ASoC: ti: davinci-mcasp: Add support for GPIO mode of the pins

All McASP pin can be configured as GPIO.
Add gpiochip support for McASP and only enable it when the
gpio-controller is present in the DT node.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
index a6a470a7690034b8380ac5f2077bd7cc227a7dd1..a3a67a8f0f543ab047addec631d3f3743a7fb0fd 100644 (file)
--- a/sound/soc/ti/davinci-mcasp.c
+++ b/sound/soc/ti/davinci-mcasp.c
@@ -29,6 +29,7 @@
 #include <linux/platform_data/davinci_asp.h>
 #include <linux/math64.h>
 #include <linux/bitmap.h>
+#include <linux/gpio/driver.h>
 
 #include <sound/asoundef.h>
 #include <sound/core.h>
@@ -54,6 +55,7 @@ static u32 context_regs[] = {
        DAVINCI_MCASP_AHCLKXCTL_REG,
        DAVINCI_MCASP_AHCLKRCTL_REG,
        DAVINCI_MCASP_PDIR_REG,
+       DAVINCI_MCASP_PFUNC_REG,
        DAVINCI_MCASP_RXMASK_REG,
        DAVINCI_MCASP_TXMASK_REG,
        DAVINCI_MCASP_RXTDM_REG,
@@ -108,6 +110,10 @@ struct davinci_mcasp {
        /* Used for comstraint setting on the second stream */
        u32     channels;
 
+#ifdef CONFIG_GPIOLIB
+       struct gpio_chip gpio_chip;
+#endif
+
 #ifdef CONFIG_PM
        struct davinci_mcasp_context context;
 #endif
@@ -818,9 +824,6 @@ static int mcasp_common_hw_param(struct davinci_mcasp *mcasp, int stream,
        if (mcasp->version < MCASP_VERSION_3)
                mcasp_set_bits(mcasp, DAVINCI_MCASP_PWREMUMGT_REG, MCASP_SOFT);
 
-       /* All PINS as McASP */
-       mcasp_set_reg(mcasp, DAVINCI_MCASP_PFUNC_REG, 0x00000000);
-
        if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
                mcasp_set_reg(mcasp, DAVINCI_MCASP_TXSTAT_REG, 0xFFFFFFFF);
                mcasp_clr_bits(mcasp, DAVINCI_MCASP_XEVTCTL_REG, TXDATADMADIS);
@@ -1845,6 +1848,147 @@ static u32 davinci_mcasp_rxdma_offset(struct davinci_mcasp_pdata *pdata)
        return offset;
 }
 
+#ifdef CONFIG_GPIOLIB
+static int davinci_mcasp_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+       struct davinci_mcasp *mcasp = gpiochip_get_data(chip);
+
+       if (mcasp->num_serializer && offset < mcasp->num_serializer &&
+           mcasp->serial_dir[offset] != INACTIVE_MODE) {
+               dev_err(mcasp->dev, "AXR%u pin is  used for audio\n", offset);
+               return -EBUSY;
+       }
+
+       /* Do not change the PIN yet */
+
+       return pm_runtime_get_sync(mcasp->dev);
+}
+
+static void davinci_mcasp_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+       struct davinci_mcasp *mcasp = gpiochip_get_data(chip);
+
+       /* Set the direction to input */
+       mcasp_clr_bits(mcasp, DAVINCI_MCASP_PDIR_REG, BIT(offset));
+
+       /* Set the pin as McASP pin */
+       mcasp_clr_bits(mcasp, DAVINCI_MCASP_PFUNC_REG, BIT(offset));
+
+       pm_runtime_put_sync(mcasp->dev);
+}
+
+static int davinci_mcasp_gpio_direction_out(struct gpio_chip *chip,
+                                           unsigned offset, int value)
+{
+       struct davinci_mcasp *mcasp = gpiochip_get_data(chip);
+       u32 val;
+
+       if (value)
+               mcasp_set_bits(mcasp, DAVINCI_MCASP_PDOUT_REG, BIT(offset));
+       else
+               mcasp_clr_bits(mcasp, DAVINCI_MCASP_PDOUT_REG, BIT(offset));
+
+       val = mcasp_get_reg(mcasp, DAVINCI_MCASP_PFUNC_REG);
+       if (!(val & BIT(offset))) {
+               /* Set the pin as GPIO pin */
+               mcasp_set_bits(mcasp, DAVINCI_MCASP_PFUNC_REG, BIT(offset));
+
+               /* Set the direction to output */
+               mcasp_set_bits(mcasp, DAVINCI_MCASP_PDIR_REG, BIT(offset));
+       }
+
+       return 0;
+}
+
+static void davinci_mcasp_gpio_set(struct gpio_chip *chip, unsigned offset,
+                                 int value)
+{
+       struct davinci_mcasp *mcasp = gpiochip_get_data(chip);
+
+       if (value)
+               mcasp_set_bits(mcasp, DAVINCI_MCASP_PDOUT_REG, BIT(offset));
+       else
+               mcasp_clr_bits(mcasp, DAVINCI_MCASP_PDOUT_REG, BIT(offset));
+}
+
+static int davinci_mcasp_gpio_direction_in(struct gpio_chip *chip,
+                                          unsigned offset)
+{
+       struct davinci_mcasp *mcasp = gpiochip_get_data(chip);
+       u32 val;
+
+       val = mcasp_get_reg(mcasp, DAVINCI_MCASP_PFUNC_REG);
+       if (!(val & BIT(offset))) {
+               /* Set the direction to input */
+               mcasp_clr_bits(mcasp, DAVINCI_MCASP_PDIR_REG, BIT(offset));
+
+               /* Set the pin as GPIO pin */
+               mcasp_set_bits(mcasp, DAVINCI_MCASP_PFUNC_REG, BIT(offset));
+       }
+
+       return 0;
+}
+
+static int davinci_mcasp_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+       struct davinci_mcasp *mcasp = gpiochip_get_data(chip);
+       u32 val;
+
+       val = mcasp_get_reg(mcasp, DAVINCI_MCASP_PDSET_REG);
+       if (val & BIT(offset))
+               return 1;
+
+       return 0;
+}
+
+static int davinci_mcasp_gpio_get_direction(struct gpio_chip *chip,
+                                           unsigned offset)
+{
+       struct davinci_mcasp *mcasp = gpiochip_get_data(chip);
+       u32 val;
+
+       val = mcasp_get_reg(mcasp, DAVINCI_MCASP_PDIR_REG);
+       if (val & BIT(offset))
+               return 0;
+
+       return 1;
+}
+
+static const struct gpio_chip davinci_mcasp_template_chip = {
+       .owner                  = THIS_MODULE,
+       .request                = davinci_mcasp_gpio_request,
+       .free                   = davinci_mcasp_gpio_free,
+       .direction_output       = davinci_mcasp_gpio_direction_out,
+       .set                    = davinci_mcasp_gpio_set,
+       .direction_input        = davinci_mcasp_gpio_direction_in,
+       .get                    = davinci_mcasp_gpio_get,
+       .get_direction          = davinci_mcasp_gpio_get_direction,
+       .base                   = -1,
+       .ngpio                  = 32,
+};
+
+static int davinci_mcasp_init_gpiochip(struct davinci_mcasp *mcasp)
+{
+       if (!of_property_read_bool(mcasp->dev->of_node, "gpio-controller"))
+               return 0;
+
+       mcasp->gpio_chip = davinci_mcasp_template_chip;
+       mcasp->gpio_chip.label = dev_name(mcasp->dev);
+       mcasp->gpio_chip.parent = mcasp->dev;
+#ifdef CONFIG_OF_GPIO
+       mcasp->gpio_chip.of_node = mcasp->dev->of_node;
+#endif
+
+       return devm_gpiochip_add_data(mcasp->dev, &mcasp->gpio_chip, mcasp);
+}
+
+#else /* CONFIG_GPIOLIB */
+static inline int davinci_mcasp_init_gpiochip(struct davinci_mcasp *mcasp)
+{
+       return 0;
+}
+#endif /* CONFIG_GPIOLIB */
+
 static int davinci_mcasp_probe(struct platform_device *pdev)
 {
        struct snd_dmaengine_dai_dma_data *dma_data;
@@ -2069,6 +2213,15 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
 
        mcasp_reparent_fck(pdev);
 
+       /* All PINS as McASP */
+       pm_runtime_get_sync(mcasp->dev);
+       mcasp_set_reg(mcasp, DAVINCI_MCASP_PFUNC_REG, 0x00000000);
+       pm_runtime_put(mcasp->dev);
+
+       ret = davinci_mcasp_init_gpiochip(mcasp);
+       if (ret)
+               goto err;
+
        ret = devm_snd_soc_register_component(&pdev->dev,
                                        &davinci_mcasp_component,
                                        &davinci_mcasp_dai[pdata->op_mode], 1);