USB: qcaux: Add Motorola modem UARTs

[Tony Lindgren <tony@atomide.com>]

* Tony Lindgren <tony@atomide.com> [181206 07:48]:
> * Johan Hovold <johan@kernel.org> [181206 06:00]:
> > How do switch modes by the way?
> 
> The flash mode gets enabled with the control GPIOs. I just
> did a quick test patch for phy-mapphone-mdm6600 using module
> param for that. Then additionally the modem USB can be
> multiplexed to the PC by configuring mode in phy-cpcap-usb
> but I don't have a patch for that.

FYI, below is the test patch against next I used for switching
between normal mode and flash mode with a module param flash_mode
if somebody wants to play with it. For flashing the modem,
Android update-binary does it to deal with the signed modem
firmware, I don't know of the details what happens there.

Kishon, is there maybe some phy framework sysfs property
we could use for switching phy modes?

Regards,

Tony

8< -----------------------

diff --git a/drivers/phy/motorola/phy-mapphone-mdm6600.c b/drivers/phy/motorola/phy-mapphone-mdm6600.c
--- a/drivers/phy/motorola/phy-mapphone-mdm6600.c
+++ b/drivers/phy/motorola/phy-mapphone-mdm6600.c
@@ -80,6 +80,10 @@ enum phy_mdm6600_status {
 	PHY_MDM6600_STATUS_UNDEFINED,
 };
 
+static bool flash_mode;
+module_param(flash_mode, bool, 0);
+MODULE_PARM_DESC(flash_mode, "Start mdm6600 in flash mode");
+
 static const char * const
 phy_mdm6600_status_name[] = {
 	"off", "busy", "qc_dl", "ram_dl", "awake",
@@ -249,6 +253,9 @@ static irqreturn_t phy_mdm6600_wakeirq_thread(int irq, void *data)
 	struct phy_mdm6600 *ddata = data;
 	struct gpio_desc *mode_gpio1;
 
+	if (flash_mode)
+		return IRQ_NONE;
+
 	mode_gpio1 = ddata->mode_gpios->desc[PHY_MDM6600_MODE1];
 	dev_dbg(ddata->dev, "OOB wake on mode_gpio1: %i\n",
 		gpiod_get_value(mode_gpio1));
@@ -377,8 +384,13 @@ static int phy_mdm6600_device_power_on(struct phy_mdm6600 *ddata)
 	 * to configure USB flashing mode later on based on a module
 	 * parameter.
 	 */
-	gpiod_set_value_cansleep(mode_gpio0, 0);
-	gpiod_set_value_cansleep(mode_gpio1, 0);
+	if (flash_mode) {
+		gpiod_set_value_cansleep(mode_gpio0, 1);
+		gpiod_set_value_cansleep(mode_gpio1, 1);
+	} else {
+		gpiod_set_value_cansleep(mode_gpio0, 0);
+		gpiod_set_value_cansleep(mode_gpio1, 0);
+	}
 
 	/* Request start-up mode */
 	phy_mdm6600_cmd(ddata, PHY_MDM6600_CMD_NO_BYPASS);
@@ -414,7 +426,12 @@ static int phy_mdm6600_device_power_on(struct phy_mdm6600 *ddata)
 		dev_err(ddata->dev, "Timed out powering up\n");
 	}
 
-	/* Reconfigure mode1 GPIO as input for OOB wake */
+	/* Maybe reconfigure mode1 GPIO as input for OOB wake? */
+	if (flash_mode) {
+		dev_info(ddata->dev, "Started in flash mode\n");
+		goto done;
+	}
+
 	gpiod_direction_input(mode_gpio1);
 
 	wakeirq = gpiod_to_irq(mode_gpio1);
@@ -431,7 +448,7 @@ static int phy_mdm6600_device_power_on(struct phy_mdm6600 *ddata)
 	if (error)
 		dev_warn(ddata->dev, "no modem wakeirq irq%i: %i\n",
 			 wakeirq, error);
-
+done:
 	ddata->running = true;
 
 	return error;
@@ -499,6 +516,9 @@ static void phy_mdm6600_modem_wake(struct work_struct *work)
 {
 	struct phy_mdm6600 *ddata;
 
+	if (flash_mode)
+		return;
+
 	ddata = container_of(work, struct phy_mdm6600, modem_wake_work.work);
 	phy_mdm6600_wake_modem(ddata);
 	schedule_delayed_work(&ddata->modem_wake_work,
@@ -509,6 +529,9 @@ static int __maybe_unused phy_mdm6600_runtime_suspend(struct device *dev)
 {
 	struct phy_mdm6600 *ddata = dev_get_drvdata(dev);
 
+	if (flash_mode)
+		return 0;
+
 	cancel_delayed_work_sync(&ddata->modem_wake_work);
 	ddata->awake = false;
 
@@ -519,6 +542,9 @@ static int __maybe_unused phy_mdm6600_runtime_resume(struct device *dev)
 {
 	struct phy_mdm6600 *ddata = dev_get_drvdata(dev);
 
+	if (flash_mode)
+		return 0;
+
 	phy_mdm6600_modem_wake(&ddata->modem_wake_work.work);
 	ddata->awake = true;