diff options
Diffstat (limited to 'drivers/amba/bus.c')
| -rw-r--r-- | drivers/amba/bus.c | 382 |
1 files changed, 313 insertions, 69 deletions
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 6b94fb7be5f..3cf61a127ee 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -12,16 +12,18 @@ #include <linux/device.h> #include <linux/string.h> #include <linux/slab.h> +#include <linux/io.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> #include <linux/amba/bus.h> +#include <linux/sizes.h> -#include <asm/io.h> -#include <asm/sizes.h> +#include <asm/irq.h> -#define to_amba_device(d) container_of(d, struct amba_device, dev) #define to_amba_driver(d) container_of(d, struct amba_driver, drv) -static struct amba_id * -amba_lookup(struct amba_id *table, struct amba_device *dev) +static const struct amba_id * +amba_lookup(const struct amba_id *table, struct amba_device *dev) { int ret = 0; @@ -43,37 +45,17 @@ static int amba_match(struct device *dev, struct device_driver *drv) return amba_lookup(pcdrv->id_table, pcdev) != NULL; } -#ifdef CONFIG_HOTPLUG static int amba_uevent(struct device *dev, struct kobj_uevent_env *env) { struct amba_device *pcdev = to_amba_device(dev); int retval = 0; retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid); - return retval; -} -#else -#define amba_uevent NULL -#endif - -static int amba_suspend(struct device *dev, pm_message_t state) -{ - struct amba_driver *drv = to_amba_driver(dev->driver); - int ret = 0; - - if (dev->driver && drv->suspend) - ret = drv->suspend(to_amba_device(dev), state); - return ret; -} - -static int amba_resume(struct device *dev) -{ - struct amba_driver *drv = to_amba_driver(dev->driver); - int ret = 0; + if (retval) + return retval; - if (dev->driver && drv->resume) - ret = drv->resume(to_amba_device(dev)); - return ret; + retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid); + return retval; } #define amba_attr_func(name,fmt,arg...) \ @@ -101,17 +83,63 @@ static struct device_attribute amba_dev_attrs[] = { __ATTR_NULL, }; +#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) + 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) { + 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 + +static const struct dev_pm_ops amba_pm = { + .suspend = pm_generic_suspend, + .resume = pm_generic_resume, + .freeze = pm_generic_freeze, + .thaw = pm_generic_thaw, + .poweroff = pm_generic_poweroff, + .restore = pm_generic_restore, + SET_PM_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". */ -static struct bus_type amba_bustype = { +struct bus_type amba_bustype = { .name = "amba", .dev_attrs = amba_dev_attrs, .match = amba_match, .uevent = amba_uevent, - .suspend = amba_suspend, - .resume = amba_resume, + .pm = &amba_pm, }; static int __init amba_init(void) @@ -121,6 +149,27 @@ static int __init amba_init(void) postcore_initcall(amba_init); +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); +} + /* * These are the device model conversion veneers; they convert the * device model structures to our more specific structures. @@ -129,17 +178,50 @@ static int amba_probe(struct device *dev) { struct amba_device *pcdev = to_amba_device(dev); struct amba_driver *pcdrv = to_amba_driver(dev->driver); - struct amba_id *id; + const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev); + int ret; + + do { + 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; - id = amba_lookup(pcdrv->id_table, pcdev); + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + pm_runtime_put_noidle(dev); - return pcdrv->probe(pcdev, id); + amba_put_disable_pclk(pcdev); + } while (0); + + return ret; } static int amba_remove(struct device *dev) { + struct amba_device *pcdev = to_amba_device(dev); struct amba_driver *drv = to_amba_driver(dev->driver); - return drv->remove(to_amba_device(dev)); + int ret; + + pm_runtime_get_sync(dev); + ret = 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); + + return ret; } static void amba_shutdown(struct device *dev) @@ -192,60 +274,79 @@ static void amba_device_release(struct device *dev) } /** - * amba_device_register - register an AMBA device - * @dev: AMBA device to register - * @parent: parent memory resource + * 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 * - * Setup the AMBA device, reading the cell ID if present. - * Claim the resource, and register the AMBA device with - * the Linux device manager. + * 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_register(struct amba_device *dev, struct resource *parent) +int amba_device_add(struct amba_device *dev, struct resource *parent) { - u32 pid, cid; + u32 size; void __iomem *tmp; int i, ret; - dev->dev.release = amba_device_release; - dev->dev.bus = &amba_bustype; - dev->dev.dma_mask = &dev->dma_mask; - dev->res.name = dev->dev.bus_id; - - if (!dev->dev.coherent_dma_mask && dev->dma_mask) - dev_warn(&dev->dev, "coherent dma mask is unset\n"); + WARN_ON(dev->irq[0] == (unsigned int)-1); + WARN_ON(dev->irq[1] == (unsigned int)-1); ret = request_resource(parent, &dev->res); if (ret) goto err_out; - tmp = ioremap(dev->res.start, SZ_4K); + /* Hard-coded primecell ID instead of plug-n-play */ + if (dev->periphid != 0) + goto skip_probe; + + /* + * Dynamically calculate the size of the resource + * and use this for iomap + */ + size = resource_size(&dev->res); + tmp = ioremap(dev->res.start, size); if (!tmp) { ret = -ENOMEM; goto err_release; } - for (pid = 0, i = 0; i < 4; i++) - pid |= (readl(tmp + 0xfe0 + 4 * i) & 255) << (i * 8); - for (cid = 0, i = 0; i < 4; i++) - cid |= (readl(tmp + 0xff0 + 4 * i) & 255) << (i * 8); + ret = amba_get_enable_pclk(dev); + if (ret == 0) { + u32 pid, cid; - iounmap(tmp); + /* + * 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 == 0xb105f00d) - dev->periphid = pid; + amba_put_disable_pclk(dev); - if (!dev->periphid) { - ret = -ENODEV; - goto err_release; + if (cid == AMBA_CID) + dev->periphid = pid; + + if (!dev->periphid) + ret = -ENODEV; } - ret = device_register(&dev->dev); + iounmap(tmp); + + if (ret) + goto err_release; + + skip_probe: + ret = device_add(&dev->dev); if (ret) goto err_release; - if (dev->irq[0] != NO_IRQ) + if (dev->irq[0]) ret = device_create_file(&dev->dev, &dev_attr_irq0); - if (ret == 0 && dev->irq[1] != NO_IRQ) + if (ret == 0 && dev->irq[1]) ret = device_create_file(&dev->dev, &dev_attr_irq1); if (ret == 0) return ret; @@ -257,6 +358,143 @@ int amba_device_register(struct amba_device *dev, struct resource *parent) err_out: return ret; } +EXPORT_SYMBOL_GPL(amba_device_add); + +static struct amba_device * +amba_aphb_device_add(struct device *parent, const char *name, + resource_size_t base, size_t size, int irq1, int irq2, + void *pdata, unsigned int periphid, u64 dma_mask, + struct resource *resbase) +{ + struct amba_device *dev; + int ret; + + dev = amba_device_alloc(name, base, size); + if (!dev) + return ERR_PTR(-ENOMEM); + + dev->dev.coherent_dma_mask = dma_mask; + dev->irq[0] = irq1; + dev->irq[1] = irq2; + dev->periphid = periphid; + dev->dev.platform_data = pdata; + dev->dev.parent = parent; + + ret = amba_device_add(dev, resbase); + if (ret) { + amba_device_put(dev); + return ERR_PTR(ret); + } + + return dev; +} + +struct amba_device * +amba_apb_device_add(struct device *parent, const char *name, + resource_size_t base, size_t size, int irq1, int irq2, + void *pdata, unsigned int periphid) +{ + return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, + periphid, 0, &iomem_resource); +} +EXPORT_SYMBOL_GPL(amba_apb_device_add); + +struct amba_device * +amba_ahb_device_add(struct device *parent, const char *name, + resource_size_t base, size_t size, int irq1, int irq2, + void *pdata, unsigned int periphid) +{ + return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, + periphid, ~0ULL, &iomem_resource); +} +EXPORT_SYMBOL_GPL(amba_ahb_device_add); + +struct amba_device * +amba_apb_device_add_res(struct device *parent, const char *name, + resource_size_t base, size_t size, int irq1, + int irq2, void *pdata, unsigned int periphid, + struct resource *resbase) +{ + return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, + periphid, 0, resbase); +} +EXPORT_SYMBOL_GPL(amba_apb_device_add_res); + +struct amba_device * +amba_ahb_device_add_res(struct device *parent, const char *name, + resource_size_t base, size_t size, int irq1, + int irq2, void *pdata, unsigned int periphid, + struct resource *resbase) +{ + return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, + periphid, ~0ULL, resbase); +} +EXPORT_SYMBOL_GPL(amba_ahb_device_add_res); + + +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->res.name = dev_name(&dev->dev); +} + +/** + * 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(sizeof(*dev), GFP_KERNEL); + 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); +} + +/** + * 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 @@ -293,7 +531,7 @@ static int amba_find_match(struct device *dev, void *data) if (d->parent) r &= d->parent == dev->parent; if (d->busid) - r &= strcmp(dev->bus_id, d->busid) == 0; + r &= strcmp(dev_name(dev), d->busid) == 0; if (r) { get_device(dev); @@ -342,25 +580,31 @@ amba_find_device(const char *busid, struct device *parent, unsigned int id, int amba_request_regions(struct amba_device *dev, const char *name) { int ret = 0; + u32 size; if (!name) name = dev->dev.driver->name; - if (!request_mem_region(dev->res.start, SZ_4K, name)) + size = resource_size(&dev->res); + + if (!request_mem_region(dev->res.start, size, name)) ret = -EBUSY; return ret; } /** - * amba_release_regions - release mem regions assoicated with device + * 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) { - release_mem_region(dev->res.start, SZ_4K); + u32 size; + + size = resource_size(&dev->res); + release_mem_region(dev->res.start, size); } EXPORT_SYMBOL(amba_driver_register); |
