pwm: meson: Add generic compatible for meson8 to sm1

Introduce a new compatible support in the Amlogic PWM driver.

The PWM HW is actually the same for all SoCs supported so far. A specific
compatible is needed only because the clock sources of the PWMs are
hard-coded in the driver.

It is better to have the clock source described in DT but this changes the
bindings so a new compatible must be introduced.

When all supported platform have migrated to the new compatible, support
for the legacy ones may be removed from the driver.

The addition of this new compatible makes the old ones obsolete, as
described in the DT documentation.

Adding a callback to setup the clock will also make it easier to add
support for the new PWM HW found in a1, s4, c3 and t7 SoC families.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20240221151154.26452-6-jbrunet@baylibre.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Author: jbrun3t

drivers/pwm/pwm-meson.c

@@ -98,6 +98,7 @@ struct meson_pwm_channel {
 
 struct meson_pwm_data {
 	const char *const parent_names[MESON_NUM_MUX_PARENTS];
+	int (*channels_init)(struct pwm_chip *chip);
 };
 
 struct meson_pwm {
@@ -338,86 +339,16 @@ static const struct pwm_ops meson_pwm_ops = {
 	.get_state = meson_pwm_get_state,
 };
 
-static const struct meson_pwm_data pwm_meson8b_data = {
-	.parent_names = { "xtal", NULL, "fclk_div4", "fclk_div3" },
-};
-
-/*
- * Only the 2 first inputs of the GXBB AO PWMs are valid
- * The last 2 are grounded
- */
-static const struct meson_pwm_data pwm_gxbb_ao_data = {
-	.parent_names = { "xtal", "clk81", NULL, NULL },
-};
-
-static const struct meson_pwm_data pwm_axg_ee_data = {
-	.parent_names = { "xtal", "fclk_div5", "fclk_div4", "fclk_div3" },
-};
-
-static const struct meson_pwm_data pwm_axg_ao_data = {
-	.parent_names = { "xtal", "axg_ao_clk81", "fclk_div4", "fclk_div5" },
-};
-
-static const struct meson_pwm_data pwm_g12a_ao_ab_data = {
-	.parent_names = { "xtal", "g12a_ao_clk81", "fclk_div4", "fclk_div5" },
-};
-
-static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
-	.parent_names = { "xtal", "g12a_ao_clk81", NULL, NULL },
-};
-
-static const struct of_device_id meson_pwm_matches[] = {
-	{
-		.compatible = "amlogic,meson8b-pwm",
-		.data = &pwm_meson8b_data
-	},
-	{
-		.compatible = "amlogic,meson-gxbb-pwm",
-		.data = &pwm_meson8b_data
-	},
-	{
-		.compatible = "amlogic,meson-gxbb-ao-pwm",
-		.data = &pwm_gxbb_ao_data
-	},
-	{
-		.compatible = "amlogic,meson-axg-ee-pwm",
-		.data = &pwm_axg_ee_data
-	},
-	{
-		.compatible = "amlogic,meson-axg-ao-pwm",
-		.data = &pwm_axg_ao_data
-	},
-	{
-		.compatible = "amlogic,meson-g12a-ee-pwm",
-		.data = &pwm_meson8b_data
-	},
-	{
-		.compatible = "amlogic,meson-g12a-ao-pwm-ab",
-		.data = &pwm_g12a_ao_ab_data
-	},
-	{
-		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
-		.data = &pwm_g12a_ao_cd_data
-	},
-	{},
-};
-MODULE_DEVICE_TABLE(of, meson_pwm_matches);
-
-static int meson_pwm_init_channels(struct pwm_chip *chip)
+static int meson_pwm_init_clocks_meson8b(struct pwm_chip *chip,
+					 struct clk_parent_data *mux_parent_data)
 {
 	struct meson_pwm *meson = to_meson_pwm(chip);
-	struct clk_parent_data mux_parent_data[MESON_NUM_MUX_PARENTS] = {};
 	struct device *dev = pwmchip_parent(chip);
 	unsigned int i;
 	char name[255];
 	int err;
 
-	for (i = 0; i < MESON_NUM_MUX_PARENTS; i++) {
-		mux_parent_data[i].index = -1;
-		mux_parent_data[i].name = meson->data->parent_names[i];
-	}
-
-	for (i = 0; i < chip->npwm; i++) {
+	for (i = 0; i < MESON_NUM_PWMS; i++) {
 		struct meson_pwm_channel *channel = &meson->channels[i];
 		struct clk_parent_data div_parent = {}, gate_parent = {};
 		struct clk_init_data init = {};
@@ -495,6 +426,122 @@ static int meson_pwm_init_channels(struct pwm_chip *chip)
 	return 0;
 }
 
+static int meson_pwm_init_channels_meson8b_legacy(struct pwm_chip *chip)
+{
+	struct clk_parent_data mux_parent_data[MESON_NUM_MUX_PARENTS] = {};
+	struct meson_pwm *meson = to_meson_pwm(chip);
+	int i;
+
+	dev_warn_once(pwmchip_parent(chip),
+		      "using obsolete compatible, please consider updating dt\n");
+
+	for (i = 0; i < MESON_NUM_MUX_PARENTS; i++) {
+		mux_parent_data[i].index = -1;
+		mux_parent_data[i].name = meson->data->parent_names[i];
+	}
+
+	return meson_pwm_init_clocks_meson8b(chip, mux_parent_data);
+}
+
+static int meson_pwm_init_channels_meson8b_v2(struct pwm_chip *chip)
+{
+	struct clk_parent_data mux_parent_data[MESON_NUM_MUX_PARENTS] = {};
+	int i;
+
+	/*
+	 * NOTE: Instead of relying on the hard coded names in the driver
+	 * as the legacy version, this relies on DT to provide the list of
+	 * clocks.
+	 * For once, using input numbers actually makes more sense than names.
+	 * Also DT requires clock-names to be explicitly ordered, so there is
+	 * no point bothering with clock names in this case.
+	 */
+	for (i = 0; i < MESON_NUM_MUX_PARENTS; i++)
+		mux_parent_data[i].index = i;
+
+	return meson_pwm_init_clocks_meson8b(chip, mux_parent_data);
+}
+
+static const struct meson_pwm_data pwm_meson8b_data = {
+	.parent_names = { "xtal", NULL, "fclk_div4", "fclk_div3" },
+	.channels_init = meson_pwm_init_channels_meson8b_legacy,
+};
+
+/*
+ * Only the 2 first inputs of the GXBB AO PWMs are valid
+ * The last 2 are grounded
+ */
+static const struct meson_pwm_data pwm_gxbb_ao_data = {
+	.parent_names = { "xtal", "clk81", NULL, NULL },
+	.channels_init = meson_pwm_init_channels_meson8b_legacy,
+};
+
+static const struct meson_pwm_data pwm_axg_ee_data = {
+	.parent_names = { "xtal", "fclk_div5", "fclk_div4", "fclk_div3" },
+	.channels_init = meson_pwm_init_channels_meson8b_legacy,
+};
+
+static const struct meson_pwm_data pwm_axg_ao_data = {
+	.parent_names = { "xtal", "axg_ao_clk81", "fclk_div4", "fclk_div5" },
+	.channels_init = meson_pwm_init_channels_meson8b_legacy,
+};
+
+static const struct meson_pwm_data pwm_g12a_ao_ab_data = {
+	.parent_names = { "xtal", "g12a_ao_clk81", "fclk_div4", "fclk_div5" },
+	.channels_init = meson_pwm_init_channels_meson8b_legacy,
+};
+
+static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
+	.parent_names = { "xtal", "g12a_ao_clk81", NULL, NULL },
+	.channels_init = meson_pwm_init_channels_meson8b_legacy,
+};
+
+static const struct meson_pwm_data pwm_meson8_v2_data = {
+	.channels_init = meson_pwm_init_channels_meson8b_v2,
+};
+
+static const struct of_device_id meson_pwm_matches[] = {
+	{
+		.compatible = "amlogic,meson8-pwm-v2",
+		.data = &pwm_meson8_v2_data
+	},
+	/* The following compatibles are obsolete */
+	{
+		.compatible = "amlogic,meson8b-pwm",
+		.data = &pwm_meson8b_data
+	},
+	{
+		.compatible = "amlogic,meson-gxbb-pwm",
+		.data = &pwm_meson8b_data
+	},
+	{
+		.compatible = "amlogic,meson-gxbb-ao-pwm",
+		.data = &pwm_gxbb_ao_data
+	},
+	{
+		.compatible = "amlogic,meson-axg-ee-pwm",
+		.data = &pwm_axg_ee_data
+	},
+	{
+		.compatible = "amlogic,meson-axg-ao-pwm",
+		.data = &pwm_axg_ao_data
+	},
+	{
+		.compatible = "amlogic,meson-g12a-ee-pwm",
+		.data = &pwm_meson8b_data
+	},
+	{
+		.compatible = "amlogic,meson-g12a-ao-pwm-ab",
+		.data = &pwm_g12a_ao_ab_data
+	},
+	{
+		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
+		.data = &pwm_g12a_ao_cd_data
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, meson_pwm_matches);
+
 static int meson_pwm_probe(struct platform_device *pdev)
 {
 	struct pwm_chip *chip;
@@ -515,7 +562,7 @@ static int meson_pwm_probe(struct platform_device *pdev)
 
 	meson->data = of_device_get_match_data(&pdev->dev);
 
-	err = meson_pwm_init_channels(chip);
+	err = meson->data->channels_init(chip);
 	if (err < 0)
 		return err;