> T-HEAD SoCs such as the TH1520 contain a PWM controller used
> to control the LCD backlight, fan and so on. Add driver for it.
>
> Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx > ---
Hello,
I've just tested your driver and it works flawlessly on the
BeagleV-Ahead with the last mainline kernel. However, I had to modify
some portion of the code to comply with the last kernel needs.
> +static const struct pwm_ops thead_pwm_ops = {
> + .apply = thead_pwm_apply,
> + .get_state = thead_pwm_get_state,
> + .owner = THIS_MODULE,
Since commit 384461abcab6, the owner of a pwm_ops structure is implicit
and so, you can (must) remove this last line now.
> +};
> ...
> +static int thead_pwm_probe(struct platform_device *pdev)
> +{
> + struct thead_pwm_chip *priv;
> + int ret, i;
> + u32 val;
> +
> + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + platform_set_drvdata(pdev, priv);
> +
> + priv->mmio_base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(priv->mmio_base))
> + return PTR_ERR(priv->mmio_base);
> +
> + priv->clk = devm_clk_get_enabled(&pdev->dev, NULL);
> + if (IS_ERR(priv->clk))
> + return PTR_ERR(priv->clk);
> +
> + priv->chip.ops = &thead_pwm_ops;
> + priv->chip.dev = &pdev->dev;
> + priv->chip.npwm = THEAD_PWM_MAX_NUM;
> +
> + /* check whether PWM is ever started or not */
> + for (i = 0; i < priv->chip.npwm; i++) {
> + val = readl(priv->mmio_base + THEAD_PWM_FP(i));
> + if (val)
> + priv->channel_ever_started |= 1 << i;
BIT(i) ?
If the bootloader starts a PWM channel for some reason, it will not be
referenced by the PM usage counter, I added this line in the if
statement to counter this problem :
pm_runtime_get(&pdev->dev);
> + }
> +
> + ret = devm_pwmchip_add(&pdev->dev, &priv->chip);
> + if (ret)
> + return ret;
> +
> + devm_pm_runtime_enable(&pdev->dev);
> +
> + return 0;
> +}
Thank you for your work. With the above comments addressed:
Tested-by: Thomas Bonnefille <thomas.bonnefille@xxxxxxxxxxx>
Do you plan to send out a new iteration of this patch soon ?
Best regards,
Thomas Bonnefille
