* [PATCH 0/4] switch arc-uart to devicetree based probing
@ 2013-01-11 6:20 Vineet Gupta
2013-01-11 6:20 ` [PATCH 1/4] serial/arc-uart: Don't index with -ve platform_device->id Vineet Gupta
` (4 more replies)
0 siblings, 5 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-01-11 6:20 UTC (permalink / raw)
To: linux-serial, linux-kernel; +Cc: Vineet Gupta
Hi,
As part of converting ARC Port to devicetree infrastructure, the following
series converts the arc-uart driver to DT.
* The first patch is a bug-fix which showed up in the process as DT based
platform devices by default have -ve id
* Next two prepare the driver for forthcoming DT changes.
* Last one contains the DT bindings and driver using those.
Couple of points worth mentioning:
* The earlyprintk portion of driver still relies on static platform data
we would need some earlyprintk handling in of_fdt_* to clean it up properly
* Two of the three platform data instances are now retrieved from DT.
However one still needs to be dynamically passed by platform (using
of_dev_auxdata) as we want to run same image in simulator and hardware
Tested on in-works ARC 3.8 port.
P.S. Greg, can this be treated as a bug-fix for 3.8
Thx,
-Vineet
Vineet Gupta (4):
serial/arc-uart: Don't index with -ve platform_device->id
serial/arc-uart: split probe from probe_earlyprintk
serial/arc-uart: platform_data order changed
serial/arc-uart: switch to devicetree based probing
.../devicetree/bindings/tty/serial/arc-uart.txt | 26 ++++++
drivers/tty/serial/arc_uart.c | 95 ++++++++++++++------
2 files changed, 94 insertions(+), 27 deletions(-)
create mode 100644 Documentation/devicetree/bindings/tty/serial/arc-uart.txt
--
1.7.4.1
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH 1/4] serial/arc-uart: Don't index with -ve platform_device->id
2013-01-11 6:20 [PATCH 0/4] switch arc-uart to devicetree based probing Vineet Gupta
@ 2013-01-11 6:20 ` Vineet Gupta
2013-01-11 6:20 ` [PATCH 2/4] serial/arc-uart: split probe from probe_earlyprintk Vineet Gupta
` (3 subsequent siblings)
4 siblings, 0 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-01-11 6:20 UTC (permalink / raw)
To: linux-serial, linux-kernel
Cc: Vineet Gupta, Alan Cox, Greg Kroah-Hartman, Jiri Slaby
probe routine could index into port[] with -ve index. The check in
arc_uart_init_one() was too late.
This came to light when trying to port driver to CONFIG_OF, where
bydefault of-core code sets -ve platform dev id and in absence of
DT serial aliases, driver would use the -ve index.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
---
drivers/tty/serial/arc_uart.c | 29 +++++++++++++++--------------
1 files changed, 15 insertions(+), 14 deletions(-)
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 3e0b3fa..8089dc3 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -526,15 +526,11 @@ static struct uart_ops arc_serial_pops = {
};
static int
-arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
+arc_uart_init_one(struct platform_device *pdev, int dev_id)
{
struct resource *res, *res2;
unsigned long *plat_data;
-
- if (pdev->id < 0 || pdev->id >= CONFIG_SERIAL_ARC_NR_PORTS) {
- dev_err(&pdev->dev, "Wrong uart platform device id.\n");
- return -ENOENT;
- }
+ struct arc_uart_port *uart = &arc_uart_ports[dev_id];
plat_data = ((unsigned long *)(pdev->dev.platform_data));
uart->baud = plat_data[0];
@@ -557,7 +553,7 @@ arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
uart->port.dev = &pdev->dev;
uart->port.iotype = UPIO_MEM;
uart->port.flags = UPF_BOOT_AUTOCONF;
- uart->port.line = pdev->id;
+ uart->port.line = dev_id;
uart->port.ops = &arc_serial_pops;
uart->port.uartclk = plat_data[1];
@@ -657,9 +653,14 @@ static struct __initdata console arc_early_serial_console = {
static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
{
- arc_early_serial_console.index = pdev->id;
+ int dev_id = pdev->id < 0 ? 0 : pdev->id;
+ int rc;
- arc_uart_init_one(pdev, &arc_uart_ports[pdev->id]);
+ arc_early_serial_console.index = dev_id;
+
+ rc = arc_uart_init_one(pdev, dev_id);
+ if (rc)
+ panic("early console init failed\n");
arc_serial_console_setup(&arc_early_serial_console, NULL);
@@ -675,18 +676,18 @@ static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
static int arc_serial_probe(struct platform_device *pdev)
{
- struct arc_uart_port *uart;
- int rc;
+ int rc, dev_id;
if (is_early_platform_device(pdev))
return arc_serial_probe_earlyprintk(pdev);
- uart = &arc_uart_ports[pdev->id];
- rc = arc_uart_init_one(pdev, uart);
+ dev_id = pdev->id < 0 ? 0 : pdev->id;
+ rc = arc_uart_init_one(pdev, dev_id);
if (rc)
return rc;
- return uart_add_one_port(&arc_uart_driver, &uart->port);
+ rc = uart_add_one_port(&arc_uart_driver, &arc_uart_ports[dev_id].port);
+ return rc;
}
static int arc_serial_remove(struct platform_device *pdev)
--
1.7.4.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH 2/4] serial/arc-uart: split probe from probe_earlyprintk
2013-01-11 6:20 [PATCH 0/4] switch arc-uart to devicetree based probing Vineet Gupta
2013-01-11 6:20 ` [PATCH 1/4] serial/arc-uart: Don't index with -ve platform_device->id Vineet Gupta
@ 2013-01-11 6:20 ` Vineet Gupta
2013-01-11 6:20 ` [PATCH 3/4] serial/arc-uart: platform_data order changed Vineet Gupta
` (2 subsequent siblings)
4 siblings, 0 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-01-11 6:20 UTC (permalink / raw)
To: linux-serial, linux-kernel
Cc: Vineet Gupta, Alan Cox, Greg Kroah-Hartman, Jiri Slaby
This is in preparation for devicetree based probing, where earlyprintk
won't have access to DT serial aliases which the normal probe would
absolutely rely on.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
---
drivers/tty/serial/arc_uart.c | 21 +++++++++++----------
1 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 8089dc3..9de26ba 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -651,7 +651,7 @@ static struct __initdata console arc_early_serial_console = {
.index = -1
};
-static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
+static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev)
{
int dev_id = pdev->id < 0 ? 0 : pdev->id;
int rc;
@@ -667,20 +667,12 @@ static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
register_console(&arc_early_serial_console);
return 0;
}
-#else
-static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
-{
- return -ENODEV;
-}
#endif /* CONFIG_SERIAL_ARC_CONSOLE */
static int arc_serial_probe(struct platform_device *pdev)
{
int rc, dev_id;
- if (is_early_platform_device(pdev))
- return arc_serial_probe_earlyprintk(pdev);
-
dev_id = pdev->id < 0 ? 0 : pdev->id;
rc = arc_uart_init_one(pdev, dev_id);
if (rc)
@@ -706,6 +698,15 @@ static struct platform_driver arc_platform_driver = {
};
#ifdef CONFIG_SERIAL_ARC_CONSOLE
+
+static struct platform_driver early_arc_platform_driver = {
+ .probe = arc_serial_probe_earlyprintk,
+ .remove = arc_serial_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ },
+};
/*
* Register an early platform driver of "earlyprintk" class.
* ARCH platform code installs the driver and probes the early devices
@@ -713,7 +714,7 @@ static struct platform_driver arc_platform_driver = {
* or it could be done independently, for all "earlyprintk" class drivers.
* [see arch/arc/plat-arcfpga/platform.c]
*/
-early_platform_init("earlyprintk", &arc_platform_driver);
+early_platform_init("earlyprintk", &early_arc_platform_driver);
#endif /* CONFIG_SERIAL_ARC_CONSOLE */
--
1.7.4.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH 3/4] serial/arc-uart: platform_data order changed
2013-01-11 6:20 [PATCH 0/4] switch arc-uart to devicetree based probing Vineet Gupta
2013-01-11 6:20 ` [PATCH 1/4] serial/arc-uart: Don't index with -ve platform_device->id Vineet Gupta
2013-01-11 6:20 ` [PATCH 2/4] serial/arc-uart: split probe from probe_earlyprintk Vineet Gupta
@ 2013-01-11 6:20 ` Vineet Gupta
2013-01-11 6:20 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Vineet Gupta
2013-01-16 6:16 ` [PATCH 0/4] switch arc-uart " Greg KH
4 siblings, 0 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-01-11 6:20 UTC (permalink / raw)
To: linux-serial, linux-kernel
Cc: Vineet Gupta, Alan Cox, Greg Kroah-Hartman, Jiri Slaby
* is_emulated is now 1st element, rather than last
* also tucked all platform data refs together
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
---
drivers/tty/serial/arc_uart.c | 11 ++++++-----
1 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 9de26ba..2db6410 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -533,7 +533,12 @@ arc_uart_init_one(struct platform_device *pdev, int dev_id)
struct arc_uart_port *uart = &arc_uart_ports[dev_id];
plat_data = ((unsigned long *)(pdev->dev.platform_data));
- uart->baud = plat_data[0];
+ if (!plat_data)
+ return -ENODEV;
+
+ uart->is_emulated = !!plat_data[0]; /* workaround ISS bug */
+ uart->port.uartclk = plat_data[1];
+ uart->baud = plat_data[2];
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
@@ -556,7 +561,6 @@ arc_uart_init_one(struct platform_device *pdev, int dev_id)
uart->port.line = dev_id;
uart->port.ops = &arc_serial_pops;
- uart->port.uartclk = plat_data[1];
uart->port.fifosize = ARC_UART_TX_FIFO_SIZE;
/*
@@ -565,9 +569,6 @@ arc_uart_init_one(struct platform_device *pdev, int dev_id)
*/
uart->port.ignore_status_mask = 0;
- /* Real Hardware vs. emulated to work around a bug */
- uart->is_emulated = !!plat_data[2];
-
return 0;
}
--
1.7.4.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-01-11 6:20 [PATCH 0/4] switch arc-uart to devicetree based probing Vineet Gupta
` (2 preceding siblings ...)
2013-01-11 6:20 ` [PATCH 3/4] serial/arc-uart: platform_data order changed Vineet Gupta
@ 2013-01-11 6:20 ` Vineet Gupta
2013-01-11 11:33 ` Arnd Bergmann
2013-02-08 23:01 ` Grant Likely
2013-01-16 6:16 ` [PATCH 0/4] switch arc-uart " Greg KH
4 siblings, 2 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-01-11 6:20 UTC (permalink / raw)
To: linux-serial, linux-kernel
Cc: Vineet Gupta, Grant Likely, Arnd Bergmann, Alan Cox,
Greg Kroah-Hartman, devicetree-discuss, Rob Herring, Rob Landley
* DT binding for arc-uart
* With alll the bits in place we can now use DT probing.
Note that there's a bit of kludge right now because earlyprintk portion
of driver can't use the DT infrastrcuture to get resoures/plat_data.
This requires some infrastructre changes to of_flat_ framework
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-serial@vger.kernel.org
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: linux-serial@vger.kernel.org
---
.../devicetree/bindings/tty/serial/arc-uart.txt | 26 ++++++++++++
drivers/tty/serial/arc_uart.c | 43 ++++++++++++++++++-
2 files changed, 66 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/tty/serial/arc-uart.txt
diff --git a/Documentation/devicetree/bindings/tty/serial/arc-uart.txt b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt
new file mode 100644
index 0000000..c3bd8f9
--- /dev/null
+++ b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt
@@ -0,0 +1,26 @@
+* Synopsys ARC UART : Non standard UART used in some of the ARC FPGA boards
+
+Required properties:
+- compatible : "snps,arc-uart"
+- reg : offset and length of the register set for the device.
+- interrupts : device interrupt
+- clock-frequency : the input clock frequency for the UART
+- baud : baud rate for UART
+
+e.g.
+
+arcuart0: serial@c0fc1000 {
+ compatible = "snps,arc-uart";
+ reg = <0xc0fc1000 0x100>;
+ interrupts = <5>;
+ clock-frequency = <80000000>;
+ baud = <115200>;
+ status = "okay";
+};
+
+Note: Each port should have an alias correctly numbered in "aliases" node.
+
+e.g.
+aliases {
+ serial0 = &arcuart0;
+};
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 2db6410..b468601 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -37,6 +37,8 @@
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
/*************************************
* ARC UART Hardware Specs
@@ -537,8 +539,26 @@ arc_uart_init_one(struct platform_device *pdev, int dev_id)
return -ENODEV;
uart->is_emulated = !!plat_data[0]; /* workaround ISS bug */
- uart->port.uartclk = plat_data[1];
- uart->baud = plat_data[2];
+
+ if (is_early_platform_device(pdev)) {
+ uart->port.uartclk = plat_data[1];
+ uart->baud = plat_data[2];
+ } else {
+ struct device_node *np = pdev->dev.of_node;
+ u32 val;
+
+ if (of_property_read_u32(np, "clock-frequency", &val)) {
+ dev_err(&pdev->dev, "clock-frequency property NOTset\n");
+ return -EINVAL;
+ }
+ uart->port.uartclk = val;
+
+ if (of_property_read_u32(np, "baud", &val)) {
+ dev_err(&pdev->dev, "baud property NOT set\n");
+ return -EINVAL;
+ }
+ uart->baud = val;
+ }
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
@@ -673,8 +693,18 @@ static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev)
static int arc_serial_probe(struct platform_device *pdev)
{
int rc, dev_id;
+ struct device_node *np = pdev->dev.of_node;
+
+ /* no device tree device */
+ if (!np)
+ return -ENODEV;
+
+ dev_id = of_alias_get_id(np, "serial");
+ if (dev_id < 0) {
+ dev_err(&pdev->dev, "failed to get alias id: %d\n", dev_id);
+ return dev_id;
+ }
- dev_id = pdev->id < 0 ? 0 : pdev->id;
rc = arc_uart_init_one(pdev, dev_id);
if (rc)
return rc;
@@ -689,12 +719,19 @@ static int arc_serial_remove(struct platform_device *pdev)
return 0;
}
+static const struct of_device_id arc_uart_dt_ids[] = {
+ { .compatible = "snps,arc-uart" },
+ { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, arc_uart_dt_ids);
+
static struct platform_driver arc_platform_driver = {
.probe = arc_serial_probe,
.remove = arc_serial_remove,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
+ .of_match_table = arc_uart_dt_ids,
},
};
--
1.7.4.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* Re: [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-01-11 6:20 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Vineet Gupta
@ 2013-01-11 11:33 ` Arnd Bergmann
2013-01-11 11:55 ` Vineet Gupta
2013-02-08 23:01 ` Grant Likely
1 sibling, 1 reply; 15+ messages in thread
From: Arnd Bergmann @ 2013-01-11 11:33 UTC (permalink / raw)
To: Vineet Gupta
Cc: linux-serial, linux-kernel, Grant Likely, Alan Cox,
Greg Kroah-Hartman, devicetree-discuss, Rob Herring, Rob Landley
On Friday 11 January 2013, Vineet Gupta wrote:
> * DT binding for arc-uart
> * With alll the bits in place we can now use DT probing.
>
> Note that there's a bit of kludge right now because earlyprintk portion
> of driver can't use the DT infrastrcuture to get resoures/plat_data.
> This requires some infrastructre changes to of_flat_ framework
>
> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
> Cc: Grant Likely <grant.likely@secretlab.ca>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: linux-serial@vger.kernel.org
> Cc: Alan Cox <alan@linux.intel.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: devicetree-discuss@lists.ozlabs.org
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: Rob Landley <rob@landley.net>
> Cc: linux-serial@vger.kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Quick question about the name though: is this UART only used
on ARC, or is it something that synopsys licenses to other
parties as well? If the latter is true, we might want to
add a more generic "compatible" value for those that use
it on another architecture.
Arnd
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-01-11 11:33 ` Arnd Bergmann
@ 2013-01-11 11:55 ` Vineet Gupta
2013-01-11 20:17 ` Arnd Bergmann
0 siblings, 1 reply; 15+ messages in thread
From: Vineet Gupta @ 2013-01-11 11:55 UTC (permalink / raw)
To: Arnd Bergmann
Cc: linux-serial, linux-kernel, Grant Likely, Alan Cox,
Greg Kroah-Hartman, devicetree-discuss, Rob Herring, Rob Landley
On Friday 11 January 2013 05:03 PM, Arnd Bergmann wrote:
> On Friday 11 January 2013, Vineet Gupta wrote:
>> * DT binding for arc-uart
>> * With alll the bits in place we can now use DT probing.
>>
>> Note that there's a bit of kludge right now because earlyprintk portion
>> of driver can't use the DT infrastrcuture to get resoures/plat_data.
>> This requires some infrastructre changes to of_flat_ framework
>>
>> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
>> Cc: Grant Likely <grant.likely@secretlab.ca>
>> Cc: Arnd Bergmann <arnd@arndb.de>
>> Cc: linux-serial@vger.kernel.org
>> Cc: Alan Cox <alan@linux.intel.com>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: devicetree-discuss@lists.ozlabs.org
>> Cc: Rob Herring <rob.herring@calxeda.com>
>> Cc: Rob Landley <rob@landley.net>
>> Cc: linux-serial@vger.kernel.org
> Acked-by: Arnd Bergmann <arnd@arndb.de>
>
> Quick question about the name though: is this UART only used
> on ARC, or is it something that synopsys licenses to other
> parties as well? If the latter is true, we might want to
> add a more generic "compatible" value for those that use
> it on another architecture.
It's not licensed as standalone IP - since its not a standard 8250. It is only
(but actively) used on the internal FPGA flows from ARC days.
Thx,
Vineet
> Arnd
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-01-11 11:55 ` Vineet Gupta
@ 2013-01-11 20:17 ` Arnd Bergmann
0 siblings, 0 replies; 15+ messages in thread
From: Arnd Bergmann @ 2013-01-11 20:17 UTC (permalink / raw)
To: Vineet Gupta
Cc: linux-serial, linux-kernel, Grant Likely, Alan Cox,
Greg Kroah-Hartman, devicetree-discuss, Rob Herring, Rob Landley
On Friday 11 January 2013, Vineet Gupta wrote:
> On Friday 11 January 2013 05:03 PM, Arnd Bergmann wrote:
> > Quick question about the name though: is this UART only used
> > on ARC, or is it something that synopsys licenses to other
> > parties as well? If the latter is true, we might want to
> > add a more generic "compatible" value for those that use
> > it on another architecture.
>
> It's not licensed as standalone IP - since its not a standard 8250. It is only
> (but actively) used on the internal FPGA flows from ARC days.
>
Ok, thanks for the confirmation.
Arnd
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH 0/4] switch arc-uart to devicetree based probing
2013-01-11 6:20 [PATCH 0/4] switch arc-uart to devicetree based probing Vineet Gupta
` (3 preceding siblings ...)
2013-01-11 6:20 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Vineet Gupta
@ 2013-01-16 6:16 ` Greg KH
2013-01-16 6:16 ` Vineet Gupta
4 siblings, 1 reply; 15+ messages in thread
From: Greg KH @ 2013-01-16 6:16 UTC (permalink / raw)
To: Vineet Gupta; +Cc: linux-serial, linux-kernel
On Fri, Jan 11, 2013 at 11:50:19AM +0530, Vineet Gupta wrote:
> Hi,
>
> As part of converting ARC Port to devicetree infrastructure, the following
> series converts the arc-uart driver to DT.
>
> * The first patch is a bug-fix which showed up in the process as DT based
> platform devices by default have -ve id
> * Next two prepare the driver for forthcoming DT changes.
> * Last one contains the DT bindings and driver using those.
>
> Couple of points worth mentioning:
> * The earlyprintk portion of driver still relies on static platform data
> we would need some earlyprintk handling in of_fdt_* to clean it up properly
> * Two of the three platform data instances are now retrieved from DT.
> However one still needs to be dynamically passed by platform (using
> of_dev_auxdata) as we want to run same image in simulator and hardware
>
> Tested on in-works ARC 3.8 port.
>
> P.S. Greg, can this be treated as a bug-fix for 3.8
No, because it is not a bugfix, but a new feature, sorry.
greg k-h
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH 0/4] switch arc-uart to devicetree based probing
2013-01-16 6:16 ` [PATCH 0/4] switch arc-uart " Greg KH
@ 2013-01-16 6:16 ` Vineet Gupta
0 siblings, 0 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-01-16 6:16 UTC (permalink / raw)
To: Greg KH; +Cc: linux-serial, linux-kernel
On Wednesday 16 January 2013 11:46 AM, Greg KH wrote:
> On Fri, Jan 11, 2013 at 11:50:19AM +0530, Vineet Gupta wrote:
>> Hi,
>>
>> As part of converting ARC Port to devicetree infrastructure, the following
>> series converts the arc-uart driver to DT.
>>
>> * The first patch is a bug-fix which showed up in the process as DT based
>> platform devices by default have -ve id
>> * Next two prepare the driver for forthcoming DT changes.
>> * Last one contains the DT bindings and driver using those.
>>
>> Couple of points worth mentioning:
>> * The earlyprintk portion of driver still relies on static platform data
>> we would need some earlyprintk handling in of_fdt_* to clean it up properly
>> * Two of the three platform data instances are now retrieved from DT.
>> However one still needs to be dynamically passed by platform (using
>> of_dev_auxdata) as we want to run same image in simulator and hardware
>>
>> Tested on in-works ARC 3.8 port.
>>
>> P.S. Greg, can this be treated as a bug-fix for 3.8
> No, because it is not a bugfix, but a new feature, sorry.
>
> greg k-h
NP. Thx a bunch for merging these.
-Vineet
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-01-11 6:20 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Vineet Gupta
2013-01-11 11:33 ` Arnd Bergmann
@ 2013-02-08 23:01 ` Grant Likely
2013-02-09 6:45 ` Vineet Gupta
1 sibling, 1 reply; 15+ messages in thread
From: Grant Likely @ 2013-02-08 23:01 UTC (permalink / raw)
To: Vineet Gupta, linux-serial, linux-kernel
Cc: Vineet Gupta, Arnd Bergmann, Alan Cox, Greg Kroah-Hartman,
devicetree-discuss, Rob Herring, Rob Landley
On Fri, 11 Jan 2013 11:50:23 +0530, Vineet Gupta <Vineet.Gupta1@synopsys.com> wrote:
> * DT binding for arc-uart
> * With alll the bits in place we can now use DT probing.
>
> Note that there's a bit of kludge right now because earlyprintk portion
> of driver can't use the DT infrastrcuture to get resoures/plat_data.
> This requires some infrastructre changes to of_flat_ framework
>
> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
> Cc: Grant Likely <grant.likely@secretlab.ca>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: linux-serial@vger.kernel.org
> Cc: Alan Cox <alan@linux.intel.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: devicetree-discuss@lists.ozlabs.org
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: Rob Landley <rob@landley.net>
> Cc: linux-serial@vger.kernel.org
> ---
> .../devicetree/bindings/tty/serial/arc-uart.txt | 26 ++++++++++++
> drivers/tty/serial/arc_uart.c | 43 ++++++++++++++++++-
> 2 files changed, 66 insertions(+), 3 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/tty/serial/arc-uart.txt
>
> diff --git a/Documentation/devicetree/bindings/tty/serial/arc-uart.txt b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt
> new file mode 100644
> index 0000000..c3bd8f9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt
> @@ -0,0 +1,26 @@
> +* Synopsys ARC UART : Non standard UART used in some of the ARC FPGA boards
> +
> +Required properties:
> +- compatible : "snps,arc-uart"
> +- reg : offset and length of the register set for the device.
> +- interrupts : device interrupt
> +- clock-frequency : the input clock frequency for the UART
> +- baud : baud rate for UART
change 'baud' to 'current-speed'. There is already precedence for this
with other serial devices.
g.
> @@ -673,8 +693,18 @@ static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev)
> static int arc_serial_probe(struct platform_device *pdev)
> {
> int rc, dev_id;
> + struct device_node *np = pdev->dev.of_node;
> +
> + /* no device tree device */
> + if (!np)
> + return -ENODEV;
This breaks non-DT users. Is this what you intend? It creates a flag day
where users have to switch from non-DT to DT cold-turkey.
> + dev_id = of_alias_get_id(np, "serial");
> + if (dev_id < 0) {
> + dev_err(&pdev->dev, "failed to get alias id: %d\n", dev_id);
> + return dev_id;
> + }
Don't fail on this. If you can't get an id then choose one dynamically.
>
> - dev_id = pdev->id < 0 ? 0 : pdev->id;
> rc = arc_uart_init_one(pdev, dev_id);
> if (rc)
> return rc;
> @@ -689,12 +719,19 @@ static int arc_serial_remove(struct platform_device *pdev)
> return 0;
> }
>
> +static const struct of_device_id arc_uart_dt_ids[] = {
> + { .compatible = "snps,arc-uart" },
> + { /* Sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, arc_uart_dt_ids);
> +
> static struct platform_driver arc_platform_driver = {
> .probe = arc_serial_probe,
> .remove = arc_serial_remove,
> .driver = {
> .name = DRIVER_NAME,
> .owner = THIS_MODULE,
> + .of_match_table = arc_uart_dt_ids,
> },
> };
>
> --
> 1.7.4.1
>
--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-02-08 23:01 ` Grant Likely
@ 2013-02-09 6:45 ` Vineet Gupta
2013-02-09 9:28 ` Arnd Bergmann
2013-02-13 20:47 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Grant Likely
0 siblings, 2 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-02-09 6:45 UTC (permalink / raw)
To: Grant Likely
Cc: linux-serial, linux-kernel, Arnd Bergmann, Greg Kroah-Hartman,
devicetree-discuss, Rob Herring, Rob Landley
On Saturday 09 February 2013 04:31 AM, Grant Likely wrote:
> On Fri, 11 Jan 2013 11:50:23 +0530, Vineet Gupta <Vineet.Gupta1@synopsys.com> wrote:
>> +- clock-frequency : the input clock frequency for the UART
>> +- baud : baud rate for UART
> change 'baud' to 'current-speed'. There is already precedence for this
> with other serial devices.
While I'm OK with this - I can only see of_serial.c following the rule :-)
More importantly I'm not clear about the logistics of this fix. Obviously this has
a bearing on DT files in arch/arc/boot/*. So are such changes (platform + driver)
routed thru the subsystem tree or the arch tree or bits from both with
bisectability not considered - which feels wrong. We have to also consider the
fact that Greg has closed the tty/serial for 3.9. So while I have no objection to
your comment, it seems that the it needs to wait till 3.9-rc1 - or is there an
alternate way.
>
>> @@ -673,8 +693,18 @@ static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev)
>> static int arc_serial_probe(struct platform_device *pdev)
>> {
>> int rc, dev_id;
>> + struct device_node *np = pdev->dev.of_node;
>> +
>> + /* no device tree device */
>> + if (!np)
>> + return -ENODEV;
> This breaks non-DT users. Is this what you intend? It creates a flag day
> where users have to switch from non-DT to DT cold-turkey.
Not supporting non-DT user was not the idea - it just simplifies the code a bit
given that it would only even be runtime used in a ARC Linux port based platform -
which unconditionally enables OF. Further - the ARC port itself is not yet
upstream so there are no "official" user of this in tree driver.
FWIW, ARC Linux port was recently reviewed on lkml/arch mailing lists and is now
in linux-next for a possible 3.9 merge.
>> + dev_id = of_alias_get_id(np, "serial");
>> + if (dev_id < 0) {
>> + dev_err(&pdev->dev, "failed to get alias id: %d\n", dev_id);
>> + return dev_id;
>> + }
> Don't fail on this. If you can't get an id then choose one dynamically.
You mean just assume 0.
Thanks for reviewing.
-Vineet
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-02-09 6:45 ` Vineet Gupta
@ 2013-02-09 9:28 ` Arnd Bergmann
[not found] ` <1360572101-12744-1-git-send-email-vgupta@synopsys.com>
2013-02-13 20:47 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Grant Likely
1 sibling, 1 reply; 15+ messages in thread
From: Arnd Bergmann @ 2013-02-09 9:28 UTC (permalink / raw)
To: Vineet Gupta
Cc: Grant Likely, linux-serial, linux-kernel, Greg Kroah-Hartman,
devicetree-discuss, Rob Herring, Rob Landley
On Saturday 09 February 2013, Vineet Gupta wrote:
> On Saturday 09 February 2013 04:31 AM, Grant Likely wrote:
> > On Fri, 11 Jan 2013 11:50:23 +0530, Vineet Gupta <Vineet.Gupta1@synopsys.com> wrote:
> >> +- clock-frequency : the input clock frequency for the UART
> >> +- baud : baud rate for UART
> > change 'baud' to 'current-speed'. There is already precedence for this
> > with other serial devices.
>
> While I'm OK with this - I can only see of_serial.c following the rule :-)
> More importantly I'm not clear about the logistics of this fix. Obviously this has
> a bearing on DT files in arch/arc/boot/*. So are such changes (platform + driver)
> routed thru the subsystem tree or the arch tree or bits from both with
> bisectability not considered - which feels wrong. We have to also consider the
> fact that Greg has closed the tty/serial for 3.9. So while I have no objection to
> your comment, it seems that the it needs to wait till 3.9-rc1 - or is there an
> alternate way.
I'd consider this one a bug fix, so while Greg is not accepting any new
features for the serial tree, I think it should still get in that way
and should not be controversial as an add-on change.
Arnd
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH] serial/arc-uart: Miscll DT related updates (Grant's review comments)
[not found] ` <1360572101-12744-1-git-send-email-vgupta@synopsys.com>
@ 2013-02-11 8:41 ` Vineet Gupta
0 siblings, 0 replies; 15+ messages in thread
From: Vineet Gupta @ 2013-02-11 8:41 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Grant Likely, Arnd Bergmann, linux-serial, Vineet Gupta,
devicetree-discuss, Rob Herring, Rob Landley, linux-kernel
-replace "baud" with "current-speed"
-if uart alias doesn't exist in DT, don't abort, pick 0
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
.../devicetree/bindings/tty/serial/arc-uart.txt | 4 ++--
drivers/tty/serial/arc_uart.c | 10 ++++------
2 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/Documentation/devicetree/bindings/tty/serial/arc-uart.txt b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt
index c3bd8f9..5cae2eb 100644
--- a/Documentation/devicetree/bindings/tty/serial/arc-uart.txt
+++ b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt
@@ -5,7 +5,7 @@ Required properties:
- reg : offset and length of the register set for the device.
- interrupts : device interrupt
- clock-frequency : the input clock frequency for the UART
-- baud : baud rate for UART
+- current-speed : baud rate for UART
e.g.
@@ -14,7 +14,7 @@ arcuart0: serial@c0fc1000 {
reg = <0xc0fc1000 0x100>;
interrupts = <5>;
clock-frequency = <80000000>;
- baud = <115200>;
+ current-speed = <115200>;
status = "okay";
};
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 6f7eadc..d97e194 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -547,8 +547,8 @@ arc_uart_init_one(struct platform_device *pdev, int dev_id)
}
uart->port.uartclk = val;
- if (of_property_read_u32(np, "baud", &val)) {
- dev_err(&pdev->dev, "baud property NOT set\n");
+ if (of_property_read_u32(np, "current-speed", &val)) {
+ dev_err(&pdev->dev, "current-speed property NOT set\n");
return -EINVAL;
}
uart->baud = val;
@@ -694,10 +694,8 @@ static int arc_serial_probe(struct platform_device *pdev)
return -ENODEV;
dev_id = of_alias_get_id(np, "serial");
- if (dev_id < 0) {
- dev_err(&pdev->dev, "failed to get alias id: %d\n", dev_id);
- return dev_id;
- }
+ if (dev_id < 0)
+ dev_id = 0;
rc = arc_uart_init_one(pdev, dev_id);
if (rc)
--
1.7.4.1
^ permalink raw reply related [flat|nested] 15+ messages in thread
* Re: [PATCH 4/4] serial/arc-uart: switch to devicetree based probing
2013-02-09 6:45 ` Vineet Gupta
2013-02-09 9:28 ` Arnd Bergmann
@ 2013-02-13 20:47 ` Grant Likely
1 sibling, 0 replies; 15+ messages in thread
From: Grant Likely @ 2013-02-13 20:47 UTC (permalink / raw)
To: Vineet Gupta
Cc: linux-serial, linux-kernel, Arnd Bergmann, Greg Kroah-Hartman,
devicetree-discuss, Rob Herring, Rob Landley
On Sat, 9 Feb 2013 12:15:10 +0530, Vineet Gupta <Vineet.Gupta1@synopsys.com> wrote:
> On Saturday 09 February 2013 04:31 AM, Grant Likely wrote:
> > On Fri, 11 Jan 2013 11:50:23 +0530, Vineet Gupta <Vineet.Gupta1@synopsys.com> wrote:
> >> +- clock-frequency : the input clock frequency for the UART
> >> +- baud : baud rate for UART
> > change 'baud' to 'current-speed'. There is already precedence for this
> > with other serial devices.
>
> While I'm OK with this - I can only see of_serial.c following the rule :-)
> More importantly I'm not clear about the logistics of this fix. Obviously this has
> a bearing on DT files in arch/arc/boot/*. So are such changes (platform + driver)
> routed thru the subsystem tree or the arch tree or bits from both with
> bisectability not considered - which feels wrong. We have to also consider the
> fact that Greg has closed the tty/serial for 3.9. So while I have no objection to
> your comment, it seems that the it needs to wait till 3.9-rc1 - or is there an
> alternate way.
I would consider it a bug fix. The binding isn't what it should be and
it needs to be addressed before appearing in a released kernel. If this
patch has already been merged, then write and post a fixup patch.
> >
> >> @@ -673,8 +693,18 @@ static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev)
> >> static int arc_serial_probe(struct platform_device *pdev)
> >> {
> >> int rc, dev_id;
> >> + struct device_node *np = pdev->dev.of_node;
> >> +
> >> + /* no device tree device */
> >> + if (!np)
> >> + return -ENODEV;
> > This breaks non-DT users. Is this what you intend? It creates a flag day
> > where users have to switch from non-DT to DT cold-turkey.
>
> Not supporting non-DT user was not the idea - it just simplifies the code a bit
> given that it would only even be runtime used in a ARC Linux port based platform -
> which unconditionally enables OF. Further - the ARC port itself is not yet
> upstream so there are no "official" user of this in tree driver.
> FWIW, ARC Linux port was recently reviewed on lkml/arch mailing lists and is now
> in linux-next for a possible 3.9 merge.
If there are no users, then nobody is broken. If this driver only
supports DT platforms then my comment can be ignored.
> >> + dev_id = of_alias_get_id(np, "serial");
> >> + if (dev_id < 0) {
> >> + dev_err(&pdev->dev, "failed to get alias id: %d\n", dev_id);
> >> + return dev_id;
> >> + }
> > Don't fail on this. If you can't get an id then choose one dynamically.
>
> You mean just assume 0.
No, I mean dynamically assign an ID from ids that are available. Say you
had two of these devices in a system, and neither had an alias; they
couldn't both be '0'. :-)
g.
>
> Thanks for reviewing.
> -Vineet
--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.
^ permalink raw reply [flat|nested] 15+ messages in thread
end of thread, other threads:[~2013-02-13 20:47 UTC | newest]
Thread overview: 15+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2013-01-11 6:20 [PATCH 0/4] switch arc-uart to devicetree based probing Vineet Gupta
2013-01-11 6:20 ` [PATCH 1/4] serial/arc-uart: Don't index with -ve platform_device->id Vineet Gupta
2013-01-11 6:20 ` [PATCH 2/4] serial/arc-uart: split probe from probe_earlyprintk Vineet Gupta
2013-01-11 6:20 ` [PATCH 3/4] serial/arc-uart: platform_data order changed Vineet Gupta
2013-01-11 6:20 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Vineet Gupta
2013-01-11 11:33 ` Arnd Bergmann
2013-01-11 11:55 ` Vineet Gupta
2013-01-11 20:17 ` Arnd Bergmann
2013-02-08 23:01 ` Grant Likely
2013-02-09 6:45 ` Vineet Gupta
2013-02-09 9:28 ` Arnd Bergmann
[not found] ` <1360572101-12744-1-git-send-email-vgupta@synopsys.com>
2013-02-11 8:41 ` [PATCH] serial/arc-uart: Miscll DT related updates (Grant's review comments) Vineet Gupta
2013-02-13 20:47 ` [PATCH 4/4] serial/arc-uart: switch to devicetree based probing Grant Likely
2013-01-16 6:16 ` [PATCH 0/4] switch arc-uart " Greg KH
2013-01-16 6:16 ` Vineet Gupta
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