net: ipa: introduce sysfs code

Add IPA device attributes to expose information known by the IPA
driver about the hardware and its configuration.

All pointers used to display these attribute values (i.e., IPA
pointer and endpoint pointers) will have been initialized by the
time IPA probe has completed, so they may be safely dereferenced.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 164 insertions, 1 deletions

diff --git a/drivers/net/ipa/Makefile b/drivers/net/ipa/Makefile
index 1efe1a88104b..bd34fce8f6e6 100644
--- a/drivers/net/ipa/Makefile
+++ b/drivers/net/ipa/Makefile
@@ -7,7 +7,8 @@ ipa-y			:=	ipa_main.o ipa_clock.o ipa_reg.o ipa_mem.o \
 				ipa_table.o ipa_interrupt.o gsi.o gsi_trans.o \
 				ipa_gsi.o ipa_smp2p.o ipa_uc.o \
 				ipa_endpoint.o ipa_cmd.o ipa_modem.o \
-				ipa_resource.o ipa_qmi.o ipa_qmi_msg.o
+				ipa_resource.o ipa_qmi.o ipa_qmi_msg.o \
+				ipa_sysfs.o
 
 ipa-y			+=	ipa_data-v3.5.1.o ipa_data-v4.2.o \
 				ipa_data-v4.5.o ipa_data-v4.9.o \
diff --git a/drivers/net/ipa/ipa_main.c b/drivers/net/ipa/ipa_main.c
index cbd39e4667a3..2243e3e5b7ea 100644
--- a/drivers/net/ipa/ipa_main.c
+++ b/drivers/net/ipa/ipa_main.c
@@ -31,6 +31,7 @@
 #include "ipa_uc.h"
 #include "ipa_interrupt.h"
 #include "gsi_trans.h"
+#include "ipa_sysfs.h"
 
 /**
  * DOC: The IP Accelerator
@@ -906,6 +907,13 @@ static const struct dev_pm_ops ipa_pm_ops = {
 	.resume		= ipa_resume,
 };
 
+static const struct attribute_group *ipa_attribute_groups[] = {
+	&ipa_attribute_group,
+	&ipa_feature_attribute_group,
+	&ipa_modem_attribute_group,
+	NULL,
+};
+
 static struct platform_driver ipa_driver = {
 	.probe		= ipa_probe,
 	.remove		= ipa_remove,
@@ -914,6 +922,7 @@ static struct platform_driver ipa_driver = {
 		.name		= "ipa",
 		.pm		= &ipa_pm_ops,
 		.of_match_table	= ipa_match,
+		.dev_groups	= ipa_attribute_groups,
 	},
 };
 
diff --git a/drivers/net/ipa/ipa_sysfs.c b/drivers/net/ipa/ipa_sysfs.c
new file mode 100644
index 000000000000..ff61dbdd70d8
--- /dev/null
+++ b/drivers/net/ipa/ipa_sysfs.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* Copyright (C) 2021 Linaro Ltd. */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/sysfs.h>
+
+#include "ipa.h"
+#include "ipa_version.h"
+#include "ipa_sysfs.h"
+
+static const char *ipa_version_string(struct ipa *ipa)
+{
+	switch (ipa->version) {
+	case IPA_VERSION_3_0:
+		return "3.0";
+	case IPA_VERSION_3_1:
+		return "3.1";
+	case IPA_VERSION_3_5:
+		return "3.5";
+	case IPA_VERSION_3_5_1:
+		return "3.5.1";
+	case IPA_VERSION_4_0:
+		return "4.0";
+	case IPA_VERSION_4_1:
+		return "4.1";
+	case IPA_VERSION_4_2:
+		return "4.2";
+	case IPA_VERSION_4_5:
+		return "4.5";
+	case IPA_VERSION_4_7:
+		return "4.7";
+	case IPA_VERSION_4_9:
+		return "4.9";
+	case IPA_VERSION_4_11:
+		return "4.11";
+	default:
+		return "0.0";	/* Won't happen (checked at probe time) */
+	}
+}
+
+static ssize_t
+version_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct ipa *ipa = dev_get_drvdata(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%s\n", ipa_version_string(ipa));
+}
+
+static DEVICE_ATTR_RO(version);
+
+static struct attribute *ipa_attrs[] = {
+	&dev_attr_version.attr,
+	NULL
+};
+
+const struct attribute_group ipa_attribute_group = {
+	.attrs		= ipa_attrs,
+};
+
+static const char *ipa_offload_string(struct ipa *ipa)
+{
+	return ipa->version < IPA_VERSION_4_5 ? "MAPv4" : "MAPv5";
+}
+
+static ssize_t rx_offload_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct ipa *ipa = dev_get_drvdata(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%s\n", ipa_offload_string(ipa));
+}
+
+static DEVICE_ATTR_RO(rx_offload);
+
+static ssize_t tx_offload_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct ipa *ipa = dev_get_drvdata(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%s\n", ipa_offload_string(ipa));
+}
+
+static DEVICE_ATTR_RO(tx_offload);
+
+static struct attribute *ipa_feature_attrs[] = {
+	&dev_attr_rx_offload.attr,
+	&dev_attr_tx_offload.attr,
+	NULL
+};
+
+const struct attribute_group ipa_feature_attribute_group = {
+	.name		= "feature",
+	.attrs		= ipa_feature_attrs,
+};
+
+static ssize_t
+ipa_endpoint_id_show(struct ipa *ipa, char *buf, enum ipa_endpoint_name name)
+{
+	u32 endpoint_id = ipa->name_map[name]->endpoint_id;
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", endpoint_id);
+}
+
+static ssize_t rx_endpoint_id_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct ipa *ipa = dev_get_drvdata(dev);
+
+	return ipa_endpoint_id_show(ipa, buf, IPA_ENDPOINT_AP_MODEM_RX);
+}
+
+static DEVICE_ATTR_RO(rx_endpoint_id);
+
+static ssize_t tx_endpoint_id_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct ipa *ipa = dev_get_drvdata(dev);
+
+	return ipa_endpoint_id_show(ipa, buf, IPA_ENDPOINT_AP_MODEM_TX);
+}
+
+static DEVICE_ATTR_RO(tx_endpoint_id);
+
+static struct attribute *ipa_modem_attrs[] = {
+	&dev_attr_rx_endpoint_id.attr,
+	&dev_attr_tx_endpoint_id.attr,
+	NULL
+};
+
+const struct attribute_group ipa_modem_attribute_group = {
+	.name		= "modem",
+	.attrs		= ipa_modem_attrs,
+};
diff --git a/drivers/net/ipa/ipa_sysfs.h b/drivers/net/ipa/ipa_sysfs.h
new file mode 100644
index 000000000000..b34e5650bf8c
--- /dev/null
+++ b/drivers/net/ipa/ipa_sysfs.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2019-2021 Linaro Ltd.
+ */
+#ifndef _IPA_SYSFS_H_
+#define _IPA_SYSFS_H_
+
+struct attribute_group;
+
+extern const struct attribute_group ipa_attribute_group;
+extern const struct attribute_group ipa_feature_attribute_group;
+extern const struct attribute_group ipa_modem_attribute_group;
+
+#endif /* _IPA_SYSFS_H_ */
diff --git a/drivers/net/ipa/ipa_version.h b/drivers/net/ipa/ipa_version.h
index ee2b3d02f3cd..6c16c895d842 100644
--- a/drivers/net/ipa/ipa_version.h
+++ b/drivers/net/ipa/ipa_version.h
@@ -21,6 +21,8 @@
  * @IPA_VERSION_4_11:	IPA version 4.11/GSI version 2.11 (2.1.1)
  *
  * Defines the version of IPA (and GSI) hardware present on the platform.
+ * Please update ipa_version_valid() and ipa_version_string() whenever a
+ * new version is added.
  */
 enum ipa_version {
 	IPA_VERSION_3_0,