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

From: Chanwoo Choi
Date: Mon Sep 30 2013 - 19:04:30 EST


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) {

Thanks,
Chanwoo Choi
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