From: Manikanta Guntupalli <manikanta.guntupalli@amd.com>
To: <git@amd.com>, <gregkh@linuxfoundation.org>,
<jirislaby@kernel.org>, <robh@kernel.org>, <krzk+dt@kernel.org>,
<conor+dt@kernel.org>, <michal.simek@amd.com>,
<p.zabel@pengutronix.de>, <laurent.pinchart@ideasonboard.com>,
<radhey.shyam.pandey@amd.com>, <parth.gajjar@amd.com>,
<u.kleine-koenig@pengutronix.de>, <tglx@linutronix.de>,
<julien.malik@unseenlabs.fr>, <ruanjinjie@huawei.com>,
<linux-kernel@vger.kernel.org>, <linux-serial@vger.kernel.org>,
<devicetree@vger.kernel.org>,
<linux-arm-kernel@lists.infradead.org>
Cc: <srinivas.goud@amd.com>, <shubhrajyoti.datta@amd.com>,
<manion05gk@gmail.com>,
Manikanta Guntupalli <manikanta.guntupalli@amd.com>
Subject: [PATCH V3 3/3] tty: serial: uartps: Add support for uartps controller reset
Date: Thu, 25 Apr 2024 11:53:58 +0530 [thread overview]
Message-ID: <20240425062358.1347684-4-manikanta.guntupalli@amd.com> (raw)
In-Reply-To: <20240425062358.1347684-1-manikanta.guntupalli@amd.com>
Add support for an optional reset for the uartps controller using
the reset driver. If the uartps node contains the "resets" property,
then cdns_uart_startup performs uartps controller non-pulse out of reset
and reset in exit path.
Signed-off-by: Manikanta Guntupalli <manikanta.guntupalli@amd.com>
---
Changes for V2:
Remove check for reset_control_deassert, as reset_control_deassert
function internally has NULL check.
Changes for V3:
None.
---
drivers/tty/serial/xilinx_uartps.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index de3487206bcb..2acfcea403ce 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -25,6 +25,7 @@
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/delay.h>
+#include <linux/reset.h>
#define CDNS_UART_TTY_NAME "ttyPS"
#define CDNS_UART_NAME "xuartps"
@@ -198,6 +199,7 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
* @gpiod_rts: Pointer to the gpio descriptor
* @rs485_tx_started: RS485 tx state
* @tx_timer: Timer for tx
+ * @rstc: Pointer to the reset control
*/
struct cdns_uart {
struct uart_port *port;
@@ -211,6 +213,7 @@ struct cdns_uart {
struct gpio_desc *gpiod_rts;
bool rs485_tx_started;
struct hrtimer tx_timer;
+ struct reset_control *rstc;
};
struct cdns_platform_data {
u32 quirks;
@@ -948,6 +951,10 @@ static int cdns_uart_startup(struct uart_port *port)
is_brk_support = cdns_uart->quirks & CDNS_UART_RXBS_SUPPORT;
+ ret = reset_control_deassert(cdns_uart->rstc);
+ if (ret)
+ return ret;
+
uart_port_lock_irqsave(port, &flags);
/* Disable the TX and RX */
@@ -1721,6 +1728,13 @@ static int cdns_uart_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "clock name 'ref_clk' is deprecated.\n");
}
+ cdns_uart_data->rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(cdns_uart_data->rstc)) {
+ rc = PTR_ERR(cdns_uart_data->rstc);
+ dev_err_probe(&pdev->dev, rc, "Cannot get UART reset\n");
+ goto err_out_unregister_driver;
+ }
+
rc = clk_prepare_enable(cdns_uart_data->pclk);
if (rc) {
dev_err(&pdev->dev, "Unable to enable pclk clock.\n");
@@ -1881,6 +1895,7 @@ static void cdns_uart_remove(struct platform_device *pdev)
if (console_port == port)
console_port = NULL;
#endif
+ reset_control_assert(cdns_uart_data->rstc);
if (!--instances)
uart_unregister_driver(cdns_uart_data->cdns_uart_driver);
--
2.25.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
prev parent reply other threads:[~2024-04-25 6:25 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-25 6:23 [PATCH V3 0/3] Add support for uartps controller reset Manikanta Guntupalli
2024-04-25 6:23 ` [PATCH V3 1/3] dt-bindings: serial: cdns,uart: Add optional reset property Manikanta Guntupalli
2024-04-25 6:23 ` [PATCH V3 2/3] arm64: zynqmp: Add resets property for UART nodes Manikanta Guntupalli
2024-05-24 9:48 ` Michal Simek
2024-04-25 6:23 ` Manikanta Guntupalli [this message]
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=20240425062358.1347684-4-manikanta.guntupalli@amd.com \
--to=manikanta.guntupalli@amd.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=git@amd.com \
--cc=gregkh@linuxfoundation.org \
--cc=jirislaby@kernel.org \
--cc=julien.malik@unseenlabs.fr \
--cc=krzk+dt@kernel.org \
--cc=laurent.pinchart@ideasonboard.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
--cc=manion05gk@gmail.com \
--cc=michal.simek@amd.com \
--cc=p.zabel@pengutronix.de \
--cc=parth.gajjar@amd.com \
--cc=radhey.shyam.pandey@amd.com \
--cc=robh@kernel.org \
--cc=ruanjinjie@huawei.com \
--cc=shubhrajyoti.datta@amd.com \
--cc=srinivas.goud@amd.com \
--cc=tglx@linutronix.de \
--cc=u.kleine-koenig@pengutronix.de \
/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;
as well as URLs for NNTP newsgroup(s).