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: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
This commit is contained in:
Boris Brezillon 2015-01-06 14:46:58 +01:00 committed by Felipe Balbi
parent 6f15e2dc71
commit 3280e67536
3 changed files with 52 additions and 36 deletions

View file

@ -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.

View file

@ -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)
static void 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));
if (udc->errata && udc->errata->toggle_bias)
udc->errata->toggle_bias(udc, is_on);
}
#else
static void toggle_bias(int 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 = {

View file

@ -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;