Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  i2c_pca_platform.c
 *
 *  Platform driver for the PCA9564 I2C controller.
 *
 *  Copyright (C) 2008 Pengutronix
 *
 
 */
#include <linux/kernel.h>
#include <linux/module.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/platform_data/i2c-pca-platform.h>
#include <linux/gpio/consumer.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_device.h>
 
#include <asm/irq.h>
 
struct i2c_pca_pf_data {
<------>void __iomem			*reg_base;
<------>int				irq;	/* if 0, use polling */
<------>struct gpio_desc		*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;
 
<------>dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
}
 
static void i2c_pca_pf_resetchip(void *pd)
{
<------>struct i2c_pca_pf_data *i2c = pd;
 
<------>gpiod_set_value(i2c->gpio, 1);
<------>ndelay(100);
<------>gpiod_set_value(i2c->gpio, 0);
}
 
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 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 =
<------><------><------><------>dev_get_platdata(&pdev->dev);
<------>struct device_node *np = pdev->dev.of_node;
<------>int ret = 0;
<------>int irq;
 
<------>irq = platform_get_irq_optional(pdev, 0);
<------>/* If irq is 0, we do polling. */
<------>if (irq < 0)
<------><------>irq = 0;
 
<------>i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
<------>if (!i2c)
<------><------>return -ENOMEM;
 
<------>i2c->reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
<------>if (IS_ERR(i2c->reg_base))
<------><------>return PTR_ERR(i2c->reg_base);
 
 
<------>init_waitqueue_head(&i2c->wait);
 
<------>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;
<------>i2c->adap.dev.of_node = np;
 
<------>i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
<------>if (IS_ERR(i2c->gpio))
<------><------>return PTR_ERR(i2c->gpio);
 
<------>i2c->adap.timeout = HZ;
<------>ret = device_property_read_u32(&pdev->dev, "clock-frequency",
<------><------><------><------>       &i2c->algo_data.i2c_clock);
<------>if (ret)
<------><------>i2c->algo_data.i2c_clock = 59000;
 
<------>if (platform_data) {
<------><------>i2c->adap.timeout = platform_data->timeout;
<------><------>i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
<------>}
 
<------>i2c->algo_data.data = i2c;
<------>i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
<------>if (i2c->gpio)
<------><------>i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
<------>else
<------><------>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;
<------>}
 
<------>if (irq) {
<------><------>ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
<------><------><------>IRQF_TRIGGER_FALLING, pdev->name, i2c);
<------><------>if (ret)
<------><------><------>return ret;
<------>}
 
<------>ret = i2c_pca_add_numbered_bus(&i2c->adap);
<------>if (ret)
<------><------>return ret;
 
<------>platform_set_drvdata(pdev, i2c);
 
<------>dev_info(&pdev->dev, "registered.\n");
 
<------>return 0;
}
 
static int i2c_pca_pf_remove(struct platform_device *pdev)
{
<------>struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
 
<------>i2c_del_adapter(&i2c->adap);
 
<------>return 0;
}
 
#ifdef CONFIG_OF
static const struct of_device_id i2c_pca_of_match_table[] = {
<------>{ .compatible = "nxp,pca9564" },
<------>{ .compatible = "nxp,pca9665" },
<------>{},
};
MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
#endif
 
static struct platform_driver i2c_pca_pf_driver = {
<------>.probe = i2c_pca_pf_probe,
<------>.remove = i2c_pca_pf_remove,
<------>.driver = {
<------><------>.name = "i2c-pca-platform",
<------><------>.of_match_table = of_match_ptr(i2c_pca_of_match_table),
<------>},
};
 
module_platform_driver(i2c_pca_pf_driver);
 
MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
MODULE_LICENSE("GPL");