stm32_pwm_config() took the duty_cycle and period values with the type
int, however stm32_pwm_apply() passed u64 values there. Expand the
function parameters to u64 to not discard relevant bits and adapt the
calculations to the wider type.
To ensure the calculations won't overflow, check in .probe() the input
clk doesn't run faster than 1 GHz.
Link: https://lore.kernel.org/r/06b4a650a608d0887d934c1b2b8919e0f78e4db2.1710711976.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
While mathematically it's ok to calculate the number of cyles for the
duty cycle as:
duty_cycles = period_cycles * duty_ns / period_ns
this doesn't always give the right result when doing integer math. This
is best demonstrated using an example: With the input clock running at
208877930 Hz a request for duty_cycle = 383 ns and period = 49996 ns
results in
period_cycles = clkrate * period_ns / NSEC_PER_SEC = 10443.06098828
Now calculating duty_cycles with the above formula gives:
duty_cycles = 10443.06098828 * 383 / 49996 = 80.00024719
However with period_cycle truncated to an integer results in:
duty_cycles = 10443 * 383 / 49996 = 79.99977998239859
So while a value of (a little more than) 80 would be the right result,
only 79 is used here. The problem here is that 14443 is a rounded result
that should better not be used to do further math. So to fix that use
the exact formular similar to how period_cycles is calculated.
Link: https://lore.kernel.org/r/7628ecd8a7538aa5a7397f0fc4199a077168e8a6.1710711976.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Giving an indication about the problem if probing a device fails is a
nice move. Do that for the stm32 pwm driver.
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20240315145443.982807-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
After assigning chip = pwm->chip; the compiler is free to assume that
pwm is non-NULL and so can optimize out the check for pwm against NULL.
While it's probably a programming error to pass a NULL pointer to
pwm_put() this shouldn't be dropped without careful consideration and
wasn't intended.
So assign chip only after the NULL check.
Reported-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/66a6f562-1fdd-4e45-995a-e7995432aa0c@baylibre.com
Fixes: 4c56b1434b ("pwm: Add a struct device to struct pwm_chip")
Link: https://lore.kernel.org/r/20240329101648.544155-2-u.kleine-koenig@pengutronix.de
Reviewed-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
It's required to not free the memory underlying a requested PWM
while a consumer still has a reference to it. While currently a pwm_chip
doesn't live long enough in all cases, linking the struct pwm to the
pwm_chip results in the right lifetime as soon as the pwmchip is living
long enough. This happens with the following commits.
Note this is a breaking change for all pwm drivers that don't use
pwmchip_alloc().
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> # for struct_size() and __counted_by()
Link: https://lore.kernel.org/r/7e9e958841f049026c0023b309cc9deecf0ab61d.1710670958.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
With the upcoming restructuring having all in a single file simplifies
things a bit. The relevant and somewhat visible changes are:
- Some dropped prototypes from include/linux/pwm.h that were only
necessary that core.c has a declaration of the symbols defined in
sysfs.c. The respective functions are static now.
- The pwm class now also exists if CONFIG_SYSFS isn't enabled. Having
CONFIG_SYSFS is not very relevant today, but even without it the
class and device stuff still provides lifetime tracking.
- Both files had an initcall, these are merged into a single one now.
Instead of a big #ifdef block for CONFIG_DEBUG_FS, a single
if (IS_ENABLED(CONFIG_DEBUG_FS)) is used now. This increases compile
coverage a bit and is a tad nicer on the eyes.
Link: https://lore.kernel.org/r/9e2d39a5280d7dda5bfc6682a8aef510148635b2.1710670958.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
The code handling the sysfs API uses "child" and "parent" to refer to
the devices corresponding to a struct pwm or a struct pwm_chip
respectively.
Other parts of the pwm core use "parent" to refer to the parent device of
a struct pwm_chip.
So rename "child" to "pwm_dev" and "parent" to "pwmchip_dev" which
better explains the semantic. Also two functions are changed to match
the new names:
child_to_pwm_export() -> pwmexport_from_dev()
child_to_pwm_device() -> pwm_from_dev()
(which have the additional advantage to start with "pwm" which gives the
right scope). Additionally introduce a wrapper for dev_get_drvdata() to
convert a pwmchip_dev to the respective pwm_chip.
Link: https://lore.kernel.org/r/9cc05aceeae2f06ecb850bccb15ba821e768c183.1710670958.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
While the compiler probably optimizes out the pointer dereference, using
the local variable holding the same value also benefits the human
reader. So simplify accordingly. Also move a loop over all capture lines
into the capture if block to group the operations related to capturing
in .probe().
Link: https://lore.kernel.org/r/a7a81f3838f7ed7f4d6dbee3d646989cc265f676.1710068192.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This has the advantage of handling EPROBE_DEFER correctly and being more
compact.
This change also introduces an error message for a few error paths that
lacked an error indicator before. Also sti_pwm_probe_dt() is renamed to
sti_pwm_probe_regmap() to better fit what it actually does.
Link: https://lore.kernel.org/r/8e540733ab882f2b8873712faf85c4f0cb48133a.1710068192.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Instead of of_clk_get_by_name() use devm_clk_get_prepared() which has
several advantages:
- Combines getting the clock and a call to clk_prepare(). The latter
can be dropped from sti_pwm_probe() accordingly.
- Cares for calling clk_put() which is missing in both probe's error
path and the remove function.
- Cares for calling clk_unprepare() which can be dropped from the error
paths and the remove function. (Note that not all error path got this
right.)
With additionally using devm_pwmchip_add() instead of pwmchip_add() the
remove callback can be dropped completely. With it the last user of
platform_get_drvdata() goes away and so platform_set_drvdata() can be
dropped from the probe function, too.
Fixes: 378fe115d1 ("pwm: sti: Add new driver for ST's PWM IP")
Link: https://lore.kernel.org/r/81f0e1d173652f435afda6719adaed1922fe059a.1710068192.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Memory holding a struct device must not be freed before the reference
count drops to zero. So a struct pwm_chip must not live in memory
freed by a driver on unbind. All in-tree drivers were fixed accordingly,
but as out-of-tree drivers, that were not adapted, still compile fine,
catch these in pwmchip_add().
Link: https://lore.kernel.org/r/35f5b229c98f78b2f6ce2397259a4a936be477c0.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
With 16 channel pwm support, we're registering two instances of pwm_chip
with 8 channels each. We need to update PM functions to use both instances
of pwm_chip during power state transitions.
Introduce struct dwc_pwm_drvdata and use it as driver_data, which will
maintain both instances of pwm_chip along with dwc_pwm_info and allow us
to use them inside suspend/resume handles.
Fixes: ebf2c89eb9 ("pwm: dwc: Add 16 channel support for Intel Elkhart Lake")
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240415074051.14681-1-raag.jadav@intel.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
22e8e19 has introduced a regression in the imgchip->pwm_clk lookup, whereas
the clock name has also been renamed to "imgchip". This causes the driver
failing to load:
[ 0.546905] img-pwm 18101300.pwm: failed to get imgchip clock
[ 0.553418] img-pwm: probe of 18101300.pwm failed with error -2
Fix this lookup by reverting the clock name back to "pwm".
Signed-off-by: Zoltan HERPAI <wigyori@uid0.hu>
Link: https://lore.kernel.org/r/20240320083602.81592-1-wigyori@uid0.hu
Fixes: 22e8e19a46 ("pwm: img: Rename variable pointing to driver private data")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
The following commit abf6569d64 ("pwm: imx-tpm: Make use of
devm_pwmchip_alloc() function") introduced an issue that accessing
registers without clock which results in the following boot crash
on MX7ULP platform. Fixed it by enabling clock properly.
Unhandled fault: external abort on non-linefetch (0x1008) at 0xf0978004
[f0978004] *pgd=64009811, *pte=40250653, *ppte=40250453
Internal error: : 1008 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.8.0-rc6-next-20240301 #18
Hardware name: Freescale i.MX7ULP (Device Tree)
PC is at pwm_imx_tpm_probe+0x1c/0xd8
LR is at __devm_ioremap_resource+0xf8/0x1dc
pc : [<c0629e58>] lr : [<c0562d4c>] psr: 80000053
sp : f0825e10 ip : 00000000 fp : 00000000
r10: c148f8c0 r9 : c41fc338 r8 : c164b000
r7 : 00000000 r6 : c406b400 r5 : c406b410 r4 : f0978000
r3 : 00000005 r2 : 00000000 r1 : a0000053 r0 : f0978000
Flags: Nzcv IRQs on FIQs off Mode SVC_32 ISA ARM Segment none
Control: 10c5387d Table: 6000406a DAC: 00000051
...
Call trace:
pwm_imx_tpm_probe from platform_probe+0x58/0xb0
platform_probe from really_probe+0xc4/0x2e0
really_probe from __driver_probe_device+0x84/0x19c
__driver_probe_device from driver_probe_device+0x2c/0x104
driver_probe_device from __driver_attach+0x90/0x170
__driver_attach from bus_for_each_dev+0x7c/0xd0
bus_for_each_dev from bus_add_driver+0xc4/0x1cc
bus_add_driver from driver_register+0x7c/0x114
driver_register from do_one_initcall+0x58/0x270
do_one_initcall from kernel_init_freeable+0x170/0x218
kernel_init_freeable from kernel_init+0x14/0x140
kernel_init from ret_from_fork+0x14/0x20
Fixes: abf6569d64 ("pwm: imx-tpm: Make use of devm_pwmchip_alloc() function")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Link: https://lore.kernel.org/r/20240304102929.893542-1-aisheng.dong@nxp.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Meson8 pwm type always has 4 input clocks. Some inputs may be grounded,
like in the AO domain of some SoCs.
Drop the parent number parameter and make this is constant.
This is also done to make the addition of generic meson8 compatible easier.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20240221151154.26452-4-jbrunet@baylibre.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Simplify error handling in ->probe() function using dev_err_probe() helper
and while at it, drop error codes from the message to prevent duplication.
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240219033835.11369-5-raag.jadav@intel.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Intel Elkhart Lake PSE includes two instances of PWM as a single PCI
function with 8 channels each. Add support for the remaining channels.
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Lakshmi Sowjanya D <lakshmi.sowjanya.d@intel.com>
Link: https://lore.kernel.org/r/20240219033835.11369-4-raag.jadav@intel.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
pcim_iomap_table() fails only if pcim_iomap_regions() fails. No need to
check for failure if the latter is already successful.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240219033835.11369-3-raag.jadav@intel.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This prepares the pwm-vt8500 driver to further changes of the pwm core
outlined in the commit introducing devm_pwmchip_alloc(). There is no
intended semantical change and the driver should behave as before.
Also convert the to_vt8500_chip() helper macro to a static inline to
get some type safety.
Link: https://lore.kernel.org/r/b203c4448db23ebad1165b7bce43ac41468c4e89.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This prepares the driver for further changes that will make it harder to
determine the pwm_chip from a given ehrpwm_pwm_chip. To just not have to
do that, rework ehrpwm_pwm_save_context() and
ehrpwm_pwm_restore_context() take a pwm_chip. Also use the pwm_chip as
driver data instead of the ehrpwm_pwm_chip.
Link: https://lore.kernel.org/r/79052207cdf71f0882ae13fe1a192ef6f6dba35b.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This prepares the driver for further changes that will make it harder to
determine the pwm_chip from a given ecap_pwm_chip. To just not have to
do that, rework ecap_pwm_save_context() and ecap_pwm_restore_context
take a pwm_chip. Also use the pwm_chip as driver data instead of the
ecap_pwm_chip.
Link: https://lore.kernel.org/r/ed031f201ff52c6b298de2dc81b06aad3a0207f8.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
