/*
- * linux/drivers/char/at91_serial.c
+ * linux/drivers/char/atmel_serial.c
*
- * Driver for Atmel AT91RM9200 Serial ports
+ * Driver for Atmel AT91 / AT32 Serial ports
* Copyright (C) 2003 Rick Bronson
*
* Based on drivers/char/serial_sa1100.c, by Deep Blue Solutions Ltd.
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
*
+ * DMA support added by Chip Coldwell.
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
#include <linux/sysrq.h>
#include <linux/tty_flip.h>
#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/atmel_pdc.h>
+#include <linux/atmel_serial.h>
#include <asm/io.h>
-#include <asm/arch/at91rm9200_pdc.h>
#include <asm/mach/serial_at91.h>
-#include <asm/arch/board.h>
-#include <asm/arch/system.h>
-#include <asm/arch/gpio.h>
+#include <mach/board.h>
+
+#ifdef CONFIG_ARM
+#include <mach/cpu.h>
+#include <mach/gpio.h>
+#endif
-#include "atmel_serial.h"
+#define PDC_BUFFER_SIZE 512
+/* Revisit: We should calculate this based on the actual port settings */
+#define PDC_RX_TIMEOUT (3 * 10) /* 3 bytes */
#if defined(CONFIG_SERIAL_ATMEL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
/* Use device name ttyAT, major 204 and minor 154-169. This is necessary if we
* should coexist with the 8250 driver, such as if we have an external 16C550
* UART. */
-#define SERIAL_AT91_MAJOR 204
+#define SERIAL_ATMEL_MAJOR 204
#define MINOR_START 154
-#define AT91_DEVICENAME "ttyAT"
+#define ATMEL_DEVICENAME "ttyAT"
#else
/* Use device name ttyS, major 4, minor 64-68. This is the usual serial port
* name, but it is legally reserved for the 8250 driver. */
-#define SERIAL_AT91_MAJOR TTY_MAJOR
+#define SERIAL_ATMEL_MAJOR TTY_MAJOR
#define MINOR_START 64
-#define AT91_DEVICENAME "ttyS"
+#define ATMEL_DEVICENAME "ttyS"
#endif
-#define AT91_ISR_PASS_LIMIT 256
-
-#define UART_PUT_CR(port,v) writel(v, (port)->membase + AT91_US_CR)
-#define UART_GET_MR(port) readl((port)->membase + AT91_US_MR)
-#define UART_PUT_MR(port,v) writel(v, (port)->membase + AT91_US_MR)
-#define UART_PUT_IER(port,v) writel(v, (port)->membase + AT91_US_IER)
-#define UART_PUT_IDR(port,v) writel(v, (port)->membase + AT91_US_IDR)
-#define UART_GET_IMR(port) readl((port)->membase + AT91_US_IMR)
-#define UART_GET_CSR(port) readl((port)->membase + AT91_US_CSR)
-#define UART_GET_CHAR(port) readl((port)->membase + AT91_US_RHR)
-#define UART_PUT_CHAR(port,v) writel(v, (port)->membase + AT91_US_THR)
-#define UART_GET_BRGR(port) readl((port)->membase + AT91_US_BRGR)
-#define UART_PUT_BRGR(port,v) writel(v, (port)->membase + AT91_US_BRGR)
-#define UART_PUT_RTOR(port,v) writel(v, (port)->membase + AT91_US_RTOR)
-
-// #define UART_GET_CR(port) readl((port)->membase + AT91_US_CR) // is write-only
+#define ATMEL_ISR_PASS_LIMIT 256
+
+/* UART registers. CR is write-only, hence no GET macro */
+#define UART_PUT_CR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_CR)
+#define UART_GET_MR(port) __raw_readl((port)->membase + ATMEL_US_MR)
+#define UART_PUT_MR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_MR)
+#define UART_PUT_IER(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IER)
+#define UART_PUT_IDR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IDR)
+#define UART_GET_IMR(port) __raw_readl((port)->membase + ATMEL_US_IMR)
+#define UART_GET_CSR(port) __raw_readl((port)->membase + ATMEL_US_CSR)
+#define UART_GET_CHAR(port) __raw_readl((port)->membase + ATMEL_US_RHR)
+#define UART_PUT_CHAR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_THR)
+#define UART_GET_BRGR(port) __raw_readl((port)->membase + ATMEL_US_BRGR)
+#define UART_PUT_BRGR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_BRGR)
+#define UART_PUT_RTOR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_RTOR)
/* PDC registers */
-#define UART_PUT_PTCR(port,v) writel(v, (port)->membase + AT91_PDC_PTCR)
-#define UART_GET_PTSR(port) readl((port)->membase + AT91_PDC_PTSR)
-
-#define UART_PUT_RPR(port,v) writel(v, (port)->membase + AT91_PDC_RPR)
-#define UART_GET_RPR(port) readl((port)->membase + AT91_PDC_RPR)
-#define UART_PUT_RCR(port,v) writel(v, (port)->membase + AT91_PDC_RCR)
-#define UART_PUT_RNPR(port,v) writel(v, (port)->membase + AT91_PDC_RNPR)
-#define UART_PUT_RNCR(port,v) writel(v, (port)->membase + AT91_PDC_RNCR)
+#define UART_PUT_PTCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
+#define UART_GET_PTSR(port) __raw_readl((port)->membase + ATMEL_PDC_PTSR)
+
+#define UART_PUT_RPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RPR)
+#define UART_GET_RPR(port) __raw_readl((port)->membase + ATMEL_PDC_RPR)
+#define UART_PUT_RCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RCR)
+#define UART_PUT_RNPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNPR)
+#define UART_PUT_RNCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNCR)
+
+#define UART_PUT_TPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TPR)
+#define UART_PUT_TCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TCR)
+#define UART_GET_TCR(port) __raw_readl((port)->membase + ATMEL_PDC_TCR)
+
+static int (*atmel_open_hook)(struct uart_port *);
+static void (*atmel_close_hook)(struct uart_port *);
+
+struct atmel_dma_buffer {
+ unsigned char *buf;
+ dma_addr_t dma_addr;
+ unsigned int dma_size;
+ unsigned int ofs;
+};
-#define UART_PUT_TPR(port,v) writel(v, (port)->membase + AT91_PDC_TPR)
-#define UART_PUT_TCR(port,v) writel(v, (port)->membase + AT91_PDC_TCR)
-//#define UART_PUT_TNPR(port,v) writel(v, (port)->membase + AT91_PDC_TNPR)
-//#define UART_PUT_TNCR(port,v) writel(v, (port)->membase + AT91_PDC_TNCR)
+struct atmel_uart_char {
+ u16 status;
+ u16 ch;
+};
-static int (*at91_open)(struct uart_port *);
-static void (*at91_close)(struct uart_port *);
+#define ATMEL_SERIAL_RINGSIZE 1024
/*
* We wrap our port structure around the generic uart_port.
*/
-struct at91_uart_port {
+struct atmel_uart_port {
struct uart_port uart; /* uart */
struct clk *clk; /* uart clock */
- unsigned short suspended; /* is port suspended? */
+ int may_wakeup; /* cached value of device_may_wakeup for times we need to disable it */
+ u32 backup_imr; /* IMR saved during suspend */
+ int break_active; /* break being received */
+
+ short use_dma_rx; /* enable PDC receiver */
+ short pdc_rx_idx; /* current PDC RX buffer */
+ struct atmel_dma_buffer pdc_rx[2]; /* PDC receier */
+
+ short use_dma_tx; /* enable PDC transmitter */
+ struct atmel_dma_buffer pdc_tx; /* PDC transmitter */
+
+ struct tasklet_struct tasklet;
+ unsigned int irq_status;
+ unsigned int irq_status_prev;
+
+ struct circ_buf rx_ring;
};
-static struct at91_uart_port at91_ports[AT91_NR_UART];
+static struct atmel_uart_port atmel_ports[ATMEL_MAX_UART];
#ifdef SUPPORT_SYSRQ
-static struct console at91_console;
+static struct console atmel_console;
+#endif
+
+static inline struct atmel_uart_port *
+to_atmel_uart_port(struct uart_port *uart)
+{
+ return container_of(uart, struct atmel_uart_port, uart);
+}
+
+#ifdef CONFIG_SERIAL_ATMEL_PDC
+static bool atmel_use_dma_rx(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ return atmel_port->use_dma_rx;
+}
+
+static bool atmel_use_dma_tx(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ return atmel_port->use_dma_tx;
+}
+#else
+static bool atmel_use_dma_rx(struct uart_port *port)
+{
+ return false;
+}
+
+static bool atmel_use_dma_tx(struct uart_port *port)
+{
+ return false;
+}
#endif
/*
* Return TIOCSER_TEMT when transmitter FIFO and Shift register is empty.
*/
-static u_int at91_tx_empty(struct uart_port *port)
+static u_int atmel_tx_empty(struct uart_port *port)
{
- return (UART_GET_CSR(port) & AT91_US_TXEMPTY) ? TIOCSER_TEMT : 0;
+ return (UART_GET_CSR(port) & ATMEL_US_TXEMPTY) ? TIOCSER_TEMT : 0;
}
/*
* Set state of the modem control output lines
*/
-static void at91_set_mctrl(struct uart_port *port, u_int mctrl)
+static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
{
unsigned int control = 0;
unsigned int mode;
- if (arch_identify() == ARCH_ID_AT91RM9200) {
+#ifdef CONFIG_ARCH_AT91RM9200
+ if (cpu_is_at91rm9200()) {
/*
- * AT91RM9200 Errata #39: RTS0 is not internally connected to PA21.
- * We need to drive the pin manually.
+ * AT91RM9200 Errata #39: RTS0 is not internally connected
+ * to PA21. We need to drive the pin manually.
*/
if (port->mapbase == AT91RM9200_BASE_US0) {
if (mctrl & TIOCM_RTS)
at91_set_gpio_value(AT91_PIN_PA21, 1);
}
}
+#endif
if (mctrl & TIOCM_RTS)
- control |= AT91_US_RTSEN;
+ control |= ATMEL_US_RTSEN;
else
- control |= AT91_US_RTSDIS;
+ control |= ATMEL_US_RTSDIS;
if (mctrl & TIOCM_DTR)
- control |= AT91_US_DTREN;
+ control |= ATMEL_US_DTREN;
else
- control |= AT91_US_DTRDIS;
+ control |= ATMEL_US_DTRDIS;
UART_PUT_CR(port, control);
/* Local loopback mode? */
- mode = UART_GET_MR(port) & ~AT91_US_CHMODE;
+ mode = UART_GET_MR(port) & ~ATMEL_US_CHMODE;
if (mctrl & TIOCM_LOOP)
- mode |= AT91_US_CHMODE_LOC_LOOP;
+ mode |= ATMEL_US_CHMODE_LOC_LOOP;
else
- mode |= AT91_US_CHMODE_NORMAL;
+ mode |= ATMEL_US_CHMODE_NORMAL;
UART_PUT_MR(port, mode);
}
/*
* Get state of the modem control input lines
*/
-static u_int at91_get_mctrl(struct uart_port *port)
+static u_int atmel_get_mctrl(struct uart_port *port)
{
unsigned int status, ret = 0;
/*
* The control signals are active low.
*/
- if (!(status & AT91_US_DCD))
+ if (!(status & ATMEL_US_DCD))
ret |= TIOCM_CD;
- if (!(status & AT91_US_CTS))
+ if (!(status & ATMEL_US_CTS))
ret |= TIOCM_CTS;
- if (!(status & AT91_US_DSR))
+ if (!(status & ATMEL_US_DSR))
ret |= TIOCM_DSR;
- if (!(status & AT91_US_RI))
+ if (!(status & ATMEL_US_RI))
ret |= TIOCM_RI;
return ret;
/*
* Stop transmitting.
*/
-static void at91_stop_tx(struct uart_port *port)
+static void atmel_stop_tx(struct uart_port *port)
{
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
-
- UART_PUT_IDR(port, AT91_US_TXRDY);
+ if (atmel_use_dma_tx(port)) {
+ /* disable PDC transmit */
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+ UART_PUT_IDR(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
+ } else
+ UART_PUT_IDR(port, ATMEL_US_TXRDY);
}
/*
* Start transmitting.
*/
-static void at91_start_tx(struct uart_port *port)
+static void atmel_start_tx(struct uart_port *port)
{
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
-
- UART_PUT_IER(port, AT91_US_TXRDY);
+ if (atmel_use_dma_tx(port)) {
+ if (UART_GET_PTSR(port) & ATMEL_PDC_TXTEN)
+ /* The transmitter is already running. Yes, we
+ really need this.*/
+ return;
+
+ UART_PUT_IER(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
+ /* re-enable PDC transmit */
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+ } else
+ UART_PUT_IER(port, ATMEL_US_TXRDY);
}
/*
* Stop receiving - port is in process of being closed.
*/
-static void at91_stop_rx(struct uart_port *port)
+static void atmel_stop_rx(struct uart_port *port)
{
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
-
- UART_PUT_IDR(port, AT91_US_RXRDY);
+ if (atmel_use_dma_rx(port)) {
+ /* disable PDC receive */
+ UART_PUT_PTCR(port, ATMEL_PDC_RXTDIS);
+ UART_PUT_IDR(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+ } else
+ UART_PUT_IDR(port, ATMEL_US_RXRDY);
}
/*
* Enable modem status interrupts
*/
-static void at91_enable_ms(struct uart_port *port)
+static void atmel_enable_ms(struct uart_port *port)
{
- UART_PUT_IER(port, AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC);
+ UART_PUT_IER(port, ATMEL_US_RIIC | ATMEL_US_DSRIC
+ | ATMEL_US_DCDIC | ATMEL_US_CTSIC);
}
/*
* Control the transmission of a break signal
*/
-static void at91_break_ctl(struct uart_port *port, int break_state)
+static void atmel_break_ctl(struct uart_port *port, int break_state)
{
if (break_state != 0)
- UART_PUT_CR(port, AT91_US_STTBRK); /* start break */
+ UART_PUT_CR(port, ATMEL_US_STTBRK); /* start break */
else
- UART_PUT_CR(port, AT91_US_STPBRK); /* stop break */
+ UART_PUT_CR(port, ATMEL_US_STPBRK); /* stop break */
+}
+
+/*
+ * Stores the incoming character in the ring buffer
+ */
+static void
+atmel_buffer_rx_char(struct uart_port *port, unsigned int status,
+ unsigned int ch)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ struct circ_buf *ring = &atmel_port->rx_ring;
+ struct atmel_uart_char *c;
+
+ if (!CIRC_SPACE(ring->head, ring->tail, ATMEL_SERIAL_RINGSIZE))
+ /* Buffer overflow, ignore char */
+ return;
+
+ c = &((struct atmel_uart_char *)ring->buf)[ring->head];
+ c->status = status;
+ c->ch = ch;
+
+ /* Make sure the character is stored before we update head. */
+ smp_wmb();
+
+ ring->head = (ring->head + 1) & (ATMEL_SERIAL_RINGSIZE - 1);
+}
+
+/*
+ * Deal with parity, framing and overrun errors.
+ */
+static void atmel_pdc_rxerr(struct uart_port *port, unsigned int status)
+{
+ /* clear error */
+ UART_PUT_CR(port, ATMEL_US_RSTSTA);
+
+ if (status & ATMEL_US_RXBRK) {
+ /* ignore side-effect */
+ status &= ~(ATMEL_US_PARE | ATMEL_US_FRAME);
+ port->icount.brk++;
+ }
+ if (status & ATMEL_US_PARE)
+ port->icount.parity++;
+ if (status & ATMEL_US_FRAME)
+ port->icount.frame++;
+ if (status & ATMEL_US_OVRE)
+ port->icount.overrun++;
}
/*
* Characters received (called from interrupt handler)
*/
-static void at91_rx_chars(struct uart_port *port, struct pt_regs *regs)
+static void atmel_rx_chars(struct uart_port *port)
{
- struct tty_struct *tty = port->info->tty;
- unsigned int status, ch, flg;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ unsigned int status, ch;
status = UART_GET_CSR(port);
- while (status & AT91_US_RXRDY) {
+ while (status & ATMEL_US_RXRDY) {
ch = UART_GET_CHAR(port);
- port->icount.rx++;
-
- flg = TTY_NORMAL;
-
/*
* note that the error handling code is
* out of the main execution path
*/
- if (unlikely(status & (AT91_US_PARE | AT91_US_FRAME | AT91_US_OVRE | AT91_US_RXBRK))) {
- UART_PUT_CR(port, AT91_US_RSTSTA); /* clear error */
- if (status & AT91_US_RXBRK) {
- status &= ~(AT91_US_PARE | AT91_US_FRAME); /* ignore side-effect */
- port->icount.brk++;
- if (uart_handle_break(port))
- goto ignore_char;
+ if (unlikely(status & (ATMEL_US_PARE | ATMEL_US_FRAME
+ | ATMEL_US_OVRE | ATMEL_US_RXBRK)
+ || atmel_port->break_active)) {
+
+ /* clear error */
+ UART_PUT_CR(port, ATMEL_US_RSTSTA);
+
+ if (status & ATMEL_US_RXBRK
+ && !atmel_port->break_active) {
+ atmel_port->break_active = 1;
+ UART_PUT_IER(port, ATMEL_US_RXBRK);
+ } else {
+ /*
+ * This is either the end-of-break
+ * condition or we've received at
+ * least one character without RXBRK
+ * being set. In both cases, the next
+ * RXBRK will indicate start-of-break.
+ */
+ UART_PUT_IDR(port, ATMEL_US_RXBRK);
+ status &= ~ATMEL_US_RXBRK;
+ atmel_port->break_active = 0;
}
- if (status & AT91_US_PARE)
- port->icount.parity++;
- if (status & AT91_US_FRAME)
- port->icount.frame++;
- if (status & AT91_US_OVRE)
- port->icount.overrun++;
-
- status &= port->read_status_mask;
-
- if (status & AT91_US_RXBRK)
- flg = TTY_BREAK;
- else if (status & AT91_US_PARE)
- flg = TTY_PARITY;
- else if (status & AT91_US_FRAME)
- flg = TTY_FRAME;
}
- if (uart_handle_sysrq_char(port, ch, regs))
- goto ignore_char;
-
- uart_insert_char(port, status, AT91_US_OVRE, ch, flg);
-
- ignore_char:
+ atmel_buffer_rx_char(port, status, ch);
status = UART_GET_CSR(port);
}
- tty_flip_buffer_push(tty);
+ tasklet_schedule(&atmel_port->tasklet);
}
/*
- * Transmit characters (called from interrupt handler)
+ * Transmit characters (called from tasklet with TXRDY interrupt
+ * disabled)
*/
-static void at91_tx_chars(struct uart_port *port)
+static void atmel_tx_chars(struct uart_port *port)
{
- struct circ_buf *xmit = &port->info->xmit;
+ struct circ_buf *xmit = &port->state->xmit;
- if (port->x_char) {
+ if (port->x_char && UART_GET_CSR(port) & ATMEL_US_TXRDY) {
UART_PUT_CHAR(port, port->x_char);
port->icount.tx++;
port->x_char = 0;
- return;
}
- if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
- at91_stop_tx(port);
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port))
return;
- }
- while (UART_GET_CSR(port) & AT91_US_TXRDY) {
+ while (UART_GET_CSR(port) & ATMEL_US_TXRDY) {
UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
- if (uart_circ_empty(xmit))
- at91_stop_tx(port);
+ if (!uart_circ_empty(xmit))
+ UART_PUT_IER(port, ATMEL_US_TXRDY);
}
/*
- * Interrupt handler
+ * receive interrupt handler.
*/
-static irqreturn_t at91_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+static void
+atmel_handle_receive(struct uart_port *port, unsigned int pending)
{
- struct uart_port *port = dev_id;
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
- unsigned int status, pending, pass_counter = 0;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- status = UART_GET_CSR(port);
- pending = status & UART_GET_IMR(port);
- while (pending) {
- /* Interrupt receive */
- if (pending & AT91_US_RXRDY)
- at91_rx_chars(port, regs);
-
- // TODO: All reads to CSR will clear these interrupts!
- if (pending & AT91_US_RIIC) port->icount.rng++;
- if (pending & AT91_US_DSRIC) port->icount.dsr++;
- if (pending & AT91_US_DCDIC)
- uart_handle_dcd_change(port, !(status & AT91_US_DCD));
- if (pending & AT91_US_CTSIC)
- uart_handle_cts_change(port, !(status & AT91_US_CTS));
- if (pending & (AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC))
- wake_up_interruptible(&port->info->delta_msr_wait);
+ if (atmel_use_dma_rx(port)) {
+ /*
+ * PDC receive. Just schedule the tasklet and let it
+ * figure out the details.
+ *
+ * TODO: We're not handling error flags correctly at
+ * the moment.
+ */
+ if (pending & (ATMEL_US_ENDRX | ATMEL_US_TIMEOUT)) {
+ UART_PUT_IDR(port, (ATMEL_US_ENDRX
+ | ATMEL_US_TIMEOUT));
+ tasklet_schedule(&atmel_port->tasklet);
+ }
+ if (pending & (ATMEL_US_RXBRK | ATMEL_US_OVRE |
+ ATMEL_US_FRAME | ATMEL_US_PARE))
+ atmel_pdc_rxerr(port, pending);
+ }
+
+ /* Interrupt receive */
+ if (pending & ATMEL_US_RXRDY)
+ atmel_rx_chars(port);
+ else if (pending & ATMEL_US_RXBRK) {
+ /*
+ * End of break detected. If it came along with a
+ * character, atmel_rx_chars will handle it.
+ */
+ UART_PUT_CR(port, ATMEL_US_RSTSTA);
+ UART_PUT_IDR(port, ATMEL_US_RXBRK);
+ atmel_port->break_active = 0;
+ }
+}
+
+/*
+ * transmit interrupt handler. (Transmit is IRQF_NODELAY safe)
+ */
+static void
+atmel_handle_transmit(struct uart_port *port, unsigned int pending)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ if (atmel_use_dma_tx(port)) {
+ /* PDC transmit */
+ if (pending & (ATMEL_US_ENDTX | ATMEL_US_TXBUFE)) {
+ UART_PUT_IDR(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
+ tasklet_schedule(&atmel_port->tasklet);
+ }
+ } else {
/* Interrupt transmit */
- if (pending & AT91_US_TXRDY)
- at91_tx_chars(port);
+ if (pending & ATMEL_US_TXRDY) {
+ UART_PUT_IDR(port, ATMEL_US_TXRDY);
+ tasklet_schedule(&atmel_port->tasklet);
+ }
+ }
+}
- if (pass_counter++ > AT91_ISR_PASS_LIMIT)
- break;
+/*
+ * status flags interrupt handler.
+ */
+static void
+atmel_handle_status(struct uart_port *port, unsigned int pending,
+ unsigned int status)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ if (pending & (ATMEL_US_RIIC | ATMEL_US_DSRIC | ATMEL_US_DCDIC
+ | ATMEL_US_CTSIC)) {
+ atmel_port->irq_status = status;
+ tasklet_schedule(&atmel_port->tasklet);
+ }
+}
+
+/*
+ * Interrupt handler
+ */
+static irqreturn_t atmel_interrupt(int irq, void *dev_id)
+{
+ struct uart_port *port = dev_id;
+ unsigned int status, pending, pass_counter = 0;
+ do {
status = UART_GET_CSR(port);
pending = status & UART_GET_IMR(port);
+ if (!pending)
+ break;
+
+ atmel_handle_receive(port, pending);
+ atmel_handle_status(port, pending, status);
+ atmel_handle_transmit(port, pending);
+ } while (pass_counter++ < ATMEL_ISR_PASS_LIMIT);
+
+ return pass_counter ? IRQ_HANDLED : IRQ_NONE;
+}
+
+/*
+ * Called from tasklet with ENDTX and TXBUFE interrupts disabled.
+ */
+static void atmel_tx_dma(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ struct circ_buf *xmit = &port->state->xmit;
+ struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
+ int count;
+
+ /* nothing left to transmit? */
+ if (UART_GET_TCR(port))
+ return;
+
+ xmit->tail += pdc->ofs;
+ xmit->tail &= UART_XMIT_SIZE - 1;
+
+ port->icount.tx += pdc->ofs;
+ pdc->ofs = 0;
+
+ /* more to transmit - setup next transfer */
+
+ /* disable PDC transmit */
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+
+ if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) {
+ dma_sync_single_for_device(port->dev,
+ pdc->dma_addr,
+ pdc->dma_size,
+ DMA_TO_DEVICE);
+
+ count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+ pdc->ofs = count;
+
+ UART_PUT_TPR(port, pdc->dma_addr + xmit->tail);
+ UART_PUT_TCR(port, count);
+ /* re-enable PDC transmit and interrupts */
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+ UART_PUT_IER(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+}
+
+static void atmel_rx_from_ring(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ struct circ_buf *ring = &atmel_port->rx_ring;
+ unsigned int flg;
+ unsigned int status;
+
+ while (ring->head != ring->tail) {
+ struct atmel_uart_char c;
+
+ /* Make sure c is loaded after head. */
+ smp_rmb();
+
+ c = ((struct atmel_uart_char *)ring->buf)[ring->tail];
+
+ ring->tail = (ring->tail + 1) & (ATMEL_SERIAL_RINGSIZE - 1);
+
+ port->icount.rx++;
+ status = c.status;
+ flg = TTY_NORMAL;
+
+ /*
+ * note that the error handling code is
+ * out of the main execution path
+ */
+ if (unlikely(status & (ATMEL_US_PARE | ATMEL_US_FRAME
+ | ATMEL_US_OVRE | ATMEL_US_RXBRK))) {
+ if (status & ATMEL_US_RXBRK) {
+ /* ignore side-effect */
+ status &= ~(ATMEL_US_PARE | ATMEL_US_FRAME);
+
+ port->icount.brk++;
+ if (uart_handle_break(port))
+ continue;
+ }
+ if (status & ATMEL_US_PARE)
+ port->icount.parity++;
+ if (status & ATMEL_US_FRAME)
+ port->icount.frame++;
+ if (status & ATMEL_US_OVRE)
+ port->icount.overrun++;
+
+ status &= port->read_status_mask;
+
+ if (status & ATMEL_US_RXBRK)
+ flg = TTY_BREAK;
+ else if (status & ATMEL_US_PARE)
+ flg = TTY_PARITY;
+ else if (status & ATMEL_US_FRAME)
+ flg = TTY_FRAME;
+ }
+
+
+ if (uart_handle_sysrq_char(port, c.ch))
+ continue;
+
+ uart_insert_char(port, status, ATMEL_US_OVRE, c.ch, flg);
}
- return IRQ_HANDLED;
+
+ /*
+ * Drop the lock here since it might end up calling
+ * uart_start(), which takes the lock.
+ */
+ spin_unlock(&port->lock);
+ tty_flip_buffer_push(port->state->port.tty);
+ spin_lock(&port->lock);
+}
+
+static void atmel_rx_from_dma(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ struct tty_struct *tty = port->state->port.tty;
+ struct atmel_dma_buffer *pdc;
+ int rx_idx = atmel_port->pdc_rx_idx;
+ unsigned int head;
+ unsigned int tail;
+ unsigned int count;
+
+ do {
+ /* Reset the UART timeout early so that we don't miss one */
+ UART_PUT_CR(port, ATMEL_US_STTTO);
+
+ pdc = &atmel_port->pdc_rx[rx_idx];
+ head = UART_GET_RPR(port) - pdc->dma_addr;
+ tail = pdc->ofs;
+
+ /* If the PDC has switched buffers, RPR won't contain
+ * any address within the current buffer. Since head
+ * is unsigned, we just need a one-way comparison to
+ * find out.
+ *
+ * In this case, we just need to consume the entire
+ * buffer and resubmit it for DMA. This will clear the
+ * ENDRX bit as well, so that we can safely re-enable
+ * all interrupts below.
+ */
+ head = min(head, pdc->dma_size);
+
+ if (likely(head != tail)) {
+ dma_sync_single_for_cpu(port->dev, pdc->dma_addr,
+ pdc->dma_size, DMA_FROM_DEVICE);
+
+ /*
+ * head will only wrap around when we recycle
+ * the DMA buffer, and when that happens, we
+ * explicitly set tail to 0. So head will
+ * always be greater than tail.
+ */
+ count = head - tail;
+
+ tty_insert_flip_string(tty, pdc->buf + pdc->ofs, count);
+
+ dma_sync_single_for_device(port->dev, pdc->dma_addr,
+ pdc->dma_size, DMA_FROM_DEVICE);
+
+ port->icount.rx += count;
+ pdc->ofs = head;
+ }
+
+ /*
+ * If the current buffer is full, we need to check if
+ * the next one contains any additional data.
+ */
+ if (head >= pdc->dma_size) {
+ pdc->ofs = 0;
+ UART_PUT_RNPR(port, pdc->dma_addr);
+ UART_PUT_RNCR(port, pdc->dma_size);
+
+ rx_idx = !rx_idx;
+ atmel_port->pdc_rx_idx = rx_idx;
+ }
+ } while (head >= pdc->dma_size);
+
+ /*
+ * Drop the lock here since it might end up calling
+ * uart_start(), which takes the lock.
+ */
+ spin_unlock(&port->lock);
+ tty_flip_buffer_push(tty);
+ spin_lock(&port->lock);
+
+ UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+}
+
+/*
+ * tasklet handling tty stuff outside the interrupt handler.
+ */
+static void atmel_tasklet_func(unsigned long data)
+{
+ struct uart_port *port = (struct uart_port *)data;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ unsigned int status;
+ unsigned int status_change;
+
+ /* The interrupt handler does not take the lock */
+ spin_lock(&port->lock);
+
+ if (atmel_use_dma_tx(port))
+ atmel_tx_dma(port);
+ else
+ atmel_tx_chars(port);
+
+ status = atmel_port->irq_status;
+ status_change = status ^ atmel_port->irq_status_prev;
+
+ if (status_change & (ATMEL_US_RI | ATMEL_US_DSR
+ | ATMEL_US_DCD | ATMEL_US_CTS)) {
+ /* TODO: All reads to CSR will clear these interrupts! */
+ if (status_change & ATMEL_US_RI)
+ port->icount.rng++;
+ if (status_change & ATMEL_US_DSR)
+ port->icount.dsr++;
+ if (status_change & ATMEL_US_DCD)
+ uart_handle_dcd_change(port, !(status & ATMEL_US_DCD));
+ if (status_change & ATMEL_US_CTS)
+ uart_handle_cts_change(port, !(status & ATMEL_US_CTS));
+
+ wake_up_interruptible(&port->state->port.delta_msr_wait);
+
+ atmel_port->irq_status_prev = status;
+ }
+
+ if (atmel_use_dma_rx(port))
+ atmel_rx_from_dma(port);
+ else
+ atmel_rx_from_ring(port);
+
+ spin_unlock(&port->lock);
}
/*
* Perform initialization and enable port for reception
*/
-static int at91_startup(struct uart_port *port)
+static int atmel_startup(struct uart_port *port)
{
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ struct tty_struct *tty = port->state->port.tty;
int retval;
/*
/*
* Allocate the IRQ
*/
- retval = request_irq(port->irq, at91_interrupt, IRQF_SHARED, "at91_serial", port);
+ retval = request_irq(port->irq, atmel_interrupt, IRQF_SHARED,
+ tty ? tty->name : "atmel_serial", port);
if (retval) {
- printk("at91_serial: at91_startup - Can't get irq\n");
+ printk("atmel_serial: atmel_startup - Can't get irq\n");
return retval;
}
/*
+ * Initialize DMA (if necessary)
+ */
+ if (atmel_use_dma_rx(port)) {
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
+
+ pdc->buf = kmalloc(PDC_BUFFER_SIZE, GFP_KERNEL);
+ if (pdc->buf == NULL) {
+ if (i != 0) {
+ dma_unmap_single(port->dev,
+ atmel_port->pdc_rx[0].dma_addr,
+ PDC_BUFFER_SIZE,
+ DMA_FROM_DEVICE);
+ kfree(atmel_port->pdc_rx[0].buf);
+ }
+ free_irq(port->irq, port);
+ return -ENOMEM;
+ }
+ pdc->dma_addr = dma_map_single(port->dev,
+ pdc->buf,
+ PDC_BUFFER_SIZE,
+ DMA_FROM_DEVICE);
+ pdc->dma_size = PDC_BUFFER_SIZE;
+ pdc->ofs = 0;
+ }
+
+ atmel_port->pdc_rx_idx = 0;
+
+ UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr);
+ UART_PUT_RCR(port, PDC_BUFFER_SIZE);
+
+ UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr);
+ UART_PUT_RNCR(port, PDC_BUFFER_SIZE);
+ }
+ if (atmel_use_dma_tx(port)) {
+ struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
+ struct circ_buf *xmit = &port->state->xmit;
+
+ pdc->buf = xmit->buf;
+ pdc->dma_addr = dma_map_single(port->dev,
+ pdc->buf,
+ UART_XMIT_SIZE,
+ DMA_TO_DEVICE);
+ pdc->dma_size = UART_XMIT_SIZE;
+ pdc->ofs = 0;
+ }
+
+ /*
* If there is a specific "open" function (to register
* control line interrupts)
*/
- if (at91_open) {
- retval = at91_open(port);
+ if (atmel_open_hook) {
+ retval = atmel_open_hook(port);
if (retval) {
free_irq(port->irq, port);
return retval;
}
}
+ /* Save current CSR for comparison in atmel_tasklet_func() */
+ atmel_port->irq_status_prev = UART_GET_CSR(port);
+ atmel_port->irq_status = atmel_port->irq_status_prev;
+
/*
* Finally, enable the serial port
*/
- UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX);
- UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN); /* enable xmit & rcvr */
-
- UART_PUT_IER(port, AT91_US_RXRDY); /* enable receive only */
+ UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+ /* enable xmit & rcvr */
+ UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
+
+ if (atmel_use_dma_rx(port)) {
+ /* set UART timeout */
+ UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
+ UART_PUT_CR(port, ATMEL_US_STTTO);
+
+ UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+ /* enable PDC controller */
+ UART_PUT_PTCR(port, ATMEL_PDC_RXTEN);
+ } else {
+ /* enable receive only */
+ UART_PUT_IER(port, ATMEL_US_RXRDY);
+ }
return 0;
}
/*
* Disable the port
*/
-static void at91_shutdown(struct uart_port *port)
+static void atmel_shutdown(struct uart_port *port)
{
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ /*
+ * Ensure everything is stopped.
+ */
+ atmel_stop_rx(port);
+ atmel_stop_tx(port);
+
+ /*
+ * Shut-down the DMA.
+ */
+ if (atmel_use_dma_rx(port)) {
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
+
+ dma_unmap_single(port->dev,
+ pdc->dma_addr,
+ pdc->dma_size,
+ DMA_FROM_DEVICE);
+ kfree(pdc->buf);
+ }
+ }
+ if (atmel_use_dma_tx(port)) {
+ struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
+
+ dma_unmap_single(port->dev,
+ pdc->dma_addr,
+ pdc->dma_size,
+ DMA_TO_DEVICE);
+ }
/*
* Disable all interrupts, port and break condition.
*/
- UART_PUT_CR(port, AT91_US_RSTSTA);
+ UART_PUT_CR(port, ATMEL_US_RSTSTA);
UART_PUT_IDR(port, -1);
/*
* If there is a specific "close" function (to unregister
* control line interrupts)
*/
- if (at91_close)
- at91_close(port);
+ if (atmel_close_hook)
+ atmel_close_hook(port);
+}
+
+/*
+ * Flush any TX data submitted for DMA. Called when the TX circular
+ * buffer is reset.
+ */
+static void atmel_flush_buffer(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ if (atmel_use_dma_tx(port)) {
+ UART_PUT_TCR(port, 0);
+ atmel_port->pdc_tx.ofs = 0;
+ }
}
/*
* Power / Clock management.
*/
-static void at91_serial_pm(struct uart_port *port, unsigned int state, unsigned int oldstate)
+static void atmel_serial_pm(struct uart_port *port, unsigned int state,
+ unsigned int oldstate)
{
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
switch (state) {
- case 0:
- /*
- * Enable the peripheral clock for this serial port.
- * This is called on uart_open() or a resume event.
- */
- clk_enable(at91_port->clk);
- break;
- case 3:
- /*
- * Disable the peripheral clock for this serial port.
- * This is called on uart_close() or a suspend event.
- */
- clk_disable(at91_port->clk);
- break;
- default:
- printk(KERN_ERR "at91_serial: unknown pm %d\n", state);
+ case 0:
+ /*
+ * Enable the peripheral clock for this serial port.
+ * This is called on uart_open() or a resume event.
+ */
+ clk_enable(atmel_port->clk);
+
+ /* re-enable interrupts if we disabled some on suspend */
+ UART_PUT_IER(port, atmel_port->backup_imr);
+ break;
+ case 3:
+ /* Back up the interrupt mask and disable all interrupts */
+ atmel_port->backup_imr = UART_GET_IMR(port);
+ UART_PUT_IDR(port, -1);
+
+ /*
+ * Disable the peripheral clock for this serial port.
+ * This is called on uart_close() or a suspend event.
+ */
+ clk_disable(atmel_port->clk);
+ break;
+ default:
+ printk(KERN_ERR "atmel_serial: unknown pm %d\n", state);
}
}
/*
* Change the port parameters
*/
-static void at91_set_termios(struct uart_port *port, struct termios * termios, struct termios * old)
+static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
+ struct ktermios *old)
{
unsigned long flags;
unsigned int mode, imr, quot, baud;
- baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+ /* Get current mode register */
+ mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL
+ | ATMEL_US_NBSTOP | ATMEL_US_PAR
+ | ATMEL_US_USMODE);
+
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
quot = uart_get_divisor(port, baud);
- /* Get current mode register */
- mode = UART_GET_MR(port) & ~(AT91_US_CHRL | AT91_US_NBSTOP | AT91_US_PAR);
+ if (quot > 65535) { /* BRGR is 16-bit, so switch to slower clock */
+ quot /= 8;
+ mode |= ATMEL_US_USCLKS_MCK_DIV8;
+ }
/* byte size */
switch (termios->c_cflag & CSIZE) {
case CS5:
- mode |= AT91_US_CHRL_5;
+ mode |= ATMEL_US_CHRL_5;
break;
case CS6:
- mode |= AT91_US_CHRL_6;
+ mode |= ATMEL_US_CHRL_6;
break;
case CS7:
- mode |= AT91_US_CHRL_7;
+ mode |= ATMEL_US_CHRL_7;
break;
default:
- mode |= AT91_US_CHRL_8;
+ mode |= ATMEL_US_CHRL_8;
break;
}
/* stop bits */
if (termios->c_cflag & CSTOPB)
- mode |= AT91_US_NBSTOP_2;
+ mode |= ATMEL_US_NBSTOP_2;
/* parity */
if (termios->c_cflag & PARENB) {
- if (termios->c_cflag & CMSPAR) { /* Mark or Space parity */
+ /* Mark or Space parity */
+ if (termios->c_cflag & CMSPAR) {
if (termios->c_cflag & PARODD)
- mode |= AT91_US_PAR_MARK;
+ mode |= ATMEL_US_PAR_MARK;
else
- mode |= AT91_US_PAR_SPACE;
- }
- else if (termios->c_cflag & PARODD)
- mode |= AT91_US_PAR_ODD;
+ mode |= ATMEL_US_PAR_SPACE;
+ } else if (termios->c_cflag & PARODD)
+ mode |= ATMEL_US_PAR_ODD;
else
- mode |= AT91_US_PAR_EVEN;
- }
+ mode |= ATMEL_US_PAR_EVEN;
+ } else
+ mode |= ATMEL_US_PAR_NONE;
+
+ /* hardware handshake (RTS/CTS) */
+ if (termios->c_cflag & CRTSCTS)
+ mode |= ATMEL_US_USMODE_HWHS;
else
- mode |= AT91_US_PAR_NONE;
+ mode |= ATMEL_US_USMODE_NORMAL;
spin_lock_irqsave(&port->lock, flags);
- port->read_status_mask = AT91_US_OVRE;
+ port->read_status_mask = ATMEL_US_OVRE;
if (termios->c_iflag & INPCK)
- port->read_status_mask |= (AT91_US_FRAME | AT91_US_PARE);
+ port->read_status_mask |= (ATMEL_US_FRAME | ATMEL_US_PARE);
if (termios->c_iflag & (BRKINT | PARMRK))
- port->read_status_mask |= AT91_US_RXBRK;
+ port->read_status_mask |= ATMEL_US_RXBRK;
+
+ if (atmel_use_dma_rx(port))
+ /* need to enable error interrupts */
+ UART_PUT_IER(port, port->read_status_mask);
/*
* Characters to ignore
*/
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
- port->ignore_status_mask |= (AT91_US_FRAME | AT91_US_PARE);
+ port->ignore_status_mask |= (ATMEL_US_FRAME | ATMEL_US_PARE);
if (termios->c_iflag & IGNBRK) {
- port->ignore_status_mask |= AT91_US_RXBRK;
+ port->ignore_status_mask |= ATMEL_US_RXBRK;
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (termios->c_iflag & IGNPAR)
- port->ignore_status_mask |= AT91_US_OVRE;
+ port->ignore_status_mask |= ATMEL_US_OVRE;
}
-
- // TODO: Ignore all characters if CREAD is set.
+ /* TODO: Ignore all characters if CREAD is set.*/
/* update the per-port timeout */
uart_update_timeout(port, termios->c_cflag, baud);
- /* disable interrupts and drain transmitter */
- imr = UART_GET_IMR(port); /* get interrupt mask */
- UART_PUT_IDR(port, -1); /* disable all interrupts */
- while (!(UART_GET_CSR(port) & AT91_US_TXEMPTY)) { barrier(); }
+ /*
+ * save/disable interrupts. The tty layer will ensure that the
+ * transmitter is empty if requested by the caller, so there's
+ * no need to wait for it here.
+ */
+ imr = UART_GET_IMR(port);
+ UART_PUT_IDR(port, -1);
/* disable receiver and transmitter */
- UART_PUT_CR(port, AT91_US_TXDIS | AT91_US_RXDIS);
+ UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS);
/* set the parity, stop bits and data size */
UART_PUT_MR(port, mode);
/* set the baud rate */
UART_PUT_BRGR(port, quot);
- UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX);
- UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN);
+ UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+ UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
/* restore interrupts */
UART_PUT_IER(port, imr);
/*
* Return string describing the specified port
*/
-static const char *at91_type(struct uart_port *port)
+static const char *atmel_type(struct uart_port *port)
{
- return (port->type == PORT_AT91) ? "AT91_SERIAL" : NULL;
+ return (port->type == PORT_ATMEL) ? "ATMEL_SERIAL" : NULL;
}
/*
* Release the memory region(s) being used by 'port'.
*/
-static void at91_release_port(struct uart_port *port)
+static void atmel_release_port(struct uart_port *port)
{
struct platform_device *pdev = to_platform_device(port->dev);
int size = pdev->resource[0].end - pdev->resource[0].start + 1;
/*
* Request the memory region(s) being used by 'port'.
*/
-static int at91_request_port(struct uart_port *port)
+static int atmel_request_port(struct uart_port *port)
{
struct platform_device *pdev = to_platform_device(port->dev);
int size = pdev->resource[0].end - pdev->resource[0].start + 1;
- if (!request_mem_region(port->mapbase, size, "at91_serial"))
+ if (!request_mem_region(port->mapbase, size, "atmel_serial"))
return -EBUSY;
if (port->flags & UPF_IOREMAP) {
/*
* Configure/autoconfigure the port.
*/
-static void at91_config_port(struct uart_port *port, int flags)
+static void atmel_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE) {
- port->type = PORT_AT91;
- at91_request_port(port);
+ port->type = PORT_ATMEL;
+ atmel_request_port(port);
}
}
/*
* Verify the new serial_struct (for TIOCSSERIAL).
*/
-static int at91_verify_port(struct uart_port *port, struct serial_struct *ser)
+static int atmel_verify_port(struct uart_port *port, struct serial_struct *ser)
{
int ret = 0;
- if (ser->type != PORT_UNKNOWN && ser->type != PORT_AT91)
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_ATMEL)
ret = -EINVAL;
if (port->irq != ser->irq)
ret = -EINVAL;
return ret;
}
-static struct uart_ops at91_pops = {
- .tx_empty = at91_tx_empty,
- .set_mctrl = at91_set_mctrl,
- .get_mctrl = at91_get_mctrl,
- .stop_tx = at91_stop_tx,
- .start_tx = at91_start_tx,
- .stop_rx = at91_stop_rx,
- .enable_ms = at91_enable_ms,
- .break_ctl = at91_break_ctl,
- .startup = at91_startup,
- .shutdown = at91_shutdown,
- .set_termios = at91_set_termios,
- .type = at91_type,
- .release_port = at91_release_port,
- .request_port = at91_request_port,
- .config_port = at91_config_port,
- .verify_port = at91_verify_port,
- .pm = at91_serial_pm,
+#ifdef CONFIG_CONSOLE_POLL
+static int atmel_poll_get_char(struct uart_port *port)
+{
+ while (!(UART_GET_CSR(port) & ATMEL_US_RXRDY))
+ cpu_relax();
+
+ return UART_GET_CHAR(port);
+}
+
+static void atmel_poll_put_char(struct uart_port *port, unsigned char ch)
+{
+ while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY))
+ cpu_relax();
+
+ UART_PUT_CHAR(port, ch);
+}
+#endif
+
+static struct uart_ops atmel_pops = {
+ .tx_empty = atmel_tx_empty,
+ .set_mctrl = atmel_set_mctrl,
+ .get_mctrl = atmel_get_mctrl,
+ .stop_tx = atmel_stop_tx,
+ .start_tx = atmel_start_tx,
+ .stop_rx = atmel_stop_rx,
+ .enable_ms = atmel_enable_ms,
+ .break_ctl = atmel_break_ctl,
+ .startup = atmel_startup,
+ .shutdown = atmel_shutdown,
+ .flush_buffer = atmel_flush_buffer,
+ .set_termios = atmel_set_termios,
+ .type = atmel_type,
+ .release_port = atmel_release_port,
+ .request_port = atmel_request_port,
+ .config_port = atmel_config_port,
+ .verify_port = atmel_verify_port,
+ .pm = atmel_serial_pm,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = atmel_poll_get_char,
+ .poll_put_char = atmel_poll_put_char,
+#endif
};
/*
* Configure the port from the platform device resource info.
*/
-static void __devinit at91_init_port(struct at91_uart_port *at91_port, struct platform_device *pdev)
+static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port,
+ struct platform_device *pdev)
{
- struct uart_port *port = &at91_port->uart;
- struct at91_uart_data *data = pdev->dev.platform_data;
+ struct uart_port *port = &atmel_port->uart;
+ struct atmel_uart_data *data = pdev->dev.platform_data;
port->iotype = UPIO_MEM;
- port->flags = UPF_BOOT_AUTOCONF;
- port->ops = &at91_pops;
- port->fifosize = 1;
+ port->flags = UPF_BOOT_AUTOCONF;
+ port->ops = &atmel_pops;
+ port->fifosize = 1;
port->line = pdev->id;
port->dev = &pdev->dev;
port->mapbase = pdev->resource[0].start;
port->irq = pdev->resource[1].start;
- if (port->mapbase == AT91_VA_BASE_SYS + AT91_DBGU) /* Part of system perpherals - already mapped */
- port->membase = (void __iomem *) port->mapbase;
+ tasklet_init(&atmel_port->tasklet, atmel_tasklet_func,
+ (unsigned long)port);
+
+ memset(&atmel_port->rx_ring, 0, sizeof(atmel_port->rx_ring));
+
+ if (data->regs)
+ /* Already mapped by setup code */
+ port->membase = data->regs;
else {
port->flags |= UPF_IOREMAP;
port->membase = NULL;
}
- if (!at91_port->clk) { /* for console, the clock could already be configured */
- at91_port->clk = clk_get(&pdev->dev, "usart");
- clk_enable(at91_port->clk);
- port->uartclk = clk_get_rate(at91_port->clk);
+ /* for console, the clock could already be configured */
+ if (!atmel_port->clk) {
+ atmel_port->clk = clk_get(&pdev->dev, "usart");
+ clk_enable(atmel_port->clk);
+ port->uartclk = clk_get_rate(atmel_port->clk);
+ clk_disable(atmel_port->clk);
+ /* only enable clock when USART is in use */
}
+
+ atmel_port->use_dma_rx = data->use_dma_rx;
+ atmel_port->use_dma_tx = data->use_dma_tx;
+ if (atmel_use_dma_tx(port))
+ port->fifosize = PDC_BUFFER_SIZE;
}
/*
* Register board-specific modem-control line handlers.
*/
-void __init at91_register_uart_fns(struct at91_port_fns *fns)
+void __init atmel_register_uart_fns(struct atmel_port_fns *fns)
{
if (fns->enable_ms)
- at91_pops.enable_ms = fns->enable_ms;
+ atmel_pops.enable_ms = fns->enable_ms;
if (fns->get_mctrl)
- at91_pops.get_mctrl = fns->get_mctrl;
+ atmel_pops.get_mctrl = fns->get_mctrl;
if (fns->set_mctrl)
- at91_pops.set_mctrl = fns->set_mctrl;
- at91_open = fns->open;
- at91_close = fns->close;
- at91_pops.pm = fns->pm;
- at91_pops.set_wake = fns->set_wake;
+ atmel_pops.set_mctrl = fns->set_mctrl;
+ atmel_open_hook = fns->open;
+ atmel_close_hook = fns->close;
+ atmel_pops.pm = fns->pm;
+ atmel_pops.set_wake = fns->set_wake;
}
-
#ifdef CONFIG_SERIAL_ATMEL_CONSOLE
-static void at91_console_putchar(struct uart_port *port, int ch)
+static void atmel_console_putchar(struct uart_port *port, int ch)
{
- while (!(UART_GET_CSR(port) & AT91_US_TXRDY))
- barrier();
+ while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY))
+ cpu_relax();
UART_PUT_CHAR(port, ch);
}
/*
* Interrupts are disabled on entering
*/
-static void at91_console_write(struct console *co, const char *s, u_int count)
+static void atmel_console_write(struct console *co, const char *s, u_int count)
{
- struct uart_port *port = &at91_ports[co->index].uart;
+ struct uart_port *port = &atmel_ports[co->index].uart;
unsigned int status, imr;
+ unsigned int pdc_tx;
/*
- * First, save IMR and then disable interrupts
+ * First, save IMR and then disable interrupts
*/
- imr = UART_GET_IMR(port); /* get interrupt mask */
- UART_PUT_IDR(port, AT91_US_RXRDY | AT91_US_TXRDY);
+ imr = UART_GET_IMR(port);
+ UART_PUT_IDR(port, ATMEL_US_RXRDY | ATMEL_US_TXRDY);
+
+ /* Store PDC transmit status and disable it */
+ pdc_tx = UART_GET_PTSR(port) & ATMEL_PDC_TXTEN;
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
- uart_console_write(port, s, count, at91_console_putchar);
+ uart_console_write(port, s, count, atmel_console_putchar);
/*
- * Finally, wait for transmitter to become empty
- * and restore IMR
+ * Finally, wait for transmitter to become empty
+ * and restore IMR
*/
do {
status = UART_GET_CSR(port);
- } while (!(status & AT91_US_TXRDY));
- UART_PUT_IER(port, imr); /* set interrupts back the way they were */
+ } while (!(status & ATMEL_US_TXRDY));
+
+ /* Restore PDC transmit status */
+ if (pdc_tx)
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+
+ /* set interrupts back the way they were */
+ UART_PUT_IER(port, imr);
}
/*
- * If the port was already initialised (eg, by a boot loader), try to determine
- * the current setup.
+ * If the port was already initialised (eg, by a boot loader),
+ * try to determine the current setup.
*/
-static void __init at91_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits)
+static void __init atmel_console_get_options(struct uart_port *port, int *baud,
+ int *parity, int *bits)
{
unsigned int mr, quot;
-// TODO: CR is a write-only register
-// unsigned int cr;
-//
-// cr = UART_GET_CR(port) & (AT91_US_RXEN | AT91_US_TXEN);
-// if (cr == (AT91_US_RXEN | AT91_US_TXEN)) {
-// /* ok, the port was enabled */
-// }
+ /*
+ * If the baud rate generator isn't running, the port wasn't
+ * initialized by the boot loader.
+ */
+ quot = UART_GET_BRGR(port) & ATMEL_US_CD;
+ if (!quot)
+ return;
- mr = UART_GET_MR(port) & AT91_US_CHRL;
- if (mr == AT91_US_CHRL_8)
+ mr = UART_GET_MR(port) & ATMEL_US_CHRL;
+ if (mr == ATMEL_US_CHRL_8)
*bits = 8;
else
*bits = 7;
- mr = UART_GET_MR(port) & AT91_US_PAR;
- if (mr == AT91_US_PAR_EVEN)
+ mr = UART_GET_MR(port) & ATMEL_US_PAR;
+ if (mr == ATMEL_US_PAR_EVEN)
*parity = 'e';
- else if (mr == AT91_US_PAR_ODD)
+ else if (mr == ATMEL_US_PAR_ODD)
*parity = 'o';
- quot = UART_GET_BRGR(port);
- *baud = port->uartclk / (16 * (quot));
+ /*
+ * The serial core only rounds down when matching this to a
+ * supported baud rate. Make sure we don't end up slightly
+ * lower than one of those, as it would make us fall through
+ * to a much lower baud rate than we really want.
+ */
+ *baud = port->uartclk / (16 * (quot - 1));
}
-static int __init at91_console_setup(struct console *co, char *options)
+static int __init atmel_console_setup(struct console *co, char *options)
{
- struct uart_port *port = &at91_ports[co->index].uart;
+ struct uart_port *port = &atmel_ports[co->index].uart;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
- if (port->membase == 0) /* Port not initialized yet - delay setup */
+ if (port->membase == NULL) {
+ /* Port not initialized yet - delay setup */
return -ENODEV;
+ }
+
+ clk_enable(atmel_ports[co->index].clk);
- UART_PUT_IDR(port, -1); /* disable interrupts */
- UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX);
- UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN);
+ UART_PUT_IDR(port, -1);
+ UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+ UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
- at91_console_get_options(port, &baud, &parity, &bits);
+ atmel_console_get_options(port, &baud, &parity, &bits);
return uart_set_options(port, co, baud, parity, bits, flow);
}
-static struct uart_driver at91_uart;
+static struct uart_driver atmel_uart;
-static struct console at91_console = {
- .name = AT91_DEVICENAME,
- .write = at91_console_write,
+static struct console atmel_console = {
+ .name = ATMEL_DEVICENAME,
+ .write = atmel_console_write,
.device = uart_console_device,
- .setup = at91_console_setup,
+ .setup = atmel_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
- .data = &at91_uart,
+ .data = &atmel_uart,
};
-#define AT91_CONSOLE_DEVICE &at91_console
+#define ATMEL_CONSOLE_DEVICE (&atmel_console)
/*
* Early console initialization (before VM subsystem initialized).
*/
-static int __init at91_console_init(void)
+static int __init atmel_console_init(void)
{
- if (at91_default_console_device) {
- add_preferred_console(AT91_DEVICENAME, at91_default_console_device->id, NULL);
- at91_init_port(&(at91_ports[at91_default_console_device->id]), at91_default_console_device);
- register_console(&at91_console);
+ if (atmel_default_console_device) {
+ add_preferred_console(ATMEL_DEVICENAME,
+ atmel_default_console_device->id, NULL);
+ atmel_init_port(&atmel_ports[atmel_default_console_device->id],
+ atmel_default_console_device);
+ register_console(&atmel_console);
}
return 0;
}
-console_initcall(at91_console_init);
+
+console_initcall(atmel_console_init);
/*
* Late console initialization.
*/
-static int __init at91_late_console_init(void)
+static int __init atmel_late_console_init(void)
{
- if (at91_default_console_device && !(at91_console.flags & CON_ENABLED))
- register_console(&at91_console);
+ if (atmel_default_console_device
+ && !(atmel_console.flags & CON_ENABLED))
+ register_console(&atmel_console);
return 0;
}
-core_initcall(at91_late_console_init);
+
+core_initcall(atmel_late_console_init);
+
+static inline bool atmel_is_console_port(struct uart_port *port)
+{
+ return port->cons && port->cons->index == port->line;
+}
#else
-#define AT91_CONSOLE_DEVICE NULL
+#define ATMEL_CONSOLE_DEVICE NULL
+
+static inline bool atmel_is_console_port(struct uart_port *port)
+{
+ return false;
+}
#endif
-static struct uart_driver at91_uart = {
- .owner = THIS_MODULE,
- .driver_name = "at91_serial",
- .dev_name = AT91_DEVICENAME,
- .major = SERIAL_AT91_MAJOR,
- .minor = MINOR_START,
- .nr = AT91_NR_UART,
- .cons = AT91_CONSOLE_DEVICE,
+static struct uart_driver atmel_uart = {
+ .owner = THIS_MODULE,
+ .driver_name = "atmel_serial",
+ .dev_name = ATMEL_DEVICENAME,
+ .major = SERIAL_ATMEL_MAJOR,
+ .minor = MINOR_START,
+ .nr = ATMEL_MAX_UART,
+ .cons = ATMEL_CONSOLE_DEVICE,
};
#ifdef CONFIG_PM
-static int at91_serial_suspend(struct platform_device *pdev, pm_message_t state)
+static bool atmel_serial_clk_will_stop(void)
+{
+#ifdef CONFIG_ARCH_AT91
+ return at91_suspend_entering_slow_clock();
+#else
+ return false;
+#endif
+}
+
+static int atmel_serial_suspend(struct platform_device *pdev,
+ pm_message_t state)
{
struct uart_port *port = platform_get_drvdata(pdev);
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- if (device_may_wakeup(&pdev->dev) && !at91_suspend_entering_slow_clock())
- enable_irq_wake(port->irq);
- else {
- disable_irq_wake(port->irq);
- uart_suspend_port(&at91_uart, port);
- at91_port->suspended = 1;
+ if (atmel_is_console_port(port) && console_suspend_enabled) {
+ /* Drain the TX shifter */
+ while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY))
+ cpu_relax();
}
+ /* we can not wake up if we're running on slow clock */
+ atmel_port->may_wakeup = device_may_wakeup(&pdev->dev);
+ if (atmel_serial_clk_will_stop())
+ device_set_wakeup_enable(&pdev->dev, 0);
+
+ uart_suspend_port(&atmel_uart, port);
+
return 0;
}
-static int at91_serial_resume(struct platform_device *pdev)
+static int atmel_serial_resume(struct platform_device *pdev)
{
struct uart_port *port = platform_get_drvdata(pdev);
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- if (at91_port->suspended) {
- uart_resume_port(&at91_uart, port);
- at91_port->suspended = 0;
- }
+ uart_resume_port(&atmel_uart, port);
+ device_set_wakeup_enable(&pdev->dev, atmel_port->may_wakeup);
return 0;
}
#else
-#define at91_serial_suspend NULL
-#define at91_serial_resume NULL
+#define atmel_serial_suspend NULL
+#define atmel_serial_resume NULL
#endif
-static int __devinit at91_serial_probe(struct platform_device *pdev)
+static int __devinit atmel_serial_probe(struct platform_device *pdev)
{
- struct at91_uart_port *port;
+ struct atmel_uart_port *port;
+ void *data;
int ret;
- port = &at91_ports[pdev->id];
- at91_init_port(port, pdev);
+ BUILD_BUG_ON(ATMEL_SERIAL_RINGSIZE & (ATMEL_SERIAL_RINGSIZE - 1));
- ret = uart_add_one_port(&at91_uart, &port->uart);
- if (!ret) {
- device_init_wakeup(&pdev->dev, 1);
- platform_set_drvdata(pdev, port);
+ port = &atmel_ports[pdev->id];
+ port->backup_imr = 0;
+
+ atmel_init_port(port, pdev);
+
+ if (!atmel_use_dma_rx(&port->uart)) {
+ ret = -ENOMEM;
+ data = kmalloc(sizeof(struct atmel_uart_char)
+ * ATMEL_SERIAL_RINGSIZE, GFP_KERNEL);
+ if (!data)
+ goto err_alloc_ring;
+ port->rx_ring.buf = data;
+ }
+
+ ret = uart_add_one_port(&atmel_uart, &port->uart);
+ if (ret)
+ goto err_add_port;
+
+#ifdef CONFIG_SERIAL_ATMEL_CONSOLE
+ if (atmel_is_console_port(&port->uart)
+ && ATMEL_CONSOLE_DEVICE->flags & CON_ENABLED) {
+ /*
+ * The serial core enabled the clock for us, so undo
+ * the clk_enable() in atmel_console_setup()
+ */
+ clk_disable(port->clk);
+ }
+#endif
+
+ device_init_wakeup(&pdev->dev, 1);
+ platform_set_drvdata(pdev, port);
+
+ return 0;
+
+err_add_port:
+ kfree(port->rx_ring.buf);
+ port->rx_ring.buf = NULL;
+err_alloc_ring:
+ if (!atmel_is_console_port(&port->uart)) {
+ clk_put(port->clk);
+ port->clk = NULL;
}
return ret;
}
-static int __devexit at91_serial_remove(struct platform_device *pdev)
+static int __devexit atmel_serial_remove(struct platform_device *pdev)
{
struct uart_port *port = platform_get_drvdata(pdev);
- struct at91_uart_port *at91_port = (struct at91_uart_port *) port;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
int ret = 0;
- clk_disable(at91_port->clk);
- clk_put(at91_port->clk);
-
device_init_wakeup(&pdev->dev, 0);
platform_set_drvdata(pdev, NULL);
- if (port) {
- ret = uart_remove_one_port(&at91_uart, port);
- kfree(port);
- }
+ ret = uart_remove_one_port(&atmel_uart, port);
+
+ tasklet_kill(&atmel_port->tasklet);
+ kfree(atmel_port->rx_ring.buf);
+
+ /* "port" is allocated statically, so we shouldn't free it */
+
+ clk_put(atmel_port->clk);
return ret;
}
-static struct platform_driver at91_serial_driver = {
- .probe = at91_serial_probe,
- .remove = __devexit_p(at91_serial_remove),
- .suspend = at91_serial_suspend,
- .resume = at91_serial_resume,
+static struct platform_driver atmel_serial_driver = {
+ .probe = atmel_serial_probe,
+ .remove = __devexit_p(atmel_serial_remove),
+ .suspend = atmel_serial_suspend,
+ .resume = atmel_serial_resume,
.driver = {
.name = "atmel_usart",
.owner = THIS_MODULE,
},
};
-static int __init at91_serial_init(void)
+static int __init atmel_serial_init(void)
{
int ret;
- ret = uart_register_driver(&at91_uart);
+ ret = uart_register_driver(&atmel_uart);
if (ret)
return ret;
- ret = platform_driver_register(&at91_serial_driver);
+ ret = platform_driver_register(&atmel_serial_driver);
if (ret)
- uart_unregister_driver(&at91_uart);
+ uart_unregister_driver(&atmel_uart);
return ret;
}
-static void __exit at91_serial_exit(void)
+static void __exit atmel_serial_exit(void)
{
- platform_driver_unregister(&at91_serial_driver);
- uart_unregister_driver(&at91_uart);
+ platform_driver_unregister(&atmel_serial_driver);
+ uart_unregister_driver(&atmel_uart);
}
-module_init(at91_serial_init);
-module_exit(at91_serial_exit);
+module_init(atmel_serial_init);
+module_exit(atmel_serial_exit);
MODULE_AUTHOR("Rick Bronson");
-MODULE_DESCRIPTION("AT91 generic serial port driver");
+MODULE_DESCRIPTION("Atmel AT91 / AT32 serial port driver");
MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:atmel_usart");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff