spi: Add AD-FMCOMMS1-EBZ I2C-SPI bridge driver
This patch adds support for the I2C-SPI bridge which can be found on the Analog Devices AD-FMCOMMS1-EBZ board. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Lars-Peter Clausen
Mark Brown
parent
8b17e0559f
commit
b316590043
|
|
@ -384,6 +384,13 @@ config SPI_TXX9
|
|||
help
|
||||
SPI driver for Toshiba TXx9 MIPS SoCs
|
||||
|
||||
config SPI_XCOMM
|
||||
tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
|
||||
depends on I2C
|
||||
help
|
||||
Support for the SPI-I2C bridge found on the Analog Devices
|
||||
AD-FMCOMMS1-EBZ board.
|
||||
|
||||
config SPI_XILINX
|
||||
tristate "Xilinx SPI controller common module"
|
||||
depends on HAS_IOMEM && EXPERIMENTAL
|
||||
|
|
|
|||
|
|
@ -61,5 +61,6 @@ obj-$(CONFIG_SPI_TI_SSP) += spi-ti-ssp.o
|
|||
obj-$(CONFIG_SPI_TLE62X0) += spi-tle62x0.o
|
||||
obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi-topcliff-pch.o
|
||||
obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
|
||||
obj-$(CONFIG_SPI_XCOMM) += spi-xcomm.o
|
||||
obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
|
||||
|
||||
|
|
|
|||
|
|
@ -0,0 +1,276 @@
|
|||
/*
|
||||
* Analog Devices AD-FMCOMMS1-EBZ board I2C-SPI bridge driver
|
||||
*
|
||||
* Copyright 2012 Analog Devices Inc.
|
||||
* Author: Lars-Peter Clausen <lars@metafoo.de>
|
||||
*
|
||||
* Licensed under the GPL-2 or later.
|
||||
*/
|
||||
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/spi/spi.h>
|
||||
#include <asm/unaligned.h>
|
||||
|
||||
#define SPI_XCOMM_SETTINGS_LEN_OFFSET 10
|
||||
#define SPI_XCOMM_SETTINGS_3WIRE BIT(6)
|
||||
#define SPI_XCOMM_SETTINGS_CS_HIGH BIT(5)
|
||||
#define SPI_XCOMM_SETTINGS_SAMPLE_END BIT(4)
|
||||
#define SPI_XCOMM_SETTINGS_CPHA BIT(3)
|
||||
#define SPI_XCOMM_SETTINGS_CPOL BIT(2)
|
||||
#define SPI_XCOMM_SETTINGS_CLOCK_DIV_MASK 0x3
|
||||
#define SPI_XCOMM_SETTINGS_CLOCK_DIV_64 0x2
|
||||
#define SPI_XCOMM_SETTINGS_CLOCK_DIV_16 0x1
|
||||
#define SPI_XCOMM_SETTINGS_CLOCK_DIV_4 0x0
|
||||
|
||||
#define SPI_XCOMM_CMD_UPDATE_CONFIG 0x03
|
||||
#define SPI_XCOMM_CMD_WRITE 0x04
|
||||
|
||||
#define SPI_XCOMM_CLOCK 48000000
|
||||
|
||||
struct spi_xcomm {
|
||||
struct i2c_client *i2c;
|
||||
|
||||
uint16_t settings;
|
||||
uint16_t chipselect;
|
||||
|
||||
unsigned int current_speed;
|
||||
|
||||
uint8_t buf[63];
|
||||
};
|
||||
|
||||
static int spi_xcomm_sync_config(struct spi_xcomm *spi_xcomm, unsigned int len)
|
||||
{
|
||||
uint16_t settings;
|
||||
uint8_t *buf = spi_xcomm->buf;
|
||||
|
||||
settings = spi_xcomm->settings;
|
||||
settings |= len << SPI_XCOMM_SETTINGS_LEN_OFFSET;
|
||||
|
||||
buf[0] = SPI_XCOMM_CMD_UPDATE_CONFIG;
|
||||
put_unaligned_be16(settings, &buf[1]);
|
||||
put_unaligned_be16(spi_xcomm->chipselect, &buf[3]);
|
||||
|
||||
return i2c_master_send(spi_xcomm->i2c, buf, 5);
|
||||
}
|
||||
|
||||
static void spi_xcomm_chipselect(struct spi_xcomm *spi_xcomm,
|
||||
struct spi_device *spi, int is_active)
|
||||
{
|
||||
unsigned long cs = spi->chip_select;
|
||||
uint16_t chipselect = spi_xcomm->chipselect;
|
||||
|
||||
if (is_active)
|
||||
chipselect |= BIT(cs);
|
||||
else
|
||||
chipselect &= ~BIT(cs);
|
||||
|
||||
spi_xcomm->chipselect = chipselect;
|
||||
}
|
||||
|
||||
static int spi_xcomm_setup_transfer(struct spi_xcomm *spi_xcomm,
|
||||
struct spi_device *spi, struct spi_transfer *t, unsigned int *settings)
|
||||
{
|
||||
unsigned int speed;
|
||||
|
||||
if ((t->bits_per_word && t->bits_per_word != 8) || t->len > 62)
|
||||
return -EINVAL;
|
||||
|
||||
speed = t->speed_hz ? t->speed_hz : spi->max_speed_hz;
|
||||
|
||||
if (speed != spi_xcomm->current_speed) {
|
||||
unsigned int divider = DIV_ROUND_UP(SPI_XCOMM_CLOCK, speed);
|
||||
if (divider >= 64)
|
||||
*settings |= SPI_XCOMM_SETTINGS_CLOCK_DIV_64;
|
||||
else if (divider >= 16)
|
||||
*settings |= SPI_XCOMM_SETTINGS_CLOCK_DIV_16;
|
||||
else
|
||||
*settings |= SPI_XCOMM_SETTINGS_CLOCK_DIV_4;
|
||||
|
||||
spi_xcomm->current_speed = speed;
|
||||
}
|
||||
|
||||
if (spi->mode & SPI_CPOL)
|
||||
*settings |= SPI_XCOMM_SETTINGS_CPOL;
|
||||
else
|
||||
*settings &= ~SPI_XCOMM_SETTINGS_CPOL;
|
||||
|
||||
if (spi->mode & SPI_CPHA)
|
||||
*settings &= ~SPI_XCOMM_SETTINGS_CPHA;
|
||||
else
|
||||
*settings |= SPI_XCOMM_SETTINGS_CPHA;
|
||||
|
||||
if (spi->mode & SPI_3WIRE)
|
||||
*settings |= SPI_XCOMM_SETTINGS_3WIRE;
|
||||
else
|
||||
*settings &= ~SPI_XCOMM_SETTINGS_3WIRE;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int spi_xcomm_txrx_bufs(struct spi_xcomm *spi_xcomm,
|
||||
struct spi_device *spi, struct spi_transfer *t)
|
||||
{
|
||||
int ret;
|
||||
|
||||
if (t->tx_buf) {
|
||||
spi_xcomm->buf[0] = SPI_XCOMM_CMD_WRITE;
|
||||
memcpy(spi_xcomm->buf + 1, t->tx_buf, t->len);
|
||||
|
||||
ret = i2c_master_send(spi_xcomm->i2c, spi_xcomm->buf, t->len + 1);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
else if (ret != t->len + 1)
|
||||
return -EIO;
|
||||
} else if (t->rx_buf) {
|
||||
ret = i2c_master_recv(spi_xcomm->i2c, t->rx_buf, t->len);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
else if (ret != t->len)
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
return t->len;
|
||||
}
|
||||
|
||||
static int spi_xcomm_transfer_one(struct spi_master *master,
|
||||
struct spi_message *msg)
|
||||
{
|
||||
struct spi_xcomm *spi_xcomm = spi_master_get_devdata(master);
|
||||
unsigned int settings = spi_xcomm->settings;
|
||||
struct spi_device *spi = msg->spi;
|
||||
unsigned cs_change = 0;
|
||||
struct spi_transfer *t;
|
||||
bool is_first = true;
|
||||
int status = 0;
|
||||
bool is_last;
|
||||
|
||||
is_first = true;
|
||||
|
||||
spi_xcomm_chipselect(spi_xcomm, spi, true);
|
||||
|
||||
list_for_each_entry(t, &msg->transfers, transfer_list) {
|
||||
|
||||
if (!t->tx_buf && !t->rx_buf && t->len) {
|
||||
status = -EINVAL;
|
||||
break;
|
||||
}
|
||||
|
||||
status = spi_xcomm_setup_transfer(spi_xcomm, spi, t, &settings);
|
||||
if (status < 0)
|
||||
break;
|
||||
|
||||
is_last = list_is_last(&t->transfer_list, &msg->transfers);
|
||||
cs_change = t->cs_change;
|
||||
|
||||
if (cs_change ^ is_last)
|
||||
settings |= BIT(5);
|
||||
else
|
||||
settings &= ~BIT(5);
|
||||
|
||||
if (t->rx_buf) {
|
||||
spi_xcomm->settings = settings;
|
||||
status = spi_xcomm_sync_config(spi_xcomm, t->len);
|
||||
if (status < 0)
|
||||
break;
|
||||
} else if (settings != spi_xcomm->settings || is_first) {
|
||||
spi_xcomm->settings = settings;
|
||||
status = spi_xcomm_sync_config(spi_xcomm, 0);
|
||||
if (status < 0)
|
||||
break;
|
||||
}
|
||||
|
||||
if (t->len) {
|
||||
status = spi_xcomm_txrx_bufs(spi_xcomm, spi, t);
|
||||
|
||||
if (status < 0)
|
||||
break;
|
||||
|
||||
if (status > 0)
|
||||
msg->actual_length += status;
|
||||
}
|
||||
status = 0;
|
||||
|
||||
if (t->delay_usecs)
|
||||
udelay(t->delay_usecs);
|
||||
|
||||
is_first = false;
|
||||
}
|
||||
|
||||
if (status != 0 || !cs_change)
|
||||
spi_xcomm_chipselect(spi_xcomm, spi, false);
|
||||
|
||||
msg->status = status;
|
||||
spi_finalize_current_message(master);
|
||||
|
||||
return status;
|
||||
}
|
||||
|
||||
static int spi_xcomm_setup(struct spi_device *spi)
|
||||
{
|
||||
if (spi->bits_per_word != 8)
|
||||
return -EINVAL;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int __devinit spi_xcomm_probe(struct i2c_client *i2c,
|
||||
const struct i2c_device_id *id)
|
||||
{
|
||||
struct spi_xcomm *spi_xcomm;
|
||||
struct spi_master *master;
|
||||
int ret;
|
||||
|
||||
master = spi_alloc_master(&i2c->dev, sizeof(*spi_xcomm));
|
||||
if (!master)
|
||||
return -ENOMEM;
|
||||
|
||||
spi_xcomm = spi_master_get_devdata(master);
|
||||
spi_xcomm->i2c = i2c;
|
||||
|
||||
master->num_chipselect = 16;
|
||||
master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_3WIRE;
|
||||
master->flags = SPI_MASTER_HALF_DUPLEX;
|
||||
master->setup = spi_xcomm_setup;
|
||||
master->transfer_one_message = spi_xcomm_transfer_one;
|
||||
master->dev.of_node = i2c->dev.of_node;
|
||||
i2c_set_clientdata(i2c, master);
|
||||
|
||||
ret = spi_register_master(master);
|
||||
if (ret < 0)
|
||||
spi_master_put(master);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int __devexit spi_xcomm_remove(struct i2c_client *i2c)
|
||||
{
|
||||
struct spi_master *master = i2c_get_clientdata(i2c);
|
||||
|
||||
spi_unregister_master(master);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct i2c_device_id spi_xcomm_ids[] = {
|
||||
{ "spi-xcomm" },
|
||||
{ },
|
||||
};
|
||||
|
||||
static struct i2c_driver spi_xcomm_driver = {
|
||||
.driver = {
|
||||
.name = "spi-xcomm",
|
||||
.owner = THIS_MODULE,
|
||||
},
|
||||
.id_table = spi_xcomm_ids,
|
||||
.probe = spi_xcomm_probe,
|
||||
.remove = __devexit_p(spi_xcomm_remove),
|
||||
};
|
||||
module_i2c_driver(spi_xcomm_driver);
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
|
||||
MODULE_DESCRIPTION("Analog Devices AD-FMCOMMS1-EBZ board I2C-SPI bridge driver");
|
||||
Loading…
Reference in New Issue