Commit Graph

10 Commits

Author SHA1 Message Date
Marijn Suijten
d27bb69dc8
regulator: qcom-labibb: OCP interrupts are not a failure while disabled
Receiving the Over-Current Protection interrupt while the regulator is
disabled does not count as unhandled/failure (IRQ_NONE, or 0 as it were)
but a "fake event", usually due to inrush as the is regulator about to
be enabled.

Fixes: 390af53e04 ("regulator: qcom-labibb: Implement short-circuit and over-current IRQs")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Link: https://lore.kernel.org/r/20211224113450.107958-1-marijn.suijten@somainline.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-12-24 14:07:02 +00:00
Matti Vaittinen
89a6a5e56c
regulator: add property parsing and callbacks to set protection limits
Add DT property parsing code and setting callback for regulator over/under
voltage, over-current and temperature error limits.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/e7b8007ba9eae7076178bf3363fb942ccb1cc9a5.1622628334.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-06-21 13:08:41 +01:00
Matti Vaittinen
337710b312
regulator: qcom-labibb: Use disable_irq_nosync from isr
Calling the disable_irq() from irq handler might be a bad idea as
disable_irq() should wait for handlers to run. I don't see why
this wouldn't deadlock in wait_event waiting for the threaded
handler to complete.

Use disable_irq_nosync() instead.

Fixes: 390af53e04 ("regulator: qcom-labibb: Implement short-circuit and over-current IRQs")

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reviewed-by: AngeloGioacchino Del Regno  <angelogioacchino.delregno@somainline.org>
Link: https://lore.kernel.org/r/f2c4c88d90bf7473e1b84b8a99b7b33d7a081764.1612249657.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-02 16:14:16 +00:00
AngeloGioacchino Del Regno
390af53e04
regulator: qcom-labibb: Implement short-circuit and over-current IRQs
Short-Circuit Protection (SCP) and Over-Current Protection (OCP) are
very important for regulators like LAB and IBB, which are designed to
provide from very small to relatively big amounts of current to the
device (normally, a display).

Now that this regulator supports both voltage setting and current
limiting in this driver, to me it looked like being somehow essential
to provide support for SCP and OCP, for two reasons:
1. SCP is a drastic measure to prevent damaging "more" hardware in
   the worst situations, if any was damaged, preventing potentially
   drastic issues;
2. OCP is a great way to protect the hardware that we're powering
   through these regulators as if anything bad happens, the HW will
   draw more current than expected: in this case, the OCP interrupt
   will fire and the regulators will be immediately shut down,
   preventing hardware damage in many cases.

Both interrupts were successfully tested in a "sort-of" controlled
manner, with the following methodology:

Short-Circuit Protection (SCP):
1. Set LAB/IBB to 4.6/-1.4V, current limit 200mA/50mA;
2. Connect a 10 KOhm resistor to LAB/IBB by poking the right traces
   on a FxTec Pro1 smartphone for a very brief time (in short words,
   "just a rapid touch with flying wires");
3. The Short-Circuit protection trips: IRQ raises, regulators get
   cut. Recovery OK, test repeated without rebooting, OK.

Over-Current Protection (OCP):
1. Set LAB/IBB to the expected voltage to power up the display of
   a Sony Xperia XZ Premium smartphone (Sharp LS055D1SX04), set
   current limit to LAB 200mA, IBB 50mA (the values that this
   display unit needs are 200/800mA);
2. Boot the kernel: OCP fires. Recovery never happens because
   the selected current limit is too low, but that's expected.
   Test OK.

3. Set LAB/IBB to the expected current limits for XZ Premium
   (LAB 200mA, IBB 800mA), but lower than expected voltage,
   specifically LAB 5.4V, IBB -5.6V (instead of 5.6, -5.8V);
4. Boot the kernel: OCP fires. Recovery never happens because
   the selected voltage (still in the working range limits)
   is producing a current draw of more than 200mA on LAB.
   Test OK.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Link: https://lore.kernel.org/r/20210119174421.226541-6-angelogioacchino.delregno@somainline.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-20 18:48:17 +00:00
AngeloGioacchino Del Regno
3bc7cb99fb
regulator: qcom-labibb: Implement pull-down, softstart, active discharge
Soft start is required to avoid inrush current during LAB ramp-up and
IBB ramp-down, protecting connected hardware to which we supply voltage.

Since soft start is configurable on both LAB and IBB regulators, it
was necessary to add two DT properties, respectively "qcom,soft-start-us"
to control LAB ramp-up and "qcom,discharge-resistor-kohms" to control
the discharge resistor for IBB ramp-down, which obviously brought the
need of implementing a of_parse callback for both regulators.

Finally, also implement pull-down mode in order to avoid unpredictable
behavior when the regulators are disabled (random voltage spikes etc).

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210119174421.226541-4-angelogioacchino.delregno@somainline.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-20 18:48:16 +00:00
AngeloGioacchino Del Regno
8056704ba9
regulator: qcom-labibb: Implement current limiting
LAB and IBB regulators can be current-limited by setting the
appropriate registers, but this operation is granted only after
sending an unlock code for secure access.

Besides the secure access, it would be possible to use the
regmap helper for get_current_limit, as there is no security
blocking reads, but I chose not to as to avoid having a very
big array containing current limits, especially for IBB.

That said, these regulators support current limiting for:
- LAB (pos): 200-1600mA, with 200mA per step (8 steps),
- IBB (neg):   0-1550mA, with  50mA per step (32 steps).

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Link: https://lore.kernel.org/r/20210119174421.226541-3-angelogioacchino.delregno@somainline.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-20 18:48:15 +00:00
AngeloGioacchino Del Regno
9a12eb704e
regulator: qcom-labibb: Switch voltage ops from linear_range to linear
The LAB and IBB regulator have just one range and it is useless
to use linear_range ops, as these are used to express multiple
linear ranges.

Switch list_voltage and map_voltage callbacks to *_linear instead.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Link: https://lore.kernel.org/r/20210119174421.226541-2-angelogioacchino.delregno@somainline.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-20 18:48:14 +00:00
AngeloGioacchino Del Regno
dd582369c6
regulator: qcom-labibb: Implement voltage selector ops
Implement {get,set}_voltage_sel, list_voltage, map_voltage with
the useful regulator regmap helpers in order to be able to manage
the voltage of LAB (positive) and IBB (negative) regulators.

In particular, the supported ranges are the following:
- LAB (pos):  4600mV to  6100mV with 100mV stepping,
- IBB (neg): -7700mV to -1400mV with 100mV stepping.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210113194214.522238-2-angelogioacchino.delregno@somainline.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-15 14:27:50 +00:00
Rikard Falkeborn
e6f5ff17ca
regulator: qcom: labibb: Constify static structs
The only usage of qcom_labibb_ops is to assign it to the ops field in
the regulator_desc struct, which is a const pointer. The only usage of
pmi8998_lab_desc and pmi8998_ibb_desc is to assign their address to the
desc field in the labibb_regulator_data struct which can be made const,
since it is only copied into the desc field in the
labbibb_regulator_data struct. This struct is modified, but that's a
copy of the static one. Make them const to allow the compiler to put
them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20200930162602.18583-1-rikard.falkeborn@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-10-01 21:43:16 +01:00
Nisha Kumari
498ab2fdf8
regulator: qcom: Add labibb driver
Qualcomm platforms have LAB(LCD AMOLED Boost)/IBB(Inverting Buck Boost)
regulators, labibb for short, which are used as power supply for
LCD Mode displays.

This patch adds labibb regulator driver for pmi8998 PMIC, found on
SDM845 platforms.

  [sumits: reworked the driver design as per upstream review]

Signed-off-by: Nisha Kumari <nishakumari@codeaurora.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://lore.kernel.org/r/20200622124110.20971-5-sumit.semwal@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-07-15 15:47:16 +01:00