1 /*
2 * Copyright (c) 2006-2022, RT-Thread Development Team
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 *
6 * Change Logs:
7 * Date Author Notes
8 * 2022-12-06 GuEe-GUI first version
9 */
10
11 #include <rtdevice.h>
12
13 #define DBG_TAG "dev.i2c.dm"
14 #define DBG_LVL DBG_INFO
15 #include <rtdbg.h>
16
17 #ifdef RT_USING_OFW
i2c_parse_timing(struct rt_ofw_node * dev_np,const char * propname,rt_uint32_t * out_value,rt_uint32_t def_value,rt_bool_t use_defaults)18 static void i2c_parse_timing(struct rt_ofw_node *dev_np, const char *propname,
19 rt_uint32_t *out_value, rt_uint32_t def_value, rt_bool_t use_defaults)
20 {
21 if (rt_ofw_prop_read_u32(dev_np, propname, out_value) && use_defaults)
22 {
23 *out_value = def_value;
24 }
25 }
26
i2c_timings_ofw_parse(struct rt_ofw_node * dev_np,struct i2c_timings * timings,rt_bool_t use_defaults)27 rt_err_t i2c_timings_ofw_parse(struct rt_ofw_node *dev_np, struct i2c_timings *timings,
28 rt_bool_t use_defaults)
29 {
30 rt_ubase_t def;
31 rt_bool_t udef = use_defaults;
32 struct i2c_timings *t = timings;
33
34 i2c_parse_timing(dev_np, "clock-frequency", &t->bus_freq_hz, I2C_MAX_STANDARD_MODE_FREQ, udef);
35
36 def = t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ ? 1000 : t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120;
37 i2c_parse_timing(dev_np, "i2c-scl-rising-time-ns", &t->scl_rise_ns, def, udef);
38
39 def = t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120;
40 i2c_parse_timing(dev_np, "i2c-scl-falling-time-ns", &t->scl_fall_ns, def, udef);
41
42 i2c_parse_timing(dev_np, "i2c-scl-internal-delay-ns", &t->scl_int_delay_ns, 0, udef);
43 i2c_parse_timing(dev_np, "i2c-sda-falling-time-ns", &t->sda_fall_ns, t->scl_fall_ns, udef);
44 i2c_parse_timing(dev_np, "i2c-sda-hold-time-ns", &t->sda_hold_ns, 0, udef);
45 i2c_parse_timing(dev_np, "i2c-digital-filter-width-ns", &t->digital_filter_width_ns, 0, udef);
46 i2c_parse_timing(dev_np, "i2c-analog-filter-cutoff-frequency", &t->analog_filter_cutoff_freq_hz, 0, udef);
47
48 return RT_EOK;
49 }
50 #endif /* RT_USING_OFW */
51