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17 commits

Author SHA1 Message Date
Dong Aisheng dd6c6d57ab pwm: imx-tpm: fix probe crash due to access registers without clock
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>
2024-03-04 11:45:22 +01:00
Uwe Kleine-König abf6569d64 pwm: imx-tpm: Make use of devm_pwmchip_alloc() function
This prepares the pwm-tmp 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.

Link: https://lore.kernel.org/r/5de5d53295fa445d58a79f83421dd3406166c3c6.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2024-02-19 11:04:10 +01:00
Uwe Kleine-König 9676b40e18 pwm: imx-tpm: Use DEFINE_SIMPLE_DEV_PM_OPS for PM functions
This macro has the advantage over SIMPLE_DEV_PM_OPS that we don't have to
care about when the functions are actually used, so the corresponding
__maybe_unused can be dropped.

Also make use of pm_ptr() to discard all PM related stuff if CONFIG_PM
isn't enabled.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2023-12-20 16:04:13 +01:00
Uwe Kleine-König 92fcd5b682 pwm: imx-tpm: Simplify using devm functions
With devm_clk_get_enabled() the call to clk_disable_unprepare() can be
dropped from the error path and the remove callback. With
devm_pwmchip_add() pwmchip_remove() can be dropped. Then the remove
callback is empty and can go away, too.

Also use dev_err_probe() for simplified (and improved) error reporting.

Link: https://lore.kernel.org/r/20230929161918.2410424-5-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2023-10-13 10:07:18 +02:00
Uwe Kleine-König 384461abca pwm: Manage owner assignment implicitly for drivers
Instead of requiring each driver to care for assigning the owner member
of struct pwm_ops, handle that implicitly using a macro. Note that the
owner member has to be moved to struct pwm_chip, as the ops structure
usually lives in read-only memory and so cannot be modified.

The upside is that new low level drivers cannot forget the assignment and
save one line each. The pwm-crc driver didn't assign .owner, that's not
a problem in practice though as the driver cannot be compiled as a
module.

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # Intel LPSS
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> # pwm-{bcm,brcm}*.c
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> # sun4i
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp> # pwm-visconti
Acked-by: Heiko Stuebner <heiko@sntech.de> # pwm-rockchip
Acked-by: Michael Walle <michael@walle.cc> # pwm-sl28cpld
Acked-by: Neil Armstrong <neil.armstrong@linaro.org> # pwm-meson
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230804142707.412137-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2023-10-13 10:07:17 +02:00
Fancy Fang 661dfb7f46 pwm: imx-tpm: force 'real_period' to be zero in suspend
During suspend, all the tpm registers will lose values.
So the 'real_period' value of struct 'imx_tpm_pwm_chip'
should be forced to be zero to force the period update
code can be executed after system resume back.

Signed-off-by: Fancy Fang <chen.fang@nxp.com>
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: 738a1cfec2 ("pwm: Add i.MX TPM PWM driver support")
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2023-06-23 15:42:44 +02:00
Uwe Kleine-König ed60a877af pwm: imx-tpm: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2023-03-30 16:26:30 +02:00
Uwe Kleine-König 6c452cff79 pwm: Make .get_state() callback return an error code
.get_state() might fail in some cases. To make it possible that a driver
signals such a failure change the prototype of .get_state() to return an
error code.

This patch was created using coccinelle and the following semantic patch:

@p1@
identifier getstatefunc;
identifier driver;
@@
 struct pwm_ops driver = {
        ...,
        .get_state = getstatefunc
        ,...
 };

@p2@
identifier p1.getstatefunc;
identifier chip, pwm, state;
@@
-void
+int
 getstatefunc(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state)
 {
   ...
-  return;
+  return 0;
   ...
 }

plus the actual change of the prototype in include/linux/pwm.h (plus some
manual fixing of indentions and empty lines).

So for now all drivers return success unconditionally. They are adapted
in the following patches to make the changes easier reviewable.

Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Acked-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221130152148.2769768-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-12-06 12:46:22 +01:00
Uwe Kleine-König bfecbc9490 pwm: imx-tpm: Don't check the return code of pwmchip_remove()
pwmchip_remove() returns always 0. Don't use the value to make it
possible to eventually change the function to return void. Also the
driver core ignores the return value of pwm_imx_tpm_remove().

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02 21:38:52 +02:00
Uwe Kleine-König e9fdf122cf pwm: Simplify all drivers with explicit of_pwm_n_cells = 3
With the previous commit there is no need for the lowlevel driver any
more to specify it it uses two or three cells. So simplify accordingly.

The only non-trival change affects the pwm-rockchip driver: It used to only
support three cells if the hardware supports polarity. Now the default
number depends on the device tree which has to match hardware anyhow
(and if it doesn't the error is just a bit delayed as a PWM handle with
an inverted setting is catched when pwm_apply_state() is called).

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-05-25 18:19:15 +02:00
Uwe Kleine-König f9a8ee8c8b pwm: Always allocate PWM chip base ID dynamically
Since commit 5e5da1e9fb ("pwm: ab8500: Explicitly allocate pwm chip
base dynamically") all drivers use dynamic ID allocation explicitly. New
drivers are supposed to do the same, so remove support for driver
specified base IDs and drop all assignments in the low-level drivers.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-03-22 11:53:00 +01:00
Fabio Estevam 5a43c201c9 pwm: imx-tpm: Use a single line for error message
There is no need to split the dev_err() call in three lines.

Use a single line to improve readability.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-03-22 11:49:46 +01:00
Anson Huang 168cc32920 pwm: imx-tpm: Use dev_err_probe() to simplify error handling
dev_err_probe() can reduce code size, uniform error handling and record the
defer probe reason etc., use it to simplify the code.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2020-12-17 14:18:47 +01:00
Guru Das Srinagesh fcdea6b2a3 pwm: imx-tpm: Use 64-bit division macro
Since the PWM framework is switching struct pwm_state.period's datatype
to u64, prepare for this transition by using DIV64_U64_ROUND_CLOSEST to
handle a 64-bit divisor.

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2020-06-16 11:16:08 +02:00
Anson Huang c0adbd1cdf pwm: imx-tpm: Remove unused includes
There is nothing in use from log2.h/of_address.h, remove them.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2020-03-30 16:55:26 +02:00
Uwe Kleine-König 71523d1812 pwm: Ensure pwm_apply_state() doesn't modify the state argument
It is surprising for a PWM consumer when the variable holding the
requested state is modified by pwm_apply_state(). Consider for example a
driver doing:

        #define PERIOD 5000000
        #define DUTY_LITTLE 10
        ...
        struct pwm_state state = {
                .period = PERIOD,
                .duty_cycle = DUTY_LITTLE,
                .polarity = PWM_POLARITY_NORMAL,
                .enabled = true,
        };

        pwm_apply_state(mypwm, &state);
        ...
        state.duty_cycle = PERIOD / 2;
        pwm_apply_state(mypwm, &state);

For sure the second call to pwm_apply_state() should still have
state.period = PERIOD and not something the hardware driver chose for a
reason that doesn't necessarily apply to the second call.

So declare the state argument as a pointer to a const type and adapt all
drivers' .apply callbacks.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 03:25:10 +02:00
Anson Huang 738a1cfec2 pwm: Add i.MX TPM PWM driver support
i.MX7ULP has TPM(Low Power Timer/Pulse Width Modulation Module) inside,
it can support multiple PWM channels, all the channels share same
counter and period setting, but each channel can configure its duty and
polarity independently.

There are several TPM modules in i.MX7ULP, the number of channels in TPM
modules are different, it can be read from each TPM module's PARAM
register.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-05-09 17:01:48 +02:00