Add polling I2C transfer implementation for PXA I2C. This is needed
for cases where I2C transactions have to occur at times interrups are
disabled.
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Acked-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
remove #ifdef CONFIG_PXA27x .. #endif and use cpu_is_pxaXXXX() macros
so that a single binary can support PXA25x/PXA27x/PXA3xx at run-time.
Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
i2c-pxa, rename BIT macro to PXA_BIT
BIT macro will be global definiton of (1 << x)
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Nicolas Pitre <nico@cam.org>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turns out that platform_device.id is a "u32" so testing it for being
nonnegative is useless when setting up an i2c adapte. Instead,
do what the platform_bus code does and test it against the value "-1".
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Using lockdep validator causes warnings like
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
[<c00241a0>] (dump_stack+0x0/0x14) from [<c00520f8>] (__lock_acquire+0x150/0xc40)
[<c0051fa8>] (__lock_acquire+0x0/0xc40) from [<c00530a0>] (lock_acquire+0x5c/0x70)
[<c0053044>] (lock_acquire+0x0/0x70) from [<c01d9e44>] (_spin_lock_irq+0x48/0x58)
r7:c07e5144 r6:00000000 r5:c015fb94 r4:c07e50b8
[<c01d9dfc>] (_spin_lock_irq+0x0/0x58) from [<c015fb94>] (i2c_pxa_xfer+0x110/0x2e0)
r5:c07e50b8 r4:0000001f
This is caused by memcpy'ing a statical initialized spin-lock. This patch
removes a static pxa_i2c structure which was used only as a source for this
memcpy() operation. Instead of, members and the spinlock will be
initialized manually.
Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
From commit 7d054817b7:
> According to the PXA27x developer's manual, we shall do so.
We shall also at least compile test our changes.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It was reported to me that the i2c-pxa driver was not able to process
more that 50 transactions per second. Investigation revealed that the
I2C unit was busy for 20 ms after every transaction. The reason seems
to be that we forget to clear the STOP and ACKNACK bits at the end of
the transaction. According to the PXA27x developer's manual, we shall
do so.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Nicolas Pitre <nico@cam.org>
This patch removes the unnecessary bit number from CKENnn_XXXX
definitions for PXA, so that
CKEN0_PWM0 --> CKEN_PWM0
CKEN1_PWM1 --> CKEN_PWM1
...
CKEN24_CAMERA --> CKEN_CAMERA
The reasons for the change of these defitions are:
1. they do not scale - they are currently valid for pxa2xx, but
definitely not valid for pxa3xx, e.g., pxa3xx has bit 3 for camera
instead of bit 24
2. they are unnecessary - the peripheral name within the definition
has already announced its usage, we don't need those bit numbers
to know which peripheral we are going to enable/disable clock for
3. they are inconvenient - think about this: a driver programmer
for pxa has to remember which bit in the CKEN register to turn
on/off
Another change in the patch is to make the definitions equal to its
clock bit index, so that
#define CKEN_CAMERA (24)
instead of
#define CKEN_CAMERA (1 << 24)
this change, however, will add a run-time bit shift operation in
pxa_set_cken(), but the benefit of this change is that it scales
when bit index exceeds 32, e.g., pxa3xx has two registers CKENA
and CKENB, totally 64 bit for this, suppose CAMERA clock enabling
bit is CKENB:10, one can simply define CKEN_CAMERA to be (32 + 10)
and so that pxa_set_cken() need minimum change to adapt to that.
Signed-off-by: eric miao <eric.y.miao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reposted patch for kernel 2.6.21-rc2.
The driver i2c-pxa doesn't set the class member in i2c_adapter, which
is used to register the I2C adapter. The hwmon (sensors) drivers (e.g.
adm1021) that are connected to a i2c-pxa adapter don't attach because
they expect that the adapter supports class I2C_CLASS_HWMON.
This patch adds functionality to allow platforms to set the class and
pass it as platform_data to the i2c-pxa driver. Sample usage in
platform code:
static struct i2c_pxa_platform_data my_i2c_platform_data = {
.class = I2C_CLASS_HWMON
};
static void __init my_platform_init(void)
{
(void) platform_add_devices(devices, ARRAY_SIZE(devices));
pxa_set_i2c_info(&my_i2c_platform_data);
}
Signed-off-by: Matej Kenda <matej.kenda@hermes-softlab.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Switch the i2c-pxa driver to actually using the platform device information and let it handle the power i2c bus on pxa27x too. Original version of this patch didn't compile with CONFIG_I2C_PXA_SLAVE set.
Signed-off-by: G. Liakhovetski <gl@dsa-ac.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The i2c-pxa driver should not contain EEPROM slave-mode emulation;
this is something the platform should provide where required. Remove
it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
i2c-pxa times out when trying to enable slave mode due to an
incorrect test. Also, check that i2c->slave is non-NULL
before dereferencing it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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>
Cleanup after the semaphores to mutexes conversions in the i2c
subsystem.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]). Some trailing
whitespaces are also removed.
Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch from Richard Purdie
This patch adds a check to see if the pxa i2c interface is enabled
before allowing it to be used and resets it if found to be disabled.
This automatically restores the interface if the device has been
suspended and resumed without causing any suspend/resume call ordering
issues.
The patch also fixes a build warning and adds an appropriate module
licence (the module is gpl according to the header).
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows us to eliminate the casts in the drivers, and eventually
remove the use of the device_driver function pointer methods for
platform device drivers.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Convert everyone who uses platform_bus_type to include
linux/platform_device.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>