linux_dsm_epyc7002/drivers/soundwire/sysfs_slave.c
Pierre-Louis Bossart 0173f525b2 soundwire: sysfs: add slave status and device number before probe
The MIPI DisCo device properties that are read by the driver from
platform firmware, or hard-coded in the driver, should only be
provided as sysfs entries when a driver probes successfully.

However the device status and device number is updated even when there
is no driver present, and hence can be updated when a Slave device is
detected on the bus without being described in platform firmware and
without any driver registered/probed.

As suggested by GregKH, the attribute group for Slave status and
device number is is added by default upon device registration.

Credits to Vinod Koul for the status_show() function, shared in a
separate patch and used as is here. The status table was modified to
remove an unnecessary enum and status_show() is handled in a different
group attribute than what was suggested by Vinod.

Tested-by: Srinivas Kandgatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Co-developed-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200924194430.121058-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-09-28 11:17:43 +05:30

271 lines
6.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
// Copyright(c) 2015-2020 Intel Corporation.
#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/soundwire/sdw.h>
#include <linux/soundwire/sdw_type.h>
#include "bus.h"
#include "sysfs_local.h"
/*
* Slave sysfs
*/
/*
* The sysfs for Slave reflects the MIPI description as given
* in the MIPI DisCo spec.
* status and device_number come directly from the MIPI SoundWire
* 1.x specification.
*
* Base file is device
* |---- status
* |---- device_number
* |---- modalias
* |---- dev-properties
* |---- mipi_revision
* |---- wake_capable
* |---- test_mode_capable
* |---- clk_stop_mode1
* |---- simple_clk_stop_capable
* |---- clk_stop_timeout
* |---- ch_prep_timeout
* |---- reset_behave
* |---- high_PHY_capable
* |---- paging_support
* |---- bank_delay_support
* |---- p15_behave
* |---- master_count
* |---- source_ports
* |---- sink_ports
* |---- dp0
* |---- max_word
* |---- min_word
* |---- words
* |---- BRA_flow_controlled
* |---- simple_ch_prep_sm
* |---- imp_def_interrupts
* |---- dpN_<sink/src>
* |---- max_word
* |---- min_word
* |---- words
* |---- type
* |---- max_grouping
* |---- simple_ch_prep_sm
* |---- ch_prep_timeout
* |---- imp_def_interrupts
* |---- min_ch
* |---- max_ch
* |---- channels
* |---- ch_combinations
* |---- max_async_buffer
* |---- block_pack_mode
* |---- port_encoding
*
*/
#define sdw_slave_attr(field, format_string) \
static ssize_t field##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
struct sdw_slave *slave = dev_to_sdw_dev(dev); \
return sprintf(buf, format_string, slave->prop.field); \
} \
static DEVICE_ATTR_RO(field)
sdw_slave_attr(mipi_revision, "0x%x\n");
sdw_slave_attr(wake_capable, "%d\n");
sdw_slave_attr(test_mode_capable, "%d\n");
sdw_slave_attr(clk_stop_mode1, "%d\n");
sdw_slave_attr(simple_clk_stop_capable, "%d\n");
sdw_slave_attr(clk_stop_timeout, "%d\n");
sdw_slave_attr(ch_prep_timeout, "%d\n");
sdw_slave_attr(reset_behave, "%d\n");
sdw_slave_attr(high_PHY_capable, "%d\n");
sdw_slave_attr(paging_support, "%d\n");
sdw_slave_attr(bank_delay_support, "%d\n");
sdw_slave_attr(p15_behave, "%d\n");
sdw_slave_attr(master_count, "%d\n");
sdw_slave_attr(source_ports, "0x%x\n");
sdw_slave_attr(sink_ports, "0x%x\n");
static ssize_t modalias_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct sdw_slave *slave = dev_to_sdw_dev(dev);
return sdw_slave_modalias(slave, buf, 256);
}
static DEVICE_ATTR_RO(modalias);
static struct attribute *slave_attrs[] = {
&dev_attr_modalias.attr,
NULL,
};
ATTRIBUTE_GROUPS(slave);
static struct attribute *slave_dev_attrs[] = {
&dev_attr_mipi_revision.attr,
&dev_attr_wake_capable.attr,
&dev_attr_test_mode_capable.attr,
&dev_attr_clk_stop_mode1.attr,
&dev_attr_simple_clk_stop_capable.attr,
&dev_attr_clk_stop_timeout.attr,
&dev_attr_ch_prep_timeout.attr,
&dev_attr_reset_behave.attr,
&dev_attr_high_PHY_capable.attr,
&dev_attr_paging_support.attr,
&dev_attr_bank_delay_support.attr,
&dev_attr_p15_behave.attr,
&dev_attr_master_count.attr,
&dev_attr_source_ports.attr,
&dev_attr_sink_ports.attr,
NULL,
};
/*
* we don't use ATTRIBUTES_GROUP here since we want to add a subdirectory
* for device-level properties
*/
static struct attribute_group sdw_slave_dev_attr_group = {
.attrs = slave_dev_attrs,
.name = "dev-properties",
};
/*
* DP0 sysfs
*/
#define sdw_dp0_attr(field, format_string) \
static ssize_t field##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
struct sdw_slave *slave = dev_to_sdw_dev(dev); \
return sprintf(buf, format_string, slave->prop.dp0_prop->field);\
} \
static DEVICE_ATTR_RO(field)
sdw_dp0_attr(max_word, "%d\n");
sdw_dp0_attr(min_word, "%d\n");
sdw_dp0_attr(BRA_flow_controlled, "%d\n");
sdw_dp0_attr(simple_ch_prep_sm, "%d\n");
sdw_dp0_attr(imp_def_interrupts, "0x%x\n");
static ssize_t words_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct sdw_slave *slave = dev_to_sdw_dev(dev);
ssize_t size = 0;
int i;
for (i = 0; i < slave->prop.dp0_prop->num_words; i++)
size += sprintf(buf + size, "%d ",
slave->prop.dp0_prop->words[i]);
size += sprintf(buf + size, "\n");
return size;
}
static DEVICE_ATTR_RO(words);
static struct attribute *dp0_attrs[] = {
&dev_attr_max_word.attr,
&dev_attr_min_word.attr,
&dev_attr_words.attr,
&dev_attr_BRA_flow_controlled.attr,
&dev_attr_simple_ch_prep_sm.attr,
&dev_attr_imp_def_interrupts.attr,
NULL,
};
/*
* we don't use ATTRIBUTES_GROUP here since we want to add a subdirectory
* for dp0-level properties
*/
static const struct attribute_group dp0_group = {
.attrs = dp0_attrs,
.name = "dp0",
};
int sdw_slave_sysfs_init(struct sdw_slave *slave)
{
int ret;
ret = devm_device_add_groups(&slave->dev, slave_groups);
if (ret < 0)
return ret;
ret = devm_device_add_group(&slave->dev, &sdw_slave_dev_attr_group);
if (ret < 0)
return ret;
if (slave->prop.dp0_prop) {
ret = devm_device_add_group(&slave->dev, &dp0_group);
if (ret < 0)
return ret;
}
if (slave->prop.source_ports || slave->prop.sink_ports) {
ret = sdw_slave_sysfs_dpn_init(slave);
if (ret < 0)
return ret;
}
return 0;
}
/*
* the status is shown in capital letters for UNATTACHED and RESERVED
* on purpose, to highligh users to the fact that these status values
* are not expected.
*/
static const char *const slave_status[] = {
[SDW_SLAVE_UNATTACHED] = "UNATTACHED",
[SDW_SLAVE_ATTACHED] = "Attached",
[SDW_SLAVE_ALERT] = "Alert",
[SDW_SLAVE_RESERVED] = "RESERVED",
};
static ssize_t status_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct sdw_slave *slave = dev_to_sdw_dev(dev);
return sprintf(buf, "%s\n", slave_status[slave->status]);
}
static DEVICE_ATTR_RO(status);
static ssize_t device_number_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct sdw_slave *slave = dev_to_sdw_dev(dev);
if (slave->status == SDW_SLAVE_UNATTACHED)
return sprintf(buf, "%s", "N/A");
else
return sprintf(buf, "%d", slave->dev_num);
}
static DEVICE_ATTR_RO(device_number);
static struct attribute *slave_status_attrs[] = {
&dev_attr_status.attr,
&dev_attr_device_number.attr,
NULL,
};
/*
* we don't use ATTRIBUTES_GROUP here since the group is used in a
* separate file and can't be handled as a static.
*/
static const struct attribute_group sdw_slave_status_attr_group = {
.attrs = slave_status_attrs,
};
const struct attribute_group *sdw_slave_status_attr_groups[] = {
&sdw_slave_status_attr_group,
NULL
};