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authorBjorn Andersson <bjorn.andersson@sonymobile.com>2015-09-25 01:25:01 (GMT)
committerAndy Gross <agross@codeaurora.org>2015-12-08 19:01:01 (GMT)
commit9460ae2ff3081b43e4f93126cfd26a27cda1b6a1 (patch)
treef199913f7877802c2b2de7dce744417f2db211a1 /drivers/soc
parent8005c49d9aea74d382f474ce11afbbc7d7130bec (diff)
downloadlinux-9460ae2ff3081b43e4f93126cfd26a27cda1b6a1.tar.xz
soc: qcom: Introduce common SMEM state machine code
This implements a common API for handling and exposing SMP2P and SMSM state information. Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> Signed-off-by: Andy Gross <agross@codeaurora.org>
Diffstat (limited to 'drivers/soc')
-rw-r--r--drivers/soc/qcom/Kconfig3
-rw-r--r--drivers/soc/qcom/Makefile1
-rw-r--r--drivers/soc/qcom/smem_state.c201
3 files changed, 205 insertions, 0 deletions
diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index eec7614..df3bd5a 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -49,3 +49,6 @@ config QCOM_SMD_RPM
Say M here if you want to include support for the Qualcomm RPM as a
module. This will build a module called "qcom-smd-rpm".
+
+config QCOM_SMEM_STATE
+ bool
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 10a93d1..d756033 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -3,3 +3,4 @@ obj-$(CONFIG_QCOM_PM) += spm.o
obj-$(CONFIG_QCOM_SMD) += smd.o
obj-$(CONFIG_QCOM_SMD_RPM) += smd-rpm.o
obj-$(CONFIG_QCOM_SMEM) += smem.o
+obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
diff --git a/drivers/soc/qcom/smem_state.c b/drivers/soc/qcom/smem_state.c
new file mode 100644
index 0000000..54261de
--- /dev/null
+++ b/drivers/soc/qcom/smem_state.c
@@ -0,0 +1,201 @@
+/*
+ * Copyright (c) 2015, Sony Mobile Communications Inc.
+ * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only 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.
+ */
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/soc/qcom/smem_state.h>
+
+static LIST_HEAD(smem_states);
+static DEFINE_MUTEX(list_lock);
+
+/**
+ * struct qcom_smem_state - state context
+ * @refcount: refcount for the state
+ * @orphan: boolean indicator that this state has been unregistered
+ * @list: entry in smem_states list
+ * @of_node: of_node to use for matching the state in DT
+ * @priv: implementation private data
+ * @ops: ops for the state
+ */
+struct qcom_smem_state {
+ struct kref refcount;
+ bool orphan;
+
+ struct list_head list;
+ struct device_node *of_node;
+
+ void *priv;
+
+ struct qcom_smem_state_ops ops;
+};
+
+/**
+ * qcom_smem_state_update_bits() - update the masked bits in state with value
+ * @state: state handle acquired by calling qcom_smem_state_get()
+ * @mask: bit mask for the change
+ * @value: new value for the masked bits
+ *
+ * Returns 0 on success, otherwise negative errno.
+ */
+int qcom_smem_state_update_bits(struct qcom_smem_state *state,
+ u32 mask,
+ u32 value)
+{
+ if (state->orphan)
+ return -ENXIO;
+
+ if (!state->ops.update_bits)
+ return -ENOTSUPP;
+
+ return state->ops.update_bits(state->priv, mask, value);
+}
+EXPORT_SYMBOL_GPL(qcom_smem_state_update_bits);
+
+static struct qcom_smem_state *of_node_to_state(struct device_node *np)
+{
+ struct qcom_smem_state *state;
+
+ mutex_lock(&list_lock);
+
+ list_for_each_entry(state, &smem_states, list) {
+ if (state->of_node == np) {
+ kref_get(&state->refcount);
+ goto unlock;
+ }
+ }
+ state = ERR_PTR(-EPROBE_DEFER);
+
+unlock:
+ mutex_unlock(&list_lock);
+
+ return state;
+}
+
+/**
+ * qcom_smem_state_get() - acquire handle to a state
+ * @dev: client device pointer
+ * @con_id: name of the state to lookup
+ * @bit: flags from the state reference, indicating which bit's affected
+ *
+ * Returns handle to the state, or ERR_PTR(). qcom_smem_state_put() must be
+ * called to release the returned state handle.
+ */
+struct qcom_smem_state *qcom_smem_state_get(struct device *dev,
+ const char *con_id,
+ unsigned *bit)
+{
+ struct qcom_smem_state *state;
+ struct of_phandle_args args;
+ int index = 0;
+ int ret;
+
+ if (con_id) {
+ index = of_property_match_string(dev->of_node,
+ "qcom,state-names",
+ con_id);
+ if (index < 0) {
+ dev_err(dev, "missing qcom,state-names\n");
+ return ERR_PTR(index);
+ }
+ }
+
+ ret = of_parse_phandle_with_args(dev->of_node,
+ "qcom,state",
+ "#qcom,state-cells",
+ index,
+ &args);
+ if (ret) {
+ dev_err(dev, "failed to parse qcom,state property\n");
+ return ERR_PTR(ret);
+ }
+
+ if (args.args_count != 1) {
+ dev_err(dev, "invalid #qcom,state-cells\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ state = of_node_to_state(args.np);
+ if (IS_ERR(state))
+ goto put;
+
+ *bit = args.args[0];
+
+put:
+ of_node_put(args.np);
+ return state;
+}
+EXPORT_SYMBOL_GPL(qcom_smem_state_get);
+
+static void qcom_smem_state_release(struct kref *ref)
+{
+ struct qcom_smem_state *state = container_of(ref, struct qcom_smem_state, refcount);
+
+ list_del(&state->list);
+ kfree(state);
+}
+
+/**
+ * qcom_smem_state_put() - release state handle
+ * @state: state handle to be released
+ */
+void qcom_smem_state_put(struct qcom_smem_state *state)
+{
+ mutex_lock(&list_lock);
+ kref_put(&state->refcount, qcom_smem_state_release);
+ mutex_unlock(&list_lock);
+}
+EXPORT_SYMBOL_GPL(qcom_smem_state_put);
+
+/**
+ * qcom_smem_state_register() - register a new state
+ * @of_node: of_node used for matching client lookups
+ * @ops: implementation ops
+ * @priv: implementation specific private data
+ */
+struct qcom_smem_state *qcom_smem_state_register(struct device_node *of_node,
+ const struct qcom_smem_state_ops *ops,
+ void *priv)
+{
+ struct qcom_smem_state *state;
+
+ state = kzalloc(sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return ERR_PTR(-ENOMEM);
+
+ kref_init(&state->refcount);
+
+ state->of_node = of_node;
+ state->ops = *ops;
+ state->priv = priv;
+
+ mutex_lock(&list_lock);
+ list_add(&state->list, &smem_states);
+ mutex_unlock(&list_lock);
+
+ return state;
+}
+EXPORT_SYMBOL_GPL(qcom_smem_state_register);
+
+/**
+ * qcom_smem_state_unregister() - unregister a registered state
+ * @state: state handle to be unregistered
+ */
+void qcom_smem_state_unregister(struct qcom_smem_state *state)
+{
+ state->orphan = true;
+ qcom_smem_state_put(state);
+}
+EXPORT_SYMBOL_GPL(qcom_smem_state_unregister);