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

From: Philipp Zabel
Date: Thu Jan 02 2020 - 07:06:55 EST


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@xxxxxxxxxxxx>
> ---
> 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