Re: [PATCH] extcon: arizona: Get pdata from arizona structure notdevice

From: Chanwoo Choi
Date: Mon Sep 30 2013 - 19:14:50 EST


On 10/01/2013 08:04 AM, Chanwoo Choi wrote:
> On 09/30/2013 06:52 PM, Charles Keepax wrote:
>> On Mon, Sep 30, 2013 at 08:37:30AM +0900, Chanwoo Choi wrote:
>>> No, extcon-arizona driver don't currently support DT to get platform data.
>>> I cannot find some dt function to parse data from dts file.
>>> You have to implement extcon-arizona driver by using DT binding style
>>> to get platform data. I think this patch is not necessary.
>>
>> Currently the Arizona MFD driver reads the device tree
>> information and populates the pdata structure, this happens in
>> drivers/mfd/arizona-core.c. Then the various drivers just use the
>> pdata as normal.
>>
>> Admittedly, at the moment we don't parse any data for the extcon
>> driver but without this patch we will attempt to use a NULL
>> pointer on device tree systems.
>>
>> I would also be happy to implement this as a NULL check on the
>> pdata when we use it if that is preferable? But since we have the
>> cached pdata seems we might as well use it.
>>
>
> I find below pdata list for extcon-arizona driver.
> But, drivers/mfd/arizona-core.c don't parse dt data for below pdata list
> of extcon-arizona. Did you test this patch for extcon-arizona operation?
>
> arizona->pdata.micd_pol_gpio
> arizona->pdata.micd_force_micbias
> arizona->pdata.hpdet_id_gpio
> arizona->pdata.hpdet_acc_id
> arizona->pdata.hpdet_acc_id_line
> arizona->pdata.micd_detect_debounce
> arizona->pdata.jd_gpio5
> arizona->pdata.micd_timeout
> arizona->pdata.num_micd_configs
> arizona->pdata.micd_configs
> arizona->pdata.micd_bias_start_time
> arizona->pdata.micd_rate
> arizona->pdata.micd_dbtime
> arizona->pdata.num_micd_ranges
> ...
>
> If you fix NULL pointer error about pdata,
> I think only that extcon-arizona modify it as following:
>
> diff --git a/drivers/extcon/extcon-arizona.c b/drivers/extcon/extcon-arizona.c
> index e557130..3429906 100644
> --- a/drivers/extcon/extcon-arizona.c
> +++ b/drivers/extcon/extcon-arizona.c
> @@ -1088,6 +1088,10 @@ static int arizona_extcon_probe(struct platform_device *pdev)
> return -EPROBE_DEFER;
>
> pdata = dev_get_platdata(arizona->dev);
> + if (!pdata) {
> + dev_err(&pdev->dev, "Failed to get platform data\n");
> + return -EINVAL;
> + }
>
> info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
> if (!info) {
>

Additionally,I have a question.
As I mentioned, extcon-arizon driver don't get pdata from dt parsing.
I think extcon-arizona haven't operated without pdata.

Did you only build test for extcon-arizona?

I'd like you to implement parse function for extcon-arizona
to solve this issue(NULL pointer error).

Thanks
Chanwoo Choi




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