hwmon/lm78: No longer use i2c-isa

Reimplement the ISA device support as a platform driver, so that we no
longer rely on i2c-isa.

Signed-off-by: Jean Delvare <khali@linux-fr.org>

2 files changed, 267 insertions, 111 deletions

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index d89bd5eb50ae..659a2abb3e90 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -291,7 +291,6 @@ config SENSORS_LM77
 config SENSORS_LM78
         tristate "National Semiconductor LM78 and compatibles"
         depends on HWMON && I2C
-        select I2C_ISA
         select HWMON_VID
         help
           If you say yes here you get support for National Semiconductor LM78,
diff --git a/drivers/hwmon/lm78.c b/drivers/hwmon/lm78.c
index 886786c33916..cfb08978459d 100644
--- a/drivers/hwmon/lm78.c
+++ b/drivers/hwmon/lm78.c
@@ -2,6 +2,7 @@
     lm78.c - Part of lm_sensors, Linux kernel modules for hardware
              monitoring
     Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> 
+    Copyright (c) 2007        Jean Delvare <khali@linux-fr.org>
 
     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
@@ -23,13 +24,17 @@
 #include <linux/slab.h>
 #include <linux/jiffies.h>
 #include <linux/i2c.h>
-#include <linux/i2c-isa.h>
+#include <linux/platform_device.h>
+#include <linux/ioport.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-vid.h>
 #include <linux/err.h>
 #include <linux/mutex.h>
 #include <asm/io.h>
 
+/* ISA device, if found */
+static struct platform_device *pdev;
+
 /* Addresses to scan */
 static unsigned short normal_i2c[] = { 0x20, 0x21, 0x22, 0x23, 0x24,
                                         0x25, 0x26, 0x27, 0x28, 0x29,
@@ -121,12 +126,8 @@ static inline int TEMP_FROM_REG(s8 val)
    a bit - except if there could be more than one SMBus. Groan. No solution
    for this yet. */
 
-/* This module may seem overly long and complicated. In fact, it is not so
-   bad. Quite a lot of bookkeeping is done. A real driver can often cut
-   some corners. */
-
-/* For each registered chip, we need to keep some data in memory.
-   The structure is dynamically allocated. */
+/* For ISA chips, we abuse the i2c_client addr and name fields. We also use
+   the driver field to differentiate between I2C and ISA chips. */
 struct lm78_data {
         struct i2c_client client;
         struct class_device *class_dev;
@@ -152,10 +153,12 @@ struct lm78_data {
 
 
 static int lm78_attach_adapter(struct i2c_adapter *adapter);
-static int lm78_isa_attach_adapter(struct i2c_adapter *adapter);
 static int lm78_detect(struct i2c_adapter *adapter, int address, int kind);
 static int lm78_detach_client(struct i2c_client *client);
 
+static int __devinit lm78_isa_probe(struct platform_device *pdev);
+static int __devexit lm78_isa_remove(struct platform_device *pdev);
+
 static int lm78_read_value(struct i2c_client *client, u8 reg);
 static int lm78_write_value(struct i2c_client *client, u8 reg, u8 value);
 static struct lm78_data *lm78_update_device(struct device *dev);
@@ -171,13 +174,13 @@ static struct i2c_driver lm78_driver = {
         .detach_client  = lm78_detach_client,
 };
 
-static struct i2c_driver lm78_isa_driver = {
+static struct platform_driver lm78_isa_driver = {
         .driver = {
                 .owner  = THIS_MODULE,
-                .name   = "lm78-isa",
+                .name   = "lm78",
         },
-        .attach_adapter = lm78_isa_attach_adapter,
-        .detach_client  = lm78_detach_client,
+        .probe          = lm78_isa_probe,
+        .remove         = lm78_isa_remove,
 };
 
 
@@ -203,8 +206,8 @@ static ssize_t show_in_max(struct device *dev, char *buf, int nr)
 static ssize_t set_in_min(struct device *dev, const char *buf,
                 size_t count, int nr)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lm78_data *data = i2c_get_clientdata(client);
+        struct lm78_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = &data->client;
         unsigned long val = simple_strtoul(buf, NULL, 10);
 
         mutex_lock(&data->update_lock);
@@ -217,8 +220,8 @@ static ssize_t set_in_min(struct device *dev, const char *buf,
 static ssize_t set_in_max(struct device *dev, const char *buf,
                 size_t count, int nr)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lm78_data *data = i2c_get_clientdata(client);
+        struct lm78_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = &data->client;
         unsigned long val = simple_strtoul(buf, NULL, 10);
 
         mutex_lock(&data->update_lock);
@@ -284,8 +287,8 @@ static ssize_t show_temp_over(struct device *dev, struct device_attribute *attr,
 
 static ssize_t set_temp_over(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lm78_data *data = i2c_get_clientdata(client);
+        struct lm78_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = &data->client;
         long val = simple_strtol(buf, NULL, 10);
 
         mutex_lock(&data->update_lock);
@@ -303,8 +306,8 @@ static ssize_t show_temp_hyst(struct device *dev, struct device_attribute *attr,
 
 static ssize_t set_temp_hyst(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lm78_data *data = i2c_get_clientdata(client);
+        struct lm78_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = &data->client;
         long val = simple_strtol(buf, NULL, 10);
 
         mutex_lock(&data->update_lock);
@@ -338,8 +341,8 @@ static ssize_t show_fan_min(struct device *dev, char *buf, int nr)
 static ssize_t set_fan_min(struct device *dev, const char *buf,
                 size_t count, int nr)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lm78_data *data = i2c_get_clientdata(client);
+        struct lm78_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = &data->client;
         unsigned long val = simple_strtoul(buf, NULL, 10);
 
         mutex_lock(&data->update_lock);
@@ -362,8 +365,8 @@ static ssize_t show_fan_div(struct device *dev, char *buf, int nr)
 static ssize_t set_fan_div(struct device *dev, const char *buf,
         size_t count, int nr)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lm78_data *data = i2c_get_clientdata(client);
+        struct lm78_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = &data->client;
         unsigned long val = simple_strtoul(buf, NULL, 10);
         unsigned long min;
         u8 reg;
@@ -378,7 +381,7 @@ static ssize_t set_fan_div(struct device *dev, const char *buf,
         case 4: data->fan_div[nr] = 2; break;
         case 8: data->fan_div[nr] = 3; break;
         default:
-                dev_err(&client->dev, "fan_div value %ld not "
+                dev_err(dev, "fan_div value %ld not "
                         "supported. Choose one of 1, 2, 4 or 8!\n", val);
                 mutex_unlock(&data->update_lock);
                 return -EINVAL;
@@ -475,11 +478,6 @@ static int lm78_attach_adapter(struct i2c_adapter *adapter)
         return i2c_probe(adapter, &addr_data, lm78_detect);
 }
 
-static int lm78_isa_attach_adapter(struct i2c_adapter *adapter)
-{
-        return lm78_detect(adapter, isa_address, -1);
-}
-
 static struct attribute *lm78_attributes[] = {
         &dev_attr_in0_input.attr,
         &dev_attr_in0_min.attr,
@@ -524,6 +522,17 @@ static const struct attribute_group lm78_group = {
         .attrs = lm78_attributes,
 };
 
+/* I2C devices get this name attribute automatically, but for ISA devices
+   we must create it by ourselves. */
+static ssize_t show_name(struct device *dev, struct device_attribute
+                         *devattr, char *buf)
+{
+        struct lm78_data *data = dev_get_drvdata(dev);
+
+        return sprintf(buf, "%s\n", data->client.name);
+}
+static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
+
 /* This function is called by i2c_probe */
 static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
 {
@@ -531,54 +540,10 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
         struct i2c_client *new_client;
         struct lm78_data *data;
         const char *client_name = "";
-        int is_isa = i2c_is_isa_adapter(adapter);
 
-        if (!is_isa &&
-            !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
+        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
                 err = -ENODEV;
-                goto ERROR0;
-        }
-
-        /* Reserve the ISA region */
-        if (is_isa)
-                if (!request_region(address, LM78_EXTENT,
-                                    lm78_isa_driver.driver.name)) {
-                        err = -EBUSY;
-                        goto ERROR0;
-                }
-
-        /* Probe whether there is anything available on this address. Already
-           done for SMBus clients */
-        if (kind < 0) {
-                if (is_isa) {
-
-#define REALLY_SLOW_IO
-                        /* We need the timeouts for at least some LM78-like
-                           chips. But only if we read 'undefined' registers. */
-                        i = inb_p(address + 1);
-                        if (inb_p(address + 2) != i) {
-                                err = -ENODEV;
-                                goto ERROR1;
-                        }
-                        if (inb_p(address + 3) != i) {
-                                err = -ENODEV;
-                                goto ERROR1;
-                        }
-                        if (inb_p(address + 7) != i) {
-                                err = -ENODEV;
-                                goto ERROR1;
-                        }
-#undef REALLY_SLOW_IO
-
-                        /* Let's just hope nothing breaks here */
-                        i = inb_p(address + 5) & 0x7f;
-                        outb_p(~i & 0x7f, address + 5);
-                        if ((inb_p(address + 5) & 0x7f) != (~i & 0x7f)) {
-                                outb_p(i, address + 5);
-                                err = -ENODEV;
-                                goto ERROR1;
-                        }
-                }
+                goto ERROR1;
         }
 
         /* OK. For now, we presume we have a valid client. We now create the
@@ -591,13 +556,10 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
         }
 
         new_client = &data->client;
-        if (is_isa)
-                mutex_init(&data->lock);
         i2c_set_clientdata(new_client, data);
         new_client->addr = address;
         new_client->adapter = adapter;
-        new_client->driver = is_isa ? &lm78_isa_driver : &lm78_driver;
-        new_client->flags = 0;
+        new_client->driver = &lm78_driver;
 
         /* Now, we do the remaining detection. */
         if (kind < 0) {
@@ -605,8 +567,8 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
                         err = -ENODEV;
                         goto ERROR2;
                 }
-                if (!is_isa && (lm78_read_value(
-                                new_client, LM78_REG_I2C_ADDR) != address)) {
+                if (lm78_read_value(new_client, LM78_REG_I2C_ADDR) !=
+                    address) {
                         err = -ENODEV;
                         goto ERROR2;
                 }
@@ -641,9 +603,6 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
         strlcpy(new_client->name, client_name, I2C_NAME_SIZE);
         data->type = kind;
 
-        data->valid = 0;
-        mutex_init(&data->update_lock);
-
         /* Tell the I2C layer a new client has arrived */
         if ((err = i2c_attach_client(new_client)))
                 goto ERROR2;
@@ -651,12 +610,6 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
         /* Initialize the LM78 chip */
         lm78_init_client(new_client);
 
-        /* A few vars need to be filled upon startup */
-        for (i = 0; i < 3; i++) {
-                data->fan_min[i] = lm78_read_value(new_client,
-                                        LM78_REG_FAN_MIN(i));
-        }
-
         /* Register sysfs hooks */
         if ((err = sysfs_create_group(&new_client->dev.kobj, &lm78_group)))
                 goto ERROR3;
@@ -676,9 +629,6 @@ ERROR3:
 ERROR2:
         kfree(data);
 ERROR1:
-        if (is_isa)
-                release_region(address, LM78_EXTENT);
-ERROR0:
         return err;
 }
 
@@ -693,9 +643,77 @@ static int lm78_detach_client(struct i2c_client *client)
         if ((err = i2c_detach_client(client)))
                 return err;
 
-        if(i2c_is_isa_client(client))
-                release_region(client->addr, LM78_EXTENT);
+        kfree(data);
+
+        return 0;
+}
+
+static int __devinit lm78_isa_probe(struct platform_device *pdev)
+{
+        int err;
+        struct lm78_data *data;
+        struct resource *res;
+        const char *name;
+
+        /* Reserve the ISA region */
+        res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+        if (!request_region(res->start, LM78_EXTENT, "lm78")) {
+                err = -EBUSY;
+                goto exit;
+        }
+
+        if (!(data = kzalloc(sizeof(struct lm78_data), GFP_KERNEL))) {
+                err = -ENOMEM;
+                goto exit_release_region;
+        }
+        mutex_init(&data->lock);
+        data->client.addr = res->start;
+        i2c_set_clientdata(&data->client, data);
+        platform_set_drvdata(pdev, data);
+
+        if (lm78_read_value(&data->client, LM78_REG_CHIPID) & 0x80) {
+                data->type = lm79;
+                name = "lm79";
+        } else {
+                data->type = lm78;
+                name = "lm78";
+        }
+        strlcpy(data->client.name, name, I2C_NAME_SIZE);
+
+        /* Initialize the LM78 chip */
+        lm78_init_client(&data->client);
+
+        /* Register sysfs hooks */
+        if ((err = sysfs_create_group(&pdev->dev.kobj, &lm78_group))
+         || (err = device_create_file(&pdev->dev, &dev_attr_name)))
+                goto exit_remove_files;
+
+        data->class_dev = hwmon_device_register(&pdev->dev);
+        if (IS_ERR(data->class_dev)) {
+                err = PTR_ERR(data->class_dev);
+                goto exit_remove_files;
+        }
+
+        return 0;
+
+ exit_remove_files:
+        sysfs_remove_group(&pdev->dev.kobj, &lm78_group);
+        device_remove_file(&pdev->dev, &dev_attr_name);
+        kfree(data);
+ exit_release_region:
+        release_region(res->start, LM78_EXTENT);
+ exit:
+        return err;
+}
+
+static int __devexit lm78_isa_remove(struct platform_device *pdev)
+{
+        struct lm78_data *data = platform_get_drvdata(pdev);
 
+        hwmon_device_unregister(data->class_dev);
+        sysfs_remove_group(&pdev->dev.kobj, &lm78_group);
+        device_remove_file(&pdev->dev, &dev_attr_name);
+        release_region(data->client.addr, LM78_EXTENT);
         kfree(data);
 
         return 0;
@@ -709,7 +727,7 @@ static int lm78_detach_client(struct i2c_client *client)
 static int lm78_read_value(struct i2c_client *client, u8 reg)
 {
         int res;
-        if (i2c_is_isa_client(client)) {
+        if (!client->driver) { /* ISA device */
                 struct lm78_data *data = i2c_get_clientdata(client);
                 mutex_lock(&data->lock);
                 outb_p(reg, client->addr + LM78_ADDR_REG_OFFSET);
@@ -729,7 +747,7 @@ static int lm78_read_value(struct i2c_client *client, u8 reg)
    nowhere else be necessary! */
 static int lm78_write_value(struct i2c_client *client, u8 reg, u8 value)
 {
-        if (i2c_is_isa_client(client)) {
+        if (!client->driver) { /* ISA device */
                 struct lm78_data *data = i2c_get_clientdata(client);
                 mutex_lock(&data->lock);
                 outb_p(reg, client->addr + LM78_ADDR_REG_OFFSET);
@@ -742,18 +760,29 @@ static int lm78_write_value(struct i2c_client *client, u8 reg, u8 value)
 
 static void lm78_init_client(struct i2c_client *client)
 {
-        u8 config = lm78_read_value(client, LM78_REG_CONFIG);
+        struct lm78_data *data = i2c_get_clientdata(client);
+        u8 config;
+        int i;
 
         /* Start monitoring */
-        if (!(config & 0x01))
+        config = lm78_read_value(client, LM78_REG_CONFIG);
+        if ((config & 0x09) != 0x01)
                 lm78_write_value(client, LM78_REG_CONFIG,
                                  (config & 0xf7) | 0x01);
+
+        /* A few vars need to be filled upon startup */
+        for (i = 0; i < 3; i++) {
+                data->fan_min[i] = lm78_read_value(client,
+                                        LM78_REG_FAN_MIN(i));
+        }
+
+        mutex_init(&data->update_lock);
 }
 
 static struct lm78_data *lm78_update_device(struct device *dev)
 {
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lm78_data *data = i2c_get_clientdata(client);
+        struct lm78_data *data = dev_get_drvdata(dev);
+        struct i2c_client *client = &data->client;
         int i;
 
         mutex_lock(&data->update_lock);
@@ -761,7 +790,7 @@ static struct lm78_data *lm78_update_device(struct device *dev)
         if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
             || !data->valid) {
 
-                dev_dbg(&client->dev, "Starting lm78 update\n");
+                dev_dbg(dev, "Starting lm78 update\n");
 
                 for (i = 0; i <= 6; i++) {
                         data->in[i] =
@@ -805,26 +834,154 @@ static struct lm78_data *lm78_update_device(struct device *dev)
         return data;
 }
 
+/* return 1 if a supported chip is found, 0 otherwise */
+static int __init lm78_isa_found(unsigned short address)
+{
+        int val, save, found = 0;
+
+        if (!request_region(address, LM78_EXTENT, "lm78"))
+                return 0;
+
+#define REALLY_SLOW_IO
+        /* We need the timeouts for at least some LM78-like
+           chips. But only if we read 'undefined' registers. */
+        val = inb_p(address + 1);
+        if (inb_p(address + 2) != val
+         || inb_p(address + 3) != val
+         || inb_p(address + 7) != val)
+                goto release;
+#undef REALLY_SLOW_IO
+
+        /* We should be able to change the 7 LSB of the address port. The
+           MSB (busy flag) should be clear initially, set after the write. */
+        save = inb_p(address + LM78_ADDR_REG_OFFSET);
+        if (save & 0x80)
+                goto release;
+        val = ~save & 0x7f;
+        outb_p(val, address + LM78_ADDR_REG_OFFSET);
+        if (inb_p(address + LM78_ADDR_REG_OFFSET) != (val | 0x80)) {
+                outb_p(save, address + LM78_ADDR_REG_OFFSET);
+                goto release;
+        }
+
+        /* We found a device, now see if it could be an LM78 */
+        outb_p(LM78_REG_CONFIG, address + LM78_ADDR_REG_OFFSET);
+        val = inb_p(address + LM78_DATA_REG_OFFSET);
+        if (val & 0x80)
+                goto release;
+        outb_p(LM78_REG_I2C_ADDR, address + LM78_ADDR_REG_OFFSET);
+        val = inb_p(address + LM78_DATA_REG_OFFSET);
+        if (val < 0x03 || val > 0x77)   /* Not a valid I2C address */
+                goto release;
+
+        /* The busy flag should be clear again */
+        if (inb_p(address + LM78_ADDR_REG_OFFSET) & 0x80)
+                goto release;
+
+        /* Explicitly prevent the misdetection of Winbond chips */
+        outb_p(0x4f, address + LM78_ADDR_REG_OFFSET);
+        val = inb_p(address + LM78_DATA_REG_OFFSET);
+        if (val == 0xa3 || val == 0x5c)
+                goto release;
+
+        /* Explicitly prevent the misdetection of ITE chips */
+        outb_p(0x58, address + LM78_ADDR_REG_OFFSET);
+        val = inb_p(address + LM78_DATA_REG_OFFSET);
+        if (val == 0x90)
+                goto release;
+
+        /* Determine the chip type */
+        outb_p(LM78_REG_CHIPID, address + LM78_ADDR_REG_OFFSET);
+        val = inb_p(address + LM78_DATA_REG_OFFSET);
+        if (val == 0x00                 /* LM78 */
+         || val == 0x40                 /* LM78-J */
+         || (val & 0xfe) == 0xc0)       /* LM79 */
+                found = 1;
+
+        if (found)
+                pr_info("lm78: Found an %s chip at %#x\n",
+                        val & 0x80 ? "LM79" : "LM78", (int)address);
+
+ release:
+        release_region(address, LM78_EXTENT);
+        return found;
+}
+
+static int __init lm78_isa_device_add(unsigned short address)
+{
+        struct resource res = {
+                .start  = address,
+                .end    = address + LM78_EXTENT,
+                .name   = "lm78",
+                .flags  = IORESOURCE_IO,
+        };
+        int err;
+
+        pdev = platform_device_alloc("lm78", address);
+        if (!pdev) {
+                err = -ENOMEM;
+                printk(KERN_ERR "lm78: Device allocation failed\n");
+                goto exit;
+        }
+
+        err = platform_device_add_resources(pdev, &res, 1);
+        if (err) {
+                printk(KERN_ERR "lm78: Device resource addition failed "
+                       "(%d)\n", err);
+                goto exit_device_put;
+        }
+
+        err = platform_device_add(pdev);
+        if (err) {
+                printk(KERN_ERR "lm78: Device addition failed (%d)\n",
+                       err);
+                goto exit_device_put;
+        }
+
+        return 0;
+
+ exit_device_put:
+        platform_device_put(pdev);
+ exit:
+        pdev = NULL;
+        return err;
+}
+
 static int __init sm_lm78_init(void)
 {
         int res;
 
         res = i2c_add_driver(&lm78_driver);
         if (res)
-                return res;
+                goto exit;
+
+        if (lm78_isa_found(isa_address)) {
+                res = platform_driver_register(&lm78_isa_driver);
+                if (res)
+                        goto exit_unreg_i2c_driver;
 
-        /* Don't exit if this one fails, we still want the I2C variants
-           to work! */
-        if (i2c_isa_add_driver(&lm78_isa_driver))
-                isa_address = 0;
+                /* Sets global pdev as a side effect */
+                res = lm78_isa_device_add(isa_address);
+                if (res)
+                        goto exit_unreg_isa_driver;
+        }
 
         return 0;
+
+ exit_unreg_isa_driver:
+        platform_driver_unregister(&lm78_isa_driver);
+ exit_unreg_i2c_driver:
+        i2c_del_driver(&lm78_driver);
+ exit:
+        return res;
 }
 
 static void __exit sm_lm78_exit(void)
 {
-        if (isa_address)
-                i2c_isa_del_driver(&lm78_isa_driver);
+        if (pdev) {
+                platform_device_unregister(pdev);
+                platform_driver_unregister(&lm78_isa_driver);
+        }
         i2c_del_driver(&lm78_driver);
 }