diff options
author | Jean-François Dagenais <dagenaisj@sonatest.com> | 2011-07-08 22:39:44 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-07-09 04:14:44 (GMT) |
commit | f607e7fc5fb94d92030c4527287e9c149ddf9e65 (patch) | |
tree | 49ac9020b87f028e947580425fef84222332fdf8 | |
parent | 453a9bf347f1e22a5bb3605ced43b2366921221d (diff) | |
download | linux-f607e7fc5fb94d92030c4527287e9c149ddf9e65.tar.xz |
w1: ds1wm: add a reset recovery parameter
This fixes a regression in 3.0 reported by Paul Parsons regarding the
removal of the msleep(1) in the ds1wm_reset() function:
: The linux-3.0-rc4 DS1WM 1-wire driver is logging "bus error, retrying"
: error messages on an HP iPAQ hx4700 PDA (XScale-PXA270):
:
: <snip>
: Driver for 1-wire Dallas network protocol.
: DS1WM w1 busmaster driver - (c) 2004 Szabolcs Gyurko
: 1-Wire driver for the DS2760 battery monitor chip - (c) 2004-2005, Szabolcs Gyurko
: ds1wm ds1wm: pass: 1 bus error, retrying
: ds1wm ds1wm: pass: 2 bus error, retrying
: ds1wm ds1wm: pass: 3 bus error, retrying
: ds1wm ds1wm: pass: 4 bus error, retrying
: ds1wm ds1wm: pass: 5 bus error, retrying
: ...
:
: The visible result is that the battery charging LED is erratic; sometimes
: it works, mostly it doesn't.
:
: The linux-2.6.39 DS1WM 1-wire driver worked OK. I haven't tried 3.0-rc1,
: 3.0-rc2, or 3.0-rc3.
This sleep should not be required on normal circuitry provided the
pull-ups on the bus are correctly adapted to the slaves. Unfortunately,
this is not always the case. The sleep is restored but as a parameter to
the probe function in the pdata.
[akpm@linux-foundation.org: coding-style fixes]
Reported-by: Paul Parsons <lost.distance@yahoo.com>
Tested-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Jean-François Dagenais <dagenaisj@sonatest.com>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | drivers/mfd/asic3.c | 1 | ||||
-rw-r--r-- | drivers/mfd/htc-pasic3.c | 1 | ||||
-rw-r--r-- | drivers/w1/masters/ds1wm.c | 5 | ||||
-rw-r--r-- | include/linux/mfd/ds1wm.h | 7 |
4 files changed, 14 insertions, 0 deletions
diff --git a/drivers/mfd/asic3.c b/drivers/mfd/asic3.c index c27fd1f..c71ae09 100644 --- a/drivers/mfd/asic3.c +++ b/drivers/mfd/asic3.c @@ -619,6 +619,7 @@ static void asic3_clk_disable(struct asic3 *asic, struct asic3_clk *clk) /* MFD cells (SPI, PWM, LED, DS1WM, MMC) */ static struct ds1wm_driver_data ds1wm_pdata = { .active_high = 1, + .reset_recover_delay = 1, }; static struct resource ds1wm_resources[] = { diff --git a/drivers/mfd/htc-pasic3.c b/drivers/mfd/htc-pasic3.c index 2808bd1..04c7093 100644 --- a/drivers/mfd/htc-pasic3.c +++ b/drivers/mfd/htc-pasic3.c @@ -99,6 +99,7 @@ static int ds1wm_disable(struct platform_device *pdev) static struct ds1wm_driver_data ds1wm_pdata = { .active_high = 0, + .reset_recover_delay = 1, }; static struct resource ds1wm_resources[] __initdata = { diff --git a/drivers/w1/masters/ds1wm.c b/drivers/w1/masters/ds1wm.c index ad57593..a0c8965 100644 --- a/drivers/w1/masters/ds1wm.c +++ b/drivers/w1/masters/ds1wm.c @@ -109,6 +109,7 @@ struct ds1wm_data { /* byte to write that makes all intr disabled, */ /* considering active_state (IAS) (optimization) */ u8 int_en_reg_none; + unsigned int reset_recover_delay; /* see ds1wm.h */ }; static inline void ds1wm_write_register(struct ds1wm_data *ds1wm_data, u32 reg, @@ -187,6 +188,9 @@ static int ds1wm_reset(struct ds1wm_data *ds1wm_data) return 1; } + if (ds1wm_data->reset_recover_delay) + msleep(ds1wm_data->reset_recover_delay); + return 0; } @@ -490,6 +494,7 @@ static int ds1wm_probe(struct platform_device *pdev) } ds1wm_data->irq = res->start; ds1wm_data->int_en_reg_none = (plat->active_high ? DS1WM_INTEN_IAS : 0); + ds1wm_data->reset_recover_delay = plat->reset_recover_delay; if (res->flags & IORESOURCE_IRQ_HIGHEDGE) irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_EDGE_RISING); diff --git a/include/linux/mfd/ds1wm.h b/include/linux/mfd/ds1wm.h index be469a3..38a372a 100644 --- a/include/linux/mfd/ds1wm.h +++ b/include/linux/mfd/ds1wm.h @@ -3,4 +3,11 @@ struct ds1wm_driver_data { int active_high; int clock_rate; + /* in milliseconds, the amount of time to */ + /* sleep following a reset pulse. Zero */ + /* should work if your bus devices recover*/ + /* time respects the 1-wire spec since the*/ + /* ds1wm implements the precise timings of*/ + /* a reset pulse/presence detect sequence.*/ + unsigned int reset_recover_delay; }; |