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-rw-r--r--arch/arm/mach-omap2/omap_device.c887
1 files changed, 887 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c
new file mode 100644
index 000000000..23e8146b9
--- /dev/null
+++ b/arch/arm/mach-omap2/omap_device.c
@@ -0,0 +1,887 @@
+/*
+ * omap_device implementation
+ *
+ * Copyright (C) 2009-2010 Nokia Corporation
+ * Paul Walmsley, Kevin Hilman
+ *
+ * Developed in collaboration with (alphabetical order): Benoit
+ * Cousson, Thara Gopinath, Tony Lindgren, Rajendra Nayak, Vikram
+ * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
+ * Woodruff
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This code provides a consistent interface for OMAP device drivers
+ * to control power management and interconnect properties of their
+ * devices.
+ *
+ * In the medium- to long-term, this code should be implemented as a
+ * proper omap_bus/omap_device in Linux, no more platform_data func
+ * pointers
+ *
+ *
+ */
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/notifier.h>
+
+#include "common.h"
+#include "soc.h"
+#include "omap_device.h"
+#include "omap_hwmod.h"
+
+/* Private functions */
+
+static void _add_clkdev(struct omap_device *od, const char *clk_alias,
+ const char *clk_name)
+{
+ struct clk *r;
+ int rc;
+
+ if (!clk_alias || !clk_name)
+ return;
+
+ dev_dbg(&od->pdev->dev, "Creating %s -> %s\n", clk_alias, clk_name);
+
+ r = clk_get_sys(dev_name(&od->pdev->dev), clk_alias);
+ if (!IS_ERR(r)) {
+ dev_dbg(&od->pdev->dev,
+ "alias %s already exists\n", clk_alias);
+ clk_put(r);
+ return;
+ }
+
+ r = clk_get_sys(NULL, clk_name);
+
+ if (IS_ERR(r)) {
+ struct of_phandle_args clkspec;
+
+ clkspec.np = of_find_node_by_name(NULL, clk_name);
+
+ r = of_clk_get_from_provider(&clkspec);
+
+ rc = clk_register_clkdev(r, clk_alias,
+ dev_name(&od->pdev->dev));
+ } else {
+ rc = clk_add_alias(clk_alias, dev_name(&od->pdev->dev),
+ clk_name, NULL);
+ }
+
+ if (rc) {
+ if (rc == -ENODEV || rc == -ENOMEM)
+ dev_err(&od->pdev->dev,
+ "clkdev_alloc for %s failed\n", clk_alias);
+ else
+ dev_err(&od->pdev->dev,
+ "clk_get for %s failed\n", clk_name);
+ }
+}
+
+/**
+ * _add_hwmod_clocks_clkdev - Add clkdev entry for hwmod optional clocks
+ * and main clock
+ * @od: struct omap_device *od
+ * @oh: struct omap_hwmod *oh
+ *
+ * For the main clock and every optional clock present per hwmod per
+ * omap_device, this function adds an entry in the clkdev table of the
+ * form <dev-id=dev_name, con-id=role> if it does not exist already.
+ *
+ * The function is called from inside omap_device_build_ss(), after
+ * omap_device_register.
+ *
+ * This allows drivers to get a pointer to its optional clocks based on its role
+ * by calling clk_get(<dev*>, <role>).
+ * In the case of the main clock, a "fck" alias is used.
+ *
+ * No return value.
+ */
+static void _add_hwmod_clocks_clkdev(struct omap_device *od,
+ struct omap_hwmod *oh)
+{
+ int i;
+
+ _add_clkdev(od, "fck", oh->main_clk);
+
+ for (i = 0; i < oh->opt_clks_cnt; i++)
+ _add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
+}
+
+
+/**
+ * omap_device_build_from_dt - build an omap_device with multiple hwmods
+ * @pdev_name: name of the platform_device driver to use
+ * @pdev_id: this platform_device's connection ID
+ * @oh: ptr to the single omap_hwmod that backs this omap_device
+ * @pdata: platform_data ptr to associate with the platform_device
+ * @pdata_len: amount of memory pointed to by @pdata
+ *
+ * Function for building an omap_device already registered from device-tree
+ *
+ * Returns 0 or PTR_ERR() on error.
+ */
+static int omap_device_build_from_dt(struct platform_device *pdev)
+{
+ struct omap_hwmod **hwmods;
+ struct omap_device *od;
+ struct omap_hwmod *oh;
+ struct device_node *node = pdev->dev.of_node;
+ struct resource res;
+ const char *oh_name;
+ int oh_cnt, i, ret = 0;
+ bool device_active = false, skip_pm_domain = false;
+
+ oh_cnt = of_property_count_strings(node, "ti,hwmods");
+ if (oh_cnt <= 0) {
+ dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
+ return -ENODEV;
+ }
+
+ /* SDMA still needs special handling for omap_device_build() */
+ ret = of_property_read_string_index(node, "ti,hwmods", 0, &oh_name);
+ if (!ret && (!strncmp("dma_system", oh_name, 10) ||
+ !strncmp("dma", oh_name, 3)))
+ skip_pm_domain = true;
+
+ /* Use ti-sysc driver instead of omap_device? */
+ if (!skip_pm_domain &&
+ !omap_hwmod_parse_module_range(NULL, node, &res))
+ return -ENODEV;
+
+ hwmods = kcalloc(oh_cnt, sizeof(struct omap_hwmod *), GFP_KERNEL);
+ if (!hwmods) {
+ ret = -ENOMEM;
+ goto odbfd_exit;
+ }
+
+ for (i = 0; i < oh_cnt; i++) {
+ of_property_read_string_index(node, "ti,hwmods", i, &oh_name);
+ oh = omap_hwmod_lookup(oh_name);
+ if (!oh) {
+ dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
+ oh_name);
+ ret = -EINVAL;
+ goto odbfd_exit1;
+ }
+ hwmods[i] = oh;
+ if (oh->flags & HWMOD_INIT_NO_IDLE)
+ device_active = true;
+ }
+
+ od = omap_device_alloc(pdev, hwmods, oh_cnt);
+ if (IS_ERR(od)) {
+ dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
+ oh_name);
+ ret = PTR_ERR(od);
+ goto odbfd_exit1;
+ }
+
+ /* Fix up missing resource names */
+ for (i = 0; i < pdev->num_resources; i++) {
+ struct resource *r = &pdev->resource[i];
+
+ if (r->name == NULL)
+ r->name = dev_name(&pdev->dev);
+ }
+
+ if (!skip_pm_domain) {
+ dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
+ if (device_active) {
+ omap_device_enable(pdev);
+ pm_runtime_set_active(&pdev->dev);
+ }
+ }
+
+odbfd_exit1:
+ kfree(hwmods);
+odbfd_exit:
+ /* if data/we are at fault.. load up a fail handler */
+ if (ret)
+ dev_pm_domain_set(&pdev->dev, &omap_device_fail_pm_domain);
+
+ return ret;
+}
+
+static int _omap_device_notifier_call(struct notifier_block *nb,
+ unsigned long event, void *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct omap_device *od;
+ int err;
+
+ switch (event) {
+ case BUS_NOTIFY_REMOVED_DEVICE:
+ if (pdev->archdata.od)
+ omap_device_delete(pdev->archdata.od);
+ break;
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ od = to_omap_device(pdev);
+ if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) {
+ dev_info(dev, "enabled after unload, idling\n");
+ err = omap_device_idle(pdev);
+ if (err)
+ dev_err(dev, "failed to idle\n");
+ }
+ break;
+ case BUS_NOTIFY_BIND_DRIVER:
+ od = to_omap_device(pdev);
+ if (od) {
+ od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
+ if (od->_state == OMAP_DEVICE_STATE_ENABLED &&
+ pm_runtime_status_suspended(dev)) {
+ pm_runtime_set_active(dev);
+ }
+ }
+ break;
+ case BUS_NOTIFY_ADD_DEVICE:
+ if (pdev->dev.of_node)
+ omap_device_build_from_dt(pdev);
+ omap_auxdata_legacy_init(dev);
+ /* fall through */
+ default:
+ od = to_omap_device(pdev);
+ if (od)
+ od->_driver_status = event;
+ }
+
+ return NOTIFY_DONE;
+}
+
+/**
+ * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
+ * @od: struct omap_device *od
+ *
+ * Enable all underlying hwmods. Returns 0.
+ */
+static int _omap_device_enable_hwmods(struct omap_device *od)
+{
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < od->hwmods_cnt; i++)
+ ret |= omap_hwmod_enable(od->hwmods[i]);
+
+ return ret;
+}
+
+/**
+ * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
+ * @od: struct omap_device *od
+ *
+ * Idle all underlying hwmods. Returns 0.
+ */
+static int _omap_device_idle_hwmods(struct omap_device *od)
+{
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < od->hwmods_cnt; i++)
+ ret |= omap_hwmod_idle(od->hwmods[i]);
+
+ return ret;
+}
+
+/* Public functions for use by core code */
+
+/**
+ * omap_device_get_context_loss_count - get lost context count
+ * @od: struct omap_device *
+ *
+ * Using the primary hwmod, query the context loss count for this
+ * device.
+ *
+ * Callers should consider context for this device lost any time this
+ * function returns a value different than the value the caller got
+ * the last time it called this function.
+ *
+ * If any hwmods exist for the omap_device associated with @pdev,
+ * return the context loss counter for that hwmod, otherwise return
+ * zero.
+ */
+int omap_device_get_context_loss_count(struct platform_device *pdev)
+{
+ struct omap_device *od;
+ u32 ret = 0;
+
+ od = to_omap_device(pdev);
+
+ if (od->hwmods_cnt)
+ ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
+
+ return ret;
+}
+
+/**
+ * omap_device_alloc - allocate an omap_device
+ * @pdev: platform_device that will be included in this omap_device
+ * @oh: ptr to the single omap_hwmod that backs this omap_device
+ * @pdata: platform_data ptr to associate with the platform_device
+ * @pdata_len: amount of memory pointed to by @pdata
+ *
+ * Convenience function for allocating an omap_device structure and filling
+ * hwmods, and resources.
+ *
+ * Returns an struct omap_device pointer or ERR_PTR() on error;
+ */
+struct omap_device *omap_device_alloc(struct platform_device *pdev,
+ struct omap_hwmod **ohs, int oh_cnt)
+{
+ int ret = -ENOMEM;
+ struct omap_device *od;
+ int i;
+ struct omap_hwmod **hwmods;
+
+ od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
+ if (!od) {
+ ret = -ENOMEM;
+ goto oda_exit1;
+ }
+ od->hwmods_cnt = oh_cnt;
+
+ hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
+ if (!hwmods)
+ goto oda_exit2;
+
+ od->hwmods = hwmods;
+ od->pdev = pdev;
+ pdev->archdata.od = od;
+
+ for (i = 0; i < oh_cnt; i++) {
+ hwmods[i]->od = od;
+ _add_hwmod_clocks_clkdev(od, hwmods[i]);
+ }
+
+ return od;
+
+oda_exit2:
+ kfree(od);
+oda_exit1:
+ dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
+
+ return ERR_PTR(ret);
+}
+
+void omap_device_delete(struct omap_device *od)
+{
+ if (!od)
+ return;
+
+ od->pdev->archdata.od = NULL;
+ kfree(od->hwmods);
+ kfree(od);
+}
+
+/**
+ * omap_device_copy_resources - Add legacy IO and IRQ resources
+ * @oh: interconnect target module
+ * @pdev: platform device to copy resources to
+ *
+ * We still have legacy DMA and smartreflex needing resources.
+ * Let's populate what they need until we can eventually just
+ * remove this function. Note that there should be no need to
+ * call this from omap_device_build_from_dt(), nor should there
+ * be any need to call it for other devices.
+ */
+static int
+omap_device_copy_resources(struct omap_hwmod *oh,
+ struct platform_device *pdev)
+{
+ struct device_node *np, *child;
+ struct property *prop;
+ struct resource *res;
+ const char *name;
+ int error, irq = 0;
+
+ if (!oh || !oh->od || !oh->od->pdev)
+ return -EINVAL;
+
+ np = oh->od->pdev->dev.of_node;
+ if (!np) {
+ error = -ENODEV;
+ goto error;
+ }
+
+ res = kcalloc(2, sizeof(*res), GFP_KERNEL);
+ if (!res)
+ return -ENOMEM;
+
+ /* Do we have a dts range for the interconnect target module? */
+ error = omap_hwmod_parse_module_range(oh, np, res);
+
+ /* No ranges, rely on device reg entry */
+ if (error)
+ error = of_address_to_resource(np, 0, res);
+ if (error)
+ goto free;
+
+ /* SmartReflex needs first IO resource name to be "mpu" */
+ res[0].name = "mpu";
+
+ /*
+ * We may have a configured "ti,sysc" interconnect target with a
+ * dts child with the interrupt. If so use the first child's
+ * first interrupt for "ti-hwmods" legacy support.
+ */
+ of_property_for_each_string(np, "compatible", prop, name)
+ if (!strncmp("ti,sysc-", name, 8))
+ break;
+
+ child = of_get_next_available_child(np, NULL);
+
+ if (name)
+ irq = irq_of_parse_and_map(child, 0);
+ if (!irq)
+ irq = irq_of_parse_and_map(np, 0);
+ if (!irq) {
+ error = -EINVAL;
+ goto free;
+ }
+
+ /* Legacy DMA code needs interrupt name to be "0" */
+ res[1].start = irq;
+ res[1].end = irq;
+ res[1].flags = IORESOURCE_IRQ;
+ res[1].name = "0";
+
+ error = platform_device_add_resources(pdev, res, 2);
+
+free:
+ kfree(res);
+
+error:
+ WARN(error, "%s: %s device %s failed: %i\n",
+ __func__, oh->name, dev_name(&pdev->dev),
+ error);
+
+ return error;
+}
+
+/**
+ * omap_device_build - build and register an omap_device with one omap_hwmod
+ * @pdev_name: name of the platform_device driver to use
+ * @pdev_id: this platform_device's connection ID
+ * @oh: ptr to the single omap_hwmod that backs this omap_device
+ * @pdata: platform_data ptr to associate with the platform_device
+ * @pdata_len: amount of memory pointed to by @pdata
+ *
+ * Convenience function for building and registering a single
+ * omap_device record, which in turn builds and registers a
+ * platform_device record. See omap_device_build_ss() for more
+ * information. Returns ERR_PTR(-EINVAL) if @oh is NULL; otherwise,
+ * passes along the return value of omap_device_build_ss().
+ */
+struct platform_device __init *omap_device_build(const char *pdev_name,
+ int pdev_id,
+ struct omap_hwmod *oh,
+ void *pdata, int pdata_len)
+{
+ int ret = -ENOMEM;
+ struct platform_device *pdev;
+ struct omap_device *od;
+
+ if (!oh || !pdev_name)
+ return ERR_PTR(-EINVAL);
+
+ if (!pdata && pdata_len > 0)
+ return ERR_PTR(-EINVAL);
+
+ if (strncmp(oh->name, "smartreflex", 11) &&
+ strncmp(oh->name, "dma", 3)) {
+ pr_warn("%s need to update %s to probe with dt\na",
+ __func__, pdev_name);
+ ret = -ENODEV;
+ goto odbs_exit;
+ }
+
+ pdev = platform_device_alloc(pdev_name, pdev_id);
+ if (!pdev) {
+ ret = -ENOMEM;
+ goto odbs_exit;
+ }
+
+ /* Set the dev_name early to allow dev_xxx in omap_device_alloc */
+ if (pdev->id != -1)
+ dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
+ else
+ dev_set_name(&pdev->dev, "%s", pdev->name);
+
+ /*
+ * Must be called before omap_device_alloc() as oh->od
+ * only contains the currently registered omap_device
+ * and will get overwritten by omap_device_alloc().
+ */
+ ret = omap_device_copy_resources(oh, pdev);
+ if (ret)
+ goto odbs_exit1;
+
+ od = omap_device_alloc(pdev, &oh, 1);
+ if (IS_ERR(od)) {
+ ret = PTR_ERR(od);
+ goto odbs_exit1;
+ }
+
+ ret = platform_device_add_data(pdev, pdata, pdata_len);
+ if (ret)
+ goto odbs_exit2;
+
+ ret = omap_device_register(pdev);
+ if (ret)
+ goto odbs_exit2;
+
+ return pdev;
+
+odbs_exit2:
+ omap_device_delete(od);
+odbs_exit1:
+ platform_device_put(pdev);
+odbs_exit:
+
+ pr_err("omap_device: %s: build failed (%d)\n", pdev_name, ret);
+
+ return ERR_PTR(ret);
+}
+
+#ifdef CONFIG_PM
+static int _od_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ int ret;
+
+ ret = pm_generic_runtime_suspend(dev);
+ if (ret)
+ return ret;
+
+ return omap_device_idle(pdev);
+}
+
+static int _od_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ int ret;
+
+ ret = omap_device_enable(pdev);
+ if (ret) {
+ dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
+ return ret;
+ }
+
+ return pm_generic_runtime_resume(dev);
+}
+
+static int _od_fail_runtime_suspend(struct device *dev)
+{
+ dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
+ return -ENODEV;
+}
+
+static int _od_fail_runtime_resume(struct device *dev)
+{
+ dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
+ return -ENODEV;
+}
+
+#endif
+
+#ifdef CONFIG_SUSPEND
+static int _od_suspend_noirq(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct omap_device *od = to_omap_device(pdev);
+ int ret;
+
+ /* Don't attempt late suspend on a driver that is not bound */
+ if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
+ return 0;
+
+ ret = pm_generic_suspend_noirq(dev);
+
+ if (!ret && !pm_runtime_status_suspended(dev)) {
+ if (pm_generic_runtime_suspend(dev) == 0) {
+ omap_device_idle(pdev);
+ od->flags |= OMAP_DEVICE_SUSPENDED;
+ }
+ }
+
+ return ret;
+}
+
+static int _od_resume_noirq(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct omap_device *od = to_omap_device(pdev);
+
+ if (od->flags & OMAP_DEVICE_SUSPENDED) {
+ od->flags &= ~OMAP_DEVICE_SUSPENDED;
+ omap_device_enable(pdev);
+ pm_generic_runtime_resume(dev);
+ }
+
+ return pm_generic_resume_noirq(dev);
+}
+#else
+#define _od_suspend_noirq NULL
+#define _od_resume_noirq NULL
+#endif
+
+struct dev_pm_domain omap_device_fail_pm_domain = {
+ .ops = {
+ SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
+ _od_fail_runtime_resume, NULL)
+ }
+};
+
+struct dev_pm_domain omap_device_pm_domain = {
+ .ops = {
+ SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
+ NULL)
+ USE_PLATFORM_PM_SLEEP_OPS
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
+ _od_resume_noirq)
+ }
+};
+
+/**
+ * omap_device_register - register an omap_device with one omap_hwmod
+ * @od: struct omap_device * to register
+ *
+ * Register the omap_device structure. This currently just calls
+ * platform_device_register() on the underlying platform_device.
+ * Returns the return value of platform_device_register().
+ */
+int omap_device_register(struct platform_device *pdev)
+{
+ pr_debug("omap_device: %s: registering\n", pdev->name);
+
+ dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
+ return platform_device_add(pdev);
+}
+
+
+/* Public functions for use by device drivers through struct platform_data */
+
+/**
+ * omap_device_enable - fully activate an omap_device
+ * @od: struct omap_device * to activate
+ *
+ * Do whatever is necessary for the hwmods underlying omap_device @od
+ * to be accessible and ready to operate. This generally involves
+ * enabling clocks, setting SYSCONFIG registers; and in the future may
+ * involve remuxing pins. Device drivers should call this function
+ * indirectly via pm_runtime_get*(). Returns -EINVAL if called when
+ * the omap_device is already enabled, or passes along the return
+ * value of _omap_device_enable_hwmods().
+ */
+int omap_device_enable(struct platform_device *pdev)
+{
+ int ret;
+ struct omap_device *od;
+
+ od = to_omap_device(pdev);
+
+ if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
+ dev_warn(&pdev->dev,
+ "omap_device: %s() called from invalid state %d\n",
+ __func__, od->_state);
+ return -EINVAL;
+ }
+
+ ret = _omap_device_enable_hwmods(od);
+
+ if (ret == 0)
+ od->_state = OMAP_DEVICE_STATE_ENABLED;
+
+ return ret;
+}
+
+/**
+ * omap_device_idle - idle an omap_device
+ * @od: struct omap_device * to idle
+ *
+ * Idle omap_device @od. Device drivers call this function indirectly
+ * via pm_runtime_put*(). Returns -EINVAL if the omap_device is not
+ * currently enabled, or passes along the return value of
+ * _omap_device_idle_hwmods().
+ */
+int omap_device_idle(struct platform_device *pdev)
+{
+ int ret;
+ struct omap_device *od;
+
+ od = to_omap_device(pdev);
+
+ if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
+ dev_warn(&pdev->dev,
+ "omap_device: %s() called from invalid state %d\n",
+ __func__, od->_state);
+ return -EINVAL;
+ }
+
+ ret = _omap_device_idle_hwmods(od);
+
+ if (ret == 0)
+ od->_state = OMAP_DEVICE_STATE_IDLE;
+
+ return ret;
+}
+
+/**
+ * omap_device_assert_hardreset - set a device's hardreset line
+ * @pdev: struct platform_device * to reset
+ * @name: const char * name of the reset line
+ *
+ * Set the hardreset line identified by @name on the IP blocks
+ * associated with the hwmods backing the platform_device @pdev. All
+ * of the hwmods associated with @pdev must have the same hardreset
+ * line linked to them for this to work. Passes along the return value
+ * of omap_hwmod_assert_hardreset() in the event of any failure, or
+ * returns 0 upon success.
+ */
+int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
+{
+ struct omap_device *od = to_omap_device(pdev);
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < od->hwmods_cnt; i++) {
+ ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * omap_device_deassert_hardreset - release a device's hardreset line
+ * @pdev: struct platform_device * to reset
+ * @name: const char * name of the reset line
+ *
+ * Release the hardreset line identified by @name on the IP blocks
+ * associated with the hwmods backing the platform_device @pdev. All
+ * of the hwmods associated with @pdev must have the same hardreset
+ * line linked to them for this to work. Passes along the return
+ * value of omap_hwmod_deassert_hardreset() in the event of any
+ * failure, or returns 0 upon success.
+ */
+int omap_device_deassert_hardreset(struct platform_device *pdev,
+ const char *name)
+{
+ struct omap_device *od = to_omap_device(pdev);
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < od->hwmods_cnt; i++) {
+ ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * omap_device_get_by_hwmod_name() - convert a hwmod name to
+ * device pointer.
+ * @oh_name: name of the hwmod device
+ *
+ * Returns back a struct device * pointer associated with a hwmod
+ * device represented by a hwmod_name
+ */
+struct device *omap_device_get_by_hwmod_name(const char *oh_name)
+{
+ struct omap_hwmod *oh;
+
+ if (!oh_name) {
+ WARN(1, "%s: no hwmod name!\n", __func__);
+ return ERR_PTR(-EINVAL);
+ }
+
+ oh = omap_hwmod_lookup(oh_name);
+ if (!oh) {
+ WARN(1, "%s: no hwmod for %s\n", __func__,
+ oh_name);
+ return ERR_PTR(-ENODEV);
+ }
+ if (!oh->od) {
+ WARN(1, "%s: no omap_device for %s\n", __func__,
+ oh_name);
+ return ERR_PTR(-ENODEV);
+ }
+
+ return &oh->od->pdev->dev;
+}
+
+static struct notifier_block platform_nb = {
+ .notifier_call = _omap_device_notifier_call,
+};
+
+static int __init omap_device_init(void)
+{
+ bus_register_notifier(&platform_bus_type, &platform_nb);
+ return 0;
+}
+omap_postcore_initcall(omap_device_init);
+
+/**
+ * omap_device_late_idle - idle devices without drivers
+ * @dev: struct device * associated with omap_device
+ * @data: unused
+ *
+ * Check the driver bound status of this device, and idle it
+ * if there is no driver attached.
+ */
+static int __init omap_device_late_idle(struct device *dev, void *data)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct omap_device *od = to_omap_device(pdev);
+ int i;
+
+ if (!od)
+ return 0;
+
+ /*
+ * If omap_device state is enabled, but has no driver bound,
+ * idle it.
+ */
+
+ /*
+ * Some devices (like memory controllers) are always kept
+ * enabled, and should not be idled even with no drivers.
+ */
+ for (i = 0; i < od->hwmods_cnt; i++)
+ if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
+ return 0;
+
+ if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
+ od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
+ if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
+ dev_warn(dev, "%s: enabled but no driver. Idling\n",
+ __func__);
+ omap_device_idle(pdev);
+ }
+ }
+
+ return 0;
+}
+
+static int __init omap_device_late_init(void)
+{
+ bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
+
+ return 0;
+}
+omap_late_initcall_sync(omap_device_late_init);