linux/arch/arm/plat-samsung/adc.c

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/* arch/arm/plat-samsung/adc.c
*
* Copyright (c) 2008 Simtec Electronics
* http://armlinux.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
*
* Samsung ADC 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/sched.h>
#include <linux/list.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 09:04:11 +01:00
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <plat/regs-adc.h>
#include <plat/adc.h>
/* This driver is designed to control the usage of the ADC block between
* the touchscreen and any other drivers that may need to use it, such as
* the hwmon driver.
*
* Priority will be given to the touchscreen driver, but as this itself is
* rate limited it should not starve other requests which are processed in
* order that they are received.
*
* Each user registers to get a client block which uniquely identifies it
* and stores information such as the necessary functions to callback when
* action is required.
*/
enum s3c_cpu_type {
TYPE_S3C24XX,
TYPE_S3C64XX
};
struct s3c_adc_client {
struct platform_device *pdev;
struct list_head pend;
wait_queue_head_t *wait;
unsigned int nr_samples;
int result;
unsigned char is_ts;
unsigned char channel;
void (*select_cb)(struct s3c_adc_client *c, unsigned selected);
void (*convert_cb)(struct s3c_adc_client *c,
unsigned val1, unsigned val2,
unsigned *samples_left);
};
struct adc_device {
struct platform_device *pdev;
struct platform_device *owner;
struct clk *clk;
struct s3c_adc_client *cur;
struct s3c_adc_client *ts_pend;
void __iomem *regs;
unsigned int prescale;
int irq;
};
static struct adc_device *adc_dev;
static LIST_HEAD(adc_pending);
#define adc_dbg(_adc, msg...) dev_dbg(&(_adc)->pdev->dev, msg)
static inline void s3c_adc_convert(struct adc_device *adc)
{
unsigned con = readl(adc->regs + S3C2410_ADCCON);
con |= S3C2410_ADCCON_ENABLE_START;
writel(con, adc->regs + S3C2410_ADCCON);
}
static inline void s3c_adc_select(struct adc_device *adc,
struct s3c_adc_client *client)
{
unsigned con = readl(adc->regs + S3C2410_ADCCON);
client->select_cb(client, 1);
con &= ~S3C2410_ADCCON_MUXMASK;
con &= ~S3C2410_ADCCON_STDBM;
con &= ~S3C2410_ADCCON_STARTMASK;
if (!client->is_ts)
con |= S3C2410_ADCCON_SELMUX(client->channel);
writel(con, adc->regs + S3C2410_ADCCON);
}
static void s3c_adc_dbgshow(struct adc_device *adc)
{
adc_dbg(adc, "CON=%08x, TSC=%08x, DLY=%08x\n",
readl(adc->regs + S3C2410_ADCCON),
readl(adc->regs + S3C2410_ADCTSC),
readl(adc->regs + S3C2410_ADCDLY));
}
static void s3c_adc_try(struct adc_device *adc)
{
struct s3c_adc_client *next = adc->ts_pend;
if (!next && !list_empty(&adc_pending)) {
next = list_first_entry(&adc_pending,
struct s3c_adc_client, pend);
list_del(&next->pend);
} else
adc->ts_pend = NULL;
if (next) {
adc_dbg(adc, "new client is %p\n", next);
adc->cur = next;
s3c_adc_select(adc, next);
s3c_adc_convert(adc);
s3c_adc_dbgshow(adc);
}
}
int s3c_adc_start(struct s3c_adc_client *client,
unsigned int channel, unsigned int nr_samples)
{
struct adc_device *adc = adc_dev;
unsigned long flags;
if (!adc) {
printk(KERN_ERR "%s: failed to find adc\n", __func__);
return -EINVAL;
}
if (client->is_ts && adc->ts_pend)
return -EAGAIN;
local_irq_save(flags);
client->channel = channel;
client->nr_samples = nr_samples;
if (client->is_ts)
adc->ts_pend = client;
else
list_add_tail(&client->pend, &adc_pending);
if (!adc->cur)
s3c_adc_try(adc);
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL_GPL(s3c_adc_start);
static void s3c_convert_done(struct s3c_adc_client *client,
unsigned v, unsigned u, unsigned *left)
{
client->result = v;
wake_up(client->wait);
}
int s3c_adc_read(struct s3c_adc_client *client, unsigned int ch)
{
DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
int ret;
client->convert_cb = s3c_convert_done;
client->wait = &wake;
client->result = -1;
ret = s3c_adc_start(client, ch, 1);
if (ret < 0)
goto err;
ret = wait_event_timeout(wake, client->result >= 0, HZ / 2);
if (client->result < 0) {
ret = -ETIMEDOUT;
goto err;
}
client->convert_cb = NULL;
return client->result;
err:
return ret;
}
EXPORT_SYMBOL_GPL(s3c_adc_read);
static void s3c_adc_default_select(struct s3c_adc_client *client,
unsigned select)
{
}
struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev,
void (*select)(struct s3c_adc_client *client,
unsigned int selected),
void (*conv)(struct s3c_adc_client *client,
unsigned d0, unsigned d1,
unsigned *samples_left),
unsigned int is_ts)
{
struct s3c_adc_client *client;
WARN_ON(!pdev);
if (!select)
select = s3c_adc_default_select;
if (!pdev)
return ERR_PTR(-EINVAL);
client = kzalloc(sizeof(struct s3c_adc_client), GFP_KERNEL);
if (!client) {
dev_err(&pdev->dev, "no memory for adc client\n");
return ERR_PTR(-ENOMEM);
}
client->pdev = pdev;
client->is_ts = is_ts;
client->select_cb = select;
client->convert_cb = conv;
return client;
}
EXPORT_SYMBOL_GPL(s3c_adc_register);
void s3c_adc_release(struct s3c_adc_client *client)
{
/* We should really check that nothing is in progress. */
if (adc_dev->cur == client)
adc_dev->cur = NULL;
if (adc_dev->ts_pend == client)
adc_dev->ts_pend = NULL;
else {
struct list_head *p, *n;
struct s3c_adc_client *tmp;
list_for_each_safe(p, n, &adc_pending) {
tmp = list_entry(p, struct s3c_adc_client, pend);
if (tmp == client)
list_del(&tmp->pend);
}
}
if (adc_dev->cur == NULL)
s3c_adc_try(adc_dev);
kfree(client);
}
EXPORT_SYMBOL_GPL(s3c_adc_release);
static irqreturn_t s3c_adc_irq(int irq, void *pw)
{
struct adc_device *adc = pw;
struct s3c_adc_client *client = adc->cur;
enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data;
unsigned long flags;
unsigned data0, data1;
if (!client) {
dev_warn(&adc->pdev->dev, "%s: no adc pending\n", __func__);
goto exit;
}
data0 = readl(adc->regs + S3C2410_ADCDAT0);
data1 = readl(adc->regs + S3C2410_ADCDAT1);
adc_dbg(adc, "read %d: 0x%04x, 0x%04x\n", client->nr_samples, data0, data1);
client->nr_samples--;
if (cpu == TYPE_S3C64XX) {
/* S3C64XX ADC resolution is 12-bit */
data0 &= 0xfff;
data1 &= 0xfff;
} else {
data0 &= 0x3ff;
data1 &= 0x3ff;
}
if (client->convert_cb)
(client->convert_cb)(client, data0, data1, &client->nr_samples);
if (client->nr_samples > 0) {
/* fire another conversion for this */
client->select_cb(client, 1);
s3c_adc_convert(adc);
} else {
local_irq_save(flags);
(client->select_cb)(client, 0);
adc->cur = NULL;
s3c_adc_try(adc);
local_irq_restore(flags);
}
exit:
if (cpu == TYPE_S3C64XX) {
/* Clear ADC interrupt */
writel(0, adc->regs + S3C64XX_ADCCLRINT);
}
return IRQ_HANDLED;
}
static int s3c_adc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct adc_device *adc;
struct resource *regs;
int ret;
unsigned tmp;
adc = kzalloc(sizeof(struct adc_device), GFP_KERNEL);
if (adc == NULL) {
dev_err(dev, "failed to allocate adc_device\n");
return -ENOMEM;
}
adc->pdev = pdev;
adc->prescale = S3C2410_ADCCON_PRSCVL(49);
adc->irq = platform_get_irq(pdev, 1);
if (adc->irq <= 0) {
dev_err(dev, "failed to get adc irq\n");
ret = -ENOENT;
goto err_alloc;
}
ret = request_irq(adc->irq, s3c_adc_irq, 0, dev_name(dev), adc);
if (ret < 0) {
dev_err(dev, "failed to attach adc irq\n");
goto err_alloc;
}
adc->clk = clk_get(dev, "adc");
if (IS_ERR(adc->clk)) {
dev_err(dev, "failed to get adc clock\n");
ret = PTR_ERR(adc->clk);
goto err_irq;
}
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs) {
dev_err(dev, "failed to find registers\n");
ret = -ENXIO;
goto err_clk;
}
adc->regs = ioremap(regs->start, resource_size(regs));
if (!adc->regs) {
dev_err(dev, "failed to map registers\n");
ret = -ENXIO;
goto err_clk;
}
clk_enable(adc->clk);
tmp = adc->prescale | S3C2410_ADCCON_PRSCEN;
if (platform_get_device_id(pdev)->driver_data == TYPE_S3C64XX) {
/* Enable 12-bit ADC resolution */
tmp |= S3C64XX_ADCCON_RESSEL;
}
writel(tmp, adc->regs + S3C2410_ADCCON);
dev_info(dev, "attached adc driver\n");
platform_set_drvdata(pdev, adc);
adc_dev = adc;
return 0;
err_clk:
clk_put(adc->clk);
err_irq:
free_irq(adc->irq, adc);
err_alloc:
kfree(adc);
return ret;
}
static int __devexit s3c_adc_remove(struct platform_device *pdev)
{
struct adc_device *adc = platform_get_drvdata(pdev);
iounmap(adc->regs);
free_irq(adc->irq, adc);
clk_disable(adc->clk);
clk_put(adc->clk);
kfree(adc);
return 0;
}
#ifdef CONFIG_PM
static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state)
{
struct adc_device *adc = platform_get_drvdata(pdev);
u32 con;
con = readl(adc->regs + S3C2410_ADCCON);
con |= S3C2410_ADCCON_STDBM;
writel(con, adc->regs + S3C2410_ADCCON);
disable_irq(adc->irq);
clk_disable(adc->clk);
return 0;
}
static int s3c_adc_resume(struct platform_device *pdev)
{
struct adc_device *adc = platform_get_drvdata(pdev);
clk_enable(adc->clk);
enable_irq(adc->irq);
writel(adc->prescale | S3C2410_ADCCON_PRSCEN,
adc->regs + S3C2410_ADCCON);
return 0;
}
#else
#define s3c_adc_suspend NULL
#define s3c_adc_resume NULL
#endif
static struct platform_device_id s3c_adc_driver_ids[] = {
{
.name = "s3c24xx-adc",
.driver_data = TYPE_S3C24XX,
}, {
.name = "s3c64xx-adc",
.driver_data = TYPE_S3C64XX,
},
{ }
};
MODULE_DEVICE_TABLE(platform, s3c_adc_driver_ids);
static struct platform_driver s3c_adc_driver = {
.id_table = s3c_adc_driver_ids,
.driver = {
.name = "s3c-adc",
.owner = THIS_MODULE,
},
.probe = s3c_adc_probe,
.remove = __devexit_p(s3c_adc_remove),
.suspend = s3c_adc_suspend,
.resume = s3c_adc_resume,
};
static int __init adc_init(void)
{
int ret;
ret = platform_driver_register(&s3c_adc_driver);
if (ret)
printk(KERN_ERR "%s: failed to add adc driver\n", __func__);
return ret;
}
arch_initcall(adc_init);