drivers: w1: Add 1w slave driver for DS28E05 EEPROM
Add a one wire driver for the DS28E05 one wire slave chip. This chip requires OverDrive support to talk to it. Signed-off-by: Andrew Worsley <amworsley@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andrew Worsley
Greg Kroah-Hartman
parent
54865314f5
commit
f6887531c0
|
|
@ -65,6 +65,14 @@ config W1_SLAVE_DS2423
|
|||
Say Y here if you want to use a 1-wire
|
||||
counter family device (DS2423).
|
||||
|
||||
config W1_SLAVE_DS2805
|
||||
tristate "112-byte EEPROM support (DS28E05)"
|
||||
help
|
||||
Say Y here if you want to use a 1-wire
|
||||
is a 112-byte user-programmable EEPROM is
|
||||
organized as 7 pages of 16 bytes each with 64bit
|
||||
unique number. Requires OverDrive Speed to talk to.
|
||||
|
||||
config W1_SLAVE_DS2431
|
||||
tristate "1kb EEPROM family support (DS2431)"
|
||||
help
|
||||
|
|
|
|||
|
|
@ -10,6 +10,7 @@ obj-$(CONFIG_W1_SLAVE_DS2413) += w1_ds2413.o
|
|||
obj-$(CONFIG_W1_SLAVE_DS2406) += w1_ds2406.o
|
||||
obj-$(CONFIG_W1_SLAVE_DS2423) += w1_ds2423.o
|
||||
obj-$(CONFIG_W1_SLAVE_DS2431) += w1_ds2431.o
|
||||
obj-$(CONFIG_W1_SLAVE_DS2805) += w1_ds2805.o
|
||||
obj-$(CONFIG_W1_SLAVE_DS2433) += w1_ds2433.o
|
||||
obj-$(CONFIG_W1_SLAVE_DS2438) += w1_ds2438.o
|
||||
obj-$(CONFIG_W1_SLAVE_DS2760) += w1_ds2760.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,313 @@
|
|||
/*
|
||||
* w1_ds2805 - w1 family 0d (DS28E05) driver
|
||||
*
|
||||
* Copyright (c) 2016 Andrew Worsley amworsley@gmail.com
|
||||
*
|
||||
* This source code is licensed under the GNU General Public License,
|
||||
* Version 2. See the file COPYING for more details.
|
||||
*/
|
||||
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/moduleparam.h>
|
||||
#include <linux/device.h>
|
||||
#include <linux/types.h>
|
||||
#include <linux/delay.h>
|
||||
|
||||
#include <linux/w1.h>
|
||||
|
||||
#define W1_EEPROM_DS2805 0x0D
|
||||
|
||||
#define W1_F0D_EEPROM_SIZE 128
|
||||
#define W1_F0D_PAGE_BITS 3
|
||||
#define W1_F0D_PAGE_SIZE (1<<W1_F0D_PAGE_BITS)
|
||||
#define W1_F0D_PAGE_MASK 0x0F
|
||||
|
||||
#define W1_F0D_SCRATCH_BITS 1
|
||||
#define W1_F0D_SCRATCH_SIZE (1<<W1_F0D_SCRATCH_BITS)
|
||||
#define W1_F0D_SCRATCH_MASK (W1_F0D_SCRATCH_SIZE-1)
|
||||
|
||||
#define W1_F0D_READ_EEPROM 0xF0
|
||||
#define W1_F0D_WRITE_EEPROM 0x55
|
||||
#define W1_F0D_RELEASE 0xFF
|
||||
|
||||
#define W1_F0D_CS_OK 0xAA /* Chip Status Ok */
|
||||
|
||||
#define W1_F0D_TPROG_MS 16
|
||||
|
||||
#define W1_F0D_READ_RETRIES 10
|
||||
#define W1_F0D_READ_MAXLEN W1_F0D_EEPROM_SIZE
|
||||
|
||||
/*
|
||||
* Check the file size bounds and adjusts count as needed.
|
||||
* This would not be needed if the file size didn't reset to 0 after a write.
|
||||
*/
|
||||
static inline size_t w1_f0d_fix_count(loff_t off, size_t count, size_t size)
|
||||
{
|
||||
if (off > size)
|
||||
return 0;
|
||||
|
||||
if ((off + count) > size)
|
||||
return size - off;
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
/*
|
||||
* Read a block from W1 ROM two times and compares the results.
|
||||
* If they are equal they are returned, otherwise the read
|
||||
* is repeated W1_F0D_READ_RETRIES times.
|
||||
*
|
||||
* count must not exceed W1_F0D_READ_MAXLEN.
|
||||
*/
|
||||
static int w1_f0d_readblock(struct w1_slave *sl, int off, int count, char *buf)
|
||||
{
|
||||
u8 wrbuf[3];
|
||||
u8 cmp[W1_F0D_READ_MAXLEN];
|
||||
int tries = W1_F0D_READ_RETRIES;
|
||||
|
||||
do {
|
||||
wrbuf[0] = W1_F0D_READ_EEPROM;
|
||||
wrbuf[1] = off & 0x7f;
|
||||
wrbuf[2] = 0;
|
||||
|
||||
if (w1_reset_select_slave(sl))
|
||||
return -1;
|
||||
|
||||
w1_write_block(sl->master, wrbuf, sizeof(wrbuf));
|
||||
w1_read_block(sl->master, buf, count);
|
||||
|
||||
if (w1_reset_select_slave(sl))
|
||||
return -1;
|
||||
|
||||
w1_write_block(sl->master, wrbuf, sizeof(wrbuf));
|
||||
w1_read_block(sl->master, cmp, count);
|
||||
|
||||
if (!memcmp(cmp, buf, count))
|
||||
return 0;
|
||||
} while (--tries);
|
||||
|
||||
dev_err(&sl->dev, "proof reading failed %d times\n",
|
||||
W1_F0D_READ_RETRIES);
|
||||
|
||||
return -1;
|
||||
}
|
||||
|
||||
static ssize_t w1_f0d_read_bin(struct file *filp, struct kobject *kobj,
|
||||
struct bin_attribute *bin_attr,
|
||||
char *buf, loff_t off, size_t count)
|
||||
{
|
||||
struct w1_slave *sl = kobj_to_w1_slave(kobj);
|
||||
int todo = count;
|
||||
|
||||
count = w1_f0d_fix_count(off, count, W1_F0D_EEPROM_SIZE);
|
||||
if (count == 0)
|
||||
return 0;
|
||||
|
||||
mutex_lock(&sl->master->mutex);
|
||||
|
||||
/* read directly from the EEPROM in chunks of W1_F0D_READ_MAXLEN */
|
||||
while (todo > 0) {
|
||||
int block_read;
|
||||
|
||||
if (todo >= W1_F0D_READ_MAXLEN)
|
||||
block_read = W1_F0D_READ_MAXLEN;
|
||||
else
|
||||
block_read = todo;
|
||||
|
||||
if (w1_f0d_readblock(sl, off, block_read, buf) < 0) {
|
||||
count = -EIO;
|
||||
break;
|
||||
}
|
||||
|
||||
todo -= W1_F0D_READ_MAXLEN;
|
||||
buf += W1_F0D_READ_MAXLEN;
|
||||
off += W1_F0D_READ_MAXLEN;
|
||||
}
|
||||
|
||||
mutex_unlock(&sl->master->mutex);
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
/*
|
||||
* Writes to the scratchpad and reads it back for verification.
|
||||
* Then copies the scratchpad to EEPROM.
|
||||
* The data must be aligned at W1_F0D_SCRATCH_SIZE bytes and
|
||||
* must be W1_F0D_SCRATCH_SIZE bytes long.
|
||||
* The master must be locked.
|
||||
*
|
||||
* @param sl The slave structure
|
||||
* @param addr Address for the write
|
||||
* @param len length must be <= (W1_F0D_PAGE_SIZE - (addr & W1_F0D_PAGE_MASK))
|
||||
* @param data The data to write
|
||||
* @return 0=Success -1=failure
|
||||
*/
|
||||
static int w1_f0d_write(struct w1_slave *sl, int addr, int len, const u8 *data)
|
||||
{
|
||||
int tries = W1_F0D_READ_RETRIES;
|
||||
u8 wrbuf[3];
|
||||
u8 rdbuf[W1_F0D_SCRATCH_SIZE];
|
||||
u8 cs;
|
||||
|
||||
if ((addr & 1) || (len != 2)) {
|
||||
dev_err(&sl->dev, "%s: bad addr/len - addr=%#x len=%d\n",
|
||||
__func__, addr, len);
|
||||
return -1;
|
||||
}
|
||||
|
||||
retry:
|
||||
|
||||
/* Write the data to the scratchpad */
|
||||
if (w1_reset_select_slave(sl))
|
||||
return -1;
|
||||
|
||||
wrbuf[0] = W1_F0D_WRITE_EEPROM;
|
||||
wrbuf[1] = addr & 0xff;
|
||||
wrbuf[2] = 0xff; /* ?? from Example */
|
||||
|
||||
w1_write_block(sl->master, wrbuf, sizeof(wrbuf));
|
||||
w1_write_block(sl->master, data, len);
|
||||
|
||||
w1_read_block(sl->master, rdbuf, sizeof(rdbuf));
|
||||
/* Compare what was read against the data written */
|
||||
if ((rdbuf[0] != data[0]) || (rdbuf[1] != data[1])) {
|
||||
|
||||
if (--tries)
|
||||
goto retry;
|
||||
|
||||
dev_err(&sl->dev,
|
||||
"could not write to eeprom, scratchpad compare failed %d times\n",
|
||||
W1_F0D_READ_RETRIES);
|
||||
pr_info("%s: rdbuf = %#x %#x data = %#x %#x\n",
|
||||
__func__, rdbuf[0], rdbuf[1], data[0], data[1]);
|
||||
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* Trigger write out to EEPROM */
|
||||
w1_write_8(sl->master, W1_F0D_RELEASE);
|
||||
|
||||
/* Sleep for tprog ms to wait for the write to complete */
|
||||
msleep(W1_F0D_TPROG_MS);
|
||||
|
||||
/* Check CS (Command Status) == 0xAA ? */
|
||||
cs = w1_read_8(sl->master);
|
||||
if (cs != W1_F0D_CS_OK) {
|
||||
dev_err(&sl->dev, "save to eeprom failed = CS=%#x\n", cs);
|
||||
return -1;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static ssize_t w1_f0d_write_bin(struct file *filp, struct kobject *kobj,
|
||||
struct bin_attribute *bin_attr,
|
||||
char *buf, loff_t off, size_t count)
|
||||
{
|
||||
struct w1_slave *sl = kobj_to_w1_slave(kobj);
|
||||
int addr, len;
|
||||
int copy;
|
||||
|
||||
count = w1_f0d_fix_count(off, count, W1_F0D_EEPROM_SIZE);
|
||||
if (count == 0)
|
||||
return 0;
|
||||
|
||||
mutex_lock(&sl->master->mutex);
|
||||
|
||||
/* Can only write data in blocks of the size of the scratchpad */
|
||||
addr = off;
|
||||
len = count;
|
||||
while (len > 0) {
|
||||
|
||||
/* if len too short or addr not aligned */
|
||||
if (len < W1_F0D_SCRATCH_SIZE || addr & W1_F0D_SCRATCH_MASK) {
|
||||
char tmp[W1_F0D_SCRATCH_SIZE];
|
||||
|
||||
/* read the block and update the parts to be written */
|
||||
if (w1_f0d_readblock(sl, addr & ~W1_F0D_SCRATCH_MASK,
|
||||
W1_F0D_SCRATCH_SIZE, tmp)) {
|
||||
count = -EIO;
|
||||
goto out_up;
|
||||
}
|
||||
|
||||
/* copy at most to the boundary of the PAGE or len */
|
||||
copy = W1_F0D_SCRATCH_SIZE -
|
||||
(addr & W1_F0D_SCRATCH_MASK);
|
||||
|
||||
if (copy > len)
|
||||
copy = len;
|
||||
|
||||
memcpy(&tmp[addr & W1_F0D_SCRATCH_MASK], buf, copy);
|
||||
if (w1_f0d_write(sl, addr & ~W1_F0D_SCRATCH_MASK,
|
||||
W1_F0D_SCRATCH_SIZE, tmp) < 0) {
|
||||
count = -EIO;
|
||||
goto out_up;
|
||||
}
|
||||
} else {
|
||||
|
||||
copy = W1_F0D_SCRATCH_SIZE;
|
||||
if (w1_f0d_write(sl, addr, copy, buf) < 0) {
|
||||
count = -EIO;
|
||||
goto out_up;
|
||||
}
|
||||
}
|
||||
buf += copy;
|
||||
addr += copy;
|
||||
len -= copy;
|
||||
}
|
||||
|
||||
out_up:
|
||||
mutex_unlock(&sl->master->mutex);
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
static struct bin_attribute w1_f0d_bin_attr = {
|
||||
.attr = {
|
||||
.name = "eeprom",
|
||||
.mode = S_IRUGO | S_IWUSR,
|
||||
},
|
||||
.size = W1_F0D_EEPROM_SIZE,
|
||||
.read = w1_f0d_read_bin,
|
||||
.write = w1_f0d_write_bin,
|
||||
};
|
||||
|
||||
static int w1_f0d_add_slave(struct w1_slave *sl)
|
||||
{
|
||||
return sysfs_create_bin_file(&sl->dev.kobj, &w1_f0d_bin_attr);
|
||||
}
|
||||
|
||||
static void w1_f0d_remove_slave(struct w1_slave *sl)
|
||||
{
|
||||
sysfs_remove_bin_file(&sl->dev.kobj, &w1_f0d_bin_attr);
|
||||
}
|
||||
|
||||
static struct w1_family_ops w1_f0d_fops = {
|
||||
.add_slave = w1_f0d_add_slave,
|
||||
.remove_slave = w1_f0d_remove_slave,
|
||||
};
|
||||
|
||||
static struct w1_family w1_family_2d = {
|
||||
.fid = W1_EEPROM_DS2805,
|
||||
.fops = &w1_f0d_fops,
|
||||
};
|
||||
|
||||
static int __init w1_f0d_init(void)
|
||||
{
|
||||
pr_info("%s()\n", __func__);
|
||||
return w1_register_family(&w1_family_2d);
|
||||
}
|
||||
|
||||
static void __exit w1_f0d_fini(void)
|
||||
{
|
||||
pr_info("%s()\n", __func__);
|
||||
w1_unregister_family(&w1_family_2d);
|
||||
}
|
||||
|
||||
module_init(w1_f0d_init);
|
||||
module_exit(w1_f0d_fini);
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_AUTHOR("Andrew Worsley amworsley@gmail.com");
|
||||
MODULE_DESCRIPTION("w1 family 0d driver for DS2805, 1kb EEPROM");
|
||||
|
|
@ -729,6 +729,8 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
|
|||
atomic_set(&sl->refcnt, 1);
|
||||
atomic_inc(&sl->master->refcnt);
|
||||
dev->slave_count++;
|
||||
dev_info(&dev->dev, "Attaching one wire slave %02x.%012llx crc %02x\n",
|
||||
rn->family, (unsigned long long)rn->id, rn->crc);
|
||||
|
||||
/* slave modules need to be loaded in a context with unlocked mutex */
|
||||
mutex_unlock(&dev->mutex);
|
||||
|
|
|
|||
Loading…
Reference in New Issue