Re: unbind/bind w1-gpio with device tree produce a crash

From: Ingo Flaschberger
Date: Wed Mar 04 2015 - 11:37:37 EST


is it ok, to create a new global variable that tracks if pdata was alloced via devm_kzalloc and sets pdata to NULL in w1_gpio_remove?

Am 04.03.2015 um 04:53 schrieb Ingo Flaschberger:
If w1-gpio is probed via device-tree configuration, pdata is allocated via devm_kzalloc.
When the device is unbind (and bind later) the allocated memory of pdate is freed - but it will not be allocacted again.

static int w1_gpio_probe(struct platform_device *pdev)
struct w1_bus_master *master;
struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
int err;

if(pdata == NULL) {
if (of_have_populated_dt()) {
err = w1_gpio_probe_dt(pdev);
if (err < 0)
return err;
}
}

How to detect if pdata was allocated via device-tree devm_kzalloc and not "hardcoded"?
Then I could set pdev->dev.platform_data to NULL in w1_gpio_remove which will solve the crash.

Kind regards,
Ingo Flascherger


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