Re: [PATCH v5 1/6] ARM: at91: add TCB registers definitions

From: Daniel Lezcano
Date: Thu Jun 28 2018 - 11:15:43 EST


On 19/06/2018 23:19, Alexandre Belloni wrote:
> Add registers and bits definitions for the timer counter blocks found on
> Atmel ARM SoCs.
>
> Tested-by: Alexander Dahl <ada@xxxxxxxxxxx>
> Tested-by: Andras Szemzo <szemzo.andras@xxxxxxxxx>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> ---
> include/soc/at91/atmel_tcb.h | 216 +++++++++++++++++++++++++++++++++++

Is the header necessary ? Can it be moved in the .c ?

> 1 file changed, 216 insertions(+)
> create mode 100644 include/soc/at91/atmel_tcb.h
>
> diff --git a/include/soc/at91/atmel_tcb.h b/include/soc/at91/atmel_tcb.h
> new file mode 100644
> index 000000000000..3ed66031fc76
> --- /dev/null

[ ... ]

> +static inline struct clk *tcb_clk_get(struct device_node *node, int channel)
> +{
> + struct clk *clk;
> + char clk_name[] = "t0_clk";
> +
> + clk_name[1] += channel;

clever :)

> + clk = of_clk_get_by_name(node->parent, clk_name);
> + if (!IS_ERR(clk))
> + return clk;
> +
> + return of_clk_get_by_name(node->parent, "t0_clk");

Why do you want to return clk from t0_clk if another channel is
requested ? This is prone to error.

I would clarify that at the caller level, if tcb_clk_get fails then try
with channel zero.

> +}
> +
> +static inline int tcb_irq_get(struct device_node *node, int channel)

no inline

> +{
> + int irq;
> +
> + irq = of_irq_get(node->parent, channel);
> + if (irq > 0)
> + return irq;
> +
> + return of_irq_get(node->parent, 0);

Same comment than above.

> +}
> +
> +static const u8 atmel_tc_divisors[5] = { 2, 8, 32, 128, 0, };
> +
> +struct atmel_tcb_info {
> + int bits;
> +};
> +
> +static const struct atmel_tcb_info atmel_tcb_infos[] = {
> + { .bits = 16 },
> + { .bits = 32 },
> +};

Structuring the code with structure is a good practice. However, this is
too much :)

> +static const struct of_device_id atmel_tcb_dt_ids[] = {
> + {
> + .compatible = "atmel,at91rm9200-tcb",
> + .data = &atmel_tcb_infos[0],

.data = (void *)16;

> + }, {
> + .compatible = "atmel,at91sam9x5-tcb",
> + .data = &atmel_tcb_infos[1],
> + }, {
> + /* sentinel */
> + }
> +};
> +



> +#endif /* __SOC_ATMEL_TCB_H */
>


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