static int atmel_tcb_pwm_probe()

in pwm-atmel-tcb.c [419:501]

• 67 lines of code
• 11 McCabe index (conditional complexity)

static int atmel_tcb_pwm_probe(struct platform_device *pdev)
{
	const struct of_device_id *match;
	struct atmel_tcb_pwm_chip *tcbpwm;
	const struct atmel_tcb_config *config;
	struct device_node *np = pdev->dev.of_node;
	struct regmap *regmap;
	struct clk *clk, *gclk = NULL;
	struct clk *slow_clk;
	char clk_name[] = "t0_clk";
	int err;
	int channel;

	err = of_property_read_u32(np, "reg", &channel);
	if (err < 0) {
		dev_err(&pdev->dev,
			"failed to get Timer Counter Block channel from device tree (error: %d)\n",
			err);
		return err;
	}

	regmap = syscon_node_to_regmap(np->parent);
	if (IS_ERR(regmap))
		return PTR_ERR(regmap);

	slow_clk = of_clk_get_by_name(np->parent, "slow_clk");
	if (IS_ERR(slow_clk))
		return PTR_ERR(slow_clk);

	clk_name[1] += channel;
	clk = of_clk_get_by_name(np->parent, clk_name);
	if (IS_ERR(clk))
		clk = of_clk_get_by_name(np->parent, "t0_clk");
	if (IS_ERR(clk))
		return PTR_ERR(clk);

	match = of_match_node(atmel_tcb_of_match, np->parent);
	config = match->data;

	if (config->has_gclk) {
		gclk = of_clk_get_by_name(np->parent, "gclk");
		if (IS_ERR(gclk))
			return PTR_ERR(gclk);
	}

	tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL);
	if (tcbpwm == NULL) {
		err = -ENOMEM;
		goto err_slow_clk;
	}

	tcbpwm->chip.dev = &pdev->dev;
	tcbpwm->chip.ops = &atmel_tcb_pwm_ops;
	tcbpwm->chip.npwm = NPWM;
	tcbpwm->channel = channel;
	tcbpwm->regmap = regmap;
	tcbpwm->clk = clk;
	tcbpwm->gclk = gclk;
	tcbpwm->slow_clk = slow_clk;
	tcbpwm->width = config->counter_width;

	err = clk_prepare_enable(slow_clk);
	if (err)
		goto err_slow_clk;

	spin_lock_init(&tcbpwm->lock);

	err = pwmchip_add(&tcbpwm->chip);
	if (err < 0)
		goto err_disable_clk;

	platform_set_drvdata(pdev, tcbpwm);

	return 0;

err_disable_clk:
	clk_disable_unprepare(tcbpwm->slow_clk);

err_slow_clk:
	clk_put(slow_clk);

	return err;
}