From: Robert Jarzmik <robert.jarzmik@xxxxxxx>
Prepare pxa27x_udc to handle usb D+ pullup properly : it
should connect the pullup resistor and disconnect it only
if no external transceiver is handling it.
[ dbrownell@xxxxxxxxxxxxxxxxxxxxx: kerneldoc and gpio fixes ]
Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/usb/gadget/pxa27x_udc.c | 140 +++++++++++++++++++++++++++++++++++---
drivers/usb/gadget/pxa27x_udc.h | 6 +
2 files changed, 138 insertions(+), 8 deletions(-)
--- a/drivers/usb/gadget/pxa27x_udc.c
+++ b/drivers/usb/gadget/pxa27x_udc.c
@@ -30,6 +30,7 @@
#include <linux/proc_fs.h>
#include <linux/clk.h>
#include <linux/irq.h>
+#include <linux/gpio.h>
#include <asm/byteorder.h>
#include <mach/hardware.h>
@@ -1471,6 +1472,32 @@ static struct usb_ep_ops pxa_ep_ops = {
.fifo_flush = pxa_ep_fifo_flush,
};
+/**
+ * dplus_pullup - Connect or disconnect pullup resistor to D+ pin
+ * @udc: udc device
+ * @on: 0 if disconnect pullup resistor, 1 otherwise
+ * Context: any
+ *
+ * Handle D+ pullup resistor, make the device visible to the usb bus, and
+ * declare it as a full speed usb device
+ */
+static void dplus_pullup(struct pxa_udc *udc, int on)
+{
+ if (on) {
+ if (gpio_is_valid(udc->mach->gpio_pullup))
+ gpio_set_value(udc->mach->gpio_pullup,
+ !udc->mach->gpio_pullup_inverted);
+ if (udc->mach->udc_command)
+ udc->mach->udc_command(PXA2XX_UDC_CMD_CONNECT);
+ } else {
+ if (gpio_is_valid(udc->mach->gpio_pullup))
+ gpio_set_value(udc->mach->gpio_pullup,
+ udc->mach->gpio_pullup_inverted);
+ if (udc->mach->udc_command)
+ udc->mach->udc_command(PXA2XX_UDC_CMD_DISCONNECT);
+ }
+ udc->pullup_on = on;
+}
/**
* pxa_udc_get_frame - Returns usb frame number
@@ -1500,21 +1527,91 @@ static int pxa_udc_wakeup(struct usb_gad
return 0;
}
+static void udc_enable(struct pxa_udc *udc);
+static void udc_disable(struct pxa_udc *udc);
+
+/**
+ * should_enable_udc - Tells if UDC should be enabled
+ * @udc: udc device
+ * Context: any
+ *
+ * The UDC should be enabled if :
+ * - the pullup resistor is connected
+ * - and a gadget driver is bound
+ *
+ * Returns 1 if UDC should be enabled, 0 otherwise
+ */
+static int should_enable_udc(struct pxa_udc *udc)
+{
+ int put_on;
+
+ put_on = ((udc->pullup_on) && (udc->driver));
+ return put_on;
+}
+
+/**
+ * should_disable_udc - Tells if UDC should be disabled
+ * @udc: udc device
+ * Context: any
+ *
+ * The UDC should be disabled if :
+ * - the pullup resistor is not connected
+ * - or no gadget driver is bound
+ *
+ * Returns 1 if UDC should be disabled
+ */
+static int should_disable_udc(struct pxa_udc *udc)
+{
+ int put_off;
+
+ put_off = ((!udc->pullup_on) || (!udc->driver));
+ return put_off;
+}
+
+/**
+ * pxa_udc_pullup - Offer manual D+ pullup control
+ * @_gadget: usb gadget using the control
+ * @is_active: 0 if disconnect, else connect D+ pullup resistor
+ * Context: !in_interrupt()
+ *
+ * Returns 0 if OK, -EOPNOTSUPP if udc driver doesn't handle D+ pullup
+ */
+static int pxa_udc_pullup(struct usb_gadget *_gadget, int is_active)
+{
+ struct pxa_udc *udc = to_gadget_udc(_gadget);
+
+ if (!gpio_is_valid(udc->mach->gpio_pullup) && !udc->mach->udc_command)
+ return -EOPNOTSUPP;
+
+ dplus_pullup(udc, is_active);
+
+ if (should_enable_udc(udc))
+ udc_enable(udc);
+ if (should_disable_udc(udc))
+ udc_disable(udc);
+ return 0;
+}
+
static const struct usb_gadget_ops pxa_udc_ops = {
.get_frame = pxa_udc_get_frame,
.wakeup = pxa_udc_wakeup,
+ .pullup = pxa_udc_pullup,
/* current versions must always be self-powered */
};
/**
* udc_disable - disable udc device controller
* @udc: udc device
+ * Context: any
*
* Disables the udc device : disables clocks, udc interrupts, control endpoint
* interrupts.
*/
static void udc_disable(struct pxa_udc *udc)
{
+ if (!udc->enabled)
+ return;
+
udc_writel(udc, UDCICR0, 0);
udc_writel(udc, UDCICR1, 0);
@@ -1523,8 +1620,8 @@ static void udc_disable(struct pxa_udc *
ep0_idle(udc);
udc->gadget.speed = USB_SPEED_UNKNOWN;
- if (udc->mach->udc_command)
- udc->mach->udc_command(PXA2XX_UDC_CMD_DISCONNECT);
+
+ udc->enabled = 0;
}
/**
@@ -1570,6 +1667,9 @@ static __init void udc_init_data(struct
*/
static void udc_enable(struct pxa_udc *udc)
{
+ if (udc->enabled)
+ return;
+
udc_writel(udc, UDCICR0, 0);
udc_writel(udc, UDCICR1, 0);
udc_clear_mask_UDCCR(udc, UDCCR_UDE);
@@ -1598,9 +1698,7 @@ static void udc_enable(struct pxa_udc *u
/* enable ep0 irqs */
pio_irq_enable(&udc->pxa_ep[0]);
- dev_info(udc->dev, "UDC connecting\n");
- if (udc->mach->udc_command)
- udc->mach->udc_command(PXA2XX_UDC_CMD_CONNECT);
+ udc->enabled = 1;
}
/**
@@ -1612,6 +1710,9 @@ static void udc_enable(struct pxa_udc *u
* usb traffic follows until a disconnect is reported. Then a host may connect
* again, or the driver might get unbound.
*
+ * Note that the udc is not automatically enabled. Check function
+ * should_enable_udc().
+ *
* Returns 0 if no error, -EINVAL, -ENODEV, -EBUSY otherwise
*/
int usb_gadget_register_driver(struct usb_gadget_driver *driver)
@@ -1630,6 +1731,7 @@ int usb_gadget_register_driver(struct us
/* first hook up the driver ... */
udc->driver = driver;
udc->gadget.dev.driver = &driver->driver;
+ dplus_pullup(udc, 1);
retval = device_add(&udc->gadget.dev);
if (retval) {
@@ -1645,7 +1747,8 @@ int usb_gadget_register_driver(struct us
dev_dbg(udc->dev, "registered gadget driver '%s'\n",
driver->driver.name);
- udc_enable(udc);
+ if (should_enable_udc(udc))
+ udc_enable(udc);
return 0;
bind_fail:
@@ -1699,6 +1802,7 @@ int usb_gadget_unregister_driver(struct
stop_activity(udc, driver);
udc_disable(udc);
+ dplus_pullup(udc, 0);
driver->unbind(&udc->gadget);
udc->driver = NULL;
@@ -2212,7 +2316,7 @@ static int __init pxa_udc_probe(struct p
{
struct resource *regs;
struct pxa_udc *udc = &memory;
- int retval;
+ int retval = 0, gpio;
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs)
@@ -2224,6 +2328,19 @@ static int __init pxa_udc_probe(struct p
udc->dev = &pdev->dev;
udc->mach = pdev->dev.platform_data;
+ gpio = udc->mach->gpio_pullup;
+ if (gpio_is_valid(gpio)) {
+ retval = gpio_request(gpio, "USB D+ pullup");
+ if (retval == 0)
+ gpio_direction_output(gpio,
+ udc->mach->gpio_pullup_inverted);
+ }
+ if (retval) {
+ dev_err(&pdev->dev, "Couldn't request gpio %d : %d\n",
+ gpio, retval);
+ return retval;
+ }
+
udc->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(udc->clk)) {
retval = PTR_ERR(udc->clk);
@@ -2273,10 +2390,13 @@ err_clk:
static int __exit pxa_udc_remove(struct platform_device *_dev)
{
struct pxa_udc *udc = platform_get_drvdata(_dev);
+ int gpio = udc->mach->gpio_pullup;
usb_gadget_unregister_driver(udc->driver);
free_irq(udc->irq, udc);
pxa_cleanup_debugfs(udc);
+ if (gpio_is_valid(gpio))
+ gpio_free(gpio);
platform_set_drvdata(_dev, NULL);
the_controller = NULL;
@@ -2319,6 +2439,8 @@ static int pxa_udc_suspend(struct platfo
}
udc_disable(udc);
+ udc->pullup_resume = udc->pullup_on;
+ dplus_pullup(udc, 0);
return 0;
}
@@ -2346,7 +2468,9 @@ static int pxa_udc_resume(struct platfor
ep->udccsr_value, ep->udccr_value);
}
- udc_enable(udc);
+ dplus_pullup(udc, udc->pullup_resume);
+ if (should_enable_udc(udc))
+ udc_enable(udc);
/*
* We do not handle OTG yet.
*
--- a/drivers/usb/gadget/pxa27x_udc.h
+++ b/drivers/usb/gadget/pxa27x_udc.h
@@ -425,6 +425,9 @@ struct udc_stats {
* @stats: statistics on udc usage
* @udc_usb_ep: array of usb endpoints offered by the gadget
* @pxa_ep: array of pxa available endpoints
+ * @enabled: UDC was enabled by a previous udc_enable()
+ * @pullup_on: if pullup resistor connected to D+ pin
+ * @pullup_resume: if pullup resistor should be connected to D+ pin on resume
* @config: UDC active configuration
* @last_interface: UDC interface of the last SET_INTERFACE host request
* @last_alternate: UDC altsetting of the last SET_INTERFACE host request
@@ -450,6 +453,9 @@ struct pxa_udc {
struct udc_usb_ep udc_usb_ep[NR_USB_ENDPOINTS];
struct pxa_ep pxa_ep[NR_PXA_ENDPOINTS];
+ unsigned enabled:1;
+ unsigned pullup_on:1;
+ unsigned pullup_resume:1;
unsigned config:2;
unsigned last_interface:3;
unsigned last_alternate:3;
--
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