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* [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups
@ 2020-01-16 12:14 Lukas Wunner
  2020-01-16 12:14 ` [PATCH 1/6] serial: 8250_bcm2835aux: Fix line mismatch on driver unbind Lukas Wunner
                   ` (6 more replies)
  0 siblings, 7 replies; 12+ messages in thread
From: Lukas Wunner @ 2020-01-16 12:14 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Jiri Slaby, Nicolas Saenz Julienne, linux-serial,
	linux-rpi-kernel, Martin Sperl, Phil Elwell

Here's a collection of fixes & cleanups for the Raspberry Pi auxiliary UART
to prepare for upcoming feature work on the driver.

With compliments from Revolution Pi labs (https://revolution.kunbus.com/).

Lukas Wunner (5):
  serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
  serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  serial: 8250_bcm2835aux: Use generic remapping code
  serial: 8250_bcm2835aux: Document struct bcm2835aux_data

Phil Elwell (1):
  serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER

 drivers/tty/serial/8250/8250_bcm2835aux.c | 50 ++++++++++++-----------
 1 file changed, 26 insertions(+), 24 deletions(-)

-- 
2.24.0


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH 1/6] serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
  2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
@ 2020-01-16 12:14 ` Lukas Wunner
  2020-01-16 12:14 ` [PATCH 2/6] serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER Lukas Wunner
                   ` (5 subsequent siblings)
  6 siblings, 0 replies; 12+ messages in thread
From: Lukas Wunner @ 2020-01-16 12:14 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Jiri Slaby, Nicolas Saenz Julienne, linux-serial,
	linux-rpi-kernel, Martin Sperl

Unbinding the bcm2835aux UART driver raises the following error if the
maximum number of 8250 UARTs is set to 1 (via the 8250.nr_uarts module
parameter or CONFIG_SERIAL_8250_RUNTIME_UARTS):

(NULL device *): Removing wrong port: a6f80333 != fa20408b

That's because bcm2835aux_serial_probe() retrieves UART line number 1
from the devicetree and stores it in data->uart.port.line, while
serial8250_register_8250_port() instead uses UART line number 0,
which is stored in data->line.

On driver unbind, bcm2835aux_serial_remove() uses data->uart.port.line,
which contains the wrong number.  Fix it.

The issue does not occur if the maximum number of 8250 UARTs is >= 2.

Fixes: bdc5f3009580 ("serial: bcm2835: add driver for bcm2835-aux-uart")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.6+
Cc: Martin Sperl <kernel@martin.sperl.org>
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index 8ce700c1a7fc..4997c519ebb3 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -113,7 +113,7 @@ static int bcm2835aux_serial_remove(struct platform_device *pdev)
 {
 	struct bcm2835aux_data *data = platform_get_drvdata(pdev);
 
-	serial8250_unregister_port(data->uart.port.line);
+	serial8250_unregister_port(data->line);
 	clk_disable_unprepare(data->clk);
 
 	return 0;
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 2/6] serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
  2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
  2020-01-16 12:14 ` [PATCH 1/6] serial: 8250_bcm2835aux: Fix line mismatch on driver unbind Lukas Wunner
@ 2020-01-16 12:14 ` Lukas Wunner
  2020-01-16 12:58   ` Matthias Brugger
  2020-01-16 12:14 ` [PATCH 3/6] serial: 8250_bcm2835aux: Suppress register_port " Lukas Wunner
                   ` (4 subsequent siblings)
  6 siblings, 1 reply; 12+ messages in thread
From: Lukas Wunner @ 2020-01-16 12:14 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Jiri Slaby, Nicolas Saenz Julienne, linux-serial,
	linux-rpi-kernel, Martin Sperl, Phil Elwell

From: Phil Elwell <phil@raspberrypi.org>

Suppress a gratuitous error message if devm_clk_get() returns
-EPROBE_DEFER.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
[lukas: extend commit message]
Signed-off-by: Lukas Wunner <lukas@wunner.de>
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index 4997c519ebb3..33da68341c3a 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -50,7 +50,8 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	data->clk = devm_clk_get(&pdev->dev, NULL);
 	ret = PTR_ERR_OR_ZERO(data->clk);
 	if (ret) {
-		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "could not get clk: %d\n", ret);
 		return ret;
 	}
 
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 3/6] serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
  2020-01-16 12:14 ` [PATCH 1/6] serial: 8250_bcm2835aux: Fix line mismatch on driver unbind Lukas Wunner
  2020-01-16 12:14 ` [PATCH 2/6] serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER Lukas Wunner
@ 2020-01-16 12:14 ` Lukas Wunner
  2020-01-16 12:58   ` Matthias Brugger
  2020-01-16 12:14 ` [PATCH 4/6] serial: 8250_bcm2835aux: Allocate uart_8250_port on stack Lukas Wunner
                   ` (3 subsequent siblings)
  6 siblings, 1 reply; 12+ messages in thread
From: Lukas Wunner @ 2020-01-16 12:14 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Jiri Slaby, Nicolas Saenz Julienne, linux-serial,
	linux-rpi-kernel, Martin Sperl

Suppress a gratuitous error message if serial8250_register_8250_port()
returns -EPROBE_DEFER.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index 33da68341c3a..fb850d0ad643 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -95,8 +95,9 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	/* register the port */
 	ret = serial8250_register_8250_port(&data->uart);
 	if (ret < 0) {
-		dev_err(&pdev->dev, "unable to register 8250 port - %d\n",
-			ret);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev,
+				"unable to register 8250 port - %d\n", ret);
 		goto dis_clk;
 	}
 	data->line = ret;
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 4/6] serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
                   ` (2 preceding siblings ...)
  2020-01-16 12:14 ` [PATCH 3/6] serial: 8250_bcm2835aux: Suppress register_port " Lukas Wunner
@ 2020-01-16 12:14 ` Lukas Wunner
  2020-01-16 13:06   ` Matthias Brugger
  2020-01-16 12:14 ` [PATCH 5/6] serial: 8250_bcm2835aux: Use generic remapping code Lukas Wunner
                   ` (2 subsequent siblings)
  6 siblings, 1 reply; 12+ messages in thread
From: Lukas Wunner @ 2020-01-16 12:14 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Jiri Slaby, Nicolas Saenz Julienne, linux-serial,
	linux-rpi-kernel, Martin Sperl

The bcm2835aux UART driver stores a struct uart_8250_port in its private
data even though it's only passed once to serial8250_register_8250_port()
(which copies all relevant data) and becomes obsolete afterwards.
Allocate the struct on the stack instead for simplicity and to conserve
memory.

The driver also initializes a spinlock in the struct which is never used.
Drop that as well.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 33 +++++++++++------------
 1 file changed, 15 insertions(+), 18 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index fb850d0ad643..f03d38e7c3a7 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -17,13 +17,13 @@
 #include "8250.h"
 
 struct bcm2835aux_data {
-	struct uart_8250_port uart;
 	struct clk *clk;
 	int line;
 };
 
 static int bcm2835aux_serial_probe(struct platform_device *pdev)
 {
+	struct uart_8250_port up = { };
 	struct bcm2835aux_data *data;
 	struct resource *res;
 	int ret;
@@ -34,17 +34,14 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	/* initialize data */
-	spin_lock_init(&data->uart.port.lock);
-	data->uart.capabilities = UART_CAP_FIFO | UART_CAP_MINI;
-	data->uart.port.dev = &pdev->dev;
-	data->uart.port.regshift = 2;
-	data->uart.port.type = PORT_16550;
-	data->uart.port.iotype = UPIO_MEM;
-	data->uart.port.fifosize = 8;
-	data->uart.port.flags = UPF_SHARE_IRQ |
-				UPF_FIXED_PORT |
-				UPF_FIXED_TYPE |
-				UPF_SKIP_TEST;
+	up.capabilities = UART_CAP_FIFO | UART_CAP_MINI;
+	up.port.dev = &pdev->dev;
+	up.port.regshift = 2;
+	up.port.type = PORT_16550;
+	up.port.iotype = UPIO_MEM;
+	up.port.fifosize = 8;
+	up.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE |
+			UPF_SKIP_TEST;
 
 	/* get the clock - this also enables the HW */
 	data->clk = devm_clk_get(&pdev->dev, NULL);
@@ -59,7 +56,7 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	ret = platform_get_irq(pdev, 0);
 	if (ret < 0)
 		return ret;
-	data->uart.port.irq = ret;
+	up.port.irq = ret;
 
 	/* map the main registers */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -67,15 +64,15 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "memory resource not found");
 		return -EINVAL;
 	}
-	data->uart.port.membase = devm_ioremap_resource(&pdev->dev, res);
-	ret = PTR_ERR_OR_ZERO(data->uart.port.membase);
+	up.port.membase = devm_ioremap_resource(&pdev->dev, res);
+	ret = PTR_ERR_OR_ZERO(up.port.membase);
 	if (ret)
 		return ret;
 
 	/* Check for a fixed line number */
 	ret = of_alias_get_id(pdev->dev.of_node, "serial");
 	if (ret >= 0)
-		data->uart.port.line = ret;
+		up.port.line = ret;
 
 	/* enable the clock as a last step */
 	ret = clk_prepare_enable(data->clk);
@@ -90,10 +87,10 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	 * so we have to multiply the actual clock by 2
 	 * to get identical baudrates.
 	 */
-	data->uart.port.uartclk = clk_get_rate(data->clk) * 2;
+	up.port.uartclk = clk_get_rate(data->clk) * 2;
 
 	/* register the port */
-	ret = serial8250_register_8250_port(&data->uart);
+	ret = serial8250_register_8250_port(&up);
 	if (ret < 0) {
 		if (ret != -EPROBE_DEFER)
 			dev_err(&pdev->dev,
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 5/6] serial: 8250_bcm2835aux: Use generic remapping code
  2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
                   ` (3 preceding siblings ...)
  2020-01-16 12:14 ` [PATCH 4/6] serial: 8250_bcm2835aux: Allocate uart_8250_port on stack Lukas Wunner
@ 2020-01-16 12:14 ` Lukas Wunner
  2020-01-16 12:14 ` [PATCH 6/6] serial: 8250_bcm2835aux: Document struct bcm2835aux_data Lukas Wunner
  2020-01-16 16:11 ` [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Nicolas Saenz Julienne
  6 siblings, 0 replies; 12+ messages in thread
From: Lukas Wunner @ 2020-01-16 12:14 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Jiri Slaby, Nicolas Saenz Julienne, linux-serial,
	linux-rpi-kernel, Martin Sperl

On probe the bcm2835aux UART driver misreports the register base address
as 0x0:

ttyS0 at MMIO 0x0 (irq = 53, base_baud = 50000000) is a 16550

That's because the driver remaps the registers itself.  Take advantage
of the generic remapping code in serial8250_request_std_resource() to
get a message with the correct address and to simplify the driver.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index f03d38e7c3a7..d21460c9ef4b 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -41,7 +41,7 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	up.port.iotype = UPIO_MEM;
 	up.port.fifosize = 8;
 	up.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE |
-			UPF_SKIP_TEST;
+			UPF_SKIP_TEST | UPF_IOREMAP;
 
 	/* get the clock - this also enables the HW */
 	data->clk = devm_clk_get(&pdev->dev, NULL);
@@ -64,10 +64,8 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "memory resource not found");
 		return -EINVAL;
 	}
-	up.port.membase = devm_ioremap_resource(&pdev->dev, res);
-	ret = PTR_ERR_OR_ZERO(up.port.membase);
-	if (ret)
-		return ret;
+	up.port.mapbase = res->start;
+	up.port.mapsize = resource_size(res);
 
 	/* Check for a fixed line number */
 	ret = of_alias_get_id(pdev->dev.of_node, "serial");
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 6/6] serial: 8250_bcm2835aux: Document struct bcm2835aux_data
  2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
                   ` (4 preceding siblings ...)
  2020-01-16 12:14 ` [PATCH 5/6] serial: 8250_bcm2835aux: Use generic remapping code Lukas Wunner
@ 2020-01-16 12:14 ` Lukas Wunner
  2020-01-16 13:02   ` Matthias Brugger
  2020-01-16 16:11 ` [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Nicolas Saenz Julienne
  6 siblings, 1 reply; 12+ messages in thread
From: Lukas Wunner @ 2020-01-16 12:14 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Jiri Slaby, Nicolas Saenz Julienne, linux-serial,
	linux-rpi-kernel, Martin Sperl

Document the driver private data of the BCM2835 auxiliary UART so that
upcoming commits may add further members with proper kerneldoc.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index d21460c9ef4b..e70e3cc30050 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -16,6 +16,11 @@
 
 #include "8250.h"
 
+/**
+ * struct bcm2835aux_data - driver private data of BCM2835 auxiliary UART
+ * @clk: clock producer of the port's uartclk
+ * @line: index of the port's serial8250_ports[] entry
+ */
 struct bcm2835aux_data {
 	struct clk *clk;
 	int line;
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* Re: [PATCH 2/6] serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
  2020-01-16 12:14 ` [PATCH 2/6] serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER Lukas Wunner
@ 2020-01-16 12:58   ` Matthias Brugger
  0 siblings, 0 replies; 12+ messages in thread
From: Matthias Brugger @ 2020-01-16 12:58 UTC (permalink / raw)
  To: Lukas Wunner, Greg Kroah-Hartman
  Cc: linux-rpi-kernel, linux-serial, Jiri Slaby



On 16/01/2020 13:14, Lukas Wunner wrote:
> From: Phil Elwell <phil@raspberrypi.org>
> 
> Suppress a gratuitous error message if devm_clk_get() returns
> -EPROBE_DEFER.
> 
> Signed-off-by: Phil Elwell <phil@raspberrypi.org>
> [lukas: extend commit message]
> Signed-off-by: Lukas Wunner <lukas@wunner.de>

Reviewed-by: Matthias Brugger <mbrugger@suse.com>

> ---
>  drivers/tty/serial/8250/8250_bcm2835aux.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
> index 4997c519ebb3..33da68341c3a 100644
> --- a/drivers/tty/serial/8250/8250_bcm2835aux.c
> +++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
> @@ -50,7 +50,8 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
>  	data->clk = devm_clk_get(&pdev->dev, NULL);
>  	ret = PTR_ERR_OR_ZERO(data->clk);
>  	if (ret) {
> -		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(&pdev->dev, "could not get clk: %d\n", ret);
>  		return ret;
>  	}
>  
> 

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH 3/6] serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  2020-01-16 12:14 ` [PATCH 3/6] serial: 8250_bcm2835aux: Suppress register_port " Lukas Wunner
@ 2020-01-16 12:58   ` Matthias Brugger
  0 siblings, 0 replies; 12+ messages in thread
From: Matthias Brugger @ 2020-01-16 12:58 UTC (permalink / raw)
  To: Lukas Wunner, Greg Kroah-Hartman
  Cc: linux-rpi-kernel, linux-serial, Jiri Slaby



On 16/01/2020 13:14, Lukas Wunner wrote:
> Suppress a gratuitous error message if serial8250_register_8250_port()
> returns -EPROBE_DEFER.
> 
> Signed-off-by: Lukas Wunner <lukas@wunner.de>

Reviewed-by: Matthias Brugger <mbrugger@suse.com>

> ---
>  drivers/tty/serial/8250/8250_bcm2835aux.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
> index 33da68341c3a..fb850d0ad643 100644
> --- a/drivers/tty/serial/8250/8250_bcm2835aux.c
> +++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
> @@ -95,8 +95,9 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
>  	/* register the port */
>  	ret = serial8250_register_8250_port(&data->uart);
>  	if (ret < 0) {
> -		dev_err(&pdev->dev, "unable to register 8250 port - %d\n",
> -			ret);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(&pdev->dev,
> +				"unable to register 8250 port - %d\n", ret);
>  		goto dis_clk;
>  	}
>  	data->line = ret;
> 

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH 6/6] serial: 8250_bcm2835aux: Document struct bcm2835aux_data
  2020-01-16 12:14 ` [PATCH 6/6] serial: 8250_bcm2835aux: Document struct bcm2835aux_data Lukas Wunner
@ 2020-01-16 13:02   ` Matthias Brugger
  0 siblings, 0 replies; 12+ messages in thread
From: Matthias Brugger @ 2020-01-16 13:02 UTC (permalink / raw)
  To: Lukas Wunner, Greg Kroah-Hartman
  Cc: linux-rpi-kernel, linux-serial, Jiri Slaby



On 16/01/2020 13:14, Lukas Wunner wrote:
> Document the driver private data of the BCM2835 auxiliary UART so that
> upcoming commits may add further members with proper kerneldoc.
> 
> Signed-off-by: Lukas Wunner <lukas@wunner.de>

Reviewed-by: Matthias Brugger <mbrugger@suse.com>

> ---
>  drivers/tty/serial/8250/8250_bcm2835aux.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
> index d21460c9ef4b..e70e3cc30050 100644
> --- a/drivers/tty/serial/8250/8250_bcm2835aux.c
> +++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
> @@ -16,6 +16,11 @@
>  
>  #include "8250.h"
>  
> +/**
> + * struct bcm2835aux_data - driver private data of BCM2835 auxiliary UART
> + * @clk: clock producer of the port's uartclk
> + * @line: index of the port's serial8250_ports[] entry
> + */
>  struct bcm2835aux_data {
>  	struct clk *clk;
>  	int line;
> 

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH 4/6] serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  2020-01-16 12:14 ` [PATCH 4/6] serial: 8250_bcm2835aux: Allocate uart_8250_port on stack Lukas Wunner
@ 2020-01-16 13:06   ` Matthias Brugger
  0 siblings, 0 replies; 12+ messages in thread
From: Matthias Brugger @ 2020-01-16 13:06 UTC (permalink / raw)
  To: Lukas Wunner, Greg Kroah-Hartman
  Cc: linux-rpi-kernel, linux-serial, Jiri Slaby



On 16/01/2020 13:14, Lukas Wunner wrote:
> The bcm2835aux UART driver stores a struct uart_8250_port in its private
> data even though it's only passed once to serial8250_register_8250_port()
> (which copies all relevant data) and becomes obsolete afterwards.
> Allocate the struct on the stack instead for simplicity and to conserve
> memory.
> 
> The driver also initializes a spinlock in the struct which is never used.
> Drop that as well.
> 
> Signed-off-by: Lukas Wunner <lukas@wunner.de>
> Cc: Martin Sperl <kernel@martin.sperl.org>

Reviewed-by: Matthias Brugger <mbrugger@suse.com>

> ---
>  drivers/tty/serial/8250/8250_bcm2835aux.c | 33 +++++++++++------------
>  1 file changed, 15 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
> index fb850d0ad643..f03d38e7c3a7 100644
> --- a/drivers/tty/serial/8250/8250_bcm2835aux.c
> +++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
> @@ -17,13 +17,13 @@
>  #include "8250.h"
>  
>  struct bcm2835aux_data {
> -	struct uart_8250_port uart;
>  	struct clk *clk;
>  	int line;
>  };
>  
>  static int bcm2835aux_serial_probe(struct platform_device *pdev)
>  {
> +	struct uart_8250_port up = { };
>  	struct bcm2835aux_data *data;
>  	struct resource *res;
>  	int ret;
> @@ -34,17 +34,14 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
>  		return -ENOMEM;
>  
>  	/* initialize data */
> -	spin_lock_init(&data->uart.port.lock);
> -	data->uart.capabilities = UART_CAP_FIFO | UART_CAP_MINI;
> -	data->uart.port.dev = &pdev->dev;
> -	data->uart.port.regshift = 2;
> -	data->uart.port.type = PORT_16550;
> -	data->uart.port.iotype = UPIO_MEM;
> -	data->uart.port.fifosize = 8;
> -	data->uart.port.flags = UPF_SHARE_IRQ |
> -				UPF_FIXED_PORT |
> -				UPF_FIXED_TYPE |
> -				UPF_SKIP_TEST;
> +	up.capabilities = UART_CAP_FIFO | UART_CAP_MINI;
> +	up.port.dev = &pdev->dev;
> +	up.port.regshift = 2;
> +	up.port.type = PORT_16550;
> +	up.port.iotype = UPIO_MEM;
> +	up.port.fifosize = 8;
> +	up.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE |
> +			UPF_SKIP_TEST;
>  
>  	/* get the clock - this also enables the HW */
>  	data->clk = devm_clk_get(&pdev->dev, NULL);
> @@ -59,7 +56,7 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
>  	ret = platform_get_irq(pdev, 0);
>  	if (ret < 0)
>  		return ret;
> -	data->uart.port.irq = ret;
> +	up.port.irq = ret;
>  
>  	/* map the main registers */
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> @@ -67,15 +64,15 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
>  		dev_err(&pdev->dev, "memory resource not found");
>  		return -EINVAL;
>  	}
> -	data->uart.port.membase = devm_ioremap_resource(&pdev->dev, res);
> -	ret = PTR_ERR_OR_ZERO(data->uart.port.membase);
> +	up.port.membase = devm_ioremap_resource(&pdev->dev, res);
> +	ret = PTR_ERR_OR_ZERO(up.port.membase);
>  	if (ret)
>  		return ret;
>  
>  	/* Check for a fixed line number */
>  	ret = of_alias_get_id(pdev->dev.of_node, "serial");
>  	if (ret >= 0)
> -		data->uart.port.line = ret;
> +		up.port.line = ret;
>  
>  	/* enable the clock as a last step */
>  	ret = clk_prepare_enable(data->clk);
> @@ -90,10 +87,10 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
>  	 * so we have to multiply the actual clock by 2
>  	 * to get identical baudrates.
>  	 */
> -	data->uart.port.uartclk = clk_get_rate(data->clk) * 2;
> +	up.port.uartclk = clk_get_rate(data->clk) * 2;
>  
>  	/* register the port */
> -	ret = serial8250_register_8250_port(&data->uart);
> +	ret = serial8250_register_8250_port(&up);
>  	if (ret < 0) {
>  		if (ret != -EPROBE_DEFER)
>  			dev_err(&pdev->dev,
> 

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups
  2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
                   ` (5 preceding siblings ...)
  2020-01-16 12:14 ` [PATCH 6/6] serial: 8250_bcm2835aux: Document struct bcm2835aux_data Lukas Wunner
@ 2020-01-16 16:11 ` Nicolas Saenz Julienne
  6 siblings, 0 replies; 12+ messages in thread
From: Nicolas Saenz Julienne @ 2020-01-16 16:11 UTC (permalink / raw)
  To: Lukas Wunner, Greg Kroah-Hartman
  Cc: Jiri Slaby, linux-serial, linux-rpi-kernel, Martin Sperl, Phil Elwell

[-- Attachment #1: Type: text/plain, Size: 1010 bytes --]

Hi Lukas,

On Thu, 2020-01-16 at 13:14 +0100, Lukas Wunner wrote:
> Here's a collection of fixes & cleanups for the Raspberry Pi auxiliary UART
> to prepare for upcoming feature work on the driver.
> 
> With compliments from Revolution Pi labs (https://revolution.kunbus.com/).
> 
> Lukas Wunner (5):
>   serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
>   serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
>   serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
>   serial: 8250_bcm2835aux: Use generic remapping code
>   serial: 8250_bcm2835aux: Document struct bcm2835aux_data
> 
> Phil Elwell (1):
>   serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
> 
>  drivers/tty/serial/8250/8250_bcm2835aux.c | 50 ++++++++++++-----------
>  1 file changed, 26 insertions(+), 24 deletions(-)
> 

Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

Thanks!
Nicolas


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^ permalink raw reply	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2020-01-16 16:11 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-01-16 12:14 [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Lukas Wunner
2020-01-16 12:14 ` [PATCH 1/6] serial: 8250_bcm2835aux: Fix line mismatch on driver unbind Lukas Wunner
2020-01-16 12:14 ` [PATCH 2/6] serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER Lukas Wunner
2020-01-16 12:58   ` Matthias Brugger
2020-01-16 12:14 ` [PATCH 3/6] serial: 8250_bcm2835aux: Suppress register_port " Lukas Wunner
2020-01-16 12:58   ` Matthias Brugger
2020-01-16 12:14 ` [PATCH 4/6] serial: 8250_bcm2835aux: Allocate uart_8250_port on stack Lukas Wunner
2020-01-16 13:06   ` Matthias Brugger
2020-01-16 12:14 ` [PATCH 5/6] serial: 8250_bcm2835aux: Use generic remapping code Lukas Wunner
2020-01-16 12:14 ` [PATCH 6/6] serial: 8250_bcm2835aux: Document struct bcm2835aux_data Lukas Wunner
2020-01-16 13:02   ` Matthias Brugger
2020-01-16 16:11 ` [PATCH 0/6] Raspberry Pi auxiliary UART fixes & cleanups Nicolas Saenz Julienne

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