Fix scll/sclh calculations for HS and fast modes. Currently the driver
uses equal (roughly) low/high times which will result in too short
low time.
OMAP3430 TRM gives the following equations:
F/S: tLow = (scll + 7) * internal_clk
tHigh = (sclh + 5) * internal_clk
HS: tLow = (scll + 7) * fclk
tHigh = (sclh + 5) * fclk
Furthermore, the I2C specification sets the following minimum values
for HS tLow/tHigh for capacitive bus loads 100 pF (maximum speed 3400)
and 400 pF (maximum speed 1700):
speed tLow tHigh
3400 160 ns 60 ns
1700 320 ns 120 ns
and for F/S:
speed tLow tHigh
400 1300 ns 600 ns
100 4700 ns 4000 ns
By using duty cycles 33/66 (HS, F) and 50/50 (S) we stay above these
minimum values.
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
By providing a dummy ick for OMAP1510 and OMAP310, we avoid having
SoC conditional clock information in i2c-omap.c. Also, fix the
error handling by making sure we propagate the error returned via
clk_get().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On OMAP1, the I2C functional clock (fck) is the armxor_ck, so there's
no need to get "armxor_ck" separately.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The probe function used a pointer to the interrupt
handler to register as a 'void *', change it to the
proper type of irq_handler_t.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
I2C_WE registers were not configured, which caused huge delays in
I2C operations while cpu idle was enabled and omap entered WFI.
This patch enables all I2C wakeup sources.
Signed-off-by: Kalle Jokiniemi <ext-kalle.jokiniemi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The I2C controller clears its OCP_SYSCONFIG register after an OCP soft reset.
Reprogram OCP_SYSCONFIG for maximum power savings on rev3.6 controllers
and beyond. On 2430, this involves setting the module AUTOIDLE bit.
On 3430, this includes module AUTOIDLE, wakeup enable, slave smart-idle,
and considers only the module functional clock state for idle-ack.
Boot-tested on 2430SDP and 3430SDP.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
i2c-omap discriminates only between "revision 1" or "greater than
revision 1." A following patch introduces code that must also
discriminate between rev2.x, rev3.6, and rev3.12 controllers. Support
this by storing the full revision data from the I2C_REV register, rather
than just a single bit.
The revision definitions may need to be extended for other ES levels
that aren't currently available here. rev3.6 is what's present on the
2430SDP here (unknown ES revision); rev3.12 is used on the 3430ES2
here.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
omap_i2c_unidle() and omap_i2c_idle() are called recursively during
omap_i2c_probe(). This is evidently unexpected and will wipe
out the I2C interrupt enable register the second time that
omap_i2c_idle() is called consecutively. Any I2C transactions
following a probe of a bus with at least one device on it will then
time out.
Fix by moving omap_i2c_idle() further up in omap_i2c_probe(). Ensure
the I2C controller is marked as idle before the probe starts. Also
attempt to catch future reappearances of this bug early in development
by warning in omap_i2c_{un,}idle() when they are called recursively.
Problem reported by David Brownell <david-b@pacbell.net>.
Tested on 3430SDP and 2430SDP.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Acked-by; Steve Sakoman <steve@sakoman.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Skip compiling OMAP15xx I2C ISR for non-OMAP15xx builds. Saves 400 bytes
of text for most OMAP builds.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Based on an earlier patch from Nishant Menon:
- Transfers can use FIFO on FIFO capable devices
- Prevents errors for HSI2C if FIFO is not used
- Implemented errenous handling of STT-STP handling on SDP2430
Also merged in is a fix from Jaron Marini to fix occasional i2c
hang if OMAP_I2C_CON_STT remains asserted.
Signed-off-by: Jason P Marini <jason.marini@gmail.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Omap2430 has additional support for high-speed I2C.
This patch moves I2C speed parameter (from module) to platform data.
Also added basic High Speed support based on I2C bus speed.
This patch is tested for high speed I2C (with TWL4030 Keypad) and works as
expected.
Also change the 2430 i2chs_fck names to use the standard naming.
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Syed Mohammed Khasim <x0khasim@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
omap_i2c_idle() sets an internal flag, "dev->idle", instructing its
ISR to decline interrupts. It sets this flag before it actually masks
the interrupts on the I2C controller. This is problematic, since an
I2C interrupt could arrive after dev->idle is set, but before the
interrupt source is masked. When this happens, Linux disables the I2C
controller's IRQ, causing all future transactions on the bus to fail.
Symptoms, happening on about 7% of boots:
irq 56: nobody cared (try booting with the "irqpoll" option)
<warning traceback here>
Disabling IRQ #56
i2c_omap i2c_omap.1: controller timed out
In omap_i2c_idle(), this patch sets dev->idle only after the interrupt
mask write to the I2C controller has left the ARM write buffer.
That's probably the major offender. For additional prophylaxis, in
omap_i2c_unidle(), the patch clears the dev->idle flag before
interrupts are enabled, rather than afterwards.
The patch has survived twenty-two reboots on the 3430SDP here without
wedging I2C1. Not absolutely dispositive, but promising!
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
If there is a signal pending and wait_for_completion_interruptible_timeout
terminates with -ERESTARTSYS, we return and disable the i2c clocks in
omap_i2c_xfer.
If we terminate before sending last i2c message with a stop condition, the
bus remains busy and we are not able to send new messages into bus with
successive omap_i2c_xfer calls. Therefore a pending signal is not caught
here and we return only because of timeout or i2c error.
Signed-off-by: Jarkko Nikula <jarkko.nikula@nokia.com>
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Since 43cc71eed1, the platform
modalias is prefixed with "platform:". Add MODULE_ALIAS() to the
hotpluggable I2C platform drivers, to allow module auto loading.
[ db: add some more drivers ]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
If an I2C interrupt happens between disabling interface clock
and functional clock, the interrupt handler will produce an
external abort on non-linefetch error when trying to access
driver registers while interface clock is disabled.
This patch fixes the problem by saving and disabling i2c-omap
interrupt before turning off the clocks. Also disable functional
clock before the interface clock as suggested by Paul Walmsley.
Patch also renames enable/disable_clocks functions to unidle/idle
functions. Note that the driver is currently not taking advantage
of the idle interrupts. To use the idle interrupts, driver would
have to enable interface clock based on the idle interrupt
and dev->idle flag.
This patch has been tested in linux-omap tree with various omaps.
Cc: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
I2C adapter drivers are supposed to handle retries on nack by themselves
if they do, so there's no point in setting .retries if they don't.
As this retry mechanism is going away (at least in its current form),
clean this up now so that we don't get build failures later.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This patch fixes bug #9581 reported by Marcio Buss. If kzalloc fails,
omap_i2c_write_reg() tries to reset an unallocated I2C controller.
Cc: Marcio Buss <marciobuss@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
* Convert files to UTF-8.
* Also correct some people's names
(one example is Eißfeldt, which was found in a source file.
Given that the author used an ß at all in a source file
indicates that the real name has in fact a 'ß' and not an 'ss',
which is commonly used as a substitute for 'ß' when limited to
7bit.)
* Correct town names (Goettingen -> Göttingen)
* Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313)
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Update the OMAP I2C driver to use i2c_add_numbered_adapter(), so that
later patches can convert boards to using new-style drivers.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
i2c: Constify i2c_algorithm declarations, part 2
Make struct i2c_algorithm declarations const in all i2c bus drivers
where it is possible.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c: New bus driver for TI OMAP boards
This patch adds I2C bus driver for various Texas
Instruments (TI) OMAP1/2 (http://www.ti.com/omap) series
based boards like OMAP1510/1610/1710/242x.
Signed-off-by: Komal Shah <komal_shah802003@yahoo.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Aaro Koskinen