imx8mp-hdmi-pai.c

  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright 2025 NXP
  4 */
  5
  6#include <linux/bitfield.h>
  7#include <linux/component.h>
  8#include <linux/module.h>
  9#include <linux/of_platform.h>
 10#include <linux/platform_device.h>
 11#include <linux/pm_runtime.h>
 12#include <linux/regmap.h>
 13#include <drm/bridge/dw_hdmi.h>
 14#include <sound/asoundef.h>
 15
 16#define HTX_PAI_CTRL			0x00
 17#define   ENABLE			BIT(0)
 18
 19#define HTX_PAI_CTRL_EXT		0x04
 20#define   WTMK_HIGH_MASK		GENMASK(31, 24)
 21#define   WTMK_LOW_MASK			GENMASK(23, 16)
 22#define   NUM_CH_MASK			GENMASK(10, 8)
 23#define   WTMK_HIGH(n)			FIELD_PREP(WTMK_HIGH_MASK, (n))
 24#define   WTMK_LOW(n)			FIELD_PREP(WTMK_LOW_MASK, (n))
 25#define   NUM_CH(n)			FIELD_PREP(NUM_CH_MASK, (n) - 1)
 26
 27#define HTX_PAI_FIELD_CTRL		0x08
 28#define   PRE_SEL			GENMASK(28, 24)
 29#define   D_SEL				GENMASK(23, 20)
 30#define   V_SEL				GENMASK(19, 15)
 31#define   U_SEL				GENMASK(14, 10)
 32#define   C_SEL				GENMASK(9, 5)
 33#define   P_SEL				GENMASK(4, 0)
 34
 35struct imx8mp_hdmi_pai {
 36	struct regmap	*regmap;
 37	struct device	*dev;
 38};
 39
 40static void imx8mp_hdmi_pai_enable(struct dw_hdmi *dw_hdmi, int channel,
 41				   int width, int rate, int non_pcm,
 42				   int iec958)
 43{
 44	const struct dw_hdmi_plat_data *pdata = dw_hdmi_to_plat_data(dw_hdmi);
 45	struct imx8mp_hdmi_pai *hdmi_pai = pdata->priv_audio;
 46	int val;
 47
 48	if (pm_runtime_resume_and_get(hdmi_pai->dev) < 0)
 49		return;
 50
 51	/* PAI set control extended */
 52	val =  WTMK_HIGH(3) | WTMK_LOW(3);
 53	val |= NUM_CH(channel);
 54	regmap_write(hdmi_pai->regmap, HTX_PAI_CTRL_EXT, val);
 55
 56	/* IEC60958 format */
 57	if (iec958) {
 58		val = FIELD_PREP_CONST(P_SEL,
 59				       __bf_shf(IEC958_SUBFRAME_PARITY));
 60		val |= FIELD_PREP_CONST(C_SEL,
 61					__bf_shf(IEC958_SUBFRAME_CHANNEL_STATUS));
 62		val |= FIELD_PREP_CONST(U_SEL,
 63					__bf_shf(IEC958_SUBFRAME_USER_DATA));
 64		val |= FIELD_PREP_CONST(V_SEL,
 65					__bf_shf(IEC958_SUBFRAME_VALIDITY));
 66		val |= FIELD_PREP_CONST(D_SEL,
 67					__bf_shf(IEC958_SUBFRAME_SAMPLE_24_MASK));
 68		val |= FIELD_PREP_CONST(PRE_SEL,
 69					__bf_shf(IEC958_SUBFRAME_PREAMBLE_MASK));
 70	} else {
 71		/*
 72		 * The allowed PCM widths are 24bit and 32bit, as they are supported
 73		 * by aud2htx module.
 74		 * for 24bit, D_SEL = 0, select all the bits.
 75		 * for 32bit, D_SEL = 8, select 24bit in MSB.
 76		 */
 77		val = FIELD_PREP(D_SEL, width - 24);
 78	}
 79
 80	regmap_write(hdmi_pai->regmap, HTX_PAI_FIELD_CTRL, val);
 81
 82	/* PAI start running */
 83	regmap_write(hdmi_pai->regmap, HTX_PAI_CTRL, ENABLE);
 84}
 85
 86static void imx8mp_hdmi_pai_disable(struct dw_hdmi *dw_hdmi)
 87{
 88	const struct dw_hdmi_plat_data *pdata = dw_hdmi_to_plat_data(dw_hdmi);
 89	struct imx8mp_hdmi_pai *hdmi_pai = pdata->priv_audio;
 90
 91	/* Stop PAI */
 92	regmap_write(hdmi_pai->regmap, HTX_PAI_CTRL, 0);
 93
 94	pm_runtime_put_sync(hdmi_pai->dev);
 95}
 96
 97static const struct regmap_config imx8mp_hdmi_pai_regmap_config = {
 98	.reg_bits = 32,
 99	.reg_stride = 4,
100	.val_bits = 32,
101	.max_register = HTX_PAI_FIELD_CTRL,
102};
103
104static int imx8mp_hdmi_pai_bind(struct device *dev, struct device *master, void *data)
105{
106	struct platform_device *pdev = to_platform_device(dev);
107	struct dw_hdmi_plat_data *plat_data = data;
108	struct imx8mp_hdmi_pai *hdmi_pai;
109	struct resource *res;
110	void __iomem *base;
111	int ret;
112
113	hdmi_pai = devm_kzalloc(dev, sizeof(*hdmi_pai), GFP_KERNEL);
114	if (!hdmi_pai)
115		return -ENOMEM;
116
117	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
118	if (IS_ERR(base))
119		return PTR_ERR(base);
120
121	hdmi_pai->regmap = devm_regmap_init_mmio_clk(dev, "apb", base,
122						     &imx8mp_hdmi_pai_regmap_config);
123	if (IS_ERR(hdmi_pai->regmap)) {
124		dev_err(dev, "regmap init failed\n");
125		return PTR_ERR(hdmi_pai->regmap);
126	}
127
128	plat_data->enable_audio = imx8mp_hdmi_pai_enable;
129	plat_data->disable_audio = imx8mp_hdmi_pai_disable;
130	plat_data->priv_audio = hdmi_pai;
131
132	hdmi_pai->dev = dev;
133	ret = devm_pm_runtime_enable(dev);
134	if (ret < 0) {
135		dev_err(dev, "failed to enable PM runtime: %d\n", ret);
136		return ret;
137	}
138
139	return 0;
140}
141
142static const struct component_ops imx8mp_hdmi_pai_ops = {
143	.bind   = imx8mp_hdmi_pai_bind,
144};
145
146static int imx8mp_hdmi_pai_probe(struct platform_device *pdev)
147{
148	return component_add(&pdev->dev, &imx8mp_hdmi_pai_ops);
149}
150
151static void imx8mp_hdmi_pai_remove(struct platform_device *pdev)
152{
153	component_del(&pdev->dev, &imx8mp_hdmi_pai_ops);
154}
155
156static const struct of_device_id imx8mp_hdmi_pai_of_table[] = {
157	{ .compatible = "fsl,imx8mp-hdmi-pai" },
158	{ /* Sentinel */ }
159};
160MODULE_DEVICE_TABLE(of, imx8mp_hdmi_pai_of_table);
161
162static struct platform_driver imx8mp_hdmi_pai_platform_driver = {
163	.probe		= imx8mp_hdmi_pai_probe,
164	.remove		= imx8mp_hdmi_pai_remove,
165	.driver		= {
166		.name	= "imx8mp-hdmi-pai",
167		.of_match_table = imx8mp_hdmi_pai_of_table,
168	},
169};
170module_platform_driver(imx8mp_hdmi_pai_platform_driver);
171
172MODULE_DESCRIPTION("i.MX8MP HDMI PAI driver");
173MODULE_LICENSE("GPL");