2 * QTest i.MX I2C driver
4 * Copyright (c) 2013 Jean-Christophe Dubois
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, see <http://www.gnu.org/licenses/>.
20 #include "qemu/osdep.h"
21 #include "libqos/i2c.h"
27 #include "hw/i2c/imx_i2c.h"
29 enum IMXI2CDirection {
34 typedef struct IMXI2C {
41 static void imx_i2c_set_slave_addr(IMXI2C *s, uint8_t addr,
42 enum IMXI2CDirection direction)
44 writeb(s->addr + I2DR_ADDR, (addr << 1) |
45 (direction == IMX_I2C_READ ? 1 : 0));
48 static void imx_i2c_send(I2CAdapter *i2c, uint8_t addr,
49 const uint8_t *buf, uint16_t len)
51 IMXI2C *s = (IMXI2C *)i2c;
60 /* set the bus for write */
67 writeb(s->addr + I2CR_ADDR, data);
68 status = readb(s->addr + I2SR_ADDR);
69 g_assert((status & I2SR_IBB) != 0);
71 /* set the slave address */
72 imx_i2c_set_slave_addr(s, addr, IMX_I2C_WRITE);
73 status = readb(s->addr + I2SR_ADDR);
74 g_assert((status & I2SR_IIF) != 0);
75 g_assert((status & I2SR_RXAK) == 0);
77 /* ack the interrupt */
78 writeb(s->addr + I2SR_ADDR, 0);
79 status = readb(s->addr + I2SR_ADDR);
80 g_assert((status & I2SR_IIF) == 0);
83 /* check we are still busy */
84 status = readb(s->addr + I2SR_ADDR);
85 g_assert((status & I2SR_IBB) != 0);
88 writeb(s->addr + I2DR_ADDR, buf[size]);
89 status = readb(s->addr + I2SR_ADDR);
90 g_assert((status & I2SR_IIF) != 0);
91 g_assert((status & I2SR_RXAK) == 0);
93 /* ack the interrupt */
94 writeb(s->addr + I2SR_ADDR, 0);
95 status = readb(s->addr + I2SR_ADDR);
96 g_assert((status & I2SR_IIF) == 0);
101 /* release the bus */
102 data &= ~(I2CR_MSTA | I2CR_MTX);
103 writeb(s->addr + I2CR_ADDR, data);
104 status = readb(s->addr + I2SR_ADDR);
105 g_assert((status & I2SR_IBB) == 0);
108 static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
109 uint8_t *buf, uint16_t len)
111 IMXI2C *s = (IMXI2C *)i2c;
120 /* set the bus for write */
127 writeb(s->addr + I2CR_ADDR, data);
128 status = readb(s->addr + I2SR_ADDR);
129 g_assert((status & I2SR_IBB) != 0);
131 /* set the slave address */
132 imx_i2c_set_slave_addr(s, addr, IMX_I2C_READ);
133 status = readb(s->addr + I2SR_ADDR);
134 g_assert((status & I2SR_IIF) != 0);
135 g_assert((status & I2SR_RXAK) == 0);
137 /* ack the interrupt */
138 writeb(s->addr + I2SR_ADDR, 0);
139 status = readb(s->addr + I2SR_ADDR);
140 g_assert((status & I2SR_IIF) == 0);
142 /* set the bus for read */
144 /* if only one byte don't ack */
148 writeb(s->addr + I2CR_ADDR, data);
149 status = readb(s->addr + I2SR_ADDR);
150 g_assert((status & I2SR_IBB) != 0);
153 readb(s->addr + I2DR_ADDR);
154 status = readb(s->addr + I2SR_ADDR);
155 g_assert((status & I2SR_IIF) != 0);
157 /* ack the interrupt */
158 writeb(s->addr + I2SR_ADDR, 0);
159 status = readb(s->addr + I2SR_ADDR);
160 g_assert((status & I2SR_IIF) == 0);
163 /* check we are still busy */
164 status = readb(s->addr + I2SR_ADDR);
165 g_assert((status & I2SR_IBB) != 0);
167 if (size == (len - 1)) {
168 /* stop the read transaction */
169 data &= ~(I2CR_MSTA | I2CR_MTX);
171 /* ack the data read */
174 writeb(s->addr + I2CR_ADDR, data);
177 buf[size] = readb(s->addr + I2DR_ADDR);
179 if (size != (len - 1)) {
180 status = readb(s->addr + I2SR_ADDR);
181 g_assert((status & I2SR_IIF) != 0);
183 /* ack the interrupt */
184 writeb(s->addr + I2SR_ADDR, 0);
187 status = readb(s->addr + I2SR_ADDR);
188 g_assert((status & I2SR_IIF) == 0);
193 status = readb(s->addr + I2SR_ADDR);
194 g_assert((status & I2SR_IBB) == 0);
197 I2CAdapter *imx_i2c_create(uint64_t addr)
199 IMXI2C *s = g_malloc0(sizeof(*s));
200 I2CAdapter *i2c = (I2CAdapter *)s;
204 i2c->send = imx_i2c_send;
205 i2c->recv = imx_i2c_recv;