From 3089a4c8d3abc7e2ab105d1d39d415110d1566d6 Mon Sep 17 00:00:00 2001 From: Evgeny Boger Date: Thu, 23 Jan 2014 15:56:18 -0800 Subject: drivers/w1/masters/w1-gpio.c: add strong pullup emulation Strong pullup is emulated by driving pin logic high after write command when using tri-state push-pull GPIO. Signed-off-by: Evgeny Boger Cc: Greg KH Acked-by: David Fries Acked-by: Evgeniy Polyakov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/w1/w1_int.c | 12 ------------ 1 file changed, 12 deletions(-) (limited to 'drivers/w1/w1_int.c') diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c index 5a98649f6abc..590bd8a7cd1b 100644 --- a/drivers/w1/w1_int.c +++ b/drivers/w1/w1_int.c @@ -117,18 +117,6 @@ int w1_add_master_device(struct w1_bus_master *master) printk(KERN_ERR "w1_add_master_device: invalid function set\n"); return(-EINVAL); } - /* While it would be electrically possible to make a device that - * generated a strong pullup in bit bang mode, only hardware that - * controls 1-wire time frames are even expected to support a strong - * pullup. w1_io.c would need to support calling set_pullup before - * the last write_bit operation of a w1_write_8 which it currently - * doesn't. - */ - if (!master->write_byte && !master->touch_bit && master->set_pullup) { - printk(KERN_ERR "w1_add_master_device: set_pullup requires " - "write_byte or touch_bit, disabling\n"); - master->set_pullup = NULL; - } /* Lock until the device is added (or not) to w1_masters. */ mutex_lock(&w1_mlock); -- cgit v1.2.3