1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
/*
* This file is part of STM32 DAC driver
*
* Copyright (C) 2017, STMicroelectronics - All Rights Reserved
* Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
*
* License type: GPLv2
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* 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 <linux/clk.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#include "stm32-dac-core.h"
/**
* struct stm32_dac_priv - stm32 DAC core private data
* @pclk: peripheral clock common for all DACs
* @rst: peripheral reset control
* @vref: regulator reference
* @common: Common data for all DAC instances
*/
struct stm32_dac_priv {
struct clk *pclk;
struct reset_control *rst;
struct regulator *vref;
struct stm32_dac_common common;
};
/**
* struct stm32_dac_cfg - DAC configuration
* @has_hfsel: DAC has high frequency control
*/
struct stm32_dac_cfg {
bool has_hfsel;
};
static struct stm32_dac_priv *to_stm32_dac_priv(struct stm32_dac_common *com)
{
return container_of(com, struct stm32_dac_priv, common);
}
static const struct regmap_config stm32_dac_regmap_cfg = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = sizeof(u32),
.max_register = 0x3fc,
};
static int stm32_dac_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
const struct stm32_dac_cfg *cfg;
struct stm32_dac_priv *priv;
struct regmap *regmap;
struct resource *res;
void __iomem *mmio;
int ret;
if (!dev->of_node)
return -ENODEV;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
cfg = (const struct stm32_dac_cfg *)
of_match_device(dev->driver->of_match_table, dev)->data;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mmio = devm_ioremap_resource(dev, res);
if (IS_ERR(mmio))
return PTR_ERR(mmio);
regmap = devm_regmap_init_mmio(dev, mmio, &stm32_dac_regmap_cfg);
if (IS_ERR(regmap))
return PTR_ERR(regmap);
priv->common.regmap = regmap;
priv->vref = devm_regulator_get(dev, "vref");
if (IS_ERR(priv->vref)) {
ret = PTR_ERR(priv->vref);
dev_err(dev, "vref get failed, %d\n", ret);
return ret;
}
ret = regulator_enable(priv->vref);
if (ret < 0) {
dev_err(dev, "vref enable failed\n");
return ret;
}
ret = regulator_get_voltage(priv->vref);
if (ret < 0) {
dev_err(dev, "vref get voltage failed, %d\n", ret);
goto err_vref;
}
priv->common.vref_mv = ret / 1000;
dev_dbg(dev, "vref+=%dmV\n", priv->common.vref_mv);
priv->pclk = devm_clk_get(dev, "pclk");
if (IS_ERR(priv->pclk)) {
ret = PTR_ERR(priv->pclk);
dev_err(dev, "pclk get failed\n");
goto err_vref;
}
ret = clk_prepare_enable(priv->pclk);
if (ret < 0) {
dev_err(dev, "pclk enable failed\n");
goto err_vref;
}
priv->rst = devm_reset_control_get_exclusive(dev, NULL);
if (!IS_ERR(priv->rst)) {
reset_control_assert(priv->rst);
udelay(2);
reset_control_deassert(priv->rst);
}
if (cfg && cfg->has_hfsel) {
/* When clock speed is higher than 80MHz, set HFSEL */
priv->common.hfsel = (clk_get_rate(priv->pclk) > 80000000UL);
ret = regmap_update_bits(regmap, STM32_DAC_CR,
STM32H7_DAC_CR_HFSEL,
priv->common.hfsel ?
STM32H7_DAC_CR_HFSEL : 0);
if (ret)
goto err_pclk;
}
platform_set_drvdata(pdev, &priv->common);
ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, dev);
if (ret < 0) {
dev_err(dev, "failed to populate DT children\n");
goto err_pclk;
}
return 0;
err_pclk:
clk_disable_unprepare(priv->pclk);
err_vref:
regulator_disable(priv->vref);
return ret;
}
static int stm32_dac_remove(struct platform_device *pdev)
{
struct stm32_dac_common *common = platform_get_drvdata(pdev);
struct stm32_dac_priv *priv = to_stm32_dac_priv(common);
of_platform_depopulate(&pdev->dev);
clk_disable_unprepare(priv->pclk);
regulator_disable(priv->vref);
return 0;
}
static const struct stm32_dac_cfg stm32h7_dac_cfg = {
.has_hfsel = true,
};
static const struct of_device_id stm32_dac_of_match[] = {
{
.compatible = "st,stm32f4-dac-core",
}, {
.compatible = "st,stm32h7-dac-core",
.data = (void *)&stm32h7_dac_cfg,
},
{},
};
MODULE_DEVICE_TABLE(of, stm32_dac_of_match);
static struct platform_driver stm32_dac_driver = {
.probe = stm32_dac_probe,
.remove = stm32_dac_remove,
.driver = {
.name = "stm32-dac-core",
.of_match_table = stm32_dac_of_match,
},
};
module_platform_driver(stm32_dac_driver);
MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
MODULE_DESCRIPTION("STMicroelectronics STM32 DAC core driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:stm32-dac-core");
|
