sdio_uart: Use kfifo instead of the messy circ stuff

Revised patch to use the new kfifo API. This replaces the one that was dropped
from -next due to collisions with the kfifo API changes.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Cox 2010-02-08 10:08:39 +00:00 committed by Greg Kroah-Hartman
parent 6a2c7eabfd
commit 8b197a5ce7
1 changed files with 30 additions and 63 deletions

View File

@ -37,6 +37,7 @@
#include <linux/gfp.h> #include <linux/gfp.h>
#include <linux/tty.h> #include <linux/tty.h>
#include <linux/tty_flip.h> #include <linux/tty_flip.h>
#include <linux/kfifo.h>
#include <linux/mmc/core.h> #include <linux/mmc/core.h>
#include <linux/mmc/card.h> #include <linux/mmc/card.h>
@ -47,19 +48,9 @@
#define UART_NR 8 /* Number of UARTs this driver can handle */ #define UART_NR 8 /* Number of UARTs this driver can handle */
#define UART_XMIT_SIZE PAGE_SIZE #define FIFO_SIZE PAGE_SIZE
#define WAKEUP_CHARS 256 #define WAKEUP_CHARS 256
#define circ_empty(circ) ((circ)->head == (circ)->tail)
#define circ_clear(circ) ((circ)->head = (circ)->tail = 0)
#define circ_chars_pending(circ) \
(CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
#define circ_chars_free(circ) \
(CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
struct uart_icount { struct uart_icount {
__u32 cts; __u32 cts;
__u32 dsr; __u32 dsr;
@ -82,7 +73,7 @@ struct sdio_uart_port {
struct mutex func_lock; struct mutex func_lock;
struct task_struct *in_sdio_uart_irq; struct task_struct *in_sdio_uart_irq;
unsigned int regs_offset; unsigned int regs_offset;
struct circ_buf xmit; struct kfifo xmit_fifo;
spinlock_t write_lock; spinlock_t write_lock;
struct uart_icount icount; struct uart_icount icount;
unsigned int uartclk; unsigned int uartclk;
@ -105,6 +96,8 @@ static int sdio_uart_add_port(struct sdio_uart_port *port)
kref_init(&port->kref); kref_init(&port->kref);
mutex_init(&port->func_lock); mutex_init(&port->func_lock);
spin_lock_init(&port->write_lock); spin_lock_init(&port->write_lock);
if (kfifo_alloc(&port->xmit_fifo, FIFO_SIZE, GFP_KERNEL))
return -ENOMEM;
spin_lock(&sdio_uart_table_lock); spin_lock(&sdio_uart_table_lock);
for (index = 0; index < UART_NR; index++) { for (index = 0; index < UART_NR; index++) {
@ -140,6 +133,7 @@ static void sdio_uart_port_destroy(struct kref *kref)
{ {
struct sdio_uart_port *port = struct sdio_uart_port *port =
container_of(kref, struct sdio_uart_port, kref); container_of(kref, struct sdio_uart_port, kref);
kfifo_free(&port->xmit_fifo);
kfree(port); kfree(port);
} }
@ -456,9 +450,11 @@ static void sdio_uart_receive_chars(struct sdio_uart_port *port,
static void sdio_uart_transmit_chars(struct sdio_uart_port *port) static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
{ {
struct circ_buf *xmit = &port->xmit; struct kfifo *xmit = &port->xmit_fifo;
int count; int count;
struct tty_struct *tty; struct tty_struct *tty;
u8 iobuf[16];
int len;
if (port->x_char) { if (port->x_char) {
sdio_out(port, UART_TX, port->x_char); sdio_out(port, UART_TX, port->x_char);
@ -469,27 +465,25 @@ static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
tty = tty_port_tty_get(&port->port); tty = tty_port_tty_get(&port->port);
if (tty == NULL || circ_empty(xmit) || if (tty == NULL || !kfifo_len(xmit) ||
tty->stopped || tty->hw_stopped) { tty->stopped || tty->hw_stopped) {
sdio_uart_stop_tx(port); sdio_uart_stop_tx(port);
tty_kref_put(tty); tty_kref_put(tty);
return; return;
} }
count = 16; len = kfifo_out_locked(xmit, iobuf, 16, &port->write_lock);
do { for (count = 0; count < len; count++) {
sdio_out(port, UART_TX, xmit->buf[xmit->tail]); sdio_out(port, UART_TX, iobuf[count]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++; port->icount.tx++;
if (circ_empty(xmit)) }
break;
} while (--count > 0);
if (circ_chars_pending(xmit) < WAKEUP_CHARS) len = kfifo_len(xmit);
if (len < WAKEUP_CHARS) {
tty_wakeup(tty); tty_wakeup(tty);
if (len == 0)
if (circ_empty(xmit)) sdio_uart_stop_tx(port);
sdio_uart_stop_tx(port); }
tty_kref_put(tty); tty_kref_put(tty);
} }
@ -632,7 +626,6 @@ static int sdio_uart_activate(struct tty_port *tport, struct tty_struct *tty)
{ {
struct sdio_uart_port *port = struct sdio_uart_port *port =
container_of(tport, struct sdio_uart_port, port); container_of(tport, struct sdio_uart_port, port);
unsigned long page;
int ret; int ret;
/* /*
@ -641,22 +634,17 @@ static int sdio_uart_activate(struct tty_port *tport, struct tty_struct *tty)
*/ */
set_bit(TTY_IO_ERROR, &tty->flags); set_bit(TTY_IO_ERROR, &tty->flags);
/* Initialise and allocate the transmit buffer. */ kfifo_reset(&port->xmit_fifo);
page = __get_free_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
port->xmit.buf = (unsigned char *)page;
circ_clear(&port->xmit);
ret = sdio_uart_claim_func(port); ret = sdio_uart_claim_func(port);
if (ret) if (ret)
goto err1; return ret;
ret = sdio_enable_func(port->func); ret = sdio_enable_func(port->func);
if (ret) if (ret)
goto err2; goto err1;
ret = sdio_claim_irq(port->func, sdio_uart_irq); ret = sdio_claim_irq(port->func, sdio_uart_irq);
if (ret) if (ret)
goto err3; goto err2;
/* /*
* Clear the FIFO buffers and disable them. * Clear the FIFO buffers and disable them.
@ -700,12 +688,10 @@ static int sdio_uart_activate(struct tty_port *tport, struct tty_struct *tty)
sdio_uart_release_func(port); sdio_uart_release_func(port);
return 0; return 0;
err3:
sdio_disable_func(port->func);
err2: err2:
sdio_uart_release_func(port); sdio_disable_func(port->func);
err1: err1:
free_page((unsigned long)port->xmit.buf); sdio_uart_release_func(port);
return ret; return ret;
} }
@ -727,7 +713,7 @@ static void sdio_uart_shutdown(struct tty_port *tport)
ret = sdio_uart_claim_func(port); ret = sdio_uart_claim_func(port);
if (ret) if (ret)
goto skip; return;
sdio_uart_stop_rx(port); sdio_uart_stop_rx(port);
@ -749,10 +735,6 @@ static void sdio_uart_shutdown(struct tty_port *tport)
sdio_disable_func(port->func); sdio_disable_func(port->func);
sdio_uart_release_func(port); sdio_uart_release_func(port);
skip:
/* Free the transmit buffer page. */
free_page((unsigned long)port->xmit.buf);
} }
/** /**
@ -822,27 +804,12 @@ static int sdio_uart_write(struct tty_struct *tty, const unsigned char *buf,
int count) int count)
{ {
struct sdio_uart_port *port = tty->driver_data; struct sdio_uart_port *port = tty->driver_data;
struct circ_buf *circ = &port->xmit; int ret;
int c, ret = 0;
if (!port->func) if (!port->func)
return -ENODEV; return -ENODEV;
spin_lock(&port->write_lock); ret = kfifo_in_locked(&port->xmit_fifo, buf, count, &port->write_lock);
while (1) {
c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE);
if (count < c)
c = count;
if (c <= 0)
break;
memcpy(circ->buf + circ->head, buf, c);
circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1);
buf += c;
count -= c;
ret += c;
}
spin_unlock(&port->write_lock);
if (!(port->ier & UART_IER_THRI)) { if (!(port->ier & UART_IER_THRI)) {
int err = sdio_uart_claim_func(port); int err = sdio_uart_claim_func(port);
if (!err) { if (!err) {
@ -859,13 +826,13 @@ static int sdio_uart_write(struct tty_struct *tty, const unsigned char *buf,
static int sdio_uart_write_room(struct tty_struct *tty) static int sdio_uart_write_room(struct tty_struct *tty)
{ {
struct sdio_uart_port *port = tty->driver_data; struct sdio_uart_port *port = tty->driver_data;
return port ? circ_chars_free(&port->xmit) : 0; return FIFO_SIZE - kfifo_len(&port->xmit_fifo);
} }
static int sdio_uart_chars_in_buffer(struct tty_struct *tty) static int sdio_uart_chars_in_buffer(struct tty_struct *tty)
{ {
struct sdio_uart_port *port = tty->driver_data; struct sdio_uart_port *port = tty->driver_data;
return port ? circ_chars_pending(&port->xmit) : 0; return kfifo_len(&port->xmit_fifo);
} }
static void sdio_uart_send_xchar(struct tty_struct *tty, char ch) static void sdio_uart_send_xchar(struct tty_struct *tty, char ch)