From: Soren Brinkmann <soren.brinkmann@xilinx.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jslaby@suse.cz>,
Michal Simek <michal.simek@xilinx.com>
Cc: linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
Vlad Lungu <vlad.lungu@windriver.com>,
Soren Brinkmann <soren.brinkmann@xilinx.com>
Subject: [PATCH 04/10] tty: xuartps: Add polled mode support for xuartps
Date: Thu, 17 Oct 2013 14:08:07 -0700 [thread overview]
Message-ID: <1382044093-29905-5-git-send-email-soren.brinkmann@xilinx.com> (raw)
In-Reply-To: <1382044093-29905-1-git-send-email-soren.brinkmann@xilinx.com>
From: Vlad Lungu <vlad.lungu@windriver.com>
This allows KDB/KGDB to run.
Signed-off-by: Vlad Lungu <vlad.lungu@windriver.com>
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
---
This is squashed from these original patches:
tty: xuartps: Add polled mode support for xuartps
This allows KDB/KGDB to run.
There is a bug somewhere that blocks KDB when paging;
set the LINES environment variable to a big value and
scroll in your terminal.
Signed-off-by: Vlad Lungu <vlad.lungu@windriver.com>
and
tty: xuartps: Fix poll read
This fixes the KDB paging issue.
Signed-off-by: Vlad Lungu <vlad.lungu@windriver.com>
Additionally I fixed a few style issues.
---
drivers/tty/serial/xilinx_uartps.c | 52 ++++++++++++++++++++++++++++++++++++++
1 file changed, 52 insertions(+)
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 5d5557af4d22..62259f37ddda 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -775,6 +775,54 @@ static void xuartps_enable_ms(struct uart_port *port)
/* N/A */
}
+#ifdef CONFIG_CONSOLE_POLL
+static int xuartps_poll_get_char(struct uart_port *port)
+{
+ u32 imr;
+ int c;
+
+ /* Disable all interrupts */
+ imr = xuartps_readl(XUARTPS_IMR_OFFSET);
+ xuartps_writel(imr, XUARTPS_IDR_OFFSET);
+
+ /* Check if FIFO is empty */
+ if (xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_RXEMPTY)
+ c = NO_POLL_CHAR;
+ else /* Read a character */
+ c = (unsigned char) xuartps_readl(XUARTPS_FIFO_OFFSET);
+
+ /* Enable interrupts */
+ xuartps_writel(imr, XUARTPS_IER_OFFSET);
+
+ return c;
+}
+
+static void xuartps_poll_put_char(struct uart_port *port, unsigned char c)
+{
+ u32 imr;
+
+ /* Disable all interrupts */
+ imr = xuartps_readl(XUARTPS_IMR_OFFSET);
+ xuartps_writel(imr, XUARTPS_IDR_OFFSET);
+
+ /* Wait until FIFO is empty */
+ while (!(xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_TXEMPTY))
+ cpu_relax();
+
+ /* Write a character */
+ xuartps_writel(c, XUARTPS_FIFO_OFFSET);
+
+ /* Wait until FIFO is empty */
+ while (!(xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_TXEMPTY))
+ cpu_relax();
+
+ /* Enable interrupts */
+ xuartps_writel(imr, XUARTPS_IER_OFFSET);
+
+ return;
+}
+#endif
+
/** The UART operations structure
*/
static struct uart_ops xuartps_ops = {
@@ -807,6 +855,10 @@ static struct uart_ops xuartps_ops = {
.config_port = xuartps_config_port, /* Configure when driver
* adds a xuartps port
*/
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = xuartps_poll_get_char,
+ .poll_put_char = xuartps_poll_put_char,
+#endif
};
static struct uart_port xuartps_port[2];
--
1.8.4.1
next prev parent reply other threads:[~2013-10-17 21:16 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-17 21:08 [PATCH 00/10] tty: xuartps: Update Soren Brinkmann
2013-10-17 21:08 ` [PATCH 01/10] tty: xuartps: Use devm_clk_get() Soren Brinkmann
2013-10-17 21:08 ` [PATCH 02/10] tty: xuartps: Use devm_kzalloc Soren Brinkmann
2013-10-17 21:08 ` [PATCH 03/10] tty: xuartps: Implement BREAK detection, add SYSRQ support Soren Brinkmann
2013-12-02 20:42 ` Peter Hurley
2013-10-17 21:08 ` Soren Brinkmann [this message]
2013-10-17 21:08 ` [PATCH 05/10] tty: xuartps: support 64 byte FIFO size Soren Brinkmann
2013-10-17 21:08 ` [PATCH 06/10] tty: xuartps: Force enable the UART in xuartps_console_write Soren Brinkmann
2013-10-17 21:08 ` [PATCH 07/10] tty: xuartps: Updating set_baud_rate() Soren Brinkmann
2013-10-17 21:08 ` [PATCH 08/10] tty: xuartps: Dynamically adjust to input frequency changes Soren Brinkmann
2013-10-17 21:08 ` [PATCH 09/10] tty: xuartps: Implement suspend/resume callbacks Soren Brinkmann
2013-10-17 21:08 ` [PATCH 10/10] tty: xuartps: Update copyright information Soren Brinkmann
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1382044093-29905-5-git-send-email-soren.brinkmann@xilinx.com \
--to=soren.brinkmann@xilinx.com \
--cc=gregkh@linuxfoundation.org \
--cc=jslaby@suse.cz \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
--cc=michal.simek@xilinx.com \
--cc=vlad.lungu@windriver.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®