summaryrefslogtreecommitdiff
path: root/drivers/pwm/pwm-sifive.c
AgeCommit message (Collapse)AuthorFilesLines
2022-08-21pwm: sifive: Shut down hardware only after pwmchip_remove() completedUwe Kleine-König1-2/+3
[ Upstream commit 2375e964d541bb09158cd2dff67b5d74e8de61cd ] The PWMs are expected to be functional until pwmchip_remove() is called. So disable the clks only afterwards. Fixes: 9e37a53eb051 ("pwm: sifive: Add a driver for SiFive SoC PWM") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21pwm: sifive: Ensure the clk is enabled exactly once per running PWMUwe Kleine-König1-9/+37
[ Upstream commit ace41d7564e655c39f709a78c035188a460c7cbd ] .apply() assumes the clk to be for a given PWM iff the PWM is enabled. So make sure this is the case when .probe() completes. And in .remove() disable the according number of times. This fixes a clk enable/disable imbalance, if some PWMs are already running at probe time. Fixes: 9e37a53eb051 (pwm: sifive: Add a driver for SiFive SoC PWM) Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21pwm: sifive: Simplify offset calculation for PWMCMP registersUwe Kleine-König1-7/+3
[ Upstream commit 20550a61880fc55e68a0d290ad195b74729c0e7b ] Instead of explicitly using PWM_SIFIVE_PWMCMP0 + pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP for each access to one of the PWMCMP registers, introduce a macro that takes the hwpwm id as parameter. For the register definition using a plain 4 instead of the cpp constant PWM_SIFIVE_SIZE_PWMCMP is easier to read, so define the offset macro without the constant. The latter can then be dropped as there are no users left. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21pwm: sifive: Don't check the return code of pwmchip_remove()Uwe Kleine-König1-3/+3
[ Upstream commit ceb2c2842f3664dcc4e6d8cb317e1e83bb81b1e5 ] 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_sifive_remove(). Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-24pwm: sifive: Simplify with dev_err_probe()Krzysztof Kozlowski1-5/+3
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> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2020-06-17pwm: sifive: Use 64-bit division macroGuru Das Srinagesh1-1/+1
Since the PWM framework is switching struct pwm_args.period's datatype to u64, prepare for this transition by using DIV64_U64_ROUND_CLOSEST to handle a 64-bit divisor. Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21pwm: Ensure pwm_apply_state() doesn't modify the state argumentUwe Kleine-König1-1/+1
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>
2019-09-21pwm: sifive: Remove redundant error messageDing Xiang1-3/+1
devm_ioremap_resource() already outputs an error message, so remove the extra error message on failure. Signed-off-by: Ding Xiang <dingxiang@cmss.chinamobile.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-06-25pwm: sifive: Add a driver for SiFive SoC PWMYash Shah1-0/+339
Adds a PWM driver for PWM chip present in SiFive's HiFive Unleashed SoC. Signed-off-by: Wesley W. Terpstra <wesley@sifive.com> [Atish: Various fixes and code cleanup] Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Yash Shah <yash.shah@sifive.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>