From be052cc87745e01846fb036eb81567c784439078 Mon Sep 17 00:00:00 2001 From: Roger Quadros Date: Tue, 7 Jul 2015 16:06:15 +0300 Subject: [PATCH] extcon: Fix hang and extcon_get/set_cable_state(). Users of find_cable_index_by_name() will cause a kernel hang as the while loop counter is never incremented and end condition is never reached. extcon_get_cable_state() and extcon_set_cable_state() are broken because they use cable index instead of cable id. This causes the first cable state (cable.0) to be always invalid in sysfs or extcon_get_cable_state() users. Introduce a new function find_cable_id_by_name() that fixes both of the above issues. Fixes: commit 73b6ecdb93e8 ("extcon: Redefine the unique id of supported external connectors without 'enum extcon' type") Cc: Greg Kroah-Hartman Signed-off-by: Roger Quadros Tested-by: Ivan T. Ivanov [cw00.choi: Fix minor coding style] Signed-off-by: Chanwoo Choi --- drivers/extcon/extcon.c | 46 ++++++++++++++++++++++++++++++----------- 1 file changed, 34 insertions(+), 12 deletions(-) diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c index 76157ab9faf3..0e2af1728965 100644 --- a/drivers/extcon/extcon.c +++ b/drivers/extcon/extcon.c @@ -124,25 +124,35 @@ static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id return -EINVAL; } -static int find_cable_index_by_name(struct extcon_dev *edev, const char *name) +static int find_cable_id_by_name(struct extcon_dev *edev, const char *name) { - unsigned int id = EXTCON_NONE; + unsigned int id = -EINVAL; int i = 0; - if (edev->max_supported == 0) - return -EINVAL; - - /* Find the the number of extcon cable */ + /* Find the id of extcon cable */ while (extcon_name[i]) { if (!strncmp(extcon_name[i], name, CABLE_NAME_MAX)) { id = i; break; } + i++; } - if (id == EXTCON_NONE) + return id; +} + +static int find_cable_index_by_name(struct extcon_dev *edev, const char *name) +{ + unsigned int id; + + if (edev->max_supported == 0) return -EINVAL; + /* Find the the number of extcon cable */ + id = find_cable_id_by_name(edev, name); + if (id < 0) + return id; + return find_cable_index_by_id(edev, id); } @@ -228,9 +238,11 @@ static ssize_t cable_state_show(struct device *dev, struct extcon_cable *cable = container_of(attr, struct extcon_cable, attr_state); + int i = cable->cable_index; + return sprintf(buf, "%d\n", extcon_get_cable_state_(cable->edev, - cable->cable_index)); + cable->edev->supported_cable[i])); } /** @@ -361,8 +373,13 @@ EXPORT_SYMBOL_GPL(extcon_get_cable_state_); */ int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name) { - return extcon_get_cable_state_(edev, find_cable_index_by_name - (edev, cable_name)); + unsigned int id; + + id = find_cable_id_by_name(edev, cable_name); + if (id < 0) + return id; + + return extcon_get_cable_state_(edev, id); } EXPORT_SYMBOL_GPL(extcon_get_cable_state); @@ -404,8 +421,13 @@ EXPORT_SYMBOL_GPL(extcon_set_cable_state_); int extcon_set_cable_state(struct extcon_dev *edev, const char *cable_name, bool cable_state) { - return extcon_set_cable_state_(edev, find_cable_index_by_name - (edev, cable_name), cable_state); + unsigned int id; + + id = find_cable_id_by_name(edev, cable_name); + if (id < 0) + return id; + + return extcon_set_cable_state_(edev, id, cable_state); } EXPORT_SYMBOL_GPL(extcon_set_cable_state); -- 2.39.5