Under certain conditions, the mv64xxx I2C bus can hang preventing
further operation. To make the driver more robust, we now reset
the I2C hardware and the driver state machine when such hangs are
detected.
Signed-off-by: Dale Farnsworth <dale@farnsworth.org>
Acked-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Convert the Marvell mv64xxx I2C driver to use the new i2c infrastructure,
by calling i2c_add_numbered_adapter(). This allows clients to be
registered before the bus is instantiated.
Signed-off-by: Dale Farnsworth <dale@farnsworth.org>
Acked-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This shrinks the size of "struct i2c_client" by 40 bytes:
- Substantially shrinks the string used to identify the chip type
- The "flags" don't need to be so big
- Removes some internal padding
It also adds kerneldoc for that struct, explaining how "name" is really a
chip type identifier; it's otherwise potentially confusing.
Because the I2C_NAME_SIZE symbol was abused for both i2c_client.name
and for i2c_adapter.name, this needed to affect i2c_adapter too. The
adapters which used that symbol now use the more-obviously-correct
idiom of taking the size of that field.
JD: Shorten i2c_adapter.name from 50 to 48 bytes while we're here, to
avoid wasting space in padding.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Declare the parent device of i2c_adapter devices each time we can
easily do so. It makes the i2c_adapter appear at the right place in
the device tree, rather than as a platform device.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Cc: Jody McIntyre <scjody@modernduck.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: v4l-dvb-maintainer@linuxtv.org
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
I have a Marvell board which has the same i2c hw block than mv64xxx, so
I'm trying to use i2c-mv64xxx driver.
But I get the following random oops at boot:
Unable to handle kernel NULL pointer dereference at virtual address 00000002
Backtrace:
[<c0397e4c>] (mv64xxx_i2c_intr+0x0/0x2b8) from [<c02879c4>] (__do_irq+0x4c/0x8c)
[<c0287978>] (__do_irq+0x0/0x8c) from [<c0287c0c>] (do_level_IRQ+0x68/0xc0)
r8 = C0501E08 r7 = 00000005 r6 = C0501E08 r5 = 00000005
r4 = C048BB78
[<c0287ba4>] (do_level_IRQ+0x0/0xc0) from [<c02885f8>] (asm_do_IRQ+0x50/0x134)
r6 = C0449C78 r5 = F1020000 r4 = FFFFFFFF
[<c02885a8>] (asm_do_IRQ+0x0/0x134) from [<c02869c4>] (__irq_svc+0x24/0x100)
r8 = C1CAC400 r7 = 00000005 r6 = 00000002 r5 = F1020000
r4 = FFFFFFFF
[<c0287efc>] (setup_irq+0x0/0x124) from [<c02880d0>] (request_irq+0xb0/0xd0)
r7 = C041B2AC r6 = C0397E4C r5 = 00000000 r4 = 00000005
[<c0288020>] (request_irq+0x0/0xd0) from [<c03985f4>] (mv64xxx_i2c_probe+0x148/0x244)
[<c03984ac>] (mv64xxx_i2c_probe+0x0/0x244) from [<c038bedc>] (platform_drv_probe+0x20/0x24)
The oops is caused by a spurious interrupt that occurs when request_irq
is called. mv64xxx_i2c_fsm() tries to read drv_data->msg, which is NULL.
I noticed that hardware init is done after requesting irq. Thus any
pending irq from previous hardware usage may cause this.
The following patch fixes it:
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Acked-by: Mark A. Greer <mgreer@mvista.com>
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>
platform_get_irq*() now returns on -ENXIO when the resource cannot be
found. Ensure all users of platform_get_irq*() handle this error
appropriately.
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When the i2c-mv64xxx i2c driver is signalled to abort a transaction,
it aborts it immediately by issuing a stop condition on the bus.
This violates the i2c protocol and can cause what appears to be an i2c
bus hang. This patch delays issuing the stop condition until the i2c
device can reasonably expect a stop condition.
Also includes a minor fixup.
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The busses/i2c-mv64xxx.c driver doesn't currently compile because of an
incorrect argument to dev_err(). This patch fixes that.
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
Use kzalloc instead of kmalloc+memset in all remaining i2c bus and
chip drivers.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch updates the .owner field for various struct xxxx_driver variables,
other than pci_driver.
Signed-off-by: Laurent Riffard <laurent.riffard@free.fr>
Signed-off-by: Jean Delvare <khali@linux-fr>
Acked-by: Mark A. Greer <mgreer@mvista.com>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Acked-by: Deepak Saxena <dsaxena@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When an i2c transfer is successful, an incorrect value is returned.
This patch fixes that.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Merge the algorithm id part (16 upper bits) of the i2c adapters ids
into the definition of the adapters ids directly. After that, we don't
need to OR both ids together for each i2c_adapter structure.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There are no more users of i2c_algorithm.id, so we can finally drop
this structure member.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The name member of the i2c_algorithm is never used, although all
drivers conscientiously fill it. We can drop it completely, this
structure doesn't need to have a name.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
