From bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9f Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Tue, 1 May 2007 23:26:34 +0200 Subject: [PATCH] i2c: New Simtec I2C bus driver Platform driver for the Simtec CPLD based simple I2C logic. Signed-off-by: Ben Dooks Signed-off-by: Jean Delvare --- drivers/i2c/busses/Kconfig | 12 +++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-simtec.c | 186 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 199 insertions(+) create mode 100644 drivers/i2c/busses/i2c-simtec.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 33a8a67..2178c9b 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -413,6 +413,18 @@ config I2C_SIBYTE help Supports the SiByte SOC on-chip I2C interfaces (2 channels). +config I2C_SIMTEC + tristate "Simtec Generic I2C interface" + select I2C_ALGOBIT + help + If you say yes to this option, support will be inclyded for + the Simtec Generic I2C interface. This driver is for the + simple I2C bus used on newer Simtec products for general + I2C, such as DDC on the Simtec BBD2016A. + + This driver can also be build as a module. If so, the module + will be called i2c-simtec. + config SCx200_I2C tristate "NatSemi SCx200 I2C using GPIO pins" depends on SCx200_GPIO diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 5689165..3a020ea 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_I2C_RPXLITE) += i2c-rpx.o obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o obj-$(CONFIG_I2C_SAVAGE4) += i2c-savage4.o obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o +obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o obj-$(CONFIG_I2C_SIS5595) += i2c-sis5595.o obj-$(CONFIG_I2C_SIS630) += i2c-sis630.o obj-$(CONFIG_I2C_SIS96X) += i2c-sis96x.o diff --git a/drivers/i2c/busses/i2c-simtec.c b/drivers/i2c/busses/i2c-simtec.c new file mode 100644 index 0000000..10af8d3 --- /dev/null +++ b/drivers/i2c/busses/i2c-simtec.c @@ -0,0 +1,186 @@ +/* + * Copyright (C) 2005 Simtec Electronics + * Ben Dooks + * + * Simtec Generic I2C Controller + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +#include +#include +#include +#include +#include + +#include +#include + +#include + +struct simtec_i2c_data { + struct resource *ioarea; + void __iomem *reg; + struct i2c_adapter adap; + struct i2c_algo_bit_data bit; +}; + +#define CMD_SET_SDA (1<<2) +#define CMD_SET_SCL (1<<3) + +#define STATE_SDA (1<<0) +#define STATE_SCL (1<<1) + +/* i2c bit-bus functions */ + +static void simtec_i2c_setsda(void *pw, int state) +{ + struct simtec_i2c_data *pd = pw; + writeb(CMD_SET_SDA | (state ? STATE_SDA : 0), pd->reg); +} + +static void simtec_i2c_setscl(void *pw, int state) +{ + struct simtec_i2c_data *pd = pw; + writeb(CMD_SET_SCL | (state ? STATE_SCL : 0), pd->reg); +} + +static int simtec_i2c_getsda(void *pw) +{ + struct simtec_i2c_data *pd = pw; + return readb(pd->reg) & STATE_SDA ? 1 : 0; +} + +static int simtec_i2c_getscl(void *pw) +{ + struct simtec_i2c_data *pd = pw; + return readb(pd->reg) & STATE_SCL ? 1 : 0; +} + +/* device registration */ + +static int simtec_i2c_probe(struct platform_device *dev) +{ + struct simtec_i2c_data *pd; + struct resource *res; + int size; + int ret; + + pd = kzalloc(sizeof(struct simtec_i2c_data), GFP_KERNEL); + if (pd == NULL) { + dev_err(&dev->dev, "cannot allocate private data\n"); + return -ENOMEM; + } + + platform_set_drvdata(dev, pd); + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(&dev->dev, "cannot find IO resource\n"); + ret = -ENOENT; + goto err; + } + + size = (res->end-res->start)+1; + + pd->ioarea = request_mem_region(res->start, size, dev->name); + if (pd->ioarea == NULL) { + dev_err(&dev->dev, "cannot request IO\n"); + ret = -ENXIO; + goto err; + } + + pd->reg = ioremap(res->start, size); + if (pd->reg == NULL) { + dev_err(&dev->dev, "cannot map IO\n"); + ret = -ENXIO; + goto err_res; + } + + /* setup the private data */ + + pd->adap.owner = THIS_MODULE; + pd->adap.algo_data = &pd->bit; + pd->adap.dev.parent = &dev->dev; + + strlcpy(pd->adap.name, "Simtec I2C", sizeof(pd->adap.name)); + + pd->bit.data = pd; + pd->bit.setsda = simtec_i2c_setsda; + pd->bit.setscl = simtec_i2c_setscl; + pd->bit.getsda = simtec_i2c_getsda; + pd->bit.getscl = simtec_i2c_getscl; + pd->bit.timeout = HZ; + pd->bit.udelay = 20; + + ret = i2c_bit_add_bus(&pd->adap); + if (ret) + goto err_all; + + return 0; + + err_all: + iounmap(pd->reg); + + err_res: + release_resource(pd->ioarea); + kfree(pd->ioarea); + + err: + kfree(pd); + return ret; +} + +static int simtec_i2c_remove(struct platform_device *dev) +{ + struct simtec_i2c_data *pd = platform_get_drvdata(dev); + + i2c_del_adapter(&pd->adap); + + iounmap(pd->reg); + release_resource(pd->ioarea); + kfree(pd->ioarea); + kfree(pd); + + return 0; +} + + +/* device driver */ + +static struct platform_driver simtec_i2c_driver = { + .driver = { + .name = "simtec-i2c", + .owner = THIS_MODULE, + }, + .probe = simtec_i2c_probe, + .remove = simtec_i2c_remove, +}; + +static int __init i2c_adap_simtec_init(void) +{ + return platform_driver_register(&simtec_i2c_driver); +} + +static void __exit i2c_adap_simtec_exit(void) +{ + platform_driver_unregister(&simtec_i2c_driver); +} + +module_init(i2c_adap_simtec_init); +module_exit(i2c_adap_simtec_exit); + +MODULE_DESCRIPTION("Simtec Generic I2C Bus driver"); +MODULE_AUTHOR("Ben Dooks "); +MODULE_LICENSE("GPL"); -- 2.7.4