summaryrefslogtreecommitdiff
path: root/drivers/slimbus/core.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/slimbus/core.c')
-rw-r--r--drivers/slimbus/core.c480
1 files changed, 480 insertions, 0 deletions
diff --git a/drivers/slimbus/core.c b/drivers/slimbus/core.c
new file mode 100644
index 000000000000..4988a8f4d905
--- /dev/null
+++ b/drivers/slimbus/core.c
@@ -0,0 +1,480 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2011-2017, The Linux Foundation
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/idr.h>
+#include <linux/of.h>
+#include <linux/pm_runtime.h>
+#include <linux/slimbus.h>
+#include "slimbus.h"
+
+static DEFINE_IDA(ctrl_ida);
+
+static const struct slim_device_id *slim_match(const struct slim_device_id *id,
+ const struct slim_device *sbdev)
+{
+ while (id->manf_id != 0 || id->prod_code != 0) {
+ if (id->manf_id == sbdev->e_addr.manf_id &&
+ id->prod_code == sbdev->e_addr.prod_code)
+ return id;
+ id++;
+ }
+ return NULL;
+}
+
+static int slim_device_match(struct device *dev, struct device_driver *drv)
+{
+ struct slim_device *sbdev = to_slim_device(dev);
+ struct slim_driver *sbdrv = to_slim_driver(drv);
+
+ return !!slim_match(sbdrv->id_table, sbdev);
+}
+
+static int slim_device_probe(struct device *dev)
+{
+ struct slim_device *sbdev = to_slim_device(dev);
+ struct slim_driver *sbdrv = to_slim_driver(dev->driver);
+
+ return sbdrv->probe(sbdev);
+}
+
+static int slim_device_remove(struct device *dev)
+{
+ struct slim_device *sbdev = to_slim_device(dev);
+ struct slim_driver *sbdrv;
+
+ if (dev->driver) {
+ sbdrv = to_slim_driver(dev->driver);
+ if (sbdrv->remove)
+ sbdrv->remove(sbdev);
+ }
+
+ return 0;
+}
+
+struct bus_type slimbus_bus = {
+ .name = "slimbus",
+ .match = slim_device_match,
+ .probe = slim_device_probe,
+ .remove = slim_device_remove,
+};
+EXPORT_SYMBOL_GPL(slimbus_bus);
+
+/*
+ * __slim_driver_register() - Client driver registration with SLIMbus
+ *
+ * @drv:Client driver to be associated with client-device.
+ * @owner: owning module/driver
+ *
+ * This API will register the client driver with the SLIMbus
+ * It is called from the driver's module-init function.
+ */
+int __slim_driver_register(struct slim_driver *drv, struct module *owner)
+{
+ /* ID table and probe are mandatory */
+ if (!drv->id_table || !drv->probe)
+ return -EINVAL;
+
+ drv->driver.bus = &slimbus_bus;
+ drv->driver.owner = owner;
+
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(__slim_driver_register);
+
+/*
+ * slim_driver_unregister() - Undo effect of slim_driver_register
+ *
+ * @drv: Client driver to be unregistered
+ */
+void slim_driver_unregister(struct slim_driver *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(slim_driver_unregister);
+
+static void slim_dev_release(struct device *dev)
+{
+ struct slim_device *sbdev = to_slim_device(dev);
+
+ kfree(sbdev);
+}
+
+static int slim_add_device(struct slim_controller *ctrl,
+ struct slim_device *sbdev,
+ struct device_node *node)
+{
+ sbdev->dev.bus = &slimbus_bus;
+ sbdev->dev.parent = ctrl->dev;
+ sbdev->dev.release = slim_dev_release;
+ sbdev->dev.driver = NULL;
+ sbdev->ctrl = ctrl;
+
+ if (node)
+ sbdev->dev.of_node = of_node_get(node);
+
+ dev_set_name(&sbdev->dev, "%x:%x:%x:%x",
+ sbdev->e_addr.manf_id,
+ sbdev->e_addr.prod_code,
+ sbdev->e_addr.dev_index,
+ sbdev->e_addr.instance);
+
+ return device_register(&sbdev->dev);
+}
+
+static struct slim_device *slim_alloc_device(struct slim_controller *ctrl,
+ struct slim_eaddr *eaddr,
+ struct device_node *node)
+{
+ struct slim_device *sbdev;
+ int ret;
+
+ sbdev = kzalloc(sizeof(*sbdev), GFP_KERNEL);
+ if (!sbdev)
+ return NULL;
+
+ sbdev->e_addr = *eaddr;
+ ret = slim_add_device(ctrl, sbdev, node);
+ if (ret) {
+ kfree(sbdev);
+ return NULL;
+ }
+
+ return sbdev;
+}
+
+static void of_register_slim_devices(struct slim_controller *ctrl)
+{
+ struct device *dev = ctrl->dev;
+ struct device_node *node;
+
+ if (!ctrl->dev->of_node)
+ return;
+
+ for_each_child_of_node(ctrl->dev->of_node, node) {
+ struct slim_device *sbdev;
+ struct slim_eaddr e_addr;
+ const char *compat = NULL;
+ int reg[2], ret;
+ int manf_id, prod_code;
+
+ compat = of_get_property(node, "compatible", NULL);
+ if (!compat)
+ continue;
+
+ ret = sscanf(compat, "slim%x,%x", &manf_id, &prod_code);
+ if (ret != 2) {
+ dev_err(dev, "Manf ID & Product code not found %s\n",
+ compat);
+ continue;
+ }
+
+ ret = of_property_read_u32_array(node, "reg", reg, 2);
+ if (ret) {
+ dev_err(dev, "Device and Instance id not found:%d\n",
+ ret);
+ continue;
+ }
+
+ e_addr.dev_index = reg[0];
+ e_addr.instance = reg[1];
+ e_addr.manf_id = manf_id;
+ e_addr.prod_code = prod_code;
+
+ sbdev = slim_alloc_device(ctrl, &e_addr, node);
+ if (!sbdev)
+ continue;
+ }
+}
+
+/*
+ * slim_register_controller() - Controller bring-up and registration.
+ *
+ * @ctrl: Controller to be registered.
+ *
+ * A controller is registered with the framework using this API.
+ * If devices on a controller were registered before controller,
+ * this will make sure that they get probed when controller is up
+ */
+int slim_register_controller(struct slim_controller *ctrl)
+{
+ int id;
+
+ id = ida_simple_get(&ctrl_ida, 0, 0, GFP_KERNEL);
+ if (id < 0)
+ return id;
+
+ ctrl->id = id;
+
+ if (!ctrl->min_cg)
+ ctrl->min_cg = SLIM_MIN_CLK_GEAR;
+ if (!ctrl->max_cg)
+ ctrl->max_cg = SLIM_MAX_CLK_GEAR;
+
+ ida_init(&ctrl->laddr_ida);
+ idr_init(&ctrl->tid_idr);
+ mutex_init(&ctrl->lock);
+ mutex_init(&ctrl->sched.m_reconf);
+ init_completion(&ctrl->sched.pause_comp);
+
+ dev_dbg(ctrl->dev, "Bus [%s] registered:dev:%p\n",
+ ctrl->name, ctrl->dev);
+
+ of_register_slim_devices(ctrl);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(slim_register_controller);
+
+/* slim_remove_device: Remove the effect of slim_add_device() */
+static void slim_remove_device(struct slim_device *sbdev)
+{
+ device_unregister(&sbdev->dev);
+}
+
+static int slim_ctrl_remove_device(struct device *dev, void *null)
+{
+ slim_remove_device(to_slim_device(dev));
+ return 0;
+}
+
+/**
+ * slim_unregister_controller() - Controller tear-down.
+ *
+ * @ctrl: Controller to tear-down.
+ */
+int slim_unregister_controller(struct slim_controller *ctrl)
+{
+ /* Remove all clients */
+ device_for_each_child(ctrl->dev, NULL, slim_ctrl_remove_device);
+ /* Enter Clock Pause */
+ slim_ctrl_clk_pause(ctrl, false, 0);
+ ida_simple_remove(&ctrl_ida, ctrl->id);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(slim_unregister_controller);
+
+static void slim_device_update_status(struct slim_device *sbdev,
+ enum slim_device_status status)
+{
+ struct slim_driver *sbdrv;
+
+ if (sbdev->status == status)
+ return;
+
+ sbdev->status = status;
+ if (!sbdev->dev.driver)
+ return;
+
+ sbdrv = to_slim_driver(sbdev->dev.driver);
+ if (sbdrv->device_status)
+ sbdrv->device_status(sbdev, sbdev->status);
+}
+
+/**
+ * slim_report_absent() - Controller calls this function when a device
+ * reports absent, OR when the device cannot be communicated with
+ *
+ * @sbdev: Device that cannot be reached, or sent report absent
+ */
+void slim_report_absent(struct slim_device *sbdev)
+{
+ struct slim_controller *ctrl = sbdev->ctrl;
+
+ if (!ctrl)
+ return;
+
+ /* invalidate logical addresses */
+ mutex_lock(&ctrl->lock);
+ sbdev->is_laddr_valid = false;
+ mutex_unlock(&ctrl->lock);
+
+ ida_simple_remove(&ctrl->laddr_ida, sbdev->laddr);
+ slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_DOWN);
+}
+EXPORT_SYMBOL_GPL(slim_report_absent);
+
+static bool slim_eaddr_equal(struct slim_eaddr *a, struct slim_eaddr *b)
+{
+ return (a->manf_id == b->manf_id &&
+ a->prod_code == b->prod_code &&
+ a->dev_index == b->dev_index &&
+ a->instance == b->instance);
+}
+
+static int slim_match_dev(struct device *dev, void *data)
+{
+ struct slim_eaddr *e_addr = data;
+ struct slim_device *sbdev = to_slim_device(dev);
+
+ return slim_eaddr_equal(&sbdev->e_addr, e_addr);
+}
+
+static struct slim_device *find_slim_device(struct slim_controller *ctrl,
+ struct slim_eaddr *eaddr)
+{
+ struct slim_device *sbdev;
+ struct device *dev;
+
+ dev = device_find_child(ctrl->dev, eaddr, slim_match_dev);
+ if (dev) {
+ sbdev = to_slim_device(dev);
+ return sbdev;
+ }
+
+ return NULL;
+}
+
+/**
+ * slim_get_device() - get handle to a device.
+ *
+ * @ctrl: Controller on which this device will be added/queried
+ * @e_addr: Enumeration address of the device to be queried
+ *
+ * Return: pointer to a device if it has already reported. Creates a new
+ * device and returns pointer to it if the device has not yet enumerated.
+ */
+struct slim_device *slim_get_device(struct slim_controller *ctrl,
+ struct slim_eaddr *e_addr)
+{
+ struct slim_device *sbdev;
+
+ sbdev = find_slim_device(ctrl, e_addr);
+ if (!sbdev) {
+ sbdev = slim_alloc_device(ctrl, e_addr, NULL);
+ if (!sbdev)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return sbdev;
+}
+EXPORT_SYMBOL_GPL(slim_get_device);
+
+static int slim_device_alloc_laddr(struct slim_device *sbdev,
+ bool report_present)
+{
+ struct slim_controller *ctrl = sbdev->ctrl;
+ u8 laddr;
+ int ret;
+
+ mutex_lock(&ctrl->lock);
+ if (ctrl->get_laddr) {
+ ret = ctrl->get_laddr(ctrl, &sbdev->e_addr, &laddr);
+ if (ret < 0)
+ goto err;
+ } else if (report_present) {
+ ret = ida_simple_get(&ctrl->laddr_ida,
+ 0, SLIM_LA_MANAGER - 1, GFP_KERNEL);
+ if (ret < 0)
+ goto err;
+
+ laddr = ret;
+ } else {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ if (ctrl->set_laddr) {
+ ret = ctrl->set_laddr(ctrl, &sbdev->e_addr, laddr);
+ if (ret) {
+ ret = -EINVAL;
+ goto err;
+ }
+ }
+
+ sbdev->laddr = laddr;
+ sbdev->is_laddr_valid = true;
+
+ slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_UP);
+
+ dev_dbg(ctrl->dev, "setting slimbus l-addr:%x, ea:%x,%x,%x,%x\n",
+ laddr, sbdev->e_addr.manf_id, sbdev->e_addr.prod_code,
+ sbdev->e_addr.dev_index, sbdev->e_addr.instance);
+
+err:
+ mutex_unlock(&ctrl->lock);
+ return ret;
+
+}
+
+/**
+ * slim_device_report_present() - Report enumerated device.
+ *
+ * @ctrl: Controller with which device is enumerated.
+ * @e_addr: Enumeration address of the device.
+ * @laddr: Return logical address (if valid flag is false)
+ *
+ * Called by controller in response to REPORT_PRESENT. Framework will assign
+ * a logical address to this enumeration address.
+ * Function returns -EXFULL to indicate that all logical addresses are already
+ * taken.
+ */
+int slim_device_report_present(struct slim_controller *ctrl,
+ struct slim_eaddr *e_addr, u8 *laddr)
+{
+ struct slim_device *sbdev;
+ int ret;
+
+ ret = pm_runtime_get_sync(ctrl->dev);
+
+ if (ctrl->sched.clk_state != SLIM_CLK_ACTIVE) {
+ dev_err(ctrl->dev, "slim ctrl not active,state:%d, ret:%d\n",
+ ctrl->sched.clk_state, ret);
+ goto slimbus_not_active;
+ }
+
+ sbdev = slim_get_device(ctrl, e_addr);
+ if (IS_ERR(sbdev))
+ return -ENODEV;
+
+ if (sbdev->is_laddr_valid) {
+ *laddr = sbdev->laddr;
+ return 0;
+ }
+
+ ret = slim_device_alloc_laddr(sbdev, true);
+
+slimbus_not_active:
+ pm_runtime_mark_last_busy(ctrl->dev);
+ pm_runtime_put_autosuspend(ctrl->dev);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(slim_device_report_present);
+
+/**
+ * slim_get_logical_addr() - get/allocate logical address of a SLIMbus device.
+ *
+ * @sbdev: client handle requesting the address.
+ *
+ * Return: zero if a logical address is valid or a new logical address
+ * has been assigned. error code in case of error.
+ */
+int slim_get_logical_addr(struct slim_device *sbdev)
+{
+ if (!sbdev->is_laddr_valid)
+ return slim_device_alloc_laddr(sbdev, false);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(slim_get_logical_addr);
+
+static void __exit slimbus_exit(void)
+{
+ bus_unregister(&slimbus_bus);
+}
+module_exit(slimbus_exit);
+
+static int __init slimbus_init(void)
+{
+ return bus_register(&slimbus_bus);
+}
+postcore_initcall(slimbus_init);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("SLIMbus core");