Move out code related to device-tree parsing from the probe function into
tegra_i2c_parse_dt() in order to make code more consistent.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Use clk-bulk helpers and factor out clocks initialization into separate
function in order to make code cleaner.
The clocks initialization now performed after reset-control initialization
in order to avoid a noisy -PROBE_DEFER errors on T186+ from the clk-bulk
helper which doesn't silence this error code. Hence reset_control_get()
now may return -EPROBE_DEFER on newer Tegra SoCs because they use BPMP
driver that provides reset controls and BPMP doesn't come up early during
boot. Previously rst was protected by the clocks retrieval and now this
patch makes dev_err_probe() to be used for the rst error handling.
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Use common helper for retrieval of the interrupt number in order to make
code cleaner. Note that platform_get_irq() prints error message by itself.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Driver now uses devm_platform_get_and_ioremap_resource() which replaces
the typical boilerplate code and makes code cleaner.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Use a single reset_control_reset() instead of assert/deasset couple in
order to make code cleaner a tad. Note that the reset_control_reset()
uses 1 microsecond delay instead of 2 that was used previously, but this
shouldn't matter because one microsecond is a default reset time for most
of Tegra peripherals and TRM doesn't mention anything special in regards
to I2C controller's reset propagation time.
In addition don't ignore potential error of the reset control by emitting
a noisy warning if it fails, which will indicate an existence of a severe
problem, while still allow machine to boot up.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The error message prints number of vIRQ, which isn't a useful information.
In practice devm_request_irq() never fails, hence let's remove the bogus
message in order to make code cleaner.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The runtime PM is guaranteed to be always available on Tegra after commit
40b2bb1b13 ("ARM: tegra: enforce PM requirement"). Hence let's remove
all the RPM-availability checking and handling from the code.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The "non_hs_mode" divisor value is fixed, thus there is no need to have
the variable i2c_dev.clk_divisor_non_hs_mode struct member. Let's remove
it and move the mode selection into tegra_i2c_init() where it can be
united with the timing selection.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
It doesn't make sense to conditionalize the div-clk rate changes because
rate is fixed and it won't ever change once it's set at the driver's probe
time. All further changes are NO-OPs because CCF caches rate and skips
rate-change if rate is unchanged.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The tegra_i2c_issue_bus_clear() may fail and in this case BUS_CLR_DONE
stays unmasked. Hence let's mask it for consistency. This patch doesn't
fix any known problems.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Technically the tegra_i2c_flush_fifos() may fail and transfer should be
aborted in this case, but this shouldn't ever happen in practice unless
there is a bug somewhere in the driver. Let's add the error check just
for completeness.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The pm_runtime_get_sync() always bumps refcount regardless of whether it
succeeds or fails. Hence driver is responsible for restoring of the RPM
refcounting. This patch adds missing RPM puts which restore refcounting
in a case of pm_runtime_get_sync() error.
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The tegra_i2c_flush_fifos() shouldn't sleep in atomic transfer and jiffies
are not updating if interrupts are disabled. Let's switch to use iopoll
API helpers for register-polling. The iopoll API provides helpers for both
atomic and non-atomic cases.
Note that this patch doesn't fix any known problem because normally FIFO
is flushed at the time of starting a new transfer.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
VI I2C is on host1x bus so APB DMA can't be used for Tegra210 VI
I2C and there are no tx and rx dma channels for VI I2C.
So, avoid attempt of requesting DMA channels.
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
VI I2C is on host1x bus and is part of VE power domain.
During suspend/resume VE power domain goes through power off/on.
So, controller reset followed by i2c re-initialization is required
after the domain power up.
This patch fixes it.
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
tegra_i2c_runtime_resume does not disable prior enabled clocks
properly.
This patch fixes it.
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
clk_enable, clk_disable, clk_prepare, and clk_unprepare APIs have
implementation for checking clk pointer not NULL and clock consumers
can safely call these APIs without NULL pointer check.
So, this patch cleans up Tegra i2c driver to remove explicit checks
before these APIs.
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Tegra VI I2C is part of VE power domain and typically used for
camera usecases.
VE power domain is not always on and is non-IRQ safe. So, IRQ safe
device cannot be attached to a non-IRQ safe domain as it prevents
powering off the PM domain and generic power domain driver will warn.
Current driver marks all I2C devices as IRQ safe and VI I2C device
does not require IRQ safe as it will not be used for atomic transfers.
This patch has fix to make VI I2C as non-IRQ safe.
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Tegra210 has an extra instance of the I2C controller that is in the
domain of host1x and usually used for camera use-cases. The programming
model for the VI variant of the controller is roughly the same as for
the other variants, except that the I2C registers start at an offset
and are spaced further apart. VI I2C also doesn't support slave mode.
Signed-off-by: Thierry Reding <treding@nvidia.com>
DMA transfer could be completed, but CPU (which handles DMA interrupt)
may get too busy and can't handle the interrupt in a timely manner,
despite of DMA IRQ being raised. In this case the DMA state needs to
synchronized before terminating DMA transfer in order not to miss the
DMA transfer completion.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Boot CPU0 always handle I2C interrupt and under some rare circumstances
(like running KASAN + NFS root) it may stuck in uninterruptible state for
a significant time. In this case we will get timeout if I2C transfer is
running on a sibling CPU, despite of IRQ being raised. In order to handle
this rare condition, the IRQ status needs to be checked after completion
timeout.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
One of the I2C controllers on Tegra SoCs is typically connected to a
system PMIC, which provides controls for critical power supplies for
most platforms.
Some drivers, such as PCI, need to disable these regulators during a
very late stage during suspend and resume them at a very early stage
during resume.
To support these use-cases, keep interrupts disabled during suspend/
resume.
Suggested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Depending on the board design, the I2C controllers found on Tegra SoCs
may require pinmuxing in order to function. This is done as part of the
driver's runtime suspend/resume operations. However, the PM core does
not allow devices to go into runtime suspend during system sleep to
avoid potential races with the suspend/resume of their parents.
As a result of this, when Tegra SoCs resume from system suspend, their
I2C controllers may have lost the pinmux state in hardware, whereas the
pinctrl subsystem is not aware of this. To fix this, make sure that if
the I2C controller is not runtime suspended, the runtime suspend code is
still executed in order to disable the module clock (which we don't need
to be enabled during sleep) and set the pinmux to the idle state.
Conversely, make sure that the I2C controller is properly resumed when
waking up from sleep so that pinmux settings are properly restored.
This fixes a bug seen with DDC transactions to an HDMI monitor timing
out when resuming from system suspend.
Signed-off-by: Thierry Reding <treding@nvidia.com>
This reverts commit 9f42de8d4e.
It's not safe to use pm_runtime_force_{suspend,resume}(), especially
during the noirq phase of suspend. See also the guidance provided in
commit 1e2ef05bb8 ("PM: Limit race conditions between runtime PM
and system sleep (v2)").
Signed-off-by: Thierry Reding <treding@nvidia.com>
DMA transfer could be completed, but CPU (which handles DMA interrupt)
may get too busy and can't handle the interrupt in a timely manner,
despite of DMA IRQ being raised. In this case the DMA state needs to
synchronized before terminating DMA transfer in order not to miss the
DMA transfer completion.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Boot CPU0 always handle I2C interrupt and under some rare circumstances
(like running KASAN + NFS root) it may stuck in uninterruptible state for
a significant time. In this case we will get timeout if I2C transfer is
running on a sibling CPU, despite of IRQ being raised. In order to handle
this rare condition, the IRQ status needs to be checked after completion
timeout.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
It is more robust to check completion status in addition to the left time
in a case of DMA transfer because transfer's completion happens in two
phases [one is ISR, other is tasklet] and thus it is possible that DMA is
completed while I2C completion awaiting times out because of the deferred
notification done by the DMA driver. The DMA completion status becomes
100% actual after DMA synchronization. This fixes spurious DMA timeouts
when system is under load.
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
It is possible that I2C could error out in the middle of DMA transfer and
in this case DMA channel needs to be reset, otherwise a follow up transfer
will fail because DMA channel stays blocked.
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There is nothing to synchronize in regards to memory accesses for PIO
transfers and for DMA transfers the DMA API takes care of the syncing.
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
DMA is preferred for a larger transfers, while PIO is preferred for a
smaller transfers to avoid unnecessary DMA overhead. There is no strict
size limitations for the PIO-mode transfers, so let's rename the constant
for clarity.
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
System shutdown may happen with interrupts being disabled and in this case
kernel may hang if atomic transfer isn't supported by driver.
There were several occurrences where I found my Nexus 7 completely
discharged despite of being turned off and then one day I spotted this in
the log:
reboot: Power down
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/i2c/i2c-core.h:40 i2c_transfer+0x95/0x9c
No atomic I2C transfer handler for 'i2c-1'
Modules linked in: tegra30_devfreq
CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted 5.4.0-next-20191202-00120-gf7ecd80fb803-dirty #3195
Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
[<c010e4b5>] (unwind_backtrace) from [<c010a0fd>] (show_stack+0x11/0x14)
[<c010a0fd>] (show_stack) from [<c09995e5>] (dump_stack+0x85/0x94)
[<c09995e5>] (dump_stack) from [<c011f3d1>] (__warn+0xc1/0xc4)
[<c011f3d1>] (__warn) from [<c011f691>] (warn_slowpath_fmt+0x61/0x78)
[<c011f691>] (warn_slowpath_fmt) from [<c069a8dd>] (i2c_transfer+0x95/0x9c)
[<c069a8dd>] (i2c_transfer) from [<c05667f1>] (regmap_i2c_read+0x4d/0x6c)
[<c05667f1>] (regmap_i2c_read) from [<c0563601>] (_regmap_raw_read+0x99/0x1cc)
[<c0563601>] (_regmap_raw_read) from [<c0563757>] (_regmap_bus_read+0x23/0x38)
[<c0563757>] (_regmap_bus_read) from [<c056293d>] (_regmap_read+0x3d/0xfc)
[<c056293d>] (_regmap_read) from [<c0562d3b>] (_regmap_update_bits+0x87/0xc4)
[<c0562d3b>] (_regmap_update_bits) from [<c0563add>] (regmap_update_bits_base+0x39/0x50)
[<c0563add>] (regmap_update_bits_base) from [<c056fd39>] (max77620_pm_power_off+0x29/0x2c)
[<c056fd39>] (max77620_pm_power_off) from [<c013bbdd>] (__do_sys_reboot+0xe9/0x170)
[<c013bbdd>] (__do_sys_reboot) from [<c0101001>] (ret_fast_syscall+0x1/0x28)
Exception stack(0xde907fa8 to 0xde907ff0)
7fa0: 00000000 00000000 fee1dead 28121969 4321fedc 00000000
7fc0: 00000000 00000000 00000000 00000058 00000000 00000000 00000000 00000000
7fe0: 0045adf0 bed9abb8 004444a0 b6c666d0
---[ end trace bdd18f87595b1a5e ]---
The atomic transferring is implemented by enforcing PIO mode for the
transfer and by polling interrupt status until transfer is completed or
failed.
Now system shuts down properly every time.
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Potentially it is possible that interrupt may fire after transfer timeout.
That may not end up well for the next transfer because interrupt handling
may race with hardware resetting.
This is very unlikely to happen in practice, but anyway let's prevent the
potential problem by enabling interrupt only at the moments when it is
actually necessary to get some interrupt event.
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
One of the recent Tegra I2C commits made a change that resumes runtime PM
during driver's probe, but it missed to put the RPM in a case of error.
Note that it's not correct to use pm_runtime_status_suspended because it
breaks RPM refcounting.
Fixes: 8ebf15e9c8 ("i2c: tegra: Move suspend handling to NOIRQ phase")
Cc: <stable@vger.kernel.org> # v5.4+
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I noticed that sometime I2C clock is kept enabled during suspend-resume.
This happens because runtime PM defers dynamic suspension and thus it may
happen that runtime PM is in active state when system enters into suspend.
In particular I2C controller that is used for CPU's DVFS is often kept ON
during suspend because CPU's voltage scaling happens quite often.
Fixes: 8ebf15e9c8 ("i2c: tegra: Move suspend handling to NOIRQ phase")
Cc: <stable@vger.kernel.org> # v5.4+
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Commit acc8abcb2a ("i2c: tegra: Add suspend-resume support") added
suspend support for the Tegra I2C driver and following this change on
Tegra30 the following WARNING is seen on entering suspend ...
WARNING: CPU: 2 PID: 689 at /dvs/git/dirty/git-master_l4t-upstream/kernel/drivers/i2c/i2c-core.h:54 __i2c_transfer+0x35c/0x70c
i2c i2c-4: Transfer while suspended
Modules linked in: brcmfmac brcmutil
CPU: 2 PID: 689 Comm: rtcwake Not tainted 5.3.0-rc7-g089cf7f6ecb2 #1
Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
[<c0112264>] (unwind_backtrace) from [<c010ca94>] (show_stack+0x10/0x14)
[<c010ca94>] (show_stack) from [<c0a77024>] (dump_stack+0xb4/0xc8)
[<c0a77024>] (dump_stack) from [<c0124198>] (__warn+0xe0/0xf8)
[<c0124198>] (__warn) from [<c01241f8>] (warn_slowpath_fmt+0x48/0x6c)
[<c01241f8>] (warn_slowpath_fmt) from [<c06f6c40>] (__i2c_transfer+0x35c/0x70c)
[<c06f6c40>] (__i2c_transfer) from [<c06f7048>] (i2c_transfer+0x58/0xf4)
[<c06f7048>] (i2c_transfer) from [<c06f7130>] (i2c_transfer_buffer_flags+0x4c/0x70)
[<c06f7130>] (i2c_transfer_buffer_flags) from [<c05bee78>] (regmap_i2c_write+0x14/0x30)
[<c05bee78>] (regmap_i2c_write) from [<c05b9cac>] (_regmap_raw_write_impl+0x35c/0x868)
[<c05b9cac>] (_regmap_raw_write_impl) from [<c05b984c>] (_regmap_update_bits+0xe4/0xec)
[<c05b984c>] (_regmap_update_bits) from [<c05bad04>] (regmap_update_bits_base+0x50/0x74)
[<c05bad04>] (regmap_update_bits_base) from [<c04d453c>] (regulator_disable_regmap+0x44/0x54)
[<c04d453c>] (regulator_disable_regmap) from [<c04cf9d4>] (_regulator_do_disable+0xf8/0x268)
[<c04cf9d4>] (_regulator_do_disable) from [<c04d1694>] (_regulator_disable+0xf4/0x19c)
[<c04d1694>] (_regulator_disable) from [<c04d1770>] (regulator_disable+0x34/0x64)
[<c04d1770>] (regulator_disable) from [<c04d2310>] (regulator_bulk_disable+0x28/0xb4)
[<c04d2310>] (regulator_bulk_disable) from [<c0495cd4>] (tegra_pcie_power_off+0x64/0xa8)
[<c0495cd4>] (tegra_pcie_power_off) from [<c0495f74>] (tegra_pcie_pm_suspend+0x25c/0x3f4)
[<c0495f74>] (tegra_pcie_pm_suspend) from [<c05af48c>] (dpm_run_callback+0x38/0x1d4)
[<c05af48c>] (dpm_run_callback) from [<c05afe30>] (__device_suspend_noirq+0xc0/0x2b8)
[<c05afe30>] (__device_suspend_noirq) from [<c05b1c24>] (dpm_noirq_suspend_devices+0x100/0x37c)
[<c05b1c24>] (dpm_noirq_suspend_devices) from [<c05b1ebc>] (dpm_suspend_noirq+0x1c/0x48)
[<c05b1ebc>] (dpm_suspend_noirq) from [<c017d2c0>] (suspend_devices_and_enter+0x1d0/0xa00)
[<c017d2c0>] (suspend_devices_and_enter) from [<c017dd10>] (pm_suspend+0x220/0x74c)
[<c017dd10>] (pm_suspend) from [<c017c2c8>] (state_store+0x6c/0xc8)
[<c017c2c8>] (state_store) from [<c02ef398>] (kernfs_fop_write+0xe8/0x1c4)
[<c02ef398>] (kernfs_fop_write) from [<c0271e38>] (__vfs_write+0x2c/0x1c4)
[<c0271e38>] (__vfs_write) from [<c02748dc>] (vfs_write+0xa4/0x184)
[<c02748dc>] (vfs_write) from [<c0274b7c>] (ksys_write+0x9c/0xdc)
[<c0274b7c>] (ksys_write) from [<c0101000>] (ret_fast_syscall+0x0/0x54)
Exception stack(0xe9f21fa8 to 0xe9f21ff0)
1fa0: 0000006c 004b2438 00000004 004b2438 00000004 00000000
1fc0: 0000006c 004b2438 004b1228 00000004 00000004 00000004 0049e78c 004b1228
1fe0: 00000004 be9809b8 b6f0bc0b b6e96206
The problem is that the Tegra PCIe driver indirectly uses I2C for
controlling some regulators and the I2C driver is now being suspended
before the PCIe driver causing the PCIe suspend to fail. The Tegra PCIe
driver is suspended during the NOIRQ phase and this cannot be changed
due to other dependencies. Therefore, we also need to move the suspend
handling for the Tegra I2C driver to the NOIRQ phase as well.
In order to move the I2C suspend handling to the NOIRQ phase we also
need to avoid calling pm_runtime_get/put() because per commit
1e2ef05bb8 ("PM: Limit race conditions between runtime PM and system
sleep (v2)") these cannot be called early in resume. The function
tegra_i2c_init(), called during resume, calls pm_runtime_get/put() and
so move these calls outside of tegra_i2c_init(), so this function can
be used during the NOIRQ resume phase.
Fixes: acc8abcb2a ("i2c: tegra: Add suspend-resume support")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The I2C driver fails to probe if CONFIG_PM_SLEEP=n because runtime PM
doesn't depend on the PM sleep and in this case the runtime PM ops are
not included in the driver, resulting in I2C clock not being enabled.
It's much cleaner to simply allow compiler to remove the dead code
instead of messing with the #ifdefs.
This patch fixes such errors when CONFIG_PM_SLEEP=n:
tegra-i2c 7000c400.i2c: timeout waiting for fifo flush
tegra-i2c 7000c400.i2c: Failed to initialize i2c controller
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The usage of BUG() macro is generally discouraged in kernel, unless
it's a problem that results in a physical damage or loss of data.
This patch removes unnecessary BUG() macros and replaces the rest
with warning.
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Post suspend I2C registers have power on reset values. Before any
transfer initialize I2C registers to prevent I2C transfer timeout
and implement suspend and resume callbacks needed. Fix below errors
post suspend:
1) Tegra I2C transfer timeout during jetson tx2 resume:
[ 27.520613] pca953x 1-0074: calling pca953x_resume+0x0/0x1b0 @ 2939, parent: i2c-1
[ 27.633623] tegra-i2c 3160000.i2c: i2c transfer timed out
[ 27.639162] pca953x 1-0074: Unable to sync registers 0x3-0x5. -110
[ 27.645336] pca953x 1-0074: Failed to sync GPIO dir registers: -110
[ 27.651596] PM: dpm_run_callback(): pca953x_resume+0x0/0x1b0 returns -110
[ 27.658375] pca953x 1-0074: pca953x_resume+0x0/0x1b0 returned -110 after 127152 usecs
[ 27.666194] PM: Device 1-0074 failed to resume: error -110
2) Tegra I2C transfer timeout error on jetson Xavier post resume.
Remove i2c bus lock-unlock calls in resume callback as i2c_mark_adapter_*
(suspended-resumed) help ensure i2c core calls from client are not
executed before i2c-tegra resume.
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the driver defers probe because of a missing clock, avoid outputting
an error message. The clock will show up eventually.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fix checkpatch.pl WARNING for delay of approximately 1msec
in flush i2c FIFO polling loop by using usleep_range(1000, 2000):
WARNING: msleep < 20ms can sleep for up to 20ms; see ...
Documentation/timers/timers-howto.txt
+ msleep(1);
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fix checkpatch.pl alignment and blank line check(s) in i2c-tegra.c
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Remove variable initializations in functions that
are followed by assignments before use
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Commit 86c92b9965 ("i2c: tegra: Add DMA support") added DMA support
to the Tegra I2C driver for Tegra devices that support the APB DMA
controller. One side-effect of this change is that even for Tegra
devices that do not have an APB DMA controller and hence, cannot
support DMA tranfers for I2C transactions, the following error messages
are still displayed ...
ERR KERN tegra-i2c 31c0000.i2c: cannot use DMA: -19
ERR KERN tegra-i2c 31c0000.i2c: falling back to PIO
There is no point displaying the above messages for devices that do not
have an APB DMA controller and so fix this by returning from the
tegra_i2c_init_dma() function if 'has_apb_dma' is not true.
Furthermore, if CONFIG_TEGRA20_APB_DMA is not set, then rather than
printing an error message, print an debug message as for whatever reason
this could be intentional.
Fixes: 86c92b9965 ("i2c: tegra: Add DMA support")
Signed-off-by: Jonathan Hunter <jonathanh@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Multi-master support is defeatured on Tegra210 and Tegra186 due to
known bugs.
This patch removes multi-master support for Tegra210 and Tegra186
I2C HW feature.
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra186 does not have master FIFO control register and instead
uses FIFO control register like prior Tegra chipset.
This patch fixes this and prevents crashing during boot when
accessing FIFO control registers.
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The phrasing in two dev_err messages is using fallbacking which
os less understandable than "falling back", so fix this up.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds I2C interface timing registers support for
proper bus rate configuration along with meeting the I2C spec
setup and hold times based on the tuning performed on Tegra210,
Tegra186 and Tegra194 platforms.
I2C_INTERFACE_TIMING_0 register contains TLOW and THIGH field
and Tegra I2C controller design uses them as a part of internal
clock divisor.
I2C_INTERFACE_TIMING_1 register contains the setup and hold times
for start and stop conditions.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra194 allows max of 64K bytes and Tegra186 and prior allows
max of 4K bytes of transfer per packet.
one sec timeout is not enough for transfers more than 10K bytes
at STD bus rate.
This patch updates I2C transfer timeout based on the transfer size
and I2C bus rate to allow enough time during max transfer size at
lower bus speed.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds DMA support for Tegra I2C.
Tegra I2C TX and RX FIFO depth is 8 words. PIO mode is used for
transfer size of the max FIFO depth and DMA mode is used for
transfer size higher than max FIFO depth to save CPU overhead.
PIO mode needs full intervention of CPU to fill or empty FIFO's
and also need to service multiple data requests interrupt for the
same transaction. This adds delay between data bytes of the same
transfer when CPU is fully loaded and some slave devices has
internal timeout for no bus activity and stops transaction to
avoid bus hang. DMA mode is helpful in such cases.
DMA mode is also helpful for Large transfers during downloading or
uploading FW over I2C to some external devices.
Tegra210 and prior Tegra chips use APBDMA driver which is replaced
with GPCDMA on Tegra186 and Tegra194.
This patch uses has_apb_dma flag in hw_feature to differentiate
DMA driver change between Tegra chipset.
APBDMA driver is registered from module-init level and this patch
also has a change to register I2C driver at module-init level
rather than subsys-init to avoid deferring I2C probe till APBDMA
driver is registered.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra194 supports maximum 64K bytes per packet including 12 bytes of
packet header irrespective of PIO or DMA mode transfer.
This patch updates Tegra194 max write length to account for packet
header size for transfers.
Cc: stable@vger.kernel.org # 4.20+
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra186 and prior supports maximum 4K bytes per packet transfer
including 12 bytes of packet header.
This patch fixes max write length limit to account packet header
size for transfers.
Cc: stable@vger.kernel.org # 4.4+
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Bus clear feature of Tegra I2C controller helps to recover from
bus hang when I2C master loses the bus arbitration due to the
slave device holding SDA LOW continuously for some unknown reasons.
Per I2C specification, the device that held the bus LOW should
release it within 9 clock pulses.
During bus clear operation, Tegra I2C controller sends 9 clock
pulses and terminates the transaction with STOP condition.
Upon successful bus clear operation, bus goes to idle state and
driver retries the transaction.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch sorts all the include headers alphabetically for the
I2C Tegra driver.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra194 supports maximum 64K Bytes transfer per packet.
Tegra186 and prior supports maximum 4K Bytes transfer per packet.
This patch fixes this payload difference between Tegra194 and prior
Tegra chipsets using separate i2c_adapter_quirks.
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Not all fields were properly documented. Add kerneldoc for the missing
fields to prevent the build from flagging them.
Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Some of the kerneldoc uses a strange spelling for abbreviations. Turn
them into all-uppercase and clean up some whitespace issues while at it.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
As you are already in ISR, it is unnecessary to call spin_lock_irqsave.
Signed-off-by: jun qian <hangdianqj@163.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
And don't reimplement in the driver.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
On Tegra30 Cardhu the PCA9546 I2C mux is not ACK'ing I2C commands on
resume from suspend (which is caused by the reset signal for the I2C
mux not being configured correctl). However, this NACK is causing the
Tegra30 to hang on resuming from suspend which is not expected as we
detect NACKs and handle them. The hang observed appears to occur when
resetting the I2C controller to recover from the NACK.
Commit 77821b4678 ("i2c: tegra: proper handling of error cases") added
additional error handling for some error cases including NACK, however,
it appears that this change conflicts with an early fix by commit
f70893d083 ("i2c: tegra: Add delay before resetting the controller
after NACK"). After commit 77821b4678 was made we now disable 'packet
mode' before the delay from commit f70893d083 happens. Testing shows
that moving the delay to before disabling 'packet mode' fixes the hang
observed on Tegra30. The delay was added to give the I2C controller
chance to send a stop condition and so it makes sense to move this to
before we disable packet mode. Please note that packet mode is always
enabled for Tegra.
Fixes: 77821b4678 ("i2c: tegra: proper handling of error cases")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org
In order to support advanced features, the I2C FIFO interface was
changed in the version of the Tegra I2C controller found in Tegra194.
The changes are backwards incompatible, so the driver needs to be
programmed in a slightly different way on new chips.
Add support for MST FIFO programming and add an OF match entry for
Tegra194. At the same time, mark all prior generations of this
controller as not having the MST FIFO interface.
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Nothing prevents I2C clients to access I2C while Tegra's driver is being
suspended, this results in -EBUSY error returned to the clients and that
may have unfortunate consequences. In particular this causes problems
for the TPS6586x MFD driver which emits hundreds of "failed to read
interrupt status" error messages on resume from suspend. This happens if
TPS6586X is used to wake system from suspend by the expired RTC alarm
timer because TPS6586X is an I2C device driver and its IRQ handler reads
the status register while Tegra's I2C driver is suspended, i.e. just after
kernel enabled IRQ's during of resume-from-suspend process.
Note that the removed tegra_i2c_resume() invoked tegra_i2c_init() which
performs HW reset. That seems was also not entirely correct because moving
tegra_i2c_resume to an earlier stage of resume-from-suspend process causes
I2C transfer to fail in the case of TPS6586X. It is fine to remove the
HW-reinitialization for now because it should be only needed in a case of
using lowest power-mode during suspend, which upstream kernel doesn't
support.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Make these const as they are only stored as a reference in the quirks
field of an i2c_adapter structure, which is const. Done using
Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Commit a53e35db70 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.
No functional changes.
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-i2c@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fix the following warnings reported by coccinelle for the Tegra I2C
driver.
drivers/i2c/busses/i2c-tegra.c:513:2-23: WARNING: Assignment of bool to 0/1
drivers/i2c/busses/i2c-tegra.c:539:3-24: WARNING: Assignment of bool to 0/1
Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
To summarize the issue observed in error cases:
SW Flow: For i2c message transfer, packet header and data payload is
posted and then required error/packet completion interrupts are enabled
later.
HW flow: HW process the packet just after packet header is posted, if
ARB lost/NACK error occurs (SW will not handle immediately when error
happens as error interrupts are not enabled at this point). HW assumes
error is acknowledged and clears current data in FIFO, But SW here posts
the remaining data payload which still stays in FIFO as stale data
(data without packet header).
Now once the interrupts are enabled, SW handles ARB lost/NACK error by
clearing the ARB lost/NACK interrupt. Now HW assumes that SW attended
the error and will parse/process stale data (data without packet header)
present in FIFO which causes invalid NACK errors.
Fix: Enable the error interrupts before posting the packet into FIFO
which make sure HW to not clear the fifo. Also disable the packet mode
before acknowledging errors (ARB lost/NACK error) to not process any
stale data. As error interrupts are enabled before posting the packet
header use spinlock to avoid preempting.
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use readl_poll_timeout_atomic() function as *wait_for_config_load()
function can be called from interrupt context.
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Define separate function for configuration load register handling
to make it use by different functions later.
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
During i2c controller initialization, when fifo flush fails return error
instead of returning the error during exit.
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
After CONFIG_LOAD register is programmed instead of explicitly waiting
for timeout, use readl_poll_timeout() to check for register value to get
updated or wait till timeout.
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
On Tegra124/132 the pins for I2C6 are shared with the Display Port AUX
(DPAUX) channel and on Tegra210 the pins for I2C4 and I2C6 are shared
with DPAUX1 and DPAUX0, respectively. The multiplexing of the pins is
handled by a register in the DPAUX and so the Tegra DPAUX driver has
been updated to register a pinctrl device for managing these pins.
The pins for these particular I2C devices are bound to the I2C device
prior to probing. However, these I2C devices are in a different power
partition to the DPAUX devices that own the pins. Hence, it is desirable
to place the pins in the 'idle' state and allow the DPAUX power
partition to switch off, when these I2C devices is not in use.
Therefore, add calls to place the I2C pins in the 'default' and 'idle'
states when the I2C device is runtime resumed and suspended,
respectively.
Please note that the pinctrl functions that set the state of the pins
check to see if the devices has pins associated and will return zero
if they do not. Therefore, it is safe to call these pinctrl functions
even for I2C devices that do not have any pins associated.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Update the Tegra I2C driver to use runtime PM and move the code in the
tegra_i2c_clock_enable/disable() functions to the PM runtime resume and
suspend callbacks, respectively.
Note that given that CONFIG_PM is not mandatory for Tegra, if CONFIG_PM
is not enabled and so runtime PM is not enabled, ensure that the I2C
clocks are turned on during probe and kept on by calling the resume
callback directly.
In the function tegra_i2c_init(), the variable 'err' does not need to be
initialised to zero in tegra_i2c_init() because it is initialised when
pm_runtime_get_sync() is called. Furthermore, to ensure we only return 0
from tegra_i2c_init(), it is necessary to re-initialise 'err' to 0 after
a successful call to pm_runtime_get_sync() because it can return a
positive value on success. However, alternatively re-initialise 'err' by
using the return value of the function tegra_i2c_flush_fifos() because
it can only be 0 or -ETIMEDOUT.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The I2C adapter is unlocked regardless of whether the tegra_i2c_init()
called during the resume is successful or not. However, if the
tegra_i2c_init() is not successful, then ->is_suspended is not set to
false. Simplify the resume code by only setting ->is_suspended to false
if tegra_i2c_init() is successful and return the error code from
tegra_i2c_init().
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
All Tegra I2C devices have the name "Tegra I2C adapter" which is not
very useful when viewing the I2C adapter names via the sysfs. Therefore,
use the device name, which is unique for each I2C device, instead.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra has only supported device-tree for platform/board configuration
for quite some time now and so simplify the Tegra I2C driver by dropping
code for non device-tree platforms/boards.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add missing new line characters for the various error messages.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Checkpatch warns about missing blank lines after declarations in the
Tegra I2C driver and so fix these.
Note that the initialisation of 'val' to zero in tegra_dvc_init() is
unnecessary and so remove this.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Checkpatch warns about spacing around the '<<' operator in the Tegra I2C
driver and so fix these by converting the bit definitions that are using
this operator to use the BIT macro.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Checkpatch warns about some lines over 80 characters in the Tegra I2C
driver and so fix these.
While we are at it, prefix the second instance of "STOP condition" in
the comment with a "the".
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The core will do this for us now.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Commit 497fbe2498 ("i2c: tegra: enable multi master mode for tegra210")
enables the Tegra I2C 'div_clk' for adapters using the multi-master mode
during the device probe. Although the probe error path was updated to
disable the clock on probe failure, there is one place after calling
tegra_i2c_init() where the clock will not be disabled on failure. Correct
the error path so that the 'div_clk' is disabled if calling
tegra_i2c_init() fails.
Fixes: 497fbe2498 ("i2c: tegra: enable multi master mode for tegra210")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Disable clock before returning error in tegra_i2c_init() as its leaves
i2c clock ON in case of error and never turns off again as it will have
unbalanced clock enable/disable
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Enable multi-master mode in I2C_CNFG reg based on hw features.
Using single/multi-master mode bit introduced for Tegra210,
whereas multi-master mode is enabled by default in HW for T124 and
earlier Tegra SOC. Enabling this bit doesn't explicitly start
treating the bus has having multiple masters, but will start
checking for arbitration lost and reporting when it occurs.
The Tegra210 I2C controller supports single/multi master mode.
Add chipdata for Tegra210 and its compatibility string so that
Tegra210 will select data that enables multi master mode correctly.
Do below prerequisites for multi-master bus if "multi-master"
dt property entry is added.
1. Enable 1st level clock always set.
2. Disable 2nd level clock gating (slcg which
is supported from T124 SOC and later chips)
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This change will also make Coverity happy by avoiding a theoretical NULL
pointer dereference; yet another reason is to use the above helper function
to tighten the code and make it more readable.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Laxman Dewangan <ldewangan@nvidia.com>
This code is repeated in probe:
i2c_dev->adapter.algo = &tegra_i2c_algo;
Cc: Donglin Peng <pengdonglin137@163.com>
Signed-off-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra I2C controller required to configure the clock divisor
register inside controller to different value based on the clock
speed. The recommended clock divisor for the I2C controller for
standard/fast mode is 0x19 and for fast-mode plus is 0x10.
Add support to configure clock divisor register of I2C controller
based on bus clock rate.
This clock divisor is supported form T114 onwards.
Signed-off-by: Chaitanya Bandi <bandik@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Once the new configuration is set on the conifg register of
I2C controller, it is require to update the CONFIG_LOAD register
to transfer the new SW configuration to actual HW internal
registers that would be used in the actual logic.
It is like, SW is programming only shadow registers through
regular configuration and when these load_config bit fields
are set to 1, it causes the regular/shadows registers
configuration transferred to the HW internal active registers.
So SW has to set these bit fields at the end of all regular
registers configuration. And these config_load bits are HW
auto-clear bits. HW clears these bit fields once the register
configuration is moved to HW internal active registers. So SW
has to wait until these bits are auto-cleared before going
for any further programming
This mechanism is supported on T124 and after this SoCs.
Signed-off-by: Chaitanya Bandi <bandik@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
payload_size is a 12 bit field in the HW register, so add a limit for
this size. That way we gracefully reject the message beforehand instead
of generating an OOPS while transferring. Verified using some older
Tegra2 documentation and a more recent Jetson TK1 board.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
This HW cannot send 0-byte-length messages and the driver discards them.
So, we should not advertise SMBUS_QUICK.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
return type of wait_for_completion_timeout is unsigned long not int. As ret
was only used for wait_for_completion_timeout here it is renamed to time_left
the type changed to unsigned long and references fixed up.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Support CPU BE mode by adding endianness conversion for memcpy interactions.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
