[PATCH] wl1251: add support for dedicated IRQ line

[PATCH] wl1251: add support for dedicated IRQ line

[Grazvydas Ignotas]

wl1251 has WLAN_IRQ pin for generating interrupts to host processor,
which is mandatory in SPI mode and optional in SDIO mode (which can
use SDIO interrupts instead). However TI recommends using deditated
IRQ line for SDIO too.

Add support for using dedicated interrupt line with SDIO, but also leave
ability to switch to SDIO interrupts in case it's needed.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
---
 drivers/net/wireless/wl12xx/wl1251_sdio.c |   56 ++++++++++++++++++++++++++---
 include/linux/spi/wl12xx.h                |    2 +
 2 files changed, 53 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/wl12xx/wl1251_sdio.c b/drivers/net/wireless/wl12xx/wl1251_sdio.c
index 7409c34..d234285 100644
--- a/drivers/net/wireless/wl12xx/wl1251_sdio.c
+++ b/drivers/net/wireless/wl12xx/wl1251_sdio.c
@@ -25,6 +25,7 @@
 #include <linux/mmc/sdio_ids.h>
 #include <linux/platform_device.h>
 #include <linux/spi/wl12xx.h>
+#include <linux/irq.h>
 
 #include "wl1251.h"
 
@@ -134,18 +135,36 @@ static void wl1251_sdio_disable_irq(struct wl1251 *wl)
 	sdio_release_host(func);
 }
 
+/* Interrupts when using dedicated WLAN_IRQ pin */
+static irqreturn_t wl1251_line_irq(int irq, void *cookie)
+{
+	struct wl1251 *wl = cookie;
+
+	ieee80211_queue_work(wl->hw, &wl->irq_work);
+
+	return IRQ_HANDLED;
+}
+
+static void wl1251_enable_line_irq(struct wl1251 *wl)
+{
+	return enable_irq(wl->irq);
+}
+
+static void wl1251_disable_line_irq(struct wl1251 *wl)
+{
+	return disable_irq(wl->irq);
+}
+
 static void wl1251_sdio_set_power(bool enable)
 {
 }
 
-static const struct wl1251_if_operations wl1251_sdio_ops = {
+static struct wl1251_if_operations wl1251_sdio_ops = {
 	.read = wl1251_sdio_read,
 	.write = wl1251_sdio_write,
 	.write_elp = wl1251_sdio_write_elp,
 	.read_elp = wl1251_sdio_read_elp,
 	.reset = wl1251_sdio_reset,
-	.enable_irq = wl1251_sdio_enable_irq,
-	.disable_irq = wl1251_sdio_disable_irq,
 };
 
 static int wl1251_platform_probe(struct platform_device *pdev)
@@ -191,6 +210,7 @@ static int wl1251_sdio_probe(struct sdio_func *func,
 		goto release;
 
 	sdio_set_block_size(func, 512);
+	sdio_release_host(func);
 
 	SET_IEEE80211_DEV(hw, &func->dev);
 	wl->if_priv = func;
@@ -199,17 +219,41 @@ static int wl1251_sdio_probe(struct sdio_func *func,
 
 	if (wl12xx_board_data != NULL) {
 		wl->set_power = wl12xx_board_data->set_power;
+		wl->irq = wl12xx_board_data->irq;
 		wl->use_eeprom = wl12xx_board_data->use_eeprom;
 	}
 
-	sdio_release_host(func);
+	if (wl->irq) {
+		ret = request_irq(wl->irq, wl1251_line_irq, 0, "wl1251", wl);
+		if (ret < 0) {
+			wl1251_error("request_irq() failed: %d", ret);
+			goto disable;
+		}
+
+		set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
+		disable_irq(wl->irq);
+
+		wl1251_sdio_ops.enable_irq = wl1251_enable_line_irq;
+		wl1251_sdio_ops.disable_irq = wl1251_disable_line_irq;
+
+		wl1251_info("using dedicated interrupt line");
+	} else {
+		wl1251_sdio_ops.enable_irq = wl1251_sdio_enable_irq;
+		wl1251_sdio_ops.disable_irq = wl1251_sdio_disable_irq;
+
+		wl1251_info("using SDIO interrupt");
+	}
+
 	ret = wl1251_init_ieee80211(wl);
 	if (ret)
-		goto disable;
+		goto out_free_irq;
 
 	sdio_set_drvdata(func, wl);
 	return ret;
 
+out_free_irq:
+	if (wl->irq)
+		free_irq(wl->irq, wl);
 disable:
 	sdio_claim_host(func);
 	sdio_disable_func(func);
@@ -222,6 +266,8 @@ static void __devexit wl1251_sdio_remove(struct sdio_func *func)
 {
 	struct wl1251 *wl = sdio_get_drvdata(func);
 
+	if (wl->irq)
+		free_irq(wl->irq, wl);
 	wl1251_free_hw(wl);
 
 	sdio_claim_host(func);
diff --git a/include/linux/spi/wl12xx.h b/include/linux/spi/wl12xx.h
index aed64ed..a223ecb 100644
--- a/include/linux/spi/wl12xx.h
+++ b/include/linux/spi/wl12xx.h
@@ -26,6 +26,8 @@
 
 struct wl12xx_platform_data {
 	void (*set_power)(bool enable);
+	/* SDIO only: IRQ number if WLAN_IRQ line is used, 0 for SDIO IRQs */
+	int irq;
 	bool use_eeprom;
 };
 
-- 
1.6.3.3

Re: [PATCH] wl1251: add support for dedicated IRQ line

[Bob Copeland]

On Fri, Apr 16, 2010 at 01:22:12PM +0300, Grazvydas Ignotas wrote:
> wl1251 has WLAN_IRQ pin for generating interrupts to host processor,
> which is mandatory in SPI mode and optional in SDIO mode (which can
> use SDIO interrupts instead). However TI recommends using deditated
> IRQ line for SDIO too.
> 
> Add support for using dedicated interrupt line with SDIO, but also leave
> ability to switch to SDIO interrupts in case it's needed.
> 
> Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>

Thanks, looks good to me!

Reviewed-by: Bob Copeland <me@bobcopeland.com>

-- 
Bob Copeland %% www.bobcopeland.com

Re: [PATCH] wl1251: add support for dedicated IRQ line

[Kalle Valo]

Grazvydas Ignotas <notasas@gmail.com> writes:

> wl1251 has WLAN_IRQ pin for generating interrupts to host processor,
> which is mandatory in SPI mode and optional in SDIO mode (which can
> use SDIO interrupts instead). However TI recommends using deditated
> IRQ line for SDIO too.
>
> Add support for using dedicated interrupt line with SDIO, but also leave
> ability to switch to SDIO interrupts in case it's needed.

For spi the irq number delivered through struct spi_device, I assume
sdio didn't have any similar mechanism and that's why you added it to
struct wl12xx_platform_data.

Only minor comment is that it would be better to mention also in the
code that the gpio interrupt is the recommended method. But I can add
that comment later.

> Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>

Acked-by: Kalle Valo <kvalo@adurom.com>

Thank you again.

-- 
Kalle Valo

Re: [PATCH] wl1251: add support for dedicated IRQ line

[Grazvydas Ignotas]

On Sat, Apr 17, 2010 at 8:34 AM, Kalle Valo <kvalo@adurom.com> wrote:
> Grazvydas Ignotas <notasas@gmail.com> writes:
>
>> wl1251 has WLAN_IRQ pin for generating interrupts to host processor,
>> which is mandatory in SPI mode and optional in SDIO mode (which can
>> use SDIO interrupts instead). However TI recommends using deditated
>> IRQ line for SDIO too.
>>
>> Add support for using dedicated interrupt line with SDIO, but also leave
>> ability to switch to SDIO interrupts in case it's needed.
>
> For spi the irq number delivered through struct spi_device, I assume
> sdio didn't have any similar mechanism and that's why you added it to
> struct wl12xx_platform_data.

Yes, SDIO currently only reads the card itself for information and
doesn't use any board data at all. This is enough for typical SDIO
card but not in this case, where we have additional signals for power
control and IRQ.

> Only minor comment is that it would be better to mention also in the
> code that the gpio interrupt is the recommended method. But I can add
> that comment later.

Will have that in mind too if I send something more, thanks.

>> Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
>
> Acked-by: Kalle Valo <kvalo@adurom.com>
>
> Thank you again.
>
> --
> Kalle Valo
>