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 sysfs for properties reflects the MIPI description as given
  13  * in the MIPI DisCo spec
  14  *
  15  * Base file is:
  16  *      sdw-master-N
  17  *      |---- revision
  18  *      |---- clk_stop_modes
  19  *      |---- max_clk_freq
  20  *      |---- clk_freq
  21  *      |---- clk_gears
  22  *      |---- default_row
  23  *      |---- default_col
  24  *      |---- dynamic_shape
  25  *      |---- err_threshold
  26  */
  27
  28 #define sdw_master_attr(field, format_string)                           \
  29 static ssize_t field##_show(struct device *dev,                         \
  30                             struct device_attribute *attr,              \
  31                             char *buf)                                  \
  32 {                                                                       \
  33         struct sdw_master_device *md = dev_to_sdw_master_device(dev);   \
  34         return sprintf(buf, format_string, md->bus->prop.field);        \
  35 }                                                                       \
  36 static DEVICE_ATTR_RO(field)
  37
  38 sdw_master_attr(revision, "0x%x\n");
  39 sdw_master_attr(clk_stop_modes, "0x%x\n");
  40 sdw_master_attr(max_clk_freq, "%d\n");
  41 sdw_master_attr(default_row, "%d\n");
  42 sdw_master_attr(default_col, "%d\n");
  43 sdw_master_attr(default_frame_rate, "%d\n");
  44 sdw_master_attr(dynamic_frame, "%d\n");
  45 sdw_master_attr(err_threshold, "%d\n");
  46
  47 static ssize_t clock_frequencies_show(struct device *dev,
  48                                       struct device_attribute *attr, char *buf)
  49 {
  50         struct sdw_master_device *md = dev_to_sdw_master_device(dev);
  51         ssize_t size = 0;
  52         int i;
  53
  54         for (i = 0; i < md->bus->prop.num_clk_freq; i++)
  55                 size += sprintf(buf + size, "%8d ",
  56                                 md->bus->prop.clk_freq[i]);
  57         size += sprintf(buf + size, "\n");
  58
  59         return size;
  60 }
  61 static DEVICE_ATTR_RO(clock_frequencies);
  62
  63 static ssize_t clock_gears_show(struct device *dev,
  64                                 struct device_attribute *attr, char *buf)
  65 {
  66         struct sdw_master_device *md = dev_to_sdw_master_device(dev);
  67         ssize_t size = 0;
  68         int i;
  69
  70         for (i = 0; i < md->bus->prop.num_clk_gears; i++)
  71                 size += sprintf(buf + size, "%8d ",
  72                                 md->bus->prop.clk_gears[i]);
  73         size += sprintf(buf + size, "\n");
  74
  75         return size;
  76 }
  77 static DEVICE_ATTR_RO(clock_gears);
  78
  79 static struct attribute *master_node_attrs[] = {
  80         &dev_attr_revision.attr,
  81         &dev_attr_clk_stop_modes.attr,
  82         &dev_attr_max_clk_freq.attr,
  83         &dev_attr_default_row.attr,
  84         &dev_attr_default_col.attr,
  85         &dev_attr_default_frame_rate.attr,
  86         &dev_attr_dynamic_frame.attr,
  87         &dev_attr_err_threshold.attr,
  88         &dev_attr_clock_frequencies.attr,
  89         &dev_attr_clock_gears.attr,
  90         NULL,
  91 };
  92 ATTRIBUTE_GROUPS(master_node);
  93
  94 static void sdw_master_device_release(struct device *dev)
  95 {
  96         struct sdw_master_device *md = dev_to_sdw_master_device(dev);
  97
  98         kfree(md);
  99 }
 100
 101 static const struct dev_pm_ops master_dev_pm = {
 102         SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend,
 103                            pm_generic_runtime_resume, NULL)
 104 };
 105
 106 struct device_type sdw_master_type = {
 107         .name =         "soundwire_master",
 108         .release =      sdw_master_device_release,
 109         .pm = &master_dev_pm,
 110 };
 111
 112 /**
 113  * sdw_master_device_add() - create a Linux Master Device representation.
 114  * @bus: SDW bus instance
 115  * @parent: parent device
 116  * @fwnode: firmware node handle
 117  */
 118 int sdw_master_device_add(struct sdw_bus *bus, struct device *parent,
 119                           struct fwnode_handle *fwnode)
 120 {
 121         struct sdw_master_device *md;
 122         int ret;
 123
 124         if (!parent)
 125                 return -EINVAL;
 126
 127         md = kzalloc(sizeof(*md), GFP_KERNEL);
 128         if (!md)
 129                 return -ENOMEM;
 130
 131         md->dev.bus = &sdw_bus_type;
 132         md->dev.type = &sdw_master_type;
 133         md->dev.parent = parent;
 134         md->dev.groups = master_node_groups;
 135         md->dev.of_node = parent->of_node;
 136         md->dev.fwnode = fwnode;
 137         md->dev.dma_mask = parent->dma_mask;
 138
 139         dev_set_name(&md->dev, "sdw-master-%d", bus->id);
 140
 141         ret = device_register(&md->dev);
 142         if (ret) {
 143                 dev_err(parent, "Failed to add master: ret %d\n", ret);
 144                 /*
 145                  * On err, don't free but drop ref as this will be freed
 146                  * when release method is invoked.
 147                  */
 148                 put_device(&md->dev);
 149                 goto device_register_err;
 150         }
 151
 152         /* add shortcuts to improve code readability/compactness */
 153         md->bus = bus;
 154         bus->dev = &md->dev;
 155         bus->md = md;
 156
 157 device_register_err:
 158         return ret;
 159 }
 160
 161 /**
 162  * sdw_master_device_del() - delete a Linux Master Device representation.
 163  * @bus: bus handle
 164  *
 165  * This function is the dual of sdw_master_device_add()
 166  */
 167 int sdw_master_device_del(struct sdw_bus *bus)
 168 {
 169         device_unregister(bus->dev);
 170
 171         return 0;
 172 }