ASoC: codecs: wsa883x: Handle shared reset GPIO for WSA883x speakers

On some Qualcomm platforms such as QCS6490-RB3Gen2, the multiple
WSA8830/WSA8835 speaker amplifiers share a common reset (shutdown) GPIO.

To handle such scenario, use the reset controller framework and its
"reset-gpio" driver to handle such case. This allows proper handling
of all WSA883x speaker amplifiers on QCS6490-RB3Gen2 board.

Signed-off-by: Mohammad Rafi Shaik <quic_mohs@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
Link: https://patch.msgid.link/20250815172353.2430981-3-mohammad.rafi.shaik@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/wsa883x.c b/sound/soc/codecs/wsa883x.c
index 188363b03b9371f0850c3d375c8ded5138df9cbe..ca4520ade79aa2c9377449e29cdd33e9e8dd28c5 100644 (file)
--- a/sound/soc/codecs/wsa883x.c
+++ b/sound/soc/codecs/wsa883x.c
@@ -14,6 +14,7 @@
 #include <linux/printk.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 #include <linux/soundwire/sdw.h>
 #include <linux/soundwire/sdw_registers.h>
@@ -468,6 +469,7 @@ struct wsa883x_priv {
        struct sdw_stream_runtime *sruntime;
        struct sdw_port_config port_config[WSA883X_MAX_SWR_PORTS];
        struct gpio_desc *sd_n;
+       struct reset_control *sd_reset;
        bool port_prepared[WSA883X_MAX_SWR_PORTS];
        bool port_enable[WSA883X_MAX_SWR_PORTS];
        int active_ports;
@@ -1546,6 +1548,46 @@ static const struct hwmon_chip_info wsa883x_hwmon_chip_info = {
        .info   = wsa883x_hwmon_info,
 };
 
+static void wsa883x_reset_assert(void *data)
+{
+       struct wsa883x_priv *wsa883x = data;
+
+       if (wsa883x->sd_reset)
+               reset_control_assert(wsa883x->sd_reset);
+       else
+               gpiod_direction_output(wsa883x->sd_n, 1);
+}
+
+static void wsa883x_reset_deassert(struct wsa883x_priv *wsa883x)
+{
+       if (wsa883x->sd_reset)
+               reset_control_deassert(wsa883x->sd_reset);
+       else
+               gpiod_direction_output(wsa883x->sd_n, 0);
+}
+
+static int wsa883x_get_reset(struct device *dev, struct wsa883x_priv *wsa883x)
+{
+       wsa883x->sd_reset = devm_reset_control_get_optional_shared(dev, NULL);
+       if (IS_ERR(wsa883x->sd_reset))
+               return dev_err_probe(dev, PTR_ERR(wsa883x->sd_reset),
+                                    "Failed to get reset\n");
+       /*
+        * if sd_reset: NULL, so use the backwards compatible way for powerdown-gpios,
+        * which does not handle sharing GPIO properly.
+        */
+       if (!wsa883x->sd_reset) {
+               wsa883x->sd_n = devm_gpiod_get_optional(dev, "powerdown",
+                                                       GPIOD_FLAGS_BIT_NONEXCLUSIVE |
+                                                       GPIOD_OUT_HIGH);
+               if (IS_ERR(wsa883x->sd_n))
+                       return dev_err_probe(dev, PTR_ERR(wsa883x->sd_n),
+                                            "Shutdown Control GPIO not found\n");
+       }
+
+       return 0;
+}
+
 static int wsa883x_probe(struct sdw_slave *pdev,
                         const struct sdw_device_id *id)
 {
@@ -1566,13 +1608,9 @@ static int wsa883x_probe(struct sdw_slave *pdev,
        if (ret)
                return dev_err_probe(dev, ret, "Failed to enable vdd regulator\n");
 
-       wsa883x->sd_n = devm_gpiod_get_optional(dev, "powerdown",
-                                               GPIOD_FLAGS_BIT_NONEXCLUSIVE | GPIOD_OUT_HIGH);
-       if (IS_ERR(wsa883x->sd_n)) {
-               ret = dev_err_probe(dev, PTR_ERR(wsa883x->sd_n),
-                                   "Shutdown Control GPIO not found\n");
+       ret = wsa883x_get_reset(dev, wsa883x);
+       if (ret)
                goto err;
-       }
 
        dev_set_drvdata(dev, wsa883x);
        wsa883x->slave = pdev;
@@ -1595,11 +1633,14 @@ static int wsa883x_probe(struct sdw_slave *pdev,
        pdev->prop.simple_clk_stop_capable = true;
        pdev->prop.sink_dpn_prop = wsa_sink_dpn_prop;
        pdev->prop.scp_int1_mask = SDW_SCP_INT1_BUS_CLASH | SDW_SCP_INT1_PARITY;
-       gpiod_direction_output(wsa883x->sd_n, 0);
+
+       wsa883x_reset_deassert(wsa883x);
+       ret = devm_add_action_or_reset(dev, wsa883x_reset_assert, wsa883x);
+       if (ret)
+               return ret;
 
        wsa883x->regmap = devm_regmap_init_sdw(pdev, &wsa883x_regmap_config);
        if (IS_ERR(wsa883x->regmap)) {
-               gpiod_direction_output(wsa883x->sd_n, 1);
                ret = dev_err_probe(dev, PTR_ERR(wsa883x->regmap),
                                    "regmap_init failed\n");
                goto err;