diff mbox

[v10,1/7] ASoC: core: Generic ac97 link reset functions

Message ID 1374924716-23475-2-git-send-email-mpa@pengutronix.de (mailing list archive)
State New, archived
Headers show

Commit Message

Markus Pargmann July 27, 2013, 11:31 a.m. UTC 
This patch adds generic ac97 reset functions using pincontrol and gpio
parsed from devicetree.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
---
 .../devicetree/bindings/sound/soc-ac97link.txt     |  28 ++++
 include/sound/soc.h                                |   2 +
 sound/soc/soc-core.c                               | 153 +++++++++++++++++++++
 3 files changed, 183 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/soc-ac97link.txt

Comments

Mark Brown July 27, 2013, 12:05 p.m. UTC | #1 
On Sat, Jul 27, 2013 at 01:31:50PM +0200, Markus Pargmann wrote:

This is a really nice approach to the problem, just one thing I'd like
to see changed in the bindings:

> +ssi {
> +	...
> +
> +	pinctrl-names = "default", "ac97-running", "ac97-reset", "ac97-warm-reset";

I'd like to see some documentation of this "default" state - I'd expect
this corresponds to the bus being idle and waiting for a wakeup from the
CODEC which is definitely a useful state to have for power optimisation
so it'd be good to bake it into the bindings.

Alternatively it could be the bus being totally idle with no possibility
of wakeup in which case it'd be good to say that too then someone can
add the waiting for wakeup state later.

Please also note the new list devicetree@vger.kernel.org.
Markus Pargmann July 27, 2013, 1:55 p.m. UTC | #2 
On Sat, Jul 27, 2013 at 01:05:22PM +0100, Mark Brown wrote:
> On Sat, Jul 27, 2013 at 01:31:50PM +0200, Markus Pargmann wrote:
> 
> This is a really nice approach to the problem, just one thing I'd like
> to see changed in the bindings:
> 
> > +ssi {
> > +	...
> > +
> > +	pinctrl-names = "default", "ac97-running", "ac97-reset", "ac97-warm-reset";
> 
> I'd like to see some documentation of this "default" state - I'd expect
> this corresponds to the bus being idle and waiting for a wakeup from the
> CODEC which is definitely a useful state to have for power optimisation
> so it'd be good to bake it into the bindings.
> 
> Alternatively it could be the bus being totally idle with no possibility
> of wakeup in which case it'd be good to say that too then someone can
> add the waiting for wakeup state later.

The "default" state is actually just the default pin state that is set
before the driver is probed. I will remove it from the example. I didn't
add a low power state although it might be usefull and is defined by the
standard.

> 
> Please also note the new list devicetree@vger.kernel.org.

Yes thanks.

Regards,

Markus
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/sound/soc-ac97link.txt b/Documentation/devicetree/bindings/sound/soc-ac97link.txt
new file mode 100644
index 0000000..80152a8
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/soc-ac97link.txt
@@ -0,0 +1,28 @@ 
+AC97 link bindings
+
+These bindings can be included within any other device node.
+
+Required properties:
+ - pinctrl-names: Has to contain following states to setup the correct
+   pinmuxing for the used gpios:
+	"ac97-running": AC97-link is active
+	"ac97-reset": AC97-link reset state
+	"ac97-warm-reset": AC97-link warm reset state
+ - ac97-gpios: List of gpio phandles with args in the order ac97-sync,
+   ac97-sdata, ac97-reset
+
+
+Example:
+
+ssi {
+	...
+
+	pinctrl-names = "default", "ac97-running", "ac97-reset", "ac97-warm-reset";
+	pinctrl-0 = <&ac97link_running>;
+	pinctrl-1 = <&ac97link_running>;
+	pinctrl-2 = <&ac97link_reset>;
+	pinctrl-3 = <&ac97link_warm_reset>;
+	ac97-gpios = <&gpio3 20 0 &gpio3 22 0 &gpio3 28 0>;
+
+	...
+};
diff --git a/include/sound/soc.h b/include/sound/soc.h
index 6eabee7..c0ac3bc 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -468,6 +468,8 @@  int snd_soc_new_ac97_codec(struct snd_soc_codec *codec,
 void snd_soc_free_ac97_codec(struct snd_soc_codec *codec);
 
 int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops);
+int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
+		struct platform_device *pdev);
 
 /*
  *Controls
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 0ec070c..6010932 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -30,9 +30,12 @@ 
 #include <linux/bitops.h>
 #include <linux/debugfs.h>
 #include <linux/platform_device.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/ctype.h>
 #include <linux/slab.h>
 #include <linux/of.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
 #include <sound/ac97_codec.h>
 #include <sound/core.h>
 #include <sound/jack.h>
@@ -69,6 +72,16 @@  static int pmdown_time = 5000;
 module_param(pmdown_time, int, 0);
 MODULE_PARM_DESC(pmdown_time, "DAPM stream powerdown time (msecs)");
 
+struct snd_ac97_reset_cfg {
+	struct pinctrl *pctl;
+	struct pinctrl_state *pstate_reset;
+	struct pinctrl_state *pstate_warm_reset;
+	struct pinctrl_state *pstate_run;
+	int gpio_sdata;
+	int gpio_sync;
+	int gpio_reset;
+};
+
 /* returns the minimum number of bytes needed to represent
  * a particular given value */
 static int min_bytes_needed(unsigned long val)
@@ -2080,6 +2093,117 @@  int snd_soc_new_ac97_codec(struct snd_soc_codec *codec,
 }
 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_codec);
 
+static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
+
+static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
+{
+	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
+
+	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
+
+	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
+
+	udelay(10);
+
+	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
+
+	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
+	msleep(2);
+}
+
+static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
+{
+	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
+
+	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
+
+	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
+	gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
+	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
+
+	udelay(10);
+
+	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
+
+	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
+	msleep(2);
+}
+
+static int snd_soc_ac97_parse_pinctl(struct device *dev,
+		struct snd_ac97_reset_cfg *cfg)
+{
+	struct pinctrl *p;
+	struct pinctrl_state *state;
+	int gpio;
+	int ret;
+
+	p = devm_pinctrl_get(dev);
+	if (IS_ERR(p)) {
+		dev_err(dev, "Failed to get pinctrl\n");
+		return PTR_RET(p);
+	}
+	cfg->pctl = p;
+
+	state = pinctrl_lookup_state(p, "ac97-reset");
+	if (IS_ERR(state)) {
+		dev_err(dev, "Can't find pinctrl state ac97-reset\n");
+		return PTR_RET(state);
+	}
+	cfg->pstate_reset = state;
+
+	state = pinctrl_lookup_state(p, "ac97-warm-reset");
+	if (IS_ERR(state)) {
+		dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
+		return PTR_RET(state);
+	}
+	cfg->pstate_warm_reset = state;
+
+	state = pinctrl_lookup_state(p, "ac97-running");
+	if (IS_ERR(state)) {
+		dev_err(dev, "Can't find pinctrl state ac97-running\n");
+		return PTR_RET(state);
+	}
+	cfg->pstate_run = state;
+
+	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
+	if (gpio < 0) {
+		dev_err(dev, "Can't find ac97-sync gpio\n");
+		return gpio;
+	}
+	ret = devm_gpio_request(dev, gpio, "AC97 link sync");
+	if (ret) {
+		dev_err(dev, "Failed requesting ac97-sync gpio\n");
+		return ret;
+	}
+	cfg->gpio_sync = gpio;
+
+	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
+	if (gpio < 0) {
+		dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
+		return gpio;
+	}
+	ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
+	if (ret) {
+		dev_err(dev, "Failed requesting ac97-sdata gpio\n");
+		return ret;
+	}
+	cfg->gpio_sdata = gpio;
+
+	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
+	if (gpio < 0) {
+		dev_err(dev, "Can't find ac97-reset gpio\n");
+		return gpio;
+	}
+	ret = devm_gpio_request(dev, gpio, "AC97 link reset");
+	if (ret) {
+		dev_err(dev, "Failed requesting ac97-reset gpio\n");
+		return ret;
+	}
+	cfg->gpio_reset = gpio;
+
+	return 0;
+}
+
 struct snd_ac97_bus_ops *soc_ac97_ops;
 EXPORT_SYMBOL_GPL(soc_ac97_ops);
 
@@ -2098,6 +2222,35 @@  int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
 EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
 
 /**
+ * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
+ *
+ * This function sets the reset and warm_reset properties of ops and parses
+ * the device node of pdev to get pinctrl states and gpio numbers to use.
+ */
+int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
+		struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct snd_ac97_reset_cfg cfg;
+	int ret;
+
+	ret = snd_soc_ac97_parse_pinctl(dev, &cfg);
+	if (ret)
+		return ret;
+
+	ret = snd_soc_set_ac97_ops(ops);
+	if (ret)
+		return ret;
+
+	ops->warm_reset = snd_soc_ac97_warm_reset;
+	ops->reset = snd_soc_ac97_reset;
+
+	snd_ac97_rst_cfg = cfg;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset);
+
+/**
  * snd_soc_free_ac97_codec - free AC97 codec device
  * @codec: audio codec
  *