If a platform device's remove callback returns non-zero, the device core
emits a warning and still removes the device and calls the devm cleanup
callbacks.
So it's not save to not unregister the gpiochip because on the next request
to a GPIO the driver accesses kfree()'d memory. Also if an IRQ triggers,
the freed memory is accessed.
Instead rely on the GPIO framework to ensure that after gpiochip_remove()
all GPIOs are freed and so the corresponding IRQs are unmapped.
This is a preparation for making platform remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
If the teardown callback failed in the gpio driver, it fails to free the
irq (if there is one). The device is removed anyhow. If later on the irq
triggers, all sorts of unpleasant things might happen (e.g. accessing
the struct adp5588_gpio which is already freed in the meantime or starting
i2c bus transfers for an unregistered device). Even before irq support was
added to this driver, exiting early was wrong; back then it failed to
unregister the gpiochip.
Fortunately these callbacks aren't used any more since at least blackfin
was removed in 2018. So just drop them.
Note that they are not removed from struct adp5588_gpio_platform_data
because the keyboard driver adp5588-keys.c also makes use of them.
(I didn't check if the callbacks might have been called twice, maybe there
is another reason hidden to better not call these functions.)
This patch is a preparation for making i2c remove callbacks return void.
Fixes: 80884094e3 ("gpio: adp5588-gpio: new driver for ADP5588 GPIO expanders")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Without this change arch/riscv/kernel/elf_kexec.c fails to compile once
commit 233c1e6c319c ("kexec_file: drop weak attribute from
arch_kexec_apply_relocations[_add]") is also contained in the tree.
This currently happens in next-20220527.
Prepare the RISC-V similar to the s390 adaption done in 233c1e6c319c.
This is safe to do on top of the riscv change even without the change to
arch_kexec_apply_relocations.
Fixes: 838b3e2848 ("RISC-V: Load purgatory in kexec_file")
Looks-good-to: liaochang (A) <liaochang1@huawei.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
On some platforms (i.e. arc, m68k and sparc) __fls returns an int (while
on most platforms it returns an unsigned long). This triggers a format
warning on these few platforms as the driver uses %ld to print a warning.
So explicitly cast the return value to unsigned long to make the warning
go away (and so fix allmodconfig build on the affected architectures).
Fixes: beed983621 ("ASoC: Intel: avs: Machine board registration")
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220529141250.1979827-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Returning an error value in an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.
As tpm_cr50_i2c_remove() emits an error message already and the
additional error message by the i2c core doesn't add any useful
information, change the return value to zero to suppress this error
message.
Note that if i2c_clientdata is NULL, there is something really fishy.
Assuming no memory corruption happened (then all bets are lost anyhow),
tpm_cr50_i2c_remove() is only called after tpm_cr50_i2c_probe() returned
successfully. So there was a tpm chip registered before and after
tpm_cr50_i2c_remove() its privdata is freed but the associated character
device isn't removed. If after that happened userspace accesses the
character device it's likely that the freed memory is accessed. For that
reason the warning message is made a bit more frightening.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Returning an error value in an i2c remove callback results in a generic
error message being emitted by the i2c core, but otherwise it doesn't make
a difference. The device goes away anyhow and the devm cleanups are
called.
So instead of triggering the generic i2c error message, emit a more helpful
message if a problem occurs and return 0 to suppress the generic message.
This patch is a preparation for making i2c remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220502191012.53259-1-u.kleine-koenig@pengutronix.de
An error code returned by devm_clk_get() might have other meanings than
"This clock doesn't exist". So use devm_clk_get_optional() and handle
all remaining errors as fatal.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
An error code returned by devm_clk_get() might have other meanings than
"This clock doesn't exist". So use devm_clk_get_optional() and handle
all remaining errors as fatal.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver doesn't take struct pwm_state::polarity into account when
configuring the hardware, so refuse requests for inverted polarity.
Fixes: 757642f9a5 ("gpio: mvebu: Add limited PWM support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Some (most?) drivers emit the inactive state when the PWM is disabled.
However there are exceptions, so document that a consumer better doesn't
depend on this behaviour.
Some known exceptions:
- imx27 emits 0 independent of the configured polarity
- mxs just drives the output to the last emitted state.
- iqs620a makes the output tristated on disable, so an external
pull-down would be required.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This just pushed a variant of pwm_apply_legacy() into the driver that was
slightly simplified because the driver doesn't provide a .set_polarity()
callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This pushes a variant of pwm_apply_legacy into the driver that was slightly
simplified because the .set_polarity callback was a noop.
There is no change in behavior.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This just pushed a variant of pwm_apply_legacy() into the driver that was
slightly simplified because the driver doesn't provide a .set_polarity()
callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This just pushed a variant of pwm_apply_legacy() into the driver that was
slightly simplified because the driver doesn't provide a .set_polarity()
callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This just pushed a variant of pwm_apply_legacy() into the driver that was
slightly simplified because the driver doesn't provide a .set_polarity()
callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This just pushed a variant of pwm_apply_legacy() into the driver that was
slightly simplified because the driver doesn't provide a .set_polarity()
callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This just pushed a variant of pwm_apply_legacy() into the driver that was
slightly simplified because the driver doesn't provide a .set_polarity()
callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Dividing by the result of a division looses precision because the result is
rounded twice. E.g. with clk_rate = 48000000 and period = 32760033 the
following numbers result:
rate = pc->clk_rate >> PWM_DUTY_WIDTH = 187500
hz = DIV_ROUND_CLOSEST_ULL(100ULL * NSEC_PER_SEC, period_ns) = 3052
rate = DIV_ROUND_CLOSEST_ULL(100ULL * rate, hz) = 6144
The exact result would be 6142.5061875 and (apart from rounding) this is
found by using a single division. As a side effect is also a tad
cheaper to calculate.
Also using clk_rate >> PWM_DUTY_WIDTH looses precision. Consider for
example clk_rate = 47999999 and period = 106667:
mul_u64_u64_div_u64(pc->clk_rate >> PWM_DUTY_WIDTH, period_ns,
NSEC_PER_SEC) = 19
mul_u64_u64_div_u64(pc->clk_rate, period_ns,
NSEC_PER_SEC << PWM_DUTY_WIDTH) = 20
(The exact result is 20.000062083332033.)
With this optimizations also switch from round-closest to round-down for
the period calculation. Given that the calculations were non-optimal for
quite some time now with variations in both directions which nobody
reported as a problem, this is the opportunity to align the driver's
behavior to the requirements of new drivers. This has several upsides:
- Implementation is easier as there are no round-nearest variants of
mul_u64_u64_div_u64().
- Requests for too small periods are now consistently refused. This was
kind of arbitrary before, where period_ns < min_period_ns was
refused, but in some cases min_period_ns isn't actually implementable
and then values between min_period_ns and the actual minimum were
rounded up to the actual minimum.
Note that the duty_cycle calculation isn't using the usual round-down
approach yet.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Dividing by the result of a division looses precision. Consider for example
clk_rate = 33000000 and period_ns = 500001. Then
clk_rate / (NSEC_PER_SEC / period_ns)
has the exact value 16500.033, but in C this evaluates to 16508. It gets
worse for even bigger values of period_ns, so with period_ns = 500000001,
the exact result is 16500000.033 while in C we get 33000000.
For that reason use
clk_rate * period_ns / NSEC_PER_SEC
instead which doesn't suffer from this problem. To ensure this doesn't
overflow add a safeguard check for clk_rate.
Note that duty > period can never happen, so the respective check can be
dropped.
Incidentally this fixes a division by zero if period_ns > NSEC_PER_SEC.
Another side effect is that values bigger than INT_MAX for period and
duty_cyle are not wrongly discarded any more.
Fixes: 99b82abb0a ("pwm: Add Renesas TPU PWM driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The newly computed register values are intended to exactly match the
previously computed values. The main improvement is that the prescaler
is computed without a loop that involves two divisions in each step.
This uses the fact, that prescalers[i] = 1 << (2 * i).
Assuming a moderately smart compiler, the needed number of divisions for
the case where the requested period is too big, is reduced from 5 to 2.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The driver used "pwm" for struct tpu_pwm_device pointers. This name is
usually only used for struct pwm_device pointers which this driver calls
"_pwm". So rename to the driver data pointers to "tpd" which then allows
to drop the underscore from "_pwm".
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
As pwm->state might not be updated in tpu_pwm_apply() before calling
tpu_pwm_config(), an additional parameter is needed for tpu_pwm_config()
to not change the implemented logic.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The added benefit is that the error code is mentioned in the error message
and its usage is a bit more compact than open coding it. This also
improves behaviour in case devm_clk_get() returns -EPROBE_DEFER.
While touching this code, consistently start error messages with upper
case.
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
The size check for state->period is moved to .apply() to make sure that
the values of state->duty_cycle and state->period are passed to
pwm_samsung_config without change while they are discarded to int.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Returning an error value from an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.
As stk3310_set_state() already emits an error message on failure and the
additional error message by the i2c core doesn't add any useful
information, don't pass the error value up the stack. Instead continue
to clean up and return 0.
This patch is a preparation for making i2c remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Returning an error value in an i2c remove callback results in a generic
error message being emitted by the i2c core, but otherwise it doesn't make
a difference. The device goes away anyhow and the devm cleanups are
called.
So instead of triggering the generic i2c error message, emit a more helpful
message if a problem occurs and return 0 to suppress the generic message.
This patch is a preparation for making i2c remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Returning an error value in an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.
As atmel_sha204a_remove already emits an error message ant the additional
error message by the i2c core doesn't add any useful information, change
the return value to zero to suppress this error message.
Note that after atmel_sha204a_remove() returns *i2c_priv is freed, so there
is trouble ahead because atmel_sha204a_rng_done() might be called after
that freeing. So make the error message a bit more frightening.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Returning an error value in an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.
In this case the remove callback even returns early without stopping the
tcpm worker thread and various timers. A work scheduled on the work
queue, or a firing timer after tcpci_remove() returned probably results
in a use-after-free situation because the regmap and driver data were
freed. So better make sure that tcpci_unregister_port() is called even
if disabling the irq failed.
Also emit a more specific error message instead of the i2c core's
"remove failed (EIO), will be ignored" and return 0 to suppress the
core's warning.
This patch is (also) a preparation for making i2c remove callbacks
return void.
Fixes: 3ba76256fc ("usb: typec: tcpci: mask event interrupts when remove driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: stable <stable@vger.kernel.org>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220502080456.21568-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The only user of max732x_platform_data is arch/arm/mach-pxa/littleton.c
and it only uses .gpio_base. So drop the other members from the data struct
and simplify the driver accordingly.
The motivating side effect of this change is that the .remove() callback
cannot return a nonzero error code any more which prepares making i2c
remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Up to now pca9532_destroy_devices() returns always zero because it's
always called with data != NULL. Remove the never-taken error path and
make it return void which makes it easier to see in the callers that
there is no error to handle.
Also the return value of i2c remove callbacks is ignored anyway.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
If twl4030_exit_irq() returns an error, the effect is that the caller
(twl_remove()) forwards the error to the i2c core without unregistering
its dummy slave devices. This only makes the i2c core emit another
error message and then it still removes the device.
In this situation it doesn't make sense to abort the remove cleanup and not
unregister the slave devices. So do that. Then return value is actually
unused and twl4030_exit_irq() can better be changed to return no value at
all.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220113101430.12869-3-u.kleine-koenig@pengutronix.de
This function returns 0 unconditionally, so there is no benefit in
returning a value at all and make the caller do error checking.
Also the caller (twl_remove()) cannot do anything sensible with an error
code. Passing it up the call stack isn't a good option because the i2c core
ignores error codes (apart from emitting an error message).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220113101430.12869-2-u.kleine-koenig@pengutronix.de
The only effect of returning an error code in an i2c remove callback
(compared to returning zero) is that the i2c core emits a generic
warning. The device is still removed.
So even if disabling the regulators fails it's sensible to return zero
to suppress the additional generic and little helpful error message.
This patch is a preparation for making i2c remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220425193206.61710-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
All teardown functions return 0. Also there is little sense in returning
a negative error code from an i2c remove function as this only results in
emitting an error message but the device is removed nevertheless.
This patch is a preparation for making i2c remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
The only effect of returning an error code in an i2c remove callback is
that the i2c core emits a generic warning and still removes the device.
So even if disabling the regulator fails it's sensible to further cleanup
and then return zero to only emit a single error message.
This patch is a preparation for making i2c remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
This fixes a small issue in clps711x_get_duty() en passant: the
multiplication v * 0xf might have overflown.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The reg member of struct raspberrypi_pwm_prop is a little endian 32 bit
quantity. Explicitly convert the (native endian) value to little endian
on assignment as is already done in raspberrypi_pwm_set_property().
This fixes the following sparse warning:
drivers/pwm/pwm-raspberrypi-poe.c:69:24: warning: incorrect type in initializer (different base types)
drivers/pwm/pwm-raspberrypi-poe.c:69:24: expected restricted __le32 [usertype] reg
drivers/pwm/pwm-raspberrypi-poe.c:69:24: got unsigned int [usertype] reg
Fixes: 79caa362ea ("pwm: Add Raspberry Pi Firmware based PWM bus")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The array atmel_tcb_divisors is not supposed to be used outside of the
driver, so make it static.
This fixes a sparse warning:
drivers/pwm/pwm-atmel-tcb.c:64:10: warning: symbol 'atmel_tcb_divisors' was not declared. Should it be static?
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The hardware only supports periods <= 1.6 ms and if a bigger period is
requested it is clamped to 1.6 ms. In this case duty_cycle might be bigger
than 1.6 ms and then the duty cycle register is written with a value
bigger than LP3943_MAX_DUTY. So clamp duty_cycle accordingly.
Fixes: af66b3c093 ("pwm: Add LP3943 PWM driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Per-channel data is tracked using struct pwm_device::chip_data and
struct atmel_tcb_pwm_chip::pwms[]. Simplify by using the latter
consistently.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
clocks and clock-names are already present in imx6qdl.dtsi since commit
f3e7dae323 ("ARM: dts: imx6qdl: add enet_out clk support"). The change
to imx6qdl.dtsi was explicitly done to avoid this construct in this
file, so benefit from the change and drop these properties.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The only effect of this symbol is to select PWM_SAMSUNG. Drop it and fix
the affected defconfigs to still keep PWM_SAMSUNG=y. Developers using
MACH_NEO1973_GTA02 and/or MACH_RX1950 now have to manually select PWM and
PWM_SAMSUNG (and get the freedom to select is as a module or not at all).
A side effect of this change is that allmodconfig now contains
PWM_SAMSUNG=m (which was =y before).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220328082638.112185-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Returning a non-zero value in an i2c remove callback results in the i2c
core emitting a very generic error message ("remove failed (-ESOMETHING),
will be ignored") and as the message indicates not further error handling
is done.
Instead emit a more specific error message and then return zero in
.remove().
The long-term goal is to make the i2c remove prototype return void, making
all implementations return 0 is preparatory work for this change.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220214150710.312269-1-u.kleine-koenig@pengutronix.de
Set em485->active_timer = NULL isn't always enough to take out the stop
timer. While there is a check that it acts in the right state (i.e.
waiting for RTS-after-send to pass after sending some chars) but the
following might happen:
- CPU1: some chars send, shifter becomes empty, stop tx timer armed
- CPU0: more chars send before RTS-after-send expired
- CPU0: shifter empty irq, port lock taken
- CPU1: tx timer triggers, waits for port lock
- CPU0: em485->active_timer = &em485->stop_tx_timer, hrtimer_start(),
releases lock()
- CPU1: get lock, see em485->active_timer == &em485->stop_tx_timer,
tear down RTS too early
This fix bases on research done by Steffen Trumtrar.
Fixes: b86f86e8e7 ("serial: 8250: fix potential deadlock in rs485-mode")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220215160236.344236-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure in .probe() to set driver data before the function is left to
make it possible in .remove() to undo the actions done.
This fixes a potential memory leak and stops returning an error code in
.remove() that is ignored by the driver core anyhow.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The lock only protects against concurrent users of the PWM API. This is not
expected to be necessary. And if there was such an issue, this is better
handled in the PWM core instead as it affects all drivers in the same way.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply().
The conversion wasn't quite straight forward because .config() and
.enable() were special to effectively swap their usual order. This resulted
in calculating the required values twice in some cases when
pwm_apply_state() was called. This is optimized en passant, and the order
of the callbacks is preserved without special jumping through hoops.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply(). This just pushes down a slightly
optimized variant of how legacy drivers are handled in the core.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The only difference between returning zero or a non-zero value is that
for the non-zero case the i2c will print a generic error message
("remove failed (-ESOMETHING), will be ignored").
In this case however the driver itself already emitted a more helpful
error message, so the additional error message isn't helpful at all.
The long-term goal is to make the i2c remove callback return void, making
all implementations return 0 is preparatory work for this change.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
When ret is not zero there were already one or two error messages emitted
about a problem (because rt9455_register_reset() emits a message in most
cases then). Passing on that error code to the i2c core only results in
another error message. Suppress that by returning zero unconditionally.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply(). This just pushes down a slightly
optimized variant of how legacy drivers are handled in the core.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
In all code locations but the probe function variables of type struct
stmpe_pwm * are called "stmpe_pwm". Align the name used in
stmpe_pwm_probe() accordingly. Still more as the current name "pwm" is
usually reserved for variables of type struct pwm_device *.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Status quo is that variables of type struct sun4i_pwm_chip * are named
"pwm". This name is usually reserved for variabled of type struct
pwm_chip *.
So consistently use the same and non-conflicting name "sun4ichip" which
better reflects the intend
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Status quo is that variables of type struct tegra_pwm_chip * are named
"pwm", "chip" or "pc". The two formers are all not optimal because
usually only struct pwm_device * variables are named "pwm" and "chip" is
usually used for variabled of type struct pwm_chip *.
So consistently use the same and non-conflicting name "pc".
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Status quo is that variables of type struct img_pwm_chip * are named
"pwm_chip", "pwm" or "chip" which are all not optimal because there is a
struct pwm_chip in the core, usually only struct pwm_device * variables are
named "pwm" and "chip" is usually used for variabled of type struct
pwm_chip *.
So consistently use the same and non-conflicting name "imgchip".
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply(). This just pushes down a slightly
optimized variant of how legacy drivers are handled in the core.
As a side effect this improves the behaviour for big duty cycles where
max * duty_ns overflowed before.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The per-channel data is available directly in the driver data struct. So
use it without making use of pwm_[gs]et_chip_data().
The relevant change introduced by this patch to lpc18xx_pwm_disable() at
the assembler level (for an arm lpc18xx_defconfig build) is:
push {r3, r4, r5, lr}
mov r4, r0
mov r0, r1
mov r5, r1
bl 0 <pwm_get_chip_data>
ldr r3, [r0, #0]
changes to
ldr r3, [r1, #8]
push {r4, lr}
add.w r3, r0, r3, lsl #2
ldr r3, [r3, #92] ; 0x5c
So this reduces stack usage, has an improved runtime behavior because of
better pipeline usage, doesn't branch to an external function and the
generated code is a bit smaller occupying less memory.
The codesize of lpc18xx_pwm_probe() is reduced by 32 bytes.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Each devm allocations has an overhead of 24 bytes to store the related
struct devres_node additionally to the fragmentation of the allocator.
So allocating 16 struct lpc18xx_pwm_data (which only hold a single int)
adds quite some overhead. Instead put the per-channel data into the
driver data struct and allocate it in one go.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
When a driver calls pwmchip_add() it has to be prepared to immediately
get its callbacks called. So move allocation of driver data and hardware
initialization before the call to pwmchip_add().
This fixes a potential NULL pointer exception and a race condition on
register writes.
Fixes: 841e6f90bb ("pwm: NXP LPC18xx PWM/SCT driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The driver tracks per-channel data via struct pwm_device::chip_data and
struct meson_pwm::channels[]. The latter holds the actual data, the former
is only a pointer to the latter. So simplify by using struct
meson_pwm::channels[] consistently.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
In meson_pwm_free() the function pwm_get_chip_data() always returns a
non-NULL pointer because it's only called when the request callback
succeeded and this callback calls pwm_set_chip_data() in this case.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
In .request() pwm_get_chip_data() returns NULL always since commit
e926b12c61 ("pwm: Clear chip_data in pwm_put()"). (And if it didn't
returning 0 would be wrong because then .request() wouldn't reenable
the clk which the other driver code depends on.)
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
When disabling a regulator fails while the device goes away, there is
little we can do and the machine is probably in enough trouble that any
action we'd want to take fails anyhow.
The return value used to be passed on in cs42l51_i2c_remove() (i.e. the
i2c device remove callback). But the i2c core ignores the error code
(apart from emitting a generic warning) and removes the device anyhow.
So return 0 unconditionally in cs42l51_i2c_remove(), and instead of
returning the error code to the upper layer emit a more helpful warning
message. After that nobody is interested any more in the actual error
code, so let cs42l51_remove() return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220110071832.306185-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
The current implementation gets device lifetime tracking wrong. The
problem is that allocation of struct counter_device is controlled by the
individual drivers but this structure contains a struct device that
might have to live longer than a driver is bound. As a result a command
sequence like:
{ sleep 5; echo bang; } > /dev/counter0 &
sleep 1;
echo 40000000.timer:counter > /sys/bus/platform/drivers/stm32-timer-counter/unbind
can keep a reference to the struct device and unbinding results in
freeing the memory occupied by this device resulting in an oops.
This commit provides two new functions (plus some helpers):
- counter_alloc() to allocate a struct counter_device that is
automatically freed once the embedded struct device is released
- counter_add() to register such a device.
Note that this commit doesn't fix any issues, all drivers have to be
converted to these new functions to correct the lifetime problems.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211230150300.72196-14-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Uwe Kleine-König