[PATCH v7 05/12] mux: support simplified bindings for single-user gpio mux

From: Peter Rosin
Date: Wed Jan 04 2017 - 07:18:27 EST


Signed-off-by: Peter Rosin <peda@xxxxxxxxxx>
---
drivers/mux/mux-core.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++++--
drivers/mux/mux-gpio.c | 56 ++--------------------------------
include/linux/mux.h | 7 +++++
3 files changed, 89 insertions(+), 55 deletions(-)

diff --git a/drivers/mux/mux-core.c b/drivers/mux/mux-core.c
index 21da15a264ad..d887ae1c0e55 100644
--- a/drivers/mux/mux-core.c
+++ b/drivers/mux/mux-core.c
@@ -15,6 +15,7 @@
#include <linux/device.h>
#include <linux/err.h>
#include <linux/idr.h>
+#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/mux.h>
#include <linux/of.h>
@@ -288,6 +289,63 @@ static struct mux_chip *of_find_mux_chip_by_node(struct device_node *np)
return dev ? to_mux_chip(dev) : NULL;
}

+#ifdef CONFIG_MUX_GPIO
+
+static int mux_gpio_set(struct mux_control *mux, int state)
+{
+ struct mux_gpio *mux_gpio = mux_chip_priv(mux->chip);
+ int i;
+
+ for (i = 0; i < mux_gpio->gpios->ndescs; i++)
+ mux_gpio->val[i] = (state >> i) & 1;
+
+ gpiod_set_array_value_cansleep(mux_gpio->gpios->ndescs,
+ mux_gpio->gpios->desc,
+ mux_gpio->val);
+
+ return 0;
+}
+
+static const struct mux_control_ops mux_gpio_ops = {
+ .set = mux_gpio_set,
+};
+
+struct mux_chip *mux_gpio_alloc(struct device *dev)
+{
+ struct mux_chip *mux_chip;
+ struct mux_gpio *mux_gpio;
+ int pins;
+ int ret;
+
+ pins = gpiod_count(dev, "mux");
+ if (pins < 0)
+ return ERR_PTR(pins);
+
+ mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*mux_gpio) +
+ pins * sizeof(*mux_gpio->val));
+ if (!mux_chip)
+ return ERR_PTR(-ENOMEM);
+
+ mux_gpio = mux_chip_priv(mux_chip);
+ mux_gpio->val = (int *)(mux_gpio + 1);
+ mux_chip->ops = &mux_gpio_ops;
+
+ mux_gpio->gpios = devm_gpiod_get_array(dev, "mux", GPIOD_OUT_LOW);
+ if (IS_ERR(mux_gpio->gpios)) {
+ ret = PTR_ERR(mux_gpio->gpios);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to get gpios\n");
+ return ERR_PTR(ret);
+ }
+ WARN_ON(pins != mux_gpio->gpios->ndescs);
+ mux_chip->mux->states = 1 << pins;
+
+ return mux_chip;
+}
+EXPORT_SYMBOL_GPL(mux_gpio_alloc);
+
+#endif /* CONFIG_MUX_GPIO */
+
struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
{
struct device_node *np = dev->of_node;
@@ -307,9 +365,28 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
ret = of_parse_phandle_with_args(np,
"mux-controls", "#mux-control-cells",
index, &args);
+
+#ifdef CONFIG_MUX_GPIO
+ if (ret == -ENOENT && !mux_name && gpiod_count(dev, "mux") > 0) {
+ mux_chip = mux_gpio_alloc(dev);
+ if (!IS_ERR(mux_chip)) {
+ ret = devm_mux_chip_register(dev, mux_chip);
+ if (ret < 0) {
+ dev_err(dev, "failed to register mux-chip\n");
+ return ERR_PTR(ret);
+ }
+ get_device(&mux_chip->dev);
+ return mux_chip->mux;
+ }
+
+ ret = PTR_ERR(mux_chip);
+ }
+#endif
+
if (ret) {
- dev_err(dev, "%s: failed to get mux-control %s(%i)\n",
- np->full_name, mux_name ?: "", index);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "%s: failed to get mux-control %s(%i)\n",
+ np->full_name, mux_name ?: "", index);
return ERR_PTR(ret);
}

diff --git a/drivers/mux/mux-gpio.c b/drivers/mux/mux-gpio.c
index 76b52bc63470..8a7bfbc0c4bb 100644
--- a/drivers/mux/mux-gpio.c
+++ b/drivers/mux/mux-gpio.c
@@ -11,37 +11,12 @@
*/

#include <linux/err.h>
-#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/mux.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/property.h>

-struct mux_gpio {
- struct gpio_descs *gpios;
- int *val;
-};
-
-static int mux_gpio_set(struct mux_control *mux, int state)
-{
- struct mux_gpio *mux_gpio = mux_chip_priv(mux->chip);
- int i;
-
- for (i = 0; i < mux_gpio->gpios->ndescs; i++)
- mux_gpio->val[i] = (state >> i) & 1;
-
- gpiod_set_array_value_cansleep(mux_gpio->gpios->ndescs,
- mux_gpio->gpios->desc,
- mux_gpio->val);
-
- return 0;
-}
-
-static const struct mux_control_ops mux_gpio_ops = {
- .set = mux_gpio_set,
-};
-
static const struct of_device_id mux_gpio_dt_ids[] = {
{ .compatible = "mux-gpio", },
{ /* sentinel */ }
@@ -51,38 +26,13 @@ MODULE_DEVICE_TABLE(of, mux_gpio_dt_ids);
static int mux_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
- struct device_node *np = dev->of_node;
struct mux_chip *mux_chip;
- struct mux_gpio *mux_gpio;
- int pins;
u32 idle_state;
int ret;

- if (!np)
- return -ENODEV;
-
- pins = gpiod_count(dev, "mux");
- if (pins < 0)
- return pins;
-
- mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*mux_gpio) +
- pins * sizeof(*mux_gpio->val));
- if (!mux_chip)
- return -ENOMEM;
-
- mux_gpio = mux_chip_priv(mux_chip);
- mux_gpio->val = (int *)(mux_gpio + 1);
- mux_chip->ops = &mux_gpio_ops;
-
- mux_gpio->gpios = devm_gpiod_get_array(dev, "mux", GPIOD_OUT_LOW);
- if (IS_ERR(mux_gpio->gpios)) {
- ret = PTR_ERR(mux_gpio->gpios);
- if (ret != -EPROBE_DEFER)
- dev_err(dev, "failed to get gpios\n");
- return ret;
- }
- WARN_ON(pins != mux_gpio->gpios->ndescs);
- mux_chip->mux->states = 1 << pins;
+ mux_chip = mux_gpio_alloc(dev);
+ if (IS_ERR(mux_chip))
+ return PTR_ERR(mux_chip);

ret = device_property_read_u32(dev, "idle-state", &idle_state);
if (ret >= 0) {
diff --git a/include/linux/mux.h b/include/linux/mux.h
index 3b9439927f11..3bfee23cfb8c 100644
--- a/include/linux/mux.h
+++ b/include/linux/mux.h
@@ -241,4 +241,11 @@ struct mux_control *devm_mux_control_get(struct device *dev,
*/
void devm_mux_control_put(struct device *dev, struct mux_control *mux);

+struct mux_gpio {
+ struct gpio_descs *gpios;
+ int *val;
+};
+
+struct mux_chip *mux_gpio_alloc(struct device *dev);
+
#endif /* _LINUX_MUX_H */
--
2.1.4