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path: root/drivers/pwm/pwm-lpc18xx-sct.c
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* pwm: lpc18xx-sct: Don't reconfigure PWM in .request and .freeUwe Kleine-König2018-11-161-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | Regarding the .request case: The consumer might be interested in taking over the configured state from the boot loader. So the initially configured state should be retained. For the free case the PWM consumer is responsible for disabling the PWM before calling pwm_put() and there are three subcases to consider: a) The PWM is already off. Then there is no gain in disabling the PWM once more. b) The PWM is still running and there is a good reason for that. (Not sure this is a valid case, I cannot imagine such a good reason.) Then it is counterproductive to disable the PWM. c) The PWM is still running because the consumer failed to disable the PWM. Then the consumer needs fixing and there is little incentive to paper over the problem in the backend driver. This aligns the lpc18xx-sct driver to the other PWM drivers that also don't reconfigure the hardware in .request and .free. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: lpc-18xx: use pwm_set_chip_dataoliver@schinagl.nl2016-09-081-4/+8
| | | | | | | | | | | The lpc-18xx driver currently manipulates the pwm_device struct directly rather than using the pwm_set_chip_data() function. While the current method may save a clock cycle or two, using the explicit function call makes it more obvious that data is set to the local chip data pointer. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Reviewed-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: Use pwm_get/set_xxx() helpers where appropriateBoris Brezillon2016-05-171-1/+1
| | | | | | | | | Use pwm_get/set_xxx() helpers instead of directly accessing the pwm->xxx field. Doing that will ease adaptation of the PWM framework to support atomic update. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: lpc18xx-sct: Test clock rate to avoid division by 0Wolfram Sang2016-03-231-0/+5
| | | | | | | | | The clk API may return 0 on clk_get_rate(), so we should check the result before using it as a divisor. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Joachim Eastwood <manabian@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: NXP LPC18xx PWM/SCT driverAriel D'Alessandro2015-09-091-0/+465
This commit adds support for NXP LPC18xx PWM/SCT. NXP LPC SoCs family, which includes LPC18xx/LPC43xx, provides a State Configurable Timer (SCT) which can be configured as a Pulse Width Modulator. Other SoCs in that family may share the same hardware. The PWM supports a total of 16 channels, but only 15 can be simultaneously requested. There's only one period, global to all the channels, thus PWM driver will refuse setting different values to it, unless there's only one channel requested. Signed-off-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar> [thierry.reding@gmail.com: remove excessive padding of fields] Signed-off-by: Thierry Reding <thierry.reding@gmail.com>