28 Commits

Author SHA1 Message Date
Yannick Brosseau
62284d45e2 iio: adc: stm32: Fix ADCs iteration in irq handler
commit d2214cca4d3eadc74eac9e30301ec7cad5355f00 upstream.

The irq handler was only checking the mask for the first ADCs in the case of the
F4 and H7 generation, since it was iterating up to the num_irq value. This patch add
the maximum number of ADC in the common register, which map to the number of entries of
eoc_msk and ovr_msk in stm32_adc_common_regs. This allow the handler to check all ADCs in
that module.

Tested on a STM32F429NIH6.

Fixes: 695e2f5c289b ("iio: adc: stm32-adc: fix a regression when using dma and irq")
Signed-off-by: Yannick Brosseau <yannick.brosseau@gmail.com>
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20220516203939.3498673-2-yannick.brosseau@gmail.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-29 08:59:52 +02:00
Olivier Moysan
3e0af68b99 iio: adc: stm32: fix maximum clock rate for stm32mp15x
commit 990539486e7e311fb5dab1bf4d85d1a8973ae644 upstream.

Change maximum STM32 ADC input clock rate to 36MHz, as specified
in STM32MP15x datasheets.

Fixes: d58c67d1d851 ("iio: adc: stm32-adc: add support for STM32MP1")
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20220609095234.375925-1-olivier.moysan@foss.st.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-29 08:59:52 +02:00
Olivier Moysan
695e2f5c28 iio: adc: stm32-adc: fix a regression when using dma and irq
Since overrun interrupt support has been added, there's a regression when
two ADCs are used at the same time, with:
- an ADC configured to use IRQs. EOCIE bit is set. The handler is normally
  called in this case.
- an ADC configured to use DMA. EOCIE bit isn't set. EOC triggers the DMA
  request. It's then automatically cleared by DMA read. But the handler
  gets called due to status bit is temporarily set (IRQ triggered by the
  other ADC).

This is a regression as similar issue had been fixed earlier by
commit dcb10920179a ("iio: adc: stm32-adc:
fix a race when using several adcs with dma and irq").
Issue is that stm32_adc_eoc_enabled() returns non-zero value (always)
since OVR bit has been added and enabled for both DMA and IRQ case.

Remove OVR mask in IER register, and rely only on CSR status for overrun.
To avoid subsequent calls to interrupt routine on overrun, CSR OVR bit has
to be cleared. CSR OVR bit cannot be cleared directly by software.
To do this ADC must be stopped first, and OVR bit in ADC ISR has
to be cleared.
Also add a check in ADC IRQ handler to report spurious IRQs.

Fixes: cc06e67d8fa5 ("iio: adc: stm32-adc: Add check on overrun interrupt")
Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201021085313.5335-1-olivier.moysan@st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-11-01 17:14:06 +00:00
Fabrice Gasnier
c537d34575 iio: adc: stm32-adc: fix runtime autosuspend delay when slow polling
When the ADC is runtime suspended and starting a conversion, the stm32-adc
driver calls pm_runtime_get_sync() that gets cascaded to the parent
(e.g. runtime resume of stm32-adc-core driver). This also kicks the
autosuspend delay (e.g. 2s) of the parent.
Once the ADC is active, calling pm_runtime_get_sync() again (upon a new
capture) won't kick the autosuspend delay for the parent (stm32-adc-core
driver) as already active.

Currently, this makes the stm32-adc-core driver go in suspend state
every 2s when doing slow polling. As an example, doing a capture, e.g.
cat in_voltageY_raw at a 0.2s rate, the auto suspend delay for the parent
isn't refreshed. Once it expires, the parent immediately falls into
runtime suspended state, in between two captures, as soon as the child
driver falls into runtime suspend state:
- e.g. after 2s, + child calls pm_runtime_put_autosuspend() + 100ms
  autosuspend delay of the child.
- stm32-adc-core switches off regulators, clocks and so on.
- They get switched on back again 100ms later in this example (at 2.2s).

So, use runtime_idle() callback in stm32-adc-core driver to call
pm_runtime_mark_last_busy() for the parent driver (stm32-adc-core),
to avoid this.

Fixes: 9bdbb1139ca1 ("iio: adc: stm32-adc: add power management support")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/1593615328-5180-1-git-send-email-fabrice.gasnier@st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-09-29 17:50:51 +01:00
Krzysztof Kozlowski
a5c69204da iio: adc: stm32: Fix missing return in booster error path
Conversion of error paths to dev_err_probe() dropped one return
statement.  The driver will continue to probe if getting booster
regulator fails.

Fixes: ce30eeb613cb ("iio: adc: stm32: Simplify with dev_err_probe()")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/1599727927-7776-1-git-send-email-krzk@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-09-13 10:43:55 +01:00
Krzysztof Kozlowski
ce30eeb613 iio: adc: stm32: Simplify with dev_err_probe()
Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and also it prints the error value.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200829064726.26268-8-krzk@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-09-03 19:40:50 +01:00
Fabrice Gasnier
10134ec3f8 iio: adc: stm32-adc: fix a wrong error message when probing interrupts
A wrong error message is printed out currently, like on STM32MP15:
- stm32-adc-core 48003000.adc: IRQ index 2 not found.

This is seen since commit 7723f4c5ecdb ("driver core: platform: Add an
error message to platform_get_irq*()").
The STM32 ADC core driver wrongly requests up to 3 interrupt lines. It
should request only the necessary IRQs, based on the compatible:
- stm32f4/h7 ADCs share a common interrupt
- stm32mp1, has one interrupt line per ADC.
So add the number of required interrupts to the compatible data.

Fixes: d58c67d1d851 ("iio: adc: stm32-adc: add support for STM32MP1")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-05-22 17:29:25 +01:00
Etienne Carriere
622b4339f9 iio: adc: stm32-adc: don't print an error on probe deferral
Do not print an error trace when deferring probe for some resource.

Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-01-18 14:22:00 +00:00
Fabrice Gasnier
cc06e67d8f iio: adc: stm32-adc: Add check on overrun interrupt
Enable overrun interrupt on STM32 ADC. In case data register hasn't been
read (by CPU or DMA), overrun condition is detected when there's new
conversion data available. Stop grabbing data and log an error message.
Use a threaded irq to avoid printing the error message from hard irq
context.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-12-15 11:42:17 +00:00
Fabrice Gasnier
cb7e1b50e4 iio: adc: stm32: allow to tune analog clock
Add new optional dt property to tune analog clock prescaler.
Driver looks for optional "st,max-clk-rate-hz", then computes
best approximation below that rate, using ADC internal prescaler.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-11-09 12:37:18 +00:00
Fabrice Gasnier
1cd92d42db iio: adc: stm32-adc: fix kernel-doc warnings
Fix the following warnings when documentation is built:
drivers/iio/adc/stm32-adc-core.c:62: warning: cannot understand function
 prototype: 'struct stm32_adc_common_regs '
drivers/iio/adc/stm32-adc-core.c:78: warning: cannot understand function
 prototype: 'struct stm32_adc_priv_cfg '
drivers/iio/adc/stm32-adc-core.c:123: warning: Function parameter or
 member 'pdev' not described in 'stm32f4_adc_clk_sel'
drivers/iio/adc/stm32-adc.c:219: warning: cannot understand function
 prototype: 'struct stm32_adc_regs '
drivers/iio/adc/stm32-adc.c:237: warning: cannot understand function
 prototype: 'struct stm32_adc_regspec '
drivers/iio/adc/stm32-adc.c:264: warning: cannot understand function
 prototype: 'struct stm32_adc_cfg '
drivers/iio/adc/stm32-adc.c:323: warning: Function parameter or member
 'difsel' not described in 'N'
drivers/iio/adc/stm32-adc.c:323: warning: Function parameter or member
 'pcsel' not described in 'stm32_adc'
drivers/iio/adc/stm32-adc.c:371: warning: cannot understand function
 prototype: 'const struct stm32_adc_regs stm32f4_sq[STM32_ADC_MAX_SQ + 1]
drivers/iio/adc/stm32-adc.c:417: warning: cannot understand function
 prototype: 'const struct stm32_adc_regs stm32f4_smp_bits[] = '
drivers/iio/adc/stm32-adc.c:508: warning: cannot understand function
 prototype: 'const struct stm32_adc_regs stm32h7_smp_bits[] = '
drivers/iio/adc/stm32-adc.c:1112: warning: Function parameter or member
 'indio_dev' not described in 'stm32_adc_get_trig_extsel'
drivers/iio/adc/stm32-adc.c:1420: warning: Function parameter or member
 'indio_dev' not described in 'stm32_adc_debugfs_reg_access'
drivers/iio/adc/stm32-adc.c:1420: warning: Function parameter or member
 'reg' not described in 'stm32_adc_debugfs_reg_access'
drivers/iio/adc/stm32-adc.c:1420: warning: Function parameter or member
 'writeval' not described in 'stm32_adc_debugfs_reg_access'
drivers/iio/adc/stm32-adc.c:1420: warning: Function parameter or member
 'readval' not described in 'stm32_adc_debugfs_reg_access'

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-10-22 12:55:27 +01:00
Fabrice Gasnier
dcb1092017 iio: adc: stm32-adc: fix a race when using several adcs with dma and irq
End of conversion may be handled by using IRQ or DMA. There may be a
race when two conversions complete at the same time on several ADCs.
EOC can be read as 'set' for several ADCs, with:
- an ADC configured to use IRQs. EOCIE bit is set. The handler is normally
  called in this case.
- an ADC configured to use DMA. EOCIE bit isn't set. EOC triggers the DMA
  request instead. It's then automatically cleared by DMA read. But the
  handler gets called due to status bit is temporarily set (IRQ triggered
  by the other ADC).
So both EOC status bit in CSR and EOCIE control bit must be checked
before invoking the interrupt handler (e.g. call ISR only for
IRQ-enabled ADCs).

Fixes: 2763ea0585c9 ("iio: adc: stm32: add optional dma support")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-10-09 19:11:26 +01:00
Fabrice Gasnier
31922f62bb iio: adc: stm32-adc: move registers definitions
Move STM32 ADC registers definitions to common header.
This is precursor patch to:
- iio: adc: stm32-adc: fix a race when using several adcs with dma and irq

It keeps registers definitions as a whole block, to ease readability and
allow simple access path to EOC bits (readl) in stm32-adc-core driver.

Fixes: 2763ea0585c9 ("iio: adc: stm32: add optional dma support")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-10-09 19:11:26 +01:00
Stephen Boyd
7c279229f9 iio: Remove dev_err() usage after platform_get_irq()
We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: linux-iio@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-08-05 15:59:14 +01:00
Fabrice Gasnier
3a81bde545 iio: adc: stm32-adc: add analog switches supply control
On stm32h7 and stm32mp1, the ADC inputs are multiplexed with analog
switches which have reduced performances when their supply is below 2.7V
(vdda by default):
- 3.3V embedded booster can be used, to get full ADC performances
  (increases power consumption).
- vdd supply can be selected if above 2.7V by setting ANASWVDD syscfg bit,
  on STM32MP1 only.

Make this optional, since this is a trade-off between analog performance
and power consumption.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-07-27 20:11:16 +01:00
Fabrice Gasnier
7685010fca iio: adc: stm32-adc: add missing vdda-supply
Add missing vdda-supply, analog power supply, to STM32 ADC. When vdda is
an independent supply, it needs to be properly turned on or off to supply
the ADC.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Fixes: 1add69880240 ("iio: adc: Add support for STM32 ADC core").
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-06-22 10:37:26 +01:00
Fabrice Gasnier
9bdbb1139c iio: adc: stm32-adc: add power management support
Add support for runtime PM & sleep. Move all regulator and clock management
to dedicated HW start/stop routines. Then rely on (runtime) PM OPS to
call them.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-11-25 13:15:24 +00:00
Fabrice Gasnier
d58c67d1d8 iio: adc: stm32-adc: add support for STM32MP1
Add support for STM32MP1 ADC. It's quite similar to STM32H7 ADC.
Introduce new compatible to handle variants of this hardware such as
vregready flag, trigger list, interrupts, clock rate.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-05-07 18:21:00 +01:00
Benjamin Gaignard
6e93e26193 iio: stm32: Adopt SPDX identifier
Add SPDX identifier in stm32's files in IIO directory

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-08 16:03:41 +01:00
Fabrice Gasnier
f66f18e99a iio: adc: stm32: add check on clock rate
Add check on STM32 ADC clock rate to report an explicit error.
This may avoid division by 0 later in stm32-adc driver.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-10-21 17:52:20 +01:00
Greg Kroah-Hartman
8439a69e72 Merge 4.13-rc7 into staging-next
We want the staging and iio fixes in here to handle the merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 15:26:48 +02:00
Fabrice Gasnier
50dbe1f4b4 iio: adc: stm32: fix common clock rate
ADC clock input is provided to internal prescaler (that decreases its
frequency). It's then used as reference clock for conversions.

- Fix common clock rate used then by stm32-adc sub-devices. Take common
  prescaler into account. Currently, rate is used to set "boost" mode.
  It may unnecessarily be set. This impacts power consumption.
- Fix ADC max clock rate on STM32H7 (fADC from datasheet). Currently,
  prescaler may be set too low. This can result in ADC reference
  clock used for conversion to exceed max allowed clock frequency.

Fixes: 95e339b6e85d ("iio: adc: stm32: add support for STM32H7")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-07-30 17:18:38 +01:00
Colin Ian King
004123f3df iio: adc: stm32: make array stm32h7_adc_ckmodes_spec static
The array stm32h7_adc_ckmodes_spec does not need to be in global scope, so
make it static.

Cleans up sparse warning:
"symbol 'stm32h7_adc_ckmodes_spec' was not declared. Should it be static?"

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-07-02 10:24:52 +01:00
Fabrice Gasnier
95e339b6e8 iio: adc: stm32: add support for STM32H7
Add support for STM32H7 Analog to Digital Converter. It has up
to 20 external channels, resolution ranges from 8 to 16bits.
Either bus or asynchronous adc clock may be used.

Add registers & bitfields definition. Also add new configuration
options to enter/exit powerdown and perform self-calibration.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-06-11 15:07:29 +01:00
Fabrice Gasnier
64ad7f6438 iio: adc: stm32: introduce compatible data cfg
Prepare support for stm32h7 adc variant by introducing compatible
configuration data.
Move STM32F4 specific stuff to compatible data structure:
- registers & bit fields
- input channels data
- start/stop procedures
- trigger definitions

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-06-11 15:07:25 +01:00
Fabrice Gasnier
9fd243c4fb iio: adc: stm32: make core adc clock optional by default
Analog clock input is mandatory on stm32f4. But newer version of
ADC hardware block allow to select either bus clock or asynchronous
clock, for analog circuitry.

So, make it optional by default, but enforce clk presence on stm32f4.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-06-11 15:07:24 +01:00
Fabrice Gasnier
2763ea0585 iio: adc: stm32: add optional dma support
Add DMA optional support to STM32 ADC, as there is a limited number DMA
channels (request lines) that can be assigned to ADC. This way, driver
may fall back using interrupts when all DMA channels are in use for
other IPs.
Use dma cyclic mode with two periods. Allow to tune period length by
using watermark. Coherent memory is used for dma (max buffer size is
fixed to PAGE_SIZE).

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-29 12:49:17 +00:00
Fabrice Gasnier
1add698802 iio: adc: Add support for STM32 ADC core
Add core driver for STMicroelectronics STM32 ADC (Analog to Digital
Converter). STM32 ADC can be composed of up to 3 ADCs with shared
resources like clock prescaler, common interrupt line and analog
reference voltage.
This core driver basically manages shared resources.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-11-19 12:17:45 +00:00