enhance the custom i2c-gpio driver (supports 4 buses from now on), update kernel configuration

SVN-Revision: 9244

target/linux/adm5120/files/drivers/i2c/busses/i2c-gpio-custom.c

@@ -6,6 +6,40 @@
  *  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.
+ *
+ * ---------------------------------------------------------------------------
+ *
+ *  The behaviour of this driver can be altered by setting some parameters
+ *  from the insmod command line.
+ *
+ *  The following parameters are adjustable:
+ *
+ *	bus0	These four arguments can be arrays of
+ *	bus1	1-8 unsigned integers as follows:
+ *	bus2
+ *	bus3	<id>,<sda>,<scl>,<udelay>,<timeout>,<sda_od>,<scl_od>,<scl_oo>
+ *
+ *  where:
+ *
+ *  <id>	ID to used as device_id for the corresponding bus (required)
+ *  <sda>	GPIO pin ID to used for SDA (required)
+ *  <scl>	GPIO pin ID to used for SCL (required)
+ *  <udelay>	signal toggle delay.
+ *  <timeout>	clock stretching timeout.
+ *  <sda_od>	SDA is configured as open drain.
+ *  <scl_od>	SCL is configured as open drain.
+ *  <scl_oo>	SCL output drivers cannot be turned off.
+ *
+ *  See include/i2c-gpio.h for more information about the parameters.
+ *
+ *  If this driver is built into the kernel, you can use the following kernel
+ *  command line parameters, with the same values as the corresponding module
+ *  parameters listed above:
+ *
+ *	i2c-gpio-custom.bus0
+ *	i2c-gpio-custom.bus1
+ *	i2c-gpio-custom.bus2
+ *	i2c-gpio-custom.bus3
  */
 
 #include <linux/kernel.h>
@@ -16,56 +50,141 @@
 #include <linux/i2c-gpio.h>
 
 #define DRV_NAME	"i2c-gpio-custom"
-#define DRV_DESC	"Custom GPIO I2C device driver"
+#define DRV_DESC	"Custom GPIO-based I2C driver"
+#define DRV_VERSION	"0.1.0"
 
-static unsigned int sda = CONFIG_I2C_GPIO_CUSTOM_SDA;
+#define PFX		DRV_NAME ": "
-static unsigned int scl = CONFIG_I2C_GPIO_CUSTOM_SCL;
-static int id = CONFIG_I2C_GPIO_CUSTOM_DEVICE_ID;
 
-module_param(sda, uint, S_IRUGO);
+#define BUS_PARAM_ID		0
-MODULE_PARM_DESC(sda, "GPIO pin for SDA");
+#define BUS_PARAM_SDA		1
+#define BUS_PARAM_SCL		2
+#define BUS_PARAM_UDELAY	3
+#define BUS_PARAM_TIMEOUT	4
+#define BUS_PARAM_SDA_OD	5
+#define BUS_PARAM_SCL_OD	6
+#define BUS_PARAM_SCL_OO	7
 
-module_param(scl, uint, S_IRUGO);
+#define BUS_PARAM_REQUIRED	3
-MODULE_PARM_DESC(scl, "GPIO pin for SCL");
+#define BUS_PARAM_COUNT		8
+#define BUS_COUNT_MAX		4
 
-module_param(id, int, S_IRUGO);
+static unsigned int bus0[BUS_PARAM_COUNT] __initdata;
-MODULE_PARM_DESC(id, "device id of the i2c-gpio device");
+static unsigned int bus1[BUS_PARAM_COUNT] __initdata;
+static unsigned int bus2[BUS_PARAM_COUNT] __initdata;
+static unsigned int bus3[BUS_PARAM_COUNT] __initdata;
 
-static struct i2c_gpio_platform_data i2c_data;
+static unsigned int bus_nump[BUS_COUNT_MAX] __initdata;
-static struct platform_device i2c_device;
 
-static void i2c_gpio_custom_release(struct platform_device *pdev)
+#define BUS_PARM_DESC \
+	" config -> id,sda,scl[,udelay,timeout,sda_od,scl_od,scl_oo]"
+
+module_param_array(bus0, uint, &bus_nump[0], 0);
+MODULE_PARM_DESC(bus0, "bus0" BUS_PARM_DESC);
+module_param_array(bus1, uint, &bus_nump[1], 0);
+MODULE_PARM_DESC(bus1, "bus1" BUS_PARM_DESC);
+module_param_array(bus2, uint, &bus_nump[2], 0);
+MODULE_PARM_DESC(bus2, "bus2" BUS_PARM_DESC);
+module_param_array(bus3, uint, &bus_nump[3], 0);
+MODULE_PARM_DESC(bus3, "bus3" BUS_PARM_DESC);
+
+static struct platform_device *devices[BUS_COUNT_MAX];
+static unsigned int nr_devices;
+
+static void i2c_gpio_custom_cleanup(void)
 {
-	/* nothing to do */
+	int i;
+
+	for (i = 0; i < nr_devices; i++)
+		if (devices[i])
+			platform_device_unregister(devices[i]);
+}
+
+static int __init i2c_gpio_custom_add_one(unsigned int id, unsigned int *params)
+{
+	struct platform_device *pdev;
+	struct i2c_gpio_platform_data pdata;
+	int err;
+
+	if (!bus_nump[id])
+		return 0;
+
+	if (bus_nump[id] < BUS_PARAM_REQUIRED) {
+		printk(KERN_ERR PFX "not enough parameters for bus%d\n", id);
+		err = -EINVAL;
+		goto err;
+	}
+
+	pdev = platform_device_alloc("i2c-gpio", params[BUS_PARAM_ID]);
+	if (!pdev) {
+		err = -ENOMEM;
+		goto err;
+	}
+
+	devices[nr_devices++] = pdev;
+
+	pdata.sda_pin = params[BUS_PARAM_SDA];
+	pdata.scl_pin = params[BUS_PARAM_SCL];
+	pdata.udelay = params[BUS_PARAM_UDELAY];
+	pdata.timeout = params[BUS_PARAM_TIMEOUT];
+	pdata.sda_is_open_drain = params[BUS_PARAM_SDA_OD] != 0;
+	pdata.scl_is_open_drain = params[BUS_PARAM_SCL_OD] != 0;
+	pdata.scl_is_output_only = params[BUS_PARAM_SCL_OO] != 0;
+
+	err = platform_device_add_data(pdev, &pdata, sizeof(pdata));
+	if (err)
+		goto err;
+
+	err = platform_device_register(pdev);
+	if (err)
+		goto err;
+
+	return 0;
+
+err:
+	return err;
 }
 
 static int __init i2c_gpio_custom_init(void)
 {
 	int err;
 
-	i2c_data.sda_pin = sda;
+	printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
-	i2c_data.scl_pin = scl;
 
-	i2c_device.name	= "i2c-gpio";
+	err = i2c_gpio_custom_add_one(0, bus0);
-	i2c_device.id	= id;
+	if (err) goto err;
 
-	i2c_device.dev.platform_data	= &i2c_data,
+	err = i2c_gpio_custom_add_one(1, bus1);
-	i2c_device.dev.release		= i2c_gpio_custom_release,
+	if (err) goto err;
 
-	err = platform_device_register(&i2c_device);
+	err = i2c_gpio_custom_add_one(2, bus2);
+	if (err) goto err;
 
+	err = i2c_gpio_custom_add_one(3, bus3);
+	if (err) goto err;
+
+	if (!nr_devices) {
+		printk(KERN_ERR PFX "no bus parameter(s) specified\n");
+		err = -ENODEV;
+		goto err;
+	}
+
+	return 0;
+
+err:
+	i2c_gpio_custom_cleanup();
 	return err;
 }
+module_init(i2c_gpio_custom_init);
 
 static void __exit i2c_gpio_custom_exit(void)
 {
-	platform_device_unregister(&i2c_device);
+	i2c_gpio_custom_cleanup();
 }
-
-module_init(i2c_gpio_custom_init);
 module_exit(i2c_gpio_custom_exit);
 
+
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org >");
 MODULE_DESCRIPTION(DRV_DESC);
+MODULE_VERSION(DRV_VERSION);
 

target/linux/adm5120/patches-2.6.22/300-i2c_gpio_custom.patch

@@ -1,42 +1,19 @@
 --- linux-2.6.22.4.orig/drivers/i2c/busses/Kconfig	2007-08-21 06:33:06.000000000 +0200
 +++ linux-2.6.22.4/drivers/i2c/busses/Kconfig	2007-10-09 12:53:13.000000000 +0200
-@@ -125,6 +125,40 @@
+@@ -125,6 +125,17 @@
  	  This is a very simple bitbanging I2C driver utilizing the
  	  arch-neutral GPIO API to control the SCL and SDA lines.
  
 +config I2C_GPIO_CUSTOM
-+	tristate "Custom GPIO-based I2C device"
++	tristate "Custom GPIO-based I2C driver"
 +	depends on GENERIC_GPIO
 +	select I2C_GPIO
 +	help
-+	  This is an I2C driver to register a custom i2c-gpio device.
++	  This is an I2C driver to register 1 to 4 custom I2C buses using 
++	  GPIO lines.
 +
 +	  This support is also available as a module.  If so, the module
-+	  will be called i2c-gpio-dev.
++	  will be called i2c-gpio-custom.
-+
-+config I2C_GPIO_CUSTOM_SDA
-+	int "Custom GPIO pin for SDA"
-+	depends on I2C_GPIO_CUSTOM
-+	default "0"
-+	help
-+	  Enter the GPIO pin number used for the SDA signal.  This value can
-+	  also be specified with a module parameter.
-+
-+config I2C_GPIO_CUSTOM_SCL
-+	int "Custom GPIO pin for SCL"
-+	depends on I2C_GPIO_CUSTOM
-+	default "1"
-+	help
-+	  Enter the GPIO pin number used for the SCL signal.  This value can
-+	  also be specified with a module parameter.
-+
-+config I2C_GPIO_CUSTOM_DEVICE_ID
-+	int "Custom GPIO device id"
-+	depends on I2C_GPIO_CUSTOM
-+	default	"0"
-+	help
-+	  Enter the number used for the device id of the custom i2c-gpio device.
-+	  This value can also be specified with a module parameter.
 +
  config I2C_HYDRA
  	tristate "CHRP Apple Hydra Mac I/O I2C interface"

target/linux/adm5120/router_be/config-2.6.22

@@ -73,15 +73,7 @@ CONFIG_HW_RANDOM=y
 CONFIG_HZ=250
 # CONFIG_HZ_100 is not set
 CONFIG_HZ_250=y
-CONFIG_I2C=m
+# CONFIG_I2C is not set
-CONFIG_I2C_ALGOBIT=m
-CONFIG_I2C_BOARDINFO=y
-CONFIG_I2C_CHARDEV=m
-CONFIG_I2C_GPIO=m
-CONFIG_I2C_GPIO_CUSTOM=m
-CONFIG_I2C_GPIO_CUSTOM_DEVICE_ID=0
-CONFIG_I2C_GPIO_CUSTOM_SCL=1
-CONFIG_I2C_GPIO_CUSTOM_SDA=0
 # CONFIG_IDE is not set
 CONFIG_INET6_XFRM_MODE_ROUTEOPTIMIZATION=m
 CONFIG_INITRAMFS_SOURCE=""
@@ -196,7 +188,6 @@ CONFIG_PCI_ADM5120=y
 CONFIG_RWSEM_GENERIC_SPINLOCK=y
 CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER=y
 CONFIG_SCSI_WAIT_SCAN=m
-# CONFIG_SENSORS_PC87360 is not set
 # CONFIG_SERIAL_8250 is not set
 # CONFIG_SERIAL_ADM5120 is not set
 CONFIG_SERIAL_AMBA_PL010=y

target/linux/adm5120/router_le/config-2.6.22

@@ -73,15 +73,7 @@ CONFIG_HW_RANDOM=y
 CONFIG_HZ=250
 # CONFIG_HZ_100 is not set
 CONFIG_HZ_250=y
-CONFIG_I2C=m
+# CONFIG_I2C is not set
-CONFIG_I2C_ALGOBIT=m
-CONFIG_I2C_BOARDINFO=y
-CONFIG_I2C_CHARDEV=m
-CONFIG_I2C_GPIO=m
-CONFIG_I2C_GPIO_CUSTOM=m
-CONFIG_I2C_GPIO_CUSTOM_DEVICE_ID=0
-CONFIG_I2C_GPIO_CUSTOM_SCL=1
-CONFIG_I2C_GPIO_CUSTOM_SDA=0
 # CONFIG_IDE is not set
 CONFIG_INET6_XFRM_MODE_ROUTEOPTIMIZATION=m
 CONFIG_INITRAMFS_SOURCE=""
@@ -206,7 +198,6 @@ CONFIG_PCI_ADM5120=y
 CONFIG_RWSEM_GENERIC_SPINLOCK=y
 CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER=y
 CONFIG_SCSI_WAIT_SCAN=m
-# CONFIG_SENSORS_PC87360 is not set
 # CONFIG_SERIAL_8250 is not set
 # CONFIG_SERIAL_ADM5120 is not set
 CONFIG_SERIAL_AMBA_PL010=y