| /* |
| * 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 >= 0 ? pdev->id : 0; |
| 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, i2c->adap.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, |
| }, |
| }; |
| |
| static int __init i2c_pca_pf_init(void) |
| { |
| return platform_driver_register(&i2c_pca_pf_driver); |
| } |
| |
| static void __exit i2c_pca_pf_exit(void) |
| { |
| platform_driver_unregister(&i2c_pca_pf_driver); |
| } |
| |
| MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>"); |
| MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver"); |
| MODULE_LICENSE("GPL"); |
| |
| module_init(i2c_pca_pf_init); |
| module_exit(i2c_pca_pf_exit); |
| |