diff options
author | 2017-03-08 23:13:28 -0800 | |
---|---|---|
committer | 2017-03-08 23:36:15 -0800 | |
commit | 52f993b8e89487ec9ee15a7fb4979e0f09a45b27 (patch) | |
tree | d65304486afe0bea4a311c783c0d72791c8c0aa2 /kernel/drivers/tty/serial/atmel_serial.c | |
parent | c189ccac5702322ed843fe17057035b7222a59b6 (diff) |
Upgrade to 4.4.50-rt62
The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it
to 4.4.50-rt62.
The command to achieve it is:
a) Clone a git repo from
git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git
b) Get the diff between this two changesets:
git diff 640eca2901f3435e616157b11379d3223a44b391
705619beeea1b0b48219a683fd1a901a86fdaf5e
where the two commits are:
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
640eca2901f3435e616157b11379d3223a44b391
640eca2901f3 v4.4.6-rt14
localversion-rt
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
705619beeea1b0b48219a683fd1a901a86fdaf5e
705619beeea1 Linux 4.4.50-rt62
localversion-rt
c) One patch has been backported thus revert the patch before applying.
filterdiff -p1 -x scripts/package/Makefile
~/tmp/v4.4.6-rt14-4.4.50-rt62.diff |patch -p1 --dry-run
Upstream status: backport
Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01
Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>
Diffstat (limited to 'kernel/drivers/tty/serial/atmel_serial.c')
-rw-r--r-- | kernel/drivers/tty/serial/atmel_serial.c | 58 |
1 files changed, 51 insertions, 7 deletions
diff --git a/kernel/drivers/tty/serial/atmel_serial.c b/kernel/drivers/tty/serial/atmel_serial.c index 942945589..a0f911641 100644 --- a/kernel/drivers/tty/serial/atmel_serial.c +++ b/kernel/drivers/tty/serial/atmel_serial.c @@ -277,6 +277,13 @@ static bool atmel_use_dma_rx(struct uart_port *port) return atmel_port->use_dma_rx; } +static bool atmel_use_fifo(struct uart_port *port) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + + return atmel_port->fifo_size; +} + static unsigned int atmel_get_lines_status(struct uart_port *port) { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); @@ -463,6 +470,14 @@ static void atmel_stop_tx(struct uart_port *port) /* disable PDC transmit */ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS); } + + /* + * Disable the transmitter. + * This is mandatory when DMA is used, otherwise the DMA buffer + * is fully transmitted. + */ + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXDIS); + /* Disable interrupts */ atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask); @@ -478,21 +493,26 @@ static void atmel_start_tx(struct uart_port *port) { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); - if (atmel_use_pdc_tx(port)) { - if (atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN) - /* The transmitter is already running. Yes, we - really need this.*/ - return; + if (atmel_use_pdc_tx(port) && (atmel_uart_readl(port, ATMEL_PDC_PTSR) + & ATMEL_PDC_TXTEN)) + /* The transmitter is already running. Yes, we + really need this.*/ + return; + if (atmel_use_pdc_tx(port) || atmel_use_dma_tx(port)) if ((port->rs485.flags & SER_RS485_ENABLED) && !(port->rs485.flags & SER_RS485_RX_DURING_TX)) atmel_stop_rx(port); + if (atmel_use_pdc_tx(port)) /* re-enable PDC transmit */ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN); - } + /* Enable interrupts */ atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask); + + /* re-enable the transmitter */ + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN); } /* @@ -2066,6 +2086,7 @@ static void atmel_serial_pm(struct uart_port *port, unsigned int state, static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) { + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); unsigned long flags; unsigned int old_mode, mode, imr, quot, baud; @@ -2169,7 +2190,30 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, mode |= ATMEL_US_USMODE_RS485; } else if (termios->c_cflag & CRTSCTS) { /* RS232 with hardware handshake (RTS/CTS) */ - mode |= ATMEL_US_USMODE_HWHS; + if (atmel_use_fifo(port) && + !mctrl_gpio_to_gpiod(atmel_port->gpios, UART_GPIO_CTS)) { + /* + * with ATMEL_US_USMODE_HWHS set, the controller will + * be able to drive the RTS pin high/low when the RX + * FIFO is above RXFTHRES/below RXFTHRES2. + * It will also disable the transmitter when the CTS + * pin is high. + * This mode is not activated if CTS pin is a GPIO + * because in this case, the transmitter is always + * disabled (there must be an internal pull-up + * responsible for this behaviour). + * If the RTS pin is a GPIO, the controller won't be + * able to drive it according to the FIFO thresholds, + * but it will be handled by the driver. + */ + mode |= ATMEL_US_USMODE_HWHS; + } else { + /* + * For platforms without FIFO, the flow control is + * handled by the driver. + */ + mode |= ATMEL_US_USMODE_NORMAL; + } } else { /* RS232 without hadware handshake */ mode |= ATMEL_US_USMODE_NORMAL; |