BUSY) {
pr_info("%s:%d\n", __func__, __LINE__);
if (jiffies > j) {
err = -EIO;
goto out;
}
}
pr_info("%s:%d\n", __func__, __LINE__);
/* Transfer compleate, read data */
*rx = readl(fa->base + FA_SPI_MEM_OFF + FA_SPI_RX(0)) & (num_bits-1);
out:
pr_info("%s:%d in %d\n", __func__, __LINE__, *rx);
/* Clear Chip Select */
writel(0, fa->base + FA_SPI_MEM_OFF + FA_SPI_CTRL_ASS);
return err;
}
int fa_spi_init(struct fa_dev *fa)
{
/* nothing to do */
return 0;
}
void fa_spi_exit(struct fa_dev *fa)
{
/* nothing to do */
}
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