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authorTomoya MORINAGA <tomoya.rohm@gmail.com>2012-02-03 16:14:18 +0900
committerFelipe Balbi <balbi@ti.com>2012-02-09 09:58:48 +0200
commit637b78eb31e0b167ed913f1750bb645dfeda38f0 (patch)
tree9496e1f2489bedef09c523bd0f0f0f960e553014
parentdd63180b758d5972fc90621af0741d5bfae1a684 (diff)
usb: gadget: pch_udc: Detecting VBUS through GPIO with interrupt
Problem: pch_udc continues operation even if VBUS becomes Low. pch_udc performs D+ pulling up before VBUS becomes High. USB device should be controlled according to VBUS state. Root cause: The current pch_udc is not always monitoring VBUS. Solution: The change of VBUS is detected using an interrupt of GPIO. If VBUS became Low, pch_udc handles 'disconnect'. After VBUS became High, a pull improves D+, and pch_udc handles 'connect'. [ balbi@ti.com : make it actually compile ] Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
-rw-r--r--drivers/usb/gadget/pch_udc.c87
1 files changed, 83 insertions, 4 deletions
diff --git a/drivers/usb/gadget/pch_udc.c b/drivers/usb/gadget/pch_udc.c
index 9c5ae2c1014..a992084d389 100644
--- a/drivers/usb/gadget/pch_udc.c
+++ b/drivers/usb/gadget/pch_udc.c
@@ -306,11 +306,15 @@ struct pch_udc_ep {
* struct pch_vbus_gpio_data - Structure holding GPIO informaton
* for detecting VBUS
* @port: gpio port number
+ * @intr: gpio interrupt number
* @irq_work_fall Structure for WorkQueue
+ * @irq_work_rise Structure for WorkQueue
*/
struct pch_vbus_gpio_data {
int port;
+ int intr;
struct work_struct irq_work_fall;
+ struct work_struct irq_work_rise;
};
/**
@@ -1296,8 +1300,10 @@ static void pch_vbus_gpio_work_fall(struct work_struct *irq_work)
dev->driver->disconnect(
&dev->gadget);
}
- pch_udc_reconnect(dev);
- dev_dbg(&dev->pdev->dev, "VBUS fell");
+ if (dev->vbus_gpio.intr)
+ pch_udc_init(dev);
+ else
+ pch_udc_reconnect(dev);
return;
}
vbus_saved = vbus;
@@ -1306,6 +1312,57 @@ static void pch_vbus_gpio_work_fall(struct work_struct *irq_work)
}
/**
+ * pch_vbus_gpio_work_rise() - This API checks VBUS is High.
+ * If VBUS is High, connect is processed
+ * @irq_work: Structure for WorkQueue
+ *
+ */
+static void pch_vbus_gpio_work_rise(struct work_struct *irq_work)
+{
+ struct pch_vbus_gpio_data *vbus_gpio = container_of(irq_work,
+ struct pch_vbus_gpio_data, irq_work_rise);
+ struct pch_udc_dev *dev =
+ container_of(vbus_gpio, struct pch_udc_dev, vbus_gpio);
+ int vbus;
+
+ if (!dev->vbus_gpio.port)
+ return;
+
+ mdelay(PCH_VBUS_INTERVAL);
+ vbus = pch_vbus_gpio_get_value(dev);
+
+ if (vbus == 1) {
+ dev_dbg(&dev->pdev->dev, "VBUS rose");
+ pch_udc_reconnect(dev);
+ return;
+ }
+}
+
+/**
+ * pch_vbus_gpio_irq() - IRQ handler for GPIO intrerrupt for changing VBUS
+ * @irq: Interrupt request number
+ * @dev: Reference to the device structure
+ *
+ * Return codes:
+ * 0: Success
+ * -EINVAL: GPIO port is invalid or can't be initialized.
+ */
+static irqreturn_t pch_vbus_gpio_irq(int irq, void *data)
+{
+ struct pch_udc_dev *dev = (struct pch_udc_dev *)data;
+
+ if (!dev->vbus_gpio.port || !dev->vbus_gpio.intr)
+ return IRQ_NONE;
+
+ if (pch_vbus_gpio_get_value(dev))
+ schedule_work(&dev->vbus_gpio.irq_work_rise);
+ else
+ schedule_work(&dev->vbus_gpio.irq_work_fall);
+
+ return IRQ_HANDLED;
+}
+
+/**
* pch_vbus_gpio_init() - This API initializes GPIO port detecting VBUS.
* @dev: Reference to the driver structure
* @vbus_gpio Number of GPIO port to detect gpio
@@ -1317,8 +1374,10 @@ static void pch_vbus_gpio_work_fall(struct work_struct *irq_work)
static int pch_vbus_gpio_init(struct pch_udc_dev *dev, int vbus_gpio_port)
{
int err;
+ int irq_num = 0;
dev->vbus_gpio.port = 0;
+ dev->vbus_gpio.intr = 0;
if (vbus_gpio_port <= -1)
return -EINVAL;
@@ -1341,6 +1400,21 @@ static int pch_vbus_gpio_init(struct pch_udc_dev *dev, int vbus_gpio_port)
gpio_direction_input(vbus_gpio_port);
INIT_WORK(&dev->vbus_gpio.irq_work_fall, pch_vbus_gpio_work_fall);
+ irq_num = gpio_to_irq(vbus_gpio_port);
+ if (irq_num > 0) {
+ irq_set_irq_type(irq_num, IRQ_TYPE_EDGE_BOTH);
+ err = request_irq(irq_num, pch_vbus_gpio_irq, 0,
+ "vbus_detect", dev);
+ if (!err) {
+ dev->vbus_gpio.intr = irq_num;
+ INIT_WORK(&dev->vbus_gpio.irq_work_rise,
+ pch_vbus_gpio_work_rise);
+ } else {
+ pr_err("%s: can't request irq %d, err: %d\n",
+ __func__, irq_num, err);
+ }
+ }
+
return 0;
}
@@ -1350,6 +1424,9 @@ static int pch_vbus_gpio_init(struct pch_udc_dev *dev, int vbus_gpio_port)
*/
static void pch_vbus_gpio_free(struct pch_udc_dev *dev)
{
+ if (dev->vbus_gpio.intr)
+ free_irq(dev->vbus_gpio.intr, dev);
+
if (dev->vbus_gpio.port)
gpio_free(dev->vbus_gpio.port);
}
@@ -2676,7 +2753,8 @@ static void pch_udc_dev_isr(struct pch_udc_dev *dev, u32 dev_intr)
}
pch_udc_reconnect(dev);
} else if ((dev->vbus_session == 0)
- && (vbus == 1))
+ && (vbus == 1)
+ && !dev->vbus_gpio.intr)
schedule_work(&dev->vbus_gpio.irq_work_fall);
dev_dbg(&dev->pdev->dev, "USB_SUSPEND\n");
@@ -2941,7 +3019,8 @@ static int pch_udc_start(struct usb_gadget_driver *driver,
pch_udc_setup_ep0(dev);
/* clear SD */
- pch_udc_clear_disconnect(dev);
+ if ((pch_vbus_gpio_get_value(dev) != 0) || !dev->vbus_gpio.intr)
+ pch_udc_clear_disconnect(dev);
dev->connected = 1;
return 0;