Initial import

1 files changed, 290 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c
new file mode 100644
index 000000000..3bd2e7d06
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pca-platform.c
@@ -0,0 +1,290 @@
+/*
+ *  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/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 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);
+	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 i2c_pca_pf_remove(struct platform_device *pdev)
+{
+	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
+
+	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 = i2c_pca_pf_remove,
+	.driver = {
+		.name = "i2c-pca-platform",
+	},
+};
+
+module_platform_driver(i2c_pca_pf_driver);
+
+MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
+MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
+MODULE_LICENSE("GPL");