[PATCH v6 1/2] PWM: atmel-pwm: add PWM controller driver
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Thu Nov 14 11:38:17 EST 2013
> >>+MODULE_DEVICE_TABLE(of, atmel_pwm_dt_ids);
> >>+#endif
> >>+
> >>+static int atmel_pwm_probe(struct platform_device *pdev)
> >>+{
> >>+ const struct of_device_id *of_id =
> >>+ of_match_device(atmel_pwm_dt_ids, &pdev->dev);
> >>+ const struct atmel_pwm_data *data;
> >>+ struct atmel_pwm_chip *atmel_pwm;
> >>+ struct resource *res;
> >>+ int ret;
> >>+
> >>+ atmel_pwm = devm_kzalloc(&pdev->dev, sizeof(*atmel_pwm), GFP_KERNEL);
> >>+ if (!atmel_pwm)
> >>+ return -ENOMEM;
> >>+
> >>+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >>+ if (!res)
> >>+ return -ENODEV;
> >>+
> >>+ atmel_pwm->base = devm_ioremap_resource(&pdev->dev, res);
> >>+ if (IS_ERR(atmel_pwm->base))
> >>+ return PTR_ERR(atmel_pwm->base);
> >>+
> >>+ atmel_pwm->clk = devm_clk_get(&pdev->dev, NULL);
> >>+ if (IS_ERR(atmel_pwm->clk))
> >>+ return PTR_ERR(atmel_pwm->clk);
> >>+
> >>+ ret = clk_prepare(atmel_pwm->clk);
> >>+ if (ret) {
> >>+ dev_err(&pdev->dev, "failed to prepare pwm clock\n");
> >>+ return ret;
> >>+ }
> >>+
> >>+ atmel_pwm->chip.dev = &pdev->dev;
> >>+ atmel_pwm->chip.ops = &atmel_pwm_ops;
> >I get one issue here for non-dt platform
>
> I will fix this issue for none-dt in next version.
>
> >>+ atmel_pwm->chip.of_xlate = of_pwm_xlate_with_flags;
> >>+ atmel_pwm->chip.of_pwm_n_cells = 3;
> >those 3 no need
>
> Which "those 3"?
> for dt / none-dt compatible, I will use following code
> --->8---
> if (pdev->dev.of_node) {
> atmel_pwm->chip.of_xlate = of_pwm_xlate_with_flags;
> atmel_pwm->chip.of_pwm_n_cells = 3;
> atmel_pwm->chip.base = -1;
> } else {
> atmel_pwm->chip.base = 0;
base need to choose by the board not 0
> }
> ---8<---
>
> >>+ atmel_pwm->chip.base = -1;
> >here we need specify the base from the board so we known which pwn to use
> >for DT -1 is good as we use phandle
>
> I will fix this issue for none-dt in next version.
>
Best Regards,
J.
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