diff mbox series

[v2,17/25] tty: serial: samsung_tty: Separate S3C64XX ops structure

Message ID 20210215121713.57687-18-marcan@marcan.st
State Superseded
Headers show
Series [v2,01/25] dt-bindings: vendor-prefixes: Add apple prefix | expand

Commit Message

Hector Martin Feb. 15, 2021, 12:17 p.m. UTC 
Instead of patching a single global ops structure depending on the port
type, use a separate s3c64xx_serial_ops for the S3C64XX type. This
allows us to mark the structures as const.

Also split out s3c64xx_serial_shutdown into a separate function now that
we have a separate ops structure; this avoids excessive branching
control flow and mirrors s3c64xx_serial_startup. tx_claimed and
rx_claimed are only used in the S3C24XX functions.

Signed-off-by: Hector Martin <marcan@marcan.st>
---
 drivers/tty/serial/samsung_tty.c | 69 ++++++++++++++++++++++++--------
 1 file changed, 53 insertions(+), 16 deletions(-)

Comments

Hector Martin Feb. 18, 2021, 1:24 p.m. UTC | #1 
On 16/02/2021 03.06, Krzysztof Kozlowski wrote:
> On Mon, Feb 15, 2021 at 09:17:05PM +0900, Hector Martin wrote:

>> +static void s3c64xx_serial_shutdown(struct uart_port *port)

>> +{

>> +	struct s3c24xx_uart_port *ourport = to_ourport(port);

>> +

>> +	free_irq(port->irq, ourport);

>> +

>> +	wr_regl(port, S3C64XX_UINTP, 0xf);

>> +	wr_regl(port, S3C64XX_UINTM, 0xf);

>> +

>> +	ourport->tx_enabled = 0;

>> +	ourport->tx_mode = 0;

>> +	ourport->rx_enabled = 0;

> 

> For S3C64xx type this is not equivalent: the assignments were

> happening before free_irq() and wr_regl(). Honestly I don't know whether

> it matters (except some barriers coming from these functions) but please

> do not change the order of code in this patch. If needed, the

> re-ordering should be a patch on its own. With explanation why.


Honestly, I think if anything the masking should happen first (to make 
sure no IRQs go off), but at this point it's probably better to play it 
safe and not introduce any logic changes, so I've moved the assignments 
first to retain the old behavior.

> Make the s3c24xx_serial_ops const as well.


Done for v3, thanks.

-- 
Hector Martin (marcan@marcan.st)
Public Key: https://mrcn.st/pub
diff mbox series

Patch

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index 8ae3e03fbd8c..6b661f3ec1ae 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -1098,27 +1098,36 @@  static void s3c24xx_serial_shutdown(struct uart_port *port)
 	struct s3c24xx_uart_port *ourport = to_ourport(port);
 
 	if (ourport->tx_claimed) {
-		if (!s3c24xx_serial_has_interrupt_mask(port))
-			free_irq(ourport->tx_irq, ourport);
+		free_irq(ourport->tx_irq, ourport);
 		ourport->tx_enabled = 0;
 		ourport->tx_claimed = 0;
 		ourport->tx_mode = 0;
 	}
 
 	if (ourport->rx_claimed) {
-		if (!s3c24xx_serial_has_interrupt_mask(port))
-			free_irq(ourport->rx_irq, ourport);
+		free_irq(ourport->rx_irq, ourport);
 		ourport->rx_claimed = 0;
 		ourport->rx_enabled = 0;
 	}
 
-	/* Clear pending interrupts and mask all interrupts */
-	if (s3c24xx_serial_has_interrupt_mask(port)) {
-		free_irq(port->irq, ourport);
+	if (ourport->dma)
+		s3c24xx_serial_release_dma(ourport);
 
-		wr_regl(port, S3C64XX_UINTP, 0xf);
-		wr_regl(port, S3C64XX_UINTM, 0xf);
-	}
+	ourport->tx_in_progress = 0;
+}
+
+static void s3c64xx_serial_shutdown(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+
+	free_irq(port->irq, ourport);
+
+	wr_regl(port, S3C64XX_UINTP, 0xf);
+	wr_regl(port, S3C64XX_UINTM, 0xf);
+
+	ourport->tx_enabled = 0;
+	ourport->tx_mode = 0;
+	ourport->rx_enabled = 0;
 
 	if (ourport->dma)
 		s3c24xx_serial_release_dma(ourport);
@@ -1193,9 +1202,7 @@  static int s3c64xx_serial_startup(struct uart_port *port)
 
 	/* For compatibility with s3c24xx Soc's */
 	ourport->rx_enabled = 1;
-	ourport->rx_claimed = 1;
 	ourport->tx_enabled = 0;
-	ourport->tx_claimed = 1;
 
 	spin_lock_irqsave(&port->lock, flags);
 
@@ -1631,6 +1638,29 @@  static struct uart_ops s3c24xx_serial_ops = {
 #endif
 };
 
+static const struct uart_ops s3c64xx_serial_ops = {
+	.pm		= s3c24xx_serial_pm,
+	.tx_empty	= s3c24xx_serial_tx_empty,
+	.get_mctrl	= s3c24xx_serial_get_mctrl,
+	.set_mctrl	= s3c24xx_serial_set_mctrl,
+	.stop_tx	= s3c24xx_serial_stop_tx,
+	.start_tx	= s3c24xx_serial_start_tx,
+	.stop_rx	= s3c24xx_serial_stop_rx,
+	.break_ctl	= s3c24xx_serial_break_ctl,
+	.startup	= s3c64xx_serial_startup,
+	.shutdown	= s3c64xx_serial_shutdown,
+	.set_termios	= s3c24xx_serial_set_termios,
+	.type		= s3c24xx_serial_type,
+	.release_port	= s3c24xx_serial_release_port,
+	.request_port	= s3c24xx_serial_request_port,
+	.config_port	= s3c24xx_serial_config_port,
+	.verify_port	= s3c24xx_serial_verify_port,
+#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
+	.poll_get_char = s3c24xx_serial_get_poll_char,
+	.poll_put_char = s3c24xx_serial_put_poll_char,
+#endif
+};
+
 static struct uart_driver s3c24xx_uart_drv = {
 	.owner		= THIS_MODULE,
 	.driver_name	= "s3c2410_serial",
@@ -1868,10 +1898,6 @@  static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
 	/* setup info for port */
 	port->dev	= &platdev->dev;
 
-	/* Startup sequence is different for s3c64xx and higher SoC's */
-	if (s3c24xx_serial_has_interrupt_mask(port))
-		s3c24xx_serial_ops.startup = s3c64xx_serial_startup;
-
 	port->uartclk = 1;
 
 	if (cfg->uart_flags & UPF_CONS_FLOW) {
@@ -2019,6 +2045,17 @@  static int s3c24xx_serial_probe(struct platform_device *pdev)
 			dev_get_platdata(&pdev->dev) :
 			ourport->drv_data->def_cfg;
 
+	switch (ourport->info->type) {
+	case PORT_S3C2410:
+	case PORT_S3C2412:
+	case PORT_S3C2440:
+		ourport->port.ops = &s3c24xx_serial_ops;
+		break;
+	case PORT_S3C6400:
+		ourport->port.ops = &s3c64xx_serial_ops;
+		break;
+	}
+
 	if (np) {
 		of_property_read_u32(np,
 			"samsung,uart-fifosize", &ourport->port.fifosize);