2 * Helper module for board specific I2C bus registration
4 * Copyright (C) 2009 Nokia Corporation.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * version 2 as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
24 #include <plat/omap_hwmod.h>
28 /* In register I2C_CON, Bit 15 is the I2C enable bit */
29 #define I2C_EN BIT(15)
30 #define OMAP2_I2C_CON_OFFSET 0x24
31 #define OMAP4_I2C_CON_OFFSET 0xA4
33 /* Maximum microseconds to wait for OMAP module to softreset */
34 #define MAX_MODULE_SOFTRESET_WAIT 10000
36 void __init omap2_i2c_mux_pins(int bus_id)
38 char mux_name[sizeof("i2c2_scl.i2c2_scl")];
40 /* First I2C bus is not muxable */
44 sprintf(mux_name, "i2c%i_scl.i2c%i_scl", bus_id, bus_id);
45 omap_mux_init_signal(mux_name, OMAP_PIN_INPUT);
46 sprintf(mux_name, "i2c%i_sda.i2c%i_sda", bus_id, bus_id);
47 omap_mux_init_signal(mux_name, OMAP_PIN_INPUT);
51 * omap_i2c_reset - reset the omap i2c module.
52 * @oh: struct omap_hwmod *
54 * The i2c moudle in omap2, omap3 had a special sequence to reset. The
57 * - Write to SOFTRESET bit.
59 * - Poll on the RESETDONE bit.
60 * The sequence is implemented in below function. This is called for 2420,
63 int omap_i2c_reset(struct omap_hwmod *oh)
69 if (oh->class->rev == OMAP_I2C_IP_VERSION_2) {
70 i2c_con = OMAP4_I2C_CON_OFFSET;
71 } else if (oh->class->rev == OMAP_I2C_IP_VERSION_1) {
72 i2c_con = OMAP2_I2C_CON_OFFSET;
74 WARN(1, "Cannot reset I2C block %s: unsupported revision\n",
80 v = omap_hwmod_read(oh, i2c_con);
82 omap_hwmod_write(v, oh, i2c_con);
84 /* Write to the SOFTRESET bit */
85 omap_hwmod_softreset(oh);
88 v = omap_hwmod_read(oh, i2c_con);
90 omap_hwmod_write(v, oh, i2c_con);
92 /* Poll on RESETDONE bit */
93 omap_test_timeout((omap_hwmod_read(oh,
94 oh->class->sysc->syss_offs)
95 & SYSS_RESETDONE_MASK),
96 MAX_MODULE_SOFTRESET_WAIT, c);
98 if (c == MAX_MODULE_SOFTRESET_WAIT)
99 pr_warning("%s: %s: softreset failed (waited %d usec)\n",
100 __func__, oh->name, MAX_MODULE_SOFTRESET_WAIT);
102 pr_debug("%s: %s: softreset in %d usec\n", __func__,