ASoC: cs35l56: Create debugfs files for factory calibration

Create debugfs files that can be used to perform factory calibration.

During manufacture, the production line must perform a factory calibration
of the amps. This patch adds this functionality via debugfs files.

As this is only needed during manufacture, there is no need for this to be
available in a normal system so a Kconfig item has been added to enable
this. The new Kconfig option is inside a sub-menu because items do not
group and indent if the parent is invisible or there are multiple parent
dependencies. Anyway the sub-menu reduces the clutter.

Signed-off-by: Richard Fitzgerald <[e-mail]>
Reviewed-by: Takashi Iwai <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/codecs/Kconfig

···
 config SND_SOC_CS35L56_CAL_DEBUGFS_COMMON
 	bool
 
+menu "CS35L56 driver options"
+	depends on SND_SOC_CS35L56
+
+config SND_SOC_CS35L56_CAL_DEBUGFS
+	bool "CS35L56 create debugfs for factory calibration"
+	default N
+	depends on DEBUG_FS
+	select SND_SOC_CS35L56_CAL_DEBUGFS_COMMON
+	help
+	  Create debugfs entries used during factory-line manufacture
+	  for factory calibration.
+
+	  If unsure select "N".
+endmenu
+
 config SND_SOC_CS40L50
 	tristate "Cirrus Logic CS40L50 CODEC"
 	depends on MFD_CS40L50_CORE

sound/soc/codecs/cs35l56.c

···
 #include <linux/completion.h>
 #include <linux/debugfs.h>
 #include <linux/delay.h>
+#include <linux/device.h>
 #include <linux/err.h>
 #include <linux/gpio/consumer.h>
 #include <linux/interrupt.h>
···
 	SND_SOC_DAPM_SIGGEN("VDDBMON ADC"),
 	SND_SOC_DAPM_SIGGEN("VBSTMON ADC"),
 	SND_SOC_DAPM_SIGGEN("TEMPMON ADC"),
+
+	SND_SOC_DAPM_INPUT("Calibrate"),
 };
 
 #define CS35L56_SRC_ROUTE(name) \
···
 	{ "DSP1", NULL, "ASP1RX1" },
 	{ "DSP1", NULL, "ASP1RX2" },
 	{ "DSP1", NULL, "SDW1 Playback" },
+	{ "DSP1", NULL, "Calibrate" },
 	{ "AMP", NULL, "DSP1" },
 	{ "SPK", NULL, "AMP" },
 
···
 	pm_runtime_put_autosuspend(cs35l56->base.dev);
 }
 
+static struct snd_soc_dapm_context *cs35l56_power_up_for_cal(struct cs35l56_private *cs35l56)
+{
+	struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(cs35l56->component);
+	int ret;
+
+	ret = snd_soc_component_enable_pin(cs35l56->component, "Calibrate");
+	if (ret)
+		return ERR_PTR(ret);
+
+	snd_soc_dapm_sync(dapm);
+
+	return dapm;
+}
+
+static void cs35l56_power_down_after_cal(struct cs35l56_private *cs35l56)
+{
+	struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(cs35l56->component);
+
+	snd_soc_component_disable_pin(cs35l56->component, "Calibrate");
+	snd_soc_dapm_sync(dapm);
+}
+
+static ssize_t cs35l56_debugfs_calibrate_write(struct file *file,
+					       const char __user *from,
+					       size_t count, loff_t *ppos)
+{
+	struct cs35l56_base *cs35l56_base = file->private_data;
+	struct cs35l56_private *cs35l56 = cs35l56_private_from_base(cs35l56_base);
+	struct snd_soc_dapm_context *dapm;
+	ssize_t ret;
+
+	dapm = cs35l56_power_up_for_cal(cs35l56);
+	if (IS_ERR(dapm))
+		return PTR_ERR(dapm);
+
+	snd_soc_dapm_mutex_lock(dapm);
+	ret = cs35l56_calibrate_debugfs_write(&cs35l56->base, from, count, ppos);
+	snd_soc_dapm_mutex_unlock(dapm);
+
+	cs35l56_power_down_after_cal(cs35l56);
+
+	return ret;
+}
+
+static ssize_t cs35l56_debugfs_cal_temperature_write(struct file *file,
+						     const char __user *from,
+						     size_t count, loff_t *ppos)
+{
+	struct cs35l56_base *cs35l56_base = file->private_data;
+	struct cs35l56_private *cs35l56 = cs35l56_private_from_base(cs35l56_base);
+	struct snd_soc_dapm_context *dapm;
+	ssize_t ret;
+
+	dapm = cs35l56_power_up_for_cal(cs35l56);
+	if (IS_ERR(dapm))
+		return PTR_ERR(dapm);
+
+	ret = cs35l56_cal_ambient_debugfs_write(&cs35l56->base, from, count, ppos);
+	cs35l56_power_down_after_cal(cs35l56);
+
+	return ret;
+}
+
+static ssize_t cs35l56_debugfs_cal_data_read(struct file *file,
+					     char __user *to,
+					     size_t count, loff_t *ppos)
+{
+	struct cs35l56_base *cs35l56_base = file->private_data;
+	struct cs35l56_private *cs35l56 = cs35l56_private_from_base(cs35l56_base);
+	struct snd_soc_dapm_context *dapm;
+	ssize_t ret;
+
+	dapm = cs35l56_power_up_for_cal(cs35l56);
+	if (IS_ERR(dapm))
+		return PTR_ERR(dapm);
+
+	ret = cs35l56_cal_data_debugfs_read(&cs35l56->base, to, count, ppos);
+	cs35l56_power_down_after_cal(cs35l56);
+
+	return ret;
+}
+
+static int cs35l56_new_cal_data_apply(struct cs35l56_private *cs35l56)
+{
+	struct snd_soc_dapm_context *dapm;
+	int ret;
+
+	if (!cs35l56->base.cal_data_valid)
+		return -ENXIO;
+
+	if (cs35l56->base.secured)
+		return -EACCES;
+
+	dapm = cs35l56_power_up_for_cal(cs35l56);
+	if (IS_ERR(dapm))
+		return PTR_ERR(dapm);
+
+	snd_soc_dapm_mutex_lock(dapm);
+	ret = cs_amp_write_cal_coeffs(&cs35l56->dsp.cs_dsp,
+				      cs35l56->base.calibration_controls,
+				      &cs35l56->base.cal_data);
+	if (ret == 0)
+		cs35l56_mbox_send(&cs35l56->base, CS35L56_MBOX_CMD_AUDIO_REINIT);
+	else
+		ret = -EIO;
+
+	snd_soc_dapm_mutex_unlock(dapm);
+	cs35l56_power_down_after_cal(cs35l56);
+
+	return ret;
+}
+
+static ssize_t cs35l56_debugfs_cal_data_write(struct file *file,
+					      const char __user *from,
+					      size_t count, loff_t *ppos)
+{
+	struct cs35l56_base *cs35l56_base = file->private_data;
+	struct cs35l56_private *cs35l56 = cs35l56_private_from_base(cs35l56_base);
+	int ret;
+
+	ret = cs35l56_cal_data_debugfs_write(&cs35l56->base, from, count, ppos);
+	if (ret == -ENODATA)
+		return count;	/* Ignore writes of empty cal blobs */
+	else if (ret < 0)
+		return -EIO;
+
+	ret = cs35l56_new_cal_data_apply(cs35l56);
+	if (ret)
+		return ret;
+
+	return count;
+}
+
+static const struct cs35l56_cal_debugfs_fops cs35l56_cal_debugfs_fops = {
+	.calibrate = {
+		.write = cs35l56_debugfs_calibrate_write,
+	},
+	.cal_temperature = {
+		.write = cs35l56_debugfs_cal_temperature_write,
+	},
+	.cal_data = {
+		.read = cs35l56_debugfs_cal_data_read,
+		.write = cs35l56_debugfs_cal_data_write,
+	},
+};
+
 static int cs35l56_set_fw_suffix(struct cs35l56_private *cs35l56)
 {
 	if (cs35l56->dsp.fwf_suffix)
···
 	if (ret)
 		return dev_err_probe(cs35l56->base.dev, ret, "unable to add controls\n");
 
+	ret = snd_soc_component_disable_pin(component, "Calibrate");
+	if (ret)
+		return ret;
+
+	if (IS_ENABLED(CONFIG_SND_SOC_CS35L56_CAL_DEBUGFS))
+		cs35l56_create_cal_debugfs(&cs35l56->base, &cs35l56_cal_debugfs_fops);
+
 	queue_work(cs35l56->dsp_wq, &cs35l56->dsp_work);
 
 	return 0;
···
 	struct cs35l56_private *cs35l56 = snd_soc_component_get_drvdata(component);
 
 	cancel_work_sync(&cs35l56->dsp_work);
+
+	cs35l56_remove_cal_debugfs(&cs35l56->base);
 
 	if (cs35l56->dsp.cs_dsp.booted)
 		wm_adsp_power_down(&cs35l56->dsp);

sound/soc/codecs/cs35l56.h

···
 #define CS35L56_H
 
 #include <linux/completion.h>
+#include <linux/container_of.h>
 #include <linux/regulator/consumer.h>
 #include <linux/pm_runtime.h>
 #include <linux/workqueue.h>
···
 	u8 sdw_link_num;
 	u8 sdw_unique_id;
 };
+
+static inline struct cs35l56_private *cs35l56_private_from_base(struct cs35l56_base *cs35l56_base)
+{
+	return container_of(cs35l56_base, struct cs35l56_private, base);
+}
 
 extern const struct dev_pm_ops cs35l56_pm_ops_i2c_spi;