- 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 <[email protected]>
---
 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 <[email protected]>
+
+    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 <[email protected]>");
+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 <[email protected]>
+ *
+ * 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

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