linux/arch/arm/mach-omap2/omap_device.c

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/*
* 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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/pm_runtime.h>
#include <linux/of.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;
struct clk_lookup *l;
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_warn(&od->pdev->dev,
"alias %s already exists\n", clk_alias);
clk_put(r);
return;
}
r = clk_get(NULL, clk_name);
if (IS_ERR(r)) {
dev_err(&od->pdev->dev,
"clk_get for %s failed\n", clk_name);
return;
}
l = clkdev_alloc(r, clk_alias, dev_name(&od->pdev->dev));
if (!l) {
dev_err(&od->pdev->dev,
"clkdev_alloc for %s failed\n", clk_alias);
return;
}
clkdev_add(l);
}
/**
* _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;
const char *oh_name;
int oh_cnt, i, ret = 0;
bool device_active = 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;
}
hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, 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);
}
pdev->dev.pm_domain = &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)
pdev->dev.pm_domain = &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;
switch (event) {
case BUS_NOTIFY_DEL_DEVICE:
if (pdev->archdata.od)
omap_device_delete(pdev->archdata.od);
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 i;
for (i = 0; i < od->hwmods_cnt; i++)
omap_hwmod_enable(od->hwmods[i]);
/* 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.
*/
static int _omap_device_idle_hwmods(struct omap_device *od)
{
int i;
for (i = 0; i < od->hwmods_cnt; i++)
omap_hwmod_idle(od->hwmods[i]);
/* XXX pass along return value here? */
return 0;
}
/* 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 assoiated 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_count_resources - count number of struct resource entries needed
* @od: struct omap_device *
* @flags: Type of resources to include when counting (IRQ/DMA/MEM)
*
* 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.
*/
static int omap_device_count_resources(struct omap_device *od,
unsigned long flags)
{
int c = 0;
int i;
for (i = 0; i < od->hwmods_cnt; i++)
c += omap_hwmod_count_resources(od->hwmods[i], flags);
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.
*/
static int omap_device_fill_resources(struct omap_device *od,
struct resource *res)
{
int i, r;
for (i = 0; i < od->hwmods_cnt; i++) {
r = omap_hwmod_fill_resources(od->hwmods[i], res);
res += r;
}
return 0;
}
/**
* _od_fill_dma_resources - fill in array of struct resource with dma resources
* @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 dma resource data for this omap_device @od. Used by
* omap_device_alloc() after calling omap_device_count_resources().
*
* Ideally this function would not be needed at all. If we have
* mechanism to get dma resources from DT.
*
* Returns 0.
*/
static int _od_fill_dma_resources(struct omap_device *od,
struct resource *res)
{
int i, r;
for (i = 0; i < od->hwmods_cnt; i++) {
r = omap_hwmod_fill_dma_resources(od->hwmods[i], res);
res += r;
}
return 0;
}
/**
* 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;
struct resource *res = NULL;
int i, res_count;
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;
/*
* Non-DT Boot:
* Here, pdev->num_resources = 0, and we should get all the
* resources from hwmod.
*
* DT Boot:
* OF framework will construct the resource structure (currently
* does for MEM & IRQ resource) and we should respect/use these
* resources, killing hwmod dependency.
* If pdev->num_resources > 0, we assume that MEM & IRQ resources
* have been allocated by OF layer already (through DTB).
* As preparation for the future we examine the OF provided resources
* to see if we have DMA resources provided already. In this case
* there is no need to update the resources for the device, we use the
* OF provided ones.
*
* TODO: Once DMA resource is available from OF layer, we should
* kill filling any resources from hwmod.
*/
if (!pdev->num_resources) {
/* Count all resources for the device */
res_count = omap_device_count_resources(od, IORESOURCE_IRQ |
IORESOURCE_DMA |
IORESOURCE_MEM);
} else {
/* Take a look if we already have DMA resource via DT */
for (i = 0; i < pdev->num_resources; i++) {
struct resource *r = &pdev->resource[i];
/* We have it, no need to touch the resources */
if (r->flags == IORESOURCE_DMA)
goto have_everything;
}
/* Count only DMA resources for the device */
res_count = omap_device_count_resources(od, IORESOURCE_DMA);
/* The device has no DMA resource, no need for update */
if (!res_count)
goto have_everything;
res_count += pdev->num_resources;
}
/* Allocate resources memory to account for new resources */
res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
if (!res)
goto oda_exit3;
if (!pdev->num_resources) {
dev_dbg(&pdev->dev, "%s: using %d resources from hwmod\n",
__func__, res_count);
omap_device_fill_resources(od, res);
} else {
dev_dbg(&pdev->dev,
"%s: appending %d DMA resources from hwmod\n",
__func__, res_count - pdev->num_resources);
memcpy(res, pdev->resource,
sizeof(struct resource) * pdev->num_resources);
_od_fill_dma_resources(od, &res[pdev->num_resources]);
}
ret = platform_device_add_resources(pdev, res, res_count);
kfree(res);
if (ret)
goto oda_exit3;
have_everything:
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_exit3:
kfree(hwmods);
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_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)
{
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);
}
/**
* 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
*
* 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 platform_device __init *omap_device_build_ss(const char *pdev_name,
int pdev_id,
struct omap_hwmod **ohs,
int oh_cnt, void *pdata,
int pdata_len)
{
int ret = -ENOMEM;
struct platform_device *pdev;
struct omap_device *od;
if (!ohs || oh_cnt == 0 || !pdev_name)
return ERR_PTR(-EINVAL);
if (!pdata && pdata_len > 0)
return ERR_PTR(-EINVAL);
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);
od = omap_device_alloc(pdev, ohs, oh_cnt);
if (IS_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_RUNTIME
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)
omap_device_idle(pdev);
return ret;
}
static int _od_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
omap_device_enable(pdev);
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) {
ARM: OMAP2+: omap_device: maintain sane runtime pm status around suspend/resume OMAP device hooks around suspend|resume_noirq ensures that hwmod devices are forced to idle using omap_device_idle/enable as part of the last stage of suspend activity. For a device such as i2c who uses autosuspend, it is possible to enter the suspend path with dev->power.runtime_status = RPM_ACTIVE. As part of the suspend flow, the generic runtime logic would increment it's dev->power.disable_depth to 1. This should prevent further pm_runtime_get_sync from succeeding once the runtime_status has been set to RPM_SUSPENDED. Now, as part of the suspend_noirq handler in omap_device, we force the following: if the device status is !suspended, we force the device to idle using omap_device_idle (clocks are cut etc..). This ensures that from a hardware perspective, the device is "suspended". However, runtime_status is left to be active. *if* an operation is attempted after this point to pm_runtime_get_sync, runtime framework depends on runtime_status to indicate accurately the device status, and since it sees it to be ACTIVE, it assumes the module is functional and returns a non-error value. As a result the user will see pm_runtime_get succeed, however a register access will crash due to the lack of clocks. To prevent this from happening, we should ensure that runtime_status exactly indicates the device status. As a result of this change any further calls to pm_runtime_get* would return -EACCES (since disable_depth is 1). On resume, we restore the clocks and runtime status exactly as we suspended with. These operations are not expected to fail as we update the states after the core runtime framework has suspended itself and restore before the core runtime framework has resumed. Cc: stable@vger.kernel.org # v3.4+ Reported-by: J Keerthy <j-keerthy@ti.com> Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: Rajendra Nayak <rnayak@ti.com> Acked-by: Kevin Hilman <khilman@linaro.org> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2013-11-15 01:05:16 +08:00
pm_runtime_set_suspended(dev);
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);
ARM: OMAP2+: omap_device: maintain sane runtime pm status around suspend/resume OMAP device hooks around suspend|resume_noirq ensures that hwmod devices are forced to idle using omap_device_idle/enable as part of the last stage of suspend activity. For a device such as i2c who uses autosuspend, it is possible to enter the suspend path with dev->power.runtime_status = RPM_ACTIVE. As part of the suspend flow, the generic runtime logic would increment it's dev->power.disable_depth to 1. This should prevent further pm_runtime_get_sync from succeeding once the runtime_status has been set to RPM_SUSPENDED. Now, as part of the suspend_noirq handler in omap_device, we force the following: if the device status is !suspended, we force the device to idle using omap_device_idle (clocks are cut etc..). This ensures that from a hardware perspective, the device is "suspended". However, runtime_status is left to be active. *if* an operation is attempted after this point to pm_runtime_get_sync, runtime framework depends on runtime_status to indicate accurately the device status, and since it sees it to be ACTIVE, it assumes the module is functional and returns a non-error value. As a result the user will see pm_runtime_get succeed, however a register access will crash due to the lack of clocks. To prevent this from happening, we should ensure that runtime_status exactly indicates the device status. As a result of this change any further calls to pm_runtime_get* would return -EACCES (since disable_depth is 1). On resume, we restore the clocks and runtime status exactly as we suspended with. These operations are not expected to fail as we update the states after the core runtime framework has suspended itself and restore before the core runtime framework has resumed. Cc: stable@vger.kernel.org # v3.4+ Reported-by: J Keerthy <j-keerthy@ti.com> Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: Rajendra Nayak <rnayak@ti.com> Acked-by: Kevin Hilman <khilman@linaro.org> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2013-11-15 01:05:16 +08:00
if (od->flags & OMAP_DEVICE_SUSPENDED) {
od->flags &= ~OMAP_DEVICE_SUSPENDED;
omap_device_enable(pdev);
ARM: OMAP2+: omap_device: maintain sane runtime pm status around suspend/resume OMAP device hooks around suspend|resume_noirq ensures that hwmod devices are forced to idle using omap_device_idle/enable as part of the last stage of suspend activity. For a device such as i2c who uses autosuspend, it is possible to enter the suspend path with dev->power.runtime_status = RPM_ACTIVE. As part of the suspend flow, the generic runtime logic would increment it's dev->power.disable_depth to 1. This should prevent further pm_runtime_get_sync from succeeding once the runtime_status has been set to RPM_SUSPENDED. Now, as part of the suspend_noirq handler in omap_device, we force the following: if the device status is !suspended, we force the device to idle using omap_device_idle (clocks are cut etc..). This ensures that from a hardware perspective, the device is "suspended". However, runtime_status is left to be active. *if* an operation is attempted after this point to pm_runtime_get_sync, runtime framework depends on runtime_status to indicate accurately the device status, and since it sees it to be ACTIVE, it assumes the module is functional and returns a non-error value. As a result the user will see pm_runtime_get succeed, however a register access will crash due to the lack of clocks. To prevent this from happening, we should ensure that runtime_status exactly indicates the device status. As a result of this change any further calls to pm_runtime_get* would return -EACCES (since disable_depth is 1). On resume, we restore the clocks and runtime status exactly as we suspended with. These operations are not expected to fail as we update the states after the core runtime framework has suspended itself and restore before the core runtime framework has resumed. Cc: stable@vger.kernel.org # v3.4+ Reported-by: J Keerthy <j-keerthy@ti.com> Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: Rajendra Nayak <rnayak@ti.com> Acked-by: Kevin Hilman <khilman@linaro.org> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2013-11-15 01:05:16 +08:00
/*
* XXX: we run before core runtime pm has resumed itself. At
* this point in time, we just restore the runtime pm state and
* considering symmetric operations in resume, we donot expect
* to fail. If we failed, something changed in core runtime_pm
* framework OR some device driver messed things up, hence, WARN
*/
WARN(pm_runtime_set_active(dev),
"Could not set %s runtime state active\n", dev_name(dev));
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
.suspend_noirq = _od_suspend_noirq,
.resume_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);
pdev->dev.pm_domain = &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);
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);
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_core_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) {
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);