tests/libqos/i2c-imx.c

   1 /*
   2  * QTest i.MX I2C driver
   3  *
   4  * Copyright (c) 2013 Jean-Christophe Dubois
   5  *
   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.
  10  *
  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
  14  *  for more details.
  15  *
  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/>.
  18  */
  19
  20 #include "libqos/i2c.h"
  21
  22 #include <glib.h>
  23 #include <string.h>
  24
  25 #include "qemu/osdep.h"
  26 #include "libqtest.h"
  27
  28 #include "hw/i2c/imx_i2c.h"
  29
  30 enum IMXI2CDirection {
  31     IMX_I2C_READ,
  32     IMX_I2C_WRITE,
  33 };
  34
  35 typedef struct IMXI2C {
  36     I2CAdapter parent;
  37
  38     uint64_t addr;
  39 } IMXI2C;
  40
  41
  42 static void imx_i2c_set_slave_addr(IMXI2C *s, uint8_t addr,
  43                                    enum IMXI2CDirection direction)
  44 {
  45     writeb(s->addr + I2DR_ADDR, (addr << 1) |
  46            (direction == IMX_I2C_READ ? 1 : 0));
  47 }
  48
  49 static void imx_i2c_send(I2CAdapter *i2c, uint8_t addr,
  50                          const uint8_t *buf, uint16_t len)
  51 {
  52     IMXI2C *s = (IMXI2C *)i2c;
  53     uint8_t data;
  54     uint8_t status;
  55     uint16_t size = 0;
  56
  57     if (!len) {
  58         return;
  59     }
  60
  61     /* set the bus for write */
  62     data = I2CR_IEN |
  63            I2CR_IIEN |
  64            I2CR_MSTA |
  65            I2CR_MTX |
  66            I2CR_TXAK;
  67
  68     writeb(s->addr + I2CR_ADDR, data);
  69     status = readb(s->addr + I2SR_ADDR);
  70     g_assert((status & I2SR_IBB) != 0);
  71
  72     /* set the slave address */
  73     imx_i2c_set_slave_addr(s, addr, IMX_I2C_WRITE);
  74     status = readb(s->addr + I2SR_ADDR);
  75     g_assert((status & I2SR_IIF) != 0);
  76     g_assert((status & I2SR_RXAK) == 0);
  77
  78     /* ack the interrupt */
  79     writeb(s->addr + I2SR_ADDR, 0);
  80     status = readb(s->addr + I2SR_ADDR);
  81     g_assert((status & I2SR_IIF) == 0);
  82
  83     while (size < len) {
  84         /* check we are still busy */
  85         status = readb(s->addr + I2SR_ADDR);
  86         g_assert((status & I2SR_IBB) != 0);
  87
  88         /* write the data */
  89         writeb(s->addr + I2DR_ADDR, buf[size]);
  90         status = readb(s->addr + I2SR_ADDR);
  91         g_assert((status & I2SR_IIF) != 0);
  92         g_assert((status & I2SR_RXAK) == 0);
  93
  94         /* ack the interrupt */
  95         writeb(s->addr + I2SR_ADDR, 0);
  96         status = readb(s->addr + I2SR_ADDR);
  97         g_assert((status & I2SR_IIF) == 0);
  98
  99         size++;
 100     }
 101
 102     /* release the bus */
 103     data &= ~(I2CR_MSTA | I2CR_MTX);
 104     writeb(s->addr + I2CR_ADDR, data);
 105     status = readb(s->addr + I2SR_ADDR);
 106     g_assert((status & I2SR_IBB) == 0);
 107 }
 108
 109 static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
 110                          uint8_t *buf, uint16_t len)
 111 {
 112     IMXI2C *s = (IMXI2C *)i2c;
 113     uint8_t data;
 114     uint8_t status;
 115     uint16_t size = 0;
 116
 117     if (!len) {
 118         return;
 119     }
 120
 121     /* set the bus for write */
 122     data = I2CR_IEN |
 123            I2CR_IIEN |
 124            I2CR_MSTA |
 125            I2CR_MTX |
 126            I2CR_TXAK;
 127
 128     writeb(s->addr + I2CR_ADDR, data);
 129     status = readb(s->addr + I2SR_ADDR);
 130     g_assert((status & I2SR_IBB) != 0);
 131
 132     /* set the slave address */
 133     imx_i2c_set_slave_addr(s, addr, IMX_I2C_READ);
 134     status = readb(s->addr + I2SR_ADDR);
 135     g_assert((status & I2SR_IIF) != 0);
 136     g_assert((status & I2SR_RXAK) == 0);
 137
 138     /* ack the interrupt */
 139     writeb(s->addr + I2SR_ADDR, 0);
 140     status = readb(s->addr + I2SR_ADDR);
 141     g_assert((status & I2SR_IIF) == 0);
 142
 143     /* set the bus for read */
 144     data &= ~I2CR_MTX;
 145     /* if only one byte don't ack */
 146     if (len != 1) {
 147         data &= ~I2CR_TXAK;
 148     }
 149     writeb(s->addr + I2CR_ADDR, data);
 150     status = readb(s->addr + I2SR_ADDR);
 151     g_assert((status & I2SR_IBB) != 0);
 152
 153     /* dummy read */
 154     readb(s->addr + I2DR_ADDR);
 155     status = readb(s->addr + I2SR_ADDR);
 156     g_assert((status & I2SR_IIF) != 0);
 157
 158     /* ack the interrupt */
 159     writeb(s->addr + I2SR_ADDR, 0);
 160     status = readb(s->addr + I2SR_ADDR);
 161     g_assert((status & I2SR_IIF) == 0);
 162
 163     while (size < len) {
 164         /* check we are still busy */
 165         status = readb(s->addr + I2SR_ADDR);
 166         g_assert((status & I2SR_IBB) != 0);
 167
 168         if (size == (len - 1)) {
 169             /* stop the read transaction */
 170             data &= ~(I2CR_MSTA | I2CR_MTX);
 171         } else {
 172             /* ack the data read */
 173             data |= I2CR_TXAK;
 174         }
 175         writeb(s->addr + I2CR_ADDR, data);
 176
 177         /* read the data */
 178         buf[size] = readb(s->addr + I2DR_ADDR);
 179
 180         if (size != (len - 1)) {
 181             status = readb(s->addr + I2SR_ADDR);
 182             g_assert((status & I2SR_IIF) != 0);
 183
 184             /* ack the interrupt */
 185             writeb(s->addr + I2SR_ADDR, 0);
 186         }
 187
 188         status = readb(s->addr + I2SR_ADDR);
 189         g_assert((status & I2SR_IIF) == 0);
 190
 191         size++;
 192     }
 193
 194     status = readb(s->addr + I2SR_ADDR);
 195     g_assert((status & I2SR_IBB) == 0);
 196 }
 197
 198 I2CAdapter *imx_i2c_create(uint64_t addr)
 199 {
 200     IMXI2C *s = g_malloc0(sizeof(*s));
 201     I2CAdapter *i2c = (I2CAdapter *)s;
 202
 203     s->addr = addr;
 204
 205     i2c->send = imx_i2c_send;
 206     i2c->recv = imx_i2c_recv;
 207
 208     return i2c;
 209 }