@@ -10,6 +10,7 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/clk.h>
+#include <linux/gpio/driver.h>
#include <linux/kernel.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
@@ -32,6 +33,7 @@ static const char * const pcm512x_supply_names[PCM512x_NUM_SUPPLIES] = {
struct pcm512x_priv {
struct regmap *regmap;
struct clk *sclk;
+ struct gpio_chip chip;
struct regulator_bulk_data supplies[PCM512x_NUM_SUPPLIES];
struct notifier_block supply_nb[PCM512x_NUM_SUPPLIES];
int fmt;
@@ -1503,6 +1505,102 @@ const struct regmap_config pcm512x_regmap = {
};
EXPORT_SYMBOL_GPL(pcm512x_regmap);
+static int pcm512x_gpio_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ struct pcm512x_priv *pcm512x = gpiochip_get_data(chip);
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(pcm512x->regmap, PCM512x_GPIO_EN, &val);
+ if (ret < 0)
+ return ret;
+
+ val = (val >> offset) & 1;
+
+ /* val is 0 for input, 1 for output, return inverted */
+ return val ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
+}
+
+static int pcm512x_gpio_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ struct pcm512x_priv *pcm512x = gpiochip_get_data(chip);
+
+ return regmap_update_bits(pcm512x->regmap, PCM512x_GPIO_EN,
+ BIT(offset), 0);
+}
+
+static int pcm512x_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset,
+ int value)
+{
+ struct pcm512x_priv *pcm512x = gpiochip_get_data(chip);
+ unsigned int reg;
+ int ret;
+
+ /* select Register GPIOx output for OUTPUT_x (1..6) */
+ reg = PCM512x_GPIO_OUTPUT_1 + offset;
+ ret = regmap_update_bits(pcm512x->regmap, reg, 0x0f, 0x02);
+ if (ret < 0)
+ return ret;
+
+ /* enable output x */
+ ret = regmap_update_bits(pcm512x->regmap, PCM512x_GPIO_EN,
+ BIT(offset), BIT(offset));
+ if (ret < 0)
+ return ret;
+
+ /* set value */
+ return regmap_update_bits(pcm512x->regmap, PCM512x_GPIO_CONTROL_1,
+ BIT(offset), value << offset);
+}
+
+static int pcm512x_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct pcm512x_priv *pcm512x = gpiochip_get_data(chip);
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(pcm512x->regmap, PCM512x_GPIO_CONTROL_1, &val);
+ if (ret < 0)
+ return ret;
+
+ return (val >> offset) & 1;
+}
+
+static void pcm512x_gpio_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct pcm512x_priv *pcm512x = gpiochip_get_data(chip);
+ int ret;
+
+ ret = regmap_update_bits(pcm512x->regmap, PCM512x_GPIO_CONTROL_1,
+ BIT(offset), value << offset);
+
+ if (ret < 0)
+ pr_debug("%s: regmap_update_bits failed: %d\n", __func__, ret);
+}
+
+/* list human-readable names, makes GPIOLIB usage straightforward */
+static const char * const pcm512x_gpio_names[] = {
+ "PCM512x-GPIO1", "PCM512x-GPIO2", "PCM512x-GPIO3",
+ "PCM512x-GPIO4", "PCM512x-GPIO5", "PCM512x-GPIO6"
+};
+
+static const struct gpio_chip template_chip = {
+ .label = "pcm512x-gpio",
+ .names = pcm512x_gpio_names,
+ .owner = THIS_MODULE,
+ .get_direction = pcm512x_gpio_get_direction,
+ .direction_input = pcm512x_gpio_direction_input,
+ .direction_output = pcm512x_gpio_direction_output,
+ .get = pcm512x_gpio_get,
+ .set = pcm512x_gpio_set,
+ .base = -1, /* let gpiolib select the base */
+ .ngpio = ARRAY_SIZE(pcm512x_gpio_names),
+};
+
int pcm512x_probe(struct device *dev, struct regmap *regmap)
{
struct pcm512x_priv *pcm512x;
@@ -1563,6 +1661,16 @@ int pcm512x_probe(struct device *dev, struct regmap *regmap)
goto err;
}
+ /* expose 6 GPIO pins, numbered from 1 to 6 */
+ pcm512x->chip = template_chip;
+ pcm512x->chip.parent = dev;
+
+ ret = devm_gpiochip_add_data(dev, &pcm512x->chip, pcm512x);
+ if (ret != 0) {
+ dev_err(dev, "Failed to register gpio chip: %d\n", ret);
+ goto err;
+ }
+
pcm512x->sclk = devm_clk_get(dev, NULL);
if (PTR_ERR(pcm512x->sclk) == -EPROBE_DEFER) {
ret = -EPROBE_DEFER;
The GPIOs are used e.g. on HifiBerry DAC+ HATs to control the LED (GPIO3) and the choice of the 44.1 (GPIO6) or 48 (GPIO3) kHz oscillator (when present). Enable basic gpio_chip to get/set values and get/set directions. Tested with GPIO_LIB from sys/class/gpio, the LED turns on/off as desired. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> --- sound/soc/codecs/pcm512x.c | 108 +++++++++++++++++++++++++++++++++++++ 1 file changed, 108 insertions(+)