linux/arch/arm/plat-samsung/pwm.c
Tejun Heo 5a0e3ad6af 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>
2010-03-30 22:02:32 +09:00

447 lines
9.4 KiB
C

/* arch/arm/plat-s3c/pwm.c
*
* Copyright (c) 2007 Ben Dooks
* Copyright (c) 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
*
* S3C series PWM device core
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/pwm.h>
#include <mach/irqs.h>
#include <mach/map.h>
#include <plat/devs.h>
#include <plat/regs-timer.h>
struct pwm_device {
struct list_head list;
struct platform_device *pdev;
struct clk *clk_div;
struct clk *clk;
const char *label;
unsigned int period_ns;
unsigned int duty_ns;
unsigned char tcon_base;
unsigned char running;
unsigned char use_count;
unsigned char pwm_id;
};
#define pwm_dbg(_pwm, msg...) dev_dbg(&(_pwm)->pdev->dev, msg)
static struct clk *clk_scaler[2];
/* Standard setup for a timer block. */
#define TIMER_RESOURCE_SIZE (1)
#define TIMER_RESOURCE(_tmr, _irq) \
(struct resource [TIMER_RESOURCE_SIZE]) { \
[0] = { \
.start = _irq, \
.end = _irq, \
.flags = IORESOURCE_IRQ \
} \
}
#define DEFINE_S3C_TIMER(_tmr_no, _irq) \
.name = "s3c24xx-pwm", \
.id = _tmr_no, \
.num_resources = TIMER_RESOURCE_SIZE, \
.resource = TIMER_RESOURCE(_tmr_no, _irq), \
/* since we already have an static mapping for the timer, we do not
* bother setting any IO resource for the base.
*/
struct platform_device s3c_device_timer[] = {
[0] = { DEFINE_S3C_TIMER(0, IRQ_TIMER0) },
[1] = { DEFINE_S3C_TIMER(1, IRQ_TIMER1) },
[2] = { DEFINE_S3C_TIMER(2, IRQ_TIMER2) },
[3] = { DEFINE_S3C_TIMER(3, IRQ_TIMER3) },
[4] = { DEFINE_S3C_TIMER(4, IRQ_TIMER4) },
};
static inline int pwm_is_tdiv(struct pwm_device *pwm)
{
return clk_get_parent(pwm->clk) == pwm->clk_div;
}
static DEFINE_MUTEX(pwm_lock);
static LIST_HEAD(pwm_list);
struct pwm_device *pwm_request(int pwm_id, const char *label)
{
struct pwm_device *pwm;
int found = 0;
mutex_lock(&pwm_lock);
list_for_each_entry(pwm, &pwm_list, list) {
if (pwm->pwm_id == pwm_id) {
found = 1;
break;
}
}
if (found) {
if (pwm->use_count == 0) {
pwm->use_count = 1;
pwm->label = label;
} else
pwm = ERR_PTR(-EBUSY);
} else
pwm = ERR_PTR(-ENOENT);
mutex_unlock(&pwm_lock);
return pwm;
}
EXPORT_SYMBOL(pwm_request);
void pwm_free(struct pwm_device *pwm)
{
mutex_lock(&pwm_lock);
if (pwm->use_count) {
pwm->use_count--;
pwm->label = NULL;
} else
printk(KERN_ERR "PWM%d device already freed\n", pwm->pwm_id);
mutex_unlock(&pwm_lock);
}
EXPORT_SYMBOL(pwm_free);
#define pwm_tcon_start(pwm) (1 << (pwm->tcon_base + 0))
#define pwm_tcon_invert(pwm) (1 << (pwm->tcon_base + 2))
#define pwm_tcon_autoreload(pwm) (1 << (pwm->tcon_base + 3))
#define pwm_tcon_manulupdate(pwm) (1 << (pwm->tcon_base + 1))
int pwm_enable(struct pwm_device *pwm)
{
unsigned long flags;
unsigned long tcon;
local_irq_save(flags);
tcon = __raw_readl(S3C2410_TCON);
tcon |= pwm_tcon_start(pwm);
__raw_writel(tcon, S3C2410_TCON);
local_irq_restore(flags);
pwm->running = 1;
return 0;
}
EXPORT_SYMBOL(pwm_enable);
void pwm_disable(struct pwm_device *pwm)
{
unsigned long flags;
unsigned long tcon;
local_irq_save(flags);
tcon = __raw_readl(S3C2410_TCON);
tcon &= ~pwm_tcon_start(pwm);
__raw_writel(tcon, S3C2410_TCON);
local_irq_restore(flags);
pwm->running = 0;
}
EXPORT_SYMBOL(pwm_disable);
static unsigned long pwm_calc_tin(struct pwm_device *pwm, unsigned long freq)
{
unsigned long tin_parent_rate;
unsigned int div;
tin_parent_rate = clk_get_rate(clk_get_parent(pwm->clk_div));
pwm_dbg(pwm, "tin parent at %lu\n", tin_parent_rate);
for (div = 2; div <= 16; div *= 2) {
if ((tin_parent_rate / (div << 16)) < freq)
return tin_parent_rate / div;
}
return tin_parent_rate / 16;
}
#define NS_IN_HZ (1000000000UL)
int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
{
unsigned long tin_rate;
unsigned long tin_ns;
unsigned long period;
unsigned long flags;
unsigned long tcon;
unsigned long tcnt;
long tcmp;
/* We currently avoid using 64bit arithmetic by using the
* fact that anything faster than 1Hz is easily representable
* by 32bits. */
if (period_ns > NS_IN_HZ || duty_ns > NS_IN_HZ)
return -ERANGE;
if (duty_ns > period_ns)
return -EINVAL;
if (period_ns == pwm->period_ns &&
duty_ns == pwm->duty_ns)
return 0;
/* The TCMP and TCNT can be read without a lock, they're not
* shared between the timers. */
tcmp = __raw_readl(S3C2410_TCMPB(pwm->pwm_id));
tcnt = __raw_readl(S3C2410_TCNTB(pwm->pwm_id));
period = NS_IN_HZ / period_ns;
pwm_dbg(pwm, "duty_ns=%d, period_ns=%d (%lu)\n",
duty_ns, period_ns, period);
/* Check to see if we are changing the clock rate of the PWM */
if (pwm->period_ns != period_ns) {
if (pwm_is_tdiv(pwm)) {
tin_rate = pwm_calc_tin(pwm, period);
clk_set_rate(pwm->clk_div, tin_rate);
} else
tin_rate = clk_get_rate(pwm->clk);
pwm->period_ns = period_ns;
pwm_dbg(pwm, "tin_rate=%lu\n", tin_rate);
tin_ns = NS_IN_HZ / tin_rate;
tcnt = period_ns / tin_ns;
} else
tin_ns = NS_IN_HZ / clk_get_rate(pwm->clk);
/* Note, counters count down */
tcmp = duty_ns / tin_ns;
tcmp = tcnt - tcmp;
/* the pwm hw only checks the compare register after a decrement,
so the pin never toggles if tcmp = tcnt */
if (tcmp == tcnt)
tcmp--;
pwm_dbg(pwm, "tin_ns=%lu, tcmp=%ld/%lu\n", tin_ns, tcmp, tcnt);
if (tcmp < 0)
tcmp = 0;
/* Update the PWM register block. */
local_irq_save(flags);
__raw_writel(tcmp, S3C2410_TCMPB(pwm->pwm_id));
__raw_writel(tcnt, S3C2410_TCNTB(pwm->pwm_id));
tcon = __raw_readl(S3C2410_TCON);
tcon |= pwm_tcon_manulupdate(pwm);
tcon |= pwm_tcon_autoreload(pwm);
__raw_writel(tcon, S3C2410_TCON);
tcon &= ~pwm_tcon_manulupdate(pwm);
__raw_writel(tcon, S3C2410_TCON);
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL(pwm_config);
static int pwm_register(struct pwm_device *pwm)
{
pwm->duty_ns = -1;
pwm->period_ns = -1;
mutex_lock(&pwm_lock);
list_add_tail(&pwm->list, &pwm_list);
mutex_unlock(&pwm_lock);
return 0;
}
static int s3c_pwm_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct pwm_device *pwm;
unsigned long flags;
unsigned long tcon;
unsigned int id = pdev->id;
int ret;
if (id == 4) {
dev_err(dev, "TIMER4 is currently not supported\n");
return -ENXIO;
}
pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
if (pwm == NULL) {
dev_err(dev, "failed to allocate pwm_device\n");
return -ENOMEM;
}
pwm->pdev = pdev;
pwm->pwm_id = id;
/* calculate base of control bits in TCON */
pwm->tcon_base = id == 0 ? 0 : (id * 4) + 4;
pwm->clk = clk_get(dev, "pwm-tin");
if (IS_ERR(pwm->clk)) {
dev_err(dev, "failed to get pwm tin clk\n");
ret = PTR_ERR(pwm->clk);
goto err_alloc;
}
pwm->clk_div = clk_get(dev, "pwm-tdiv");
if (IS_ERR(pwm->clk_div)) {
dev_err(dev, "failed to get pwm tdiv clk\n");
ret = PTR_ERR(pwm->clk_div);
goto err_clk_tin;
}
local_irq_save(flags);
tcon = __raw_readl(S3C2410_TCON);
tcon |= pwm_tcon_invert(pwm);
__raw_writel(tcon, S3C2410_TCON);
local_irq_restore(flags);
ret = pwm_register(pwm);
if (ret) {
dev_err(dev, "failed to register pwm\n");
goto err_clk_tdiv;
}
pwm_dbg(pwm, "config bits %02x\n",
(__raw_readl(S3C2410_TCON) >> pwm->tcon_base) & 0x0f);
dev_info(dev, "tin at %lu, tdiv at %lu, tin=%sclk, base %d\n",
clk_get_rate(pwm->clk),
clk_get_rate(pwm->clk_div),
pwm_is_tdiv(pwm) ? "div" : "ext", pwm->tcon_base);
platform_set_drvdata(pdev, pwm);
return 0;
err_clk_tdiv:
clk_put(pwm->clk_div);
err_clk_tin:
clk_put(pwm->clk);
err_alloc:
kfree(pwm);
return ret;
}
static int __devexit s3c_pwm_remove(struct platform_device *pdev)
{
struct pwm_device *pwm = platform_get_drvdata(pdev);
clk_put(pwm->clk_div);
clk_put(pwm->clk);
kfree(pwm);
return 0;
}
#ifdef CONFIG_PM
static int s3c_pwm_suspend(struct platform_device *pdev, pm_message_t state)
{
struct pwm_device *pwm = platform_get_drvdata(pdev);
/* No one preserve these values during suspend so reset them
* Otherwise driver leaves PWM unconfigured if same values
* passed to pwm_config
*/
pwm->period_ns = 0;
pwm->duty_ns = 0;
return 0;
}
static int s3c_pwm_resume(struct platform_device *pdev)
{
struct pwm_device *pwm = platform_get_drvdata(pdev);
unsigned long tcon;
/* Restore invertion */
tcon = __raw_readl(S3C2410_TCON);
tcon |= pwm_tcon_invert(pwm);
__raw_writel(tcon, S3C2410_TCON);
return 0;
}
#else
#define s3c_pwm_suspend NULL
#define s3c_pwm_resume NULL
#endif
static struct platform_driver s3c_pwm_driver = {
.driver = {
.name = "s3c24xx-pwm",
.owner = THIS_MODULE,
},
.probe = s3c_pwm_probe,
.remove = __devexit_p(s3c_pwm_remove),
.suspend = s3c_pwm_suspend,
.resume = s3c_pwm_resume,
};
static int __init pwm_init(void)
{
int ret;
clk_scaler[0] = clk_get(NULL, "pwm-scaler0");
clk_scaler[1] = clk_get(NULL, "pwm-scaler1");
if (IS_ERR(clk_scaler[0]) || IS_ERR(clk_scaler[1])) {
printk(KERN_ERR "%s: failed to get scaler clocks\n", __func__);
return -EINVAL;
}
ret = platform_driver_register(&s3c_pwm_driver);
if (ret)
printk(KERN_ERR "%s: failed to add pwm driver\n", __func__);
return ret;
}
arch_initcall(pwm_init);