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Commit 3280e675 authored by Boris Brezillon's avatar Boris Brezillon Committed by Felipe Balbi
Browse files

usb: atmel_usba_udc: Rework at91sam9rl errata handling 



at91sam9rl SoC has an erratum forcing us to toggle the BIAS on USB
suspend/resume events.

This specific handling is only activated when CONFIG_ARCH_AT91SAM9RL is
set and this option is only set when building a non-DT kernel, which is
problematic since non-DT support for at91sam9rl SoC has been removed.

Rework the toggle_bias implementation to attach it to the "at91sam9rl-udc"
compatible string.

Add new compatible strings to avoid executing at91sam9rl erratum handling
on other SoCs.

Acked-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent 6f15e2dc

Documentation/devicetree/bindings/usb/atmel-usb.txt

+4 −1
Original line number Diff line number Diff line
@@ -51,7 +51,10 @@ usb1: gadget@fffa4000 { 
Atmel High-Speed USB device controller



Required properties:

 - compatible: Should be "atmel,at91sam9rl-udc"

 - compatible: Should be one of the following

	       "at91sam9rl-udc"

	       "at91sam9g45-udc"

	       "sama5d3-udc"

 - reg: Address and length of the register set for the device

 - interrupts: Should contain usba interrupt

 - ep childnode: To specify the number of endpoints and their properties.

drivers/usb/gadget/udc/atmel_usba_udc.c

+43 −35
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
 * published by the Free Software Foundation.

 */

#include <linux/clk.h>

#include <linux/clk/at91_pmc.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/interrupt.h>
@@ -324,28 +325,12 @@ static int vbus_is_present(struct usba_udc *udc) 
	return 1;

}



#if defined(CONFIG_ARCH_AT91SAM9RL)



#include <linux/clk/at91_pmc.h>



static void toggle_bias(int is_on)

{

	unsigned int uckr = at91_pmc_read(AT91_CKGR_UCKR);



	if (is_on)

		at91_pmc_write(AT91_CKGR_UCKR, uckr | AT91_PMC_BIASEN);

	else

		at91_pmc_write(AT91_CKGR_UCKR, uckr & ~(AT91_PMC_BIASEN));

}



#else



static void toggle_bias(int is_on)

static void toggle_bias(struct usba_udc *udc, int is_on)

{

	if (udc->errata && udc->errata->toggle_bias)

		udc->errata->toggle_bias(udc, is_on);

}



#endif /* CONFIG_ARCH_AT91SAM9RL */



static void next_fifo_transaction(struct usba_ep *ep, struct usba_request *req)

{

	unsigned int transaction_len;
@@ -1620,7 +1605,7 @@ static irqreturn_t usba_udc_irq(int irq, void *devid) 
	DBG(DBG_INT, "irq, status=%#08x\n", status);



	if (status & USBA_DET_SUSPEND) {

		toggle_bias(0);

		toggle_bias(udc, 0);

		usba_writel(udc, INT_CLR, USBA_DET_SUSPEND);

		DBG(DBG_BUS, "Suspend detected\n");

		if (udc->gadget.speed != USB_SPEED_UNKNOWN
@@ -1632,7 +1617,7 @@ static irqreturn_t usba_udc_irq(int irq, void *devid) 
	}



	if (status & USBA_WAKE_UP) {

		toggle_bias(1);

		toggle_bias(udc, 1);

		usba_writel(udc, INT_CLR, USBA_WAKE_UP);

		DBG(DBG_BUS, "Wake Up CPU detected\n");

	}
@@ -1736,13 +1721,13 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid) 
	vbus = vbus_is_present(udc);

	if (vbus != udc->vbus_prev) {

		if (vbus) {

			toggle_bias(1);

			toggle_bias(udc, 1);

			usba_writel(udc, CTRL, USBA_ENABLE_MASK);

			usba_writel(udc, INT_ENB, USBA_END_OF_RESET);

		} else {

			udc->gadget.speed = USB_SPEED_UNKNOWN;

			reset_all_endpoints(udc);

			toggle_bias(0);

			toggle_bias(udc, 0);

			usba_writel(udc, CTRL, USBA_DISABLE_MASK);

			if (udc->driver->disconnect) {

				spin_unlock(&udc->lock);
@@ -1788,7 +1773,7 @@ static int atmel_usba_start(struct usb_gadget *gadget, 
	/* If Vbus is present, enable the controller and wait for reset */

	spin_lock_irqsave(&udc->lock, flags);

	if (vbus_is_present(udc) && udc->vbus_prev == 0) {

		toggle_bias(1);

		toggle_bias(udc, 1);

		usba_writel(udc, CTRL, USBA_ENABLE_MASK);

		usba_writel(udc, INT_ENB, USBA_END_OF_RESET);

	}
@@ -1811,7 +1796,7 @@ static int atmel_usba_stop(struct usb_gadget *gadget) 
	spin_unlock_irqrestore(&udc->lock, flags);



	/* This will also disable the DP pullup */

	toggle_bias(0);

	toggle_bias(udc, 0);

	usba_writel(udc, CTRL, USBA_DISABLE_MASK);



	clk_disable_unprepare(udc->hclk);
@@ -1823,6 +1808,29 @@ static int atmel_usba_stop(struct usb_gadget *gadget) 
}



#ifdef CONFIG_OF

static void at91sam9rl_toggle_bias(struct usba_udc *udc, int is_on)

{

	unsigned int uckr = at91_pmc_read(AT91_CKGR_UCKR);



	if (is_on)

		at91_pmc_write(AT91_CKGR_UCKR, uckr | AT91_PMC_BIASEN);

	else

		at91_pmc_write(AT91_CKGR_UCKR, uckr & ~(AT91_PMC_BIASEN));

}



static const struct usba_udc_errata at91sam9rl_errata = {

	.toggle_bias = at91sam9rl_toggle_bias,

};



static const struct of_device_id atmel_udc_dt_ids[] = {

	{ .compatible = "atmel,at91sam9rl-udc", .data = &at91sam9rl_errata },

	{ .compatible = "atmel,at91sam9g45-udc" },

	{ .compatible = "atmel,sama5d3-udc" },

	{ /* sentinel */ }

};



MODULE_DEVICE_TABLE(of, atmel_udc_dt_ids);



static struct usba_ep * atmel_udc_of_init(struct platform_device *pdev,

						    struct usba_udc *udc)

{
@@ -1830,10 +1838,17 @@ static struct usba_ep * atmel_udc_of_init(struct platform_device *pdev, 
	const char *name;

	enum of_gpio_flags flags;

	struct device_node *np = pdev->dev.of_node;

	const struct of_device_id *match;

	struct device_node *pp;

	int i, ret;

	struct usba_ep *eps, *ep;



	match = of_match_node(atmel_udc_dt_ids, np);

	if (!match)

		return ERR_PTR(-EINVAL);



	udc->errata = match->data;



	udc->num_ep = 0;



	udc->vbus_pin = of_get_named_gpio_flags(np, "atmel,vbus-gpio", 0,
@@ -2024,7 +2039,7 @@ static int usba_udc_probe(struct platform_device *pdev) 
		dev_err(&pdev->dev, "Unable to enable pclk, aborting.\n");

		return ret;

	}

	toggle_bias(0);



	usba_writel(udc, CTRL, USBA_DISABLE_MASK);

	clk_disable_unprepare(pclk);
@@ -2033,6 +2048,8 @@ static int usba_udc_probe(struct platform_device *pdev) 
	else

		udc->usba_ep = usba_udc_pdata(pdev, udc);



	toggle_bias(udc, 0);



	if (IS_ERR(udc->usba_ep))

		return PTR_ERR(udc->usba_ep);
@@ -2092,15 +2109,6 @@ static int __exit usba_udc_remove(struct platform_device *pdev) 
	return 0;

}



#if defined(CONFIG_OF)

static const struct of_device_id atmel_udc_dt_ids[] = {

	{ .compatible = "atmel,at91sam9rl-udc" },

	{ /* sentinel */ }

};



MODULE_DEVICE_TABLE(of, atmel_udc_dt_ids);

#endif



static struct platform_driver udc_driver = {

	.remove		= __exit_p(usba_udc_remove),

	.driver		= {

drivers/usb/gadget/udc/atmel_usba_udc.h

+5 −0
Original line number Diff line number Diff line
@@ -304,6 +304,10 @@ struct usba_request { 
	unsigned int				mapped:1;

};



struct usba_udc_errata {

	void (*toggle_bias)(struct usba_udc *udc, int is_on);

};



struct usba_udc {

	/* Protect hw registers from concurrent modifications */

	spinlock_t lock;
@@ -314,6 +318,7 @@ struct usba_udc { 
	struct usb_gadget gadget;

	struct usb_gadget_driver *driver;

	struct platform_device *pdev;

	const struct usba_udc_errata *errata;

	int irq;

	int vbus_pin;

	int vbus_pin_inverted;