linux/drivers/regulator/virtual.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* reg-virtual-consumer.c
*
* Copyright 2008 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*/
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.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/module.h>
#include <linux/of.h>
struct virtual_consumer_data {
struct mutex lock;
struct regulator *regulator;
bool enabled;
int min_uV;
int max_uV;
int min_uA;
int max_uA;
unsigned int mode;
};
static void update_voltage_constraints(struct device *dev,
struct virtual_consumer_data *data)
{
int ret;
if (data->min_uV && data->max_uV
&& data->min_uV <= data->max_uV) {
dev_dbg(dev, "Requesting %d-%duV\n",
data->min_uV, data->max_uV);
ret = regulator_set_voltage(data->regulator,
data->min_uV, data->max_uV);
if (ret != 0) {
dev_err(dev,
"regulator_set_voltage() failed: %d\n", ret);
return;
}
}
if (data->min_uV && data->max_uV && !data->enabled) {
dev_dbg(dev, "Enabling regulator\n");
ret = regulator_enable(data->regulator);
if (ret == 0)
data->enabled = true;
else
dev_err(dev, "regulator_enable() failed: %d\n",
ret);
}
if (!(data->min_uV && data->max_uV) && data->enabled) {
dev_dbg(dev, "Disabling regulator\n");
ret = regulator_disable(data->regulator);
if (ret == 0)
data->enabled = false;
else
dev_err(dev, "regulator_disable() failed: %d\n",
ret);
}
}
static void update_current_limit_constraints(struct device *dev,
struct virtual_consumer_data *data)
{
int ret;
if (data->max_uA
&& data->min_uA <= data->max_uA) {
dev_dbg(dev, "Requesting %d-%duA\n",
data->min_uA, data->max_uA);
ret = regulator_set_current_limit(data->regulator,
data->min_uA, data->max_uA);
if (ret != 0) {
dev_err(dev,
"regulator_set_current_limit() failed: %d\n",
ret);
return;
}
}
if (data->max_uA && !data->enabled) {
dev_dbg(dev, "Enabling regulator\n");
ret = regulator_enable(data->regulator);
if (ret == 0)
data->enabled = true;
else
dev_err(dev, "regulator_enable() failed: %d\n",
ret);
}
if (!(data->min_uA && data->max_uA) && data->enabled) {
dev_dbg(dev, "Disabling regulator\n");
ret = regulator_disable(data->regulator);
if (ret == 0)
data->enabled = false;
else
dev_err(dev, "regulator_disable() failed: %d\n",
ret);
}
}
static ssize_t show_min_uV(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", data->min_uV);
}
static ssize_t set_min_uV(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
long val;
if (kstrtol(buf, 10, &val) != 0)
return count;
mutex_lock(&data->lock);
data->min_uV = val;
update_voltage_constraints(dev, data);
mutex_unlock(&data->lock);
return count;
}
static ssize_t show_max_uV(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", data->max_uV);
}
static ssize_t set_max_uV(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
long val;
if (kstrtol(buf, 10, &val) != 0)
return count;
mutex_lock(&data->lock);
data->max_uV = val;
update_voltage_constraints(dev, data);
mutex_unlock(&data->lock);
return count;
}
static ssize_t show_min_uA(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", data->min_uA);
}
static ssize_t set_min_uA(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
long val;
if (kstrtol(buf, 10, &val) != 0)
return count;
mutex_lock(&data->lock);
data->min_uA = val;
update_current_limit_constraints(dev, data);
mutex_unlock(&data->lock);
return count;
}
static ssize_t show_max_uA(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", data->max_uA);
}
static ssize_t set_max_uA(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
long val;
if (kstrtol(buf, 10, &val) != 0)
return count;
mutex_lock(&data->lock);
data->max_uA = val;
update_current_limit_constraints(dev, data);
mutex_unlock(&data->lock);
return count;
}
static ssize_t show_mode(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
switch (data->mode) {
case REGULATOR_MODE_FAST:
return sprintf(buf, "fast\n");
case REGULATOR_MODE_NORMAL:
return sprintf(buf, "normal\n");
case REGULATOR_MODE_IDLE:
return sprintf(buf, "idle\n");
case REGULATOR_MODE_STANDBY:
return sprintf(buf, "standby\n");
default:
return sprintf(buf, "unknown\n");
}
}
static ssize_t set_mode(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct virtual_consumer_data *data = dev_get_drvdata(dev);
unsigned int mode;
int ret;
regulator: minor cleanup of virtual consumer On Thu, 15 Jan 2009 16:10:22 -0800 Andrew Morton <akpm@linux-foundation.org> wrote: > On Wed, 14 Jan 2009 13:16:27 -0800 > David Brownell <david-b@pacbell.net> wrote: > > > From: David Brownell <dbrownell@users.sourceforge.net> > > > > Minor cleanup to the regulator set_mode sysfs support: > > switch to sysfs_streq() in set_mode(), which is also > > a code shrink. Use the same strings that get_mode() > > uses, shrinking data too. > > > > Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> > > --- > > drivers/regulator/virtual.c | 8 ++++---- > > 1 file changed, 4 insertions(+), 4 deletions(-) > > > > --- a/drivers/regulator/virtual.c > > +++ b/drivers/regulator/virtual.c > > @@ -226,13 +226,13 @@ static ssize_t set_mode(struct device *d > > unsigned int mode; > > int ret; > > > > - if (strncmp(buf, "fast", strlen("fast")) == 0) > > + if (sysfs_streq(buf, "fast\n") == 0) > > mode = REGULATOR_MODE_FAST; > > - else if (strncmp(buf, "normal", strlen("normal")) == 0) > > + else if (sysfs_streq(buf, "normal\n") == 0) > > mode = REGULATOR_MODE_NORMAL; > > - else if (strncmp(buf, "idle", strlen("idle")) == 0) > > + else if (sysfs_streq(buf, "idle\n") == 0) > > mode = REGULATOR_MODE_IDLE; > > - else if (strncmp(buf, "standby", strlen("standby")) == 0) > > + else if (sysfs_streq(buf, "standby\n") == 0) > > mode = REGULATOR_MODE_STANDBY; > > we don't need the \n's, do we? oh, it's for the string sharing. Sneaky. I wonder how many people will try to fix that up for us? Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-01-16 08:13:01 +08:00
/*
* sysfs_streq() doesn't need the \n's, but we add them so the strings
* will be shared with show_mode(), above.
*/
if (sysfs_streq(buf, "fast\n"))
mode = REGULATOR_MODE_FAST;
else if (sysfs_streq(buf, "normal\n"))
mode = REGULATOR_MODE_NORMAL;
else if (sysfs_streq(buf, "idle\n"))
mode = REGULATOR_MODE_IDLE;
else if (sysfs_streq(buf, "standby\n"))
mode = REGULATOR_MODE_STANDBY;
else {
dev_err(dev, "Configuring invalid mode\n");
return count;
}
mutex_lock(&data->lock);
ret = regulator_set_mode(data->regulator, mode);
if (ret == 0)
data->mode = mode;
else
dev_err(dev, "Failed to configure mode: %d\n", ret);
mutex_unlock(&data->lock);
return count;
}
static DEVICE_ATTR(min_microvolts, 0664, show_min_uV, set_min_uV);
static DEVICE_ATTR(max_microvolts, 0664, show_max_uV, set_max_uV);
static DEVICE_ATTR(min_microamps, 0664, show_min_uA, set_min_uA);
static DEVICE_ATTR(max_microamps, 0664, show_max_uA, set_max_uA);
static DEVICE_ATTR(mode, 0664, show_mode, set_mode);
static struct attribute *regulator_virtual_attributes[] = {
&dev_attr_min_microvolts.attr,
&dev_attr_max_microvolts.attr,
&dev_attr_min_microamps.attr,
&dev_attr_max_microamps.attr,
&dev_attr_mode.attr,
NULL
};
static const struct attribute_group regulator_virtual_attr_group = {
.attrs = regulator_virtual_attributes,
};
#ifdef CONFIG_OF
static const struct of_device_id regulator_virtual_consumer_of_match[] = {
{ .compatible = "regulator-virtual-consumer" },
{},
};
MODULE_DEVICE_TABLE(of, regulator_virtual_consumer_of_match);
#endif
static int regulator_virtual_probe(struct platform_device *pdev)
{
char *reg_id = dev_get_platdata(&pdev->dev);
struct virtual_consumer_data *drvdata;
static bool warned;
int ret;
if (!warned) {
warned = true;
pr_warn("**********************************************************\n");
pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
pr_warn("** **\n");
pr_warn("** regulator-virtual-consumer is only for testing and **\n");
pr_warn("** debugging. Do not use it in a production kernel. **\n");
pr_warn("** **\n");
pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
pr_warn("**********************************************************\n");
}
drvdata = devm_kzalloc(&pdev->dev, sizeof(struct virtual_consumer_data),
GFP_KERNEL);
if (drvdata == NULL)
return -ENOMEM;
/*
* This virtual consumer does not have any hardware-defined supply
* name, so just allow the regulator to be specified in a property
* named "default-supply" when we're being probed from devicetree.
*/
if (!reg_id && pdev->dev.of_node)
reg_id = "default";
mutex_init(&drvdata->lock);
drvdata->regulator = devm_regulator_get(&pdev->dev, reg_id);
if (IS_ERR(drvdata->regulator))
return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->regulator),
"Failed to obtain supply '%s'\n",
reg_id);
ret = sysfs_create_group(&pdev->dev.kobj,
&regulator_virtual_attr_group);
if (ret != 0) {
dev_err(&pdev->dev,
"Failed to create attribute group: %d\n", ret);
return ret;
}
drvdata->mode = regulator_get_mode(drvdata->regulator);
platform_set_drvdata(pdev, drvdata);
return 0;
}
static void regulator_virtual_remove(struct platform_device *pdev)
{
struct virtual_consumer_data *drvdata = platform_get_drvdata(pdev);
sysfs_remove_group(&pdev->dev.kobj, &regulator_virtual_attr_group);
if (drvdata->enabled)
regulator_disable(drvdata->regulator);
}
static struct platform_driver regulator_virtual_consumer_driver = {
.probe = regulator_virtual_probe,
.remove_new = regulator_virtual_remove,
.driver = {
.name = "reg-virt-consumer",
regulator: Set PROBE_PREFER_ASYNCHRONOUS for drivers that existed in 4.14 Probing of regulators can be a slow operation and can contribute to slower boot times. This is especially true if a regulator is turned on at probe time (with regulator-boot-on or regulator-always-on) and the regulator requires delays (off-on-time, ramp time, etc). While the overall kernel is not ready to switch to async probe by default, as per the discussion on the mailing lists [1] it is believed that the regulator subsystem is in good shape and we can move regulator drivers over wholesale. There is no way to just magically opt in all regulators (regulators are just normal drivers like platform_driver), so we set PROBE_PREFER_ASYNCHRONOUS for all regulators found in 'drivers/regulator' individually. Given the number of drivers touched and the impossibility to test this ahead of time, it wouldn't be shocking at all if this caused a regression for someone. If there is a regression caused by this patch, it's likely to be one of the cases talked about in [1]. As a "quick fix", drivers involved in the regression could be fixed by changing them to PROBE_FORCE_SYNCHRONOUS. That being said, the correct fix would be to directly fix the problem that caused the issue with async probe. The approach here follows a similar approach that was used for the mmc subsystem several years ago [2]. In fact, I ran nearly the same python script to auto-generate the changes. The only thing I changed was to search for "i2c_driver", "spmi_driver", and "spi_driver" in addition to "platform_driver". [1] https://lore.kernel.org/r/06db017f-e985-4434-8d1d-02ca2100cca0@sirena.org.uk [2] https://lore.kernel.org/r/20200903232441.2694866-1-dianders@chromium.org/ Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20230316125351.1.I2a4677392a38db5758dee0788b2cea5872562a82@changeid Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-17 03:54:38 +08:00
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.of_match_table = of_match_ptr(regulator_virtual_consumer_of_match),
},
};
module_platform_driver(regulator_virtual_consumer_driver);
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("Virtual regulator consumer");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:reg-virt-consumer");