[PATCH v2 0/6] serial: meson: series with smaller fixes and improvements

[PATCH v2 0/6] serial: meson: series with smaller fixes and improvements

[Heiner Kallweit]

This series includes a few smaller fixes and improvements for the
meson uart driver.

Changes in v2:
- change patch 3 based on review discussion
- change patch 6 to use port->name instead

Heiner Kallweit (6):
  serial: meson: fix setting number of stop bits
  serial: meson: remove dead code in meson_uart_change_speed
  serial: meson: remove unneeded variable assignment in meson_serial_port_write
  serial: meson: make use of uart_port member mapsize
  serial: meson: remove use of flag UPF_IOREMAP
  serial: meson: change interrupt description to of node name

 drivers/tty/serial/meson_uart.c | 68 ++++++++++++++++-------------------------
 1 file changed, 26 insertions(+), 42 deletions(-)

-- 
2.12.2

[PATCH v2 1/6] serial: meson: fix setting number of stop bits

[Heiner Kallweit]

The stop bit value as to be or'ed, so far this worked only just by chance
because AML_UART_STOP_BIN_1SB is 0.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- no changes
---
 drivers/tty/serial/meson_uart.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 60f16795..e2e25da1 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -355,7 +355,7 @@ static void meson_uart_set_termios(struct uart_port *port,
 	if (cflags & CSTOPB)
 		val |= AML_UART_STOP_BIN_2SB;
 	else
-		val &= ~AML_UART_STOP_BIN_1SB;
+		val |= AML_UART_STOP_BIN_1SB;
 
 	if (cflags & CRTSCTS)
 		val &= ~AML_UART_TWO_WIRE_EN;
-- 
2.12.2

[PATCH v2 2/6] serial: meson: remove dead code in meson_uart_change_speed

[Heiner Kallweit]

val is set in both branches of the if clause, therefore the two
removed lines are dead code.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- no changes
---
 drivers/tty/serial/meson_uart.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index e2e25da1..22857f1e 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -298,8 +298,6 @@ static void meson_uart_change_speed(struct uart_port *port, unsigned long baud)
 	while (!meson_uart_tx_empty(port))
 		cpu_relax();
 
-	val = readl(port->membase + AML_UART_REG5);
-	val &= ~AML_UART_BAUD_MASK;
 	if (port->uartclk == 24000000) {
 		val = ((port->uartclk / 3) / baud) - 1;
 		val |= AML_UART_BAUD_XTAL;
-- 
2.12.2

[PATCH v2 3/6] serial: meson: remove unneeded variable assignment in meson_serial_port_write

[Heiner Kallweit]

There's no need to set AML_UART_TX_EN in each call to
meson_serial_port_write. In addition to meson_uart_startup
set this flag in meson_serial_console_setup and
meson_serial_early_console_setup.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- enable AML_UART_TX_EN in both console setup functions
---
 drivers/tty/serial/meson_uart.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 22857f1e..e93a1e47 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -124,6 +124,15 @@ static void meson_uart_stop_rx(struct uart_port *port)
 	writel(val, port->membase + AML_UART_CONTROL);
 }
 
+static void meson_uart_enable_tx_engine(struct uart_port *port)
+{
+	u32 val;
+
+	val = readl(port->membase + AML_UART_CONTROL);
+	val |= AML_UART_TX_EN;
+	writel(val, port->membase + AML_UART_CONTROL);
+}
+
 static void meson_uart_shutdown(struct uart_port *port)
 {
 	unsigned long flags;
@@ -497,7 +506,6 @@ static void meson_serial_port_write(struct uart_port *port, const char *s,
 	}
 
 	val = readl(port->membase + AML_UART_CONTROL);
-	val |= AML_UART_TX_EN;
 	tmp = val & ~(AML_UART_TX_INT_EN | AML_UART_RX_INT_EN);
 	writel(tmp, port->membase + AML_UART_CONTROL);
 
@@ -536,6 +544,8 @@ static int meson_serial_console_setup(struct console *co, char *options)
 	if (!port || !port->membase)
 		return -ENODEV;
 
+	meson_uart_enable_tx_engine(port);
+
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 
@@ -574,6 +584,7 @@ meson_serial_early_console_setup(struct earlycon_device *device, const char *opt
 	if (!device->port.membase)
 		return -ENODEV;
 
+	meson_uart_enable_tx_engine(&device->port);
 	device->con->write = meson_serial_early_console_write;
 	return 0;
 }
-- 
2.12.2

[PATCH v2 4/6] serial: meson: make use of uart_port member mapsize

[Heiner Kallweit]

Member mapsize of struct uart_port is meant to store the resource size.
By using it we can get rid of meson_uart_res_size().

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- no changes
---
 drivers/tty/serial/meson_uart.c | 29 +++++------------------------
 1 file changed, 5 insertions(+), 24 deletions(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index e93a1e47..1220c9ac 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -402,26 +402,11 @@ static int meson_uart_verify_port(struct uart_port *port,
 	return ret;
 }
 
-static int meson_uart_res_size(struct uart_port *port)
-{
-	struct platform_device *pdev = to_platform_device(port->dev);
-	struct resource *res;
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		dev_err(port->dev, "cannot obtain I/O memory region");
-		return -ENODEV;
-	}
-
-	return resource_size(res);
-}
-
 static void meson_uart_release_port(struct uart_port *port)
 {
-	int size = meson_uart_res_size(port);
-
 	if (port->flags & UPF_IOREMAP) {
-		devm_release_mem_region(port->dev, port->mapbase, size);
+		devm_release_mem_region(port->dev, port->mapbase,
+					port->mapsize);
 		devm_iounmap(port->dev, port->membase);
 		port->membase = NULL;
 	}
@@ -429,12 +414,7 @@ static void meson_uart_release_port(struct uart_port *port)
 
 static int meson_uart_request_port(struct uart_port *port)
 {
-	int size = meson_uart_res_size(port);
-
-	if (size < 0)
-		return size;
-
-	if (!devm_request_mem_region(port->dev, port->mapbase, size,
+	if (!devm_request_mem_region(port->dev, port->mapbase, port->mapsize,
 				     dev_name(port->dev))) {
 		dev_err(port->dev, "Memory region busy\n");
 		return -EBUSY;
@@ -443,7 +423,7 @@ static int meson_uart_request_port(struct uart_port *port)
 	if (port->flags & UPF_IOREMAP) {
 		port->membase = devm_ioremap_nocache(port->dev,
 						     port->mapbase,
-						     size);
+						     port->mapsize);
 		if (port->membase == NULL)
 			return -ENOMEM;
 	}
@@ -641,6 +621,7 @@ static int meson_uart_probe(struct platform_device *pdev)
 	port->uartclk = clk_get_rate(clk);
 	port->iotype = UPIO_MEM;
 	port->mapbase = res_mem->start;
+	port->mapsize = resource_size(res_mem);
 	port->irq = res_irq->start;
 	port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP | UPF_LOW_LATENCY;
 	port->dev = &pdev->dev;
-- 
2.12.2

[PATCH v2 5/6] serial: meson: remove use of flag UPF_IOREMAP

[Heiner Kallweit]

Flag UPF_IOREMAP is used by the 8250 subsystem only, it's not used
by the serial core. Therefore I don't see any benefit in using it
here.

In addition fix the order of calls in meson_uart_release_port.
Unmapping needs to be done first, reversing call order in
meson_uart_request_port.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- no changes
---
 drivers/tty/serial/meson_uart.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 1220c9ac..171eb673 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -404,12 +404,9 @@ static int meson_uart_verify_port(struct uart_port *port,
 
 static void meson_uart_release_port(struct uart_port *port)
 {
-	if (port->flags & UPF_IOREMAP) {
-		devm_release_mem_region(port->dev, port->mapbase,
-					port->mapsize);
-		devm_iounmap(port->dev, port->membase);
-		port->membase = NULL;
-	}
+	devm_iounmap(port->dev, port->membase);
+	port->membase = NULL;
+	devm_release_mem_region(port->dev, port->mapbase, port->mapsize);
 }
 
 static int meson_uart_request_port(struct uart_port *port)
@@ -420,13 +417,10 @@ static int meson_uart_request_port(struct uart_port *port)
 		return -EBUSY;
 	}
 
-	if (port->flags & UPF_IOREMAP) {
-		port->membase = devm_ioremap_nocache(port->dev,
-						     port->mapbase,
-						     port->mapsize);
-		if (port->membase == NULL)
-			return -ENOMEM;
-	}
+	port->membase = devm_ioremap_nocache(port->dev, port->mapbase,
+					     port->mapsize);
+	if (!port->membase)
+		return -ENOMEM;
 
 	return 0;
 }
@@ -623,7 +617,7 @@ static int meson_uart_probe(struct platform_device *pdev)
 	port->mapbase = res_mem->start;
 	port->mapsize = resource_size(res_mem);
 	port->irq = res_irq->start;
-	port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP | UPF_LOW_LATENCY;
+	port->flags = UPF_BOOT_AUTOCONF | UPF_LOW_LATENCY;
 	port->dev = &pdev->dev;
 	port->line = pdev->id;
 	port->type = PORT_MESON;
-- 
2.12.2

[PATCH v2 6/6] serial: meson: change interrupt description to tty name

[Heiner Kallweit]

Change interrupt description from driver name to tty name
(e.g. ttyAML0). If multiple serial ports are enabled this
allows to determine which interrupt belongs to which port
in /proc/interrupts.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- use new port->name instead of of node name
---
 drivers/tty/serial/meson_uart.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 171eb673..082e038e 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -295,7 +295,7 @@ static int meson_uart_startup(struct uart_port *port)
 	writel(val, port->membase + AML_UART_MISC);
 
 	ret = request_irq(port->irq, meson_uart_interrupt, 0,
-			  meson_uart_type(port), port);
+			  port->name, port);
 
 	return ret;
 }
-- 
2.12.2

[PATCH v2 6/6] serial: meson: change interrupt description to tty name

[Yixun Lan]

On 22:18 Wed 19 Apr     , Heiner Kallweit wrote:
> Change interrupt description from driver name to tty name
> (e.g. ttyAML0). If multiple serial ports are enabled this
> allows to determine which interrupt belongs to which port
> in /proc/interrupts.
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
> v2:
> - use new port->name instead of of node name
> ---
>  drivers/tty/serial/meson_uart.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
> index 171eb673..082e038e 100644
> --- a/drivers/tty/serial/meson_uart.c
> +++ b/drivers/tty/serial/meson_uart.c
> @@ -295,7 +295,7 @@ static int meson_uart_startup(struct uart_port *port)
>  	writel(val, port->membase + AML_UART_MISC);
>  
>  	ret = request_irq(port->irq, meson_uart_interrupt, 0,
> -			  meson_uart_type(port), port);
> +			  port->name, port);
>  
>  	return ret;
>  }
> -- 
> 2.12.2
> 
> 
> 
> _______________________________________________
> linux-amlogic mailing list
> linux-amlogic at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-amlogic

Hi Heiner Kallweit:

there is no member of 'name' in 'struct uart_port'
or did I miss something obviously?
(btw, I'm applying these patches on top of khilman's tree: branch v4.12/integ)

as I got this error:

drivers/tty/serial/meson_uart.c: In function ?meson_uart_startup?:                
drivers/tty/serial/meson_uart.c:298:10: error: ?struct uart_port? has no
member named ?name?
      port->name, port);                         
          ^~                                                              
make[3]: *** [scripts/Makefile.build:294: drivers/tty/serial/meson_uart.o] Error 1
make[3]: *** Waiting for unfinished jobs....  

-- 
Yixun Lan (dlan)
Gentoo Linux Developer
GPG Key ID AABEFD55