Re: [PATCH RESEND v3] mwifiex: parse device tree node for PCIe

[Brian Norris <briannorris-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>]

Hi,

On Thu, Sep 29, 2016 at 10:09:43PM +0530, Amitkumar Karwar wrote:
> From: Xinming Hu <huxm-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
> 
> This patch derives device tree node from pcie bus layer framework.
> Device tree bindings file has been renamed(marvell-sd8xxx.txt ->
> marvell-8xxx.txt) to accomodate PCIe changes.
> 
> Signed-off-by: Xinming Hu <huxm-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
> Signed-off-by: Amitkumar Karwar <akarwar-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
> ---
> v2: Included vendor and product IDs in compatible strings for PCIe
> chipsets(Rob Herring)
> v3: Patch is created using -M option so that it will only include diff of
> original and renamed files(Rob Herring)
> Resend v3: Resending the patch because I missed to include device tree mailing
> while sending v3.
> ---

Why is this patch so different than the SDIO DT handling for the same
driver?

>  .../{marvell-sd8xxx.txt => marvell-8xxx.txt}         |  8 +++++---
>  drivers/net/wireless/marvell/mwifiex/pcie.c          | 20 ++++++++++++++++++++
>  drivers/net/wireless/marvell/mwifiex/sta_cmd.c       |  3 ++-
>  3 files changed, 27 insertions(+), 4 deletions(-)
>  rename Documentation/devicetree/bindings/net/wireless/{marvell-sd8xxx.txt => marvell-8xxx.txt} (91%)
> 
> diff --git a/Documentation/devicetree/bindings/net/wireless/marvell-sd8xxx.txt b/Documentation/devicetree/bindings/net/wireless/marvell-8xxx.txt
> similarity index 91%
> rename from Documentation/devicetree/bindings/net/wireless/marvell-sd8xxx.txt
> rename to Documentation/devicetree/bindings/net/wireless/marvell-8xxx.txt
> index c421aba..dfe5f8e 100644
> --- a/Documentation/devicetree/bindings/net/wireless/marvell-sd8xxx.txt
> +++ b/Documentation/devicetree/bindings/net/wireless/marvell-8xxx.txt
> @@ -1,8 +1,8 @@
> -Marvell 8897/8997 (sd8897/sd8997) SDIO devices
> +Marvell 8897/8997 (sd8897/sd8997/pcie8997) SDIO/PCIE devices
>  ------
>  
> -This node provides properties for controlling the marvell sdio wireless device.
> -The node is expected to be specified as a child node to the SDIO controller that
> +This node provides properties for controlling the marvell sdio/pcie wireless device.
> +The node is expected to be specified as a child node to the SDIO/PCIE controller that
>  connects the device to the system.
>  
>  Required properties:
> @@ -10,6 +10,8 @@ Required properties:
>    - compatible : should be one of the following:
>  	* "marvell,sd8897"
>  	* "marvell,sd8997"
> +	* "pci11ab,2b42"
> +	* "pci1b4b,2b42"
>  
>  Optional properties:
>  
> diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
> index 063c707..f1eeb73 100644
> --- a/drivers/net/wireless/marvell/mwifiex/pcie.c
> +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
> @@ -37,6 +37,23 @@ static struct mwifiex_if_ops pcie_ops;
>  
>  static struct semaphore add_remove_card_sem;
>  
> +static const struct of_device_id mwifiex_pcie_of_match_table[] = {
> +	{ .compatible = "pci11ab,2b42" },
> +	{ .compatible = "pci1b4b,2b42" },
> +	{ }
> +};
> +
> +static int mwifiex_pcie_probe_of(struct device *dev)
> +{
> +	if (!dev->of_node ||

In sdio.c, this check is done silently; that way, we don't error out
(and print an error string) just because there's no DT node. And I think
that makes sense.

Maybe pull this condition out separately and return 0?

> +	    !of_match_node(mwifiex_pcie_of_match_table, dev->of_node)) {
> +		pr_err("pcie device node not available");
> +		return -1;
> +	}
> +

Just an FYI, the equivalent sdio.c code (mwifiex_sdio_probe_of()) also
parses a platform-specific wakeup pin. Rajat and I were considering
moving that to mwifiex_register(), so we can get the same handling in
pcie.c. But I think it's probably sane to leave the compatible table
here in the interface driver for now.

> +	return 0;
> +}
> +
>  static int
>  mwifiex_map_pci_memory(struct mwifiex_adapter *adapter, struct sk_buff *skb,
>  		       size_t size, int flags)
> @@ -206,6 +223,9 @@ static int mwifiex_pcie_probe(struct pci_dev *pdev,
>  		card->pcie.can_ext_scan = data->can_ext_scan;
>  	}
>  
> +	/* device tree node parsing and platform specific configuration*/
> +	mwifiex_pcie_probe_of(&pdev->dev);

You aren't catching the error code here. Probably because you're wrongly
returning an error above for the !of_node case.

Brian

> +
>  	if (mwifiex_add_card(card, &add_remove_card_sem, &pcie_ops,
>  			     MWIFIEX_PCIE)) {
>  		pr_err("%s failed\n", __func__);
> diff --git a/drivers/net/wireless/marvell/mwifiex/sta_cmd.c b/drivers/net/wireless/marvell/mwifiex/sta_cmd.c
> index 638d30a..f2a7a13 100644
> --- a/drivers/net/wireless/marvell/mwifiex/sta_cmd.c
> +++ b/drivers/net/wireless/marvell/mwifiex/sta_cmd.c
> @@ -2218,7 +2218,8 @@ int mwifiex_sta_init_cmd(struct mwifiex_private *priv, u8 first_sta, bool init)
>  		 * The cal-data can be read from device tree and/or
>  		 * a configuration file and downloaded to firmware.
>  		 */
> -		if (priv->adapter->iface_type == MWIFIEX_SDIO &&
> +		if ((priv->adapter->iface_type == MWIFIEX_SDIO ||
> +		    priv->adapter->iface_type == MWIFIEX_PCIE) &&
>  		    adapter->dev->of_node) {
>  			adapter->dt_node = adapter->dev->of_node;
>  			if (of_property_read_u32(adapter->dt_node,