Commit 5bb0b194 authored by Uwe Kleine-König's avatar Uwe Kleine-König
Browse files

pwm: sti: Simplify probe function using devm functions 

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: 378fe115 ("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: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
parent 4bda9700

drivers/pwm/pwm-sti.c

+3 −36
Original line number Diff line number Diff line
@@ -624,32 +624,20 @@ static int sti_pwm_probe(struct platform_device *pdev) 
		return ret;



	if (cdata->pwm_num_devs) {

		pc->pwm_clk = of_clk_get_by_name(dev->of_node, "pwm");

		pc->pwm_clk = devm_clk_get_prepared(dev, "pwm");

		if (IS_ERR(pc->pwm_clk)) {

			dev_err(dev, "failed to get PWM clock\n");

			return PTR_ERR(pc->pwm_clk);

		}



		ret = clk_prepare(pc->pwm_clk);

		if (ret) {

			dev_err(dev, "failed to prepare clock\n");

			return ret;

		}

	}



	if (cdata->cpt_num_devs) {

		pc->cpt_clk = of_clk_get_by_name(dev->of_node, "capture");

		pc->cpt_clk = devm_clk_get_prepared(dev, "capture");

		if (IS_ERR(pc->cpt_clk)) {

			dev_err(dev, "failed to get PWM capture clock\n");

			return PTR_ERR(pc->cpt_clk);

		}



		ret = clk_prepare(pc->cpt_clk);

		if (ret) {

			dev_err(dev, "failed to prepare clock\n");

			return ret;

		}



		cdata->ddata = devm_kzalloc(dev, cdata->cpt_num_devs * sizeof(*cdata->ddata), GFP_KERNEL);

		if (!cdata->ddata)

			return -ENOMEM;
@@ -664,27 +652,7 @@ static int sti_pwm_probe(struct platform_device *pdev) 
		mutex_init(&ddata->lock);

	}



	ret = pwmchip_add(chip);

	if (ret < 0) {

		clk_unprepare(pc->pwm_clk);

		clk_unprepare(pc->cpt_clk);

		return ret;

	}



	platform_set_drvdata(pdev, chip);



	return 0;

}



static void sti_pwm_remove(struct platform_device *pdev)

{

	struct pwm_chip *chip = platform_get_drvdata(pdev);

	struct sti_pwm_chip *pc = to_sti_pwmchip(chip);



	pwmchip_remove(chip);



	clk_unprepare(pc->pwm_clk);

	clk_unprepare(pc->cpt_clk);

	return devm_pwmchip_add(dev, chip);

}



static const struct of_device_id sti_pwm_of_match[] = {
@@ -699,7 +667,6 @@ static struct platform_driver sti_pwm_driver = { 
		.of_match_table = sti_pwm_of_match,

	},

	.probe = sti_pwm_probe,

	.remove_new = sti_pwm_remove,

};

module_platform_driver(sti_pwm_driver);