avr32: Enable pullup on USART TX lines

Make USART initialization conform to Section 24.6.1 in the AT32AP7000 manual,
i.e. "To prevent the TXD line from falling when the USART is disabled, the use
of an internal pull up is mandatory."

Signed-off-by: Anders Blomdell <anders.blomdell@control.lth.se>
[haavard.skinnemoen@atmel.com: enable pullup on RX as well]
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
This commit is contained in:
Anders Blomdell 2008-10-24 14:54:08 +02:00 committed by Haavard Skinnemoen
parent 57f8f7b60d
commit 105462632c

View File

@ -967,28 +967,28 @@ static inline void configure_usart0_pins(void)
{
u32 pin_mask = (1 << 8) | (1 << 9); /* RXD & TXD */
select_peripheral(PIOA, pin_mask, PERIPH_B, 0);
select_peripheral(PIOA, pin_mask, PERIPH_B, AT32_GPIOF_PULLUP);
}
static inline void configure_usart1_pins(void)
{
u32 pin_mask = (1 << 17) | (1 << 18); /* RXD & TXD */
select_peripheral(PIOA, pin_mask, PERIPH_A, 0);
select_peripheral(PIOA, pin_mask, PERIPH_A, AT32_GPIOF_PULLUP);
}
static inline void configure_usart2_pins(void)
{
u32 pin_mask = (1 << 26) | (1 << 27); /* RXD & TXD */
select_peripheral(PIOB, pin_mask, PERIPH_B, 0);
select_peripheral(PIOB, pin_mask, PERIPH_B, AT32_GPIOF_PULLUP);
}
static inline void configure_usart3_pins(void)
{
u32 pin_mask = (1 << 18) | (1 << 17); /* RXD & TXD */
select_peripheral(PIOB, pin_mask, PERIPH_B, 0);
select_peripheral(PIOB, pin_mask, PERIPH_B, AT32_GPIOF_PULLUP);
}
static struct platform_device *__initdata at32_usarts[4];