- Platform now passes a new platform structure, i2c_bit_platform_data, to the driver instead of passing i2c_algo_bit_data Signed-off-by: Eran Duchan <pavius@xxxxxxxxx> --- drivers/i2c/busses/Kconfig | 10 +++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-bit-platform.c | 120 +++++++++++++++++++++++++++++++++ include/linux/i2c-bit-platform.h | 35 ++++++++++ 4 files changed, 166 insertions(+), 0 deletions(-) create mode 100644 drivers/i2c/busses/i2c-bit-platform.c create mode 100644 include/linux/i2c-bit-platform.h diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 3a6321c..f6c6b8c 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -365,6 +365,16 @@ config I2C_GPIO This is a very simple bitbanging I2C driver utilizing the arch-neutral GPIO API to control the SCL and SDA lines. +config I2C_BIT_PLATFORM + tristate "I2c-bit-algo as platform device" + select I2C_ALGOBIT + help + An I2C bus adapter which delegates the bit-algo callback registration + to the platform. Useful in cases where existing adapters such as + i2c-gpio are too slow. Keep in mind that no resource locking of any kind + is performed by the adapter or algo, so any such contention must be + handled by the platform. + config I2C_HIGHLANDER tristate "Highlander FPGA SMBus interface" depends on SH_HIGHLANDER diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 84cb16a..65bced4 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_I2C_CPM) += i2c-cpm.o obj-$(CONFIG_I2C_DAVINCI) += i2c-davinci.o obj-$(CONFIG_I2C_DESIGNWARE) += i2c-designware.o obj-$(CONFIG_I2C_GPIO) += i2c-gpio.o +obj-$(CONFIG_I2C_BIT_PLATFORM) += i2c-bit-platform.o obj-$(CONFIG_I2C_HIGHLANDER) += i2c-highlander.o obj-$(CONFIG_I2C_IBM_IIC) += i2c-ibm_iic.o obj-$(CONFIG_I2C_IMX) += i2c-imx.o diff --git a/drivers/i2c/busses/i2c-bit-platform.c b/drivers/i2c/busses/i2c-bit-platform.c new file mode 100644 index 0000000..c1f4402 --- /dev/null +++ b/drivers/i2c/busses/i2c-bit-platform.c @@ -0,0 +1,120 @@ +/* + i2c-bit-algo as platform device + Delegates the bit-algo callback registration to the platform + + Copyright (C) 2011 Eran Duchan <pavius@xxxxxxxxx> + + 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, or + (at your option) any later version. +*/ + +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> +#include <linux/i2c-bit-platform.h> +#include <linux/slab.h> + +static int __devinit i2c_bit_platform_probe(struct platform_device *pdev) +{ + struct i2c_bit_platform_data *pdata; + struct i2c_algo_bit_data *bit_data; + struct i2c_adapter *adap; + int ret; + + if (pdev->dev.platform_data == NULL) + ret = -ENXIO; + + pdata = pdev->dev.platform_data; + + ret = -ENOMEM; + adap = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL); + if (adap == NULL) + goto err_alloc_adap; + bit_data = kzalloc(sizeof(struct i2c_algo_bit_data), GFP_KERNEL); + if (bit_data == NULL) + goto err_alloc_bit_data; + + bit_data->data = pdata->data; + bit_data->setsda = pdata->setsda; + bit_data->setscl = pdata->setscl; + bit_data->getsda = pdata->getsda; + bit_data->getscl = pdata->getscl; + bit_data->udelay = pdata->udelay; + bit_data->timeout = pdata->timeout; + + adap->owner = THIS_MODULE; + adap->algo_data = bit_data; + adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + adap->dev.parent = &pdev->dev; + + snprintf(adap->name, sizeof(adap->name), "i2c-bit-platform%d", + pdev->id); + adap->name[sizeof(adap->name) - 1] = '\0'; + + /* + * If "dev->id" is negative we consider it as zero. + * The reason to do so is to avoid sysfs names that only make + * sense when there are multiple adapters. + */ + adap->nr = (pdev->id != -1) ? pdev->id : 0; + ret = i2c_bit_add_numbered_bus(adap); + if (ret) + goto err_add_bus; + + platform_set_drvdata(pdev, adap); + + return 0; + +err_add_bus: + kfree(bit_data); +err_alloc_bit_data: + kfree(adap); +err_alloc_adap: + return ret; +} + +static int __devexit i2c_bit_platform_remove(struct platform_device *pdev) +{ + struct i2c_adapter *adap; + + adap = platform_get_drvdata(pdev); + + i2c_del_adapter(adap); + + kfree(adap->algo_data); + kfree(adap); + + return 0; +} + +static struct platform_driver i2c_bit_platform_driver = { + .driver = { + .name = "i2c-bit-platform", + .owner = THIS_MODULE, + }, + .probe = i2c_bit_platform_probe, + .remove = __devexit_p(i2c_bit_platform_remove), +}; + +static int __init i2c_bit_platform_init(void) +{ + int ret; + + ret = platform_driver_register(&i2c_bit_platform_driver); + if (ret) + printk(KERN_ERR "i2c-bit-platform: probe failed: %d\n", ret); + + return ret; +} +subsys_initcall(i2c_bit_platform_init); + +static void __exit i2c_bit_platform_exit(void) +{ + platform_driver_unregister(&i2c_bit_platform_driver); +} +module_exit(i2c_bit_platform_exit); + +MODULE_AUTHOR("Eran Duchan <pavius@xxxxxxxxx>"); +MODULE_DESCRIPTION("Thin platform adapter for i2c-bit-algo"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/i2c-bit-platform.h b/include/linux/i2c-bit-platform.h new file mode 100644 index 0000000..e3b601b --- /dev/null +++ b/include/linux/i2c-bit-platform.h @@ -0,0 +1,35 @@ +/* + * i2c-bit-platform interface to platform code + * + * Copyright (C) 2011 Eran Duchan <pavius@xxxxxxxxx> + * + * 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. + */ +#ifndef _LINUX_I2C_BIT_PLATFORM_H +#define _LINUX_I2C_BIT_PLATFORM_H + +/** + * struct i2c_bit_platform_data - Platform-dependent data for + * i2c-bit-platform + * @data: to be passed to callbacks, untouched + * @setsda: callback to set SDA line + * @setscl: callback to set SCL line + * @getsda: callback to get SDA line + * @getscl: callback to get SCL line + * @udelay: signal toggle delay. SCL frequency is (500 / udelay) kHz + * @timeout: clock stretching timeout in jiffies. If the slave keeps + * SCL low for longer than this, the transfer will time out. + */ +struct i2c_bit_platform_data { + void *data; + void (*setsda) (void *data, int state); + void (*setscl) (void *data, int state); + int (*getsda) (void *data); + int (*getscl) (void *data); + int udelay; + int timeout; +}; + +#endif /* _LINUX_I2C_BIT_PLATFORM_H */ -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html