summaryrefslogtreecommitdiff
path: root/drivers/w1
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/w1')
-rw-r--r--drivers/w1/slaves/Kconfig8
-rw-r--r--drivers/w1/slaves/Makefile1
-rw-r--r--drivers/w1/slaves/w1_ds2430.c295
3 files changed, 304 insertions, 0 deletions
diff --git a/drivers/w1/slaves/Kconfig b/drivers/w1/slaves/Kconfig
index b7847636501d..687753889c34 100644
--- a/drivers/w1/slaves/Kconfig
+++ b/drivers/w1/slaves/Kconfig
@@ -74,6 +74,14 @@ config W1_SLAVE_DS2805
organized as 7 pages of 16 bytes each with 64bit
unique number. Requires OverDrive Speed to talk to.
+config W1_SLAVE_DS2430
+ tristate "256b EEPROM family support (DS2430)"
+ help
+ Say Y here if you want to use a 1-wire 256bit EEPROM
+ family device (DS2430).
+ This EEPROM is organized as one page of 32 bytes for random
+ access.
+
config W1_SLAVE_DS2431
tristate "1kb EEPROM family support (DS2431)"
help
diff --git a/drivers/w1/slaves/Makefile b/drivers/w1/slaves/Makefile
index 8e9655eaa478..278bcf2a9bfd 100644
--- a/drivers/w1/slaves/Makefile
+++ b/drivers/w1/slaves/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_W1_SLAVE_DS2408) += w1_ds2408.o
obj-$(CONFIG_W1_SLAVE_DS2413) += w1_ds2413.o
obj-$(CONFIG_W1_SLAVE_DS2406) += w1_ds2406.o
obj-$(CONFIG_W1_SLAVE_DS2423) += w1_ds2423.o
+obj-$(CONFIG_W1_SLAVE_DS2430) += w1_ds2430.o
obj-$(CONFIG_W1_SLAVE_DS2431) += w1_ds2431.o
obj-$(CONFIG_W1_SLAVE_DS2805) += w1_ds2805.o
obj-$(CONFIG_W1_SLAVE_DS2433) += w1_ds2433.o
diff --git a/drivers/w1/slaves/w1_ds2430.c b/drivers/w1/slaves/w1_ds2430.c
new file mode 100644
index 000000000000..6fb0563fb2ae
--- /dev/null
+++ b/drivers/w1/slaves/w1_ds2430.c
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * w1_ds2430.c - w1 family 14 (DS2430) driver
+ **
+ * Copyright (c) 2019 Angelo Dureghello <angelo.dureghello@timesys.com>
+ *
+ * Cloned and modified from ds2431
+ * Copyright (c) 2008 Bernhard Weirich <bernhard.weirich@riedel.net>
+ *
+ */
+
+#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_DS2430 0x14
+
+#define W1_F14_EEPROM_SIZE 32
+#define W1_F14_PAGE_COUNT 1
+#define W1_F14_PAGE_BITS 5
+#define W1_F14_PAGE_SIZE (1 << W1_F14_PAGE_BITS)
+#define W1_F14_PAGE_MASK 0x1F
+
+#define W1_F14_SCRATCH_BITS 5
+#define W1_F14_SCRATCH_SIZE (1 << W1_F14_SCRATCH_BITS)
+#define W1_F14_SCRATCH_MASK (W1_F14_SCRATCH_SIZE-1)
+
+#define W1_F14_READ_EEPROM 0xF0
+#define W1_F14_WRITE_SCRATCH 0x0F
+#define W1_F14_READ_SCRATCH 0xAA
+#define W1_F14_COPY_SCRATCH 0x55
+#define W1_F14_VALIDATION_KEY 0xa5
+
+#define W1_F14_TPROG_MS 11
+#define W1_F14_READ_RETRIES 10
+#define W1_F14_READ_MAXLEN W1_F14_SCRATCH_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_f14_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_F14_READ_RETRIES times.
+ *
+ * count must not exceed W1_F14_READ_MAXLEN.
+ */
+static int w1_f14_readblock(struct w1_slave *sl, int off, int count, char *buf)
+{
+ u8 wrbuf[2];
+ u8 cmp[W1_F14_READ_MAXLEN];
+ int tries = W1_F14_READ_RETRIES;
+
+ do {
+ wrbuf[0] = W1_F14_READ_EEPROM;
+ wrbuf[1] = off & 0xff;
+
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ w1_write_block(sl->master, wrbuf, 2);
+ w1_read_block(sl->master, buf, count);
+
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ w1_write_block(sl->master, wrbuf, 2);
+ 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_F14_READ_RETRIES);
+
+ return -1;
+}
+
+static ssize_t eeprom_read(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_f14_fix_count(off, count, W1_F14_EEPROM_SIZE);
+ if (count == 0)
+ return 0;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ /* read directly from the EEPROM in chunks of W1_F14_READ_MAXLEN */
+ while (todo > 0) {
+ int block_read;
+
+ if (todo >= W1_F14_READ_MAXLEN)
+ block_read = W1_F14_READ_MAXLEN;
+ else
+ block_read = todo;
+
+ if (w1_f14_readblock(sl, off, block_read, buf) < 0)
+ count = -EIO;
+
+ todo -= W1_F14_READ_MAXLEN;
+ buf += W1_F14_READ_MAXLEN;
+ off += W1_F14_READ_MAXLEN;
+ }
+
+ mutex_unlock(&sl->master->bus_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_F14_SCRATCH_SIZE bytes and
+ * must be W1_F14_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_F14_PAGE_SIZE - (addr & W1_F14_PAGE_MASK))
+ * @param data The data to write
+ * @return 0=Success -1=failure
+ */
+static int w1_f14_write(struct w1_slave *sl, int addr, int len, const u8 *data)
+{
+ int tries = W1_F14_READ_RETRIES;
+ u8 wrbuf[2];
+ u8 rdbuf[W1_F14_SCRATCH_SIZE + 3];
+
+retry:
+
+ /* Write the data to the scratchpad */
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ wrbuf[0] = W1_F14_WRITE_SCRATCH;
+ wrbuf[1] = addr & 0xff;
+
+ w1_write_block(sl->master, wrbuf, 2);
+ w1_write_block(sl->master, data, len);
+
+ /* Read the scratchpad and verify */
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ w1_write_8(sl->master, W1_F14_READ_SCRATCH);
+ w1_read_block(sl->master, rdbuf, len + 2);
+
+ /*
+ * Compare what was read against the data written
+ * Note: on read scratchpad, device returns 2 bulk 0xff bytes,
+ * to be discarded.
+ */
+ if ((memcmp(data, &rdbuf[2], len) != 0)) {
+
+ if (--tries)
+ goto retry;
+
+ dev_err(&sl->dev,
+ "could not write to eeprom, scratchpad compare failed %d times\n",
+ W1_F14_READ_RETRIES);
+
+ return -1;
+ }
+
+ /* Copy the scratchpad to EEPROM */
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ wrbuf[0] = W1_F14_COPY_SCRATCH;
+ wrbuf[1] = W1_F14_VALIDATION_KEY;
+ w1_write_block(sl->master, wrbuf, 2);
+
+ /* Sleep for tprog ms to wait for the write to complete */
+ msleep(W1_F14_TPROG_MS);
+
+ /* Reset the bus to wake up the EEPROM */
+ w1_reset_bus(sl->master);
+
+ return 0;
+}
+
+static ssize_t eeprom_write(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_f14_fix_count(off, count, W1_F14_EEPROM_SIZE);
+ if (count == 0)
+ return 0;
+
+ mutex_lock(&sl->master->bus_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_F14_SCRATCH_SIZE || addr & W1_F14_SCRATCH_MASK) {
+ char tmp[W1_F14_SCRATCH_SIZE];
+
+ /* read the block and update the parts to be written */
+ if (w1_f14_readblock(sl, addr & ~W1_F14_SCRATCH_MASK,
+ W1_F14_SCRATCH_SIZE, tmp)) {
+ count = -EIO;
+ goto out_up;
+ }
+
+ /* copy at most to the boundary of the PAGE or len */
+ copy = W1_F14_SCRATCH_SIZE -
+ (addr & W1_F14_SCRATCH_MASK);
+
+ if (copy > len)
+ copy = len;
+
+ memcpy(&tmp[addr & W1_F14_SCRATCH_MASK], buf, copy);
+ if (w1_f14_write(sl, addr & ~W1_F14_SCRATCH_MASK,
+ W1_F14_SCRATCH_SIZE, tmp) < 0) {
+ count = -EIO;
+ goto out_up;
+ }
+ } else {
+
+ copy = W1_F14_SCRATCH_SIZE;
+ if (w1_f14_write(sl, addr, copy, buf) < 0) {
+ count = -EIO;
+ goto out_up;
+ }
+ }
+ buf += copy;
+ addr += copy;
+ len -= copy;
+ }
+
+out_up:
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return count;
+}
+
+static BIN_ATTR_RW(eeprom, W1_F14_EEPROM_SIZE);
+
+static struct bin_attribute *w1_f14_bin_attrs[] = {
+ &bin_attr_eeprom,
+ NULL,
+};
+
+static const struct attribute_group w1_f14_group = {
+ .bin_attrs = w1_f14_bin_attrs,
+};
+
+static const struct attribute_group *w1_f14_groups[] = {
+ &w1_f14_group,
+ NULL,
+};
+
+static struct w1_family_ops w1_f14_fops = {
+ .groups = w1_f14_groups,
+};
+
+static struct w1_family w1_family_14 = {
+ .fid = W1_EEPROM_DS2430,
+ .fops = &w1_f14_fops,
+};
+module_w1_family(w1_family_14);
+
+MODULE_AUTHOR("Angelo Dureghello <angelo.dureghello@timesys.com>");
+MODULE_DESCRIPTION("w1 family 14 driver for DS2430, 256kb EEPROM");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("w1-family-" __stringify(W1_EEPROM_DS2430));
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 23:41:56 +0000