[RFC 21/24] SERIAL: omap: use tx buffer allocation API
From: Russell King <hidden>
Date: 2012-10-06 12:46:07
Also in:
linux-arm-kernel, linux-omap
Subsystem:
the rest, tty layer and serial drivers · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
Rather than working around serial_core, use the newly provided buffer allocation API to allow a saner method to manage this buffer. Signed-off-by: Russell King <redacted> --- drivers/tty/serial/omap-serial.c | 38 +++++++++++++++++++++++++++++--------- 1 files changed, 29 insertions(+), 9 deletions(-)
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index b497187..6054fc8 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c@@ -604,11 +604,6 @@ static int serial_omap_startup(struct uart_port *port) up->msr_saved_flags = 0; if (up->use_dma) { - free_page((unsigned long)up->port.state->xmit.buf); - up->port.state->xmit.buf = dma_alloc_coherent(NULL, - UART_XMIT_SIZE, - (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys), - 0); init_timer(&(up->uart_dma.rx_timer)); up->uart_dma.rx_timer.function = serial_omap_rxdma_poll; up->uart_dma.rx_timer.data = up->port.line;
@@ -665,10 +660,6 @@ static void serial_omap_shutdown(struct uart_port *port) if (serial_in(up, UART_LSR) & UART_LSR_DR) (void) serial_in(up, UART_RX); if (up->use_dma) { - dma_free_coherent(up->port.dev, - UART_XMIT_SIZE, up->port.state->xmit.buf, - up->uart_dma.tx_buf_dma_phys); - up->port.state->xmit.buf = NULL; serial_omap_stop_rx(port); dma_free_coherent(up->port.dev, up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
@@ -680,6 +671,33 @@ static void serial_omap_shutdown(struct uart_port *port) free_irq(up->port.irq, up); } +static int serial_omap_alloc_xmit(struct uart_port *port, struct circ_buf *xmit) +{ + struct uart_omap_port *up = (struct uart_omap_port *)port; + + if (up->use_dma) { + xmit->buf = dma_alloc_coherent(NULL, UART_XMIT_SIZE, + &up->uart_dma.tx_buf_dma_phys, 0); + } else { + unsigned long page = get_zeroed_page(GFP_KERNEL); + xmit->buf = (unsigned char *)page; + } + + return xmit->buf ? 0 : -ENOMEM; +} + +static void serial_omap_free_xmit(struct uart_port *port, struct circ_buf *xmit) +{ + struct uart_omap_port *up = (struct uart_omap_port *)port; + + if (up->use_dma) { + dma_free_coherent(NULL, UART_XMIT_SIZE, + xmit->buf, up->uart_dma.tx_buf_dma_phys); + } else { + free_page((unsigned long)xmit->buf); + } +} + static void serial_omap_uart_qos_work(struct work_struct *work) { struct uart_omap_port *up = container_of(work, struct uart_omap_port,
@@ -1193,6 +1211,8 @@ static struct uart_ops serial_omap_pops = { .break_ctl = serial_omap_break_ctl, .startup = serial_omap_startup, .shutdown = serial_omap_shutdown, + .alloc_xmit = serial_omap_alloc_xmit, + .free_xmit = serial_omap_free_xmit, .set_termios = serial_omap_set_termios, .pm = serial_omap_pm, .type = serial_omap_type,
--
1.7.4.4