iio: adc: aspeed: Remove the trim valid dts property.

The dts property "aspeed,trim-data-valid" is currently used to determine
whether to read trimming data from the OTP register. If this is set on
a device without valid trimming data in the OTP the ADC will not function
correctly. This patch drops the use of this property and instead uses the
default (unprogrammed) OTP value of 0 to detect when a fallback value of
0x8 should be used rather then the value read from the OTP.

Fixes: d0a4c17b4073 ("iio: adc: aspeed: Get and set trimming data.")
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20221114025057.10843-1-billy_tsai@aspeedtech.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Fix refcount leak in aspeed_adc_set_trim_data

of_find_node_by_name() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.

Fixes: d0a4c17b4073 ("iio: adc: aspeed: Get and set trimming data.")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220516075206.34580-1-linmq006@gmail.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Add divider flag to fix incorrect voltage reading.

The formula for the ADC sampling period in ast2400/ast2500 is:
ADC clock period = PCLK * 2 * (ADC0C[31:17] + 1) * (ADC0C[9:0])
When ADC0C[9:0] is set to 0 the sampling voltage will be lower than
expected, because the hardware may not have enough time to
charge/discharge to a stable voltage. This patch use the flag
CLK_DIVIDER_ONE_BASED which will use the raw value read from the
register, with the value of zero considered invalid to conform to the
corrected formula.

Fixes: 573803234e72 ("iio: Aspeed ADC")
Reported-by: Konstantin Klubnichkin <kitsok@yandex-team.ru>
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20220221012705.22008-1-billy_tsai@aspeedtech.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Fix spelling mistake "battey" -> "battery"

There is a spelling mistake in a dev_warn message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20211001120018.17570-1-colin.king@canonical.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Get and set trimming data.

The ADC controller has a trimming register for fine-tune the reference
voltage. The trimming value comes from the OTP register which will be
written during chip production. This patch will read this OTP value and
configure it to the ADC register when the ADC controller probes and using
dts property "aspeed,trim-data-valid" to determine whether to execute this
flow.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-12-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Support battery sensing.

In ast2600, ADC integrate dividing circuit at last input channel for
battery sensing. This patch use the dts property "battery-sensing" to
enable this feature makes the last channel of each adc can tolerance
higher voltage than reference voltage. The offset interface of ch7 will
be separated when enabling the battery sensing mode.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-11-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Add compensation phase.

This patch adds a compensation phase to improve the accuracy of ADC
measurement. This is the built-in function through input half of the
reference voltage to get the ADC offset.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-10-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Add func to set sampling rate.

Add the function to set the sampling rate and keep the sampling period
for a driver used to wait the fresh value.
In addition, since the ADC clock is required when initializing the ADC
device, move clk_prepare_enable ahead of the initialization phase.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-9-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Fix the calculate error of clock.

The ADC clock formula is
ast2400/2500:
ADC clock period = PCLK * 2 * (ADC0C[31:17] + 1) * (ADC0C[9:0] + 1)
ast2600:
ADC clock period = PCLK * 2 * (ADC0C[15:0] + 1)
They all have one fixed divided 2 and the legacy driver didn't handle it.
This patch register the fixed factory clock device as the parent of ADC
clock scaler to fix this issue.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-8-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Support ast2600 adc.

Make driver to support ast2600 adc device.
- Use shared reset controller
- Complete the vref configure function
- Add the model data for ast2600 adc

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-7-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Use devm_add_action_or_reset.

This patch use devm_add_action_or_reset to handle the error in probe
phase.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-6-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Use model_data to set clk scaler.

This patch uses need_prescaler and scaler_bit_width to set the ADC clock
scaler.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-5-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Add vref config function

Add the function to check the vref_fixed_mv and set the value to driver
data.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-4-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Restructure the model data

This patch refactors the model data structure to distinguish the
function form different versions of aspeed ADC.
- Rename the vref_voltage to vref_fixed_mv and add vref_mv driver data
When driver probe will check vref_fixed_mv value and store it to vref_mv
which isn't const value.
- Add num_channels
Make num_channles of iio device can be changed by different model_data
- Add need_prescaler flag and scaler_bit_width
The need_prescaler flag is used to tell the driver the clock divider needs
another Prescaler and the scaler_bit_width to set the clock divider
bitfield width.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-3-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Keep model data to driver data.

Keep the model data pointer to driver data for reducing the usage of
of_device_get_match_data().

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210922081520.30580-2-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: completes the bitfield declare.

This patch completes the declare of ADC register bitfields and uses the
same prefix ASPEED_ADC_* for these bitfields. In addition, tidy up space
alignment of the codes.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210831071458.2334-4-billy_tsai@aspeedtech.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: set driver data when adc probe.

Fix the issue when adc remove will get the null driver data.

Fixed: commit 573803234e72 ("iio: Aspeed ADC")
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20210831071458.2334-2-billy_tsai@aspeedtech.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: remove explicit IIO device parent assignment

This patch applies the semantic patch:
@@
expression I, P, SP;
@@
I = devm_iio_device_alloc(P, SP);
...
- I->dev.parent = P;

It updates 302 files and does 307 deletions.
This semantic patch also removes some comments like
'/* Establish that the iio_dev is a child of the i2c device */'

But this is is only done in case where the block is left empty.

The patch does not seem to cover all cases. It looks like in some cases a
different variable is used in some cases to assign the parent, but it
points to the same reference.
In other cases, the block covered by ... may be just too big to be covered
by the semantic patch.

However, this looks pretty good as well, as it does cover a big bulk of the
drivers that should remove the parent assignment.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: use devm_platform_ioremap_resource

Reduces boilerplate.

Identified by: Coccinelle / coccicheck

CHECK drivers/iio/adc/aspeed_adc.c
drivers/iio/adc/aspeed_adc.c:189:1-11: WARNING: Use devm_platform_ioremap_resource for data -> base

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Rick Altherr <raltherr@google.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 422

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 101 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190113.822954939@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: adc: aspeed: Fix error handling path

The labels and branching order of the error path of 'aspeed_adc_probe()'
are broken.
Re-order the labels and goto statements.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: aspeed: Deassert reset in probe

The ASPEED SoC must deassert a reset in order to use the ADC peripheral.

The device tree bindings are updated to document the resets phandle, and
the example is updated to match what is expected for both the reset and
clock phandle. Note that the bindings should have always had the reset
controller, as the hardware is unusable without it.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio:adc: drop assign iio_info.driver_module and iio_trigger_ops.owner

The equivalent of both of these are now done via macro magic when
the relevant register calls are made. The actual structure
elements will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>

iio: aspeed-adc: wait for initial sequence.

This patch enables adc engine at initialization time and waits
for the initial sequence completion before enabling adc channels.

Without this code adc channels are not functional and shows
zeros for all connected channels.

Tested on mellanox msn platform.

v1 -> v2:
Pointed by Rick Altherr:
- Wait init sequence code enabled by bool
from OF match table.

Signed-off-by: Mykola Kostenok <c_mykolak@mellanox.com>
Reviewed-by: Rick Altherr <raltherr@google.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: Aspeed ADC - Handle return value of clk_prepare_enable

clk_prepare_enable() can fail here and we must check its return value.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Reviewed-by: Rick Altherr <raltherr@google.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Aspeed ADC

Aspeed BMC SoCs include a 16 channel, 10-bit ADC. Low and high threshold
interrupts are supported by the hardware but are not currently implemented.

Signed-off-by: Rick Altherr <raltherr@google.com>
Tested-by: Xo Wang <xow@google.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>