Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
Blackfin Serial Driver: Use timer to poll CTS PIN instead of workqueue.
This allows other threads to run when the serial driver polls the CTS
PIN in a loop.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
authored by Sonic Zhang and committed by Bryan Wu f30ac0ce ec64b6c8
+18
-22
drivers/serial/bfin_5xx.c
+18
-22
drivers/serial/bfin_5xx.c
···
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#define DMA_RX_YCOUNT (PAGE_SIZE / DMA_RX_XCOUNT)
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#define DMA_RX_FLUSH_JIFFIES (HZ / 50)
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+
#define CTS_CHECK_JIFFIES (HZ / 50)
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#ifdef CONFIG_SERIAL_BFIN_DMA
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static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
···
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{
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struct circ_buf *xmit = &uart->port.info->xmit;
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-
if (uart->port.x_char) {
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UART_PUT_CHAR(uart, uart->port.x_char);
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uart->port.icount.tx++;
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uart->port.x_char = 0;
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-
}
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/*
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* Check the modem control lines before
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* transmitting anything.
···
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if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
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bfin_serial_stop_tx(&uart->port);
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return;
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+
}
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if (uart->port.x_char) {
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UART_PUT_CHAR(uart, uart->port.x_char);
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uart->port.icount.tx++;
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uart->port.x_char = 0;
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}
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while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
···
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}
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#endif
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-
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
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static void bfin_serial_do_work(struct work_struct *work)
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-
{
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struct bfin_serial_port *uart = container_of(work, struct bfin_serial_port, cts_workqueue);
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bfin_serial_mctrl_check(uart);
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}
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#endif
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-
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#ifdef CONFIG_SERIAL_BFIN_DMA
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static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
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{
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struct circ_buf *xmit = &uart->port.info->xmit;
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uart->tx_done = 0;
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+
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/*
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* Check the modem control lines before
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* transmitting anything.
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*/
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bfin_serial_mctrl_check(uart);
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if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
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uart->tx_count = 0;
···
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uart->port.icount.tx++;
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uart->port.x_char = 0;
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}
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-
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/*
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* Check the modem control lines before
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* transmitting anything.
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-
*/
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bfin_serial_mctrl_check(uart);
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uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
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if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
···
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uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
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if (!(status & TIOCM_CTS)) {
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tty->hw_stopped = 1;
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-
schedule_work(&uart->cts_workqueue);
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+
uart->cts_timer.data = (unsigned long)(uart);
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+
uart->cts_timer.function = (void *)bfin_serial_mctrl_check;
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uart->cts_timer.expires = jiffies + CTS_CHECK_JIFFIES;
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add_timer(&(uart->cts_timer));
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} else {
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tty->hw_stopped = 0;
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}
···
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init_timer(&(bfin_serial_ports[i].rx_dma_timer));
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#endif
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#ifdef CONFIG_SERIAL_BFIN_CTSRTS
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-
INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
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+
init_timer(&(bfin_serial_ports[i].cts_timer));
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bfin_serial_ports[i].cts_pin =
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bfin_serial_resource[i].uart_cts_pin;
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bfin_serial_ports[i].rts_pin =
+1
-1
include/asm-blackfin/mach-bf527/bfin_serial_5xx.h
+1
-1
include/asm-blackfin/mach-bf527/bfin_serial_5xx.h
+1
-1
include/asm-blackfin/mach-bf533/bfin_serial_5xx.h
+1
-1
include/asm-blackfin/mach-bf533/bfin_serial_5xx.h
+1
-1
include/asm-blackfin/mach-bf537/bfin_serial_5xx.h
+1
-1
include/asm-blackfin/mach-bf537/bfin_serial_5xx.h
+1
-1
include/asm-blackfin/mach-bf548/bfin_serial_5xx.h
+1
-1
include/asm-blackfin/mach-bf548/bfin_serial_5xx.h