Re: [PATCH] PWM: imx: pwm-imx-tpm: Add driver support

[Sascha Hauer <s.hauer@pengutronix.de>]

On Sun, Jan 26, 2025 at 10:39:30PM +0100, Michael Grzeschik wrote:
> Import the Linux v6.12 state of the driver to enable barebox control of PWM
> LEDs, backlights and other peripherals.
> 
> This has been tested on the IMX93.
> 
> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
> ---
> +static int pwm_imx_tpm_probe(struct device *dev)
> +{
> +	struct pwm_chip *chip;
> +	struct imx_tpm_pwm *tpm;
> +	struct clk *clk;
> +	void __iomem *base;
> +	int ret;
> +	unsigned int npwm;
> +	u32 val;
> +	int i;
> +
> +	base = dev_platform_ioremap_resource(dev, 0);
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
> +	clk = clk_get_enabled(dev, NULL);
> +	if (IS_ERR(clk))
> +		return dev_err_probe(dev, PTR_ERR(clk),
> +				     "failed to get PWM clock\n");
> +
> +	/* get number of channels */
> +	val = readl(base + PWM_IMX_TPM_PARAM);
> +	npwm = FIELD_GET(PWM_IMX_TPM_PARAM_CHAN, val);
> +
> +	tpm = xzalloc(sizeof(*tpm));
> +	if (IS_ERR(tpm))
> +		return PTR_ERR(tpm);

xzalloc never returns an error (and if it would, it would likely be
NULL)

> +
> +	for (i = 0; i < npwm; i++) {
> +		struct imx_tpm_pwm_chip *tpmc = &tpm->pwm[i];

check npwm against ARRAY_SIZE(tpm->pwm)?

> +
> +		chip = &tpmc->chip;
> +
> +		tpmc->tpm = tpm;
> +		tpmc->tpm->base = base;
> +		tpmc->tpm->clk = clk;
> +
> +		chip->ops = &imx_tpm_pwm_ops;
> +		chip->devname = basprintf("pwm%d", i);

Use xasprintf() when not checking for an error.

Sascha

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