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path: root/drivers/serial/bfin_sport_uart.c
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Diffstat (limited to 'drivers/serial/bfin_sport_uart.c')
-rw-r--r--drivers/serial/bfin_sport_uart.c618
1 files changed, 0 insertions, 618 deletions
diff --git a/drivers/serial/bfin_sport_uart.c b/drivers/serial/bfin_sport_uart.c
deleted file mode 100644
index 34b4ae0fe76..00000000000
--- a/drivers/serial/bfin_sport_uart.c
+++ /dev/null
@@ -1,618 +0,0 @@
-/*
- * File: linux/drivers/serial/bfin_sport_uart.c
- *
- * Based on: drivers/serial/bfin_5xx.c by Aubrey Li.
- * Author: Roy Huang <roy.huang@analog.com>
- *
- * Created: Nov 22, 2006
- * Copyright: (c) 2006-2007 Analog Devices Inc.
- * Description: this driver enable SPORTs on Blackfin emulate UART.
- *
- * 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
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see the file COPYING, or write
- * to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/*
- * This driver and the hardware supported are in term of EE-191 of ADI.
- * http://www.analog.com/UploadedFiles/Application_Notes/399447663EE191.pdf
- * This application note describe how to implement a UART on a Sharc DSP,
- * but this driver is implemented on Blackfin Processor.
- */
-
-/* After reset, there is a prelude of low level pulse when transmit data first
- * time. No addtional pulse in following transmit.
- * According to document:
- * The SPORTs are ready to start transmitting or receiving data no later than
- * three serial clock cycles after they are enabled in the SPORTx_TCR1 or
- * SPORTx_RCR1 register. No serial clock cycles are lost from this point on.
- * The first internal frame sync will occur one frame sync delay after the
- * SPORTs are ready. External frame syncs can occur as soon as the SPORT is
- * ready.
- */
-
-/* Thanks to Axel Alatalo <axel@rubico.se> for fixing sport rx bug. Sometimes
- * sport receives data incorrectly. The following is Axel's words.
- * As EE-191, sport rx samples 3 times of the UART baudrate and takes the
- * middle smaple of every 3 samples as the data bit. For a 8-N-1 UART setting,
- * 30 samples will be required for a byte. If transmitter sends a 1/3 bit short
- * byte due to buadrate drift, then the 30th sample of a byte, this sample is
- * also the third sample of the stop bit, will happens on the immediately
- * following start bit which will be thrown away and missed. Thus since parts
- * of the startbit will be missed and the receiver will begin to drift, the
- * effect accumulates over time until synchronization is lost.
- * If only require 2 samples of the stopbit (by sampling in total 29 samples),
- * then a to short byte as in the case above will be tolerated. Then the 1/3
- * early startbit will trigger a framesync since the last read is complete
- * after only 2/3 stopbit and framesync is active during the last 1/3 looking
- * for a possible early startbit. */
-
-//#define DEBUG
-
-#include <linux/module.h>
-#include <linux/ioport.h>
-#include <linux/init.h>
-#include <linux/console.h>
-#include <linux/sysrq.h>
-#include <linux/platform_device.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-#include <linux/serial_core.h>
-
-#include <asm/delay.h>
-#include <asm/portmux.h>
-
-#include "bfin_sport_uart.h"
-
-unsigned short bfin_uart_pin_req_sport0[] =
- {P_SPORT0_TFS, P_SPORT0_DTPRI, P_SPORT0_TSCLK, P_SPORT0_RFS, \
- P_SPORT0_DRPRI, P_SPORT0_RSCLK, P_SPORT0_DRSEC, P_SPORT0_DTSEC, 0};
-
-unsigned short bfin_uart_pin_req_sport1[] =
- {P_SPORT1_TFS, P_SPORT1_DTPRI, P_SPORT1_TSCLK, P_SPORT1_RFS, \
- P_SPORT1_DRPRI, P_SPORT1_RSCLK, P_SPORT1_DRSEC, P_SPORT1_DTSEC, 0};
-
-#define DRV_NAME "bfin-sport-uart"
-
-struct sport_uart_port {
- struct uart_port port;
- char *name;
-
- int tx_irq;
- int rx_irq;
- int err_irq;
-};
-
-static void sport_uart_tx_chars(struct sport_uart_port *up);
-static void sport_stop_tx(struct uart_port *port);
-
-static inline void tx_one_byte(struct sport_uart_port *up, unsigned int value)
-{
- pr_debug("%s value:%x\n", __func__, value);
- /* Place a Start and Stop bit */
- __asm__ __volatile__ (
- "R2 = b#01111111100;"
- "R3 = b#10000000001;"
- "%0 <<= 2;"
- "%0 = %0 & R2;"
- "%0 = %0 | R3;"
- : "=d"(value)
- : "d"(value)
- : "ASTAT", "R2", "R3"
- );
- pr_debug("%s value:%x\n", __func__, value);
-
- SPORT_PUT_TX(up, value);
-}
-
-static inline unsigned int rx_one_byte(struct sport_uart_port *up)
-{
- unsigned int value, extract;
- u32 tmp_mask1, tmp_mask2, tmp_shift, tmp;
-
- value = SPORT_GET_RX32(up);
- pr_debug("%s value:%x\n", __func__, value);
-
- /* Extract 8 bits data */
- __asm__ __volatile__ (
- "%[extr] = 0;"
- "%[mask1] = 0x1801(Z);"
- "%[mask2] = 0x0300(Z);"
- "%[shift] = 0;"
- "LSETUP(.Lloop_s, .Lloop_e) LC0 = %[lc];"
- ".Lloop_s:"
- "%[tmp] = extract(%[val], %[mask1].L)(Z);"
- "%[tmp] <<= %[shift];"
- "%[extr] = %[extr] | %[tmp];"
- "%[mask1] = %[mask1] - %[mask2];"
- ".Lloop_e:"
- "%[shift] += 1;"
- : [val]"=d"(value), [extr]"=d"(extract), [shift]"=d"(tmp_shift), [tmp]"=d"(tmp),
- [mask1]"=d"(tmp_mask1), [mask2]"=d"(tmp_mask2)
- : "d"(value), [lc]"a"(8)
- : "ASTAT", "LB0", "LC0", "LT0"
- );
-
- pr_debug(" extract:%x\n", extract);
- return extract;
-}
-
-static int sport_uart_setup(struct sport_uart_port *up, int sclk, int baud_rate)
-{
- int tclkdiv, tfsdiv, rclkdiv;
-
- /* Set TCR1 and TCR2 */
- SPORT_PUT_TCR1(up, (LATFS | ITFS | TFSR | TLSBIT | ITCLK));
- SPORT_PUT_TCR2(up, 10);
- pr_debug("%s TCR1:%x, TCR2:%x\n", __func__, SPORT_GET_TCR1(up), SPORT_GET_TCR2(up));
-
- /* Set RCR1 and RCR2 */
- SPORT_PUT_RCR1(up, (RCKFE | LARFS | LRFS | RFSR | IRCLK));
- SPORT_PUT_RCR2(up, 28);
- pr_debug("%s RCR1:%x, RCR2:%x\n", __func__, SPORT_GET_RCR1(up), SPORT_GET_RCR2(up));
-
- tclkdiv = sclk/(2 * baud_rate) - 1;
- tfsdiv = 12;
- rclkdiv = sclk/(2 * baud_rate * 3) - 1;
- SPORT_PUT_TCLKDIV(up, tclkdiv);
- SPORT_PUT_TFSDIV(up, tfsdiv);
- SPORT_PUT_RCLKDIV(up, rclkdiv);
- SSYNC();
- pr_debug("%s sclk:%d, baud_rate:%d, tclkdiv:%d, tfsdiv:%d, rclkdiv:%d\n",
- __func__, sclk, baud_rate, tclkdiv, tfsdiv, rclkdiv);
-
- return 0;
-}
-
-static irqreturn_t sport_uart_rx_irq(int irq, void *dev_id)
-{
- struct sport_uart_port *up = dev_id;
- struct tty_struct *tty = up->port.info->port.tty;
- unsigned int ch;
-
- do {
- ch = rx_one_byte(up);
- up->port.icount.rx++;
-
- if (uart_handle_sysrq_char(&up->port, ch))
- ;
- else
- tty_insert_flip_char(tty, ch, TTY_NORMAL);
- } while (SPORT_GET_STAT(up) & RXNE);
- tty_flip_buffer_push(tty);
-
- return IRQ_HANDLED;
-}
-
-static irqreturn_t sport_uart_tx_irq(int irq, void *dev_id)
-{
- sport_uart_tx_chars(dev_id);
-
- return IRQ_HANDLED;
-}
-
-static irqreturn_t sport_uart_err_irq(int irq, void *dev_id)
-{
- struct sport_uart_port *up = dev_id;
- struct tty_struct *tty = up->port.info->port.tty;
- unsigned int stat = SPORT_GET_STAT(up);
-
- /* Overflow in RX FIFO */
- if (stat & ROVF) {
- up->port.icount.overrun++;
- tty_insert_flip_char(tty, 0, TTY_OVERRUN);
- SPORT_PUT_STAT(up, ROVF); /* Clear ROVF bit */
- }
- /* These should not happen */
- if (stat & (TOVF | TUVF | RUVF)) {
- printk(KERN_ERR "SPORT Error:%s %s %s\n",
- (stat & TOVF)?"TX overflow":"",
- (stat & TUVF)?"TX underflow":"",
- (stat & RUVF)?"RX underflow":"");
- SPORT_PUT_TCR1(up, SPORT_GET_TCR1(up) & ~TSPEN);
- SPORT_PUT_RCR1(up, SPORT_GET_RCR1(up) & ~RSPEN);
- }
- SSYNC();
-
- return IRQ_HANDLED;
-}
-
-/* Reqeust IRQ, Setup clock */
-static int sport_startup(struct uart_port *port)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
- char buffer[20];
- int retval;
-
- pr_debug("%s enter\n", __func__);
- memset(buffer, 20, '\0');
- snprintf(buffer, 20, "%s rx", up->name);
- retval = request_irq(up->rx_irq, sport_uart_rx_irq, IRQF_SAMPLE_RANDOM, buffer, up);
- if (retval) {
- printk(KERN_ERR "Unable to request interrupt %s\n", buffer);
- return retval;
- }
-
- snprintf(buffer, 20, "%s tx", up->name);
- retval = request_irq(up->tx_irq, sport_uart_tx_irq, IRQF_SAMPLE_RANDOM, buffer, up);
- if (retval) {
- printk(KERN_ERR "Unable to request interrupt %s\n", buffer);
- goto fail1;
- }
-
- snprintf(buffer, 20, "%s err", up->name);
- retval = request_irq(up->err_irq, sport_uart_err_irq, IRQF_SAMPLE_RANDOM, buffer, up);
- if (retval) {
- printk(KERN_ERR "Unable to request interrupt %s\n", buffer);
- goto fail2;
- }
-
- if (port->line) {
- if (peripheral_request_list(bfin_uart_pin_req_sport1, DRV_NAME))
- goto fail3;
- } else {
- if (peripheral_request_list(bfin_uart_pin_req_sport0, DRV_NAME))
- goto fail3;
- }
-
- sport_uart_setup(up, get_sclk(), port->uartclk);
-
- /* Enable receive interrupt */
- SPORT_PUT_RCR1(up, (SPORT_GET_RCR1(up) | RSPEN));
- SSYNC();
-
- return 0;
-
-
-fail3:
- printk(KERN_ERR DRV_NAME
- ": Requesting Peripherals failed\n");
-
- free_irq(up->err_irq, up);
-fail2:
- free_irq(up->tx_irq, up);
-fail1:
- free_irq(up->rx_irq, up);
-
- return retval;
-
-}
-
-static void sport_uart_tx_chars(struct sport_uart_port *up)
-{
- struct circ_buf *xmit = &up->port.info->xmit;
-
- if (SPORT_GET_STAT(up) & TXF)
- return;
-
- if (up->port.x_char) {
- tx_one_byte(up, up->port.x_char);
- up->port.icount.tx++;
- up->port.x_char = 0;
- return;
- }
-
- if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
- sport_stop_tx(&up->port);
- return;
- }
-
- while(!(SPORT_GET_STAT(up) & TXF) && !uart_circ_empty(xmit)) {
- tx_one_byte(up, xmit->buf[xmit->tail]);
- xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE -1);
- up->port.icount.tx++;
- }
-
- if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
- uart_write_wakeup(&up->port);
-}
-
-static unsigned int sport_tx_empty(struct uart_port *port)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
- unsigned int stat;
-
- stat = SPORT_GET_STAT(up);
- pr_debug("%s stat:%04x\n", __func__, stat);
- if (stat & TXHRE) {
- return TIOCSER_TEMT;
- } else
- return 0;
-}
-
-static unsigned int sport_get_mctrl(struct uart_port *port)
-{
- pr_debug("%s enter\n", __func__);
- return (TIOCM_CTS | TIOCM_CD | TIOCM_DSR);
-}
-
-static void sport_set_mctrl(struct uart_port *port, unsigned int mctrl)
-{
- pr_debug("%s enter\n", __func__);
-}
-
-static void sport_stop_tx(struct uart_port *port)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
- unsigned int stat;
-
- pr_debug("%s enter\n", __func__);
-
- stat = SPORT_GET_STAT(up);
- while(!(stat & TXHRE)) {
- udelay(1);
- stat = SPORT_GET_STAT(up);
- }
- /* Although the hold register is empty, last byte is still in shift
- * register and not sent out yet. If baud rate is lower than default,
- * delay should be longer. For example, if the baud rate is 9600,
- * the delay must be at least 2ms by experience */
- udelay(500);
-
- SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) & ~TSPEN));
- SSYNC();
-
- return;
-}
-
-static void sport_start_tx(struct uart_port *port)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
-
- pr_debug("%s enter\n", __func__);
- /* Write data into SPORT FIFO before enable SPROT to transmit */
- sport_uart_tx_chars(up);
-
- /* Enable transmit, then an interrupt will generated */
- SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) | TSPEN));
- SSYNC();
- pr_debug("%s exit\n", __func__);
-}
-
-static void sport_stop_rx(struct uart_port *port)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
-
- pr_debug("%s enter\n", __func__);
- /* Disable sport to stop rx */
- SPORT_PUT_RCR1(up, (SPORT_GET_RCR1(up) & ~RSPEN));
- SSYNC();
-}
-
-static void sport_enable_ms(struct uart_port *port)
-{
- pr_debug("%s enter\n", __func__);
-}
-
-static void sport_break_ctl(struct uart_port *port, int break_state)
-{
- pr_debug("%s enter\n", __func__);
-}
-
-static void sport_shutdown(struct uart_port *port)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
-
- pr_debug("%s enter\n", __func__);
-
- /* Disable sport */
- SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) & ~TSPEN));
- SPORT_PUT_RCR1(up, (SPORT_GET_RCR1(up) & ~RSPEN));
- SSYNC();
-
- if (port->line) {
- peripheral_free_list(bfin_uart_pin_req_sport1);
- } else {
- peripheral_free_list(bfin_uart_pin_req_sport0);
- }
-
- free_irq(up->rx_irq, up);
- free_irq(up->tx_irq, up);
- free_irq(up->err_irq, up);
-}
-
-static void sport_set_termios(struct uart_port *port,
- struct ktermios *termios, struct ktermios *old)
-{
- pr_debug("%s enter, c_cflag:%08x\n", __func__, termios->c_cflag);
- uart_update_timeout(port, CS8 ,port->uartclk);
-}
-
-static const char *sport_type(struct uart_port *port)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
-
- pr_debug("%s enter\n", __func__);
- return up->name;
-}
-
-static void sport_release_port(struct uart_port *port)
-{
- pr_debug("%s enter\n", __func__);
-}
-
-static int sport_request_port(struct uart_port *port)
-{
- pr_debug("%s enter\n", __func__);
- return 0;
-}
-
-static void sport_config_port(struct uart_port *port, int flags)
-{
- struct sport_uart_port *up = (struct sport_uart_port *)port;
-
- pr_debug("%s enter\n", __func__);
- up->port.type = PORT_BFIN_SPORT;
-}
-
-static int sport_verify_port(struct uart_port *port, struct serial_struct *ser)
-{
- pr_debug("%s enter\n", __func__);
- return 0;
-}
-
-struct uart_ops sport_uart_ops = {
- .tx_empty = sport_tx_empty,
- .set_mctrl = sport_set_mctrl,
- .get_mctrl = sport_get_mctrl,
- .stop_tx = sport_stop_tx,
- .start_tx = sport_start_tx,
- .stop_rx = sport_stop_rx,
- .enable_ms = sport_enable_ms,
- .break_ctl = sport_break_ctl,
- .startup = sport_startup,
- .shutdown = sport_shutdown,
- .set_termios = sport_set_termios,
- .type = sport_type,
- .release_port = sport_release_port,
- .request_port = sport_request_port,
- .config_port = sport_config_port,
- .verify_port = sport_verify_port,
-};
-
-static struct sport_uart_port sport_uart_ports[] = {
- { /* SPORT 0 */
- .name = "SPORT0",
- .tx_irq = IRQ_SPORT0_TX,
- .rx_irq = IRQ_SPORT0_RX,
- .err_irq= IRQ_SPORT0_ERROR,
- .port = {
- .type = PORT_BFIN_SPORT,
- .iotype = UPIO_MEM,
- .membase = (void __iomem *)SPORT0_TCR1,
- .mapbase = SPORT0_TCR1,
- .irq = IRQ_SPORT0_RX,
- .uartclk = CONFIG_SPORT_BAUD_RATE,
- .fifosize = 8,
- .ops = &sport_uart_ops,
- .line = 0,
- },
- }, { /* SPORT 1 */
- .name = "SPORT1",
- .tx_irq = IRQ_SPORT1_TX,
- .rx_irq = IRQ_SPORT1_RX,
- .err_irq= IRQ_SPORT1_ERROR,
- .port = {
- .type = PORT_BFIN_SPORT,
- .iotype = UPIO_MEM,
- .membase = (void __iomem *)SPORT1_TCR1,
- .mapbase = SPORT1_TCR1,
- .irq = IRQ_SPORT1_RX,
- .uartclk = CONFIG_SPORT_BAUD_RATE,
- .fifosize = 8,
- .ops = &sport_uart_ops,
- .line = 1,
- },
- }
-};
-
-static struct uart_driver sport_uart_reg = {
- .owner = THIS_MODULE,
- .driver_name = "SPORT-UART",
- .dev_name = "ttySS",
- .major = 204,
- .minor = 84,
- .nr = ARRAY_SIZE(sport_uart_ports),
- .cons = NULL,
-};
-
-static int sport_uart_suspend(struct platform_device *dev, pm_message_t state)
-{
- struct sport_uart_port *sport = platform_get_drvdata(dev);
-
- pr_debug("%s enter\n", __func__);
- if (sport)
- uart_suspend_port(&sport_uart_reg, &sport->port);
-
- return 0;
-}
-
-static int sport_uart_resume(struct platform_device *dev)
-{
- struct sport_uart_port *sport = platform_get_drvdata(dev);
-
- pr_debug("%s enter\n", __func__);
- if (sport)
- uart_resume_port(&sport_uart_reg, &sport->port);
-
- return 0;
-}
-
-static int sport_uart_probe(struct platform_device *dev)
-{
- pr_debug("%s enter\n", __func__);
- sport_uart_ports[dev->id].port.dev = &dev->dev;
- uart_add_one_port(&sport_uart_reg, &sport_uart_ports[dev->id].port);
- platform_set_drvdata(dev, &sport_uart_ports[dev->id]);
-
- return 0;
-}
-
-static int sport_uart_remove(struct platform_device *dev)
-{
- struct sport_uart_port *sport = platform_get_drvdata(dev);
-
- pr_debug("%s enter\n", __func__);
- platform_set_drvdata(dev, NULL);
-
- if (sport)
- uart_remove_one_port(&sport_uart_reg, &sport->port);
-
- return 0;
-}
-
-static struct platform_driver sport_uart_driver = {
- .probe = sport_uart_probe,
- .remove = sport_uart_remove,
- .suspend = sport_uart_suspend,
- .resume = sport_uart_resume,
- .driver = {
- .name = DRV_NAME,
- },
-};
-
-static int __init sport_uart_init(void)
-{
- int ret;
-
- pr_debug("%s enter\n", __func__);
- ret = uart_register_driver(&sport_uart_reg);
- if (ret != 0) {
- printk(KERN_ERR "Failed to register %s:%d\n",
- sport_uart_reg.driver_name, ret);
- return ret;
- }
-
- ret = platform_driver_register(&sport_uart_driver);
- if (ret != 0) {
- printk(KERN_ERR "Failed to register sport uart driver:%d\n", ret);
- uart_unregister_driver(&sport_uart_reg);
- }
-
-
- pr_debug("%s exit\n", __func__);
- return ret;
-}
-
-static void __exit sport_uart_exit(void)
-{
- pr_debug("%s enter\n", __func__);
- platform_driver_unregister(&sport_uart_driver);
- uart_unregister_driver(&sport_uart_reg);
-}
-
-module_init(sport_uart_init);
-module_exit(sport_uart_exit);
-
-MODULE_LICENSE("GPL");
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