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linux/drivers/i2c/busses/i2c-pca-platform.c
Karol Lewandowski 44454baa7c i2c: Dynamically assign adapter id if it wasn't explictly specified 
Commit 488bf314b ("i2c: Allow i2c_add_numbered_adapter() to assign a
bus id") reworked i2c_add_numbered_adapter() to call i2c_add_adapter()
if requested bus was -1.

This allows to simplify driver's initialization procedure by using
just one function for static and dynamic adapter id registration.

This patch updates few more drivers (missed out in original patch)
to use this functionality.

Signed-off-by: Karol Lewandowski <k.lewandowsk@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-05-12 14:28:11 +02:00

294 lines
6.5 KiB
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/*
* i2c_pca_platform.c
*
* Platform driver for the PCA9564 I2C controller.
*
* Copyright (C) 2008 Pengutronix
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/i2c-algo-pca.h>
#include <linux/i2c-pca-platform.h>
#include <linux/gpio.h>
#include <linux/io.h>
#include <asm/irq.h>
struct i2c_pca_pf_data {
void __iomem *reg_base;
int irq; /* if 0, use polling */
int gpio;
wait_queue_head_t wait;
struct i2c_adapter adap;
struct i2c_algo_pca_data algo_data;
unsigned long io_base;
unsigned long io_size;
};
/* Read/Write functions for different register alignments */
static int i2c_pca_pf_readbyte8(void *pd, int reg)
{
struct i2c_pca_pf_data *i2c = pd;
return ioread8(i2c->reg_base + reg);
}
static int i2c_pca_pf_readbyte16(void *pd, int reg)
{
struct i2c_pca_pf_data *i2c = pd;
return ioread8(i2c->reg_base + reg * 2);
}
static int i2c_pca_pf_readbyte32(void *pd, int reg)
{
struct i2c_pca_pf_data *i2c = pd;
return ioread8(i2c->reg_base + reg * 4);
}
static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
{
struct i2c_pca_pf_data *i2c = pd;
iowrite8(val, i2c->reg_base + reg);
}
static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
{
struct i2c_pca_pf_data *i2c = pd;
iowrite8(val, i2c->reg_base + reg * 2);
}
static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
{
struct i2c_pca_pf_data *i2c = pd;
iowrite8(val, i2c->reg_base + reg * 4);
}
static int i2c_pca_pf_waitforcompletion(void *pd)
{
struct i2c_pca_pf_data *i2c = pd;
unsigned long timeout;
long ret;
if (i2c->irq) {
ret = wait_event_timeout(i2c->wait,
i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
& I2C_PCA_CON_SI, i2c->adap.timeout);
} else {
/* Do polling */
timeout = jiffies + i2c->adap.timeout;
do {
ret = time_before(jiffies, timeout);
if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
& I2C_PCA_CON_SI)
break;
udelay(100);
} while (ret);
}
return ret > 0;
}
static void i2c_pca_pf_dummyreset(void *pd)
{
struct i2c_pca_pf_data *i2c = pd;
printk(KERN_WARNING "%s: No reset-pin found. Chip may get stuck!\n",
i2c->adap.name);
}
static void i2c_pca_pf_resetchip(void *pd)
{
struct i2c_pca_pf_data *i2c = pd;
gpio_set_value(i2c->gpio, 0);
ndelay(100);
gpio_set_value(i2c->gpio, 1);
}
static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
{
struct i2c_pca_pf_data *i2c = dev_id;
if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
return IRQ_NONE;
wake_up(&i2c->wait);
return IRQ_HANDLED;
}
static int __devinit i2c_pca_pf_probe(struct platform_device *pdev)
{
struct i2c_pca_pf_data *i2c;
struct resource *res;
struct i2c_pca9564_pf_platform_data *platform_data =
pdev->dev.platform_data;
int ret = 0;
int irq;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_irq(pdev, 0);
/* If irq is 0, we do polling. */
if (res == NULL) {
ret = -ENODEV;
goto e_print;
}
if (!request_mem_region(res->start, resource_size(res), res->name)) {
ret = -ENOMEM;
goto e_print;
}
i2c = kzalloc(sizeof(struct i2c_pca_pf_data), GFP_KERNEL);
if (!i2c) {
ret = -ENOMEM;
goto e_alloc;
}
init_waitqueue_head(&i2c->wait);
i2c->reg_base = ioremap(res->start, resource_size(res));
if (!i2c->reg_base) {
ret = -ENOMEM;
goto e_remap;
}
i2c->io_base = res->start;
i2c->io_size = resource_size(res);
i2c->irq = irq;
i2c->adap.nr = pdev->id;
i2c->adap.owner = THIS_MODULE;
snprintf(i2c->adap.name, sizeof(i2c->adap.name),
"PCA9564/PCA9665 at 0x%08lx",
(unsigned long) res->start);
i2c->adap.algo_data = &i2c->algo_data;
i2c->adap.dev.parent = &pdev->dev;
if (platform_data) {
i2c->adap.timeout = platform_data->timeout;
i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
i2c->gpio = platform_data->gpio;
} else {
i2c->adap.timeout = HZ;
i2c->algo_data.i2c_clock = 59000;
i2c->gpio = -1;
}
i2c->algo_data.data = i2c;
i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
case IORESOURCE_MEM_32BIT:
i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
break;
case IORESOURCE_MEM_16BIT:
i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
break;
case IORESOURCE_MEM_8BIT:
default:
i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
break;
}
/* Use gpio_is_valid() when in mainline */
if (i2c->gpio > -1) {
ret = gpio_request(i2c->gpio, i2c->adap.name);
if (ret == 0) {
gpio_direction_output(i2c->gpio, 1);
i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
} else {
printk(KERN_WARNING "%s: Registering gpio failed!\n",
i2c->adap.name);
i2c->gpio = ret;
}
}
if (irq) {
ret = request_irq(irq, i2c_pca_pf_handler,
IRQF_TRIGGER_FALLING, pdev->name, i2c);
if (ret)
goto e_reqirq;
}
if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
ret = -ENODEV;
goto e_adapt;
}
platform_set_drvdata(pdev, i2c);
printk(KERN_INFO "%s registered.\n", i2c->adap.name);
return 0;
e_adapt:
if (irq)
free_irq(irq, i2c);
e_reqirq:
if (i2c->gpio > -1)
gpio_free(i2c->gpio);
iounmap(i2c->reg_base);
e_remap:
kfree(i2c);
e_alloc:
release_mem_region(res->start, resource_size(res));
e_print:
printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
return ret;
}
static int __devexit i2c_pca_pf_remove(struct platform_device *pdev)
{
struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
i2c_del_adapter(&i2c->adap);
if (i2c->irq)
free_irq(i2c->irq, i2c);
if (i2c->gpio > -1)
gpio_free(i2c->gpio);
iounmap(i2c->reg_base);
release_mem_region(i2c->io_base, i2c->io_size);
kfree(i2c);
return 0;
}
static struct platform_driver i2c_pca_pf_driver = {
.probe = i2c_pca_pf_probe,
.remove = __devexit_p(i2c_pca_pf_remove),
.driver = {
.name = "i2c-pca-platform",
.owner = THIS_MODULE,
},
};
module_platform_driver(i2c_pca_pf_driver);
MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
MODULE_LICENSE("GPL");
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