qemu-e2k/tests/libqos/i2c-imx.c

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/*
* QTest i.MX I2C driver
*
* Copyright (c) 2013 Jean-Christophe Dubois
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "libqos/i2c.h"
#include "libqtest.h"
#include "hw/i2c/imx_i2c.h"
enum IMXI2CDirection {
IMX_I2C_READ,
IMX_I2C_WRITE,
};
typedef struct IMXI2C {
I2CAdapter parent;
uint64_t addr;
} IMXI2C;
static void imx_i2c_set_slave_addr(IMXI2C *s, uint8_t addr,
enum IMXI2CDirection direction)
{
writeb(s->addr + I2DR_ADDR, (addr << 1) |
(direction == IMX_I2C_READ ? 1 : 0));
}
static void imx_i2c_send(I2CAdapter *i2c, uint8_t addr,
const uint8_t *buf, uint16_t len)
{
IMXI2C *s = (IMXI2C *)i2c;
uint8_t data;
uint8_t status;
uint16_t size = 0;
if (!len) {
return;
}
/* set the bus for write */
data = I2CR_IEN |
I2CR_IIEN |
I2CR_MSTA |
I2CR_MTX |
I2CR_TXAK;
writeb(s->addr + I2CR_ADDR, data);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IBB) != 0);
/* set the slave address */
imx_i2c_set_slave_addr(s, addr, IMX_I2C_WRITE);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) != 0);
g_assert((status & I2SR_RXAK) == 0);
/* ack the interrupt */
writeb(s->addr + I2SR_ADDR, 0);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) == 0);
while (size < len) {
/* check we are still busy */
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IBB) != 0);
/* write the data */
writeb(s->addr + I2DR_ADDR, buf[size]);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) != 0);
g_assert((status & I2SR_RXAK) == 0);
/* ack the interrupt */
writeb(s->addr + I2SR_ADDR, 0);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) == 0);
size++;
}
/* release the bus */
data &= ~(I2CR_MSTA | I2CR_MTX);
writeb(s->addr + I2CR_ADDR, data);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IBB) == 0);
}
static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
uint8_t *buf, uint16_t len)
{
IMXI2C *s = (IMXI2C *)i2c;
uint8_t data;
uint8_t status;
uint16_t size = 0;
if (!len) {
return;
}
/* set the bus for write */
data = I2CR_IEN |
I2CR_IIEN |
I2CR_MSTA |
I2CR_MTX |
I2CR_TXAK;
writeb(s->addr + I2CR_ADDR, data);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IBB) != 0);
/* set the slave address */
imx_i2c_set_slave_addr(s, addr, IMX_I2C_READ);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) != 0);
g_assert((status & I2SR_RXAK) == 0);
/* ack the interrupt */
writeb(s->addr + I2SR_ADDR, 0);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) == 0);
/* set the bus for read */
data &= ~I2CR_MTX;
/* if only one byte don't ack */
if (len != 1) {
data &= ~I2CR_TXAK;
}
writeb(s->addr + I2CR_ADDR, data);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IBB) != 0);
/* dummy read */
readb(s->addr + I2DR_ADDR);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) != 0);
/* ack the interrupt */
writeb(s->addr + I2SR_ADDR, 0);
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) == 0);
while (size < len) {
/* check we are still busy */
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IBB) != 0);
if (size == (len - 1)) {
/* stop the read transaction */
data &= ~(I2CR_MSTA | I2CR_MTX);
} else {
/* ack the data read */
data |= I2CR_TXAK;
}
writeb(s->addr + I2CR_ADDR, data);
/* read the data */
buf[size] = readb(s->addr + I2DR_ADDR);
if (size != (len - 1)) {
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) != 0);
/* ack the interrupt */
writeb(s->addr + I2SR_ADDR, 0);
}
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IIF) == 0);
size++;
}
status = readb(s->addr + I2SR_ADDR);
g_assert((status & I2SR_IBB) == 0);
}
I2CAdapter *imx_i2c_create(uint64_t addr)
{
IMXI2C *s = g_malloc0(sizeof(*s));
I2CAdapter *i2c = (I2CAdapter *)s;
s->addr = addr;
i2c->send = imx_i2c_send;
i2c->recv = imx_i2c_recv;
return i2c;
}