linux/drivers/gpio/pca953x.c

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/*
* pca953x.c - 4/8/16 bit I/O ports
*
* Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
* Copyright (C) 2007 Marvell International Ltd.
*
* Derived from drivers/i2c/chips/pca9539.c
*
* 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; version 2 of the License.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/i2c.h>
#include <linux/i2c/pca953x.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 08:04:11 +00:00
#include <linux/slab.h>
#ifdef CONFIG_OF_GPIO
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
#endif
#define PCA953X_INPUT 0
#define PCA953X_OUTPUT 1
#define PCA953X_INVERT 2
#define PCA953X_DIRECTION 3
#define PCA953X_GPIOS 0x00FF
#define PCA953X_INT 0x0100
static const struct i2c_device_id pca953x_id[] = {
{ "pca9534", 8 | PCA953X_INT, },
{ "pca9535", 16 | PCA953X_INT, },
{ "pca9536", 4, },
{ "pca9537", 4 | PCA953X_INT, },
{ "pca9538", 8 | PCA953X_INT, },
{ "pca9539", 16 | PCA953X_INT, },
{ "pca9554", 8 | PCA953X_INT, },
{ "pca9555", 16 | PCA953X_INT, },
{ "pca9556", 8, },
{ "pca9557", 8, },
{ "max7310", 8, },
{ "max7312", 16 | PCA953X_INT, },
{ "max7313", 16 | PCA953X_INT, },
{ "max7315", 8 | PCA953X_INT, },
{ "pca6107", 8 | PCA953X_INT, },
{ "tca6408", 8 | PCA953X_INT, },
{ "tca6416", 16 | PCA953X_INT, },
/* NYET: { "tca6424", 24, }, */
{ }
};
MODULE_DEVICE_TABLE(i2c, pca953x_id);
struct pca953x_chip {
unsigned gpio_start;
uint16_t reg_output;
uint16_t reg_direction;
struct mutex i2c_lock;
#ifdef CONFIG_GPIO_PCA953X_IRQ
struct mutex irq_lock;
uint16_t irq_mask;
uint16_t irq_stat;
uint16_t irq_trig_raise;
uint16_t irq_trig_fall;
int irq_base;
#endif
struct i2c_client *client;
struct pca953x_platform_data *dyn_pdata;
struct gpio_chip gpio_chip;
const char *const *names;
};
static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
{
int ret;
if (chip->gpio_chip.ngpio <= 8)
ret = i2c_smbus_write_byte_data(chip->client, reg, val);
else
ret = i2c_smbus_write_word_data(chip->client, reg << 1, val);
if (ret < 0) {
dev_err(&chip->client->dev, "failed writing register\n");
return ret;
}
return 0;
}
static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val)
{
int ret;
if (chip->gpio_chip.ngpio <= 8)
ret = i2c_smbus_read_byte_data(chip->client, reg);
else
ret = i2c_smbus_read_word_data(chip->client, reg << 1);
if (ret < 0) {
dev_err(&chip->client->dev, "failed reading register\n");
return ret;
}
*val = (uint16_t)ret;
return 0;
}
static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip;
uint16_t reg_val;
int ret;
chip = container_of(gc, struct pca953x_chip, gpio_chip);
mutex_lock(&chip->i2c_lock);
reg_val = chip->reg_direction | (1u << off);
ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
if (ret)
goto exit;
chip->reg_direction = reg_val;
ret = 0;
exit:
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_direction_output(struct gpio_chip *gc,
unsigned off, int val)
{
struct pca953x_chip *chip;
uint16_t reg_val;
int ret;
chip = container_of(gc, struct pca953x_chip, gpio_chip);
mutex_lock(&chip->i2c_lock);
/* set output level */
if (val)
reg_val = chip->reg_output | (1u << off);
else
reg_val = chip->reg_output & ~(1u << off);
ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
if (ret)
goto exit;
chip->reg_output = reg_val;
/* then direction */
reg_val = chip->reg_direction & ~(1u << off);
ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
if (ret)
goto exit;
chip->reg_direction = reg_val;
ret = 0;
exit:
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip;
uint16_t reg_val;
int ret;
chip = container_of(gc, struct pca953x_chip, gpio_chip);
mutex_lock(&chip->i2c_lock);
ret = pca953x_read_reg(chip, PCA953X_INPUT, &reg_val);
mutex_unlock(&chip->i2c_lock);
if (ret < 0) {
/* NOTE: diagnostic already emitted; that's all we should
* do unless gpio_*_value_cansleep() calls become different
* from their nonsleeping siblings (and report faults).
*/
return 0;
}
return (reg_val & (1u << off)) ? 1 : 0;
}
static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
{
struct pca953x_chip *chip;
uint16_t reg_val;
int ret;
chip = container_of(gc, struct pca953x_chip, gpio_chip);
mutex_lock(&chip->i2c_lock);
if (val)
reg_val = chip->reg_output | (1u << off);
else
reg_val = chip->reg_output & ~(1u << off);
ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
if (ret)
goto exit;
chip->reg_output = reg_val;
exit:
mutex_unlock(&chip->i2c_lock);
}
static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
{
struct gpio_chip *gc;
gc = &chip->gpio_chip;
gc->direction_input = pca953x_gpio_direction_input;
gc->direction_output = pca953x_gpio_direction_output;
gc->get = pca953x_gpio_get_value;
gc->set = pca953x_gpio_set_value;
gc->can_sleep = 1;
gc->base = chip->gpio_start;
gc->ngpio = gpios;
gc->label = chip->client->name;
gpio: sysfs interface This adds a simple sysfs interface for GPIOs. /sys/class/gpio /export ... asks the kernel to export a GPIO to userspace /unexport ... to return a GPIO to the kernel /gpioN ... for each exported GPIO #N /value ... always readable, writes fail for input GPIOs /direction ... r/w as: in, out (default low); write high, low /gpiochipN ... for each gpiochip; #N is its first GPIO /base ... (r/o) same as N /label ... (r/o) descriptive, not necessarily unique /ngpio ... (r/o) number of GPIOs; numbered N .. N+(ngpio - 1) GPIOs claimed by kernel code may be exported by its owner using a new gpio_export() call, which should be most useful for driver debugging. Such exports may optionally be done without a "direction" attribute. Userspace may ask to take over a GPIO by writing to a sysfs control file, helping to cope with incomplete board support or other "one-off" requirements that don't merit full kernel support: echo 23 > /sys/class/gpio/export ... will gpio_request(23, "sysfs") and gpio_export(23); use /sys/class/gpio/gpio-23/direction to (re)configure it, when that GPIO can be used as both input and output. echo 23 > /sys/class/gpio/unexport ... will gpio_free(23), when it was exported as above The extra D-space footprint is a few hundred bytes, except for the sysfs resources associated with each exported GPIO. The additional I-space footprint is about two thirds of the current size of gpiolib (!). Since no /dev node creation is involved, no "udev" support is needed. Related changes: * This adds a device pointer to "struct gpio_chip". When GPIO providers initialize that, sysfs gpio class devices become children of that device instead of being "virtual" devices. * The (few) gpio_chip providers which have such a device node have been updated. * Some gpio_chip drivers also needed to update their module "owner" field ... for which missing kerneldoc was added. * Some gpio_chips don't support input GPIOs. Those GPIOs are now flagged appropriately when the chip is registered. Based on previous patches, and discussion both on and off LKML. A Documentation/ABI/testing/sysfs-gpio update is ready to submit once this merges to mainline. [akpm@linux-foundation.org: a few maintenance build fixes] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 08:46:07 +00:00
gc->dev = &chip->client->dev;
gc->owner = THIS_MODULE;
gc->names = chip->names;
}
#ifdef CONFIG_GPIO_PCA953X_IRQ
static int pca953x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip;
chip = container_of(gc, struct pca953x_chip, gpio_chip);
return chip->irq_base + off;
}
static void pca953x_irq_mask(struct irq_data *d)
{
struct pca953x_chip *chip = irq_data_get_irq_chip_data(d);
chip->irq_mask &= ~(1 << (d->irq - chip->irq_base));
}
static void pca953x_irq_unmask(struct irq_data *d)
{
struct pca953x_chip *chip = irq_data_get_irq_chip_data(d);
chip->irq_mask |= 1 << (d->irq - chip->irq_base);
}
static void pca953x_irq_bus_lock(struct irq_data *d)
{
struct pca953x_chip *chip = irq_data_get_irq_chip_data(d);
mutex_lock(&chip->irq_lock);
}
static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
{
struct pca953x_chip *chip = irq_data_get_irq_chip_data(d);
uint16_t new_irqs;
uint16_t level;
/* Look for any newly setup interrupt */
new_irqs = chip->irq_trig_fall | chip->irq_trig_raise;
new_irqs &= ~chip->reg_direction;
while (new_irqs) {
level = __ffs(new_irqs);
pca953x_gpio_direction_input(&chip->gpio_chip, level);
new_irqs &= ~(1 << level);
}
mutex_unlock(&chip->irq_lock);
}
static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
{
struct pca953x_chip *chip = irq_data_get_irq_chip_data(d);
uint16_t level = d->irq - chip->irq_base;
uint16_t mask = 1 << level;
if (!(type & IRQ_TYPE_EDGE_BOTH)) {
dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
d->irq, type);
return -EINVAL;
}
if (type & IRQ_TYPE_EDGE_FALLING)
chip->irq_trig_fall |= mask;
else
chip->irq_trig_fall &= ~mask;
if (type & IRQ_TYPE_EDGE_RISING)
chip->irq_trig_raise |= mask;
else
chip->irq_trig_raise &= ~mask;
return 0;
}
static struct irq_chip pca953x_irq_chip = {
.name = "pca953x",
.irq_mask = pca953x_irq_mask,
.irq_unmask = pca953x_irq_unmask,
.irq_bus_lock = pca953x_irq_bus_lock,
.irq_bus_sync_unlock = pca953x_irq_bus_sync_unlock,
.irq_set_type = pca953x_irq_set_type,
};
static uint16_t pca953x_irq_pending(struct pca953x_chip *chip)
{
uint16_t cur_stat;
uint16_t old_stat;
uint16_t pending;
uint16_t trigger;
int ret;
ret = pca953x_read_reg(chip, PCA953X_INPUT, &cur_stat);
if (ret)
return 0;
/* Remove output pins from the equation */
cur_stat &= chip->reg_direction;
old_stat = chip->irq_stat;
trigger = (cur_stat ^ old_stat) & chip->irq_mask;
if (!trigger)
return 0;
chip->irq_stat = cur_stat;
pending = (old_stat & chip->irq_trig_fall) |
(cur_stat & chip->irq_trig_raise);
pending &= trigger;
return pending;
}
static irqreturn_t pca953x_irq_handler(int irq, void *devid)
{
struct pca953x_chip *chip = devid;
uint16_t pending;
uint16_t level;
pending = pca953x_irq_pending(chip);
if (!pending)
return IRQ_HANDLED;
do {
level = __ffs(pending);
generic_handle_irq(level + chip->irq_base);
pending &= ~(1 << level);
} while (pending);
return IRQ_HANDLED;
}
static int pca953x_irq_setup(struct pca953x_chip *chip,
const struct i2c_device_id *id)
{
struct i2c_client *client = chip->client;
struct pca953x_platform_data *pdata = client->dev.platform_data;
int ret;
if (pdata->irq_base != -1
&& (id->driver_data & PCA953X_INT)) {
int lvl;
ret = pca953x_read_reg(chip, PCA953X_INPUT,
&chip->irq_stat);
if (ret)
goto out_failed;
/*
* There is no way to know which GPIO line generated the
* interrupt. We have to rely on the previous read for
* this purpose.
*/
chip->irq_stat &= chip->reg_direction;
chip->irq_base = pdata->irq_base;
mutex_init(&chip->irq_lock);
for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) {
int irq = lvl + chip->irq_base;
set_irq_chip_data(irq, chip);
set_irq_chip_and_handler(irq, &pca953x_irq_chip,
handle_edge_irq);
#ifdef CONFIG_ARM
set_irq_flags(irq, IRQF_VALID);
#else
set_irq_noprobe(irq);
#endif
}
ret = request_threaded_irq(client->irq,
NULL,
pca953x_irq_handler,
IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
dev_name(&client->dev), chip);
if (ret) {
dev_err(&client->dev, "failed to request irq %d\n",
client->irq);
goto out_failed;
}
chip->gpio_chip.to_irq = pca953x_gpio_to_irq;
}
return 0;
out_failed:
chip->irq_base = -1;
return ret;
}
static void pca953x_irq_teardown(struct pca953x_chip *chip)
{
if (chip->irq_base != -1)
free_irq(chip->client->irq, chip);
}
#else /* CONFIG_GPIO_PCA953X_IRQ */
static int pca953x_irq_setup(struct pca953x_chip *chip,
const struct i2c_device_id *id)
{
struct i2c_client *client = chip->client;
struct pca953x_platform_data *pdata = client->dev.platform_data;
if (pdata->irq_base != -1 && (id->driver_data & PCA953X_INT))
dev_warn(&client->dev, "interrupt support not compiled in\n");
return 0;
}
static void pca953x_irq_teardown(struct pca953x_chip *chip)
{
}
#endif
/*
* Handlers for alternative sources of platform_data
*/
#ifdef CONFIG_OF_GPIO
/*
* Translate OpenFirmware node properties into platform_data
*/
static struct pca953x_platform_data *
pca953x_get_alt_pdata(struct i2c_client *client)
{
struct pca953x_platform_data *pdata;
struct device_node *node;
const __be32 *val;
int size;
node = client->dev.of_node;
if (node == NULL)
return NULL;
pdata = kzalloc(sizeof(struct pca953x_platform_data), GFP_KERNEL);
if (pdata == NULL) {
dev_err(&client->dev, "Unable to allocate platform_data\n");
return NULL;
}
pdata->gpio_base = -1;
val = of_get_property(node, "linux,gpio-base", &size);
if (val) {
if (size != sizeof(*val))
dev_warn(&client->dev, "%s: wrong linux,gpio-base\n",
node->full_name);
else
pdata->gpio_base = be32_to_cpup(val);
}
val = of_get_property(node, "polarity", NULL);
if (val)
pdata->invert = *val;
return pdata;
}
#else
static struct pca953x_platform_data *
pca953x_get_alt_pdata(struct i2c_client *client)
{
return NULL;
}
#endif
static int __devinit pca953x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct pca953x_platform_data *pdata;
struct pca953x_chip *chip;
int ret;
chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
pdata = client->dev.platform_data;
if (pdata == NULL) {
pdata = pca953x_get_alt_pdata(client);
/*
* Unlike normal platform_data, this is allocated
* dynamically and must be freed in the driver
*/
chip->dyn_pdata = pdata;
}
if (pdata == NULL) {
dev_dbg(&client->dev, "no platform data\n");
ret = -EINVAL;
goto out_failed;
}
chip->client = client;
chip->gpio_start = pdata->gpio_base;
chip->names = pdata->names;
mutex_init(&chip->i2c_lock);
/* initialize cached registers from their original values.
* we can't share this chip with another i2c master.
*/
pca953x_setup_gpio(chip, id->driver_data & PCA953X_GPIOS);
ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
if (ret)
goto out_failed;
ret = pca953x_read_reg(chip, PCA953X_DIRECTION, &chip->reg_direction);
if (ret)
goto out_failed;
/* set platform specific polarity inversion */
ret = pca953x_write_reg(chip, PCA953X_INVERT, pdata->invert);
if (ret)
goto out_failed;
ret = pca953x_irq_setup(chip, id);
if (ret)
goto out_failed;
ret = gpiochip_add(&chip->gpio_chip);
if (ret)
goto out_failed;
if (pdata->setup) {
ret = pdata->setup(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
if (ret < 0)
dev_warn(&client->dev, "setup failed, %d\n", ret);
}
i2c_set_clientdata(client, chip);
return 0;
out_failed:
pca953x_irq_teardown(chip);
kfree(chip->dyn_pdata);
kfree(chip);
return ret;
}
static int pca953x_remove(struct i2c_client *client)
{
struct pca953x_platform_data *pdata = client->dev.platform_data;
struct pca953x_chip *chip = i2c_get_clientdata(client);
int ret = 0;
if (pdata->teardown) {
ret = pdata->teardown(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
if (ret < 0) {
dev_err(&client->dev, "%s failed, %d\n",
"teardown", ret);
return ret;
}
}
ret = gpiochip_remove(&chip->gpio_chip);
if (ret) {
dev_err(&client->dev, "%s failed, %d\n",
"gpiochip_remove()", ret);
return ret;
}
pca953x_irq_teardown(chip);
kfree(chip->dyn_pdata);
kfree(chip);
return 0;
}
static struct i2c_driver pca953x_driver = {
.driver = {
.name = "pca953x",
},
.probe = pca953x_probe,
.remove = pca953x_remove,
.id_table = pca953x_id,
};
static int __init pca953x_init(void)
{
return i2c_add_driver(&pca953x_driver);
}
/* register after i2c postcore initcall and before
* subsys initcalls that may rely on these GPIOs
*/
subsys_initcall(pca953x_init);
static void __exit pca953x_exit(void)
{
i2c_del_driver(&pca953x_driver);
}
module_exit(pca953x_exit);
MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
MODULE_LICENSE("GPL");