[PATCH 3/8] Bluetooth: btnxpuart: Add M.2 Bluetooth device support using pwrseq

Sherry Sun sherry.sun at nxp.com
Sun Jun 21 20:51:54 PDT 2026


> On Thu, Jun 18, 2026 at 06:10:42PM +0800, Sherry Sun (OSS) wrote:
> > From: Sherry Sun <sherry.sun at nxp.com>
> >
> > Power supply to the M.2 Bluetooth device attached to the host using
> > M.2 connector is controlled using the 'uart' pwrseq device. So add
> > support for getting the pwrseq device if the OF graph link is present.
> > Once obtained, the existing pwrseq APIs can be used to control the
> > power supplies of the
> > M.2 card.
> >
> > Signed-off-by: Sherry Sun <sherry.sun at nxp.com>
> > ---
> >  drivers/bluetooth/btnxpuart.c | 33 ++++++++++++++++++++++++++++++---
> >  1 file changed, 30 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/bluetooth/btnxpuart.c
> > b/drivers/bluetooth/btnxpuart.c index e7036a48ce48..1aa8972f0dab
> > 100644
> > --- a/drivers/bluetooth/btnxpuart.c
> > +++ b/drivers/bluetooth/btnxpuart.c
> > @@ -9,6 +9,8 @@
> >
> >  #include <linux/serdev.h>
> >  #include <linux/of.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/pwrseq/consumer.h>
> >  #include <linux/skbuff.h>
> >  #include <linux/unaligned.h>
> >  #include <linux/firmware.h>
> > @@ -211,6 +213,7 @@ struct btnxpuart_dev {
> >
> >  	struct ps_data psdata;
> >  	struct btnxpuart_data *nxp_data;
> > +	struct pwrseq_desc *pwrseq;
> >  	struct reset_control *pdn;
> >  	struct hci_uart hu;
> >  };
> > @@ -1866,11 +1869,27 @@ static int nxp_serdev_probe(struct
> serdev_device *serdev)
> >  		return err;
> >  	}
> >
> > +	if (of_graph_is_present(dev_of_node(&serdev->ctrl->dev))) {
> > +		struct pwrseq_desc *pwrseq;
> > +
> > +		pwrseq = devm_pwrseq_get(&serdev->ctrl->dev, "uart");
> > +		if (IS_ERR(pwrseq))
> > +			return PTR_ERR(pwrseq);
> > +
> > +		nxpdev->pwrseq = pwrseq;
> > +		err = pwrseq_power_on(pwrseq);
> > +		if (err) {
> > +			dev_err(&serdev->dev, "Failed to power on
> pwrseq\n");
> > +			return err;
> > +		}
> 
> Can you provide helper function like devm clk get and enabled?
> like devm_pwrsq_get_on()
> 
> So simple below error handle.

Ok, will try.

Best Regards
Sherry

> 
> > +	}
> > +
> >  	/* Initialize and register HCI device */
> >  	hdev = hci_alloc_dev();
> >  	if (!hdev) {
> >  		dev_err(&serdev->dev, "Can't allocate HCI device\n");
> > -		return -ENOMEM;
> > +		err = -ENOMEM;
> > +		goto err_pwrseq_power_off;
> >  	}
> >
> >  	reset_control_deassert(nxpdev->pdn);
> > @@ -1903,11 +1922,14 @@ static int nxp_serdev_probe(struct
> > serdev_device *serdev)
> >
> >  	if (hci_register_dev(hdev) < 0) {
> >  		dev_err(&serdev->dev, "Can't register HCI device\n");
> > +		err = -ENODEV;
> >  		goto probe_fail;
> >  	}
> >
> > -	if (ps_setup(hdev))
> > +	if (ps_setup(hdev)) {
> > +		err = -ENODEV;
> >  		goto probe_fail;
> > +	}
> >
> >  	hci_devcd_register(hdev, nxp_coredump, nxp_coredump_hdr,
> >  			   nxp_coredump_notify);
> > @@ -1917,7 +1939,10 @@ static int nxp_serdev_probe(struct
> > serdev_device *serdev)
> >  probe_fail:
> >  	reset_control_assert(nxpdev->pdn);
> >  	hci_free_dev(hdev);
> > -	return -ENODEV;
> > +err_pwrseq_power_off:
> > +	if (nxpdev->pwrseq)
> > +		pwrseq_power_off(nxpdev->pwrseq);
> > +	return err;
> >  }
> >
> >  static void nxp_serdev_remove(struct serdev_device *serdev) @@
> > -1944,6 +1969,8 @@ static void nxp_serdev_remove(struct serdev_device
> *serdev)
> >  	ps_cleanup(nxpdev);
> >  	hci_unregister_dev(hdev);
> >  	reset_control_assert(nxpdev->pdn);
> > +	if (nxpdev->pwrseq)
> > +		pwrseq_power_off(nxpdev->pwrseq);
> >  	hci_free_dev(hdev);
> >  }
> >
> > --
> > 2.50.1
> >
> >



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