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Diffstat (limited to 'drivers/w1/masters/ds2482.c')
-rw-r--r--drivers/w1/masters/ds2482.c206
1 files changed, 108 insertions, 98 deletions
diff --git a/drivers/w1/masters/ds2482.c b/drivers/w1/masters/ds2482.c
index e033491fe308..e2a568c9a43a 100644
--- a/drivers/w1/masters/ds2482.c
+++ b/drivers/w1/masters/ds2482.c
@@ -1,4 +1,5 @@
-/**
+// SPDX-License-Identifier: GPL-2.0-only
+/*
* ds2482.c - provides i2c to w1-master bridge(s)
* Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
*
@@ -6,11 +7,7 @@
* It is a I2C to 1-wire bridge.
* There are two variations: -100 and -800, which have 1 or 8 1-wire ports.
* The complete datasheet can be obtained from MAXIM's website at:
- * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/4382
- *
- * 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; version 2 of the License.
+ * https://www.analog.com/en/products/ds2482-100.html
*/
#include <linux/module.h>
@@ -18,12 +15,31 @@
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/delay.h>
-#include <asm/delay.h>
+#include <linux/regulator/consumer.h>
-#include "../w1.h"
-#include "../w1_int.h"
+#include <linux/w1.h>
-/**
+/*
+ * Allow the active pullup to be disabled, default is enabled.
+ *
+ * Note from the DS2482 datasheet:
+ * The APU bit controls whether an active pullup (controlled slew-rate
+ * transistor) or a passive pullup (Rwpu resistor) will be used to drive
+ * a 1-Wire line from low to high. When APU = 0, active pullup is disabled
+ * (resistor mode). Active Pullup should always be selected unless there is
+ * only a single slave on the 1-Wire line.
+ */
+static int ds2482_active_pullup = 1;
+module_param_named(active_pullup, ds2482_active_pullup, int, 0644);
+MODULE_PARM_DESC(active_pullup, "Active pullup (apply to all buses): " \
+ "0-disable, 1-enable (default)");
+
+/* extra configurations - e.g. 1WS */
+static int extra_config;
+module_param(extra_config, int, 0644);
+MODULE_PARM_DESC(extra_config, "Extra Configuration settings 1=APU,2=PPM,3=SPU,8=1WS");
+
+/*
* The DS2482 registers - there are 3 registers that are addressed by a read
* pointer. The read pointer is set by the last command executed.
*
@@ -46,7 +62,7 @@
#define DS2482_PTR_CODE_CHANNEL 0xD2 /* DS2482-800 only */
#define DS2482_PTR_CODE_CONFIG 0xC3
-/**
+/*
* Configure Register bit definitions
* The top 4 bits always read 0.
* To write, the top nibble must be the 1's compl. of the low nibble.
@@ -57,18 +73,16 @@
#define DS2482_REG_CFG_APU 0x01 /* active pull-up */
-/**
+/*
* Write and verify codes for the CHANNEL_SELECT command (DS2482-800 only).
* To set the channel, write the value at the index of the channel.
* Read and compare against the corresponding value to verify the change.
*/
-static const u8 ds2482_chan_wr[8] =
- { 0xF0, 0xE1, 0xD2, 0xC3, 0xB4, 0xA5, 0x96, 0x87 };
-static const u8 ds2482_chan_rd[8] =
- { 0xB8, 0xB1, 0xAA, 0xA3, 0x9C, 0x95, 0x8E, 0x87 };
+static const u8 ds2482_chan_wr[8] = { 0xF0, 0xE1, 0xD2, 0xC3, 0xB4, 0xA5, 0x96, 0x87 };
+static const u8 ds2482_chan_rd[8] = { 0xB8, 0xB1, 0xAA, 0xA3, 0x9C, 0x95, 0x8E, 0x87 };
-/**
+/*
* Status Register bit definitions (read only)
*/
#define DS2482_REG_STS_DIR 0x80
@@ -80,30 +94,6 @@ static const u8 ds2482_chan_rd[8] =
#define DS2482_REG_STS_PPD 0x02
#define DS2482_REG_STS_1WB 0x01
-
-static int ds2482_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-static int ds2482_remove(struct i2c_client *client);
-
-
-/**
- * Driver data (common to all clients)
- */
-static const struct i2c_device_id ds2482_id[] = {
- { "ds2482", 0 },
- { }
-};
-
-static struct i2c_driver ds2482_driver = {
- .driver = {
- .owner = THIS_MODULE,
- .name = "ds2482",
- },
- .probe = ds2482_probe,
- .remove = ds2482_remove,
- .id_table = ds2482_id,
-};
-
/*
* Client data (each client gets its own)
*/
@@ -132,21 +122,26 @@ 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
+ * ds2482_calculate_config - Helper to calculate values for configuration register
+ * @conf: the raw config value
+ * Return: the value w/ complements that can be written to register
*/
static inline u8 ds2482_calculate_config(u8 conf)
{
+ conf |= extra_config;
+
+ if (ds2482_active_pullup)
+ conf |= DS2482_REG_CFG_APU;
+
return conf | ((~conf & 0x0f) << 4);
}
/**
- * Sets the read pointer.
- * @param pdev The ds2482 client pointer
- * @param read_ptr see DS2482_PTR_CODE_xxx above
- * @return -1 on failure, 0 on success
+ * ds2482_select_register - Sets the read pointer.
+ * @pdev: The ds2482 client pointer
+ * @read_ptr: see DS2482_PTR_CODE_xxx above
+ * Return: -1 on failure, 0 on success
*/
static inline int ds2482_select_register(struct ds2482_data *pdev, u8 read_ptr)
{
@@ -162,12 +157,12 @@ static inline int ds2482_select_register(struct ds2482_data *pdev, u8 read_ptr)
}
/**
- * Sends a command without a parameter
- * @param pdev The ds2482 client pointer
- * @param cmd DS2482_CMD_RESET,
+ * ds2482_send_cmd - Sends a command without a parameter
+ * @pdev: The ds2482 client pointer
+ * @cmd: DS2482_CMD_RESET,
* DS2482_CMD_1WIRE_RESET,
* DS2482_CMD_1WIRE_READ_BYTE
- * @return -1 on failure, 0 on success
+ * Return: -1 on failure, 0 on success
*/
static inline int ds2482_send_cmd(struct ds2482_data *pdev, u8 cmd)
{
@@ -179,14 +174,14 @@ static inline int ds2482_send_cmd(struct ds2482_data *pdev, u8 cmd)
}
/**
- * Sends a command with a parameter
- * @param pdev The ds2482 client pointer
- * @param cmd DS2482_CMD_WRITE_CONFIG,
+ * ds2482_send_cmd_data - Sends a command with a parameter
+ * @pdev: The ds2482 client pointer
+ * @cmd: DS2482_CMD_WRITE_CONFIG,
* DS2482_CMD_1WIRE_SINGLE_BIT,
* DS2482_CMD_1WIRE_WRITE_BYTE,
* DS2482_CMD_1WIRE_TRIPLET
- * @param byte The data to send
- * @return -1 on failure, 0 on success
+ * @byte: The data to send
+ * Return: -1 on failure, 0 on success
*/
static inline int ds2482_send_cmd_data(struct ds2482_data *pdev,
u8 cmd, u8 byte)
@@ -208,10 +203,10 @@ static inline int ds2482_send_cmd_data(struct ds2482_data *pdev,
#define DS2482_WAIT_IDLE_TIMEOUT 100
/**
- * Waits until the 1-wire interface is idle (not busy)
+ * ds2482_wait_1wire_idle - Waits until the 1-wire interface is idle (not busy)
*
- * @param pdev Pointer to the device structure
- * @return the last value read from status or -1 (failure)
+ * @pdev: Pointer to the device structure
+ * Return: the last value read from status or -1 (failure)
*/
static int ds2482_wait_1wire_idle(struct ds2482_data *pdev)
{
@@ -226,19 +221,19 @@ static int ds2482_wait_1wire_idle(struct ds2482_data *pdev)
}
if (retries >= DS2482_WAIT_IDLE_TIMEOUT)
- printk(KERN_ERR "%s: timeout on channel %d\n",
+ pr_err("%s: timeout on channel %d\n",
__func__, pdev->channel);
return temp;
}
/**
- * Selects a w1 channel.
+ * ds2482_set_channel - Selects a w1 channel.
* The 1-wire interface must be idle before calling this function.
*
- * @param pdev The ds2482 client pointer
- * @param channel 0-7
- * @return -1 (failure) or 0 (success)
+ * @pdev: The ds2482 client pointer
+ * @channel: 0-7
+ * Return: -1 (failure) or 0 (success)
*/
static int ds2482_set_channel(struct ds2482_data *pdev, u8 channel)
{
@@ -257,11 +252,11 @@ static int ds2482_set_channel(struct ds2482_data *pdev, u8 channel)
/**
- * Performs the touch-bit function, which writes a 0 or 1 and reads the level.
+ * ds2482_w1_touch_bit - Performs the touch-bit function, which writes a 0 or 1 and reads the level.
*
- * @param data The ds2482 channel pointer
- * @param bit The level to write: 0 or non-zero
- * @return The level read: 0 or 1
+ * @data: The ds2482 channel pointer
+ * @bit: The level to write: 0 or non-zero
+ * Return: The level read: 0 or 1
*/
static u8 ds2482_w1_touch_bit(void *data, u8 bit)
{
@@ -287,13 +282,13 @@ static u8 ds2482_w1_touch_bit(void *data, u8 bit)
}
/**
- * Performs the triplet function, which reads two bits and writes a bit.
+ * ds2482_w1_triplet - Performs the triplet function, which reads two bits and writes a bit.
* The bit written is determined by the two reads:
* 00 => dbit, 01 => 0, 10 => 1
*
- * @param data The ds2482 channel pointer
- * @param dbit The direction to choose if both branches are valid
- * @return b0=read1 b1=read2 b3=bit written
+ * @data: The ds2482 channel pointer
+ * @dbit: The direction to choose if both branches are valid
+ * Return: b0=read1 b1=read2 b3=bit written
*/
static u8 ds2482_w1_triplet(void *data, u8 dbit)
{
@@ -320,10 +315,10 @@ static u8 ds2482_w1_triplet(void *data, u8 dbit)
}
/**
- * Performs the write byte function.
+ * ds2482_w1_write_byte - Performs the write byte function.
*
- * @param data The ds2482 channel pointer
- * @param byte The value to write
+ * @data: The ds2482 channel pointer
+ * @byte: The value to write
*/
static void ds2482_w1_write_byte(void *data, u8 byte)
{
@@ -344,10 +339,10 @@ static void ds2482_w1_write_byte(void *data, u8 byte)
}
/**
- * Performs the read byte function.
+ * ds2482_w1_read_byte - Performs the read byte function.
*
- * @param data The ds2482 channel pointer
- * @return The value read
+ * @data: The ds2482 channel pointer
+ * Return: The value read
*/
static u8 ds2482_w1_read_byte(void *data)
{
@@ -381,10 +376,10 @@ static u8 ds2482_w1_read_byte(void *data)
/**
- * Sends a reset on the 1-wire interface
+ * ds2482_w1_reset_bus - Sends a reset on the 1-wire interface
*
- * @param data The ds2482 channel pointer
- * @return 0=Device present, 1=No device present or error
+ * @data: The ds2482 channel pointer
+ * Return: 0=Device present, 1=No device present or error
*/
static u8 ds2482_w1_reset_bus(void *data)
{
@@ -445,23 +440,26 @@ static u8 ds2482_w1_set_pullup(void *data, int delay)
}
-static int ds2482_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+static int ds2482_probe(struct i2c_client *client)
{
struct ds2482_data *data;
int err = -ENODEV;
int temp1;
int idx;
+ int ret;
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;
- }
+ data = devm_kzalloc(&client->dev, sizeof(struct ds2482_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ret = devm_regulator_get_enable(&client->dev, "vcc");
+ if (ret)
+ return dev_err_probe(&client->dev, ret, "Failed to enable regulator\n");
data->client = client;
i2c_set_clientdata(client, data);
@@ -469,7 +467,7 @@ static int ds2482_probe(struct i2c_client *client,
/* Reset the device (sets the read_ptr to status) */
if (ds2482_send_cmd(data, DS2482_CMD_RESET) < 0) {
dev_warn(&client->dev, "DS2482 reset failed.\n");
- goto exit_free;
+ return err;
}
/* Sleep at least 525ns to allow the reset to complete */
@@ -480,7 +478,7 @@ static int ds2482_probe(struct i2c_client *client,
if (temp1 != (DS2482_REG_STS_LL | DS2482_REG_STS_RST)) {
dev_warn(&client->dev, "DS2482 reset status "
"0x%02X - not a DS2482\n", temp1);
- goto exit_free;
+ return err;
}
/* Detect the 8-port version */
@@ -522,13 +520,10 @@ exit_w1_remove:
if (data->w1_ch[idx].pdev != NULL)
w1_remove_master_device(&data->w1_ch[idx].w1_bm);
}
-exit_free:
- kfree(data);
-exit:
return err;
}
-static int ds2482_remove(struct i2c_client *client)
+static void ds2482_remove(struct i2c_client *client)
{
struct ds2482_data *data = i2c_get_clientdata(client);
int idx;
@@ -538,14 +533,29 @@ static int ds2482_remove(struct i2c_client *client)
if (data->w1_ch[idx].pdev != NULL)
w1_remove_master_device(&data->w1_ch[idx].w1_bm);
}
-
- /* Free the memory */
- kfree(data);
- return 0;
}
+/*
+ * Driver data (common to all clients)
+ */
+static const struct i2c_device_id ds2482_id[] = {
+ { "ds2482" },
+ { "ds2484" },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ds2482_id);
+
+static struct i2c_driver ds2482_driver = {
+ .driver = {
+ .name = "ds2482",
+ },
+ .probe = ds2482_probe,
+ .remove = ds2482_remove,
+ .id_table = ds2482_id,
+};
module_i2c_driver(ds2482_driver);
MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
MODULE_DESCRIPTION("DS2482 driver");
+
MODULE_LICENSE("GPL");
generated by cgit (git 2.34.1) at 2025-12-25 13:23:52 +0000