Re: [PATCH v5 3/8] mailbox: sun6i-msgbox: Add a new mailbox driver

[Philipp Zabel <p.zabel@pengutronix.de>]

On Sat, 2019-12-14 at 22:24 -0600, Samuel Holland wrote:
> Allwinner sun6i, sun8i, sun9i, and sun50i SoCs contain a hardware
> message box used for communication between the ARM CPUs and the ARISC
> management coprocessor. This mailbox contains 8 unidirectional
> 4-message FIFOs.
> 
> Add a driver for it, so it can be used for SCPI or other communication
> protocols.
> 
> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
>  drivers/mailbox/Kconfig        |   9 +
>  drivers/mailbox/Makefile       |   2 +
>  drivers/mailbox/sun6i-msgbox.c | 332 +++++++++++++++++++++++++++++++++
>  3 files changed, 343 insertions(+)
>  create mode 100644 drivers/mailbox/sun6i-msgbox.c
> 
[...]
> diff --git a/drivers/mailbox/sun6i-msgbox.c b/drivers/mailbox/sun6i-msgbox.c
> new file mode 100644
> index 000000000000..7a41e732457c
> --- /dev/null
> +++ b/drivers/mailbox/sun6i-msgbox.c
> @@ -0,0 +1,332 @@
[...]
> +static int sun6i_msgbox_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct mbox_chan *chans;
> +	struct reset_control *reset;
> +	struct resource *res;
> +	struct sun6i_msgbox *mbox;
> +	int i, ret;
> +
> +	mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
> +	if (!mbox)
> +		return -ENOMEM;
> +
> +	chans = devm_kcalloc(dev, NUM_CHANS, sizeof(*chans), GFP_KERNEL);
> +	if (!chans)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < NUM_CHANS; ++i)
> +		chans[i].con_priv = mbox;
> +
> +	mbox->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(mbox->clk)) {
> +		ret = PTR_ERR(mbox->clk);
> +		dev_err(dev, "Failed to get clock: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(mbox->clk);
> +	if (ret) {
> +		dev_err(dev, "Failed to enable clock: %d\n", ret);
> +		return ret;
> +	}
> +
> +	reset = devm_reset_control_get(dev, NULL);

Please use devm_reset_control_get_exclusive() explicitly.

regards
Philipp