| /* |
| * omap_device implementation |
| * |
| * Copyright (C) 2009 Nokia Corporation |
| * Paul Walmsley |
| * |
| * Developed in collaboration with (alphabetical order): Benoit |
| * Cousson, Kevin Hilman, 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 either be |
| * a) implemented via arch-specific pointers in platform_data |
| * or |
| * b) implemented as a proper omap_bus/omap_device in Linux, no more |
| * platform_data func pointers |
| * |
| * |
| * Guidelines for usage by driver authors: |
| * |
| * 1. These functions are intended to be used by device drivers via |
| * function pointers in struct platform_data. As an example, |
| * omap_device_enable() should be passed to the driver as |
| * |
| * struct foo_driver_platform_data { |
| * ... |
| * int (*device_enable)(struct platform_device *pdev); |
| * ... |
| * } |
| * |
| * Note that the generic "device_enable" name is used, rather than |
| * "omap_device_enable". This is so other architectures can pass in their |
| * own enable/disable functions here. |
| * |
| * This should be populated during device setup: |
| * |
| * ... |
| * pdata->device_enable = omap_device_enable; |
| * ... |
| * |
| * 2. Drivers should first check to ensure the function pointer is not null |
| * before calling it, as in: |
| * |
| * if (pdata->device_enable) |
| * pdata->device_enable(pdev); |
| * |
| * This allows other architectures that don't use similar device_enable()/ |
| * device_shutdown() functions to execute normally. |
| * |
| * ... |
| * |
| * Suggested usage by device drivers: |
| * |
| * During device initialization: |
| * device_enable() |
| * |
| * During device idle: |
| * (save remaining device context if necessary) |
| * device_idle(); |
| * |
| * During device resume: |
| * device_enable(); |
| * (restore context if necessary) |
| * |
| * During device shutdown: |
| * device_shutdown() |
| * (device must be reinitialized at this point to use it again) |
| * |
| */ |
| #undef DEBUG |
| |
| #include <linux/kernel.h> |
| #include <linux/platform_device.h> |
| #include <linux/err.h> |
| #include <linux/io.h> |
| |
| #include <plat/omap_device.h> |
| #include <plat/omap_hwmod.h> |
| |
| /* These parameters are passed to _omap_device_{de,}activate() */ |
| #define USE_WAKEUP_LAT 0 |
| #define IGNORE_WAKEUP_LAT 1 |
| |
| /* XXX this should be moved into a separate file */ |
| #if defined(CONFIG_ARCH_OMAP2420) |
| # define OMAP_32KSYNCT_BASE 0x48004000 |
| #elif defined(CONFIG_ARCH_OMAP2430) |
| # define OMAP_32KSYNCT_BASE 0x49020000 |
| #elif defined(CONFIG_ARCH_OMAP3430) |
| # define OMAP_32KSYNCT_BASE 0x48320000 |
| #else |
| # error Unknown OMAP device |
| #endif |
| |
| /* Private functions */ |
| |
| /** |
| * _omap_device_activate - increase device readiness |
| * @od: struct omap_device * |
| * @ignore_lat: increase to latency target (0) or full readiness (1)? |
| * |
| * Increase readiness of omap_device @od (thus decreasing device |
| * wakeup latency, but consuming more power). If @ignore_lat is |
| * IGNORE_WAKEUP_LAT, make the omap_device fully active. Otherwise, |
| * if @ignore_lat is USE_WAKEUP_LAT, and the device's maximum wakeup |
| * latency is greater than the requested maximum wakeup latency, step |
| * backwards in the omap_device_pm_latency table to ensure the |
| * device's maximum wakeup latency is less than or equal to the |
| * requested maximum wakeup latency. Returns 0. |
| */ |
| static int _omap_device_activate(struct omap_device *od, u8 ignore_lat) |
| { |
| struct timespec a, b, c; |
| |
| pr_debug("omap_device: %s: activating\n", od->pdev.name); |
| |
| while (od->pm_lat_level > 0) { |
| struct omap_device_pm_latency *odpl; |
| unsigned long long act_lat = 0; |
| |
| od->pm_lat_level--; |
| |
| odpl = od->pm_lats + od->pm_lat_level; |
| |
| if (!ignore_lat && |
| (od->dev_wakeup_lat <= od->_dev_wakeup_lat_limit)) |
| break; |
| |
| read_persistent_clock(&a); |
| |
| /* XXX check return code */ |
| odpl->activate_func(od); |
| |
| read_persistent_clock(&b); |
| |
| c = timespec_sub(b, a); |
| act_lat = timespec_to_ns(&c) * NSEC_PER_USEC; |
| |
| pr_debug("omap_device: %s: pm_lat %d: activate: elapsed time " |
| "%llu usec\n", od->pdev.name, od->pm_lat_level, |
| act_lat); |
| |
| WARN(act_lat > odpl->activate_lat, "omap_device: %s.%d: " |
| "activate step %d took longer than expected (%llu > %d)\n", |
| od->pdev.name, od->pdev.id, od->pm_lat_level, |
| act_lat, odpl->activate_lat); |
| |
| od->dev_wakeup_lat -= odpl->activate_lat; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * _omap_device_deactivate - decrease device readiness |
| * @od: struct omap_device * |
| * @ignore_lat: decrease to latency target (0) or full inactivity (1)? |
| * |
| * Decrease readiness of omap_device @od (thus increasing device |
| * wakeup latency, but conserving power). If @ignore_lat is |
| * IGNORE_WAKEUP_LAT, make the omap_device fully inactive. Otherwise, |
| * if @ignore_lat is USE_WAKEUP_LAT, and the device's maximum wakeup |
| * latency is less than the requested maximum wakeup latency, step |
| * forwards in the omap_device_pm_latency table to ensure the device's |
| * maximum wakeup latency is less than or equal to the requested |
| * maximum wakeup latency. Returns 0. |
| */ |
| static int _omap_device_deactivate(struct omap_device *od, u8 ignore_lat) |
| { |
| struct timespec a, b, c; |
| |
| pr_debug("omap_device: %s: deactivating\n", od->pdev.name); |
| |
| while (od->pm_lat_level < od->pm_lats_cnt) { |
| struct omap_device_pm_latency *odpl; |
| unsigned long long deact_lat = 0; |
| |
| odpl = od->pm_lats + od->pm_lat_level; |
| |
| if (!ignore_lat && |
| ((od->dev_wakeup_lat + odpl->activate_lat) > |
| od->_dev_wakeup_lat_limit)) |
| break; |
| |
| read_persistent_clock(&a); |
| |
| /* XXX check return code */ |
| odpl->deactivate_func(od); |
| |
| read_persistent_clock(&b); |
| |
| c = timespec_sub(b, a); |
| deact_lat = timespec_to_ns(&c) * NSEC_PER_USEC; |
| |
| pr_debug("omap_device: %s: pm_lat %d: deactivate: elapsed time " |
| "%llu usec\n", od->pdev.name, od->pm_lat_level, |
| deact_lat); |
| |
| WARN(deact_lat > odpl->deactivate_lat, "omap_device: %s.%d: " |
| "deactivate step %d took longer than expected " |
| "(%llu > %d)\n", od->pdev.name, od->pdev.id, |
| od->pm_lat_level, deact_lat, odpl->deactivate_lat); |
| |
| od->dev_wakeup_lat += odpl->activate_lat; |
| |
| od->pm_lat_level++; |
| } |
| |
| return 0; |
| } |
| |
| static inline struct omap_device *_find_by_pdev(struct platform_device *pdev) |
| { |
| return container_of(pdev, struct omap_device, pdev); |
| } |
| |
| |
| /* Public functions for use by core code */ |
| |
| /** |
| * omap_device_count_resources - count number of struct resource entries needed |
| * @od: struct omap_device * |
| * |
| * Count the number of struct resource entries needed for this |
| * omap_device @od. Used by omap_device_build_ss() to determine how |
| * much memory to allocate before calling |
| * omap_device_fill_resources(). Returns the count. |
| */ |
| int omap_device_count_resources(struct omap_device *od) |
| { |
| struct omap_hwmod *oh; |
| int c = 0; |
| int i; |
| |
| for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) |
| c += omap_hwmod_count_resources(oh); |
| |
| pr_debug("omap_device: %s: counted %d total resources across %d " |
| "hwmods\n", od->pdev.name, c, od->hwmods_cnt); |
| |
| return c; |
| } |
| |
| /** |
| * omap_device_fill_resources - fill in array of struct resource |
| * @od: struct omap_device * |
| * @res: pointer to an array of struct resource to be filled in |
| * |
| * Populate one or more empty struct resource pointed to by @res with |
| * the resource data for this omap_device @od. Used by |
| * omap_device_build_ss() after calling omap_device_count_resources(). |
| * Ideally this function would not be needed at all. If omap_device |
| * replaces platform_device, then we can specify our own |
| * get_resource()/ get_irq()/etc functions that use the underlying |
| * omap_hwmod information. Or if platform_device is extended to use |
| * subarchitecture-specific function pointers, the various |
| * platform_device functions can simply call omap_device internal |
| * functions to get device resources. Hacking around the existing |
| * platform_device code wastes memory. Returns 0. |
| */ |
| int omap_device_fill_resources(struct omap_device *od, struct resource *res) |
| { |
| struct omap_hwmod *oh; |
| int c = 0; |
| int i, r; |
| |
| for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) { |
| r = omap_hwmod_fill_resources(oh, res); |
| res += r; |
| c += r; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * 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 |
| * @pm_lats: pointer to a omap_device_pm_latency array for this device |
| * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats |
| * |
| * 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 omap_device *omap_device_build(const char *pdev_name, int pdev_id, |
| struct omap_hwmod *oh, void *pdata, |
| int pdata_len, |
| struct omap_device_pm_latency *pm_lats, |
| int pm_lats_cnt) |
| { |
| struct omap_hwmod *ohs[] = { oh }; |
| |
| if (!oh) |
| return ERR_PTR(-EINVAL); |
| |
| return omap_device_build_ss(pdev_name, pdev_id, ohs, 1, pdata, |
| pdata_len, pm_lats, pm_lats_cnt); |
| } |
| |
| /** |
| * omap_device_build_ss - build and register 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 |
| * @pm_lats: pointer to a omap_device_pm_latency array for this device |
| * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats |
| * |
| * Convenience function for building and registering an omap_device |
| * subsystem record. Subsystem records consist of multiple |
| * omap_hwmods. This function in turn builds and registers a |
| * platform_device record. Returns an ERR_PTR() on error, or passes |
| * along the return value of omap_device_register(). |
| */ |
| struct omap_device *omap_device_build_ss(const char *pdev_name, int pdev_id, |
| struct omap_hwmod **ohs, int oh_cnt, |
| void *pdata, int pdata_len, |
| struct omap_device_pm_latency *pm_lats, |
| int pm_lats_cnt) |
| { |
| int ret = -ENOMEM; |
| struct omap_device *od; |
| char *pdev_name2; |
| struct resource *res = NULL; |
| int res_count; |
| struct omap_hwmod **hwmods; |
| |
| if (!ohs || oh_cnt == 0 || !pdev_name) |
| return ERR_PTR(-EINVAL); |
| |
| if (!pdata && pdata_len > 0) |
| return ERR_PTR(-EINVAL); |
| |
| pr_debug("omap_device: %s: building with %d hwmods\n", pdev_name, |
| oh_cnt); |
| |
| od = kzalloc(sizeof(struct omap_device), GFP_KERNEL); |
| if (!od) |
| return ERR_PTR(-ENOMEM); |
| |
| od->hwmods_cnt = oh_cnt; |
| |
| hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, |
| GFP_KERNEL); |
| if (!hwmods) |
| goto odbs_exit1; |
| |
| memcpy(hwmods, ohs, sizeof(struct omap_hwmod *) * oh_cnt); |
| od->hwmods = hwmods; |
| |
| pdev_name2 = kzalloc(strlen(pdev_name) + 1, GFP_KERNEL); |
| if (!pdev_name2) |
| goto odbs_exit2; |
| strcpy(pdev_name2, pdev_name); |
| |
| od->pdev.name = pdev_name2; |
| od->pdev.id = pdev_id; |
| |
| res_count = omap_device_count_resources(od); |
| if (res_count > 0) { |
| res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL); |
| if (!res) |
| goto odbs_exit3; |
| } |
| omap_device_fill_resources(od, res); |
| |
| od->pdev.num_resources = res_count; |
| od->pdev.resource = res; |
| |
| platform_device_add_data(&od->pdev, pdata, pdata_len); |
| |
| od->pm_lats = pm_lats; |
| od->pm_lats_cnt = pm_lats_cnt; |
| |
| ret = omap_device_register(od); |
| if (ret) |
| goto odbs_exit4; |
| |
| return od; |
| |
| odbs_exit4: |
| kfree(res); |
| odbs_exit3: |
| kfree(pdev_name2); |
| odbs_exit2: |
| kfree(hwmods); |
| odbs_exit1: |
| kfree(od); |
| |
| pr_err("omap_device: %s: build failed (%d)\n", pdev_name, ret); |
| |
| return ERR_PTR(ret); |
| } |
| |
| /** |
| * 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 omap_device *od) |
| { |
| pr_debug("omap_device: %s: registering\n", od->pdev.name); |
| |
| return platform_device_register(&od->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 |
| * (through platform_data function pointers) where they would normally |
| * enable clocks, etc. Returns -EINVAL if called when the omap_device |
| * is already enabled, or passes along the return value of |
| * _omap_device_activate(). |
| */ |
| int omap_device_enable(struct platform_device *pdev) |
| { |
| int ret; |
| struct omap_device *od; |
| |
| od = _find_by_pdev(pdev); |
| |
| if (od->_state == OMAP_DEVICE_STATE_ENABLED) { |
| WARN(1, "omap_device: %s.%d: omap_device_enable() called from " |
| "invalid state\n", od->pdev.name, od->pdev.id); |
| return -EINVAL; |
| } |
| |
| /* Enable everything if we're enabling this device from scratch */ |
| if (od->_state == OMAP_DEVICE_STATE_UNKNOWN) |
| od->pm_lat_level = od->pm_lats_cnt; |
| |
| ret = _omap_device_activate(od, IGNORE_WAKEUP_LAT); |
| |
| od->dev_wakeup_lat = 0; |
| od->_dev_wakeup_lat_limit = UINT_MAX; |
| 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 by calling as many .deactivate_func() entries |
| * in the omap_device's pm_lats table as is possible without exceeding |
| * the device's maximum wakeup latency limit, pm_lat_limit. Device |
| * drivers should call this function (through platform_data function |
| * pointers) where they would normally disable clocks after operations |
| * complete, etc.. Returns -EINVAL if the omap_device is not |
| * currently enabled, or passes along the return value of |
| * _omap_device_deactivate(). |
| */ |
| int omap_device_idle(struct platform_device *pdev) |
| { |
| int ret; |
| struct omap_device *od; |
| |
| od = _find_by_pdev(pdev); |
| |
| if (od->_state != OMAP_DEVICE_STATE_ENABLED) { |
| WARN(1, "omap_device: %s.%d: omap_device_idle() called from " |
| "invalid state\n", od->pdev.name, od->pdev.id); |
| return -EINVAL; |
| } |
| |
| ret = _omap_device_deactivate(od, USE_WAKEUP_LAT); |
| |
| od->_state = OMAP_DEVICE_STATE_IDLE; |
| |
| return ret; |
| } |
| |
| /** |
| * omap_device_shutdown - shut down an omap_device |
| * @od: struct omap_device * to shut down |
| * |
| * Shut down omap_device @od by calling all .deactivate_func() entries |
| * in the omap_device's pm_lats table and then shutting down all of |
| * the underlying omap_hwmods. Used when a device is being "removed" |
| * or a device driver is being unloaded. Returns -EINVAL if the |
| * omap_device is not currently enabled or idle, or passes along the |
| * return value of _omap_device_deactivate(). |
| */ |
| int omap_device_shutdown(struct platform_device *pdev) |
| { |
| int ret, i; |
| struct omap_device *od; |
| struct omap_hwmod *oh; |
| |
| od = _find_by_pdev(pdev); |
| |
| if (od->_state != OMAP_DEVICE_STATE_ENABLED && |
| od->_state != OMAP_DEVICE_STATE_IDLE) { |
| WARN(1, "omap_device: %s.%d: omap_device_shutdown() called " |
| "from invalid state\n", od->pdev.name, od->pdev.id); |
| return -EINVAL; |
| } |
| |
| ret = _omap_device_deactivate(od, IGNORE_WAKEUP_LAT); |
| |
| for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) |
| omap_hwmod_shutdown(oh); |
| |
| od->_state = OMAP_DEVICE_STATE_SHUTDOWN; |
| |
| return ret; |
| } |
| |
| /** |
| * omap_device_align_pm_lat - activate/deactivate device to match wakeup lat lim |
| * @od: struct omap_device * |
| * |
| * When a device's maximum wakeup latency limit changes, call some of |
| * the .activate_func or .deactivate_func function pointers in the |
| * omap_device's pm_lats array to ensure that the device's maximum |
| * wakeup latency is less than or equal to the new latency limit. |
| * Intended to be called by OMAP PM code whenever a device's maximum |
| * wakeup latency limit changes (e.g., via |
| * omap_pm_set_dev_wakeup_lat()). Returns 0 if nothing needs to be |
| * done (e.g., if the omap_device is not currently idle, or if the |
| * wakeup latency is already current with the new limit) or passes |
| * along the return value of _omap_device_deactivate() or |
| * _omap_device_activate(). |
| */ |
| int omap_device_align_pm_lat(struct platform_device *pdev, |
| u32 new_wakeup_lat_limit) |
| { |
| int ret = -EINVAL; |
| struct omap_device *od; |
| |
| od = _find_by_pdev(pdev); |
| |
| if (new_wakeup_lat_limit == od->dev_wakeup_lat) |
| return 0; |
| |
| od->_dev_wakeup_lat_limit = new_wakeup_lat_limit; |
| |
| if (od->_state != OMAP_DEVICE_STATE_IDLE) |
| return 0; |
| else if (new_wakeup_lat_limit > od->dev_wakeup_lat) |
| ret = _omap_device_deactivate(od, USE_WAKEUP_LAT); |
| else if (new_wakeup_lat_limit < od->dev_wakeup_lat) |
| ret = _omap_device_activate(od, USE_WAKEUP_LAT); |
| |
| return ret; |
| } |
| |
| /** |
| * omap_device_get_pwrdm - return the powerdomain * associated with @od |
| * @od: struct omap_device * |
| * |
| * Return the powerdomain associated with the first underlying |
| * omap_hwmod for this omap_device. Intended for use by core OMAP PM |
| * code. Returns NULL on error or a struct powerdomain * upon |
| * success. |
| */ |
| struct powerdomain *omap_device_get_pwrdm(struct omap_device *od) |
| { |
| /* |
| * XXX Assumes that all omap_hwmod powerdomains are identical. |
| * This may not necessarily be true. There should be a sanity |
| * check in here to WARN() if any difference appears. |
| */ |
| if (!od->hwmods_cnt) |
| return NULL; |
| |
| return omap_hwmod_get_pwrdm(od->hwmods[0]); |
| } |
| |
| /* |
| * Public functions intended for use in omap_device_pm_latency |
| * .activate_func and .deactivate_func function pointers |
| */ |
| |
| /** |
| * omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods |
| * @od: struct omap_device *od |
| * |
| * Enable all underlying hwmods. Returns 0. |
| */ |
| int omap_device_enable_hwmods(struct omap_device *od) |
| { |
| struct omap_hwmod *oh; |
| int i; |
| |
| for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) |
| omap_hwmod_enable(oh); |
| |
| /* XXX pass along return value here? */ |
| return 0; |
| } |
| |
| /** |
| * omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods |
| * @od: struct omap_device *od |
| * |
| * Idle all underlying hwmods. Returns 0. |
| */ |
| int omap_device_idle_hwmods(struct omap_device *od) |
| { |
| struct omap_hwmod *oh; |
| int i; |
| |
| for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) |
| omap_hwmod_idle(oh); |
| |
| /* XXX pass along return value here? */ |
| return 0; |
| } |
| |
| /** |
| * omap_device_disable_clocks - disable all main and interface clocks |
| * @od: struct omap_device *od |
| * |
| * Disable the main functional clock and interface clock for all of the |
| * omap_hwmods associated with the omap_device. Returns 0. |
| */ |
| int omap_device_disable_clocks(struct omap_device *od) |
| { |
| struct omap_hwmod *oh; |
| int i; |
| |
| for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) |
| omap_hwmod_disable_clocks(oh); |
| |
| /* XXX pass along return value here? */ |
| return 0; |
| } |
| |
| /** |
| * omap_device_enable_clocks - enable all main and interface clocks |
| * @od: struct omap_device *od |
| * |
| * Enable the main functional clock and interface clock for all of the |
| * omap_hwmods associated with the omap_device. Returns 0. |
| */ |
| int omap_device_enable_clocks(struct omap_device *od) |
| { |
| struct omap_hwmod *oh; |
| int i; |
| |
| for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) |
| omap_hwmod_enable_clocks(oh); |
| |
| /* XXX pass along return value here? */ |
| return 0; |
| } |