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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#define to_amba_driver(d) container_of_const(d, struct amba_driver, drv)
/* called on periphid match and class 0x9 coresight device. */static intamba_cs_uci_id_match(const struct amba_id *table, struct amba_device *dev){ int ret = 0; struct amba_cs_uci_id *uci;
uci = table->data;
/* no table data or zero mask - return match on periphid */ if (!uci || (uci->devarch_mask == 0)) return 1;
/* test against read devtype and masked devarch value */ ret = (dev->uci.devtype == uci->devtype) && ((dev->uci.devarch & uci->devarch_mask) == uci->devarch); return ret;}
static const struct amba_id *amba_lookup(const struct amba_id *table, struct amba_device *dev){ while (table->mask) { if (((dev->periphid & table->mask) == table->id) && ((dev->cid != CORESIGHT_CID) || (amba_cs_uci_id_match(table, dev)))) return table; table++; } return NULL;}
static int amba_get_enable_pclk(struct amba_device *pcdev){ int ret;
pcdev->pclk = clk_get(&pcdev->dev, "apb_pclk"); if (IS_ERR(pcdev->pclk)) return PTR_ERR(pcdev->pclk);
ret = clk_prepare_enable(pcdev->pclk); if (ret) clk_put(pcdev->pclk);
return ret;}
static void amba_put_disable_pclk(struct amba_device *pcdev){ clk_disable_unprepare(pcdev->pclk); clk_put(pcdev->pclk);}
#define amba_attr_func(name,fmt,arg...) \static ssize_t name##_show(struct device *_dev, \ struct device_attribute *attr, char *buf) \{ \ struct amba_device *dev = to_amba_device(_dev); \ return sprintf(buf, fmt, arg); \} \static DEVICE_ATTR_RO(name)
amba_attr_func(id, "%08x\n", dev->periphid);amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n", (unsigned long long)dev->res.start, (unsigned long long)dev->res.end, dev->res.flags);
static struct attribute *amba_dev_attrs[] = { &dev_attr_id.attr, &dev_attr_resource.attr, NULL,};ATTRIBUTE_GROUPS(amba_dev);
static int amba_read_periphid(struct amba_device *dev){ struct reset_control *rstc; u32 size, pid, cid; void __iomem *tmp; int i, ret;
ret = dev_pm_domain_attach(&dev->dev, PD_FLAG_ATTACH_POWER_ON); if (ret) { dev_dbg(&dev->dev, "can't get PM domain: %d\n", ret); goto err_out; }
ret = amba_get_enable_pclk(dev); if (ret) { dev_dbg(&dev->dev, "can't get pclk: %d\n", ret); goto err_pm; }
/* * Find reset control(s) of the amba bus and de-assert them. */ rstc = of_reset_control_array_get_optional_shared(dev->dev.of_node); if (IS_ERR(rstc)) { ret = PTR_ERR(rstc); if (ret != -EPROBE_DEFER) dev_err(&dev->dev, "can't get reset: %d\n", ret); goto err_clk; } reset_control_deassert(rstc); reset_control_put(rstc);
size = resource_size(&dev->res); tmp = ioremap(dev->res.start, size); if (!tmp) { ret = -ENOMEM; goto err_clk; }
/* * Read pid and cid based on size of resource * they are located at end of region */ for (pid = 0, i = 0; i < 4; i++) pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) << (i * 8); for (cid = 0, i = 0; i < 4; i++) cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) << (i * 8);
if (cid == CORESIGHT_CID) { /* set the base to the start of the last 4k block */ void __iomem *csbase = tmp + size - 4096;
dev->uci.devarch = readl(csbase + UCI_REG_DEVARCH_OFFSET); dev->uci.devtype = readl(csbase + UCI_REG_DEVTYPE_OFFSET) & 0xff; }
if (cid == AMBA_CID || cid == CORESIGHT_CID) { dev->periphid = pid; dev->cid = cid; }
if (!dev->periphid) ret = -ENODEV;
iounmap(tmp);
err_clk: amba_put_disable_pclk(dev);err_pm: dev_pm_domain_detach(&dev->dev, true);err_out: return ret;}
static int amba_match(struct device *dev, const struct device_driver *drv){ struct amba_device *pcdev = to_amba_device(dev); const struct amba_driver *pcdrv = to_amba_driver(drv); int ret;
mutex_lock(&pcdev->periphid_lock); if (!pcdev->periphid) { ret = amba_read_periphid(pcdev);
/* * Returning any error other than -EPROBE_DEFER from bus match * can cause driver registration failure. So, if there's a * permanent failure in reading pid and cid, simply map it to * -EPROBE_DEFER. */ if (ret) { mutex_unlock(&pcdev->periphid_lock); return -EPROBE_DEFER; } dev_set_uevent_suppress(dev, false); kobject_uevent(&dev->kobj, KOBJ_ADD); } mutex_unlock(&pcdev->periphid_lock);
/* When driver_override is set, only bind to the matching driver */ ret = device_match_driver_override(dev, drv); if (ret >= 0) return ret;
return amba_lookup(pcdrv->id_table, pcdev) != NULL;}
static int amba_uevent(const struct device *dev, struct kobj_uevent_env *env){ const struct amba_device *pcdev = to_amba_device(dev); int retval = 0;
retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid); if (retval) return retval;
retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid); return retval;}
static int of_amba_device_decode_irq(struct amba_device *dev){ struct device_node *node = dev->dev.of_node; int i, irq = 0;
if (IS_ENABLED(CONFIG_OF_IRQ) && node) { /* Decode the IRQs and address ranges */ for (i = 0; i < AMBA_NR_IRQS; i++) { irq = of_irq_get(node, i); if (irq < 0) { if (irq == -EPROBE_DEFER) return irq; irq = 0; }
dev->irq[i] = irq; } }
return 0;}
/* * These are the device model conversion veneers; they convert the * device model structures to our more specific structures. */static int amba_probe(struct device *dev){ struct amba_device *pcdev = to_amba_device(dev); struct amba_driver *pcdrv = to_amba_driver(dev->driver); const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev); int ret;
do { ret = of_amba_device_decode_irq(pcdev); if (ret) break;
ret = of_clk_set_defaults(dev->of_node, false); if (ret < 0) break;
ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON | PD_FLAG_DETACH_POWER_OFF); if (ret) break;
ret = amba_get_enable_pclk(pcdev); if (ret) break;
pm_runtime_get_noresume(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev);
ret = pcdrv->probe(pcdev, id); if (ret == 0) break;
pm_runtime_disable(dev); pm_runtime_set_suspended(dev); pm_runtime_put_noidle(dev);
amba_put_disable_pclk(pcdev); } while (0);
return ret;}
static void amba_remove(struct device *dev){ struct amba_device *pcdev = to_amba_device(dev); struct amba_driver *drv = to_amba_driver(dev->driver);
pm_runtime_get_sync(dev); if (drv->remove) drv->remove(pcdev); pm_runtime_put_noidle(dev);
/* Undo the runtime PM settings in amba_probe() */ pm_runtime_disable(dev); pm_runtime_set_suspended(dev); pm_runtime_put_noidle(dev);
amba_put_disable_pclk(pcdev);}
static void amba_shutdown(struct device *dev){ struct amba_driver *drv;
if (!dev->driver) return;
drv = to_amba_driver(dev->driver); if (drv->shutdown) drv->shutdown(to_amba_device(dev));}
static int amba_dma_configure(struct device *dev){ struct amba_driver *drv = to_amba_driver(dev->driver); enum dev_dma_attr attr; int ret = 0;
if (dev->of_node) { ret = of_dma_configure(dev, dev->of_node, true); } else if (has_acpi_companion(dev)) { attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode)); ret = acpi_dma_configure(dev, attr); }
/* @drv may not be valid when we're called from the IOMMU layer */ if (!ret && dev->driver && !drv->driver_managed_dma) { ret = iommu_device_use_default_domain(dev); if (ret) arch_teardown_dma_ops(dev); }
return ret;}
static void amba_dma_cleanup(struct device *dev){ struct amba_driver *drv = to_amba_driver(dev->driver);
if (!drv->driver_managed_dma) iommu_device_unuse_default_domain(dev);}
#ifdef CONFIG_PM/* * Hooks to provide runtime PM of the pclk (bus clock). It is safe to * enable/disable the bus clock at runtime PM suspend/resume as this * does not result in loss of context. */static int amba_pm_runtime_suspend(struct device *dev){ struct amba_device *pcdev = to_amba_device(dev); int ret = pm_generic_runtime_suspend(dev);
if (ret == 0 && dev->driver) { if (pm_runtime_is_irq_safe(dev)) clk_disable(pcdev->pclk); else clk_disable_unprepare(pcdev->pclk); }
return ret;}
static int amba_pm_runtime_resume(struct device *dev){ struct amba_device *pcdev = to_amba_device(dev); int ret;
if (dev->driver) { if (pm_runtime_is_irq_safe(dev)) ret = clk_enable(pcdev->pclk); else ret = clk_prepare_enable(pcdev->pclk); /* Failure is probably fatal to the system, but... */ if (ret) return ret; }
return pm_generic_runtime_resume(dev);}#endif /* CONFIG_PM */
static const struct dev_pm_ops amba_pm = { SET_RUNTIME_PM_OPS( amba_pm_runtime_suspend, amba_pm_runtime_resume, NULL )};
/* * Primecells are part of the Advanced Microcontroller Bus Architecture, * so we call the bus "amba". * DMA configuration for platform and AMBA bus is same. So here we reuse * platform's DMA config routine. */const struct bus_type amba_bustype = { .name = "amba", .dev_groups = amba_dev_groups, .driver_override = true, .match = amba_match, .uevent = amba_uevent, .probe = amba_probe, .remove = amba_remove, .shutdown = amba_shutdown, .dma_configure = amba_dma_configure, .dma_cleanup = amba_dma_cleanup, .pm = &amba_pm,};EXPORT_SYMBOL_GPL(amba_bustype);
bool dev_is_amba(const struct device *dev){ return dev->bus == &amba_bustype;}EXPORT_SYMBOL_GPL(dev_is_amba);
static int __init amba_init(void){ return bus_register(&amba_bustype);}
postcore_initcall(amba_init);
static int amba_proxy_probe(struct amba_device *adev, const struct amba_id *id){ WARN(1, "Stub driver should never match any device.\n"); return -ENODEV;}
static const struct amba_id amba_stub_drv_ids[] = { { 0, 0 },};
static struct amba_driver amba_proxy_drv = { .drv = { .name = "amba-proxy", }, .probe = amba_proxy_probe, .id_table = amba_stub_drv_ids,};
static int __init amba_stub_drv_init(void){ if (!IS_ENABLED(CONFIG_MODULES)) return 0;
/* * The amba_match() function will get called only if there is at least * one amba driver registered. If all amba drivers are modules and are * only loaded based on uevents, then we'll hit a chicken-and-egg * situation where amba_match() is waiting on drivers and drivers are * waiting on amba_match(). So, register a stub driver to make sure * amba_match() is called even if no amba driver has been registered. */ return __amba_driver_register(&amba_proxy_drv, NULL);}late_initcall_sync(amba_stub_drv_init);
/** * __amba_driver_register - register an AMBA device driver * @drv: amba device driver structure * @owner: owning module/driver * * Register an AMBA device driver with the Linux device model * core. If devices pre-exist, the drivers probe function will * be called. */int __amba_driver_register(struct amba_driver *drv, struct module *owner){ if (!drv->probe) return -EINVAL;
drv->drv.owner = owner; drv->drv.bus = &amba_bustype;
return driver_register(&drv->drv);}EXPORT_SYMBOL(__amba_driver_register);
/** * amba_driver_unregister - remove an AMBA device driver * @drv: AMBA device driver structure to remove * * Unregister an AMBA device driver from the Linux device * model. The device model will call the drivers remove function * for each device the device driver is currently handling. */void amba_driver_unregister(struct amba_driver *drv){ driver_unregister(&drv->drv);}EXPORT_SYMBOL(amba_driver_unregister);
static void amba_device_release(struct device *dev){ struct amba_device *d = to_amba_device(dev);
fwnode_handle_put(dev_fwnode(&d->dev)); if (d->res.parent) release_resource(&d->res); mutex_destroy(&d->periphid_lock); kfree(d);}
/** * amba_device_add - add a previously allocated AMBA device structure * @dev: AMBA device allocated by amba_device_alloc * @parent: resource parent for this devices resources * * Claim the resource, and read the device cell ID if not already * initialized. Register the AMBA device with the Linux device * manager. */int amba_device_add(struct amba_device *dev, struct resource *parent){ int ret;
fwnode_handle_get(dev_fwnode(&dev->dev));
ret = request_resource(parent, &dev->res); if (ret) return ret;
/* If primecell ID isn't hard-coded, figure it out */ if (!dev->periphid) { /* * AMBA device uevents require reading its pid and cid * registers. To do this, the device must be on, clocked and * out of reset. However in some cases those resources might * not yet be available. If that's the case, we suppress the * generation of uevents until we can read the pid and cid * registers. See also amba_match(). */ if (amba_read_periphid(dev)) dev_set_uevent_suppress(&dev->dev, true); }
ret = device_add(&dev->dev); if (ret) release_resource(&dev->res);
return ret;}EXPORT_SYMBOL_GPL(amba_device_add);
static void amba_device_initialize(struct amba_device *dev, const char *name){ device_initialize(&dev->dev); if (name) dev_set_name(&dev->dev, "%s", name); dev->dev.release = amba_device_release; dev->dev.bus = &amba_bustype; dev->dev.dma_mask = &dev->dev.coherent_dma_mask; dev->dev.dma_parms = &dev->dma_parms; dev->res.name = dev_name(&dev->dev); mutex_init(&dev->periphid_lock);}
/** * amba_device_alloc - allocate an AMBA device * @name: sysfs name of the AMBA device * @base: base of AMBA device * @size: size of AMBA device * * Allocate and initialize an AMBA device structure. Returns %NULL * on failure. */struct amba_device *amba_device_alloc(const char *name, resource_size_t base, size_t size){ struct amba_device *dev;
dev = kzalloc_obj(*dev); if (dev) { amba_device_initialize(dev, name); dev->res.start = base; dev->res.end = base + size - 1; dev->res.flags = IORESOURCE_MEM; }
return dev;}EXPORT_SYMBOL_GPL(amba_device_alloc);
/** * amba_device_register - register an AMBA device * @dev: AMBA device to register * @parent: parent memory resource * * Setup the AMBA device, reading the cell ID if present. * Claim the resource, and register the AMBA device with * the Linux device manager. */int amba_device_register(struct amba_device *dev, struct resource *parent){ amba_device_initialize(dev, dev->dev.init_name); dev->dev.init_name = NULL;
return amba_device_add(dev, parent);}EXPORT_SYMBOL(amba_device_register);
/** * amba_device_put - put an AMBA device * @dev: AMBA device to put */void amba_device_put(struct amba_device *dev){ put_device(&dev->dev);}EXPORT_SYMBOL_GPL(amba_device_put);
/** * amba_device_unregister - unregister an AMBA device * @dev: AMBA device to remove * * Remove the specified AMBA device from the Linux device * manager. All files associated with this object will be * destroyed, and device drivers notified that the device has * been removed. The AMBA device's resources including * the amba_device structure will be freed once all * references to it have been dropped. */void amba_device_unregister(struct amba_device *dev){ device_unregister(&dev->dev);}EXPORT_SYMBOL(amba_device_unregister);
/** * amba_request_regions - request all mem regions associated with device * @dev: amba_device structure for device * @name: name, or NULL to use driver name */int amba_request_regions(struct amba_device *dev, const char *name){ int ret = 0; u32 size;
if (!name) name = dev->dev.driver->name;
size = resource_size(&dev->res);
if (!request_mem_region(dev->res.start, size, name)) ret = -EBUSY;
return ret;}EXPORT_SYMBOL(amba_request_regions);
/** * amba_release_regions - release mem regions associated with device * @dev: amba_device structure for device * * Release regions claimed by a successful call to amba_request_regions. */void amba_release_regions(struct amba_device *dev){ u32 size;
size = resource_size(&dev->res); release_mem_region(dev->res.start, size);}EXPORT_SYMBOL(amba_release_regions);