Commit 9492535e authored by Tony Lindgren's avatar Tony Lindgren Committed by Kishon Vijay Abraham I
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phy: cpcap-usb: Improve host vs docked mode detection 



When docked to a Motorola lapdock or media dock, we're in USB A-host mode
with VBUS provided by the dock. When in regular USB A-host mode, we're
providing the VBUS. And in regular USB A-host mode we must also keep
kicking the VBUS to keep it active.

Let's wait a bit before configuring the USB PHY to allow some time between
the ID and VBUS changes. And let's add vbus_provider flag so we can detect
docked mode and regularo USB A-host mode better.

With better USB A-host mode detection, we can now also just kick the
VBUS to keep it enabled and leave out the unnecessary line muxing.

We only need to set and clear vbus_provider in the delayed work so no
locking is needed for it currently.

Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Sebastian Reichel <sre@kernel.org>
Acked-by: default avatarPavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarKishon Vijay Abraham I <kishon@ti.com>
parent 63078b6b

drivers/phy/motorola/phy-cpcap-usb.c

+58 −15
Original line number Diff line number Diff line
@@ -134,6 +134,8 @@ struct cpcap_phy_ddata { 
	struct iio_channel *id;

	struct regulator *vusb;

	atomic_t active;

	unsigned int vbus_provider:1;

	unsigned int docked:1;

};



static bool cpcap_usb_vbus_valid(struct cpcap_phy_ddata *ddata)
@@ -233,11 +235,11 @@ static void cpcap_usb_detect(struct work_struct *work) 
	if (error)

		return;



	if (s.id_ground) {

		dev_dbg(ddata->dev, "id ground, USB host mode\n");

		error = cpcap_usb_set_usb_mode(ddata);

		if (error)

			goto out_err;

	vbus = cpcap_usb_vbus_valid(ddata);



	/* We need to kick the VBUS as USB A-host */

	if (s.id_ground && ddata->vbus_provider) {

		dev_dbg(ddata->dev, "still in USB A-host mode, kicking VBUS\n");



		cpcap_usb_try_musb_mailbox(ddata, MUSB_ID_GROUND);
@@ -251,29 +253,68 @@ static void cpcap_usb_detect(struct work_struct *work) 
		return;

	}



	error = regmap_update_bits(ddata->reg, CPCAP_REG_USBC3,

				   CPCAP_BIT_VBUSSTBY_EN |

				   CPCAP_BIT_VBUSEN_SPI, 0);

	if (vbus && s.id_ground && ddata->docked) {

		dev_dbg(ddata->dev, "still docked as A-host, signal ID down\n");



		cpcap_usb_try_musb_mailbox(ddata, MUSB_ID_GROUND);



		return;

	}



	/* No VBUS needed with docks */

	if (vbus && s.id_ground && !ddata->vbus_provider) {

		dev_dbg(ddata->dev, "connected to a dock\n");



		ddata->docked = true;



		error = cpcap_usb_set_usb_mode(ddata);

		if (error)

			goto out_err;



	vbus = cpcap_usb_vbus_valid(ddata);

		cpcap_usb_try_musb_mailbox(ddata, MUSB_ID_GROUND);



	if (vbus) {

		/* Are we connected to a docking station with vbus? */

		if (s.id_ground) {

			dev_dbg(ddata->dev, "connected to a dock\n");

		/*

		 * Force check state again after musb has reoriented,

		 * otherwise devices won't enumerate after loading PHY

		 * driver.

		 */

		schedule_delayed_work(&ddata->detect_work,

				      msecs_to_jiffies(1000));



		return;

	}



	if (s.id_ground && !ddata->docked) {

		dev_dbg(ddata->dev, "id ground, USB host mode\n");



		ddata->vbus_provider = true;



			/* No VBUS needed with docks */

		error = cpcap_usb_set_usb_mode(ddata);

		if (error)

			goto out_err;



		cpcap_usb_try_musb_mailbox(ddata, MUSB_ID_GROUND);



		error = regmap_update_bits(ddata->reg, CPCAP_REG_USBC3,

					   CPCAP_BIT_VBUSSTBY_EN |

					   CPCAP_BIT_VBUSEN_SPI,

					   CPCAP_BIT_VBUSEN_SPI);

		if (error)

			goto out_err;



		return;

	}



	error = regmap_update_bits(ddata->reg, CPCAP_REG_USBC3,

				   CPCAP_BIT_VBUSSTBY_EN |

				   CPCAP_BIT_VBUSEN_SPI, 0);

	if (error)

		goto out_err;



	vbus = cpcap_usb_vbus_valid(ddata);



	/* Otherwise assume we're connected to a USB host */

	if (vbus) {

		dev_dbg(ddata->dev, "connected to USB host\n");

		error = cpcap_usb_set_usb_mode(ddata);

		if (error)
@@ -283,6 +324,8 @@ static void cpcap_usb_detect(struct work_struct *work) 
		return;

	}



	ddata->vbus_provider = false;

	ddata->docked = false;

	cpcap_usb_try_musb_mailbox(ddata, MUSB_VBUS_OFF);



	/* Default to debug UART mode */