1 files changed, 48 insertions, 45 deletions

diff --git a/drivers/w1/masters/ds2482.c b/drivers/w1/masters/ds2482.c
index df52cb355f7..e033491fe30 100644
--- a/drivers/w1/masters/ds2482.c
+++ b/drivers/w1/masters/ds2482.c
@@ -24,19 +24,6 @@
 #include "../w1_int.h"
 
 /**
- * Address is selected using 2 pins, resulting in 4 possible addresses.
- *  0x18, 0x19, 0x1a, 0x1b
- * However, the chip cannot be detected without doing an i2c write,
- * so use the force module parameter.
- */
-static const unsigned short normal_i2c[] = { I2C_CLIENT_END };
-
-/**
- * Insmod parameters
- */
-I2C_CLIENT_INSMOD_1(ds2482);
-
-/**
  * The DS2482 registers - there are 3 registers that are addressed by a read
  * pointer. The read pointer is set by the last command executed.
  *
@@ -64,10 +51,10 @@ I2C_CLIENT_INSMOD_1(ds2482);
  * The top 4 bits always read 0.
  * To write, the top nibble must be the 1's compl. of the low nibble.
  */
-#define DS2482_REG_CFG_1WS		0x08
-#define DS2482_REG_CFG_SPU		0x04
-#define DS2482_REG_CFG_PPM		0x02
-#define DS2482_REG_CFG_APU		0x01
+#define DS2482_REG_CFG_1WS		0x08	/* 1-wire speed */
+#define DS2482_REG_CFG_SPU		0x04	/* strong pull-up */
+#define DS2482_REG_CFG_PPM		0x02	/* presence pulse masking */
+#define DS2482_REG_CFG_APU		0x01	/* active pull-up */
 
 
 /**
@@ -96,8 +83,6 @@ static const u8 ds2482_chan_rd[8] =
 
 static int ds2482_probe(struct i2c_client *client,
 			const struct i2c_device_id *id);
-static int ds2482_detect(struct i2c_client *client, int kind,
-			 struct i2c_board_info *info);
 static int ds2482_remove(struct i2c_client *client);
 
 
@@ -117,8 +102,6 @@ static struct i2c_driver ds2482_driver = {
 	.probe		= ds2482_probe,
 	.remove		= ds2482_remove,
 	.id_table	= ds2482_id,
-	.detect		= ds2482_detect,
-	.address_data	= &addr_data,
 };
 
 /*
@@ -149,6 +132,17 @@ struct ds2482_data {
 
 
 /**
+ * Helper to calculate values for configuration register
+ * @param conf the raw config value
+ * @return the value w/ complements that can be written to register
+ */
+static inline u8 ds2482_calculate_config(u8 conf)
+{
+	return conf | ((~conf & 0x0f) << 4);
+}
+
+
+/**
  * Sets the read pointer.
  * @param pdev		The ds2482 client pointer
  * @param read_ptr	see DS2482_PTR_CODE_xxx above
@@ -231,7 +225,7 @@ static int ds2482_wait_1wire_idle(struct ds2482_data *pdev)
 			 (++retries < DS2482_WAIT_IDLE_TIMEOUT));
 	}
 
-	if (retries > DS2482_WAIT_IDLE_TIMEOUT)
+	if (retries >= DS2482_WAIT_IDLE_TIMEOUT)
 		printk(KERN_ERR "%s: timeout on channel %d\n",
 		       __func__, pdev->channel);
 
@@ -416,7 +410,7 @@ static u8 ds2482_w1_reset_bus(void *data)
 		/* If the chip did reset since detect, re-config it */
 		if (err & DS2482_REG_STS_RST)
 			ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,
-					     0xF0);
+					     ds2482_calculate_config(0x00));
 	}
 
 	mutex_unlock(&pdev->access_lock);
@@ -424,20 +418,33 @@ static u8 ds2482_w1_reset_bus(void *data)
 	return retval;
 }
 
-
-static int ds2482_detect(struct i2c_client *client, int kind,
-			 struct i2c_board_info *info)
+static u8 ds2482_w1_set_pullup(void *data, int delay)
 {
-	if (!i2c_check_functionality(client->adapter,
-				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
-				     I2C_FUNC_SMBUS_BYTE))
-		return -ENODEV;
+	struct ds2482_w1_chan *pchan = data;
+	struct ds2482_data    *pdev = pchan->pdev;
+	u8 retval = 1;
 
-	strlcpy(info->type, "ds2482", I2C_NAME_SIZE);
+	/* if delay is non-zero activate the pullup,
+	 * the strong pullup will be automatically deactivated
+	 * by the master, so do not explicitly deactive it
+	 */
+	if (delay) {
+		/* both waits are crucial, otherwise devices might not be
+		 * powered long enough, causing e.g. a w1_therm sensor to
+		 * provide wrong conversion results
+		 */
+		ds2482_wait_1wire_idle(pdev);
+		/* note: it seems like both SPU and APU have to be set! */
+		retval = ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,
+			ds2482_calculate_config(DS2482_REG_CFG_SPU |
+						DS2482_REG_CFG_APU));
+		ds2482_wait_1wire_idle(pdev);
+	}
 
-	return 0;
+	return retval;
 }
 
+
 static int ds2482_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
@@ -446,6 +453,11 @@ static int ds2482_probe(struct i2c_client *client,
 	int temp1;
 	int idx;
 
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
+				     I2C_FUNC_SMBUS_BYTE))
+		return -ENODEV;
+
 	if (!(data = kzalloc(sizeof(struct ds2482_data), GFP_KERNEL))) {
 		err = -ENOMEM;
 		goto exit;
@@ -477,7 +489,8 @@ static int ds2482_probe(struct i2c_client *client,
 		data->w1_count = 8;
 
 	/* Set all config items to 0 (off) */
-	ds2482_send_cmd_data(data, DS2482_CMD_WRITE_CONFIG, 0xF0);
+	ds2482_send_cmd_data(data, DS2482_CMD_WRITE_CONFIG,
+		ds2482_calculate_config(0x00));
 
 	mutex_init(&data->access_lock);
 
@@ -493,6 +506,7 @@ static int ds2482_probe(struct i2c_client *client,
 		data->w1_ch[idx].w1_bm.touch_bit  = ds2482_w1_touch_bit;
 		data->w1_ch[idx].w1_bm.triplet    = ds2482_w1_triplet;
 		data->w1_ch[idx].w1_bm.reset_bus  = ds2482_w1_reset_bus;
+		data->w1_ch[idx].w1_bm.set_pullup = ds2482_w1_set_pullup;
 
 		err = w1_add_master_device(&data->w1_ch[idx].w1_bm);
 		if (err) {
@@ -530,19 +544,8 @@ static int ds2482_remove(struct i2c_client *client)
 	return 0;
 }
 
-static int __init sensors_ds2482_init(void)
-{
-	return i2c_add_driver(&ds2482_driver);
-}
-
-static void __exit sensors_ds2482_exit(void)
-{
-	i2c_del_driver(&ds2482_driver);
-}
+module_i2c_driver(ds2482_driver);
 
 MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
 MODULE_DESCRIPTION("DS2482 driver");
 MODULE_LICENSE("GPL");
-
-module_init(sensors_ds2482_init);
-module_exit(sensors_ds2482_exit);