GNU Linux-libre 5.19-rc6-gnu
[releases.git] / drivers / soundwire / master.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright(c) 2019-2020 Intel Corporation.
3
4 #include <linux/device.h>
5 #include <linux/acpi.h>
6 #include <linux/pm_runtime.h>
7 #include <linux/soundwire/sdw.h>
8 #include <linux/soundwire/sdw_type.h>
9 #include "bus.h"
10
11 /*
12  * The 3s value for autosuspend will only be used if there are no
13  * devices physically attached on a bus segment. In practice enabling
14  * the bus operation will result in children devices become active and
15  * the master device will only suspend when all its children are no
16  * longer active.
17  */
18 #define SDW_MASTER_SUSPEND_DELAY_MS 3000
19
20 /*
21  * The sysfs for properties reflects the MIPI description as given
22  * in the MIPI DisCo spec
23  *
24  * Base file is:
25  *      sdw-master-N
26  *      |---- revision
27  *      |---- clk_stop_modes
28  *      |---- max_clk_freq
29  *      |---- clk_freq
30  *      |---- clk_gears
31  *      |---- default_row
32  *      |---- default_col
33  *      |---- dynamic_shape
34  *      |---- err_threshold
35  */
36
37 #define sdw_master_attr(field, format_string)                           \
38 static ssize_t field##_show(struct device *dev,                         \
39                             struct device_attribute *attr,              \
40                             char *buf)                                  \
41 {                                                                       \
42         struct sdw_master_device *md = dev_to_sdw_master_device(dev);   \
43         return sprintf(buf, format_string, md->bus->prop.field);        \
44 }                                                                       \
45 static DEVICE_ATTR_RO(field)
46
47 sdw_master_attr(revision, "0x%x\n");
48 sdw_master_attr(clk_stop_modes, "0x%x\n");
49 sdw_master_attr(max_clk_freq, "%d\n");
50 sdw_master_attr(default_row, "%d\n");
51 sdw_master_attr(default_col, "%d\n");
52 sdw_master_attr(default_frame_rate, "%d\n");
53 sdw_master_attr(dynamic_frame, "%d\n");
54 sdw_master_attr(err_threshold, "%d\n");
55
56 static ssize_t clock_frequencies_show(struct device *dev,
57                                       struct device_attribute *attr, char *buf)
58 {
59         struct sdw_master_device *md = dev_to_sdw_master_device(dev);
60         ssize_t size = 0;
61         int i;
62
63         for (i = 0; i < md->bus->prop.num_clk_freq; i++)
64                 size += sprintf(buf + size, "%8d ",
65                                 md->bus->prop.clk_freq[i]);
66         size += sprintf(buf + size, "\n");
67
68         return size;
69 }
70 static DEVICE_ATTR_RO(clock_frequencies);
71
72 static ssize_t clock_gears_show(struct device *dev,
73                                 struct device_attribute *attr, char *buf)
74 {
75         struct sdw_master_device *md = dev_to_sdw_master_device(dev);
76         ssize_t size = 0;
77         int i;
78
79         for (i = 0; i < md->bus->prop.num_clk_gears; i++)
80                 size += sprintf(buf + size, "%8d ",
81                                 md->bus->prop.clk_gears[i]);
82         size += sprintf(buf + size, "\n");
83
84         return size;
85 }
86 static DEVICE_ATTR_RO(clock_gears);
87
88 static struct attribute *master_node_attrs[] = {
89         &dev_attr_revision.attr,
90         &dev_attr_clk_stop_modes.attr,
91         &dev_attr_max_clk_freq.attr,
92         &dev_attr_default_row.attr,
93         &dev_attr_default_col.attr,
94         &dev_attr_default_frame_rate.attr,
95         &dev_attr_dynamic_frame.attr,
96         &dev_attr_err_threshold.attr,
97         &dev_attr_clock_frequencies.attr,
98         &dev_attr_clock_gears.attr,
99         NULL,
100 };
101 ATTRIBUTE_GROUPS(master_node);
102
103 static void sdw_master_device_release(struct device *dev)
104 {
105         struct sdw_master_device *md = dev_to_sdw_master_device(dev);
106
107         kfree(md);
108 }
109
110 static const struct dev_pm_ops master_dev_pm = {
111         SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend,
112                            pm_generic_runtime_resume, NULL)
113 };
114
115 struct device_type sdw_master_type = {
116         .name =         "soundwire_master",
117         .release =      sdw_master_device_release,
118         .pm = &master_dev_pm,
119 };
120
121 /**
122  * sdw_master_device_add() - create a Linux Master Device representation.
123  * @bus: SDW bus instance
124  * @parent: parent device
125  * @fwnode: firmware node handle
126  */
127 int sdw_master_device_add(struct sdw_bus *bus, struct device *parent,
128                           struct fwnode_handle *fwnode)
129 {
130         struct sdw_master_device *md;
131         int ret;
132
133         if (!parent)
134                 return -EINVAL;
135
136         md = kzalloc(sizeof(*md), GFP_KERNEL);
137         if (!md)
138                 return -ENOMEM;
139
140         md->dev.bus = &sdw_bus_type;
141         md->dev.type = &sdw_master_type;
142         md->dev.parent = parent;
143         md->dev.groups = master_node_groups;
144         md->dev.of_node = parent->of_node;
145         md->dev.fwnode = fwnode;
146         md->dev.dma_mask = parent->dma_mask;
147
148         dev_set_name(&md->dev, "sdw-master-%d", bus->id);
149
150         ret = device_register(&md->dev);
151         if (ret) {
152                 dev_err(parent, "Failed to add master: ret %d\n", ret);
153                 /*
154                  * On err, don't free but drop ref as this will be freed
155                  * when release method is invoked.
156                  */
157                 put_device(&md->dev);
158                 goto device_register_err;
159         }
160
161         /* add shortcuts to improve code readability/compactness */
162         md->bus = bus;
163         bus->dev = &md->dev;
164         bus->md = md;
165
166         pm_runtime_set_autosuspend_delay(&bus->md->dev, SDW_MASTER_SUSPEND_DELAY_MS);
167         pm_runtime_use_autosuspend(&bus->md->dev);
168         pm_runtime_mark_last_busy(&bus->md->dev);
169         pm_runtime_set_active(&bus->md->dev);
170         pm_runtime_enable(&bus->md->dev);
171         pm_runtime_idle(&bus->md->dev);
172 device_register_err:
173         return ret;
174 }
175
176 /**
177  * sdw_master_device_del() - delete a Linux Master Device representation.
178  * @bus: bus handle
179  *
180  * This function is the dual of sdw_master_device_add()
181  */
182 int sdw_master_device_del(struct sdw_bus *bus)
183 {
184         pm_runtime_disable(&bus->md->dev);
185         device_unregister(bus->dev);
186
187         return 0;
188 }