I2C bus driver using ep93xx GPIOs. Signed-off-by: Lennert Buytenhek Index: linux-2.6.24/drivers/i2c/busses/Kconfig =================================================================== --- linux-2.6.24.orig/drivers/i2c/busses/Kconfig 2010-02-07 14:53:59.000000000 +0100 +++ linux-2.6.24/drivers/i2c/busses/Kconfig 2010-02-07 14:54:23.000000000 +0100 @@ -675,4 +675,16 @@ This driver can also be built as module. If so, the module will be called i2c-pmcmsp. +config I2C_EP93XX + tristate "Cirrus Logic EP93XX GPIO-based I2C interface" + depends on I2C && ARCH_EP93XX + select I2C_ALGOBIT + help + Say Y here if you have an Cirrus Logic EP93XX based + system and are using GPIO lines for an I2C bus. + + This support is also available as a module. If so, the module + will be called i2c-ep93xx. + + endmenu Index: linux-2.6.24/drivers/i2c/busses/Makefile =================================================================== --- linux-2.6.24.orig/drivers/i2c/busses/Makefile 2010-02-07 14:53:59.000000000 +0100 +++ linux-2.6.24/drivers/i2c/busses/Makefile 2010-02-07 14:54:23.000000000 +0100 @@ -53,6 +53,7 @@ obj-$(CONFIG_I2C_VOODOO3) += i2c-voodoo3.o obj-$(CONFIG_SCx200_ACB) += scx200_acb.o obj-$(CONFIG_SCx200_I2C) += scx200_i2c.o +obj-$(CONFIG_I2C_EP93XX) += i2c-ep93xx.o ifeq ($(CONFIG_I2C_DEBUG_BUS),y) EXTRA_CFLAGS += -DDEBUG Index: linux-2.6.24/drivers/i2c/busses/i2c-ep93xx.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ linux-2.6.24/drivers/i2c/busses/i2c-ep93xx.c 2010-02-07 14:54:23.000000000 +0100 @@ -0,0 +1,159 @@ +/* + * EP93XX I2C bus driver. + * Copyright (C) 2007 Lennert Buytenhek + * + * An I2C bus driver for the Cirrus Logic EP93xx SoC. + * + * Based on an earlier version by Alessandro Zummo. + */ + +#include +#include +#include +#include +#include +#include +#include + +struct ep93xx_i2c_priv { + struct ep93xx_i2c_data *data; + struct i2c_adapter adapter; + struct i2c_algo_bit_data algo_data; + int sda; + int scl; +}; + + +static void ep93xx_bit_setsda(void *cookie, int val) +{ + struct ep93xx_i2c_priv *priv = cookie; + + if (val) { + gpio_line_config(priv->data->sda_pin, GPIO_IN); + if (priv->scl && !priv->sda && priv->data->stop != NULL) + priv->data->stop(priv->data->cookie); + priv->sda = 1; + } else { + if (priv->scl && priv->sda && priv->data->start != NULL) + priv->data->start(priv->data->cookie); + gpio_line_config(priv->data->sda_pin, GPIO_OUT); + gpio_line_set(priv->data->sda_pin, 0); + priv->sda = 0; + } +} + +static void ep93xx_bit_setscl(void *cookie, int val) +{ + struct ep93xx_i2c_priv *priv = cookie; + + if (val) { + gpio_line_config(priv->data->scl_pin, GPIO_IN); + priv->scl = 1; + } else { + gpio_line_config(priv->data->scl_pin, GPIO_OUT); + gpio_line_set(priv->data->scl_pin, 0); + priv->scl = 0; + } +} + +static int ep93xx_bit_getsda(void *cookie) +{ + struct ep93xx_i2c_priv *priv = cookie; + + if (priv->sda == 0) + BUG(); + + return gpio_line_get(priv->data->sda_pin); +} + +static int ep93xx_bit_getscl(void *cookie) +{ + struct ep93xx_i2c_priv *priv = cookie; + + if (priv->scl == 0) + BUG(); + + return gpio_line_get(priv->data->scl_pin); +} + + +static int ep93xx_i2c_probe(struct platform_device *pdev) +{ + struct ep93xx_i2c_priv *priv; + int err; + + priv = kzalloc(sizeof(struct ep93xx_i2c_priv), GFP_KERNEL); + if (priv == NULL) + return -ENOMEM; + + priv->data = pdev->dev.platform_data; + + strlcpy(priv->adapter.name, pdev->dev.driver->name, I2C_NAME_SIZE); + priv->adapter.algo_data = &priv->algo_data; + priv->adapter.class = I2C_CLASS_ALL; + priv->adapter.dev.parent = &pdev->dev; + + priv->algo_data.data = priv; + priv->algo_data.setsda = ep93xx_bit_setsda; + priv->algo_data.setscl = ep93xx_bit_setscl; + priv->algo_data.getsda = ep93xx_bit_getsda; + priv->algo_data.getscl = ep93xx_bit_getscl; + priv->algo_data.udelay = 10; + priv->algo_data.timeout = 100; + + priv->sda = 1; + gpio_line_config(priv->data->sda_pin, GPIO_IN); + + priv->scl = 1; + gpio_line_config(priv->data->scl_pin, GPIO_IN); + + err = i2c_bit_add_bus(&priv->adapter); + if (err) { + printk(KERN_ERR "ERROR: Could not install %s\n", + pdev->dev.bus_id); + kfree(priv); + return err; + } + + platform_set_drvdata(pdev, priv); + + return 0; +} + +static int ep93xx_i2c_remove(struct platform_device *pdev) +{ + struct ep93xx_i2c_priv *priv; + + priv = platform_get_drvdata(pdev); + i2c_del_adapter(&priv->adapter); + platform_set_drvdata(pdev, NULL); + kfree(priv); + + return 0; +} + +static struct platform_driver ep93xx_i2c_driver = { + .probe = ep93xx_i2c_probe, + .remove = ep93xx_i2c_remove, + .driver = { + .name = "ep93xx-i2c", + .owner = THIS_MODULE, + }, +}; + +static int __init ep93xx_i2c_init(void) +{ + return platform_driver_register(&ep93xx_i2c_driver); +} + +static void __exit ep93xx_i2c_exit(void) +{ + platform_driver_unregister(&ep93xx_i2c_driver); +} + +module_init(ep93xx_i2c_init); +module_exit(ep93xx_i2c_exit); + +MODULE_AUTHOR("Lennert Buytenhek "); +MODULE_DESCRIPTION("GPIO-based I2C adapter for EP93XX systems"); +MODULE_LICENSE("GPL"); Index: linux-2.6.24/include/asm-arm/arch-ep93xx/platform.h =================================================================== --- linux-2.6.24.orig/include/asm-arm/arch-ep93xx/platform.h 2010-02-07 14:53:59.000000000 +0100 +++ linux-2.6.24/include/asm-arm/arch-ep93xx/platform.h 2010-02-07 14:54:23.000000000 +0100 @@ -16,5 +16,13 @@ unsigned char phy_id; }; +struct ep93xx_i2c_data { + int sda_pin; + int scl_pin; + void *cookie; + void (*start)(void *); + void (*stop)(void *); +}; + #endif