[v2,3/3] serial: amba-pl011: add ACPI support to AMBA probe

Message ID 1450709399-7246-4-git-send-email-aleksey.makarov@linaro.org
State New
Headers show

Commit Message

Aleksey Makarov Dec. 21, 2015, 2:49 p.m.
From: Graeme Gregory <graeme.gregory@linaro.org>


In ACPI this device is only defined in SBSA mode so
if we are coming from ACPI use this mode.

Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>

Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>

---
 drivers/tty/serial/amba-pl011.c | 37 ++++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 11 deletions(-)

-- 
2.6.4

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Comments

Graeme Gregory Dec. 21, 2015, 9:02 p.m. | #1
On 21 December 2015 at 18:11, Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
> On Mon, Dec 21, 2015 at 4:49 PM, Aleksey Makarov

> <aleksey.makarov@linaro.org> wrote:

>> From: Graeme Gregory <graeme.gregory@linaro.org>

>>

>> In ACPI this device is only defined in SBSA mode so

>> if we are coming from ACPI use this mode.

>>

>> Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>

>> Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>

>> ---

>>  drivers/tty/serial/amba-pl011.c | 37 ++++++++++++++++++++++++++-----------

>>  1 file changed, 26 insertions(+), 11 deletions(-)

>>

>> diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c

>> index 899a771..766ce4f 100644

>> --- a/drivers/tty/serial/amba-pl011.c

>> +++ b/drivers/tty/serial/amba-pl011.c

>> @@ -2368,18 +2368,33 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)

>>         if (!uap)

>>                 return -ENOMEM;

>>

>> -       uap->clk = devm_clk_get(&dev->dev, NULL);

>> -       if (IS_ERR(uap->clk))

>> -               return PTR_ERR(uap->clk);

>> -

>> -       uap->vendor = vendor;

>> -       uap->lcrh_rx = vendor->lcrh_rx;

>> -       uap->lcrh_tx = vendor->lcrh_tx;

>> -       uap->fifosize = vendor->get_fifosize(dev);

>> -       uap->port.irq = dev->irq[0];

>> -       uap->port.ops = &amba_pl011_pops;

>> +       /* ACPI only defines SBSA variant */

>> +       if (ACPI_COMPANION(&dev->dev)) {

>

> has_acpi_companion()

>

>> +               /*

>> +                * According to ARM ARMH0011 is currently the only mapping

>> +                * of pl011 in ACPI and it's mapped to SBSA UART mode

>> +                */

>> +               uap->vendor     = &vendor_sbsa;

>> +               uap->fifosize   = 32;

>> +               uap->port.ops   = &sbsa_uart_pops;

>> +               uap->fixed_baud = 115200;

>

> Shouldn't you match by ID and provide the custom values if any?

> On the other hand have you checked if it's possible to use _DSD in this case?

>

So far I have not seen any use of SBSA UART other than this in real
life. I am a little opposed to providing complexity people are not
going to use.

Graeme
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Patch

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 899a771..766ce4f 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2368,18 +2368,33 @@  static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
 	if (!uap)
 		return -ENOMEM;
 
-	uap->clk = devm_clk_get(&dev->dev, NULL);
-	if (IS_ERR(uap->clk))
-		return PTR_ERR(uap->clk);
-
-	uap->vendor = vendor;
-	uap->lcrh_rx = vendor->lcrh_rx;
-	uap->lcrh_tx = vendor->lcrh_tx;
-	uap->fifosize = vendor->get_fifosize(dev);
-	uap->port.irq = dev->irq[0];
-	uap->port.ops = &amba_pl011_pops;
+	/* ACPI only defines SBSA variant */
+	if (ACPI_COMPANION(&dev->dev)) {
+		/*
+		 * According to ARM ARMH0011 is currently the only mapping
+		 * of pl011 in ACPI and it's mapped to SBSA UART mode
+		 */
+		uap->vendor	= &vendor_sbsa;
+		uap->fifosize	= 32;
+		uap->port.ops	= &sbsa_uart_pops;
+		uap->fixed_baud = 115200;
 
-	snprintf(uap->type, sizeof(uap->type), "PL011 rev%u", amba_rev(dev));
+		snprintf(uap->type, sizeof(uap->type), "SBSA");
+	} else {
+		uap->clk = devm_clk_get(&dev->dev, NULL);
+		if (IS_ERR(uap->clk))
+			return PTR_ERR(uap->clk);
+
+		uap->vendor = vendor;
+		uap->lcrh_rx = vendor->lcrh_rx;
+		uap->lcrh_tx = vendor->lcrh_tx;
+		uap->fifosize = vendor->get_fifosize(dev);
+		uap->port.ops = &amba_pl011_pops;
+
+		snprintf(uap->type, sizeof(uap->type), "PL011 rev%u",
+				amba_rev(dev));
+	}
+	uap->port.irq = dev->irq[0];
 
 	ret = pl011_setup_port(&dev->dev, uap, &dev->res, portnr);
 	if (ret)