From af00a2d5a047455b35d1e7dc4c7d9993c2bcfb93 Mon Sep 17 00:00:00 2001 From: David Fries Date: Wed, 15 Oct 2008 22:04:53 -0700 Subject: [PATCH] W1: w1_int.c use first available master number Follow the example of other devices (like the joystick device). Pick the first available id for each detected device. Currently for USB devices, suspending and resuming would cause the number to increment. Signed-off-by: David Fries Signed-off-by: Evgeniy Polyakov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/w1/w1_int.c | 32 ++++++++++++++++++++++++++------ 1 file changed, 26 insertions(+), 6 deletions(-) diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c index 3fd6e6651fb..a3a54567bfb 100644 --- a/drivers/w1/w1_int.c +++ b/drivers/w1/w1_int.c @@ -29,7 +29,6 @@ #include "w1_netlink.h" #include "w1_int.h" -static u32 w1_ids = 1; static int w1_search_count = -1; /* Default is continual scan */ module_param_named(search_count, w1_search_count, int, 0); @@ -102,9 +101,10 @@ static void w1_free_dev(struct w1_master *dev) int w1_add_master_device(struct w1_bus_master *master) { - struct w1_master *dev; + struct w1_master *dev, *entry; int retval = 0; struct w1_netlink_msg msg; + int id, found; /* validate minimum functionality */ if (!(master->touch_bit && master->reset_bus) && @@ -126,13 +126,33 @@ int w1_add_master_device(struct w1_bus_master *master) master->set_pullup = NULL; } - dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_master_driver, &w1_master_device); - if (!dev) + /* Lock until the device is added (or not) to w1_masters. */ + mutex_lock(&w1_mlock); + /* Search for the first available id (starting at 1). */ + id = 0; + do { + ++id; + found = 0; + list_for_each_entry(entry, &w1_masters, w1_master_entry) { + if (entry->id == id) { + found = 1; + break; + } + } + } while (found); + + dev = w1_alloc_dev(id, w1_max_slave_count, w1_max_slave_ttl, + &w1_master_driver, &w1_master_device); + if (!dev) { + mutex_unlock(&w1_mlock); return -ENOMEM; + } retval = w1_create_master_attributes(dev); - if (retval) + if (retval) { + mutex_unlock(&w1_mlock); goto err_out_free_dev; + } memcpy(dev->bus_master, master, sizeof(struct w1_bus_master)); @@ -144,10 +164,10 @@ int w1_add_master_device(struct w1_bus_master *master) dev_err(&dev->dev, "Failed to create new kernel thread. err=%d\n", retval); + mutex_unlock(&w1_mlock); goto err_out_rm_attr; } - mutex_lock(&w1_mlock); list_add(&dev->w1_master_entry, &w1_masters); mutex_unlock(&w1_mlock); -- 2.41.1