[PATCH 6/7] w1: ds2433: add support for ds28ec20 eeprom
From: marc . ferland
Date: Fri Nov 17 2023 - 14:30:34 EST
From: Marc Ferland <marc.ferland@xxxxxxxxxxxx>
The ds28ec20 eeprom is (almost) backward compatible with the
ds2433. The only major differences are:
- the eeprom size is now 2560 bytes instead of 512;
- the number of pages is now 80 (same page size as the ds2433: 256 bits);
- the programming time has increased from 5ms to 10ms;
This patch adds support for the ds28ec20 to the ds2433 driver. From
the datasheet: The DS28EC20 provides a high degree of backward
compatibility with the DS2433. Besides the different family codes, the
only protocol change that is required on an existing DS2433
implementation is a lengthening of the programming duration (tPROG)
from 5ms to 10ms.
Tests:
dmesg now returns:
w1_master_driver w1_bus_master1: Attaching one wire slave 43.000000478756 crc e0
instead of:
w1_master_driver w1_bus_master1: Attaching one wire slave 43.000000478756 crc e0
w1_master_driver w1_bus_master1: Family 43 for 43.000000478756.e0 is not registered.
Test script:
#!/bin/sh
EEPROM=/sys/bus/w1/devices/43-000000478756/eeprom
BINFILE1=/home/root/file1.bin
BINFILE2=/home/root/file2.bin
for BS in 1 2 3 4 8 16 32 64 128 256 512 1024 2560; do
dd if=/dev/random of=${BINFILE1} bs=${BS} count=1 status=none
dd if=${BINFILE1} of=${EEPROM} status=none
dd if=${EEPROM} of=${BINFILE2} bs=${BS} count=1 status=none
if ! cmp --silent ${BINFILE1} ${BINFILE2}; then
echo file1
hexdump ${BINFILE1}
echo file2
hexdump ${BINFILE2}
echo FAIL
exit 1
fi
echo "${BS} OK!"
done
Test results (CONFIG_W1_SLAVE_DS2433_CRC is not set):
$ cat /proc/config.gz | gunzip | grep CONFIG_W1_SLAVE_DS2433
CONFIG_W1_SLAVE_DS2433=m
# CONFIG_W1_SLAVE_DS2433_CRC is not set
# ./test.sh
1 OK!
2 OK!
3 OK!
4 OK!
8 OK!
16 OK!
32 OK!
64 OK!
128 OK!
256 OK!
512 OK!
1024 OK!
2560 OK!
Test results (CONFIG_W1_SLAVE_DS2433_CRC=y):
$ cat /proc/config.gz | gunzip | grep CONFIG_W1_SLAVE_DS2433
CONFIG_W1_SLAVE_DS2433=m
CONFIG_W1_SLAVE_DS2433_CRC=y
# create a 32 bytes block with a crc, i.e.:
00000000 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000010 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
# fill all 80 blocks
$ dd if=test.bin of=/sys/bus/w1/devices/43-000000478756/eeprom bs=32 count=80
# read back all blocks, i.e.:
$ hexdump -C /sys/bus/w1/devices/43-000000478756/eeprom
00000000 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000010 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
00000020 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000030 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
...
000009e0 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
000009f0 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
00000a00
Signed-off-by: Marc Ferland <marc.ferland@xxxxxxxxxxxx>
---
drivers/w1/slaves/w1_ds2433.c | 84 +++++++++++++++++++++++++++++++----
1 file changed, 75 insertions(+), 9 deletions(-)
diff --git a/drivers/w1/slaves/w1_ds2433.c b/drivers/w1/slaves/w1_ds2433.c
index 04c3eee9e5d7..69bdf3dba573 100644
--- a/drivers/w1/slaves/w1_ds2433.c
+++ b/drivers/w1/slaves/w1_ds2433.c
@@ -1,8 +1,9 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * w1_ds2433.c - w1 family 23 (DS2433) driver
+ * w1_ds2433.c - w1 family 23 (DS2433) & 43 (DS28EC20) eeprom driver
*
* Copyright (c) 2005 Ben Gardner <bgardner@xxxxxxxxxx>
+ * Copyright (c) 2023 Marc Ferland <marc.ferland@xxxxxxxxxxxx>
*/
#include <linux/kernel.h>
@@ -23,6 +24,7 @@
#include <linux/w1.h>
#define W1_F23_EEPROM_DS2433 0x23
+#define W1_F43_EEPROM_DS28EC20 0x43
#define W1_PAGE_SIZE 32
#define W1_PAGE_BITS 5
@@ -45,10 +47,16 @@ static const struct ds2433_config config_f23 = {
.tprog = 5,
};
+static const struct ds2433_config config_f43 = {
+ .eeprom_size = 2560,
+ .page_count = 80,
+ .tprog = 10,
+};
+
struct w1_data {
#ifdef CONFIG_W1_SLAVE_DS2433_CRC
- u8 *memory;
- u32 validcrc;
+ u8 *memory;
+ unsigned long *validcrc;
#endif
const struct ds2433_config *cfg;
};
@@ -75,11 +83,11 @@ static int w1_f23_refresh_block(struct w1_slave *sl, struct w1_data *data,
u8 wrbuf[3];
int off = block * W1_PAGE_SIZE;
- if (data->validcrc & (1 << block))
+ if (test_bit(block, data->validcrc))
return 0;
if (w1_reset_select_slave(sl)) {
- data->validcrc = 0;
+ bitmap_zero(data->validcrc, data->cfg->page_count);
return -EIO;
}
@@ -91,7 +99,7 @@ static int w1_f23_refresh_block(struct w1_slave *sl, struct w1_data *data,
/* cache the block if the CRC is valid */
if (crc16(CRC16_INIT, &data->memory[off], W1_PAGE_SIZE) == CRC16_VALID)
- data->validcrc |= (1 << block);
+ set_bit(block, data->validcrc);
return 0;
}
@@ -206,7 +214,7 @@ static int w1_f23_write(struct w1_slave *sl, int addr, int len, const u8 *data)
/* Reset the bus to wake up the EEPROM (this may not be needed) */
w1_reset_bus(sl->master);
#ifdef CONFIG_W1_SLAVE_DS2433_CRC
- fdata->validcrc &= ~(1 << (addr >> W1_PAGE_BITS));
+ clear_bit(addr >> W1_PAGE_BITS, fdata->validcrc);
#endif
return 0;
}
@@ -269,6 +277,13 @@ static struct bin_attribute bin_attr_f23_eeprom = {
.size = config_f23.eeprom_size,
};
+static struct bin_attribute bin_attr_f43_eeprom = {
+ .attr = { .name = "eeprom", .mode = 0644 },
+ .read = eeprom_read,
+ .write = eeprom_write,
+ .size = config_f43.eeprom_size,
+};
+
static struct bin_attribute *w1_f23_bin_attributes[] = {
&bin_attr_f23_eeprom,
NULL,
@@ -283,6 +298,20 @@ static const struct attribute_group *w1_f23_groups[] = {
NULL,
};
+static struct bin_attribute *w1_f43_bin_attributes[] = {
+ &bin_attr_f43_eeprom,
+ NULL,
+};
+
+static const struct attribute_group w1_f43_group = {
+ .bin_attrs = w1_f43_bin_attributes,
+};
+
+static const struct attribute_group *w1_f43_groups[] = {
+ &w1_f43_group,
+ NULL,
+};
+
static int w1_add_slave(struct w1_slave *sl)
{
struct w1_data *data;
@@ -291,7 +320,14 @@ static int w1_add_slave(struct w1_slave *sl)
if (!data)
return -ENOMEM;
- data->cfg = &config_f23;
+ switch (sl->family->fid) {
+ case W1_F23_EEPROM_DS2433:
+ data->cfg = &config_f23;
+ break;
+ case W1_F43_EEPROM_DS28EC20:
+ data->cfg = &config_f43;
+ break;
+ }
#ifdef CONFIG_W1_SLAVE_DS2433_CRC
data->memory = kzalloc(data->cfg->eeprom_size, GFP_KERNEL);
@@ -299,6 +335,13 @@ static int w1_add_slave(struct w1_slave *sl)
kfree(data);
return -ENOMEM;
}
+ data->validcrc = bitmap_zalloc(data->cfg->page_count,
+ GFP_KERNEL);
+ if (!data->validcrc) {
+ kfree(data->memory);
+ kfree(data);
+ return -ENOMEM;
+ }
#endif /* CONFIG_W1_SLAVE_DS2433_CRC */
sl->family_data = data;
@@ -310,6 +353,7 @@ static void w1_remove_slave(struct w1_slave *sl)
struct w1_data *data = sl->family_data;
#ifdef CONFIG_W1_SLAVE_DS2433_CRC
kfree(data->memory);
+ bitmap_free(data->validcrc);
#endif /* CONFIG_W1_SLAVE_DS2433_CRC */
kfree(data);
sl->family_data = NULL;
@@ -321,11 +365,22 @@ static const struct w1_family_ops w1_f23_fops = {
.groups = w1_f23_groups,
};
+static const struct w1_family_ops w1_f43_fops = {
+ .add_slave = w1_add_slave,
+ .remove_slave = w1_remove_slave,
+ .groups = w1_f43_groups,
+};
+
static struct w1_family w1_family_23 = {
.fid = W1_F23_EEPROM_DS2433,
.fops = &w1_f23_fops,
};
+static struct w1_family w1_family_43 = {
+ .fid = W1_F43_EEPROM_DS28EC20,
+ .fops = &w1_f43_fops,
+};
+
static int __init w1_ds2433_init(void)
{
int err;
@@ -334,18 +389,29 @@ static int __init w1_ds2433_init(void)
if (err)
return err;
+ err = w1_register_family(&w1_family_43);
+ if (err)
+ goto err_43;
+
return 0;
+
+err_43:
+ w1_unregister_family(&w1_family_23);
+ return err;
}
static void __exit w1_ds2433_exit(void)
{
w1_unregister_family(&w1_family_23);
+ w1_unregister_family(&w1_family_43);
}
module_init(w1_ds2433_init);
module_exit(w1_ds2433_exit);
MODULE_AUTHOR("Ben Gardner <bgardner@xxxxxxxxxx>");
-MODULE_DESCRIPTION("w1 family 23 driver for DS2433, 4kb EEPROM");
+MODULE_AUTHOR("Marc Ferland <marc.ferland@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("w1 family 23/43 driver for DS2433 (4kb) and DS28EC20 (20kb)");
MODULE_LICENSE("GPL");
MODULE_ALIAS("w1-family-" __stringify(W1_F23_EEPROM_DS2433));
+MODULE_ALIAS("w1-family-" __stringify(W1_F43_EEPROM_DS28EC20));
--
2.34.1