ALSA: ctxfi: Add ADC helper functions for GPIO

Add helper functions hw_adc_stop(), hw_adc_start(), and hw_adc_reset()
to encapsulate ADC reset sequence operations. These functions reduce
duplication by centralizing the GPIO-based ADC control logic.

Signed-off-by: Harin Lee <me@harin.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20251124180501.2760421-3-me@harin.net

diff --git a/sound/pci/ctxfi/cthw20k2.c b/sound/pci/ctxfi/cthw20k2.c
index 1a085e7e57869b68fb64c85c90882704830afaf9..5d39bc943648c160295a17edb945fad7f1792e59 100644 (file)
--- a/sound/pci/ctxfi/cthw20k2.c
+++ b/sound/pci/ctxfi/cthw20k2.c
@@ -1826,6 +1826,32 @@ static int hw_adc_input_select(struct hw *hw, enum ADCSRC type)
        return 0;
 }
 
+static void hw_adc_stop(struct hw *hw)
+{
+       u32 data;
+       /* Reset the ADC (reset is active low). */
+       data = hw_read_20kx(hw, GPIO_DATA);
+       data &= ~(0x1 << 15);
+       hw_write_20kx(hw, GPIO_DATA, data);
+       usleep_range(10000, 11000);
+}
+
+static void hw_adc_start(struct hw *hw)
+{
+       u32 data;
+       /* Return the ADC to normal operation. */
+       data = hw_read_20kx(hw, GPIO_DATA);
+       data |= (0x1 << 15);
+       hw_write_20kx(hw, GPIO_DATA, data);
+       msleep(50);
+}
+
+static void __maybe_unused hw_adc_reset(struct hw *hw)
+{
+       hw_adc_stop(hw);
+       hw_adc_start(hw);
+}
+
 static int hw_adc_init(struct hw *hw, const struct adc_conf *info)
 {
        int err;
@@ -1843,10 +1869,7 @@ static int hw_adc_init(struct hw *hw, const struct adc_conf *info)
                goto error;
        }
 
-       /* Reset the ADC (reset is active low). */
-       data = hw_read_20kx(hw, GPIO_DATA);
-       data &= ~(0x1 << 15);
-       hw_write_20kx(hw, GPIO_DATA, data);
+       hw_adc_stop(hw);
 
        if (hw->model == CTSB1270) {
                /* Set up the PCM4220 ADC on Titanium HD */
@@ -1860,11 +1883,7 @@ static int hw_adc_init(struct hw *hw, const struct adc_conf *info)
                hw_write_20kx(hw, GPIO_DATA, data);
        }
 
-       usleep_range(10000, 11000);
-       /* Return the ADC to normal operation. */
-       data |= (0x1 << 15);
-       hw_write_20kx(hw, GPIO_DATA, data);
-       msleep(50);
+       hw_adc_start(hw);
 
        /* I2C write to register offset 0x0B to set ADC LRCLK polarity */
        /* invert bit, interface format to I2S, word length to 24-bit, */