diff options
Diffstat (limited to 'recipes/linux/linux-2.6.18/usart-make-rx-timeout-baudrate-independent.patch')
-rw-r--r-- | recipes/linux/linux-2.6.18/usart-make-rx-timeout-baudrate-independent.patch | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/recipes/linux/linux-2.6.18/usart-make-rx-timeout-baudrate-independent.patch b/recipes/linux/linux-2.6.18/usart-make-rx-timeout-baudrate-independent.patch new file mode 100644 index 0000000000..9da06670ea --- /dev/null +++ b/recipes/linux/linux-2.6.18/usart-make-rx-timeout-baudrate-independent.patch @@ -0,0 +1,83 @@ +--- + drivers/serial/atmel_usart.c | 33 ++++++++++++++++++++++++++------- + 1 file changed, 26 insertions(+), 7 deletions(-) + +Index: linux-2.6.18-avr32/drivers/serial/atmel_usart.c +=================================================================== +--- linux-2.6.18-avr32.orig/drivers/serial/atmel_usart.c 2006-12-18 14:59:00.000000000 +0100 ++++ linux-2.6.18-avr32/drivers/serial/atmel_usart.c 2006-12-18 16:51:33.000000000 +0100 +@@ -76,6 +76,14 @@ struct usart3_port { + struct clk *mck; + unsigned long mapsize; + struct uart_port uart; ++ ++ /* ++ * If no data is received within rx_timeout_us microseconds or ++ * rx_timeout_cycles cycles, whichever is longest, we get an ++ * interrupt. ++ */ ++ unsigned int rx_timeout_us; ++ unsigned int rx_timeout_cycles; + }; + #define to_usart3_port(port) container_of(port, struct usart3_port, uart) + +@@ -582,12 +590,6 @@ static int usart3_startup(struct uart_po + usart3_writel(up, TCR, 0); + up->tx_dma_head = port->info->xmit.tail; + +- /* +- * Set a suitable timeout. 2000 bit periods corresponds to +- * about 17 ms at 115200 bps +- */ +- usart3_writel(up, RTOR, 2000); +- + /* Reset and enable receiver and transmitter */ + usart3_writel(up, CR, (USART3_BIT(RSTRX) + | USART3_BIT(RSTTX) +@@ -633,6 +635,7 @@ static void usart3_set_termios(struct ua + struct usart3_port *up = to_usart3_port(port); + unsigned int baud, quot, mode = 0; + unsigned int imr, flags; ++ unsigned long long timeout_cycles; + + pr_debug("usart3: set_termios\n"); + +@@ -692,6 +695,13 @@ static void usart3_set_termios(struct ua + | USART3_BIT(RSTRX))); + } + ++ timeout_cycles = up->rx_timeout_us; ++ timeout_cycles *= baud; ++ do_div(timeout_cycles, 1000000); ++ if (timeout_cycles < up->rx_timeout_cycles) ++ timeout_cycles = up->rx_timeout_cycles; ++ ++ pr_debug("usart3: Setting RTOR to %llu...\n", timeout_cycles); + pr_debug("usart3: Setting BRGR to %u (baud rate %u)...\n", quot, baud); + + /* Disable receiver and transmitter */ +@@ -701,7 +711,12 @@ static void usart3_set_termios(struct ua + /* Set the parity, stop bits and data size */ + usart3_writel(up, MR, mode); + +- /* Set the baud rate and enable receiver and transmitter */ ++ /* ++ * Set the baud rate and RX timeout, and enable receiver and ++ * transmitter. ++ */ ++ usart3_writel(up, RTOR, timeout_cycles); ++ + usart3_writel(up, BRGR, quot); + usart3_writel(up, CR, (USART3_BIT(TXEN) + | USART3_BIT(RXEN))); +@@ -805,6 +820,10 @@ static int __devinit initialize_port(str + return PTR_ERR(up->mck); + clk_enable(up->mck); + ++ /* Default RX timeout after 10 ms, but no less than 10 cycles */ ++ up->rx_timeout_us = 10000; ++ up->rx_timeout_cycles = 10; ++ + port->mapbase = regs->start; + up->mapsize = regs->end - regs->start + 1; + port->irq = platform_get_irq(pdev, 0); |