Commit 9925aa4b authored by Théo Lebrun's avatar Théo Lebrun Committed by Greg Kroah-Hartman
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usb: cdns3-ti: run HW init at resume() if HW was reset 



At runtime_resume(), read the W1 (Wrapper Register 1) register to detect
if an hardware reset occurred. If it did, run the hardware init sequence.

This callback will be called at system-wide resume. Previously, if a
reset occurred during suspend, we would crash. The wrapper config had
not been written, leading to invalid register accesses inside cdns3.

Signed-off-by: default avatarThéo Lebrun <theo.lebrun@bootlin.com>
Link: https://lore.kernel.org/r/20250205-s2r-cdns-v7-6-13658a271c3c@bootlin.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 24346dc2

drivers/usb/cdns3/cdns3-ti.c

+25 −0
Original line number Diff line number Diff line
@@ -186,6 +186,12 @@ static int cdns_ti_probe(struct platform_device *pdev) 
	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");

	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");



	/*

	 * The call below to pm_runtime_get_sync() MIGHT reset hardware, if it

	 * detects it as uninitialised. We want to enforce a reset at probe,

	 * and so do it manually here. This means the first runtime_resume()

	 * will be a no-op.

	 */

	cdns_ti_reset_and_init_hw(data);



	pm_runtime_enable(dev);
@@ -230,6 +236,24 @@ static void cdns_ti_remove(struct platform_device *pdev) 
	platform_set_drvdata(pdev, NULL);

}



static int cdns_ti_runtime_resume(struct device *dev)

{

	const u32 mask = USBSS_W1_PWRUP_RST | USBSS_W1_MODESTRAP_SEL;

	struct cdns_ti *data = dev_get_drvdata(dev);

	u32 w1;



	w1 = cdns_ti_readl(data, USBSS_W1);

	if ((w1 & mask) != mask)

		cdns_ti_reset_and_init_hw(data);



	return 0;

}



static const struct dev_pm_ops cdns_ti_pm_ops = {

	RUNTIME_PM_OPS(NULL, cdns_ti_runtime_resume, NULL)

	SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)

};



static const struct of_device_id cdns_ti_of_match[] = {

	{ .compatible = "ti,j721e-usb", },

	{ .compatible = "ti,am64-usb", },
@@ -243,6 +267,7 @@ static struct platform_driver cdns_ti_driver = { 
	.driver		= {

		.name	= "cdns3-ti",

		.of_match_table	= cdns_ti_of_match,

		.pm     = pm_ptr(&cdns_ti_pm_ops),

	},

};