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-rw-r--r--Documentation/w1/masters/ds24902
-rw-r--r--drivers/w1/masters/ds2490.c108
2 files changed, 86 insertions, 24 deletions
diff --git a/Documentation/w1/masters/ds2490 b/Documentation/w1/masters/ds2490
index 28176de..3e09115 100644
--- a/Documentation/w1/masters/ds2490
+++ b/Documentation/w1/masters/ds2490
@@ -21,8 +21,6 @@ Notes and limitations.
- The weak pullup current is a minimum of 0.9mA and maximum of 6.0mA.
- The 5V strong pullup is supported with a minimum of 5.9mA and a
maximum of 30.4 mA. (From DS2490.pdf)
-- While the ds2490 supports a hardware search the code doesn't take
- advantage of it (in tested case it only returned first device).
- The hardware will detect when devices are attached to the bus on the
next bus (reset?) operation, however only a message is printed as
the core w1 code doesn't make use of the information. Connecting
diff --git a/drivers/w1/masters/ds2490.c b/drivers/w1/masters/ds2490.c
index cd59e12..db0bf32 100644
--- a/drivers/w1/masters/ds2490.c
+++ b/drivers/w1/masters/ds2490.c
@@ -698,37 +698,102 @@ static int ds_write_block(struct ds_device *dev, u8 *buf, int len)
return !(err == len);
}
-#if 0
-
-static int ds_search(struct ds_device *dev, u64 init, u64 *buf, u8 id_number, int conditional_search)
+static void ds9490r_search(void *data, struct w1_master *master,
+ u8 search_type, w1_slave_found_callback callback)
{
+ /* When starting with an existing id, the first id returned will
+ * be that device (if it is still on the bus most likely).
+ *
+ * If the number of devices found is less than or equal to the
+ * search_limit, that number of IDs will be returned. If there are
+ * more, search_limit IDs will be returned followed by a non-zero
+ * discrepency value.
+ */
+ struct ds_device *dev = data;
int err;
u16 value, index;
struct ds_status st;
+ u8 st_buf[ST_SIZE];
+ int search_limit;
+ int found = 0;
+ int i;
- memset(buf, 0, sizeof(buf));
-
- err = ds_send_data(ds_dev, (unsigned char *)&init, 8);
- if (err)
- return err;
+ /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for
+ * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time.
+ */
+ const unsigned long jtime = msecs_to_jiffies(1000*8/75);
+ /* FIFO 128 bytes, bulk packet size 64, read a multiple of the
+ * packet size.
+ */
+ u64 buf[2*64/8];
- ds_wait_status(ds_dev, &st);
+ /* address to start searching at */
+ if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
+ return;
+ master->search_id = 0;
+
+ value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
+ COMM_RTS;
+ search_limit = master->max_slave_count;
+ if (search_limit > 255)
+ search_limit = 0;
+ index = search_type | (search_limit << 8);
+ if (ds_send_control(dev, value, index) < 0)
+ return;
- value = COMM_SEARCH_ACCESS | COMM_IM | COMM_SM | COMM_F | COMM_RTS;
- index = (conditional_search ? 0xEC : 0xF0) | (id_number << 8);
- err = ds_send_control(ds_dev, value, index);
- if (err)
- return err;
+ do {
+ schedule_timeout(jtime);
- ds_wait_status(ds_dev, &st);
+ if (ds_recv_status_nodump(dev, &st, st_buf, sizeof(st_buf)) <
+ sizeof(st)) {
+ break;
+ }
- err = ds_recv_data(ds_dev, (unsigned char *)buf, 8*id_number);
- if (err < 0)
- return err;
+ if (st.data_in_buffer_status) {
+ /* Bulk in can receive partial ids, but when it does
+ * they fail crc and will be discarded anyway.
+ * That has only been seen when status in buffer
+ * is 0 and bulk is read anyway, so don't read
+ * bulk without first checking if status says there
+ * is data to read.
+ */
+ err = ds_recv_data(dev, (u8 *)buf, sizeof(buf));
+ if (err < 0)
+ break;
+ for (i = 0; i < err/8; ++i) {
+ ++found;
+ if (found <= search_limit)
+ callback(master, buf[i]);
+ /* can't know if there will be a discrepancy
+ * value after until the next id */
+ if (found == search_limit)
+ master->search_id = buf[i];
+ }
+ }
- return err/8;
+ if (test_bit(W1_ABORT_SEARCH, &master->flags))
+ break;
+ } while (!(st.status & (ST_IDLE | ST_HALT)));
+
+ /* only continue the search if some weren't found */
+ if (found <= search_limit) {
+ master->search_id = 0;
+ } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) {
+ /* Only max_slave_count will be scanned in a search,
+ * but it will start where it left off next search
+ * until all ids are identified and then it will start
+ * over. A continued search will report the previous
+ * last id as the first id (provided it is still on the
+ * bus).
+ */
+ dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, "
+ "will continue next search.\n", __func__,
+ master->max_slave_count);
+ set_bit(W1_WARN_MAX_COUNT, &master->flags);
+ }
}
+#if 0
static int ds_match_access(struct ds_device *dev, u64 init)
{
int err;
@@ -902,6 +967,7 @@ static int ds_w1_init(struct ds_device *dev)
dev->master.write_block = &ds9490r_write_block;
dev->master.reset_bus = &ds9490r_reset;
dev->master.set_pullup = &ds9490r_set_pullup;
+ dev->master.search = &ds9490r_search;
return w1_add_master_device(&dev->master);
}
@@ -920,13 +986,11 @@ static int ds_probe(struct usb_interface *intf,
struct ds_device *dev;
int i, err, alt;
- dev = kmalloc(sizeof(struct ds_device), GFP_KERNEL);
+ dev = kzalloc(sizeof(struct ds_device), GFP_KERNEL);
if (!dev) {
printk(KERN_INFO "Failed to allocate new DS9490R structure.\n");
return -ENOMEM;
}
- dev->spu_sleep = 0;
- dev->spu_bit = 0;
dev->udev = usb_get_dev(udev);
if (!dev->udev) {
err = -ENOMEM;
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